超细聚甲基硅氧烷微球的制备

Synthesis of the Polymethylsiloxane Microspheres in Micron Size

采用水解-缩聚两步法以甲基三甲氧基硅烷(MTMS)为原料制备微米级聚甲基硅氧烷微球,粒径为1～15μm,粒径分布较窄;就反应体系pH值、油水比等条件对微球粒径大小、形态及其分布的影响进行了研究.结果表明,较优的反应条件为:在水解过程应控制pH=4.0～6.0之间,投料油水比(MTMS与水的摩尔比)应小于1/4,缩聚过程控制pH=7.0～9.0之间;随着油水比的增大以及缩聚反应中pH值的降低,微球的粒径增大,分布变宽.

Polysiloxane microspheres were prepared by the sol-gel polymerization method from methyltrimethoxysilane （MTMS）. The particle size is from 1μm to 15μm and the size distribution is narrow （C. V. ）. Effects of the reaction parameters, such as pH value and the ratio of oil to water on particle size, shape and distribution were investigated. The results indicate that the preferred preparation conditions are pH value in 4.0-6.0, ratio of O/W 〈1/4 in hydrolysis reaction and pH value in 7.0-9.0 for condensation reaction. With the increasing of O/W ratio and the decreasing of pH value in condensation reaction, the particle size is increase and the size distribution broadens.