采用预乳化种子半连续聚合的工艺,以反应性乳化剂代替小分子乳化剂,苯乙烯、甲基丙烯酸甲酯、丙烯酸丁酯、丙烯酸和丙烯酸羟乙酯为共聚单体,制备了无皂苯丙乳液,并使用固化剂对其进行交联固化,制备耐水性好的苯丙固化漆膜.通过傅里叶变换红外光谱(FT-IR)对苯丙聚合物及其固化漆膜进行了表征,探讨了反应性乳化剂用量对转化率、凝聚率、乳胶粒粒径、Zeta电位、乳液稳定性及其苯丙固化漆膜性能的影响.结果表明,反应性乳化剂与苯丙单体进行了共聚,固化剂与苯丙树脂产生了固化交联反应.随着反应性乳化剂用量的增加,单体转化率提高,凝聚率降低,乳胶粒粒径减小,乳胶粒表面所带电荷增多,乳液稳定性提高.当乳化剂用量为3%时,苯丙固化漆膜耐水性最好,此时固化漆膜在40℃去离子水中浸泡10天不发白和不脱落.%The soap-free styrene-acrylic emulsion was prepared by seed semi-continuous polymerization using re-active emulsifier instead of small molecule emulsifier,and styrene,methyl methacrylate,butyl acrylate,acrylic acid and 2-hydroethyl methacrylate as co-monomers. Then the styrene-acrylic emulsion was cured by curing agent and the curing film with good water resistance was obtained. The chemical structure of the styrene-acrylic copolymer and its curing film was characterized by Fourier transform infrared (FT-IR). The effects of reactive emulsifier content on the monomer conversion,coagulation rate,particle size,Zeta potential,latex stability of styrene-acrylic emulsion, as well as properties of curing film were investigated. The results showed that the reactive emulsifier took part in the copolymerization with other monomers, and the curing reaction occurred between curing agent and styrene-acrylic copolymer. With the increase of reactive emulsifier content,the monomer conversion and electric charge of the latex surface increased while the coagulation rate and particle size of latex decreased,resulting in the better stability of the latex. When the reactive emulsifier content was 3%,the styrene-acrylic curing film possessed good water resistance for the curing film could not exfoliated from the substrate or got white after immersed in water at 40℃ over 10 days.
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