影响硅丙微乳液乳胶粒粒径的因素

Elements which affect the grain size of silicone-acrylate copolymer microemulsion

采用常规的阴离子及非离子型乳化剂制得了带有蓝色荧光的半透明O/W硅丙微乳液。讨论了聚合方法、乙烯基二甲基乙氧基硅烷用量、乳液固含量对硅丙微乳液乳胶粒粒径及其分布的影响。结果表明,采用高温乳化种子乳液聚合法制备硅丙微乳液,所需乳化剂用量少、总反应时间短,所得粒子粒径小、分布窄;当乙烯基二甲基乙氧基硅烷用量为单体总质量的30%时,乳胶粒的粒径最小;当乙烯基二甲基乙氧基硅烷用量为单体总质量的40%时,乳胶粒的粒径分布最窄;当乳化剂质量分数为5%、乙烯基二甲基乙氧基硅烷质量分数为30%、乳液固含量达37·5%时,微乳液乳胶粒的平均粒径为57·7nm,聚合分散系数为0·084。

The blue semi-transparent and stable O/W microemulsion was obtained by the synthesis of the common anionic and nonionic emulsifiers. The effects of polymerization methods, the mass fraction of copolymer and the content of silicone on the grain size and the distribution of the microemulsion were investigated. The result showed that with small amount emulsifier and short time, when the silicone-acrylate microemulsion was prepared by high temperature emulsification seed polymerization, the particle size was small and narrow distribution. When the content of methyldimethoxy(vinyl)silane was 30% of the monomer mass, the grain size of the latex was minimum; however, when the content of methyldimethoxy(vinyl)silane was 40% of the monomer mass, the distribution of grain size of the latex was narrowest.