聚苯乙烯/二氧化硅（PS/SiO2）核壳型微球及SiO2空心球的可控制备及电镜观察

CONTROLLABLE PREPARATION AND ELECTRON MICROSCOPY OF PS/SiO2 CORE/SHELL MICROSPHERES AND HOLLOW SiO2 MICROSPHERES

采用一种简单和低成本的方法制备单分散二氧化硅包覆聚苯乙烯（PS/SiO2）核壳型纳米复合微球.首先在氨水的醇溶液中,将聚乙烯吡咯烷酮（PVP）通过乳液聚合为聚苯乙烯核心,再在核心表面使正硅酸四乙酯（TEOS）水解缩聚,从而在PS微球表面包裹一层SiO2外壳.研究了氨水的用量对PS/SiO2纳米复合微球尺寸和形态的影响,利用透射电子显微镜（TEM）和扫描电子显微镜（SEM）对样品的超微结构与形貌进行表征,并探讨了其形成机理.

The monodisperse SiO2-coated polystyrene （PS） （PS/SiO2） core/shell nanocomposite microspheres were prepared by a simple and low-cost method.PS cores were polymerized by polyvinylpyrrolidones （PVP） through emulsion in the ethanol/NH4OH solution.Then,the hydrolysis and polycondensation of the four ethyl orthosilicate （TEOS） make the cores covered by SiO2 coat.Results show that the amount of NH4OH （H2O）influences the morphology and size of samples.At the same time,the ultrastructure and morphology of the samples were characterized by using transmission electron microscopy（TEM） and scanning electron microscopy（SEM）.The formation mechanism of PS/SiO2 core/shell structure and the hollow SiO2 microspheres were discussed.