可聚合阳离子含氟表面活性剂在含氟丙烯酸酯乳液聚合中的应用

Application of Polymerizable Cationic Fluorosurfactants in the Emulsion Polymerization of Fluorinated acrylate

摘要:

以可聚合阳离子含氟表面活性剂N-（乙酸全氟辛基乙基酯）-N-（乙醇丙烯酸酯）二甲基溴化铵（PF8DM）为乳化剂，进行含氟丙烯酸酯的细乳液聚合研究，考察了PF8DM用量对单体转化率和凝胶率的影响；研究了PF8DM用量对乳液的稳定性和表面性能的影响；分别采用PF8DM和十六烷基三甲基溴化铵作为乳化剂考察其对乳胶膜性能的影响。结果表明，当PF8DM含量为单体总质量的4 %时，单体转化率达95%，凝胶率为0.6%；所得乳液具有优异的贮存、稀释、离心稳定性；当PF8DM用量为单体总质量的6 %时得到的乳胶膜接触角达118.6°。在总含氟量相同的条件下，采用PF8DM为乳化剂制备的含氟丙烯酸酯乳液，其乳胶膜的吸水率大大降低，拒水性也明显增强。

Abstract:

Fluorinated polyacrylate emulsion was synthesized via miniemulsion polymerization based on N-(perfluoro-octyl acetate, ethyl)-N-(ethanol acrylate) dimethyl ammonium bromide (PF8DM) as polymerizable cationic surfactant. The effect of the PF8DM content on the conversion rate of monomer and coagulum content was investigated; the impact of the PF8DM content on the emulsion stability and the film surface properties was studied. A comparative study of the surface properties of latex films prepared respectively by PF8DM and cetyltrimethylammonium bromideas as emulsifier was carried out. The results show that the monomer conversion rate is 95% and the gel rate is 0.6% when PF8DM content is 4 wt%. The as-prepared emulsion has excellent storage, dilution and centrifugal stability. The water contact angle of latex film is 118.6°when PF8DM content is 6 wt% . The latex film has low water absorption and excellent water repellent properties as the bonding rate of PF8DM reaches 89.4%. Under the same condition of the total fluorine content, the water absorption of latex film was greatly reduced and its hydrophobicity was enhanced significantly.