小粒径聚丙烯酸酯乳液的合成及助成膜性能

Synthesis and Assistant-Film-Forming Performance of Polyacrylate Emulsion

采用种子半连续乳液聚合法合成了小粒径聚丙烯酸酯乳液(PA),取代有机小分子成膜助剂辅助硬树脂乳液成膜,制备超低挥发性有机化合物(VOC)含量的水性木器涂料。考察了PA玻璃化转变温度(Tg)、乳化剂配比及添加量和甲基丙烯酸(MAA)用量等对乳液聚合稳定性、乳液性能及助成膜性能的影响。结果表明,聚合物Tg由0℃降到-20℃时,PA助成膜能力明显增强;复合乳化剂中随反应性乳化剂比例的增大,凝胶率从0.83%降低到0.10%;乳化剂的用量增加到2.1%时,乳液平均粒径可减小到69 nm,助成膜能力增强;MAA添加量为4.5%时制备的PA配制的水性木器涂料的总VOC含量低至33 g/L。

The polyacrylate emulsion （PA） with small particle size was synthesized by seeded semi- continuous emulsion polymerization, and was used as a coalescent of the hard resin latex to replace small organic molecules to prepare waterborne wood coatings containing ultra-low volatile organic compound（ VOC ） contents. The effects of Ts of PA, proportions and dosages of emulsifiers, and amounts of MAA on emulsion polymerization stability, emulsion properties, and assistant-film-forming performance of PA were studied. It was found that the assistant-film-forming ability of PA was significantly increased with decreasing of polymer Tg from 0 ℃ to - 20 ℃ ; and the gel content of PA was reduced from 0. 83% to 0. 10% with increasing of the reactive emulsifier contents;the PA average particle size could be reduced to 69 nm with increasing of emulsifier dosage up to 2. 1% and the assistant-film-forming ability of PA was enhanced as well ; the total VOC content of the waterborne wood coatings formulated by PA with 4. 5% MAA dosage was as low as 33 g/l,