Preparation of hollow silica nanospheres by surface-initiated atom transfer radical polymerization on polymer latex templates

Poly(vinylbenzyl chloride), (PVBC) latex particles of about 100 nm in size are prepared by emulsion polymerization. Silyl functional groups are introduced onto the PVBC-nanoparticle templates via surface-initiated atom transfer radical polymerization of 3-(trimethoxysilyl)propyl methacrylate. The silyl groups are then converted into a silica shell, approximately 20 nm thick, via a reaction with tetraethoxysilane in ethanolic ammonia. Hollow silica nanospheres are finally generated by thermal decomposition of the PVBC template cores. Field-emission scanning electron microscopy and field-emission transmission electron microscopy are used to characterize the intermediate products and the hollow nanospheres. Fourier-transform infrared spectroscopy results indicate that the polymer cores are completely decomposed.