氟代丙烯酸酯三元共聚物细乳液的合成与表征

Synthesis of Fluorinated Acrylate Ternary Copolymer Latex by Miniemulsion Polymerization and Characterization

在低乳化剂用量和不加助乳化剂的条件下 ,采用细乳液聚合方法 ,合成了平均粒径在 1 1 0～ 1 5 0 nm的氟代丙烯酸酯 (FA)、甲基丙烯酸甲酯 (MMA)及甲基丙烯酸丁酯 (BMA)三元共聚物乳液 .利用 GPC,FTIR及 1 H NMR谱表征了共聚物分子量和结构组成 ,采用激光光散射法研究了聚合过程中粒径变化规律 ,通过接触角方法对共聚物表面性能进行了表征 .结果表明 ,油溶性引发剂 AIBN引发 FA-MMA-BMA三元细乳液共聚合的主要成核场所为单体液滴 .即每个单体液滴都是一个独立的微型反应器 ,可避免因为单体水溶性的差异而使共聚组成产生漂移 .细乳液聚合合成含氟共聚物乳液的分子量分布窄 (1 .3～ 1 .5 ) ,乳液稳定性能好 ,共聚物在低含氟量下即表现出优异的疏水疏油性能 .

Stable fluoroacrylate copolymer emulsion in the size range of 110—150 nm was made by miniemulsion polymerization under employment of low dose of emulsifiers and no coemulsifiers, with fluoroacrylate(FA), butyl methylacrylate(BMA), methyl methyl-acrylate(MMA) as the monomers. The molecular weight and composition of copolymer were demonstrated by GPC, FTIR and 1H NMR, the change of latex partical sizer in the polymerization process was determined, and the surface property of films was studied by Wilhelmy method. It is shown that mixed monomer species allows efficient copolymerization to occur, and products with a high conversion of fluoromonomer(95%) and narrow molecular weight distribution(1.3—1.5) were obtained, and the polymer particles were found to be one-to-one copy of the monomer droplets and drop nucleation was the dominant mechanism in the polymerization process, some properties of fluoroacrylate copolymer latex of miniemulsion were improved, the excellent water and oil repellency of the copolymer film without coemulsifiers influence were preserved while the amount of fluorinated compounds required in the polymer is reduced considerably.