技术领域Technical Field
本发明属于胶粘剂技术领域，具体涉及一种人造板无醛胶的制备方法与应用。The invention belongs to the technical field of adhesives, and in particular relates to a preparation method and application of formaldehyde-free adhesive for artificial boards.
背景技术Background Art
胶粘剂在木材工业中起着至关重要的作用。胶粘剂用量已成为衡量一个国家或地区木材工业技术水平的重要指标。随着我国国民经济的发展和人民生活水平的不断提高，社会对木材和木制品的需求将大大增加。因此，胶粘剂的使用量也急剧增加。Adhesives play a vital role in the wood industry. The amount of adhesives used has become an important indicator to measure the technical level of a country or region's wood industry. With the development of my country's national economy and the continuous improvement of people's living standards, the society's demand for wood and wood products will greatly increase. Therefore, the use of adhesives has also increased dramatically.
随着我国天然林保护工程的进一步实施，中小型木材的数量将越来越多。因此，利用中小型木材、木材加工残留物和森林采伐残留物生产各种人造板将成为我国木材工业发展的重点。因此，我国人造板产品必须不断提高质量，降低成本，才能在市场竞争中立于不败之地。而人造板产品的质量水平和市场竞争力很大程度上取决于胶粘剂的生产水平。胶粘剂的质量对人造板的产品质量有着重要的影响。粘合剂的成本在人造板的整个生产成本中占很大份额。粘合剂的成本无法降低，则无法降低人造板的成本。因此，人造板胶粘剂的开发显得越来越重要。With the further implementation of my country's natural forest protection project, the number of small and medium-sized wood will increase. Therefore, the production of various wood-based panels using small and medium-sized wood, wood processing residues and forest felling residues will become the focus of my country's wood industry development. Therefore, my country's wood-based panel products must continuously improve quality and reduce costs in order to remain invincible in market competition. The quality level and market competitiveness of wood-based panel products depend to a large extent on the production level of adhesives. The quality of adhesives has an important impact on the product quality of wood-based panels. The cost of adhesives accounts for a large share of the entire production cost of wood-based panels. If the cost of adhesives cannot be reduced, the cost of wood-based panels cannot be reduced. Therefore, the development of wood-based panel adhesives is becoming more and more important.
目前，我国胶粘剂行业存在的主要问题表现在以下几个方面：（1）粘合剂中游离甲醛含量高，导致人造板产品中甲醛释放过多。由于人造板产品在我国室内装饰和家具行业的广泛使用，这一问题已直接成为影响人类健康的社会问题，并在社会各界造成了非常负面的印象。此外，粘合剂中的其他有害成分，如苯酚，对人类健康和环境有重大影响。如果这些问题得不到妥善解决，将对我国人造板产品的销售产生严重影响。（2）我国的胶粘剂生产大多依赖于人造板生产企业，这些企业自己生产和自己使用。这种小规模的农业生产方式不利于胶粘剂行业的发展。我国大多数人造板生产企业规模相对较小，且独立经营，小厂经营很少有能力认真对待粘合剂的生产和质量问题。（3）胶粘剂生产工艺落后，质量不稳定，对原材料和胶粘剂设备适应性差。由于粘合剂本身固有的质量问题，为了确保人造板产品的质量，只能通过增加粘合剂的用量来解决。过度使用胶水是人造板生产成本无法降低的主要原因。At present, the main problems existing in my country's adhesive industry are manifested in the following aspects: (1) The high content of free formaldehyde in adhesives leads to excessive formaldehyde release in wood-based panel products. Due to the widespread use of wood-based panel products in my country's interior decoration and furniture industries, this problem has directly become a social problem that affects human health and has created a very negative impression in all sectors of society. In addition, other harmful components in adhesives, such as phenol, have a significant impact on human health and the environment. If these problems are not properly resolved, they will have a serious impact on the sales of my country's wood-based panel products. (2) my country's adhesive production mostly depends on wood-based panel manufacturers, which produce and use them themselves. This small-scale agricultural production method is not conducive to the development of the adhesive industry. Most of my country's wood-based panel manufacturers are relatively small in scale and operate independently. Small factories rarely have the ability to seriously deal with adhesive production and quality issues. (3) The adhesive production process is backward, the quality is unstable, and the adaptability to raw materials and adhesive equipment is poor. Due to the inherent quality problems of the adhesive itself, in order to ensure the quality of wood-based panel products, it can only be solved by increasing the amount of adhesive. Excessive use of glue is the main reason why the production cost of wood-based panels cannot be reduced.
目前我国人造板行业主要使用脲醛胶、酚醛胶、以及三聚氰胺甲醛胶，是由于其原材料来源丰富、合成工艺简单以及成本较低廉。从胶粘剂的名称就可以看出这些胶粘剂都包含有醛基结构的“含醛胶”，干燥过程中会释放“游离甲醛”。当使用这些胶粘剂的人造板被应用于室内装饰和家具行业时，释放的挥发性醛类物质会对自然环境以及人体健康造成损害，直接成为影响人类健康的社会问题。At present, my country's artificial board industry mainly uses urea-formaldehyde glue, phenol-formaldehyde glue, and melamine-formaldehyde glue because of their abundant raw material sources, simple synthesis process and low cost. From the name of the adhesive, it can be seen that these adhesives all contain "aldehyde-containing glue" with aldehyde structure, which will release "free formaldehyde" during the drying process. When artificial boards using these adhesives are used in interior decoration and furniture industries, the volatile aldehyde substances released will cause damage to the natural environment and human health, and directly become a social problem affecting human health.
随着人们对改善生活条件的追求和环保意识的提高，基于环保的角度，市场上也出现了一些甲醛释放为零的聚氨酯胶粘剂和大豆蛋白胶粘剂。虽然聚氨酯粘合剂固化速度快，但其成本高，而且还容易受到环境温度和湿度的影响。而且，过快的固化速度使得胶体的应用时间非常短，容易粘附在模板和传送带上，这对生产线的要求很高，难以控制胶体的用量，提高了生产成本。大豆蛋白粘合剂是以大豆为原料制备的粘合剂，虽然它相对便宜，但它含有淀粉和蛋白质等有机成分，这些成分的存在使得人造板很容易受到空气中细菌和霉菌的侵蚀，导致斑块和霉菌生长，而且其结合强度、耐水性和耐候性也较差。With the pursuit of improved living conditions and the improvement of environmental awareness, some polyurethane adhesives and soy protein adhesives with zero formaldehyde emission have appeared on the market from the perspective of environmental protection. Although polyurethane adhesives have a fast curing speed, they are expensive and are easily affected by ambient temperature and humidity. Moreover, the too fast curing speed makes the application time of the colloid very short, and it is easy to adhere to the template and conveyor belt, which places high requirements on the production line, makes it difficult to control the amount of colloid, and increases production costs. Soy protein adhesive is an adhesive prepared from soybeans. Although it is relatively cheap, it contains organic components such as starch and protein. The presence of these components makes the artificial board easily eroded by bacteria and mold in the air, resulting in plaque and mold growth, and its bonding strength, water resistance and weather resistance are also poor.
综上所述，本发明提供一种人造板无醛胶的制备方法与应用，采用本发明方法制备得到的胶粘剂不含醛基，使用此胶粘剂的人造板可以达到甲醛零释放的效果；上述无醛胶在制备的过程中引入功能单体，使得无醛胶具备一定的抗菌与阻燃的功效；此外，在无醛胶的制备采用三阶段的聚合方式，控制极低的单体残留，使得无醛胶无异味，是一种环保且综合性能优异的胶粘剂。In summary, the present invention provides a preparation method and application of formaldehyde-free glue for artificial boards. The adhesive prepared by the method of the present invention does not contain aldehyde groups, and the artificial boards using this adhesive can achieve the effect of zero formaldehyde release; the above-mentioned formaldehyde-free glue introduces functional monomers during the preparation process, so that the formaldehyde-free glue has certain antibacterial and flame retardant effects; in addition, a three-stage polymerization method is adopted in the preparation of the formaldehyde-free glue to control extremely low monomer residues, so that the formaldehyde-free glue has no odor, and is an environmentally friendly adhesive with excellent comprehensive performance.
发明内容Summary of the invention
针对以上现有技术的不足，本发明的目的在于开发一种人造板无醛胶的制备方法与应用，采用本发明方法制备得到的胶粘剂不含醛基，使用此胶粘剂的人造板可以达到甲醛零释放的效果；上述无醛胶在制备的过程中引入功能单体，使得无醛胶具备一定的抗菌与阻燃的功效；此外，在无醛胶的制备采用三阶段的聚合方式，控制极低的单体残留，使得无醛胶无异味，是一种环保且综合性能优异的胶粘剂。In view of the deficiencies of the above-mentioned prior art, the purpose of the present invention is to develop a preparation method and application of formaldehyde-free glue for artificial boards. The adhesive prepared by the method of the present invention does not contain aldehyde groups, and the artificial boards using this adhesive can achieve the effect of zero formaldehyde release; the above-mentioned formaldehyde-free glue introduces functional monomers during the preparation process, so that the formaldehyde-free glue has certain antibacterial and flame retardant effects; in addition, a three-stage polymerization method is adopted in the preparation of the formaldehyde-free glue to control extremely low monomer residues, so that the formaldehyde-free glue has no odor, and is an environmentally friendly adhesive with excellent comprehensive performance.
为实现上述目的，本发明的具体技术方案如下：To achieve the above purpose, the specific technical solutions of the present invention are as follows:
一种人造板无醛胶的制备方法，包括以下步骤：A method for preparing formaldehyde-free adhesive for artificial boards comprises the following steps:
（1）将主单体、第一引发剂、乳化剂以及溶剂混合，于20-40℃反应0.5-1h；所述主单体选自乙烯、氯乙烯、醋酸乙烯、偏二氯乙烯中的两种或两种以上；(1) Mixing a main monomer, a first initiator, an emulsifier and a solvent, and reacting them at 20-40° C. for 0.5-1 h; the main monomer is selected from two or more of ethylene, vinyl chloride, vinyl acetate and vinylidene chloride;
（2）将功能单体和第二引发剂加入步骤（1）中的反应体系，于40-75℃继续反应2-6h；所述功能单体包括但不限于：含双键和羟基的化合物、含双键和羧基的化合物、含双键和环氧基团的化合物、含双键硅氧烷的化合物、乙烯基异丁基醚、异丁氧基甲基丙烯酰胺、双丙酮丙烯酰胺中的一种或几种；(2) adding a functional monomer and a second initiator to the reaction system in step (1), and continuing the reaction at 40-75° C. for 2-6 hours; the functional monomer includes but is not limited to: one or more of a compound containing a double bond and a hydroxyl group, a compound containing a double bond and a carboxyl group, a compound containing a double bond and an epoxy group, a compound containing a double bond siloxane, vinyl isobutyl ether, isobutoxymethyl acrylamide, and diacetone acrylamide;
（3）将步骤（2）中的反应体系于40-60℃反应0.5-1h，加入终止剂，得到聚合乳液，将聚合乳液用于制备无醛胶。(3) The reaction system in step (2) is reacted at 40-60° C. for 0.5-1 h, a terminator is added to obtain a polymer emulsion, and the polymer emulsion is used to prepare a formaldehyde-free adhesive.
优选地，所述含双键和羟基的化合物含有以下结构：Preferably, the compound containing a double bond and a hydroxyl group has the following structure:
； ;
其中，R为含酸酐基、羧基、氨基、亚氨基、酰胺基、烷氧硅烷基、硅烷醇基、甲硅烷醚基、羟基、环氧基、卤素、巯基、环硫化物基、不饱和键官能团的烷基。Among them, R is an alkyl group containing an acid anhydride group, a carboxyl group, an amino group, an imino group, an amide group, an alkoxysilyl group, a silanol group, a silyl ether group, a hydroxyl group, an epoxy group, a halogen group, a mercapto group, an episulfide group, or an unsaturated bond functional group.
优选地，所述含双键和羧基的化合物含有以下结构：Preferably, the compound containing a double bond and a carboxyl group has the following structure:
； ;
其中，R为含酸酐基、羧基、氨基、亚氨基、烷氧硅烷基、硅烷醇基、甲硅烷醚基、羟基、环氧基、卤素、巯基、环硫化物基、不饱和键官能团的烷基。Among them, R is an acid anhydride group, a carboxyl group, an amino group, an imino group, an alkoxysilyl group, a silanol group, a silyl ether group, a hydroxyl group, an epoxy group, a halogen group, a mercapto group, an episulfide group, and an alkyl group containing an unsaturated bond functional group.
优选地，所述含双键和环氧基团的化合物含有以下结构：Preferably, the compound containing a double bond and an epoxy group has the following structure:
； ;
其中，R为含酸酐基、羧基、氨基、亚氨基、烷氧硅烷基、硅烷醇基、甲硅烷醚基、羟基、环氧基、卤素、巯基、环硫化物基、不饱和键官能团的烷基。Among them, R is an acid anhydride group, a carboxyl group, an amino group, an imino group, an alkoxysilyl group, a silanol group, a silyl ether group, a hydroxyl group, an epoxy group, a halogen group, a mercapto group, an episulfide group, and an alkyl group containing an unsaturated bond functional group.
优选地，所述含双键硅氧烷的化合物含有以下结构：Preferably, the double bond siloxane-containing compound has the following structure:
； ;
其中，R1、R2、R3分别为含酸酐基、羧基、氨基、亚氨基、烷氧硅烷基、硅烷醇基、甲硅烷醚基、羟基、环氧基、卤素、巯基、环硫化物基、不饱和键官能团的烷基。R1 , R2 , and R3 are respectively an acid anhydride group, a carboxyl group, an amino group, an imino group, an alkoxysilyl group, a silanol group, a silyl ether group, a hydroxyl group, an epoxy group, a halogen group, a mercapto group, an episulfide group, and an alkyl group containing an unsaturated bond functional group.
优选地，所述主单体、功能单体的质量比为1:（0.05-0.5）。Preferably, the mass ratio of the main monomer to the functional monomer is 1:(0.05-0.5).
优选地，所述聚合乳液与固化交联剂混合均匀制备无醛胶。Preferably, the polymer emulsion and the curing cross-linking agent are uniformly mixed to prepare the formaldehyde-free adhesive.
优选地，所述固化交联剂是由：含异氰酸根的异氰酸酯、已二酸二酰肼、三聚氰胺、三羟甲基三聚氰胺、六甲氧基甲基三聚氰胺、多元醇化合物、有机胺化合物、含双键的有机硅化合物、羟丙基甲基纤维素、过氧化物化合物中的一种或几种复合组成。Preferably, the curing cross-linking agent is composed of one or more of the following: isocyanate containing isocyanate, adipic acid dihydrazide, melamine, trimethylol melamine, hexamethoxymethyl melamine, polyol compounds, organic amine compounds, organosilicon compounds containing double bonds, hydroxypropyl methylcellulose, and peroxide compounds.
进一步优选地，所述多元醇化合物包括乙二醇、丙二醇、丁二醇、戊二醇中的一种。More preferably, the polyol compound includes one of ethylene glycol, propylene glycol, butylene glycol and pentanediol.
进一步优选地，所述有机胺化合物包括邻苯二胺、间苯二胺、对苯二胺、邻氯苯胺、间氯苯胺、对氯苯胺、N,N-二甲基乙醇胺、N,N-二乙基乙醇胺、三亚乙基二胺、二亚乙基三胺、环乙烯亚胺、聚乙烯亚胺中的一种。Further preferably, the organic amine compound includes one of o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, o-chloroaniline, m-chloroaniline, p-chloroaniline, N,N-dimethylethanolamine, N,N-diethylethanolamine, triethylenediamine, diethylenetriamine, cyclohexyleneimine and polyethyleneimine.
进一步优选地，所述含双键的有机硅化合物包括乙烯基三氯硅烷、乙烯基三甲氧基硅烷、乙烯基三乙氧基硅烷、苯乙烯基三甲氧基硅烷、3-丙烯酰氧丙基三甲氧基硅烷、3-甲基丙烯酰氧丙基三甲氧基硅烷、3-甲基丙烯酰氧丙基三乙氧基硅烷、3-甲基丙烯酰氧丙基甲基二乙氧基硅烷、3-甲基丙烯酰氧丙基甲基二甲氧基硅烷、环氧丙氧基丙乙烯基三甲氧基硅烷、3-丙烯酰氧丙基三甲氧基硅烷中的一种。Further preferably, the double bond-containing organosilicon compound includes one of vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, styryltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, glycidoxypropylvinyltrimethoxysilane, and 3-acryloxypropyltrimethoxysilane.
优选地，所述第一引发剂和第二引发剂为偶氮类引发剂和/或过氧化物引发剂。Preferably, the first initiator and the second initiator are azo initiators and/or peroxide initiators.
优选地，所述第一引发剂和第二引发剂的用量为总单体量的0.1%-0.6%。Preferably, the first initiator and the second initiator are used in an amount of 0.1% to 0.6% of the total monomer amount.
所述总单体量为主单体和功能单体质量的总和。The total monomer amount is the sum of the masses of the main monomer and the functional monomer.
优选地，所述乳化剂为阴离子型乳化剂和/或非离子型乳化剂。Preferably, the emulsifier is an anionic emulsifier and/or a nonionic emulsifier.
优选地，所述乳化剂的用量为总单体量的1%-8%。Preferably, the amount of the emulsifier used is 1%-8% of the total monomer amount.
优选地，所述终止剂为山梨酸。Preferably, the terminator is sorbic acid.
优选地，所述终止剂的用量为总单体量的0.01%-0.03%。Preferably, the amount of the terminator is 0.01%-0.03% of the total monomer amount.
本发明还提供一种上述无醛胶在人造板中的应用。The present invention also provides an application of the formaldehyde-free adhesive in artificial boards.
本发明方法制备得到的聚合乳液的重量平均分子量为1000～500000道尔顿，粘度为500～20000 mPa·s，玻璃化转变温度（Tg）为-50～70℃，乳液固含量控制在20~65%。本发明采用三阶段聚合反应制备得到烯基聚合乳液，使得聚合乳液具备优异的性能，且聚合乳液的残留单体的含量低达5-100 PPM，控制极低的单体残留，使得本发明制备的无醛胶无异味；通过引入功能单体来进一步改善聚合乳液的性质，使其更适合作为木材胶粘剂；其中，采用不同的单体组合以及不同的比例可以获得不同性质的乳液。本发明采用乳液聚合反应制备聚合乳液，工艺简单而成熟，聚合条件容易控制；引入的功能单体可以调节胶粘剂的性能，得到符合设计要求的胶粘剂；本发明的固化交联剂选择具有可反应基团的化合物，可以实现自交联和/或分子间交联，从而达到干燥固化的目的；聚合乳液和固化交联剂之间的比例不同可以实现不同的固化速度，因而可以通过改变固化交联剂和乳液的比例来控制固化速度，使得胶粘剂符合现场生产的要求。本发明通过聚合乳液与固化交联剂进行复配的方式，将其应用到人造板上，可以获得性能优异的板材。The weight average molecular weight of the polymer emulsion prepared by the method of the present invention is 1000-500000 Dalton, the viscosity is 500-20000 mPa·s, the glass transition temperature (Tg) is -50-70°C, and the solid content of the emulsion is controlled at 20-65%. The present invention adopts a three-stage polymerization reaction to prepare the olefin polymer emulsion, so that the polymer emulsion has excellent performance, and the content of the residual monomer of the polymer emulsion is as low as 5-100 PPM, and the extremely low monomer residue is controlled, so that the formaldehyde-free glue prepared by the present invention has no odor; the properties of the polymer emulsion are further improved by introducing functional monomers, making it more suitable as a wood adhesive; wherein, different monomer combinations and different proportions can be used to obtain emulsions with different properties. The present invention adopts emulsion polymerization to prepare polymer emulsion, the process is simple and mature, and the polymerization conditions are easy to control; the introduced functional monomer can adjust the performance of the adhesive to obtain an adhesive that meets the design requirements; the curing cross-linking agent of the present invention selects a compound with a reactive group, which can achieve self-crosslinking and/or intermolecular crosslinking, thereby achieving the purpose of drying and curing; different ratios between the polymer emulsion and the curing cross-linking agent can achieve different curing speeds, so the curing speed can be controlled by changing the ratio of the curing cross-linking agent to the emulsion, so that the adhesive meets the requirements of on-site production. The present invention uses the polymer emulsion and the curing cross-linking agent to compound and apply them to the artificial board to obtain a board with excellent performance.
与现有技术相比，本发明的有益之处在于：Compared with the prior art, the present invention is beneficial in that:
（1）本发明方法制备得到的无醛胶不含甲醛，具有极低的残单含量以及具有生物可降解性，对环境友好，可以广泛使用；(1) The formaldehyde-free adhesive prepared by the method of the present invention does not contain formaldehyde, has an extremely low residual content and is biodegradable, is environmentally friendly, and can be widely used;
（2）本发明提供的方法在主单体先低温反应0.5-1h之后，再引入功能单体升温反应2-6h，然后降温继续反应0.5-1h，制备得到聚合乳液，相比于容易被细菌和霉菌侵蚀淀粉胶和蛋白胶，本发明制备得到的聚合乳液具有一定的抗菌性和阻燃性；(2) The method provided by the present invention is to first react the main monomer at low temperature for 0.5-1h, then introduce the functional monomer to react at a high temperature for 2-6h, and then cool down and continue to react for 0.5-1h to prepare a polymer emulsion. Compared with starch glue and protein glue that are easily corroded by bacteria and mold, the polymer emulsion prepared by the present invention has certain antibacterial and flame retardancy;
（3）与现存的无醛MDI（二苯基甲烷二异氰酸酯）刚性胶相比，本发明的无醛胶可以通过调整单体组合以及固化交联剂的加入比例来改变胶粘剂的性质和固化时间，使得板材具有良好的柔韧性和可弯曲性，避免了板材在加工的过程中容易爆边碎裂的问题；(3) Compared with the existing formaldehyde-free MDI (diphenylmethane diisocyanate) rigid adhesive, the formaldehyde-free adhesive of the present invention can change the properties and curing time of the adhesive by adjusting the monomer combination and the addition ratio of the curing cross-linking agent, so that the board has good flexibility and bendability, avoiding the problem of the board being prone to cracking during processing;
（4）本发明方法提供的无醛胶在提高板材可加工性的同时还具有成本低的优势，具有广阔的应用前景。(4) The formaldehyde-free adhesive provided by the method of the present invention has the advantage of low cost while improving the machinability of the board, and has broad application prospects.
具体实施方式DETAILED DESCRIPTION
以下结合实施例对本发明技术方案进行清楚、完整的描述，基于本发明的实施例，本领域普通技术人员在没有做出创造性劳动的前提下所得到的所有其它实施例，都属于本发明所保护的范围。本领域技术人员依据以下实施方式所作的任何等效变换或替代，均属于本发明的保护范围之内。The following is a clear and complete description of the technical solution of the present invention in combination with the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention. Any equivalent transformation or substitution made by those skilled in the art based on the following implementation methods belongs to the protection scope of the present invention.
本发明提供一种人造板无醛胶的制备方法，包括以下步骤：The present invention provides a method for preparing formaldehyde-free adhesive for artificial boards, comprising the following steps:
（1）将主单体、第一引发剂、乳化剂以及溶剂混合，于20-40℃反应0.5-1h；所述主单体选自乙烯、氯乙烯、醋酸乙烯、偏二氯乙烯中的两种或两种以上；(1) Mixing a main monomer, a first initiator, an emulsifier and a solvent, and reacting them at 20-40° C. for 0.5-1 h; the main monomer is selected from two or more of ethylene, vinyl chloride, vinyl acetate and vinylidene chloride;
（2）将功能单体和第二引发剂加入步骤（1）中的反应体系，于40-75℃继续反应2-6h；所述功能单体包括但不限于：含双键和羟基的化合物、含双键和羧基的化合物、含双键和环氧基团的化合物、含双键硅氧烷的化合物、乙烯基异丁基醚、异丁氧基甲基丙烯酰胺、双丙酮丙烯酰胺中的一种或几种；(2) adding a functional monomer and a second initiator to the reaction system in step (1), and continuing the reaction at 40-75° C. for 2-6 hours; the functional monomer includes but is not limited to: one or more of a compound containing a double bond and a hydroxyl group, a compound containing a double bond and a carboxyl group, a compound containing a double bond and an epoxy group, a compound containing a double bond siloxane, vinyl isobutyl ether, isobutoxymethyl acrylamide, and diacetone acrylamide;
（3）将步骤（2）中的反应体系于40-60℃反应0.5-1h，加入终止剂，得到聚合乳液，将聚合乳液用于制备无醛胶。(3) The reaction system in step (2) is reacted at 40-60° C. for 0.5-1 h, a terminator is added to obtain a polymer emulsion, and the polymer emulsion is used to prepare a formaldehyde-free adhesive.
在一些示例中，所述聚合乳液与固化交联剂混合均匀得到无醛胶。In some examples, the polymer emulsion and the curing cross-linking agent are uniformly mixed to obtain a formaldehyde-free adhesive.
在一些示例中，所述第一引发剂和第二引发剂为偶氮类引发剂和/或过氧化物引发剂。In some examples, the first initiator and the second initiator are azo initiators and/or peroxide initiators.
在一些示例中，所述第一引发剂和第二引发剂的用量为总单体量的0.1%-0.6%。In some examples, the first initiator and the second initiator are used in an amount of 0.1% to 0.6% of the total monomer amount.
在一些示例中，所述乳化剂为阴离子型乳化剂和/或非离子型乳化剂。In some examples, the emulsifier is an anionic emulsifier and/or a nonionic emulsifier.
在一些示例中，所述乳化剂的用量为总单体量的1%-8%。In some examples, the amount of the emulsifier used is 1%-8% of the total monomer amount.
在一些示例中，所述终止剂的用量为总单体量的0.01%-0.03%。In some examples, the amount of the terminator is 0.01%-0.03% of the total monomer amount.
在下述实施例中，如无特别说明，所用终止剂为山梨酸；所用固化交联剂为二苯基甲烷二异氰酸酯；聚合乳液的粘度采用BROOKFIELD粘度计在室温下测得，玻璃化转变温度由DSC测得，固含量按GB/T 27573-2011测定。In the following examples, unless otherwise specified, the terminator used is sorbic acid; the curing crosslinking agent used is diphenylmethane diisocyanate; the viscosity of the polymer emulsion is measured using a BROOKFIELD viscometer at room temperature, the glass transition temperature is measured by DSC, and the solid content is measured according to GB/T 27573-2011.
实施例1Example 1
本实施例提供一种无醛胶的制备方法，步骤如下：This embodiment provides a method for preparing formaldehyde-free glue, and the steps are as follows:
（1）将250g乙烯和700g醋酸乙烯加入2000g水中，搅拌过程中加入3g过硫酸钾、10g硬脂酸钠和30g OP-10乳化剂，于30℃反应0.5h；(1) Add 250g ethylene and 700g vinyl acetate into 2000g water, add 3g potassium persulfate, 10g sodium stearate and 30g OP-10 emulsifier during stirring, and react at 30℃ for 0.5h;
（2）将50g乙烯基异丁基醚和3g偶氮二异丁基脒盐酸盐加入步骤（1）中的反应体系，于65℃继续反应6h；(2) Add 50 g of vinyl isobutyl ether and 3 g of azobisisobutylamidine hydrochloride to the reaction system in step (1), and continue the reaction at 65° C. for 6 h;
（3）将步骤（2）中的反应体系于45℃反应1h，加入0.2g山梨酸，得到固含量52%，粘度为2000 mPa·s，Tg=5℃，残单含量为20的聚合乳液；(3) The reaction system in step (2) was reacted at 45°C for 1 hour, and 0.2 g of sorbic acid was added to obtain a polymer emulsion having a solid content of 52%, a viscosity of 2000 mPa·s, a Tg of 5°C, and a residual monomer content of 20;
（4）将聚合乳液与固化交联剂混合均匀，得到无醛胶。(4) Mix the polymer emulsion and the curing cross-linking agent evenly to obtain formaldehyde-free glue.
实施例2Example 2
本实施例提供一种无醛胶的制备方法，步骤如下：This embodiment provides a method for preparing formaldehyde-free glue, and the steps are as follows:
（1）将200g乙烯、600g醋酸乙烯和120g氯乙烯加入2000g水中，搅拌过程中加入3g过硫酸钾、10g硬脂酸钠和30g OP-10乳化剂，于35℃反应1h；(1) Add 200g ethylene, 600g vinyl acetate and 120g vinyl chloride into 2000g water, add 3g potassium persulfate, 10g sodium stearate and 30g OP-10 emulsifier during stirring, and react at 35℃ for 1h;
（2）将80g 4-羟基丁基丙烯酸酸酯和3g偶氮二异丁基脒盐酸盐加入步骤（1）中的反应体系，于60℃继续反应5h；(2) adding 80 g of 4-hydroxybutyl acrylate and 3 g of azobisisobutylamidine hydrochloride to the reaction system in step (1), and continuing the reaction at 60° C. for 5 h;
（3）将步骤（2）中的反应体系于50℃反应0.5h，加入0.2g山梨酸，得到固含量53%，粘度为600 mPa·s，Tg=12℃，残单含量为10的聚合乳液；(3) The reaction system in step (2) was reacted at 50° C. for 0.5 h, and 0.2 g of sorbic acid was added to obtain a polymer emulsion having a solid content of 53%, a viscosity of 600 mPa·s, Tg=12° C., and a residual monomer content of 10;
（4）将聚合乳液与固化交联剂混合均匀，得到无醛胶。(4) Mix the polymer emulsion and the curing cross-linking agent evenly to obtain formaldehyde-free glue.
实施例3Example 3
本实施例提供一种无醛胶的制备方法，步骤如下：This embodiment provides a method for preparing formaldehyde-free glue, and the steps are as follows:
（1）将200g乙烯和700g醋酸乙烯加入2000g水中，搅拌过程中加入3g过硫酸钾、10g硬脂酸钠和30g OP-10乳化剂，于40℃反应0.5h；(1) Add 200g ethylene and 700g vinyl acetate into 2000g water, add 3g potassium persulfate, 10g sodium stearate and 30g OP-10 emulsifier during stirring, and react at 40℃ for 0.5h;
（2）将100g N-羟甲基丙烯酰胺和3g偶氮二异丁基脒盐酸盐加入步骤（1）中的反应体系，于70℃继续反应3h；(2) adding 100 g of N-hydroxymethyl acrylamide and 3 g of azobisisobutylamidine hydrochloride to the reaction system in step (1), and continuing the reaction at 70° C. for 3 h;
（3）将步骤（2）中的反应体系于40℃反应1h，加入0.2g山梨酸，得到固含量54%，粘度为3500 mPa·s，Tg=5℃，残单含量为10的聚合乳液；(3) The reaction system in step (2) was reacted at 40°C for 1 hour, and 0.2 g of sorbic acid was added to obtain a polymer emulsion having a solid content of 54%, a viscosity of 3500 mPa·s, Tg=5°C, and a residual monomer content of 10;
（4）将聚合乳液与固化交联剂混合均匀，得到无醛胶。(4) Mix the polymer emulsion and the curing cross-linking agent evenly to obtain formaldehyde-free glue.
对比例1Comparative Example 1
本对比例无醛胶的制备方法，步骤如下：The preparation method of the formaldehyde-free glue in this comparative example comprises the following steps:
（1）将280g乙烯、700g醋酸乙烯、20g乙烯基异丁基醚加入2000g水中，搅拌过程中加入3g过硫酸钾、3g偶氮二异丁基脒盐酸盐、10g硬脂酸钠和30g OP-10乳化剂，于65℃反应7.5h，加入0.2g山梨酸，得到固含量52%，粘度为2300 mPa·s，Tg=8℃，残单含量为1500的聚合乳液；(1) 280 g of ethylene, 700 g of vinyl acetate, and 20 g of vinyl isobutyl ether were added to 2000 g of water, and 3 g of potassium persulfate, 3 g of azobisisobutylamidine hydrochloride, 10 g of sodium stearate, and 30 g of OP-10 emulsifier were added during stirring. The mixture was reacted at 65°C for 7.5 h, and 0.2 g of sorbic acid was added to obtain a polymer emulsion having a solid content of 52%, a viscosity of 2300 mPa·s, Tg=8°C, and a residual monomer content of 1500.
（2）将聚合乳液与固化交联剂混合均匀，得到无醛胶。(2) Mix the polymer emulsion and the curing cross-linking agent evenly to obtain formaldehyde-free glue.
对比例2Comparative Example 2
本对比例无醛胶的制备方法，步骤如下：The preparation method of the formaldehyde-free glue in this comparative example comprises the following steps:
（1）将280g乙烯、700g醋酸乙烯、20g乙烯基异丁基醚加入2000g水中，搅拌过程中加入3g过硫酸钾、3g偶氮二异丁基脒盐酸盐、10g硬脂酸钠和30g OP-10乳化剂，于65℃反应6.5h；(1) Add 280g ethylene, 700g vinyl acetate, and 20g vinyl isobutyl ether to 2000g water, add 3g potassium persulfate, 3g azobisisobutylamidine hydrochloride, 10g sodium stearate, and 30g OP-10 emulsifier during stirring, and react at 65°C for 6.5h;
（2）将上述反应体系于40℃继续反应1h，加入0.2g山梨酸，得到固含量52%，粘度为2800 mPa·s，Tg=9℃，残单含量为1200的聚合乳液；(2) The above reaction system was continued to react at 40°C for 1 hour, and 0.2 g of sorbic acid was added to obtain a polymer emulsion with a solid content of 52%, a viscosity of 2800 mPa·s, Tg = 9°C, and a residual monomer content of 1200;
（3）将聚合乳液与固化交联剂混合均匀，得到无醛胶。(3) Evenly mix the polymer emulsion and the curing cross-linking agent to obtain formaldehyde-free adhesive.
对比例3Comparative Example 3
本对比例无醛胶的制备方法，步骤如下：The preparation method of the formaldehyde-free glue in this comparative example comprises the following steps:
（1）将280g乙烯和700g醋酸乙烯加入2000g水中，搅拌过程中加入3g过硫酸钾、10g硬脂酸钠和30g OP-10乳化剂，于65℃反应0.5h；(1) Add 280g ethylene and 700g vinyl acetate into 2000g water, add 3g potassium persulfate, 10g sodium stearate and 30g OP-10 emulsifier during stirring, and react at 65℃ for 0.5h;
（2）将20g乙烯基异丁基醚和3g偶氮二异丁基脒盐酸盐加入步骤（1）中的反应体系，于65℃继续反应6h；(2) adding 20 g of vinyl isobutyl ether and 3 g of azobisisobutylamidine hydrochloride to the reaction system in step (1), and continuing the reaction at 65° C. for 6 h;
（3）将步骤（2）中的反应体系于65℃反应1h，加入0.2g山梨酸，得到固含量52%，粘度为2000 mPa·s，Tg=8℃，残单含量为300的聚合乳液；(3) The reaction system in step (2) was reacted at 65°C for 1 h, and 0.2 g of sorbic acid was added to obtain a polymer emulsion having a solid content of 52%, a viscosity of 2000 mPa·s, a Tg of 8°C, and a residual monomer content of 300;
（4）将聚合乳液与固化交联剂混合均匀，得到无醛胶。(4) Evenly mix the polymer emulsion and the curing cross-linking agent to obtain formaldehyde-free adhesive.
将实施例1-3和对比例1-3的聚合乳液和无醛胶于110℃下制成膜（25mm*25mm*1mm），测试膜的拉伸强度和断裂伸长率。测试结果见表1。The polymer emulsions of Examples 1-3 and Comparative Examples 1-3 and the formaldehyde-free adhesive were made into films (25 mm*25 mm*1 mm) at 110° C., and the tensile strength and elongation at break of the films were tested. The test results are shown in Table 1.
表1：实施例1-3和对比例1-3的聚合乳液和无醛胶的膜性能Table 1: Film properties of polymer emulsions and formaldehyde-free adhesives of Examples 1-3 and Comparative Examples 1-3
应用例1Application Example 1
本应用例为实施例1制备得到的无醛胶在P2刨花板中的应用，步骤如下：This application example is the application of the formaldehyde-free glue prepared in Example 1 in P2 particleboard, and the steps are as follows:
S1. 将38g聚合乳液和5g固化交联剂混合均匀后，与1080g表层细木屑克充分搅拌均匀，备用；S1 38g of polymer emulsion and 5g of curing crosslinking agent mixed, and 1080g of surface fine sawdust grams fully stirred and set aside;
S2. 将84g聚合乳液和10g固化交联剂混合均匀后，与1616g芯层粗木屑克充分搅拌均匀，备用；S2 84g of polymer emulsion and 10g of curing cross-linking agent were mixed, and 1616g of core coarse sawdust grams fully stirred and set aside;
S3. 采用江苏无锡阳明橡胶机械有限公司生产的立式自动油压成型机将以上混胶后的木屑按比例压成幅面为520*520*18mm的板材，养护72h。S3. Use the vertical automatic hydraulic molding machine produced by Jiangsu Wuxi Yangming Rubber Machinery Co., Ltd. to press the mixed wood chips into boards with a width of 520*520*18mm according to proportion, and maintain for 72 hours.
应用例2Application Example 2
本应用例为实施例2制备得到的无醛胶在P6刨花板中的应用，步骤如下：This application example is the application of the formaldehyde-free glue prepared in Example 2 in P6 particleboard, and the steps are as follows:
S1. 将76g聚合乳液和7g固化交联剂混合均匀后，与1080g表层细木屑克充分搅拌均匀，备用；S1. After 76g of the polymer emulsion and 7g of curing crosslinking agent are mixed, 1080g of surface fine sawdust grams are fully stirred and set aside;
S2. 将129g聚合乳液和10g固化交联剂混合均匀后，与1616g芯层粗木屑克充分搅拌均匀，备用；S2 129g of the polymer emulsion and 10g of curing cross-linking agent were mixed, and 1616g of core coarse sawdust grams were fully stirred and set aside;
S3. 采用江苏无锡阳明橡胶机械有限公司生产的立式自动油压成型机将以上混胶后的木屑按比例压成幅面为520*520*18mm的板材，养护72h。S3. Use the vertical automatic hydraulic molding machine produced by Jiangsu Wuxi Yangming Rubber Machinery Co., Ltd. to press the mixed wood chips into boards with a width of 520*520*18mm according to proportion, and maintain for 72 hours.
应用例3Application Example 3
本应用例为实施例3制备得到的无醛胶在P10刨花板中的应用，步骤如下：This application example is the application of the formaldehyde-free glue prepared in Example 3 in P10 particle board, and the steps are as follows:
S1. 将216g聚合乳液和21g固化交联剂混合均匀后，与1080g表层细木屑克充分搅拌均匀，备用；S1 216g of polymer emulsion and 21g of curing crosslinking agent mixed, and 1080g of surface fine sawdust grams fully stirred and set aside;
S2. 将281g聚合乳液和14g固化交联剂混合均匀后，与1616g芯层粗木屑克充分搅拌均匀，备用；S2 281g of polymer emulsion and 14g of curing cross-linking agent were mixed, and 1616g of core layer of coarse sawdust grams were fully stirred and set aside;
S3. 采用江苏无锡阳明橡胶机械有限公司生产的立式自动油压成型机将以上混胶后的木屑按比例压成幅面为520*520*18mm的板材，养护72h。S3. Use the vertical automatic hydraulic molding machine produced by Jiangsu Wuxi Yangming Rubber Machinery Co., Ltd. to press the mixed wood chips into boards with a width of 520*520*18mm according to proportion, and maintain for 72 hours.
应用例4Application Example 4
本应用例为实施例1制备得到的无醛胶在胶合板中的应用，步骤如下：This application example is the application of the formaldehyde-free glue prepared in Example 1 in plywood, and the steps are as follows:
将聚合乳液40g和固化交联剂4g固化交联剂充分搅拌均匀后备用。Stir 40 g of the polymer emulsion and 4 g of the curing cross-linking agent thoroughly and evenly for later use.
在两块木片（25×80mm）上，一端画标线（15×25mm），然后在标线区域涂胶（施胶量150g/m2），施胶后两块木片使用木工夹进行压合，放入温度20℃、相对湿度60%的标准养护室，养护7天。On two wood chips (25×80mm), draw a marking line (15×25mm) at one end, then apply glue (150g/m2 ) on the marking area. After gluing, press the two wood chips together with woodworking clamps and put them in a standard curing room with a temperature of 20℃ and a relative humidity of 60% for 7 days.
应用例5Application Example 5
本应用例为实施例2制备得到的无醛胶在胶合板中的应用，其步骤与应用例4基本相同。This application example is the application of the formaldehyde-free glue prepared in Example 2 in plywood, and its steps are basically the same as those of Application Example 4.
应用例6Application Example 6
本应用例为实施例3制备得到的无醛胶在胶合板中的应用，其步骤与应用例4基本相同。This application example is the application of the formaldehyde-free glue prepared in Example 3 in plywood, and its steps are basically the same as those in Application Example 4.
对比应用例1Comparative application example 1
本对比应用例的无醛胶在P2刨花板中的应用，应用步骤与应用例1基本相同，不同之处在于，本对比应用例用的聚合乳液为对比例1制备得到的聚合乳液。The application steps of the formaldehyde-free glue in this comparative application example in P2 particle board are basically the same as those in Application Example 1, except that the polymer emulsion used in this comparative application example is the polymer emulsion prepared in Comparative Example 1.
应用例1-3和对比应用例1中同样的配方压三块板，按照GB/T 4897—2015《刨花板》测量各种性能，每一块分成三个样本供测试9次，去掉最好和最差的数值，取余下7次数值的平均值。结果如表2。应用例4-6的胶合板，按照《EN204-非结构用热塑性木材粘合剂的分类》中D4标准检测各项性能，结果如表3。Three boards were pressed with the same formula as in Application Examples 1-3 and Comparative Application Example 1, and various properties were measured according to GB/T 4897-2015 "Particleboard". Each board was divided into three samples for 9 tests, and the best and worst values were removed, and the average of the remaining 7 values was taken. The results are shown in Table 2. The plywood of Application Examples 4-6 was tested for various properties according to the D4 standard in "EN204-Classification of Thermoplastic Wood Adhesives for Non-Structural Use", and the results are shown in Table 3.
表2：应用例1-3和对比应用例1的刨花板性能结果Table 2: Particleboard performance results of application examples 1-3 and comparative application example 1
表3：应用例4-6胶合板的性能结果Table 3: Performance results of plywood in application examples 4-6
尽管已经示出和描述了本发明的实施例，对于本领域的普通技术人员而言，可以理解在不脱离本发明的原理和精神的情况下可以对这些实施例进行多种变化、修改、替换和变型，本发明的范围由所附权利要求及其等同物限定。Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
| Application Number | Priority Date | Filing Date | Title |
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| CN202410992507.3ACN118599448B (en) | 2024-07-23 | 2024-07-23 | Preparation method and application of formaldehyde-free adhesive for artificial boards |
| Application Number | Priority Date | Filing Date | Title |
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| CN202410992507.3ACN118599448B (en) | 2024-07-23 | 2024-07-23 | Preparation method and application of formaldehyde-free adhesive for artificial boards |
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| CN118599448Atrue CN118599448A (en) | 2024-09-06 |
| CN118599448B CN118599448B (en) | 2025-01-28 |
| Application Number | Title | Priority Date | Filing Date |
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| CN202410992507.3AActiveCN118599448B (en) | 2024-07-23 | 2024-07-23 | Preparation method and application of formaldehyde-free adhesive for artificial boards |
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| US20180142118A1 (en)* | 2016-11-22 | 2018-05-24 | Nan Ya Plastics Corporation | Low-voc-emission waterborne coating having high hardness and good adhesion and process for producing the same |
| CN114213999A (en)* | 2021-12-13 | 2022-03-22 | 云南正邦科技有限公司 | Water-based formaldehyde-free adhesive |
| CN114231223A (en)* | 2021-12-13 | 2022-03-25 | 云南正邦科技有限公司 | Water-based formaldehyde-free adhesive and preparation method thereof |
| WO2023006016A1 (en)* | 2021-07-29 | 2023-02-02 | 江苏凯伦建材股份有限公司 | Amine-free elastic acrylate emulsion, waterproof coating, and preparation method |
| CN115838576A (en)* | 2022-12-14 | 2023-03-24 | 云南正邦科技有限公司 | Aldehyde-free adhesive and application thereof in preparation of P2-P12-grade shaving boards |
| US20230279171A1 (en)* | 2020-07-07 | 2023-09-07 | Synthomer Sdn. Bhd. | Polymer latex |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20180142118A1 (en)* | 2016-11-22 | 2018-05-24 | Nan Ya Plastics Corporation | Low-voc-emission waterborne coating having high hardness and good adhesion and process for producing the same |
| US20230279171A1 (en)* | 2020-07-07 | 2023-09-07 | Synthomer Sdn. Bhd. | Polymer latex |
| WO2023006016A1 (en)* | 2021-07-29 | 2023-02-02 | 江苏凯伦建材股份有限公司 | Amine-free elastic acrylate emulsion, waterproof coating, and preparation method |
| CN114213999A (en)* | 2021-12-13 | 2022-03-22 | 云南正邦科技有限公司 | Water-based formaldehyde-free adhesive |
| CN114231223A (en)* | 2021-12-13 | 2022-03-25 | 云南正邦科技有限公司 | Water-based formaldehyde-free adhesive and preparation method thereof |
| CN115838576A (en)* | 2022-12-14 | 2023-03-24 | 云南正邦科技有限公司 | Aldehyde-free adhesive and application thereof in preparation of P2-P12-grade shaving boards |
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| CN118599448B (en) | 2025-01-28 |
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