IMPROVED PROCESSES BASED ON RADICAL POLYMERIZATIONOF TRANSFER OF ATOM (OR GROUP) AND NOVEDOSOS (CO) POLYMERS THAT HAVE USEFUL PROPERTIES AND STRUCTURESBACKGROUND OF THE INVENTION Field of the Invention The present invention concerns novel (co) polymers and a novel radical polymerization process based on transition metal transition group or atom polymerization ("atom transfer radical polymerization") .
Discussion of the background The living polymerization yields unique possibilities of preparing a multitude of polymers, which are well defined in terms of molecular dimension, polydispersity, topology, composition, functionalization and microstructure. Many living systems based on anionic, cationic initiators and various other types of initiators have been developed over the past 40 years (see O.W. Webster, Science, 251, 887 (1991)). However, in comparison with other living systems, the polymerization of living radical represented a poorly resolved challenge before the present invention. It was difficult to control the molecular weight and polydispersity to achieve a highly uniform product of desired structure by previous radical polymerization processes.
On the other hand, radical polymerization offers the advantages of being applicable to the polymerization of a wide variety of commercially important monomers, many of which can not be polymerized by other polymerization processes. Moreover, it is easier to make random copolymers by radical polymerization than by other polymerization processes (eg, ionic). Certain block copolymers can not be made by other polymerization processes. In addition, the radical polymerization processes can be conducted in bulk, in solution, in suspension or in an emulsion, in contrast to other polymerization processes. In this way, it is a strongly felt need for a radical polymerization process which provides (co) polymers having a predetermined molecular weight, a narrow molecular weight distribution (low "polydispersity"), various topologies and uniform, controlled structures. Three approaches for the preparation of controlled polymers in a "living" radical process have been described (Greszta et al Macromolecules, 27, 638 (1994)). The first approach involves the situation where growing radicals react reversibly with expelling radicals to form covalent species. The second approach involves the situation where growing radicals react reversibly with covalent species to produce persistent radicals. The third approach involves the situation where growing radicals participate in a degenerative transfer reaction, which regenerates the same type of radicals.
There are some patents and articles on living / controlled radical polymerization. Some of the better controlled polymers obtained by "living" radical polymerization are prepared with preformed alkoxyamines or those prepared in situ (U.S. Patent 4,581, 429; Hawker J. Am. Chem. Soc, 16, 1185 (1994)).; Georges et al., WO 94/1 1412; Georges et al, Macromolecules, 26, 2987 (1993)). A complex containing Co has been used to prepare "living" polyacrylates (Wayland, B.B., Pszmik, G., Mukerjee, S.L., Fryd, M.J. Am. Chem. Soc, 116, 7943 (1994)). A "living" poly (vinyl acetate) can be prepared using an Al (i-Bu) 3: Bpy: TEMPO initiator system (Mardare et al Macromolecules, 27, 645 (1994)). An initiator system based on benzoyl peroxide and chromium acetate has been used to drive the controlled radical polymerization of methyl methacrylate and vinyl acetate (Lee et al., J. Chem. Soc. Trans. Faraday Soc. I, 74, 1726 (1978); Mardare et al., Polym. Prep. (ACS), 36 (1) (1995)). However, none of these "living" polymerization systems include an atom transfer process based on a redox reaction with a transition metal compound. A document describes an "iniferter" redox system based on benzyl halides and Ni (O). However, a very broad bimodal molecular weight distribution was obtained, and the efficiency of the initiator based on benzyl halides used was approximately 1-2% or less (T. Otsu, T. Tashinori, M. Yoshioka, Chem. Express 1990, 5 (10), 801). Tasaki et al (Mem. Fac. Eng., Osaka City Univ., Vol 30 (1989), pages 103-1 13) describe an "iniferter" redox system based on reduced nickel and benzyl halides or xylylene dihalides. The above examples described by Tasaki et al do not include a coordination ligand. Tazaki et al also describe the polymerization of styrene and methyl methacrylate using its "iniferter" system. These systems are similar to the redox primers developed before (Banrford, in Comprehensive Polymer Science, Alien, G., Aggarwal, SL, Russo, S., eds., Pergamon: Oxford, 1991, vol.3, P. 123), in which the small amount of initiating radicals was generated by redox reaction between (1) RCHX2 or RCX3 (where X = Br, Cl) and (2) Ni (O) and other transition metals. The reversible deactivation of initiator radicals by oxidized Ni is very low compared to the propagation, resulting in very low initiator efficiency and a very broad and bimodal molecular weight distribution. Bamford (supra) also describes a Ni [P (OPh) 3] / CCI4 or CBr4 system for polymerizing methyl methacrylate or styrene, and the use of Mo (CO) n to prepare a graft copolymer of a polymer having a skeleton brominated and as a transition metal catalyst suitable for initiators of CCI, CBr4) or CCI3CO2Et to polymerize methyl methacrylate. Organic halides other than CCI and CBr4 are also described. It was shown as a source of CCI3 radicals. Bamford also showed that systems such as Mn (acac) 3 and some vanadium (V) systems have been used as a source of radicals, rather than as a catalyst to transfer radicals. A number of the systems described by Bamford are "self-inhibitors" (ie, an initiation intermediary interferes with the generation of the radical). Other systems require monomer coordination and / or photoinitiation to proceed. It is also suggested that photoinitiator systems result in the formation of metal-carbon bonds. In fact, it is also believed that Mn (CO) 5CI, a thermal initiator, forms Mn-C bonds under certain conditions. In each of the reactions described by Bamford. the speed of radical formation seems to be the speed limiting step. In this way, once a chain of growing radical is formed, the growth of the chain (propagation) apparently proceeds until the transfer or termination occurs. Another document describes the polymerization of methyl methacrylate, initiated by CC14 in the presence of RuCI2 (PPh3) 3- However, the reaction does not occur without added methylaluminum bis (2,6-di-tert-butylphenoxide) as an activator ( see M. Kato, M. Kamigaito, M. Sawamoto, T. Higashimura, Macromolecules, 28, 1721 (1995)). U.S. Patent No. 5,405,913 (for Harwood et al) describes a redox initiator system consisting of salts of Cu ", enolizable ketones and aldehydes (which do not contain any halogen atom), various combinations of coordination agents for Cu" and Cu1, and a base of strong amine that is not oxidized by Cu. "The Harwood et al process requires the use of a strong amine base to deprotonate the enolizable initiator (thus forming an enolate ion), which then transfers a single electron to Cu", consequently forming an enolyl radical and Cu1. The redox initiation process of Harwood et al is not reversible.
In each of the systems described by Tazaki et al. Otsu et al. Harwood et al and Bamford. Polymers were obtained having uncontrolled molecular weights and typical polydispersities for those produced by conventional radical processes (ie, > 1.5). Only the system described by Kato et al (Macromolecules, 28, 1721 (1995)) achieves lower polydispersities. However, the polymerization system of Kato et al requires an additional activator, reportedly being inactive when using CCI, transition metal and ligand alone. The addition of atom transfer radical, ATRA, is a known method for the formation of carbon-carbon ligation in organic synthesis. (For revisions of atom transfer methods in organic synthesis, see Curran, DP Synthesis, 1988, 489, Curran, DP in Free Radicals in Synthesis and Biology, Minisci, F., ed.KluwepDordrecht, 1989, p.37; Curran, DP in Comprehensive Organic Synthesis, Trost, BM, Fleming, I., eds., Pergamon: Oxford, 1991, Vol.4, page 715.) In a very broad class of ATRA, two types of transfer methods atoms have been long developed. One of them is known as atom abstraction or homolytic substitution (see Curran et al., J. Org. Chem., 1989, 54, 3140; and Curran et al., J. Am. Chem. Soc., 1994, 16, 4279), in which a univalent atom (typically a halogen) or a group (such as SPh or SePh) is transferred from a neutral molecule to a radical to form a new s-ligature and a new radical according to Scheme 1 to continuation:Scheme 1: Rj- + Rj-X. £ r =? Ri- + R¡ -X X = I, SePh, ...
In this regard, it was found that the iodine atom and the SePh group work very well, due to the presence of very weak Cl and C-SePh ligations together with the reactive radicals (Curran et al, J. Org. Chem. Am. Chem. Soc., Supra). In a previous work, the present inventors have discovered that alkyl iodides can induce the process of degenerative transfer in radical polymerization, leading to a controlled radical polymerization of several alkenes. This is consistent with the fact that the alkyl iodides are donors of protruding iodine atoms that can undergo a rapid and reversible transfer in a degenerative initiation and transfer step in a propagation step (see Gaynor et al., Polym, Prep. (Am. Chem. Soc, Polym, Chem. Div.), 1995, 36 (1), 467, Wang et al, Polym, Prep. (Am. Chem. Soc, Plym. Chem. Div.), 1995, 36 (1), 465; Matyjaszewski et al, Macromolecules, 1995, 28, 2093). In contrast, alkyl chlorides and bromides are relatively inefficient degenerative transfer reagents. Another method of atom transfer is promoted by a transition metal species (see Bellus, D. Pure & Appl. Chem. 1985, 57, 1827; Nagashima, H.; Ozaki, N.; Ishii, M.; Seki , K., Washiyama, M., Itoh, KJ Org. Chem. 1993, 58, 464; Udding, JH; Tuijp, KJ .M .; van Zanden, M. N. A.; Hiemstra, H.; Speckamp, W. N. J. Org. Chem. 1994, 59, 1993; Seiias et al., Tetrahedorn, 1992, 48 (9), 1637; Nagashima, H .; Wakamatsu, H .; Ozaki, N .; Ishii, T. Watanabe, M., Tajima, T., Itoh, KJ Org Chem. 1992, 57, 1682, Hayes, TK, Villani, R., Weinreb, SMJ Am. Chem. Soc. 1988, 1 10, 5533; et al., Syn. Lett., 1990, 217; and Hirao et al, J. Synth, Org. Chem. (Japan), 1994, 52 (3), 197; Iqbal, J; Bhatia, B .; Nayyar, NK Chem. Rev., 94, 519 (1994), Asscher, M., Vofsi, DJ Chem. Soc., 1963, 1887, and van de Kuil et al., Chem. Mater., 1994, 6, 1675). In these reactions, a catalytic amount of transition metal compound acts as a carrier of the halogen atom in a redox process. Initially, the transition metal species, Mtn, subtracts the halogen atom X from the organic halide, RX, to form the oxidized species, Mtn + 1X, and the radical centered on carbon R. "In the subsequent step, the radical, R ", reacts with alkene, M, with the formation of intermediate radical species, RM." The reaction between Mtn + 1X and RM 'results in the target product, RMX, and regenerates the species of reduced transition metal, Mtn , which reacts additionally with RX and promotes a new redox process The high efficiency of atom transfer reactions catalyzed by transition metal to produce the target product, RMX, in good to excellent yields (frequently >; 90%) may suggest that the presence of a redox process based on the Mtp / Mtn + 1 cycle can compete effectively with bimolecular termination reactions between radicals (see Curran, Synthesis, in Free Radicáis in Synthesis and Biology, and in Comprehensive Organic Synthesis, supra).
However, the simple presence of a transition metal compound does not ensure success in telomerization or polymerization, even in the presence of initiators capable of donating a radical group or atom. For example, Asscher et al (J. Chem. Soc, supra) reported that copper chloride completely abolishes telomerization. In addition, even where a transition metal compound is present and the telomerization or polymerization occurs, it is difficult to control the molecular weight and polydispersity (molecular weight distribution) of polymers produced by radical polymerization. In this way, it is often difficult to achieve a highly uniform and well-defined product. It is also often difficult to control the polymerization processes of the control radical with the degree of certainty required in specialized applications, such as in the preparation of final functional polymers, block copolymers, star (co) polymers, etc. In addition, although several initiator systems have been reported for "living" V controlled polymerization, no general route or process for "living" V controlled polymerization has been discovered. The copolymerization of electron donor type monomers (unsaturated hydrocarbons, vinyl ethers, etc.) with electron receptor-type monomers (acrylates, methacrylates, unsaturated nitriles, unsaturated ketones, etc.) in the presence of monomer complex agents ( ZnCl2, Et3Al2Cl3, etc.) produce highly, if not strictly alternating copolymers (Hiroka et al., J. Polym, Sci. Part B, 5, 47 (1967), Furukawa et al., Rubber Chem. Technol., 51 (3). , 601 (1979)). The copolymerization was successful, however, only if the polar monomer was significantly complexed by Lewis acid. Additionally, copolymerization was frequently initiated spontaneously, thereby yielding products of very high molecular weight having broad polydispersities. The mechanism of this reaction is controversial and there are suggestions that it is due to a complex (Hirai, J. Polym, Sci. Macromol, Rev., 11, 47 (1976)) or intensified cross-propagation velocities (Bamford et al. J. Polym, Sci. Polym, Lett. Ed., 19, 229 (1981) and J. Chem. Soc. Faraday Trans. 1, 78, 2497 (1982)). In the copolymerization of isobutylene radical (IB) and acrylic esters, the resulting copolymers contain at most 20-30% IB and have low molecular weights due to the degradative chain transfer of IB (US Patent Nos. 2,41 1 , 599 and 2,531, 196, and Mashita et al., Polymer, 36, 2973 (1995) Conjugated monomers such as acrylic esters and acrylonitrile react with donor monomers such as propylene, isobutylene, styrene in the presence of alkylaluminium halide to give 1: 1 alternating copolymers (Hirooka et al., J. Polym, Sci. Polym, Chem., 11, 1281 (1973)) The alternating copolymer was obtained when [Lewis acid] 0 / [acrylic esters] 0 = 0.9 and [IB] 0> [acrylic esters] 0. The copolymer of IB and methyl acrylate (MA) obtained by using ethylaluminum sesquichloride and 2-methyl pentanoyl peroxide as an initiator system is highly alternating, either with low isotacticity (Kuntz et al., J. Polym. i, Polym, Chem., 16, 1747 (1978)) or high (60%) in the presence of EtAICI2 (10 mol% relative to MA) at 50 ° C (Florjanczyk et al. Makromol Chem., 183, 1081 (1982)).
Recently, it was found that the alkylboro halide has a much higher activity than the alkylaluminum halide in the alternating copolymerization of IB and acrylic esters (Mashita et al, Polymer, 36, 2983 (1995)). The polymerization rate has a mum at about -50 ° C and decreased significantly above 0 ° C. The copolymerization is controlled by O2 in terms of both speed and molecular weight. The alternating copolymer was obtained when [IB] 0 > [acrylic esters] 0. Stereoregularity was considered to be closely random. The copolymer is an elastomer of high tensile strength and high temperature of thermal decomposition. The oil resistance is very good, especially at high temperatures, and the resistance to hydrolysis was excellent compared to that of the corresponding polyacrylic esters (Mashita et al., Supra).
Dendrimers have recently received much attention as materials with novel physical properties (DA Tomalia, AM Nyalor, WAG III, Angew, Chem., Int. Ed. Engl 29, 138 (1990), JMJ Frechet, Science 263, 1710 1994)). These polymers have lower viscosities than linear analogs of similar molecular weight, and the resulting macromolecules can be highly functionalized. However, the synthesis of dendrimers is not trivial and requires multiple steps, thus generally avoiding its commercial development. Polymers consisting of hyperbranched phenylenes (OW Webster, YH Kim, J. Am. Chem. Soc. 12, 4592 (1990) and Macromolecules 25, 5561 (1992)), aromatic esters (J.M. J. Frechet, CJ. Hawker, R. Lee, J. Am. Chem. Soc, 1 13, 4583 (1991)), aliphatic esters (A. Hult, E.
Malmstrom, M. Johansson, J. Polym. Sci. Poiym. Ed. 31, 619 (1993)), siloxanes (LJ Mathias, TW Carothers, J. Am. Chem. Soc. 113, 4043 (1991)), amines (M. Suzuki, A. Li, T. Saegusa, Macromolecules 25 , 7071 (1992)) and liquid crystals (V. Percec. M. Kawasumi, Macromelecules 25, 3843 (1992)) have been synthesized in recent years. Recently, a method has been described by which functionalized vinyl monomers could be used as monomers for the synthesis of hyperbranched polymers by cationic polymerization (J.M.J. Frechet, et al., Science 269, 1080 (1995)). The monomer satisfies the requirements of AB2 for the formation of hyperbranched polymers by the vinyl group acting as the difunctional group B, and an additional alkyl halide functional group as the group A. By activating the group A with a Lewis acid, Polymerization through double bonding can occur. In this method, 3- (1-chloroethyl) -ethenylbenzene was used as a monomer and was cationically polymerized in the presence of SnCl 4. A strong need is felt for a radical polymerization process, which provides (co) polymers having a predictable molecular weight and a controlled molecular weight distribution ("polydispersity"). An additional need is felt strongly for a radical polymerization process, which is sufficiently flexible to provide a wide variety of products, but which can be controlled to the degree necessary to provide highly uniform products with a controlled structure (ie, topology). controllable, composition, stereoregularity, etc.), many of which are suitable for highly specialized uses (such as thermoplastic elastomers, terminal functional polymers for extended chain polyurethanes, polyesters and polyamides, dispersants for polymer blends, etc.).
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a novel method for the radical polymerization of alkenes based on the polymerization of atom transfer radical (ATRP), which provides a level of molecular control over the polymerization process currently obtainable only by living exchange or ionic polymerization, and which leads to more uniform and more highly controllable products. A further objective of the present invention is to provide novel improvements to a method for radical polymerization of alkenes based on atom transfer radical polymerization(ATRP), that increases the efficiencies of the initiators and process yields, and improves the properties of the product. A further objective of the present invention is to provide a wide variety of novel (co) polymers having more uniform properties than those obtained by conventional radical polymerization. A further objective of the present invention is to provide novel (co) polymers having novel and useful structures and properties.
A further objective of the present invention is to provide a process for radically polymerizing a monomer, which is adaptable to be used with existing equipment. A further objective of the present invention is to provide a method for producing a (co) polymer, which depends on catalysts and readily available starting materials. A further objective of the present invention is to provide (co) polymers having a wide variety of compositions (eg, random, alternating, tapered, terminal functional, telechelic, etc.) and topologies (block, graft, star, dendritic or hyperbranched, comb, etc.) having uniform and / or well-defined properties and structures. A further objective of the present invention is to provide a novel method for radically polymerizing a monomer, which can use water as a solvent and which provides novel water-soluble (co) polymers. A further objective of the present invention is to provide novel (co) polymers, which are useful as gels and hydrogels, and to provide novel methods for making such (co) polymers. A further objective of the present invention is to provide novel (co) polymers, which are useful in a wide variety of applications (for example, as adhesives, asphalt modifiers, in contact lenses, as detergents, diagnostic agents and supports for the same, dispersants, emulsifiers, elastomers, engineering resins, viscosity index improvers, in image and ink compositions, as cement and skin modifiers, lubricants and / or surfactants, with paints and coatings, as paper additives and agents coating, as an intermediary to prepare larger macromolecules such as polyurethanes, as resin modifiers, in textiles, as water treatment chemicals, in chemical and chemical waste processing, compound manufacturing, cosmetics, hair products, products of personal care in plastic compositions such as, for example, an antistatic agent, in packaging food and beverages, pharmaceuticals [such as, for example, a bulking agent, sustained release or "slow release" composition agent], in rubber, and as a preservative). These and other objects of the present invention, which will be readily understood in the context of the following detailed description of the preferred embodiments, have been provided in part by a novel controlled process of atom radical transfer (or group) polymerization, comprising the steps of: polymerizing one or more polymerizable monomers by radical in the presence of an initiator system comprising: an initiator having an atom or group transferable by radical, a transition metal compound which participates in a reversible redox cycle (i.e., with the initiator), a sufficient amount of the redox conjugate of the transition metal compound to deactivate at least some initially formed radicals, and any N-, O-, P- or S- containing bound , which coordinates in a s-ligature or any ligand containing carbon which coordinates in a p-ligature to the transition metal n, or any carbon containing ligand which coordinates in a carbon-transition metal s-bond, but which does not form a carbon-carbon bond with said monomer under the polymerization conditions, to form a (co) polymer, and isolate the (co) polymer formed; and, in part, by novel (co) polymers prepared by atom (or group) radical transfer polymerization.
BRIEF DESCRIPTION OF THE FIGURES Figure 1 shows a variety of different polymer topologies, compositions and functionalizations, which can be achieved by the present invention, but to which the present invention is not restricted; Figure 2 shows a comparison of mechanisms, kinetic parameters and exemplary product properties of conventional radical polymerization with the present "living" controlled radical polymerization, Figures 3A-B are graphs of molecular weight (Mn) and polydispersities (Mw). / Mn) vs. time (Fig. 3A) and the instantaneous composition of the copolymer (F? Nst) vs. chain length (Fig. 3B) for the copolymerization gradient of Example 16 below;Figures 4A-B are graphs of molecular weight (Mn) and polydispersity (Mw / Mn) vs. time (Fig. 4A) and the instantaneous composition of the copolymer (Finst) vs. chain length (Fig. 4B) for the copolymerization gradient of Example 17 below; Figures 5A-B are graphs of molecular weight (Mn) and polydispersity (Mw / Mp) vs. time (Fig. 5A) and the instantaneous composition of the copolymer (F¡nst) vs. chain length (Fig. 5B) for the copolymerization gradient of Example 18 below; Figures 6A-B are graphs of molecular weight (Mn) and polydispersity (Mw / Mn) vs. time (Fig. 6A) and the instantaneous composition of the copolymer (Finst) vs. chain length (Fig. 6B) for the copolymerization gradient of Example 19 below; Figures 7A-B are graphs of molecular weight (Mn) and polydispersities (Mw / Mn) vs. time (Fig. 7A) and the instantaneous composition of the copolymer (F¡nst) vs. chain length (Fig. 7B) for the copolymerization gradient of Example 20 below; Figures 8A-B are graphs of molecular weight (Mn) and polydispersity (Mw / Mn) vs. time (Fig. 8A) and the instantaneous composition of the copolymer (F¡nst) vs. chain length (Fig. 8B) for the copolymerization gradient of Example 20 below; Figures 9A-B are graphs of molecular weight (Mn) and polydispersity (Mw / Mn) vs. time (Fig. 9A) and the instantaneous composition of the copolymer (F¡nst) vs. chain length (Fig. 9B) for the copolymerization gradient of Example 20 below;DESCRIPTION OF THE PREFERRED MODALITIES It has been conceptualized that if (1) the organic halide RMi-X resulting from an ATRA reaction is sufficiently reactive towards the transition metal Mtn and (2) the alkene monomer is in excess, a number or sequence of atom transfer radical additions (ie, a possible polymerization of "livingVoltrolled" radical) can occur.Analogy to ATRA, the new current radical polymerization process has been called "polymerization of atom transfer radical ( or group) "(or" ATRP "), which describes the involvement of (1) the atom or group transfer path and (2) a radical intermediary.The living / controlled polymerization (that is, when the reactions that break chains such as transfer and termination are substantially absent) allows the control of various parameters of macromolecular structure such as molecular weight, molecular weight distribution and function terminalities. It also allows the preparation of several copolymers, including block and star copolymers. The polymerization of living / controlled radical requires a low stationary concentration of radicals, in equilibrium with several latent species. In the context of the present invention, the term "controlled" refers to the ability to produce a product having one or more properties, which are reasonably close to their predicted value (assuming a particular initiator efficiency). For example, if one assumes 100% initiator efficiency, the molar ratio of catalyst to monomer leads to a particular predicted molecular weight. The polymerization is said to be "controlled" if the resulting number average molecular weight (Mw (act)) is reasonably close to the predicted number average molecular weight (Mw (pred)); for example, within an order of magnitude, preferably within a factor of four, more preferably within a factor of three and most preferably within a factor of two (ie, Mw (act) is in the range from ( 0.1) x Mw (pred) at 10 x Mw (pred), preferably from (0.25) x Mw (pred) to 4 x Mw (pred), more preferably from (0.5) x Mw (pred) to 2 x Mw (pred) pred), and most preferably from (0.8) x Mw (pred) to 1.2 x Mw (pred) Similarly, one can "control" polydispersity by ensuring that the deactivation rate is the same as or greater than the initial velocity However, the importance of the relative deactivation / propagation velocities decreases proportionally as the polymer chain length increases and / or the predicted molecular weight or degree of polymerization increases The present invention describes the use of novel initiator systems which lead to the polymerization of living / controlled radical. n it is based on the reversible formation of growing radicals in a redox reaction between various transition metal compounds and an initiator, exemplified by (but not limited to) alkyl halides, aralkyl halides or haloalkyl esters. Using 1-phenylethyl chloride (1-PEI) as a model initiator, CuCl as a model catalyst and bipyridine (Bpy) as a model ligand, a bulk polymerization of "living" styrene radical at 130 ° C provides the molecular weight predicted up to Mn <10s with a narrower molecular weight distribution (for example, Mw / Mn < 1.5). A key factor of the present invention is to achieve a rapid exchange between the growing radicals present at low stationary concentrations (in the range from 10"9 mol / la 10" 5 mol / l, preferably 10 * 8 mol / I to 10"5 mol / l) and latent chains present at higher concentrations (typically in the range of 10" 4 mol / la 3 mol / l, preferably 10'2 mol / la 10"1 mol / l) It may be desirable" equalizing "the initiator / catalyst / ligand system and the monomer (s) so that these concentration ranges are reached." Although these concentration ranges are not essential for conducting the polymerization, certain disadvantageous effects may result if the concentration ranges are exceeded. For example, if the concentration of growth radicals exceeds 10"5 mol / l, too many active species may exist in the reaction, which may lead to an undesirable increase in the rate of lateral reactions (eg radical-radical suppression). , radical abstraction of different species to the catalyst system, etc.). If the concentration of growing radicals is less than 10"9 mol / l, the speed may be undesirably slow, however, these considerations are based on the assumption that only free radicals are present in the reaction system. some radicals are in a caged form, the reactivities of which, especially in termination-deactivation reactions, may differ from those of free radicals without caging.
Similarly, if the concentration of latent chains is less than 10"4 mol / l, the molecular weight of the product polymer can increase dramatically, thus leading to a loss of potential for controlling the molecular weight and polydispersity of the product. On the other hand, if the concentration of dormant species is greater than 3 mol / l, the molecular weight of the product may become too small, and the properties of the product may more closely resemble the properties of the oligomers. (However, the oligomeric products they are useful, and are intended to be included within the scope of the invention.) For example, in bulk, a concentration of latent chains from about 10"2 mol / L provides product having a molecular weight of about 100,000 g / mol. On the other hand, a concentration of latent chains exceeding 1 M leads to the formation of (approximately) less than decameric products, and a concentration of about 3 M leads to the formation of trimers (predominantly). In the application with serial No. 08 / 414,415 (incorporated herein by reference in its entirety), a method for preparing a (co) polymer by ATRP is described, which comprises: polymerizing one or more polymerizable monomers by means of radical in the presence of an initiator having an atom or group transferable by radical, a transition metal compound and a ligand to form a (co) polymer, the transition metal compound being capable of participating in a redox cycle with the initiator and a latent polymer chain, and the ligand being any compound containing N-, O-, P- or S-, which can coordinate in a s-ligature to the transition metal, or any compound containing carbon which it can coordinate in a p-ligature to the transition metal, so that direct ligatures between the transition metal and the growing polymer radicals are not formed, and isolate the formed (co) polymer. The present invention includes the following: (1) an ATRP process in which the improvement comprises polymerizing in the presence of a corresponding amount of the corresponding oxidized or reduced transition metal compound, which deactivates at least some free radicals; (2) an ARTP process in which the improvement comprises polymerizing in a homogeneous system or in the presence of a solubilized catalyst / initiator system; (3) functional, site-specific and telechelic terminal functional and homopolymers (see Fig. 1); (4) block, random, graft, alternating and tapered (or "gradient") copolymers, which may have certain properties or a certain structure (for example, a copolymer of alternating receptor and alternating donors, such as the copolymer of isobutylene radical and a (meth) acrylate ester, see Fig. 1); (5) copolymers and star, comb and dendritic (or "hyperbranched") polymers (see Fig. 1); (6) terminal and / or multi-functional functional hyperbranched polymers (see Fig. 1);(7) cross-linked polymers and gels; (8) Water soluble polymers and new hydrogels (eg, copolymers prepared by radical polymerization, comprising a water-soluble backbone and well-defined hydrophobic (co) polymer chains grafted thereon); Y(9) an ATRP process using water as a means. In one embodiment, the present invention concerns improved polymerization methods of atom or group transfer radical, in which a proportion (eg, 0.1-99.9 mol%, preferably 0.2-10 mol% and more preferably 0.5-5% mol) of the transition metal catalyst is in an oxidized or reduced state, relative to the mass of the transition metal catalyst. The oxidized or reduced transition metal catalyst is the redox conjugate of the primary transition metal catalyst; that is, for the redox cycle Mtp +: Mtm +, 90-99.9% mole of transition metal atoms Mt may be in the oxidation state n + and 0.1-10 mole of the transition metal atoms Mt may be in the m + oxidation state. The term "redox conjugate" thus refers to the corresponding oxidized or reduced form of the transition metal catalyst. The oxidation states n and m are reached by the transition metal Mt as a consequence of the ATRP being conducted. The present inventors have found that a sufficient amount of redox conjugate to deactivate at least some of the radicals, which can be formed at the beginning of the polymerization (for example, the product of self-initiation or addition of a radical initiator or chain radical of growing polymer to a monomer) greatly improves the polydispersity and control of the molecular weight of the product . The effects and importance of the exchange rates between the growing species of different reactivities and lives, in relation to the speed of propagation, have not been sufficiently explored in previous work by others, but it has been found by the present Inventors that it has a tremendous effect on polydispersity and molecular weight control in living / controlled polymerizations. As shown in Figure 2, both conventional and controlled polymerizations comprise reactions of initiating radicals with monomer at a constant of velocity kj, propagation of growing chains with monomer at a constant of velocity kp, and termination by coupling and / or disproportionation with an average speed constant kt. In both systems, the concentration of radicals at any given time (the momentary concentration of growing radicals, or [P "] o) is relatively low, approximately 10" 7 mol / l or less. However, in the conventional radical polymerization, the initiator is consumed very slowly (kdec «10" s ± 1 s "1). Additionally, in the conventional radical polymerization, the half-life of the initiator is generally in the range of hours, meaning that a significant proportion of initiator remains unreacted, even after the monomer is completely consumed. In contrast, in controlled polymerization systems, the initiator is consumed for a long time at low monomer conversion (for example, 90% or more initiator can be consumed at at least 10% monomer conversion). In ATRP, the growing radicals are in dynamic equilibrium with latent covalent species. The covalent RX and PX ligatures (initiator and latent polymer, respectively) are homolytically cut to form initiation (R ") or propagation (P") radicals and the corresponding counter-radicals X "The equilibrium position defines the momentary concentration of the growing radicals, polymerization rate and termination contribution Equilibrium dynamics also affects the polydispersity and molecular weight of the polymer as a function of monomer conversion.A model study has been performed on the polymerization of methyl acrylate. at 100 ° C, based on the numerical integration using a Galerkin method described (Predici program) In this study, the propagation velocity constants (kp = 7 x 10"3 mol" 1 I s "1) and termination ( kt = 107 mol "1 I s" 1) were based on available data from published literature. The rate constants of activation and deactivation of the initiator system 1-phenylethyl chloride / CuCI / 2,2'-bipyridyl were then varied by five orders of magnitude, maintaining a value of equilibrium constant K = 10"8. As a result From this model study, it was found that the addition of 1% Cu (ll) (redox conjugate) dramatically improves the polydispersity of, and provides predictable molecular weights for, the (co) polymer products obtained.
The equilibrium constant (that is, the ratio of the activation rate constant ka to the deactivation rate constant kd) can be estimated from known concentrations of radicals, covalent alkyl halides, activator and deactivator according to the equation : K = ka / kd = ([CU "] [P -]) / ([CU,] [I] O)The simulations were performed for bulk polymerization of methyl acrylate ([M] 0 = 1 1 M) or styrene ([M] 0 = 9 M) using an initiator system containing 1-PECI ([l] 0 = 0.1 M) , a 2,2'-bipyridyl / CuCI complex ([Cu '] 0 = 0.1 M) and either 1% or 0% Cu "as an initial deactivator ([Cu"] 0 = 0.001 M or 0 M). The stationary concentration of radicals is approximately 10"7 M, leading to the result that K is approximately 10" 8. After initiation into the system without Cu (ll), the momentary concentration of radicals is reduced from 8 x 10"7 M to 10% conversion to 3.3 x 10" 7 M at 50% conversion and 1.6 x 10"7 M to 90% conversion." At the same time, the concentration of deactivator (Cu ") increases from 1.2 x 10" 4 M to 10% conversion to 3 x 10"4 M at 50% conversion and 6 x 10 '4 M to 90% conversion. The deactivator concentration corresponds to the concentration of finished chains, which at 90% monomer conversion, is only about 0.6% of all the chains generated from the initiator. In the presence of 1% deactivator (redox conjugate), an almost constant concentration of growing radicals is predicted. The momentary concentration of polymer radicals is much more constant in the presence of 1% deactivator, going from 0.98 x 10"7 M to 10% conversion to 0.94 x 10" 7 M at 50% conversion and 0.86 x 10" 7 M to 905 conversion At the same time, the deactivator concentration increases from 1.01 x 10"3 M to 10% conversion to 1.05 x 10" 3 M at 50% conversion and 1.15 x 10"3 M to 90% conversion. The concentration of finished chains corresponds to the increase in deactivator concentration although the initial concentration, which translates to 0.15% of all chains being terminated at 90% conversion. The dynamics of exchange have no effect on the kinetics in the range studied of the values of ka and kd. However, the dynamics have a tremendous effect on molecular weights and polydispersities. In the absence of deactivator in the model systems studied, a degree of polymerization (DPn) from approximately 90 is expected. However, if deactivation is slow, very high molecular weights are initially observed. As the conversion increases, the molecular weights slowly begin to coincide with predicted values. The initial discrepancy has a tremendous effect on polydispersities, as will be discussed later. If the deactivation is sufficiently fast (in the model system, approximately 107 mol "1 I s" 1), the predicted and observed molecular weights are in substantial agreement of the polymerization initiation. However, when deactivation is slow, the initial DP is substantially greater than predicted (DP = 60 when kd = 106 M "1 s" 1, and DP = 630 when kd = 105 M "1 s" 1). In this way, the initial values of DP can be predicted by the ratio of velocities of propagation to deactivation by means of the equation:DP = Rp / Rd = kp [M] 0 [P -] / kd [Cu "] or [P"]However, with respect to the deactivation rate, the initial polydispersities are much higher than those predicted for a Poisson distribution. However, if deactivation is fast enough, at full conversion, very narrow polydispersities (Mw / Mn) are observed (eg, less than 1.1). On the other hand, if the deactivation velocity is approximately the same as the termination velocity (in the case of the model, approximately 107 M "1 s" 1), then the polydispersity at full conversion is approximately 1.5. When deactivation is approximately three times smaller, the polydispersity at full conversion is approximately 2.5. However, in the presence of 1% deactivator, a deactivation velocity which is approximately the same as the termination rate, results in a near ideal polydispersity (<; 1.1) at full conversion, although initially, it is quite high (approximately 2), decreasing to approximately 1.5 to 25% conversion and < 1.2 to 75% conversion. Where deactivation is slowest (kd = 106), the final polydispersity is 1 .7. A small amount of deactivator (redox conjugate) is sufficient to trap or quench the free radicals formed during polymerization. A large excess of redox conjugate is not necessary, although it does not have an adverse or continuous effect on the polymerization rate. It is noted that an average termination speed constant kt = 10"7 M" 1 s "1 was used, however, the current termination rate constant depends strongly on the chain length, for monomeric radicals, it can be so high as 109 M "1 s'1, but for very long chains, it can be as low as 102 M" 1 s "1. An important difference between controlled polymerization and conventional radical polymerization is that almost all chains have similar chain length in controlled polymerization, while new radicals are continuously generated in conventional radical polymerization. Therefore, in substantial conversion, the long chain radicals do not react with each other, but rather, with radicals of low molecular mass newly generated in the conventional polymerization. In controlled systems, in contrast, after a certain chain length has been reached, the reaction mixture becomes more viscous, and the current rate of termination constant can drop dramatically, thus improving the polymerization control to a degree greater than what one would have predicted before the present invention. The addition of a redox conjugate to ATRP also increases the control of molecular weight and polydispersities by expelling radicals formed by other processes, such as thermal self-initiation of monomer. For example, in the model systems studied, CuCI2 acts as a polymerization inhibitor, and expels polymer chains at an early stage, preventing the formation of a higher molecular weight polymer, which can be formed by thermal auto-initiation. It has been observed by the present Inventors that the polymerization rate is not affected in a linear manner by the amount or concentration of the deactivating agent (redox conjugate). For example, the presence of 5 mol% redox conjugate can be expected to decrease the polymerization rate 10 times relative to 0.5 mol% redox conjugate. However, 5 mol% of redox conjugate actually lowers the polymerization rate by an amount significantly less than 10 times relative to 0.5 mol% of redox conjugate. Although an accurate explanation for this phenomenon is not yet available, it is believed that many radicals generated by the present initiator / transition metal compound / ATRP ligand can be protected by a solvent / monomer "cage". Thus, the presence of more than 10 mol% of redox conjugate does not adversely affect polymerization by ATRP, although it may decrease the polymerization rate to a small degree. Experimental observations also support the idea that large amounts of redox conjugate are not harmful to polymerization, a result that is surprising in view of the observations that redox conjugates adversely affect ATRA. For example, in the heterogeneous ATRP of acrylates using copper (I) chloride, the color of the catalyst changes from red (Cu1) to green (Cu "). However, the apparent rate constant of polymerization is essentially constant, or at least it does not decrease significantly.
As described above, the redox conjugate is present in an amount sufficient to deactivate at least some of the initially formed initiator-monomer adduct radicals, thermal auto-initiation radicals and subsequently formed polymer radicals. A key to achieving narrow polydispersities is to control the polymerization reaction parameters such that the rate of radical deactivation is approximately the same as or greater than the propagation velocity. In one embodiment, the improvement for the method comprises adding the transition metal redox conjugate to the reaction mixture before polymerizing. Alternatively, when the transition metal compound is commercially available as a mixture with its redox conjugate (e.g., many commercially available Cu (l) salts contain 1-2 mol% of Cu (II)), the process is improved it comprises adding the transition metal compound to the polymerization reaction mixture without purification. In an alternative embodiment, the improved ATRP method comprises exposing the transition metal compound to oxygen for a length of time before polymerizing the monomer (s). In preferred embodiments, the oxygen source is air, and the length of time is sufficient to provide 0.1 to 10 mol% of the redox conjugate of the transition metal compound. This embodiment is particularly suitable when the transition metal is a compound of Cu (I), such as CuCl or CuBr.
One can also conduct an "inverse" ATRP, in which the transition metal compound is in its oxidized state, and the polymerization is initiated by, for example, a radical initiator such as azobis (isobutyronitrile) ("AIBN") , a peroxide such as benzoyl peroxide (BPO) or a peroxy acid such as peroxyacetic acid or peroxybenzoic acid. The radical initiator is believed to initiate an "inverse" ATRP in the following manner:l-l > 2 I "I" + Mtn + 1Xn "? T * lX + MtpXn-? I" + M lM-lM "+ M, n + 1X" ^ _? IMX + MtnXn.? LM "+ n M 9l-Mn +? "I- Mn + 1 + Mtn + 1X" ^ Z_? I- Mn + 1-X + MtnXn-?where "I" is the initiator, MtnXn-? is the transition metal compound, M is the monomer, e-M-X and MtnXp-? participates in "conventional" or "advanced" ATRP in the manner described above. After the polymerization step is complete, the polymer formed is isolated. The isolation step of the present process is conducted by known methods, and may comprise evaporating any residual monomer and / or solvent, precipitating in a suitable solvent, filtering or centrifuging the precipitated polymer, washing the polymer and drying the washed polymer. The transition metal compounds can be removed by passing a mixture containing them through a column or cushion of alumina, silica and / or clay. Alternatively, the transition metal compounds can be oxidized (if necessary) and retained in the (co) polymer as a stabilizer. The precipitation can typically be conducted using a C5-C8-alkane or C5-C8-cycloalkane solvent, such as pentane, hexane, heptane, cyclohexane or mineral essences, or using a d-C6-alcohol, such as methanol, ethanol or isopropanol, or any mixture of suitable solvents. Preferably, the solvent for precipitating is water, hexane, mixtures of hexanes or methanol. The precipitated (co) polymer can be filtered by gravity or by vacuum filtration, according to known methods (for example, using a Büchner funnel and a vacuum cleaner). Alternatively, the precipitated (co) polymer can be centrifuged and the supernatant liquid decanted to isolate the (co) polymer, if desired. The steps of precipitating and / or centrifuging, filtering and washing can be repeated, as desired. Once isolated, the (co) polymer can be dried by entraining air through the (co) polymer, by vacuum, etc. , according to known methods (preferably by vacuum). The present (co) polymer can be analyzed and / or characterized by size exclusion chromatography, NMR spectroscopy, etc. , according to known procedures. The various initiator systems of the present invention work for any polymerizable alkene by radical, including (meth) acrylates, styrenes and dienes. It also provides various controlled copolymers, including (co) block, random, alternating, gradient, star, graft or "comb", and hyperbranched and / or dendritic (co) polymers. (In the present application, "(co) polymer" refers to a homopolymer, copolymer or mixture thereof.) Similar systems have previously been used in organic synthesis, but have not been used for the preparation of well-defined macromolecular compounds. In the present invention, any radically polymerizable alkene can serve as a monomer for polymerization. However, monomers suitable for polymerization in the present method include those of the formula:R1 R-1 \ / C = C / \ R2 R4wherein R1 and R2 are independently selected from the group consisting of H, halogen, CN, linear or branched alkyl of 1 to 20 carbon atoms (preferably 1 to 6 carbon atoms, more preferably 1 to 4 carbon atoms) ), which can be substituted with from 1 to (2n + 1) halogen atoms, where n is the number of carbon atoms of the alkyl group (for example, CF3), ß-alkenyl or unsaturated linear or branched alkynyl of 2 to 10 carbon atoms (preferably 2 to 6 carbon atoms, more preferably 2 to 4 carbon atoms), which may be substituted with 1 to (2n-1) halogen atoms (preferably chlorine) , where n is the number of carbon atoms of the alkyl group (for example CH2 = CCI-), C3-C8 cycloalkyl, which may be substituted with 1 to (2n-1) halogen atoms (preferably chlorine), where n is the number of carbon atoms of the cycloalkyl group, C (= Y) R5, C (= Y) NR6R7, YC (= Y) RS, SOR5, SO2R5, OSO2R5, NR8SO2R5, PR52, P (= Y) RS2, YPR52, YP (= Y) RS2, NR82 which can be quaternized with an additional R8 group, aryl and heterocyclyl; where Y can be NR8, S or O (preferably O); Rs is alkyl from 1 to 20 carbon atoms, alkylthio from 1 to 20 carbon atoms, OR24 (where R24 is H or an alkali metal), alkoxy from 1 to 20 carbon atoms, alkoxy from 1 to 20 carbon atoms, aryloxy or heterocyclicloxy; R6 and R7 are independently H or alkyl from 1 to 20 carbon atoms, or R6 and R7 can be linked to form an alkylene group from 2 to 7 (preferably 2 to 5) carbon atoms, thereby forming a ring of 3 to 8 members (preferably 3 to 6 members), and R8 is H, aryl or straight or branched C1-C20 alkyl; R3 and R4 are independently selected from the group consisting of H, halogen (preferably fluorine or chlorine), C6-C6 alkyl (preferably d) and COOR9 (where R9 is H, an alkali metal or an alkyl group of d). -C6), or R1 and R3 can be joined to form a group of the formula (CH2) p- (which can be substituted with 1 to 2'alcogen atoms or alkyl groups of dC) or C (= O) -YC (= O), where n 'is from 2 to 6 (preferably 3 or 4) and Y is as defined above; and at least two of R1, R2, R3 and R4 are H or halogen.
In the context of the present application, the terms "alkyl", "alkenyl" and "alkynyl" refer to straight or branched chain groups (except for groups C, and C2). The "alkenyl" and "alkynyl" groups may have sites of unsaturation at any position or positions of adjacent carbon atom provided that the carbon atoms remain tetravalent, but are preferred at, β- or terminal (i.e., at the? Positions. - y (? -1)). Additionally, in the present application, "aryl" refers to phenyl, naphthyl, phenanthryl, phenalenyl, anthracenyl, triphenylenyl, fluorantenyl, pyrenyl, pentacenyl, chrysanil, naphthacenyl, hexaphenyl, phenyl and perylenyl (preferably phenyl and naphthyl), wherein each hydrogen atom can be replaced with halogen, alkyl from 1 to 20 carbon atoms (preferably from 1 to 6 carbon atoms and more preferably methyl) in which each of the hydrogen atoms can be independently replaced by a group X as defined above (for example, a halide, preferably a chloride or a bromide), alkenylene or alkynyl from 2 to 20 carbon atoms in which each of the hydrogen atoms can be independently replaced by a group X as it was defined before (for example, a halide, preferably a chloride or a bromide), alkoxy from 1 to 6 carbon atoms, alkylthio from 1 to 6 carbon atoms, cycloalkyl of d-C8 in Which one of the hydrogen atoms can be independently replaced by a group X as defined above (for example, a halide, preferably a chloride or a bromide), phenyl, N H2 or d-C6-alkylamino or d-? C6-dialkylamino, which can be quaternized with a group R8, COR5, OC (= O) R5, SOR5, SO2R5, OSO2R5, PR52, POR52 and phenyl which can be substituted with from 1 to 5 halogen atoms and / or C -C4 alkyl groups. (This definition of "aryl" also applies to the aryl groups in "aryloxy" and "aralkyl".) Thus, the phenyl can be substituted 1 to 5 times and the naphthyl can be substituted 1 to 7 times (preferably, any aryl group, if substituted, is substituted 1 to 3 times) with one or more of the above substituents.More preferably, "aryl" refers to phenyl, naphthyl, phenyl substituted from 1 to 5 times with fluorine or chlorine, and phenyl substituted 1 to 3 times with a substituent selected from the group consisting of alkyl of 1 to 6 carbon atoms, alkoxy of 1 to 4 carbon atoms and phenyl, most preferably, "aryl" refers to phenyl, tolyl, a-chlorotolyl, a-bromotolyl and methoxyphenyl.
In the context of the present invention, "heterocyclyl" refers to pyridyl, furyl, pyrrolyl, thienyl, imidazolyl, pyrazolyl, pyrazinyl, pyrimidinyl, pyridazinyl, pyranyl, indolyl, isoindolyl, indazolyl, benzofuryl, isobenzofuryl, benzothienyl, isobenzothienyl, chromenyl, xanthenyl, purinyl, pteridinyl, quinolyl, isoquinolyl, phthalazinyl, quinazolinyl, quinoxalinyl, naphthyridinyl, phenoxythinyl, carbazolyl, cinolinyl, phenanthridinyl, acridinyl, 1, 10-phenanthrolinyl, phenazinyl, phenoxazinyl, phenothiazinyl, oxazolyl, thiazolyl, isoxazolyl, isothiazolinium, and hydrogenated thereof known to those in the art. Preferred heterocyclyl groups include pyridyl, furyl, pyrrolyl, thienyl, imidazolyl, pyrazolyl, pyrazinyl, pyrimidinyl, pyridazinyl, pyranyl and indolyl, with the heterocyclyl group being more preferred pyridyl. Accordingly, suitable vinyl heterocycles to be used as a monomer in the present invention include 2-vinyl pyridine, 4-vinyl pyridine, 2-vinyl pyrro !, 3-vinyl pyrrole, 2-vinyl oxazole, 4-vinyl. oxazole, 2-vinyl thiazole, 4-vinyl thiazole, 2-vinyl imidazole, 4-vinyl imidazole, 3-vinyl pyrazole, 4-vinyl pyrazole, 3-vinyl pyridazine, 4-vinyl pyridazine, 3-vinyl isoxazole, 4-vinyl isoxazole, 3-vinyl isothiazole, 4-vinyl isothiazole, 2-vinyl pyrimidine, 4-vinyl pyrimidine, 5-vinyl pyrimidine, and 2-vinyl pyrazine, with 2-vinyl pyridine being most preferred. The vinyl heterocycles mentioned above can support one or more substituents as defined above by an "aryl" group (preferably 1 or 2) in which each H atom can be replaced independently, for example, with C alquilo alkyl group C6, d-C6 alkoxy groups, cyano groups, ester groups or halogen atoms, either in the vinyl group or the heterocyclyl group, but preferably in the heterocyclyl group. In addition, those vinyl heterocycles which, when unsubstituted, contain an N atom that can be quaternized with a R8 group (as defined above), and those which contain an NH group can be protected at that position with a protecting group or conventional blocker, such as a C? -C6 alkyl group, a tris- (C? -C6 alkyl) silyl group, an acyl group of the formula R10CO (where R10 is alkyl of 1 to 20 carbon atoms in which each of the hydrogen atoms can be replaced independently by halide [preferably fluoride or chloride]), alkenyl of 2 to 20 carbon atoms (preferably vinyl,), alkynyl of 2 to 10 carbon atoms (preferably acetylenyl), phenyl which can be substituted with 1 to 5 halogen atoms or alkyl groups of 1 to 4 carbon atoms, or aralkyl (alkyl substituted with aryl, in which the aryl group is phenyl or substituted phenyl and the alkyl group is 1 to 6 carbon atoms, such as benciio), etc. This definition of "heterocyclyl" also applies to the heterocyclyl groups in "heterocyclyloxy" and "heterocyclic ring". More specifically, preferred monomers include C 3 -C 2 α-olefins, isobutene, (meth) acrylic acid and alkali metal salts thereof, (meth) acrylate esters of C?-C2o alcohols > acrylonitrile, acrylamide, cyanoacrylate esters of C? -C20 alcohols, didehydromalonate diesters of d-C? alcohols, vinyl pyridines, vinyl N-Ci-Ce-alkyl pyrroles, N-vinyl pyrrolidones, vinyl oxazoles, vinyl thiazoles, vinyl pyrimidines , vinyl imidazoles, vinyl ketones in which the a-carbon atom of the alkyl group does not support a hydrogen atom (for example, vinyl dd-alkyl ketones in which both a-hydrogens are replaced with C? -C alkyl, halogen , etc., or a vinyl phenyl ketone in which the phenyl can be substituted with 1 to 5 Ci-Cs-alkyl groups and / or halogen atoms), and styrenes, which can support a Ci-C6-alkyl group in the vinyl portion (preferably at the α-carbon atom) and from 1 to 5 (preferably from 1 to 3) substituents on the phenyl ring selected from the group consisting of d-Ce-alkyl, Ci-Ce-alkenyl (preferably vinyl), d-C6-alkynyl (preferably acetylenyl), C? -C6-alkoxy, halogen, nitro, carboxy, Ci-Ce-alkoxycarbonyl, hydroxy protected with a C? -C6 -acyl, SO2R5, cyano and phenyl. The most preferred monomers are isobutene, N-vinyl pyrrolidone, methyl acrylate (MA), methyl methacrylate (MMA), butyl acrylate (BA), 2-ethylhexyl acrylate (EHA), acrylonitrile (AN), styrene (St) and p-tert-butyl styrene.
In the present invention, the initiator can be any compound having one or more atoms or groups, which are transferable by radical under the polymerization conditions. Suitable initiators include those of the formula:R 1R1 R13C-X R11C (= O) -X R11 R12R13Si-X R11 R12N-X R1 1 N-X2(R11) (R12O) P (O) m-Xwhere: X is selected from the group consisting of Cl, Br, I, OR10 (as defined above), SR14, SeR14, OC (= O) R14, OP (= O) R14,, OP (= O) (OR14 ) 2, OP (= O) OR14, ON (R14) 2, SC (= S) N (R14) 2, CN, NC, SCN, CNS, OCN, CNO and N3, where R14 is aryl or a linear alkyl group or branched C1-C20 (preferably C1-C10), or where a group N (R14) 2 is present, the two R14 groups can be joined to form a 5-, 6- or 7-membered heterocyclic ring (according to the definition of "heterocyclyl" above); and R11, R12 and R13 are each independently selected from the group consisting of H, halogen, C? -C20 alkyl (preferably C1-C10 alkyl and more preferably d6C6 alkyl), C3-C8 cycloalkyl, R83Si, C (= Y) R5, C (= Y) NR6R7 (where Rs-R7 are as defined above), COCÍ, OH (preferably only one of R11, R12 and R13 is OH), CN, alkenyl or alkynyl of C2-C2o (preferably C2-C6 alkenyl or alkynyl, and more preferably allyl or vinyl), oxiranyl, glycidyl, alkylene or alkenylene of d-Cβ substituted with oxyranyl or glycidyl, aryl, heterocyclyl, aralkyl, aralkenyl (substituted alkenyl with aryl, where aryl is as defined above, and alkenyl is vinyl, which can be substituted with one or two alkyl groups of d-C6 and / or halogen atoms [preferably chlorine]), d-C6 alkyl in which of 1 to all hydrogen atoms (preferably 1) are replaced with halogen (preferably fluorine or chlorine, where 1 or more atoms of hydrogen are replaced, and preferably fluorine, chlorine or bromine where 1 hydrogen atom is replaced) and substituted C 1 -C 6 alkyl with 1 to 3 substituents (preferably 1) selected from the group consisting of C 1 - alkoxy C, aryl, heterocyclyl, C (= Y) R5 (where R5 is as defined above), C (= Y) NR6R7 (where R6 and R7 are as defined above), oxiranyl and glycidyl; preferably so that no more than two of R1 1, R12 and R13 are H (more preferably not more than one of R11, R12 and R13 is H); m is 0 or 1; and n is 0, 1 or 2. In the present invention, X is preferably Cl or Br. Initiators containing Cl generally provide (1) a slower reaction rate and (2) product polydispersity greater than the initiators containing Br corresponding. However, generally Cl-terminated polymers have higher thermal stability than polymers terminated with corresponding Br. When an alkyl, cycloalkyl or aryl substituted with alkyl group is selected for one of R11, R12 and R13, the alkyl group may be substituted with a group X as defined above. In this way, it is possible for the initiator to serve as a molecule for branched or star (co) polymers. An example of such an initiator is a 2,2-bis (halomethyl) -1,3-dihalopropane (for example, 2,2-bis (chloromethyl) -1,3-dichloropropane, 2,2, -bis (bromomethyl) - 1,3-dibromopropane), and a preferred example is where one of R1, R12 and R13 is phenyl substituted with from 1 to 5 Ci-Cß alkyl substituents, each of which can independently be further substituted with a group X (e.g., a, a'-dibromoxylene, tetrakis- or hexakis (a-chloro- or a-bromomethyl) -benzene). Preferred initiators include 1-phenylethyl chloride and 1-phenylethyl bromide (eg, where R11 = Ph, R12 = CH3, R13 = H and X = Cl or Br), chloroform, carbon tetrachloride, 2-chloropropionitrile, esters of C? -C6-alkyl of a 2-halo-C? -C6-carboxylic acid (such as 2-chloropropionic acid, 2-bromopropionic acid, 2-chloroisobutyric acid, 2-bromoisoburitic acid, etc.), p-halomethylstyrenes and compounds of the formula C6Hx (CH2X) and CXx [(CH2) n (CH2X)] and, where X is Cl or Br, x + y = 6, x '+ y' = 4, 0 <; n < 5 and so much and 'as and < 1 . More preferred initiators include 1-phenylethyl chloride, 1-phenylethyl bromide, methyl 2-cyoropropionate, ethyl 2-chloropropionate, methyl 2-bromopropionate, ethyl 2-bromoisobutyrate, p-chloromethylstyrene, a, a'-dichloroxy- ene, a, a'-dibromoxylene and hexakis (a-bromomethyl) benzene. A transition metal compound, which can participate in a redox cycle with the initiator and the latent polymer chain, is suitable for use in the present invention. Preferred transition metal compounds are those that do not form a direct carbon-metal bond with the polymer chain. Particularly, the transition metal compounds are those of the formula Mtp + X'n, where: Mtn + may be, for example, selected from the group consisting of Cu 1+, Cu 2+, Au +, Au 2+, Au 3+, Ag +, Ag 2 +, Hg + , Hg2 +, Ni0, Ni +, Ni2 +, Ni3 +, Pd ° Pd +, Pd2 +, Pt °, Pt +, Pt + 2, Pt + 3, Pt + 4, Rh +, Rh2 +, Rh3 +, Rh4 +, Co +, Co2 +, Co3 + Ir0, lr + , LR2 +, LR3 +, LR4 +, Fe2 +, Fe3 +, Ru2 +, Ru3 +, Ru4 +, Rus +, Ru6 +, Os2 +, Os3 + Os4 +, Re2 +, Re3X Re4 +, Re6 +, Re7 +, Mn2 +, Mn3X Mn4X Cr2X Cr3 +, Mo °, Mo + Mo2 +, Mo3 +, W2 +, W3 +, V2 +, V3 +, V4 +, V5 +, Nb +, Nb + 3, Nb4 +, Nb5 +, Ta3 +, Ta4 + Tas +, Zn + and Zn2 +; X 'can be, for example, selected from the group consisting of halogen, OH, (O) 1/2, d-C6-alkoxy, (SO4) 1/2, (PO4) 1/3, (HPO4) 1 / 2, (H2PO4), triflate, hexafiuorophosphate, methanesulfonate, arylsulfonate (preferably benzenesulfonate or toluenesulfonate), SeR14, CN, CN, SCN, CNS, OCN, CNO, N3 and R15CO2, where R14 is as defined above and R15 is H or a linear or branched C.sub.C.sub.Ce group (preferably methyl) or aryl (preferably phenyl), which can be substituted 1 to 5 times with a halogen (preferably 1 to 3 times with fluorine or chlorine); and n is the formal charge on the metal (for example, 0 <n <7).
Ligands suitable for use in the present invention include compounds having one or more nitrogen, oxygen, phosphorus and / or sulfur atoms, which can coordinate to the transition metal through a s-ligation, ligands containing two or more carbon atoms which can coordinate the transition metal through a p-ligation, the ligands that have a carbon atom which can coordinate the transition metal through a s-ligature, but which do not form a ligature carbon-carbon with the monomer under the conditions of the polymerization step (for example, ligands that do not participate in the reaction of β-addition with monomers (coordinated), see, for example, the ligand (s) described by van de Kuil et al. al., and van Koten et al., Red., Chim. Pays-Bas, 1 13, 267-277 (1994)), and ligands which can coordinate the transition metal through a μ-ligature or a ?-ligature. Ligands containing N-, O-, P- and S-preferred may have one of the following formulas:R16-Z-R17 or R • 1160-Z -7- (DR1180-Z -7) \ m- rR-, 11 7wherein: R 16 and R 17 are independently selected from the group consisting of H, C 1-4 alkyl, aryl, heterocyclyl, and C? -C6 alkyl substituted with d-C6 alkoxy, C1-C dialkylamino, C (= Y ) RS, C (= Y) R6R7 and / or YC (= Y) R8, where Y, R5, R6, R7 and R8 are as defined above; or R16 and R17 can be joined to form a saturated, unsaturated or heterocyclic ring as described above for the "heterocyclyl" group; Z is O, S, NR19 or PR19, where R19 is selected from the same group as R16 and R17, each R18 is independently a divalent group selected from the group consisting of C2-C alkylene (alkanediyl) and C2-C alkenylene, wherein the Covalent ligatures for each Z are in adjacent positions (eg, in a 1, 2-array) or in β-positions (eg, in a 1, 3-array) and C3-C8 cycloalkanediyl, C3-C8 cycloalkennediyl, arenodiyl , and heterocyclylene, where the covalent bonds for each Z are in adjacent positions; and M is from 1 to 6. In addition to the above ligations, each of R 6 -Z and R 17 -Z can form a ring with the group R 18 for which Z is linked to form a linked or fused heterocyclic ring system ( as described above for "heterocyclyl"). Alternatively, when R16 and / or R17 are heterocyclyl, Z may be a covalent bond (which may be single or double), CH2 or a ring of 4 to 7 members fused to R16 and / or R17, in addition to the definitions given above for Z. Exemplary ring systems for the present linkage include bipyridyl, bipyrrole, 1, 10-phenanthroline, a cryptan, a crown ether, etc. Where Z is PR19, R19 can also be C? -C20-alkoxy.
Also included as suitable ligands in the present invention are CO (carbon monoxide), porphyrins and porphycenes, the last two of which may be substituted with from 1 to 6 (preferably 1 to 4) halogen atoms, alkyl groups of C? -C6, Ci-Cβ-aikoxy, C? -C6-alkoxycarbonyl groups, aryl groups, heterocyclyl groups, and C1-C6 alkyl groups further substituted with from 1 to 3 halogens. In addition, ligands suitable for use in the present invention include compounds of the formula R20R21C (C (= Y) R5) 2, where Y and R5 are as defined above, and each of R20 and R2 is independently selected from the group consisting of H, halogen, Ci-C20 alkyl, aryl and heterocyclyl, R20 and R21 may be joined to form a C3-C8 cycloalkyl ring or a hydrogenated (ie, reduced, non-aromatic or partially aromatic heterocyclic or aromatic ring) completely saturated) (consistent with the definitions of "aryl" and "heterocyclyl" above), any of which (except for H and halogen) can be further substituted with 1 to 5 and preferably 1 to 3 Ci-Cß alkyl groups C6-C6 alkoxy groups, halogen atoms and / or aryl groups. Preferably, one of R20 and R21 is H or a negative charge. Additional suitable ligands include, for example, etiiendiamine and propylene diamine, both can be substituted one to four times at the amino nitrogen atom with a C? -C alkyl group or a carboxymethyl group; aminoethanol and aminopropane, both of which can be substituted one to three times on the oxygen and / or nitrogen atom with an alkyl group of C, -C4; ethylene glycol and propylene glycol, both of which can be substituted one to two times in the oxygen atoms with an alkyl group of C? -C; diglyme, triglyme, tetraglime, etc. Suitable carbon-based ligands include ares (as described above for the "aryl" group) and the cyclopentadienyl ligand. Preferred carbon-based ligands include benzene (which can be substituted with from one to six C-C alkyl groups [eg, methyl]) and cyclopentadienyl (which can be substituted with from one to five methyl groups, or which may be linked through a chain of ethylene or propylene to a second cyclopentadienyl ligand). Where the cyclopentadienyl ligand is used, it may not be necessary to include a counter-anion (X ') in the transition metal compound. Preferred ligands include unsubstituted and substituted pyridines and bipyridines (wherein substituted pyridines and bipyridines are as described above for "heterocyclyl"), acetonitrile, (R10O) 3P, PR103, 1, 10-phenanthroline, porphyrin, cryptans such as K222 and crown ethers such as 18-crown-6. The most preferred ligands are bipyridyl, 4,4'-dialkyl-bipyridyls and (R10O) 3P. A preformed transition metal-ligand complex can be used in place of a mixture of transition metal compound and ligand without affecting the polymerization behavior. The present invention also concerns an improved atom or group transfer polymerization process employing a solubilized catalyst, which in a preferred embodiment results in a homogeneous polymerization system. In this embodiment, the method employs a ligand having substituents that render the transition metal-ligand complex at least partially soluble, preferably more soluble than the corresponding complex in which the ligand does not contain the substituents, and more preferably, at least 90 to 99% soluble in the reaction medium. In this embodiment, the ligand may have one of the formulas R16-Z-R17, R16-Z- (R18-Z) -R17 or R20R21C (C (= Y) R5) 2 above, wherein at least one of R16 and R17 or at least one of R20 and R21 are C2-C20 alkyl, d-C6 alkyl substituted with d-C6 alkoxy and / or C? -C dialkylamino, or are aryl or heterocyclyl substituted with at least one aliphatic substituent selected from the group consisting of C1-C20 alkyl, C2-C2o alkelene, C2-C2o alkynylene and aryl such that at least two, preferably at least four, more preferably at least six, and most preferably at least eight carbon atoms are members of the aliphatic substituent (s). Particularly preferred ligands for this embodiment of the invention include 2,2'-bipyridyl having at least two alkyl substituents containing a total of at least eight carbon atoms, such as 4,4'-di- (t-noni) !) - 2,2'-bipyridyl (dNbipy), 4,4'-di-n-heptyl-2,2'-bipyridyl (dHbipy) and 4,4'-di-tert-butyl-2,2'- bipyridyl (dTbipy). Particularly, when combined with the aforementioned process to polymerize a monomer in the presence of a small amount of transition metal redox conjugate, a substantial improvement in the polydispersity of the product is observed. While heterogeneous ATRP produces polymers with polydispersities that generally vary from 1.1 to 1.5, the so-called "homogenous ATRP" (eg, based on dNbipy, dHbipy or dTbipy) with present transition metal redox conjugate (eg, Cu (l) / Cu (ll)) produces polymers with polydispersities ranging from less than 1.05 to 1.0. In the present polymerization, the amounts and relative proportions of initiator, transition metal compound and ligand are those effective to conduct ATRP. Initiator efficiencies with the present initiator / transition metal / ligand system are generally very good (eg, at least 25%, preferably at least 50%, more preferably >; 80%, and most preferably > 90%). Accordingly, the amount of initiator can be selected such that the concentration of initiator is 10"4 M to 3 M, preferably 10" 3-10"1 M. Alternatively, the initiator may be present in a molar ratio from 10"4: 1 to 0.5: 1, preferably from 10 * 3: 1 to 5 x 10" 2: 1, relative to the monomer.A primer concentration of 0.1-1 M is particularly useful for preparing terminal functional polymers. The molar ratio of the transition metal compound relative to the initiator is generally that which is effective to polymerize the selected monomer (s), but can be from 0.0001: 1 to 10: 1, preferably from 0.1: 1 to 5: 1, more preferably from 0.3: 1 to 2: 1, and most preferably from 0.9: 1 to 1.1: 1. Conducting the polymerization in a homogeneous system may allow reducing the concentration of the transition metal and the ligand such that the molar ratio of the compound transition metal to start The designer is as low as 0.001: 1.
Similarly, the molar ratio of ligand to transition metal compound is generally that which is effective to poiimerize the selected monomer (s), but may depend on the number of coordination sites in the transition metal compound which will occupy the selected ligand. (Someone of ordinary skill understands the number of coordination sites in a given transition metal compound, which will occupy a selected ligand). The amount of ligand can be selected so that the ratio of (a) coordination sites in the transition metal compound to (b) coordination sites which the ligand will occupy is from 0.1: 1 to 100: 1, preferably from 0.2: 1 to 10: 1, more preferably from 0.5: 1 to 3: 1, and most preferably from 0.8: 1 to 2: 1. However, as is known in the art, it is possible for a solvent or for a monomer to act as a ligand. For the purposes of this application, however, the monomer is preferably (a) other than y (b) not included within the scope of the ligand, although in some embodiments (e.g., the present process for preparing a (co) polymer of grafting and / or hyperbranching), the monomer can be self-initiating (ie, capable of serving both as an initiator and as a monomer). However, certain monomers, such as acrylonitrile, certain (meth) acrylates and styrene, are capable of serving as ligands in the present invention, independent of or in addition to their use as a monomer. The present polymerization can be conducted in the absence of solvent ("bulk" polymerization). However, when a solvent is used, suitable solvents include ethers, cyclic ethers, C5-C10 alkanes, C3-C8 cycloalkanes which can be substituted with from 1 to 3 C? -C4 alkyl groups, aromatic hydrocarbon solvents , halogenated hydrocarbon solvents, acetonitrile, dimethylformamide, ethylene carbonate, propylene carbonate, dimethisulfoxide, dimethylsulfone, water, mixtures of such solvents and supercritical solvents (such as CO2, C? -C alkanes in which any H can be replaced with F, etc.). The present polymerization can also be conducted according to known processes of suspension, emulsion, mini-emulsion, gas phase, dispersion, precipitation and reactive injection molding polymerization, particularly dispersion and mini-emulsion polymerization processes. Suitable ethers include compounds of the formula R 2 OR 23, in which each of R 22 and R 23 is independently an alkyl group of 1 to 6 carbon atoms or an aryl group (such as phenyl) which can be further substituted with a group dd-alkyl or C? -C4-alkoxy. Preferably, when one of R22 and R23 is methyl, the other of R22 and R23 is alkyl of 4 to 6 carbon atoms, C? -C-alkoxyethyl or p-methoxyphenyl. Examples include diethyl ether, ethyl propyl ether, dipropyl ether, methyl t-butyl ether, di-t-butyl ether, glyme (dimethoxyethane), diglyme (diethylene glycol dimethyl ether), 1,4-dimethoxybenzene, etc. Suitable cyclic ethers include THF and dioxane. Suitable aromatic hydrocarbon solvents include benzene, toluene, o-xylene, m-xylene, p-xylene and mixtures thereof. Suitable halogenated hydrocarbon solvents include CH 2 Cl 2, 1,2-dichloroethane and benzene substituted 1 to 6 times with fluorine and / or chlorine, although preferably the halogenated hydrocarbon solvent (s) selected does not act as an initiator under the conditions of polymerization reaction. ATRP can also be conducted either in bulk or in an aqueous medium to prepare water-soluble or water-miscible polymers. Water-soluble polymers are scientifically and commercially important, because they find a wide range of applications in mineral processing, water treatment, oil recovery, etc. (Bekturov, E.A., Bakauova, Z. K. Synthetic Water-Soluble Polymers in Solution, Huethig and Wpf: Basel, 1986; Molyneux, P. Water-Soluble synthetic Polymers: Properties and Behavior, CRC Press: Boca Raton, Florida, 1991). Many of the industrially important water soluble polymers are prepared by free radical polymerization of vinyl and acrylic monomers, because this polymerization technique is acceptable for use in aqueous solutions (Elias, H., Vohwinkel, F. New Commercial Polymers 2; Gordon and Breach: New York, 1986). For these reasons, it is beneficial to develop well controlled radical polymerizations for use in aqueous polymerizations (Keoshkerian, B., Georges, M.K., Boils-Boissier, D. Macromolecules 1995, 28, 6381). In this way, the present ATRP process can be conducted in an aqueous medium. An "aqueous medium" refers to a mixture containing water which is liquid at reaction and processing temperatures. Examples include water, either alone or mixed with water soluble C? -C alcohol, ethylene glycol, glycerol, acetone, methyl ethyl ketone, dimethylformamide, dimethyl sulfoxide, dimethylsulfone, hexamethylphosphoric triamide, or a mixture thereof. Additionally, the pH of the aqueous medium can be adjusted to a desired value with a suitable mineral acid or base (for example, phosphoric acid, hydrochloric acid, ammonium hydroxide, NaOH, NaHCO3, Na2CO3, etc.). However, the preferred aqueous medium is water. When driving in an aqueous medium, the polymerization temperature can be from 0 ° C to the reflux temperature of the medium, preferably from 20 ° C to 100 ° C and more preferably from 70 ° C to 100 ° C. Preferably, the monomer (s) polymerized in this embodiment are at least partially water soluble or water miscible, or alternatively, capable of being polymerized in an aqueous emulsion, which further comprises a surfactant (preferably in an amount sufficient to emulsify the monomer (s)). Such monomers are preferably sufficiently soluble in water at 80 ° C to provide a monomer concentration of at least 10"2 M, and more preferably 10" 1 M. Suitable monomers soluble in water or miscible in water include those of the formula:R1 R3 \ / C = C / \ R2 R4wherein R1 and R2 are independently selected from the group consisting of H, halogen, CN, linear or branched alkyl of 1 to 10 carbon atoms (preferably 1 to 6 carbon atoms, more preferably 1 to 4 carbon atoms) ) which may be substituted, branched or linear a, β-unsaturated alkenyl or alkynyl of 2 to 10 carbon atoms (preferably 2 to 6 carbon atoms, more preferably 2 to 4 carbon atoms) which may be substituted, cycloalkyl of C3-C8 which can be substituted, NR82, N + R83, C (= Y) R5, C (= Y) NR6R7, YC (= Y) R8, YC (= Y) YR8, YS (= Y) R8, YS (= Y) 2R8, YS (= Y) 2YR8, P (R8) 2, P (= Y) (YR8) 2, P (YR8) R8, P (= Y) (YR8) R8, and aryl or heterocyclyl (as defined above) in which one or more nitrogen atoms (if present) can be quaternized with a group R8 (preferably H or C? -C alkyl); where Y can be NR8, S or O (preferably O), Rs is alkyl of 1 to 10 carbon atoms, alkoxy of 1 to 10 carbon atoms, aryl, aryloxy or heterocyclyloxy; R6 and R7 are independently H or alkyl of 1 to 20 carbon atoms, or R6 and R7 can be linked to form an alkylene group of 2 to 5 carbon atoms, thereby forming a 3 to 6 membered ring; and R8 is (independently) H, straight or branched Ci-C10 alkyl (which can be joined to form a 3- to 8-membered ring, where no more than one R8 group is covalently linked to the same atom) or aryl, and when R8 is directly linked to S or O, it can be an alkali metal or an ammonium group (N + R84); and R3 and R4 are independently selected from the group consisting of H, halogen (preferably fluorine or chlorine), CN, dC6 alkyl (preferably Ci) and COOR9 (where R9 is as defined above); or R1 and R3 can be joined to form a group of the formula (CH2) n- (which can be substituted) or C (= O) -YC (= O), where n 'is from 2 to 6 (preferably 3) or 4) and Y is as defined above; at least two of R \ R2, R3 and R4 are H or halogen; and at least one of R1, R2, R3 and R4 in at least one monomer is, or is substituted with, OH, NR82, N + R83, COOR9, C (= Y) R5, C (= Y) NR6R7, YC (= Y) R8, YC (= Y) YR8, YS (= Y) R8, YS (= Y) 2R8, YS (= Y) 2YR8, P (YR8) 2, P (= Y) (YR8) 2 , P (YR8) R8, P (= Y) (YR8) R8, P (= Y) R82, alkyl or heterocyclyl of C1-C10 substituted with hydroxy in which one or more nitrogen atoms is quaternized with a group R8 ( for example, H or C? -C alkyl). A "which can be substituted" group refers to substituted alkyl, alkenyl, alkynyl, aryl, heterocyclyl, alkylene and cycloalkyl groups according to the descriptions herein. A preferred monomer is a sulfonated acrylamide. The present invention also encompasses inflatable polymers and hydrogeyes. Hydrogels are polymers in which, in the presence of water, do not dissolve, but absorb water and thus swell in size. These polymers have found wide applications that vary from drug delivery to oil recovery. Generally, these polymeric materials are synthesized by radical polymerization of a water-soluble material in the presence of a dikyl monomer. The divinyl monomer introduces crossed chemical bonds, which makes the polymer permanently insoluble in any solvent (ie, without degrading the polymer and its physical properties). The present ATRP process also provides a process to synthesize a hydrogel, which uses physical crosslinks between chains and which allows the dissolution of the polymer without loss of physical properties. The present water-soluble polymers and hydrogel polymers can also be processed from a melt, a feature that polymers that have chemical cross-links lack. The water-soluble monomers described above can be used to prepare the water-swellable (co) polymers and hydrogels. An exemplary polymer, which was synthesized to demonstrate such capabilities is poly (N-vinylpyrrolidinone-g-styrene) (see Examples below). In a preferred embodiment, the hydrogel comprises a (co) base polymer and at least two (preferably at least three, more preferably at least and still more preferably at least five) relatively hydrophobic side chains grafted thereon (eg, by conventional radical polymerization or by the present ATRP process). The (co) base polymer can be a (co) polymer containing a water-soluble or water-miscible monomer in an amount sufficient to yield the water-soluble or water-miscible (co) polymer (e.g., containing at least 10 % mol, preferably at least 30 mol%, and preferably at least 50 mol% of the water-soluble or water-miscible monomer). Preferred hydrophobic side chains contain monomer units of the formula -R1R2C-CR3R4-, wherein: R1 and R2 are independently selected from the group consisting of H, halogen, CN, linear or branched alkyl of 1 to 10 carbon atoms ( preferably from 1 to 6 carbon atoms, more preferably from 1 to 4 carbon atoms), which may be linear or branched, substituted alkenyl or alkynyl, from 2 to 10 carbon atoms (preferably from 2 to 6 carbon atoms) carbon, more preferably from 2 to 3 carbon atoms) which can be substituted, C3-C8 cycloalkyl which can be substituted, NR82, C (= Y) R5, C (= Y) N R6R7, YC (= Y ) R8, YC (= Y) YR8, YS (= Y) R8, YS (= Y) 2R8, YS (= Y) 2YR8, P (R8) 2, P (= Y) R82, P (YR8) 2, P (= Y) (YR8) 2, P (YR8) R8, P (= Y) (YR8) R8 and aryl or heterocyclyl in which each H atom can be replaced with halogen atoms, NR8, alkyl groups of C ? -C6 or d-C6 alkoxy?; where Y can be NR8, S or O (preferably O); R5 is alkyl of 1 to 10 carbon atoms, alkoxy of 1 to 10 carbon atoms, aryl, aryloxy or heterocyclyloxy; R6 and R7 are alkyl of 1 to 20 carbon atoms, or R6 and R7 can be joined to form an alkylene group of 2 to 7 carbon atoms, thereby forming a ring of 3 to 8 members; and R8 is (independently) straight or branched C1-C10 alkyl (which can be joined to form a 3- to 7-membered ring where more than one R8 group is covalently linked to the same atoms); and R3 and R4 are independently selected from the group consisting of H, halogen (preferably fluorine or chlorine), CN, dC6 alkyl (preferably C1) and COOR9 (where R9 is alkyl of 1 to 10 carbon atoms or aril); R1 and R3 can be joined to form a group of the formula (CH2) n- (which can be substituted) where n 'is from 2 to 6 (preferably 3 or 4); and at least two of R1, R2, R3 and R4 are H or halogen. The polymers produced by the present process may be useful in general as molding materials (e.g., polystyrene containers) and as surface or barrier materials (e.g., poly (methyl methacrylate), or PMMA, it is known in this regard as PLEXIBLASMR). However, the polymers produced by the present process, which will normally have uniform, predictable, controllable and / or refined properties in relation to polymers produced by conventional radical polymerization, will be very suitable for use in performance or specialized applications. For example, polystyrene and polyacrylate block copolymers (e.g., triblock copolymers PSt-PA-Pst) are useful thermoplastic elastomers. Poly (methyl methacrylate) -polyacrylate triblock copolymers (e.g., PMMA-PA-PMMA) are useful, fully acrylic, thermoplastic elastomers. The homo- and copolymers of styrene, (meth) acrylates and / or acrylonitrile are useful adhesives, elastomers and plastics. Either random or block copolymers of styrene and a (meth) acrylate or acrylonitrile can be useful thermoplastic elastomers having high solvent resistance. Additionally, block copolymers in which the blocks alternate between the polar monomers and the non-polar monomers produced by the present invention are useful dispersants or amphiphilic surfactants to make highly uniform polymer blends. The star polymers produced by the present process are useful high impact (co) polymers. (For example, STYROLUXMR, an anionically polymerized styrene-butadiene star block copolymer, is a known high impact copolymer).
The (co) polymers of the present invention (and / or a block thereof) can have an average degree of polymerization (DP) of at least 3, preferably at least 5, and more preferably at least 10, and can have a weight average molecular weight and / or number of at least 250 g / mol, preferably at least 500 g / mol, more preferably at least 1 000 g / mol, even more preferably at least 3,000 g / mol The present (co) polymers, due to their "living" character, can have a maximum molecular weight without limit. However, from a practical perspective, the present (co) polymers and blocks thereof may have a weight average molecular weight or number greater than, for example, 5,000,000 g / mol, preferably 1,000,000 g / mol, more preferably 500,000 g / mol, and even more preferably 250,000 g / mol. For example, when it is produced in bulk, the number average molecular weight can be up to 1,000,000 (with a weight average molecular weight or minimum number as mentioned above). The number average molecular weight can be determined by size exclusion chromatography (SEC) or, when the initiator has a group which can be easily distinguished from the monomer (s), by NMR spectroscopy (e.g., when 1-phenylethyl chloride is the initiator and methyl acrylate is the monomer). Thus, the present invention also encompasses novel terminal, telechelic and hyperbranched functional homopolymers, and block, multi-block, star, gradient, random, graft or "comb" and hyperbranched copolymers. Each of these different types of copolymers will be described hereinafter. Because ATRP is a "living" polymerization, it can be started and stopped, practically at will. Additionally, the polymer product retains the "X" functional group necessary to initiate further polymerization. Thus, in one embodiment, once the first monomer is consumed in the initial polymerization step, a second monomer can then be added to form a second block in the growing polymer chain in a second polymerization step. Additional polymerizations with the same or different monomers can be made to prepare multi-block copolymers. Additionally, since ATRP is radical polymerization, the blocks can be prepared essentially in any order. One is not necessarily limited to preparing block copolymers where the sequential polymerization steps must flow from the less stabilized polymer intermediate to the more stabilized polymer intermediate, so that ionic polymerization is necessary. In this way, one can prepare a multi-block copolymer in which a polyacrylonitrile or a block of poly (meth) acrylate is prepared first, then a block of styrene or butadiene is attached thereto, etc. As described through the application, certain advantageous reaction design choices will become apparent. However, one is not limited to these advantageous reaction design choices in the present invention.
In addition, a linking group is not necessary to join the different blocks of the present block copolymer. One can simply add successive monomers to form successive blocks. Additionally, it is also possible (in some cases advantageous) to first isolate a (co) polymer produced by the present ATRP process, then to react the polymer with an additional monomer using a different initiator / catalyst system (to "equalize" the reactivity of the polymer chain growing with the new monomer). In such a case, the product polymer acts as the new initiator for the further polymerization of the additional monomer. In this manner, the present invention also encompasses terminal functional homopolymers having a formula:and random copolymers having a formula:A - [(M1) ¡(M2) j] -X A - [(M1) i (M) j (M3) k] -X or A - [(M1) i (M) j (M3) k .. . (Mu),] - Xwhere A can be R11 R12R13C, R11R12R13Si, (R1 1) mSi, R11 R1 N, (R1 1) nP,(R 1 1 O) n P, (R 1 1) (R 12 O) P, (R 11) pP (O), (R 1 1 O) n P (O) or (R 1 1) (R 12 O) P (O); R1 1,R12, R13 and X are as defined above; M1, M2, M3, ... to Mu are each a polymerizable monomer by rad (as defined above); h, i, j, k ... to I are each an average degree of polymerization of at least 3; and i, j, k ... to I represent molar proportions of the polymerizable monomers by means of rad M1, M2, M3, ... up to Mu.
Preferably, at least one of M1, M2, M3, ... up to Mu has the formula:R1 R3 \ / C = C / \ R2 R4wherein at least one of R1 and R2 is CN, CF3, linear or branched alkyl from 4 to 20 carbon atoms (preferably from 4 to 10 carbon atoms, more preferably from 4 to 8 carbon atoms), cycloalkyl C3-C8, aryl, heterocyclyl, C (= Y) R5, C (= Y) NR6R7 and YC (= Y) R8, wherein aryl, heterocyclyl, Y, R5, R6, R7 and R8 are as defined above; and R3 and R4 are as defined above; or R1 and R3 are joined to form a group of the formula (CH2) n, or C (= O) - Y-C (= O), where n 'and Y are as defined above. Preferably, these (co) polymers have either a weight average molecular weight or number of at least 250 g / ml, more preferably at least 500 g / mol, even more preferably 1, 000 g / mol and most preferably at least 3,000 g / mol. Preferably, the (co) polymers have a polydispersity of 1.50 or less, more preferably 1.35 or less, still more preferably 1.25 or less and most preferably 1.20 or less. Although the present gels may have a weight average molecular weight or number reasonably above 5,000,000 g / mol, from a pract perspective, the present (co) polymers and blocks thereof may have a weight average molecular weight or higher number of , for example, 5,000,000 g / mol, preferably 1,000,000 g / mol, more preferably 500,000 g / mol, and even more preferably 250,000 g / mol. Preferred random copolymers include those prepared from any combination of styrene, vinyl acetate, acrylonitrile, acrylamide and / or d-C8 alkyl (meth) acrylates, and particularly include those of (a) methyl methacrylate and styrene having from 10 to 75 mol% of styrene, (b) methyl methacrylate and methyl acrylate having from 1 to 75% mol of methyl acrylate, (c) styrene and methyl acrylate, and (d) methyl methacrylate and butyl acrylate. The present invention also concerns block copolymers of the formula:A- (M1) p- (M2) qX A- (M1) p- (M2) q- (M3) rX A- (M1) p- (M2) q- (M3) r -...- (Mu ) s -Xwhere A and X are as defined above; M1, M2, M3, ... up to Mu are each a monomer polymerizable by rad (as defined above) selected so that the monomers in the adjacent blocks are not ident (although the monomers in the non-adjacent blocks may be to be ident) and p, q, r, ... to s are independently selected so that the average degree of polymerization and / or the average molecular weight of weight or number of each block or copolymer as a whole can be described above for those present (co) polymers. After an appropriate terminal group conversion reaction (conducted according to known methods), X can also be, for example, H, OH, N3, NH2, COOH or CONH2. Preferred block copolymers can have the formulaR11R12R13C- (M1) p- (M2) qXR11R12R13C- (M1) p- (M2) q- (M3) r -X or R11R12R13C- (M1) p- (M2) q- (M3) r -... - (Mu) s -XPreferably, each block of the present block copolymers has a polydispersity of 1.50 or less, more preferably 1.35 or less, still more preferably 1.25 or less and more preferably 1.20 or less. The present block copolymer, as a complete unit, can have a polydispersity of 3.0 or less, more preferably 2.5 or less, still more preferably 2.0 or less and most preferably 1.50 or less. The present invention can be used to prepare periodic or alternating copolymers. The present ATRP process is particularly useful for producing alternating copolymers where one of the monomers has one or two bulky substituents (eg, where at least one of M1, M2, M3, ... to Mu are each 1, 1 - diaryi ethylene, C1-C20 diesters of didehydromalonate, diesters of fumaric or maleic acid, maleic anhydride and / or maleic diimides [where Y is NR8 as defined above], etc.), from which homopolymers can be difficult to prepare , due to steric considerations. Thus, some combinations of preferred monomers for the present alternating copolymers containing "bulky" substituents include combinations of styrene, acrylonitrile and / or C-C8 esters of (meth) acrylic acid, with maleic anhydride, C-alkyl maleimides. -C8 and / or 1, 1 -difenylethylene. The copolymerization of monomers with donor and receptor properties results in the formation of products with predominantly alternating monomer structure (Cowie, "Alternanting Copolymerization," Comprehensive Polymer Science, vol.4, p.377, Pergamon Press (1989)). These copolymers can exhibit interesting physical and mechanical properties that can be attributed to their alternating structure (Cowie, Alternating copolymers, Plenum, New York (1985)). The so-called "alternating" copolymers can be produced using the present method. The "alternating" copolymers are prepared by copolymerization of one or more monomers having electron donor properties (e.g., unsaturated hydrocarbons, vinyl ethers, etc.) with one or more monomers having electron receptor-like properties (acrylates, methacrylates) , unsaturated nitriles, unsaturated ketones, etc.). Thus, the present invention also concerns an alternating copolymer of the formula:A-ÍWr-Wr X A- (M1-M2) p- (M2-M1) qX A- (M1-M2) p- (M2-M1) q- (M1-M2) rX or A- (M1-M) ) p- (M2-M1) q- (M1-M2) r -...- (Mv-My) s -Xwhere A and X are as defined above, M1 and M2 are different polymerizable monomers by radical (as defined above), and Mv is one of M1 and M2 and My is the other of M1 and M2. However, p, q, r, ... even s are independently selected so that the average degree of polymerization and / or the weight average molecular weight or number of the copolymer as a whole or of each block can be described above by the (co) terminal or random functional polymers. (The description "r ... to s" indicates that any number of blocks equilvalent to those designated by the subscripts p, q, and r may exist between the blocks designated by the subscripts r and s.) Preferably, A is R11 R12R13C, M1 is one or more monomers having electron donor properties (eg, unsaturated C2-C20 hydrocarbons which may have one or more alkyl, alkenyl, alkynyl, alkoxy, alkylthio, dialkylamino, aryloyl or tri (alkyl and / or aryl) silyl as defined above [eg, isobulene or vinyl C2-C10 ethers, etc.) and M2 is one or more monomers having electron receptor properties (eg, (meth) acid) acrylic or a salt thereof, esters of C? -C20 (meth) acrylate, unsaturated C3-C2o nitriles, C3-C20? -unsaturated aldehydes, ketones, sulfones, phosphates, sulfonates, etc., as defined before).
Preferably, the present alternating copolymers have either a weight average molecular weight or number of at least 250 g / mol, more preferably 500 g / mol, still more preferably 1 000 g / mol, and most preferably 3,000 g / mol. mol. Preferably, the present alternating copolymers have a weight average molecular weight or maximum number of 5,000,000 g / mol, preferably 1,000,000 g / mol and even more preferably 500,000 g / mol, although the upper limit of the molecular weight of those present (co) "living" polymers is not limited. Preferably, the present alternating copolymers have a polydispersity of 1.50 or less, more preferably 1.35 or less, still more preferably 1.25 or less and most preferably 1.20 or less. The present random or alternating copolymer can also serve as a block in any of the block, star, graft, comb or hyperbranched copolymers. Where group A (or preferably R11 R12R13C) of the initiator contains a second "X" group, ATRP can be used to prepare "telechelic" (co) polymers. The "telechelic" homopolymers can have the following formula:where A (preferably R11 R12R13C) and X are as defined above, M is a monomer polymerizable by radical as defined above, and p is an average degree of polymerization of at least 3, subject to the condition that A is a group that supports a substituent X.
Preferred telechelic homopolymers include those of styrene, acrylonitrile, C?-C8 esters of (meth) acrylic acid, vinyl chloride, vinyl acetate and tetrafluoroethylene. Such telechelic homopolymers preferably have either a weight average molecular weight or number of at least 250 g / mol, more preferably at least 500 g / mol, even more preferably at least 1 000 g / mol, and very preferably at least 3,000 g / mol, and / or have a polydispersity of 1.50 or less, more preferably 1.3 or less, even more preferably 1.2 or less and most preferably 1.15 or less. From a practical point of view, the present alternating copolymers can have a weight average molecular weight or maximum number of 5,000,000 g / mol, preferably 1,000,000 g / mol, more preferably 500,000 g / mol, and even more preferably 250,000 g. / mol, although the upper limit of the molecular weight of the "living" (co) polymers is not particularly limited. Block copolymers prepared by ATRP from an initiator having a second "X" group may have one of the following formulas:X- (M2) q- (M1) p- (A) - (M1) p- (M2) qX X- (M3) r- (M2) q- (M1) p- (A) - (M1) p - (M2) q- (M3) rX X- (Mu) s -...- (M3) r- (M2) q- (M1) p- (A) - (M1) p- (M) q- (M3) r -...- (Mu) sXand the random copolymers can have one of the following formulas:X - [(M1) p- (M2) q] - (A) - [(M1) p- (M2) q] -X X - [(M1) p- (M2) q- (M3) r] - (A) - [(M1) p- (M2), - (M3) r] -X X - [(M1) p- (M2) q- (M3) r -...- (Mu) s] - (A) - [(M1) p- (M2) q- (M3) r -...- (Mu) s] -Xwhere A (preferably R11R1 R13C), X, M1, M2, M3, ... to Mu, and p, q, r, ... to s are as defined above, subject to the condition that A is a group that supports a substituent X. The present invention also concerns gradient copolymers. The gradient copolymers form a completely new class of polymers with a controlled structure and composition which changes gradually and in a systematic and predictable manner along with the copolymer chain (Scheme 2). Due to this compositional distribution and consequent unusual interchain interactions, it is expected that the gradient copolymers have very unique thermal properties (e.g., glass transition temperatures and / or melting points). They can also exhibit unprecedented phase separation and unusual mechanical behavior, and can provide unique capabilities as surfactants or as modifiers for incompatible mixing materials. The gradient copolymers can be obtained in a system without an important chain breaking reaction, such as ATRP. To control the composition of the copolymer, it is beneficial to maintain continuous growth of the polymer chain and regulate the comonomer feed composition during the course of the reaction. Otherwise, the distribution of the monomer units along the polymer chain can be random or block-like. To date, there are no publications on the subject of gradient copolymers. The closest examples described so far are tapered copolymers prepared through living anionic polymerization (Sardelis et al., Polymer, 25, 101 1 (1984) and Polymer, 28, 244 (1987); Tsukuhara et al., Polym. 12, 455 (1980)). The tapered copolymers differ from the gradient copolymers in that they retain the block-like character despite the composition gradient in the middle block. Additionally, the composition gradient of the tapered polymers is inherent and can not be changed or controlled.
Scheme 2 AAAAABAAAABAAABAABABBABBBABBBBABBBBBChain length O Monomer A Monomer B Gradient copolymers can be prepared via ATRP copolymerization of two or more monomers with different proportions of homopolymerization reactivity (eg, r1> g2, where r1 can be greater than 1 and r2 it can be less than 1). Such comonomers usually do not randomly copolymerize (Odian, Principles of Polymerization, 3rd ed., John Wiley &Sons, New York, pp. 463 (1991)). For example, in the conventional radical polymerization, a mixture of homopolymers is obtained. In the present controlled system, where the polymer chain is not terminated at any stage of the reaction, initially only the most (or most) reactive monomer reacts until its concentration decreases to such a level that the monomer less (or the second more ) Reagent begins to be incorporated into the growing polymer chains. The less reactive monomer is gradually incorporated into the polymer chain to a greater degree, and its content in the chain increases, as more reactive monomer is consumed more. Finally only the less reactive monomer is present in the system and as it reacts, it forms a block of the less reactive monomer at the end of the chain. The composition gradient in such a copolymer is controlled by the difference in the reactivity ratios and the proportion with which each of the monomers reacts. It can also be considered as an inherent control over the composition of the copolymer, which can be altered by intentionally changing the concentration of one or more of the monomers.Thus, in one example of the gradient copolymerization including two different monomers, the polymerization step of the present atom transfer or group polymerization method may comprise polymerizing the first and second polymerizable monomers by radical present in amounts that provide a molar ratio of the first monomer to the second monomer of a: bab: a, where a and b are each from 0 to 100 and (a + b) = 100, then adding an additional amount of the first and / or second monomer that provides a molar of the first monomer to the second monomer of c: nity: c, where c differs from a, d differs from by (c + d) = 100, and if desired, repeating as often as desired the addition step so that yes c > a, the molar ratio (or percentage) of the first monomer increases, but if d > b, the molar ratio (or percentage) of the second monomer increases. The addition step (s) can be continuous, in intermittent portions or all at once. In this way, the present invention also encompasses a gradient copolymer of the formula:A-M1 n- (M1 aM2b)? -...- (M10M2d) y-M2m-Xwhere A and X are as defined above, M1 and M2 are polymerizable monomers by radical (as defined above) having different reactivities (preferably in which the ratio of homopolymerization and / or copolymerization reactivity rates are less than 1.5, more preferably at least 2 and most preferably at least 3), a, b, c and d are non-negative numbers independently selected so that a + b = c + d = 100, where the ratio a: b is from 99: 1 to 50:50, the ratio c: d is from 50:50 to 99: 1, and the molar ratio of M1 to M2 gradually decreases along the length of the polymer chain of a: bac: d, yn, m, xyy are independently an integer of at least 2, preferably at least 3, more preferably at least 5 and most preferably at least 10. The average molecular weight of weight or number of each block or copolymer as a whole can be as described above for ra present (co) polymers. Preferably, A is R11 R R13C, and X is a halogen. To determine the gradient, the copolymerization can be sampled intermittently, and the molar ratio of copolymer units corresponding to each monomer is determined according to known methods. Whenever the proportion of a monomer increases as one or the other decreases during the course of the copolymerization, the molar ratio of that monomer increases along the length of the polymer chain as one or the other decreases. Alternatively, the decrease in monomer ratio along the length of the polymer chain a: b to c: d can be determined according to the numbers of monomer units along the polymer chain. The number of sub-blocks must be less than the number of monomer units in each sub-block, but the sub-blocks may overlap by a number of monomer units smaller than the size of the sub-block. For example, where the central block of the polymer contains 6 monomer units, the proportions can be determined by two sub-blocks of 3 units (eg, (3-mer) - (3-mer)). Where the central block of the polymer contains, for example, 9 monomer units, the proportions can be determined by three sub-blocks of 4 units, where the central sub-block overlaps each terminal sub-block with a monomer unit (e.g. -mer) - (4-mer overlap) - (4-mer) Where the central block of the polymer contains, for example, 10 to 50 monomer units, the proportions can be determined by sub-blocks of 5 to 10 units ( for example, (5-mer) - (5-mer), (6-mer) - (8-mer) - (6-mer), (10-mer) - (10-mer), (mer-mer) - (5-mer) - (5-mer) - (5-mer), etc.) Where the central block of the polymer contains, for example, from 51 to 380 monomer units, the proportions can be determined by sub-blocks from 10 to 20 units; etc. Such copolymers can be prepared by carefully controlling the molar ratios of monomers for each other and for latent polymer chains or initiator. In another embodiment, the relative proportions of the first monomer to the second monomer are controlled in a continuous manner, using for example by adding the second monomer via a supply delivery pump or programmable syringe. When either the initiator or the monomer contains a substituent that supports a portion of acetylene or remote ethylene (ie, unconjugated), ATRP can be used to prepare crosslinked polymers and copolymers.
The present invention is also useful for forming so-called "star" polymers and copolymers. In this way, where the initiator has three or more "X" groups, each of the "X" groups can serve as a polymerization initiation site. Thus, the present invention also encompasses (co) star polymers of the formula:A '- [(M1) PX] Z A' - [(M1) p- (M2) qX] z A '- [(M1) p- (M2) q- (M3) rX] z A * - [( M1) p- (M2) q- (M3) r -...- (Mu) sX] z A '- [(M1 iM2j) -X] z A' - [(M1¡M2jM3k ... Mu,) -X] zwhere A 'is the same as A with the proviso that R11, R12 and R13 combined contain 2 to 2 groups X, where X is as defined above; M1, M2, M3, ... MU are as defined above for the present block copolymers; and z is from 3 to 6. Preferably, A 'is R11 R12R13C, and X is halogen (preferably chlorine or bromine). Suitable initiators for use in the preparation of the present star (co) polymers are those in which the group A (or preferably R 1 R 12 R 13 C) has at least three substituents, which may be "X" (as defined before). Preferably, these substituents are identical to "X". Examples of such initiators include compounds of the formula C6Hx (CH2X) and or CHX (CH2X) y-, where X is a halogen, x + y = 6, x '+ y' = 4 and y and y 'are each > 3. Preferred initiators of this type include 2,2-bis (chloromethyl) -1,3-dicyopropane, 2,2, -bis (bromomethyl) -1,3-dibromopropane), a, a ', a " -trichloro-a, a ', a -tribromocumene, and tetrakis- and hexakis (a-chloro- and a-bromomethyl) benzene), with hexakis (a-bromomethyl) benzene being the most preferred. The branched and hyperbranched polymers can also be prepared according to the present invention. The synthesis of hyperbranched polymers has been explored to develop dendritic molecules in a simple reaction, from a pot. Conventional hyperbranched polymers are obtained by the reaction of monomers AB2 in which A and B are portions containing functional groups capable of reacting with each other to form stable bonds. Due to the structure AB2 of the monomers, the reaction of two monomers results in the formation of a dimer with a group A and three groups B. This process repeats itself by reaction with either monomer, dimer, trimer, etc. , in a similar way to provide gradual polymer growth. The resulting polymer chains have only one group a and (n + 1) groups B, where n is the number of repeating units. The polymers resulting from these reactions are sometimes highly functionalized. However, these polymers do not have perfectly symmetrical architectures, but instead have irregular shapes. This may be due to uneven growth of the macromolecule in several directions.
The present hyperbranched polymers have some of the qualities of the dendrimers, but lack some properties of perfect dendrimers. The cationic process described by Frechet et al. (Science 269, 1080 (1995)) differs from the present synthesis of hyperbranched polymers not only in the polymerization mechanism, but also in extending the reaction to primary benzyl halides. The present invention also concerns a process for preparing hyperbranched polymers (e.g., hyperbranched polystyrene) by atom or group transfer radical polymerization (ATRP), preferably in "a pot" (e.g., in a simple reaction sequence without steps of substantial purification, and more specifically, in a simple reaction vessel without any intermediate purification step), using the present process and at least one monomer polymerizable by radical, in which at least one of R, R2 , R3 and R4 also contains a radical-transferable X group, optionally in the absence of an initiator (or if an initiator is used, the X group of the monomer may be the same or different from the X group of the initiator). For example, commercially available p-chloromethylstyrene (p-CMS) can be polymerized in the presence of a transition metal compound (e.g., Cu (l) and ligand (e.g., 2,2'-bipyridyl, or "bipy"). ") A demonstrative example of the copolymerization of styrene and p-CMS, and its comparison with a linear standard, is presented in the Examples below.
In fact, the monomer can also act as an initiator (for example, the homopolymerization of p-CMS in the presence of Cu (1) and bipy). It is possible to remove the chlorine atom in the benzilic position homolytically, thereby forming Cu (II) CI2 and a benzyl radical capable of initiating the polymerization of monomer through the double bonds (see Scheme 3). This results in the formation of a polymer chain with pendant groups consisting of p-benzyl chloride. Also, the polymer has a double ligation at the end of the chain, which can be incorporated into the growing polymer chain. Thus, the present invention also concerns a hyperbranched (co) polymer of the formula:M1- (M1 aM2 bM3c ... Mud) -Xe and / or M1- (M1 aM2bM3c ... Mud) - [(M1) p- (M2) q- (M3) r -...- (Mu) f] -Xgwhere M1 is a monomer polymerizable by radical having both a carbon-carbon multiple bond and at least one X group (as defined above); M2, M3 ... to Mu are polymerizable monomers by radical (as defined above); a, b, c ... up to d are numbers of at least zero, so that the sum of a, b, c. to d is at least 2, preferably at least 3, more preferably at least 4 and most preferably at least 5; e is the sum of the products of (i) a and the number of groups X in M1, (¡i) b and the number of group X in M2, (iri) c and the number of groups X in M3 ... up to (iv) ) d and the number of X groups in Mu; f = e y (g + h + i + j + k) = e. The formula "M1- (M1aM2bM3c ... Mud) -Xe" represents a "perfect" hyperbranched polymer, in which each "X" group is at the end of a chain or branch of monomer units. (In the hyperbranched (co) polymer present, a "chain" can be defined as the longest continuous series of monomer units of a polymer.A "branch" can be defined as any series covalently linked to monomer units in the polymer containing a number. of monomer units smaller than the "chain".) The formula:M1- (M1 aM2bM3c ... Mud) - [(M1) p- (M2) q- (M3) r -...- (Mu) f] -Xgrepresents those (co) polymers in which one or more "X" groups are linked to non-terminal monomer units (i.e., monomer units not at the end of a branch or chain). In fact, the present invention also encompasses those (co) polymers in which the "X" substituent is located at either or both ends of the (co) polymer chain, in an internal monomer unit, or any combination thereof. "Internal" X groups can be placed in place by incorporating a monomer into the polymer chain having a substituent encompassed by the definition of "X" above. In the hyperbranched (co) polymer present, the number of branches will be at most 2 (a "1) -1, assuming that all the" X "groups are active in the subsequent ATRP steps, where, for example, a number" h " "or of groups" X "fails to react in the subsequent ATRP steps (eg, where one of the 1st or 2nd group Cl in a branch in the octamer shown in Scheme 3 below does not react in subsequent steps, but the other yes), a product of the formula:M1- () - [(M1) p- (M2) q- (M3) r -...- (Mu) f] -Xgit is formed. The subsequent number of branches is reduced by 2h.
The present invention also concerns crosslinked polymers and gels, and processes for producing them. By conducting the polymerization step, which produces the present branched and / or hyperbranched (co) polymers for a longer period of time, the gelled polymers can be formed. For example, by increasing the amount or proportion of styrene of p-chloromethyl in the reaction mixture (for example, in relation to a solvent or other monomer (s)), the crosslink density may be increased and the time of reaction can be decreased.(activation)Activation Monomer(Typically, a polymerization step in any aspect of the present invention can be conducted for a sufficient period of time to consume at least 25%, preferably at least 50%, more preferably at least 75%, still more preferably at least 80% and most preferably at least 90% monomer. Alternatively, the present polymerization step can be conducted for a period of time sufficient to render the reaction mixture too viscous to stir, mix or pump with the stirring, mixing or pumping means being used. However, the polymerization step can generally be conducted for any desired period of time). The present invention also encompasses graft copolymers or "comb", prepared by sequential polymerizations. For example, a first (co) polymer can be prepared by conventional radical polymerization, then a second (co) polymer chain or block (or one or more) can be grafted onto the first (co) polymer by ATRP; a first (co) polymer can be prepared by ATRP, then one or more (co) polymer chains or blocks. they can be grafted onto the first (co) polymer by conventional radical polymerization; or the first (co) polymer can be prepared and the additional chains or blocks of (co) polymer can be grafted onto it by sequential ATRPs. A combination of ATRP and one or more other polymerization methods can also be used to prepare different blocks of a linear or star block copolymer (i.e., when extending one or more chains from a base (co) polymer). Alternatively, a combination of ATRP and one or more different polymerization methods can be used to prepare a "block homopolymer", in which blocks other than a homopolymer having one or more different properties (eg, tacticity) are prepared by different polymerization processes. Such "block homopolymers" may exhibit microfase separation. Thus, the present invention further concerns a method of preparing a graft (co) polymer or "comb", which includes the present ATRP process, which may comprise reacting a first (co) polymer having either a substituent X transferable by radical (as defined above) or a group that is easily converted (by known chemical methods) into a transferable substituent by radical with a mixture of (i) transition metal compound capable of participating in a reversible redox cycle with the first (co) polymer, (ii) a ligand (as defined above) and (iii) one or more polymerizable monomers by radical (as defined above) to form a reaction mixture containing the ( co) graft polymer or "comb", then isolating the graft (co) polymer or "comb" formed from the reaction mixture. The method may further comprise the step of preparing the first (co) polymer by radical, anionic, cationic or exchange polymerization or by a first ATRP, in which at least one of the monomers has a substituent R1-R4, the which is covered by the description of the group "X" above. Where the catalyst and / or initiator used to prepare the first (co) polymer (for example, a Lewis acid used in conventional cationic polymerization, a conventional exchange catalyst having a multiple metal-carbon ligation, a conventional organolithium reagent) can being incompatible with the chosen ATRP initiator / catalyst system, or it may produce an incompatible intermediate, the process may further comprise the step of deactivating or removing the catalyst and / or initiator used to prepare the first (co) polymer prior to the step of grafting (i.e., reacting the first (co) polymer with the subsequent monomer (s) by means of ATRP). Alternatively, the method for preparing a graft (co) polymer or "comb" may comprise preparing a first (co) polymer by the present ATRP process, then grafting a number of (co) polymer chains or blocks into the first (co) polymer by forming the same number of covalent bonds between the first (co) polymer and one or more polymerizable monomers (e.g., by conventional radical polymerization, conventional anionic polymerization, conventional cationic polymerization, conventional exchange polymerization, or the present ATRP process), polymerize the polymerizable monomer (s) according to the aforementioned conventional process or ATRP to form a reaction mixture containing the graft (co) polymer or "comb", then isolating the (co) graft polymer or comb "of the reaction mixture. Preferably, the substituent X in the first (co) polymer is Cl or Br. Examples of preferred monomers for the first (co) polymer include, in this manner, allyl bromide, allyl chloride, vinyl chloride, 1- or 2- chloropropene, vinyl bromide, 1, 1- or 1, 2- dicioro-Q dibromoethane, troro- or tribromethylene, tetrachloro- or tetrabromoethylene, chloroprene, 1-chlorobutadiene, 1- or 2-bromo butadiene, vinyl chloroacetate, vinyl doroacetate , vinyl troroacetate, etc. The most preferred monomers include vinyl chloride, vinyl bromide, vinyl chloroacetate and chloroprene. It may be necessary or desirable to hydrogenate (by known methods) the first (co) polymer (e.g., containing chloroprene units) before grafting by ATRP. Thus, the present invention also encompasses (co) graft polymers or "comb" having a formula:Xf.ßR "- (M 1i-X) e Xf.eR" - [(M1 iM2j) -X] e Xf_eR "- [(M1 iM2jM3k) -X] e Xf_eR" - [(M1¡M2jM3k ... Mu ,) - X] e Xf.eR "- [(M1) p- (M2) qX] e Xf_eR" - [(M1) p- (M2) q- (M3) rX] e Xf.eR "- [( M1) p- (M2) q- (M3) r -...- (Mu) sX] ewhere R "is a first (co) polymer residue of a first copolymer having a formula RXf, f> e is a number having an average of at least 2.5, preferably at least 3.0, more preferably at least 5.0, and most preferably at least 8.0, X is as defined above (and is preferably a halogen), M1, M2, M3, ... to Mu are each a monomer polymerizable by radical (as defined above); p, q, rys are selected to give weight average molecular weight or number for the corresponding block is at least 100 g / mol, preferably at least 250 g / mol, more preferably at least 500 g / mol and even more preferably at least 1 000 g / mol, ei, j, k ... to I represent molar proportions of the polymerizable monomers by means of radical M1, M2, M3, ... to Mu. Polydispersity, average degree of polymerization and / or weight average molecular weight or (co) polymer number or component thereof (for example, base polymer or graft side chain) can be as described above. Preferred graft copolymers include those in which the first (co) polymer includes at least three units of vinyl chloride, vinyl bromide, or a halo-C-C20-C2-C3-alkenyl alkanoate ester ( for example, vinyl chloroacetate). Most preferred graft copolymers include those in which the first (co) polymer is a copolymer of N-vinylpyrrolidone / vinyl chloroacetate containing on average at least three units of vinyl chloroacetate per chain, in which the polystyrene chains are grafted onto them by ATRP using the chloroacetate moiety as initiator. It is expected that such graft copolymers will be useful for making, for example, disposable contact lenses. In the present copolymers, each of the blocks can have a number average molecular weight according to the homopolymers described above. Thus, the present copolymers can have a molecular weight which corresponds to the number of blocks (or in the case of star polymers, the number of branches determines the number of blocks) determines the number average molecular weight range for each block. The polymers and copolymers produced by the present process have surprisingly decreased the polydispersities for the (co) polymers produced by radical polymerization. Typically, the ratio of the weight average molecular weight to the number average molecular weight ("Mw / Mn") is < 1.5., Preferably < 1 .4, and can be as low as 1 .10 or less. Because the "living" (co) polymer chains retain an initiator fragment in addition to X or X 'as a terminal group or as a substituent in the polymer chain, they can be considered (co) (multi) functional in-chain polymers or functional terminals. Such (co) polymers can be used directly or can be converted to other functional groups for further reactions, including crosslinking, chain extension, reactive injection molding (RIM), and preparation of other types of polymers (such as polyurethanes, polyimides, etc.) .). The present invention provides the following advantages: • A larger number and a wider variety of mopomers can be polymerized by radical polymerization, in relation to ionic and other chain polymerizations; • Polymers and copolymers produced by the present process exhibit low polydispersity (eg, Mw / Mn < 1.5, preferably < 1.4, more preferably < 1 .25, and most preferably < 1 .10 ), thus ensuring a greater degree of uniformity, control and predictability in the properties of (co) polymers; • One can select an initiator which provides a terminal group that has the same structure as the repetitive polymer units (1-phenylethyl chloride as initiator and styrene as monomer); • The present process provides high monomer conversion and high initiator efficiency; • The present process exhibits excellent "living" character, thus facilitating the preparation of block copolymers, which can not be formed by ionic processes; • Polymers produced by the present process are well defined and highly uniform, comparable with polymers produced by living ionic polymerization; • Terminal functional initiators (for example, containing groups COOH, OH, NO2, N3, SCN, etc.) can be used to provide a terminal functional polymer in a pot, and / or polymer products with different functionalities at each end (by example, in addition to one of the above groups at one end, a carbon-carbon double bond, epoxy group, imino, amide, etc., at another extreme);• The terminal functionality of the (co) polymers produced by the present process (for example, Cl, Br, I, Cn, CO2R) can easily be converted to different functional groups (for example, Cl, Br, I can be converted to OH or NH2 by known processes, CN or CO2R can be hydrolyzed to form carboxylic acid by known processes, and a carboxylic acid can be converted by known processes to a carboxylic acid halide), thereby facilitating its use in chain extension processes (for example, example, to form long-chain polyamides, polyurethanes and / or polyesters);• In some cases (for example, where "X" is Cl, Br and I), the terminal functionality of the polymers produced by the present process can be reduced by known methods to provide end groups having the same structure as the repeating polymer units. . • Even greater improvements can be made by using (a) a corresponding amount of reduced or oxidized transition metal compound, which deactivates at least part of the free radicals, which can adversely affect polydispersity and molecular weight / capacity control of prediction and / or (b) polymerizing in a homogeneous system or in the presence of a solubilized initiation / catalytic system; • A wide variety of (co) polymers that have various structures and topologies (for example, hydrogels and block copolymers, random, graft, alternating, tapered (or "gradient"), star,"hyperbranched", cross-linked and water soluble), which may have certain desired properties or a certain desired structure can be easily synthesized; and • Certain such (co) polymers can be prepared using water as a medium.
Other features of the present invention will become apparent in the course of the following descriptions of the exemplary embodiments, which are given for illustration of the invention, and are not intended to be limiting thereof.
EXAMPLESExample 1: The effect of exposure to air on heterogeneous styrene ATRP. The following quantities of reagents were weighed into each of the three glass tubes under an inert atmosphere in a dry box filled with nitrogen: 1.0 mg (4.31 x 10"2 mmol) of [(bipy) CuCl] 2 (Kitagawa, S .: Munakata, M. Inorg, Chem. 1981, 20, 2261), 1.00 ml (0.909 g, 8.73 mmol) of uninhibited, dry styrene, and 6.0 μl (6.36 mg, 4.52 x 10"2 mmol) of 1-phenylethylchloride [1 -PECI]. The first tube was sealed under vacuum without exposure to air. The second tube was uncapped out of the dry and shaken box while exposed to the ambient atmosphere for two minutes. The tube was then attached to a vacuum line, the contents were frozen using liquid nitrogen, the tube was placed under vacuum for five minutes, the contents were thawed, and then argon was introduced into the tube. This "freeze-pump-thaw" procedure was repeated before the tube was sealed under vacuum, and it was ensured that the dioxygen was removed from the polymerization solution. The third tube was exposed to ambient atmosphere for 10 minutes and subsequently sealed using the same procedure. The three tubes were heated at 130 ° C for 12 h using an oil bath with thermostat. Subsequently, the individual tubes were broken, and the contents were dissolved in tetrahydrofuran [THF] and precipitated in CH3OH. The volatile materials were removed from the polymer samples under vacuum. Molecular weights and polydispersities were measured using gel permeation chromatography [GPC] in relation to polystyrene standards. The results are shown in Table 1 below.
Table 1: Results of the air exposure experimentsExample 2: General procedure for homogeneous styrene ATRP. The following amounts of reagents were weighed into glass tubes under ambient atmosphere: 12.0 mg (8.37 x 10"2 mmol) of CuBr1 0.00 ml (0.909 g, 8.73 mmol) of uninhibited styrene, and 12.0 .mu.l (16.3 mg, 8.8 x 10"2 mmol) of 1 -feniletilbromuro [1 -PEBr]. For polymerizations using dNbipy, 72.0 mg (0.175 mmol ) of ligand were added, for dTbipy, 47.0 mg (0.175 mmol) were added, and for dHbipy, 62.0 mg (0.175 mmol) were added.Two "freeze-pump-thaw" cycles (described above) were performed on the contents of each tube in order to ensure that the dioxygen was removed from the polymerization solution.Each tube was sealed under vacuum.The tubes were placed in an oil bath with thermostat at 100 ° C. At intervals of time, the tubes were removed of the oil bath and cooled to 0 ° C using an ice bath in order to extinguish the polymerization.Subsequently, the individual tubes were broken and the contents dissolved in 10.0 ml of TH F. The catalyst could be removed by passing the polymer solution through an alumina column The percentage of conversion of each sample was measured using gas chromatography, and the molecular weights and polydispersities were measured using GPC in relation to polystyrene standards. The results are shown in Tables 2 and 3 below.
Table 2: Molecular weight data for the homogeneous styrene ATRP using dTbipy as the ligand.
Table 3: Molecular weight data for the homogeneous styrene ATRP using dHbipy as the ligand.
Example 3: General procedures for the determination of the effect of copper (ll) added in homogenous styrene ATRP. dHbipy was prepared according to the procedure of Kramer et al (Angew. Chem., Intl. Ed. Engl. 1993, 32, 703). dTbipy was prepared according to the procedure of Hadda and Bozec (Polyhedron 1988, 7, 575). CuCl was purified according to the procedure of Keller and Wycoff (Inorg, Synth, 1946, 2, 1).
Method 1: Heavy addition of the transition metal reagents In a dry box, appropriate amounts of pure CuCl, pure CuCI2, bipyridyl ligand, dry 1-PE and 1,4-dimethoxybenzene were added to a 100 ml Sclenk flask equipped with a magnetic stirrer bar. The flask was fitted with a rubber septum, removed from the dry box and attached to the Schlenk line. The appropriate amounts of uninhibited styrene, dry and high boiling solvent were added to the flask, and the septum was fixed in place using copper wire. The flask, with the polymerization solution always under an argon atmosphere, was heated to 130 ° C using an oil bath with thermostat, and upon heating a homogeneous reddish brown solution was formed. Aliquots of the polymerization solution (2.00ml) were removed at time intervals using a purged syringe and dissolved in 10.0 ml of THF. The percent conversion of each sample was measured using gas chromatography, and the molecular weights and polydispersities were measured using GPC in relation to polystyrene standards.
Polymerization # 1 (without CuCI2): 8.5 mg (0.86 mmol) of CuCl 0.120 ml (0.91 mmol) of 1-PECI 46.6 mg (1.74 mmol) of dTbipy 20.0 ml (0.175 mol) of styrene 20.0 g of p-dimethoxybenzeneTable 4: Poiimetation Results # 1Polymerization # 2 (3 mol% of CuCI2): 8.9 mg (0.90 mmol) of CuCl 0.4 mg (0.03 mmol) of CuCl2 0.120 ml (0.91 mmol) of 1-PEI 47.1 mg (1.75 mmol) of dTbipy 20.0 ml (0.175 mol) ) of styrene 20.0 g of p-dimethoxybenzeneTable 5: Polymerization results #Method 2: Addition of solutions for the supply of copper reagents The polymerizations were conducted as in the general procedure for the homogeneous styrene ATRP, except that the solutions of supply of the dipyridyl ligand with CuBr, and separately, CuBr2 in styrene were Prepared and added to 1-PEBr in the glass tube before removing the dry and sealed box.
Polymerization # 1 (without CuCI2): 4.5 x 10"2 mmol of CuBr 6.2 μl (4.5 x 10" 2 mmol) of 1-PErr 32.0 mg (9.0 x 10"2 mmol) of dHbipy 0.5 ml (4.36 mole) of styrene Table 6: Polymerization results # 1Polymerization # 2 (1.0 5 mole of CuBr2): 4.5 x 10"2 mmol of CuBr 4.5 x 10" 4 mmol of CuBr2 6.2 μl (4.5 x 10"2 mmol) of 1-PEr 9.0 x 10'2 mmol of dHbipy 0.5 ml (4.36 mol) of styreneTable 7: Polymerization results # 2Example 4: ATRP of water-soluble monomers General procedure for the polymerization of water-soluble monomers. Under ambient conditions, a glass tube was charged with the appropriate amounts of copper (I) halide (unpurified), bipy, initiator and monomer. The water, if used, was then added. Two "freeze-pump-thaw" cycles (described above) were performed on the contents of each tube in order to ensure that the dioxygen was removed from the polymerization solution. Each tube was sealed under vacuum, and then placed in an oil bath with thermostat at 80 ° C or 100 ° C for 12 h. Subsequently, the individual tubes were broken. (a) P (NVP). For N-vinyl pyrrolidone, the contents were dissolved in 10.0 ml of THF. The conversion percentage of each sample was measured using gas chromatography.
Volume conditions: 12.1 mg (8.4 x 10"2 mmol) of CuBr 28.1 mg (0.18 mmol) of bipy 4.0 μl (6.2 mg, 4.1 x 10" 2 mmol) of bromomethyl acetate 1.00 ml (0.980 g, 8.82 mmol) ) of N-vinyl pyrrolidone heated at 100 ° C for 12 h% conversion = 100Aqueous conditions: 13.7 mg (9.6 x 10"2 mmol) of CuBr 30.1 mg (0.19 mmol) of bipy 4.0 μl (6.2 mg, 4.1 x 10" 2 mmol) of bromomethyl acetate 1.00 ml (0.980 g, 8.82 mmol) of N-vinyl pyrrolidone 1.00 ml of water heated at 100 ° C for 12 h% conversion = 80(b) P (acrylamide). For acrylamide, the contents were dissolved in 50 ml of water and precipitated in 200 ml of CH3OH. The polymer was isolated by filtration, and the volatile materials were removed under vacuum.
Conditions: 10.7 mg (7.5 x 10"2 mmol) of CuBr 39.3 mg (0.25 mmol) of bipy 8.0 μl (12.0 mg, 7.2 x 10" 2 mmol) of methyl-2-bromopropionate 1.018 g (14.3 mmol) of acrylamide 1.00 ml of water heated at 100 ° C for 12 h. Yield: 0.325 (32%) of a white solid(c) P (HEMA). For 2-hydroxyethyl methacrylate, the contents were dissolved in 50 ml of dimethyl formamide [DMF] and precipitated in 200 ml of diethyl ether. The solvent was decanted from the oily solid, and the residue was dissolved in 25 ml of DMF. To this solution, 25 ml of acetyl chloride was added and the solution was heated to reflux for 4 h. Then, 50 ml of THF was added and the solution was emptied into 250 ml of CH 3 OH. The resulting suspension was isolated by centrifugation and the material was re-precipitated from 50 ml of THF using 250 ml of CH3OH. The molecular weight and polydispersity of the sample was measured using GPC in relation to polystyrene standards.
Conditions: 1 1.1 mg (2.1 x 10"2 mmol) of Cu (bipy) 2+ (PF6)" 6.0 μl (8.0 mg, 4.1 x 10"2 mmol) of ethyl-2-bromoisobutyrate 1.00 ml (1.07 g, 5.5 mmol) of 2-hydroxyethyl methacrylate 1 .00 ml of water heated at 80 ° C for 12 hrs Mn = 17,400; PDl = 1 .60Examples 5-8: Random copolymers The ATRP allows the preparation of random copolymers of a variety of monomers providing a wide range of well controlled molecular weight compositions, and narrow molecular weight distributions.
Example 5: Preparation of random copolymers of methyl methacrylate and styrene (a) Copolymers containing 20% styrene 0.007 g of CuBr, 0.0089 g of 2,2'-bipyridyl and 0.067 ml of ethyl-2-bromoisobutyrate were added to a mixture degassed styrene (0.25 ml) and methyl methacrylate (0.75 ml) and the reaction mixture was heated to 100 ° C. After 2.5 h, the polymerization was stopped and the resulting polymer was precipitated in methanol and purified by re-precipitating TH / methanol. The yield of the copolymer was 35%. The composition of the copolymer was determined by NMR to be% mol of styrene. The molecular weight, Mn, of the copolymer was 11,000 and the polydispersity (Mw / Mn) = 1.25, as obtained from the GPC in relation to the polystyrene standards.(b) Copolymers containing 50% styrene 0.007 g of CuBr, 0.0089 g of 2,2'-bipyridyl and 0.067 ml of ethyl-2-bromoisobutyrate were added to a degassed mixture of styrene (0.5 ml) and methyl methacrylate (0.5 ml). The reaction mixture was heated to 100 ° C. After 3.5 h, the polymerization was stopped and the resulting polymer was precipitated in methanol and purified by re-precipitating TH / methanol. The yield of the copolymer was 18%. The composition of the copolymer was determined by NMR to be 50% (mol) of styrene. The molecular weight, Mn, of the copolymer was 9,000 and the polydispersity (Mw / Mn) = 1.27, as obtained from the GPC in relation to the polystyrene standards.(c) Copolymers containing 65% styrene 0.007 g of CuBr, 0.0089 g of 2,2'-bipyridyl and 0.067 ml of ethyl-2-bromoisobutyrate were added to a degassed mixture of styrene (0.75 ml) and methyl methacrylate (0.25 ml). ml). The reaction mixture was heated to 100 ° C. After 2.0 h, the polymerization was stopped and the resulting polymer was precipitated in methanol and purified by re-precipitating TH / methanol. The yield of the copolymer was 16%. The composition of the copolymer was determined by NMR to be65% (mol) of styrene. The molecular weight, Mn, of the copolymer was 6,000 and the polydispersity (Mw / Mn) = 1.25, as obtained from the GPC in relation to the polystyrene standards.
Example 6: Copolymerization between styrene (70 mol%) and acrylonitrile (30 mol%) 2,2'-bi? Iridyl (0.1781 g), dimethoxybenzene (20 g), and Cu (l) Cl (0.0376 g) were added to a 100 ml flask, which was sealed with a rubber septum and copper wire. The flask was placed under vacuum and then back-filled with argon. This was repeated twice more. Styrene (17.2 ml) and acrylonitrile (4.2 ml) were then added via syringe. The monomers had previously been uninhibited by passing them through an alumina column and degassing by bubbling argon through the monomer for fifteen minutes. 1-phenylethyl chloride (0.0534 g) was then added to the reaction mixture by syringe, and the reaction was heated to 130 ° C. Samples were taken (0.5 ml each). The conversion was determined by 1H NMR, and Mn and polydisperity (PD) were determined by GPC. The samples were then purified by dissolution in THF and precipitation in methanol three times. The purified polymer was then evaluated for acrylonitrile content by 1 H NMR. Differences in monomer reactivities (reactivity ratio) can provide a composition gradient. Table 8 lists the results.
Table 8Example 7: Preparation of random copolymer of styrene and methyl acrylate 0.010 g of CuBr, 0.0322 g of 2,2'-bipyridyl and 0.010 ml of ethyl-2-bromoisobutyrate were added to a degassed mixture of methylacrylate (0.42 ml) and styrene ( 1.00 ml) and the reaction mixture was heated to 90 ° C. After 14 h, the polymerization was stopped and the resulting polymer precipitated in methane! and purified by re-precipitating THF / methanol. The yield of the copolymer was 87%. The composition of the copolymer was determined by NMR to be 40% (mol) of styrene. The molecular weight, M ", of the copolymer was 22,000 and the polydispersity Mw / Mn = 1.118, as obtained from GPC with respect to polystyrene standards. The proportion of monomer reactivity may have provided a composition gradient.
Example 8: Preparation of random copolymer of methyl methacrylate and butyl acrylate 0.010 g of CuBr, 0.0322 g of 2,2'-bipyridyl and 0.010 ml of ethyl-2-bromoisobutyrate were added to a degassed mixture of methyl methacrylate (2.5 ml) and butyl acrylate (2.5 ml) and the reaction mixture was heated to 10 ° C. After 2.5 h, the polymerization was stopped and the resulting polymer was precipitated in methanol and purified by re-precipitating THF / methanol. The yield of the copolymer was 53%. The composition of the copolymer was determined by NMR to be 15% (mol) of styrene. The molecular weight, Mn, of the copolymer was 1.100 and the polydispersity Mw / Mn = 1.50, as obtained from GPC in relation to polystyrene standards. The proportion of monomer reactivity may have provided a composition gradient.
Alternating and partially alternating copolymers Example 9: Alternating copolymers of isobutylene (! B) / methyl acrylate (molar feed 3.5: 1) To 0.11 g (6.68 x 10"4 mol) of 2,2'-bipyridyl and 0.36 g (2.34 x 10'4 mol) of CuBr at -30 ° C in a glass tube, were added 1.75 ml (2 x 10"2 mol) of IB, 0.5 ml (0.55 x 10" 2 mol) of methylacrylate ( MA) and 0.036 ml (2.34 x 10"4 mol) of 1-phenylethyl bromide an argon atmosphere. The glass tube was sealed under vacuum, and the reaction mixture was heated at 50 ° C for 48 hours. The reaction mixture was then dissolved in THF, and the conversion of MA as determined by GC was 100%. The polymer was then precipitated in methanol (three times), filtered, dried at 60 ° C under vacuum for 48 h and weighed. The content of IB in the copolymer was 51%, and Mn = 4050, Mw / Mn = 1.46 (Mth = 3400). The% IB in the copolymer as determined by integrating the methoxy and gem-dimethyl regions of the 1 H-NM R spectrum was 44%. The tacticity of the alternating copolymer as calculated from the methoxy proton signals according to the method described by Kuntz (J. Polym, Sci. Polym, Chem. 16, 1747, 1978) is rr / mr / mm = 46 / 28/26. The glass transition temperature of the product as determined by DSC was -28 ° C.
Example 10: Copolymer IB / MA (1: 1 molar feed) At 0.055 g (3.5 x 10"4 mol) of 2,2'-bipyridyl and 0.017 g (1.17 x 10" 4 mol) of CuBr at -30 ° C in a glass tube, 0.5 ml (0.55 x 10"2 mol) of IB, 0.5 ml (0.55 x 10" 2 mol) of methyl acrylate and 0.016 ml (1.17 x 10"4 mol) were added. 1-phenylethyl bromide in an argon atmosphere.The glass tube was sealed under vacuum, and the reaction mixture was heated at 50 ° C for 24 hours.The reaction mixture was then dissolved in THF, and the conversion of MA as described above. determined by GC was 100% .The polymer was then precipitated in methanol (three times), filtered, dried at 60 ° C under vacuum for 48 h and weighed.The content of IB in the copolymer was 28%, and Mn = 6400, Mw / Mn = 1.52 (Mth = 6500) The% IB in the copolymer as determined by integrating the methoxy and gem-dimethyl regions of the 1H-NMR spectrum according to the method described by Kuntz was 26%. glass transition temperature of Product as determined by DSC was -24 ° C.
Example 1 1: Copolymer IB / MA (molar feed 1: 3) At 0.11 g (6.68 x 10"4 mol) of 2,2'-bipyridyl and 0.36 g (2.34 x 10" 4 mol) of CuBr at -30 ° C in a glass tube, 0.5 ml (0.55 x 10"2 mol) of IB, 1.5 ml (1.65 x 10" 2 mol) of methyl acrylate (MA) and 0.036 ml (2.34 x 10"4 mol) were added. ) of 1-phenylethyl bromide in an argon atmosphere.The glass tube was sealed under vacuum, and the reaction mixture was heated at 50 ° C for 48 hours.The reaction mixture was then dissolved in THF, and the conversion of MA as determined by GC was 100% .The polymer was then precipitated in methanol (three times), filtered, dried at 60 ° C under vacuum for 48 h and weighed.The content of IB in the copolymer was 25%, and Mn = 7570, Mw / Mn = 1.58 (Mtn = 7400) The% IB in the copolymer as determined by integrating the methoxy and gem-dimethyl regions of the 1 H-NMR spectrum according to the method described by Kuntz was 24 % The glass transition temperature d The product as determined by DSC was -15 ° C.
Example 12: Alternating copolymers of isobutyl vinyl ether (lBVE) / methyl acri fate (1: 1) to 0.055 g (3.51 x 10"4 mol) of 2,2 * -bipyridite and 0.017 g (1.17 x 10" 4 mol) of CuBr in a glass tube were added 0.6 ml (0.55 x 10"2 mol) of IBVE, 0.5 ml (0.55 x 10" 2 mol) of methyl acrylate and 0.017 ml (1.17 x 10"4 mol) of 1-phenylethyl bromide under argon atmosphere The glass tube was sealed under vacuum, and the reaction mixture was heated at 50 ° C for 12 hours.The reaction mixture was then dissolved in THF, and the conversion of MA and IBVE as determined by GC it was 100% The polymer was then precipitated in methanol (three times), filtered, dried at 60 ° C under vacuum for 48 h and weighed The content of IBVE in the copolymer was 51%, and Mn = 81 10, Mw / Mn = 1.54 (Mtn = 8700) The glass transition temperature of the product as determined by DSC was -31.3 ° C.
Example 13: Copolymers of isobutyl vinyl ether / methyl acrylate (3: 1) To 0.1 1 g (6.68 x 10"4 mol) of 2,2'-bipyridyl and 0.036 g (2.34 x 10" 4 mol) of CuBr in a glass tube, 1.8 ml (1.65 x 10.2 mol) of IBVE, 0.5 ml (0.55 x 10"2 mol) of methyl acrylate and 0.034 ml (2.34 x 10" 4 mol) of 1 - were added. phenylethyl bromide under argon atmosphere. The glass tube was sealed under vacuum, and the reaction mixture was heated at 50 ° C for 12 hours. The reaction mixture was then dissolved in THF, and the conversion of MA and IBVE as determined by GC was 100%. The polymer was then precipitated in methanol (three times), filtered, dried at 60 ° C under vacuum for 48 h and weighed. The content of IBVE in the copolymer was 75%, and Mn = 8710, Mw / Mn = 2.00 (Mth = 9090). The glass transition temperature of the product as determined by DSC was -44.3 ° C and 7.1 ° C.
Example 14: Copolymers of isobutyl vinyl ether / methyl acrylate (1: 3) A 0.11 g (6.68 x 10"4 mol) of 2,2'-bipyridyl and 0.036 g (2.34 x 10" 4 mol) of CuBr in a tube of glass, 0.6 ml (0.55 x 10"2 mol) of IBVE, 1.5 ml (1.65 x 10" 2 mol) of methyl acrylate and 0.034 ml (2.34 x 10"4 mol) of 1-phenylethyl bromide were added Argon atmosphere The glass tube was sealed under vacuum, and the reaction mixture was heated at 50 ° C for 12 hours.The reaction mixture was then dissolved in THF, and the conversion of MA and IBVE as determined by GC The polymer was then precipitated in methanol (three times), filtered, dried at 60 ° C under vacuum for 48 h and weighed.The content of IBVE in the copolymer was 25%, and Mn = 7860, Mw / Mn = 1-90 (Mth = 8400) The glass transition temperature of the product as determined by DSC was -31.0 ° C and 5.6 ° C.
Periodic Copolymers Example 15: Under an argon atmosphere, 11.1 ml of styrene (9.6 x 10.2 mol) was added to 0.097 g (6 x 10"4 mol) of 2,2'-bipyridyl and 0.20 g ( 2 x 10"4 mol) of CuCl in a 50 ml glass flask. The initiator, 0.30 ml (2 x 10"4 mol) of 1-phenylethyl chloride, was then added via syringe The flask was then immersed in an oil bath at 130 ° C. At various time intervals, samples of the mixture Reactions were transferred to an NMR tube, and the styrene conversion was determined.Then, 1.5 eq of maleic anhydride (0.03 g, 3 x 10"4 mol) in benzene (4 ml) was injected into the flask at times 20, 40, 60 and 80% conversion of styrene. After 25 hours, the reaction mixture was cooled to room temperature, and 15 ml of THF was added to the samples to dissolve the polymers. The styrene conversion when measuring the residual monomer was 95%. The polymer was precipitated in dry hexane, filtered, dried at 60 ° C under vacuum for 48 h and weighed. The product had an Mn = 47500 and Mw / Mn = 1.12 (Mth = 50,000). The content of maleic anhydride was determined by IR spectroscopy, and corresponded to the amount introduced.
Gradient copolymers Example 16: Preparation of a gradient copolymer of methyl acrylate / methyl methacrylate 0.29 g of CuBr, 0.096 g of 2,2'-bipyridyl and 0.030 ml of ethyl-2-bromoisobutyrate were added to a degassed solution of methyl acrylate (2.5 ml) and methyl methacrylate (2.0 ml) in ethyl acetate (2.0 ml). The reaction mixture was controlled with a thermostat at 90 ° C and the samples were removed after 3.0 h, 5 h, 7 h and 23 h. From the composition data obtained from NMR measurements of these samples and from the evaluation of molecular weights of the GPC measurements relative to polystyrene standards, the composition gradient along the chain of the polystyrene was calculated. final copolymer (Fig. 3A-B). The final polymer (at 96% conversion) was purified by re-precipitating methanol / THF.
Example 17: 0.125 g of CuBr, 0.407 g of 2,2'-bipyridyl and 0.1 18 ml of ethyl-2-bromoisobutyrate were added to a degassed mixture of methyl acrylate (3.8 ml) and methyl methacrylate (4.8 ml). The reaction mixture was controlled with a thermostat at 80 ° C and the samples were removed after 0.5 h, 1 h and 1.5 h. From the composition data obtained from NMR measurements of these samples and from the evaluation of molecular weights of the GPC measurements relative to polystyrene standards, the composition gradient along the chain of the polystyrene was calculated. final copolymer (Fig. 4A-B). The final polymer (at 88% conversion) was purified by re-precipitating methanol / THF.
Example 18: Preparation of a styrene / methyl methacrylate gradient copolymer 0.063 g of CuBr, 0.205 g of 2,2'-bipyridyl and 0.064 ml of ethyl-2-bromoisobutyrate was added to 5 ml of styrene and the mixture was heated to 1 10 ° C. A mixture of styrene (5 ml) and methyl methacrylate (5 ml) was added at an addition rate of 0.1 ml / min, followed by 10 ml of methyl methacrylate added at the same rate. The samples were removed at certain time periods, and from the composition data obtained from the NMR measurements of these samples and from the GPC measurement of the molecular weights relative to the polystyrene standards, the composition gradient was calculated. along the chain of the final copolymer (Fig. 5A-B). The final polymer (2.34 g) was purified by re-precipitating methanol / THF. The DSC measurements of the final copolymer show a simple glass transition with Tg = 106 ° C.
Example 19: Preparation of gradient copolymer of methyl acrylate / methyl methacrylate 0.107 g of CuBr, 0.349 g of 2,2'-bipyridyl and 0.109 ml of ethyl-2-bromoisobutyrate were added to a mixture of methyl acrylate (5 ml) and methyl methacrylate (10 ml), and the reaction mixture was heated to 90 ° C. The methyl acrylate (20 ml) was added to the reaction mixture at an addition rate of 0.1 ml / min. The samples were removed at certain periods of time, and from the composition data obtained from the NMR measurements of these samples and from the GPC measurement of the molecular weights in relation to the polystyrene standards, the composition gradient along the end copolymer chain was calculated. (Fig. 6A-B). The final polymer (3.15 g) was purified by re-precipitating methanol / THF. The DSC measurements of the final copolymer show a simple glass transition with Tg = 52 ° C.
Example 20: Preparation of methyl acrylate / styrene gradient copolymers with variant composition gradient 0.603 g of CuBr, 0.250 g of 2,2'-bipyridyl and 0.64 ml of ethyl-2-bromoisobutyrate were added to 10 ml of styrene and the The reaction mixture was heated to 95 ° C. The methyl acrylate was added to the reaction mixture at an addition rate of 0.1 ml / min so that the final reaction mixture contained 90% methyl methacrylate. The samples were removed at certain time periods, and from the composition data obtained from the NMR measurements of these samples and the GPC measurement of the molecular weights relative to the polystyrene standards, the composition gradient was calculated. along the chain of the final copolymer (Fig. 7A-B). The final polymer (1.98 g) was purified by re-precipitating methanol / THF. The DSC measurements of the final copolymer show a simple glass transition with Tg = 58 ° C. In a separate experiment, 0.063 g of CuBr, 0.205 g of 2,2'-bipyridyl and 0.64 ml of ethyl-2-bromoisobutyrate were added to 10 ml of styrene and the reaction mixture was heated to 95 ° C. The methyl acrylate was added to the reaction mixture at an addition rate of 0.085 ml / min, such that the final reaction mixture contained 90% methyl methacrylate. The samples were removed at certain periods of time. From the composition data obtained from the NMR measurements of these samples and the GPC measurement of the molecular weights relative to the polystyrene standards, the composition gradient along the final copolymer chain was calculated (Fig. 8A-B). The final polymer (1.94 g) was purified by re-precipitating methanol / THF.
The DSC measurements of the final copolymer show a simple glass transition with Tg = 72 ° C. In a third experiment, 0.063 g of CuBr, 0.205 g of 2,2'-bipyridyl and 0.64 ml of ethyl-2-bromoisobutyrate were added to 10 ml of styrene and the reaction mixture was heated to 95 ° C. The methyl acrylate was added to the reaction mixture at an addition rate of 0.05 ml / min, so that the final reaction mixture contained 90% methyl methacrylate. The samples were removed at certain periods of time. From the composition data obtained from the NMR measurements of these samples and the GPC measurement of the molecular weights relative to the polystyrene standards, the composition gradient along the chain of the final copolymer was calculated (Fig. 9A-B). The final polymer (3.08 g) was purified by re-precipitating methanol / THF. The DSC measurements of the final copolymer show a simple glass transition with Tg = 58 ° C.
Example 21: Branched and hyperbranched polymers The homopolymerizations were carried out as follows: Typically, p-chloromethylstyrene, p-CMS, was polymerized in the presence of CuCl (1% relative to PCS) and 2,2'-bipyridyl (3%) , at 1 0 ° C, under oxygen-free conditions, that is, argon atmosphere. P-Chloromethylstyrene was added to a flask containing CuCI / bipyridium. Immediately on the addition of p-CMS, a slightly heterogeneous, deep red solution was obtained. The heating resulted in the color change of the solution from red to green within fifteen minutes of heating. After a period of time, the reaction was stopped and the sample was dissolved in THF. The conversion was determined by 1 H NMR, and it was found to be greater than 80%. The samples showed an almost unobservable change in viscosity at the reaction temperature, but cooling to room temperature resulted in the sample becoming solid. The green copper (ll) material was removed by passing the mixture through an alumina column. The non-precipitated samples were analyzed by GPC in relation to the polystyrene standards. Then the polymer was purified by methanol precipitation of THF. These samples were then analyzed by 1 H NMR to determine the molecular weight. Table 9 indicates the experimental results. All yields were > 70%Table 9: Homopolymerization of p-chloromethylstyrene in the presence of Cu (l) and 2,2'-bipyridylM.b Solution polymerization in benzene, [M} = 3.52 M, [CuCl} 0 = 0-.0-3-5 M. fbi yío - 0.11 M. c) Conversion based on consumption of double ligatures. d) Mn determined 1H NMR after precipitation. e) Mn, Mw determined from the complete sample, before precipitation, by GPC, using linear polystyrene standards, f) Mn by GPC, using linear polystyrene standards, after precipitation in methanol / brine.
The copolymerizations were carried out as follows: styrene (18.18 g, 20 ml) was poiimerized in a 50% w / v solution using p-dimethoxybenzene (20 g) as solvent. The amount of p-chloromethylstyrene was 2% (0.4 ml). The molar ratio of p-chloromethylstyrene / CuCl (0.2594 g) / 2,2'-bipyridyl (1.287 g) was 1: 1: 3. The solids were placed in a flask with a rubber septum and magnetic stirrer, and were degassed three times by vacuum and re-flushed with argon. The degassed monomer was added via syringe. The appropriate amount of p-chloromethyl styrene was added via syringe. The reaction was heated to 130 ° C. The reaction was quenched by precipitation in methanol. After 15 hours, the conversion was 94.3% as determined by 1 H NMR. The yield was 76%. The sample was evaluated by SEC using relative calibration, and it was found to have Mn = 13400 and Mw = 75000. By universal calibration, in conjunction with light scattering, the Mn = 31, 600 and Mw = 164,500.
Methyl methacrylate (20 ml, 18.72 g) was used in place of styrene. The reaction was run for 2 hours at 100 ° C. Mn, sEc = 44,700 and MW, SEC = 1 12,400. Mn = 58,700 (universal calibration), Mw = 141, 200 (light scattering).
Gels and cross-linked polymers Example 22: Styrene (9.09 g, 10 ml) was polymerized in a 50% (w / v) solution using p-dimethoxybenzene (10 g) as solvent. The amount of p-chloromethylstyrene was 2% (0.2 ml). The molar ratio of p-chloromethylstyrene / CuCl (0.1297 g) / 2,2'-bipyridyl (0.6453 g) was 1: 1: 3. The solids were placed in a flask with a rubber septum and magnetic stirrer, and were degassed three times by vacuum and re-flushed with argon. The degassed monomer was added via syringe, p-chloromethylstyrene was then added via syringe. The reaction was heated to 130 ° C. The reaction was quenched by precipitation in methanol. After 64.5 hours, the conversion was 94.3% as determined by HH NMR. The yield was 90%. A nebulous polymer solution was made in THF, but could not be passed through a 0.45 micron PTFE filter. On placing the solution in a centrifuge for 26 hours at 7000 rpm, the solution was clear with a light layer of solid material at the end of the bottle. The solution was passed through a 0.45 micron PTFE filter. Mn = 1 18,000, Mw / Mn = 3.74.
Example 23:The styrene (9.09 g, 10 m!) Was polymerized in a 50% (w / v) solution using p-dimethoxybenzene (10 g) as solvent. The amount of p-CMS was 10% (0.2 ml). The molar ratio of p-CMS / CuCl (0.1297 g) / 2,2'-bipyridyl (0.6453 g) was 1: 1: 3. The solids were placed in a flask with a rubber septum and magnetic stirrer, and were degassed three times by vacuum and re-flushed with argon. The degassed monomer was added via syringe. P-Chloromethyl styrene was then added via syringe. The reaction was heated to 130CC. The reaction was quenched by precipitation in methanol. After 24 hours, the conversion was 94.3% as determined by 1 H NMR. The performance was > 90% The polymer was stirred in THF but could not be dissolved. The polymer sample was placed in a soxhiet apparatus under THF reflux to remove copper salts. The sample obtained was placed in THF and allowed to reach equilibrium. The gel was determined to have an equilibrium THF content of 89%.
Example 24: Difunctional Polymers Polystyrene with two azide or bromine end groups was synthesized.
(A) a,? - dibromopolstyrene: Styrene (18.18 g, 20 ml) was polymerized in a 50% solution(w / vol) using p-dimethoxybenzene (20 g) as solvent. The α, α'-dibromo-p-xylene (1.848 g) was used as the initiator. The molar ratio of a, a'-dibromo-p-xylene / styrene / CuBr (1.00 g) / 2,2'-bipyridyl (3.28 g) was 1: 1: 3. The solids were placed in a flask with a rubber septum and magnetic stirrer, and degassed three times by vacuum and back-flushed with argon. The degassed monomer was added via syringe. The reaction was heated to 110 ° C. After 5.5 hours of conversion was > 95% as determined by 1 H NMR. The reaction was quenched by precipitation in methanol. The performance was > 90% The polymer was redissolved in THF and precipitated in methanol three times. The polymer sample was dried under vacuum at room temperature overnight. Mn, as determined by comparison of methine protons adjacent to bromine and aliphatic protons, was 2340. SEC, Mn = 2440.
(B) a,? - diazidopolystyrene: A sample of a,? - dibromopolstyrene (5.0 g) was dissolved in dry TH F (20 ml) in the presence of tetrabutyl ammonium fluoride (1 mmol F "/ g) in gel silica (6.15 g) Trimethylsilis azide (0.706 g, 0.81 ml) was then added via syringe The solution was stirred for 16 hours under argon.The 1 H NMR showed complete conversion of the methine protons adjacent to bromine to be adjacent to N3, Mn, by 1 HN MR, was 2340. Infrared spectroscopy showed a peak at 2080 cm "1, which corresponds to the azide functional group. A sample of a, β-dibromopolstyrene (4.7 mg) was placed on a DSC sample tray and heated to 250 ° C and held for 15 minutes. A series of endo and exothermic peaks were seen starting at 215 ° C. The sample was allowed to cool and enotnces dissolved in THF. The solution was injected into a SEC instrument. The Mn was 6500, an increase of 250% in molecular weight. However, the distribution was wide.
Example 25: Water-swellable polymers (A): NVP / VAc-CI polymer: N-vinylpyrrolidinone (50 ml, 48.07 g), vinyl chloroacetate (0.26 g, 0.25 ml), and AIBN (0.7102 g) were combined in a flask with round bottom, three necks, 300 ml. The monomers were degassed by bubbling argon through the mixture. The mixture was heated at 60 ° C for 1 h. The resulting solid polymer was allowed to cool and then dissolve in THF. The solution was precipitated in hexanes, and the resulting polymer was filtered and dried at 70 ° C under vacuum for three days.
(B): Hydrogel A: The NVP / VAc-CI polymer (5.0 g) of Example 25 (A) was dissolved in styrene (20 ml), in the presence of CuCl (0.041 1 g) and 4,4'-di -t-butyl-2,2'-bipyridyl (0.2224 g), under oxygen-free conditions. The reaction mixture was heated to 130 ° C. After 30 minutes, the reaction mixture became gelatinous. The mixture was dissolved in DMF and precipitated in water. A mass similar to a gel was obtained and filtered. The resulting solid was a gel weighing 20.0 g. The gel was dried over P2Os at 70 ° C under vacuum for 2.5 days. The yield was 4.0 g.
(O: Hydrogel B: The NVP / VAc-CI polymer (5.0 g) of Example 25 (A) was dissolved in styrene (20 ml), in the presence of CuC! (0.0041 g) and 4,4'-di- t-butyl-2,2'-bipyridyl (0.0222 g), under oxygen-free conditions.The reaction mixture was heated to 130 ° C. After two hours, the reaction mixture became gelatinous.The reaction was stirred for three hours more until the mixture was so viscous that the magnetic stir bar did not spin.The mixture was dissolved in DMF and precipitated in water.A gel-like mass was obtained and filtered.The resulting solid was a gel having a mass of 20.0 g The gel was dried over P2O5 at 70 ° C under vacuum for 2.5 days.The yield was 4.0 g.
(D): Styrene macromonomers: (i): Synthesis of polystyrene with a terminal group of vinyl acetate (VAc-styrene) Polystyrene 5K: Cu (l) CI (0.5188 g) and 2, 2'-bipyridyl (2.40 g) were added to a 100 ml round bottom flask and sealed with rubber septum. The contents of the flask were placed under vacuum, then re-flushed with argon. This was repeated two additional times. Diphenyl ether (30.0 ml), uninhibited styrene (30.0 ml) and vinyl chloroacetate (0.53 ml), all of which were previously degassed by bubbling argon through the liquids, were added to the flask via syringe. The reaction mixture was then heated at 130 ° C for 6 hours. The reaction mixture was then transferred into methanol to precipitate the formed polymer. Then, the precipitate was re-precipitated twice from THF in methanol. The isolated white powder was then dried under vacuum at room temperature. Yield: 21.68 g (77.4%). GPC: Mn = 4400, PD = 1.22.10K polystyrene: Cu (l) CI (0.5188 g) and 2,2'-bipyridyl (2.40 g) were added to a 250 ml round bottom flask and sealed with a rubber septum. The contents of the flask were placed under vacuum, and then re-flushed with argon. This was repeated twice more. Diphenyl ether (60.0 ml), uninhibited styrene (60.0 ml) and vinyl chloroacetate (0.53 ml), all of which were previously degassed by bubbling argon through the liquids, were added to the flask via syringe. The reaction mixture was then heated at 130 ° C for 24 hours. The reaction mixture was then transferred to methanol to precipitate the formed polymer. The precipitate was re-precipitated twice from THF in methanol. The isolated white powder was then dried under vacuum at room temperature. Yield: 44.36 g (81.3%). GPC: Mn = 10,500, PD = 1.25.(ii): Synthesis of water-swellable polymers Copolymerization of N-vinyl pyrrolidinone (75% by weight) with VAc-styrene(Mn = 4400: 25% by weight):AIBN (0.0106 g) and VAc-styrene (2.50 g) were added to a 50 ml round bottom flask and sealed with a rubber septum. The contents of the flask were placed under vacuum and re-argonlated with argon three times. DMSO previously degassed (20.0 ml) and N-vinyl pyrrolidinone (7.5 ml) were added to the flask by syringe. The reaction was then heated at 60 ° C for 20 hours. A highly viscous fluid was obtained and diluted with DMF (30.0 ml). The reaction mixture was precipitated in water. The precipitate was a swollen solid. This was filtered and dried under vacuum at 70 ° C to produce the obtained polymer. The obtained polymer was placed in a water bath for 3 days. The equilibrium water content was 89%.
Copolymerization of N-vinyl pyrrolidinone (75% by weight) with VAc-styrene (Mn = 10500. 25% by weight) A1BN (0.0106 g) and VAc-styrene (2.50 g) were added to a 50 ml round bottom flask and sealed with a rubber septum. The contents of the flask were placed under vacuum and re-flushed with argon three times. The previously degassed DMSO (20.0 ml) and N-vinyl pyrrolidinone (7.5 ml) were added to the flask by syringe. The reaction was then heated at 60 ° C for 20 hours. A highly viscous fluid was obtained and diluted with DMF (30.0 ml). The reaction mixture was precipitated in water. The precipitate was a white mass, similar to jelly. The liquid was decanted, the precipitate was dried with air overnight, and then dried under vacuum at 70 ° C to produce the obtained polymer. Mn = 1 16,000; PD = 2.6.
After being placed in a water bath for 3 days, the equilibrium water content was determined to be 89%.
Example 26: Thiocyanate Transfer Polymerizations It has previously been reported that thiocyanate (SCN) is transferred from Cu (SCN) 2 to an alkyl radical at about the same rate as CuCl 2 chloride (Kochi et al., J. Am. Chem. Soc, 94, 856, 1972). A 3: 1: 1 molar ratio of ligand (2,2'-bipyridolo [bipy] or 4,4'-di- n-hepti! -2,2'-bipyridyl [dHbipy]) to initiator (PhCH2SCN) to Transition metal compound (CuSCN) was used for each polymerization. The initiator system components were weighed and combined in air under ambient conditions. The reactions were run in bulk according to the procedure of Example 4, but at 120 ° C. The reactions using bipy were very viscous after 5 h, at which time they were cooled to room temperature. The reactions using dHbipy were not viscous after 5 h, and were heated accordingly for 24 h before cooling to room temperature.
The results are shown in Table 10 below.
Table 10where "M / l" is the monomer / initiator ratio, "% conv." it refers to the percentage of conversion, and "PDI" refers to polydispersity. The bipy reactions showed less control than the optimal molecular weight control, but the dHbipy reactions showed excellent molecular weight control. It is believed that PDI can be further improved by increasing the amount or concentration of Cu (11) at the start of the polymerization.
Example 27: Synthesis of PSt in the form of a comb The initiator of macro ATRP, poly (p-chloromethylstyrene), PCMs, was synthesized by polymerizing p-chloromethylstyrene (0.02 mol) in benzene (50%) at 60 ° C for 24 hours using ICH2CN (0.0023 mo!) And AIBN (0.0006 mol). Yield 92%. Mn = 1150, Mw / Mn = 1 .20. Subsequently, a degassed solution containing St(0.012 mol), purified PVBC (9.6 x 10"5 mol), CuCl (1.5 x 10'4 mol) and beep (4.5 x 10" 4 mol) was heated at 130 ° C for 18 h. PSt was obtained in the form of a comb (yield = 95%). Mn = 18500, Mw / Mn = 1.40. At lower initial concentrations of PCMS, comb-shaped polystyrenes of higher molecular weight were formed (Mn = 40,000 and 80,000 g / mol, as compared to linear polystyrene standards, cf. the first three entries in Table 15).
Example 28: Synthesis of PVAc-g-PSt PSt was synthesized terminally capped with vinyl acetate (PSt-VAc) by polymerization of St (0.019 mol) in bulk at 130 ° C for 18 h using CICH2COOCH = CH2 (0.0018 mol), CuCl (0.0018 mol) and beep (0.0054 mol). Yield: 95%. Mn = 1500, Mw / Mn = 1.35. Subsequently, a degassed solution containing vinyl acetate (5.8 x 10"3 mol), purified PSt-VAc (6.67 x 10" 5 mol) and AIBN (1 x 10"4 mol) in ethyl acetate was heated at 60 ° C for 48 hours. h (ca 85% conversion of macromonomer) Final graft copolymer composition: Mn = 54500, Mw / Mn = 1.70.
Example 29: Terminal Functional Polymers One of the advantages of the ATRP process is that one can synthesize well-defined functional terminal polymers by using functional alkyl halides and transition metal species (Scheme 4).
Z - (R ') - X + n = Mf; L * z ~ + XScheme 4Tables 1 1 and 12 report the characterization data of St ATRPs using various functional alkyl halides as initiators under typical experimental conditions of ATRP. From Table 11, it appears that alkyl halides containing acid give an increase to relatively uncontrolled polymers (eg, limited conversions, molecular weights greater than expected, and relatively broad molecular weight distributions). This suggests that CuCl can react with these alkyl halides with formation of side products, which disturb the "living" ATRP process. Using 3-chloro-3-methyl-1-butine, the monomer conversion was almost quantitative. However, the experimental molecular weight is ca. 3 times as high as expected, and the polydispersity is as high as 1.95. This suggests that the initiation is slow and the triple ligature could also be attacked by the radicals in formation. In addition, using 2- (bromomethyl) naphthalene and 9- (chloromethyl) anthracene as initiators, the polymers obtained showed properties as good as the polymers obtained by using 1-alkyl-2-phenylethyl halide initiators. However, 1,8-bis (bromomethyl) naphthalene does not appear to be as efficient as an ATRP initiator such as 2- (bromometii) naphthalene and 9- (cyoromethyl) anthracene under the same conditions. More importantly, several Pst macromonomers containing polymerizable double bonds can be obtained in a controlled manner (Table 11). The 1 H NMR spectrum of Pst started with vinyl chloroacetate in the presence of 1 equiv. molar of CuCl and 3 equiv. bipy molars at 130 ° C shows signals at 4.0 to 5.5 ppm, assigned to vinyl end groups. A comparison of the integration of vinyl protons with the protons in the backbone gives a molecular weight similar to the molecular weight obtained from SEC; that is, a functionality close to 0.90. This suggests that the double ligation is not reactive towards a minute amount of St-type radicals during St. ATRP.
Table 11: ATRP synthesis of terminal functional polymers8a) Polymerization conditions: molar ratio of RX / CuX / Bpy: 1/1/3; temp: CI-ATRP, 130 ° C; Br-ATRP, 1 10 ° C. b) Calculated based on Mn = MD x (D [M] / [RX] 0).
Example 30: Sequential Block Copolymerization ATRP can also be used successfully to produce well-defined di- and tri-block copolymers by sequential addition technique. As seen in Table 12., the di- and tri-block copolymers of St and MA obtained are very well defined, despite the order of monomer addition. The molecular weights are close to the theoretical ones, and the molecular weight distributions remain very narrow, Mw / Mp from ~ 1.0 to ~ 1.25. The traces of SEC show that almost no first polymer contaminates the final block copolymer. The DSC measurements of several samples in Table 12 were also made. It appears to be two glass transition temperatures around 30 ° C and 100 ° C, very close to the Tg of PMA and PSt, respectively. The NMR analysis of the purified polymer also shows the presence of PMA and PSt segments. All these results indicate that well-defined block copolymers have been synthesized.
Table 12: Synthesis of di- and tri-block copolymers through sequence addition! 3a) All polymerizations were performed at 1 10CC. b) Initiators used: di-block copolymer: 1-phenylethyl bromide; tri-block copolymers: a, a'-dibromoxyleneATRP is superior for living ion polymerization to produce well controlled block copolymers. First of all, the experimental conditions are relatively mild. In addition, cross-propagation is easy, leading to block copolymerization despite the order of addition of monomers, as exemplified by the copolymerization of MA and earlier St. Moreover, the tri-block copolymers can be easily obtained by using a di-functional initiator. As expected, the star-block copolymers can be obtained by using multi-functional alkyl halides.
Example 31: Star-shaped polymer (i) PSt synthesis with 4 and 6-star star shape using 1, 2,4,5-tetrakis (bromomethyl) benzene and hexakis (bromomethyl) benzene as initiator. Table 13 lists the results with respect to the synthesis of 4-arm and six-arm star-shaped PSt using 1, 2,4,5-tetrakis (bromomethyl) benzene and hexakis (bromomethyl) benzene as initiator, respectively. The definitely narrow molecular weight distribution, ie, Mw / Mn < 1.3. The Mn of these star-shaped polymers increases linearly with the monomer conversion, indicating the presence of negligible amount of chain in transfer reactions (data not shown). A key issue involves whether the polymers in formation have six or four arms. Thus, deuterated styrene ATRP was performed using hexakis (bromomethyl) benzene as an initiator in the presence of 2 equiv. molars of CuBr and 6 equiv. bipy molars at 1 10 ° C, the same experimental conditions used to synthesize the PSt of six arms listed in Table 13. Except for the observation of a resonance -CH2- at ca. 1.55 ppm, the 1H NMR signals corresponding to -CH2Br, which usually resonate at ca. 5.0 ppm, they could not be detected at all in the 1 H NMR spectrum of PSt-d8. This provides strong evidence that up six-arm PSt-d8 was produced.
Table 13: Synthesis of PSt of 4 and 6 arms using C6H2 (CH2-Br) 4 and C6 (CH2-Br) as initiators at 110 ° Ca: [R-Br] 0 / [CuBr] 0 / [bpy] or = 1/2/6; b: six arms; c: four arms(ii) Synthesis of PMA and PMMA with 4 and 6 arms star shape using 1, 2,4,5 tetrakis (bromomethyl) benzene and hexakis (bromomethyl) benzene as initiator. As noted in Table 14, PMA and PMMA of 4 and 6 arms can also be synthesized by using the same technique for star-shaped St polymerization. However, it may be advantageous to lower the concentration of the catalyst (for example, CuBr-bipy), otherwise gelation may occur at a relatively low monomer conversion. This seems to confirm the radical process of ATRP. On the other hand, it also suggests that the compact structure of the growing polymer chains can affect the "living" course of ATRP, since at the same concentration of initiating system, the ATRP of MA and MMA represents a fairly controlled process, when a monofunctional initiator was used.
Table 14: Synthesis of PMA and PMMA of 4 and 6 arms using C6H2 (CH2-Br) 4 and C6 (CH2-Br) 4 as initiators at 1 10 ° Ca: Polymerization at 1 10 ° C.
Example 32: Well-defined comb-shaped PSt graft technique has been successfully obtained using PCMS as an ATRP initiator. Table 15 shows the SEC results of the final polymers. The MWD is quite narrow.
Table 15: Synthesis of graft copolymers using PCMS < DPp = 1 1) as initiator8a: Polymerization at 130 ° C in bulk. b: Taken from example 27. c: Polymerization in 50% ethyl acetate solution.
Similar to the 4 and 6 arm polymers; A key question is whether all the chlorine atoms in PCMS participate in the ATRP. A comparison of the 1 H NMR spectrum of PCMS and PSt-d8-g-PCMS shows that the resonances at ca. 5 ppm, corresponding to CH2CI in PCMS, disappeared completely, suggesting the formation of pure PSt-copolymer comb.
Example 33: Synthesis of ABA block copolymers with B = 2-ethylhexyl acrylate (a) Synthesis of central block B (α, α-dibromopoly (2-ethylhexylacrylate)) To a 50 ml round bottom flask, CuBr ( 0.032 g), dTBipy (0.129 g), a'-dibromo-p-xylene (0.058 g). The flask was then sealed with a rubber septum. The flask was degassed by applying a vacuum and re-controlling with argon. Degassed and uninhibited racemic 2-ethylhexyl acrylate (10.0 ml) was then added via syringe. The degassed diphenyl ether (10.0 ml) was also added by syringe. The reaction was heated to 100 ° C and stirred for 24 hours. The conversion by 1H NMR was > 90% Mn = 40,500; Mw / Mn = 1.35.(b) A = Methyl methacrylate To the reaction mixture obtained in Example 33 (a) containing the poly (2-ethylhexyl acrylate), methyl methacrylate (4.53 ml) was added via syringe. The reaction was stirred at 100 ° C for 8 hours. The MMA conversion was > 90% Mn (global) = 58,000; Mw / Mn = 1 .45.(c) A = acrylonitrile The experiment of Example 33 (a) was repeated. To the reaction mixture containing the (2-ethylenehexyl acrylate) (Mn = 40,500; Mw / Mn = 1.35), acrylonitrile (5.44 ml) was added via syringe. The reaction was stirred to100 ° C for 72 hours. Conversion of acrylonitrile = 35%. Mn (global) =47,200; Mw / Mn = 1.45.
Example 34: Synthesis of block copolymer MMA-BA-MMA Synthesis of a,? -dibromopoly (butyl acrylate):To a 50 ml round bottom flask, were added a, -dibromo-p-xylene (0.0692 g), CuBr (0.0376 g), and 2,2, -bipyridyl (0.1229 g) and sealed with a septum rubber. The flask was then evacuated and filled with argon three times. Pre-degassed butyl acrylate (15.0 ml) and benzene (15.0 ml) were added via syringe. The reaction was heated to 100 ° C for 48 hours, after which time the conversion was 86.5%, as determined by 1 H NMR. The reaction mixture was poured into cold methanol (-78 ° C) to precipitate the polymer. The precipitate was filtered. The solid obtained was a highly viscous, sticky oil, Mn = 49,000,Synthesis of poly (MMA-BA-MMA): In a round bottom flask, were added α, β-dibromopoly (butyl acrylate) (2.0 g), CuBr (0.0059 g), 2,2-bipyridyl (0.0192 g) and dimethoxybenzene (2.0 g). The flask was sealed with a rubber septum and placed under an argon atmosphere as described above for the synthesis of a, β-dibromopoly (butyl acrylate). Degassed methyl methacrylate (0.73 ml) was added via syringe. The reaction was heated at 100 ° C for 5.25 hours. The conversion was determined to be 88.8% by 1 H NMR. The reaction mixture was poured into methanol to precipitate the polymer. The solid, which was obtained, was colorless and elastic. Mn = 75,400, Mw / Mn = 1 .34.
Example 35: Synthesis of poly (pt-butylstyrene) To a 100 ml round bottom flask, dimethoxybenzene (25.0 g), CuCl (0.2417) and 2,2'-bipyridyl (1170 g) were added and sealed with a septum. rubber. The flask was then evacuated and filled with argon three times. Degassed t-butylstyrene (28.6 ml) and 1-phenylethyl chloride (0.33 ml) were added via syringe. The reaction was then heated at 130 ° C for 8.5 hours. The reaction mixture was precipitated in methanol, filtered and dried. Mn = 5531. Mw / Mn = 1.22.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. Therefore, it should be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.