A kind of preparation method of dioctadecyl terephthalateTechnical field
The invention belongs to high molecular material Organic Ingredients fields, and it is organic to be related to the high molecular materials such as polyester, polyurethane, coatingThe preparation method of raw material technical field more particularly to a kind of bis- (3- hydroxyl -2, the 2- dimethyl propyl) esters of terephthalic acid (TPA).
Background technique
Bis- (3- hydroxyl -2, the 2- dimethyl propyl) esters of terephthalic acid (TPA) are a kind of organic compounds containing double hydroxy functional groupsObject, its main feature is that β carbon in molecule on neopentyl not hydrogen atoms, can assign production applied to polyester, polyurethane or paint fieldThe preferable thermolytic mechanism of product and stability to hydrolysis resistance, and can be used for biodegradation material field, there is good answerUse prospect.The method that existing preparation method mainly has following report:
(1) United States Patent (USP) US6600010B2 is using paraphthaloyl chloride and excessive neopentyl glycol in the presence of potassium carbonateIt is reacted in solvent, costly, solvent usage amount is more for this method raw material paraphthaloyl chloride.
(2) Xiang Zhu etc., Polym.Chem., 2017,8,1953, using dimethyl terephthalate (DMT) and 50 times of chemistryThe neopentyl glycol for measuring ratio reacts under zinc acetate catalysis, and this method neopentyl glycol dosage is excessive, and post-processing is difficult, is unfavorable for bigLarge-scale production.
(3) Mukesh Kathalewar etc., Progress in Organic Coatings 2013,76,147-156,Alcoholysis is carried out to polyester using a large amount of neopentyl glycols, by-product is more in products therefrom, and more difficult purifying, product purity are low.
(4) Liao Dezhong etc., applied chemistry, 2010,27 (02), 159-163 are anti-with paraphthaloyl chloride using neopentyl glycolIt answers, products therefrom is the mixture of oligomer, and component is not readily separated.
To sum up, cost of material used by these existing methods is high or product purification is difficult, and purity is low, is unfavorable for criticizingAmount production.
Therefore, how to solve the above problems, be those skilled in the art the content of important research.
Summary of the invention
To overcome the deficiencies in the prior art described above, it is an object of that present invention to provide kind of terephthalic acid (TPA) it is bis- (hydroxyl -2 3-,2- dimethyl propyl) ester preparation method, this method product purity is high, at low cost, is suitable for batch production.
In order to achieve the above objects and other related objects, the present invention provides a kind of bis- (3- hydroxyls -2,2- bis- of terephthalic acid (TPA)Methyl-propyl) ester preparation method, including following reaction process:
The preparation method comprises the following steps:
The dimethyl terephthalate (DMT) and neopentyl glycol for being 1mol:2.2~15mol by molar ratio, in catalyst Ti acid estersIn the presence of, 170 DEG C~200 DEG C at a temperature of react 4~12h；After reaction, excessive neopentyl glycol is steamed,It carries out being recrystallized to give bis- (3- hydroxyl -2,2- dimethyl propyl) the ester products of terephthalic acid (TPA) in solvent.
In above scheme, related content is explained as follows:
1, in above scheme, the catalyst Ti acid esters is butyl titanate or tetraisopropyl titanate, the catalyst TiThe quality of acid esters is dimethyl terephthalate (DMT) quality 0.02%~0.8%.
2, in above scheme, the excessive neopentyl glycol 130 DEG C~160 DEG C at a temperature of vacuumize and steam.
3, in above scheme, the recrystallization solvent for use is one or both of methylene chloride or acetone.
Since above-mentioned technical proposal is used, compared with the prior art, the invention has the beneficial effects that:
Raw material of the present invention is easy to get, and solvent has good industrial prospect using few, good economy performance, product purity height.ThisInventive method has substantive distinguishing features outstanding and significant progress.
Figure of description
Fig. 1 is preparation gained bis- (3- hydroxyl -2, the 2- dimethyl propyl) esters of terephthalic acid (TPA) in the specific embodiment of the invention 2Infrared spectrogram (attenuated total reflection).
Specific embodiment
Embodiment is given below so that the present invention to be specifically described, it is necessary to which indicated herein is that following embodiment is only usedIn invention is further explained, it should not be understood as limiting the scope of the invention, the people that is skilled in technique of this fieldMember still belongs to protection model of the invention according to some nonessential modifications and adaptations that the content of aforementioned present invention makes the present inventionIt encloses.Embodiments of the present invention are illustrated by particular specific embodiment below, those skilled in the art can be by this specification instituteThe content of exposure is understood other advantages and efficacy of the present invention easily.
Embodiment:
A kind of preparation method of bis- (3- hydroxyl -2, the 2- dimethyl propyl) esters of terephthalic acid (TPA), including following reaction process:
The preparation method comprises the following steps:
The dimethyl terephthalate (DMT) and neopentyl glycol for being 1mol:2.2~15mol by molar ratio, in catalyst Ti acid estersIn the presence of, 170 DEG C~200 DEG C at a temperature of react 4~12h；After reaction, excessive neopentyl glycol is steamed,It carries out being recrystallized to give bis- (3- hydroxyl -2,2- dimethyl propyl) the ester products of terephthalic acid (TPA) in solvent.
The catalyst Ti acid esters is butyl titanate or tetraisopropyl titanate, and the quality of the catalyst Ti acid esters is pairRutgers quality 0.02%~0.8%.
The excessive neopentyl glycol 130 DEG C~160 DEG C at a temperature of vacuumize and steam.
The recrystallization solvent for use is one or both of methylene chloride or acetone.
The specific embodiment 1 implemented according to above-mentioned preparation method:
Dimethyl terephthalate (DMT) 485.5g (2.50mol) is added in there-necked flask, neopentyl glycol 572.9g (5.5mol),140 DEG C are risen under nitrogen protection, and 0.3g butyl titanate is added, is slowly heated to 195 DEG C, and react 4h at this temperature；Reaction solution is cooled to 135 DEG C~150 DEG C, after vacuum distillation removes excessive neopentyl glycol, is cooled to room temperature, gained crude product is addedIn 1.5L methylene chloride, freezing and crystallizing, filtering is dried in vacuo to obtain white crystal, yield 29%.By infrared spectroscopy, liquid phase colorIt composes and is determined as bis- (3- hydroxyl -2, the 2- dimethyl propyl) esters of pure terephthalic acid (TPA), 120.5 DEG C~121.3 DEG C of fusing point.
The specific embodiment 2 implemented according to above-mentioned preparation method:
Dimethyl terephthalate (DMT) 310g (1.60mol) is added in there-necked flask, neopentyl glycol 665g (6.4mol), in nitrogen140 DEG C are risen under gas shielded, and 2.5g tetraisopropyl titanate is added, is slowly heated to 185 DEG C, and react 8h at this temperature；It willReaction solution is cooled to 140 DEG C~160 DEG C, after vacuum distillation removes excessive neopentyl glycol, is cooled to room temperature, and gained crude product is addedIn 1.5L methylene chloride, freezing and crystallizing, filtering is dried in vacuo to obtain white crystal, yield 55%.By infrared spectroscopy, liquid phase colorSpectrum is determined as bis- (3- hydroxyl -2, the 2- dimethyl propyl) esters of pure terephthalic acid (TPA).
The specific embodiment 3 implemented according to above-mentioned preparation method:
Dimethyl terephthalate (DMT) 130g (0.67mol) is added in there-necked flask, neopentyl glycol 837g (8.0mol), in nitrogen140 DEG C are risen under gas shielded, and 0.5g butyl titanate is added, is slowly heated to 180 DEG C, and react 12h at this temperature；It will be anti-It answers liquid cooling to 140 DEG C~160 DEG C, after vacuum distillation removes excessive neopentyl glycol, is cooled to room temperature, dichloro is added in gained crude productIn methane, freezing and crystallizing, filtering is dried in vacuo to obtain white crystal, yield 79%.It is determined as by infrared spectroscopy, liquid chromatogramBis- (3- hydroxyl -2, the 2- dimethyl propyl) esters of pure terephthalic acid (TPA).
The specific embodiment 4 implemented according to above-mentioned preparation method:
Dimethyl terephthalate (DMT) 105g (0.54mol) is added in there-necked flask, neopentyl glycol 845g (8.1mol), in nitrogen140 DEG C are risen under gas shielded, and 0.4g butyl titanate is added, is slowly heated to 185 DEG C, and react 12h at this temperature；It will be anti-It answers liquid cooling to 140 DEG C~160 DEG C, after vacuum distillation removes excessive neopentyl glycol, is cooled to room temperature, gained crude product is addedIn 500mL acetone, freezing and crystallizing, filtering is dried in vacuo to obtain white crystal, yield 76%.It is true by infrared spectroscopy, liquid chromatogramIt is set to bis- (3- hydroxyl -2, the 2- dimethyl propyl) esters of pure terephthalic acid (TPA).
Raw material of the present invention is easy to get, and solvent has good industrial prospect using few, good economy performance, product purity height.ThisInventive method has substantive distinguishing features outstanding and significant progress.
The above-described embodiments merely illustrate the principles and effects of the present invention, and is not intended to limit the present invention.It is any ripeThe personage for knowing this technology all without departing from the spirit and scope of the present invention, carries out modifications and changes to above-described embodiment.CauseThis, institute is complete without departing from the spirit and technical ideas disclosed in the present invention by those of ordinary skill in the art such asAt all equivalent modifications or change, should be covered by the claims of the present invention.