苯丙-硅溶胶纳米复合乳液的制备及其性能

Study on polymerization and performance of styrene acrylate/silica nanocomposite latex

采用原位乳液聚合法制备了苯丙-硅溶胶纳米复合乳液,系统研究了乳化剂种类和用量对乳液稳定性、乳胶膜吸水率以及乳胶粒子粒径的影响.结果表明:相比单独使用,十二烷基硫酸钠(SDS)与壬基酚聚氧化乙烯基醚(OP-10)按质量比为2∶1复配时制备的乳液稳定性最好;当乳化剂用量为0.75%～1.5%时,所制复合乳液稳定性好,乳胶膜的吸水率为3.64%～5.72%.与共混乳液(硅溶胶和苯丙乳液的共混物)和苯丙乳液的乳胶膜相比,复合乳胶膜的吸水率显著降低;透射电子显微镜(TEM)检测结果表明:与共混乳液相比,复合乳液中游离的纳米SiO2粒子数大大减少.

The styrene-acrylate/silica nanocomposite latex was synthesized by in-situ emulsion polymerization.The influence of the type and content of emulsifier on the emulsion polymerization stabilities,water absorption rate of latex film and the size of the latex were studied systematically.The results indicated that the emulsion polymerization stabilities were best when the emulsifier of SDS and OP-10 were used with a mass ratio of 2∶1;when the emulsifier content used was in the range of 0.75%～1.5%,the obtained latex showed good stability and the water absorption rate was as low as 3.64%～5.72%.The nanocomposite latex film showed lower water absorption rate than those formed by the pure styrene-acrylic emulsion and the physical mixture of styrene-acrylic emulsion and silica sol.The TEM results showed that the number of free SiO2 particles in nanocomposite latex was much less than that in the mixture of styrene-acrylic emulsion and silica sol.