单分散聚苯乙烯乳胶粒的制备及其二维胶体晶体的自组装

以自合成的平均粒径为95.7 nm、粒径分布指数为0.047的聚苯乙烯乳胶粒为种子,采用种子乳液聚合方法制备出单分散的聚苯乙烯乳胶粒,探讨了控制胶粒粒径大小及分布的方法及制备条件.结果表明,在种子乳液聚合中,通过控制单体加入量和乳化剂的补加速度,可以得到单分散聚苯乙烯乳胶粒;当没有新的胶束生成且乳胶粒子没有发生聚结时,乳胶粒尺寸和分布有自身变窄的倾向,得到了平均粒径为261.6 nm、粒径分布指数为0.021的单分散乳胶粒.采用毛细管作用力驱动的微粒自组装技术进行单分散胶粒的组装,获得了二维有序聚苯乙烯胶体晶体,并用场发射扫描电子显微镜表征了其二维有序结构.

Preparation of Monodisperse Polystyrene Latex Particles and Self-Assembly of Two-Dimensional Ordered Colloidal Crystal of the Same

Monodisperse polystyrene latex particles were prepared via seed emulsion polymerization route, using polystyrene latex particles with an average grit size of 95.6 nm and grit size distribution index of 0.047 as the seeds. The optimization of the polymerization conditions and the methods to control the particle size and distribution were discussed. As the results, it was feasible to prepare monodisperse polystyrene latex by properly controlling the monomer content and the rate to introduce the emulsifying agent. When no additional new micelle was generated and the particles were not aggregated, the average size of the particles and the distribution tended to decline, and the filnal monodisperse emulsion particles had a size of 261.6 nm and grit size distribution index of 0.021. Moreover, it was able to use the monodisperse polystyrene latex particles to prepare two-dimensionally ordered polystyrene colloidal crystal using self-assembly driven by capillary force.