Polymer Bulletin, Vol.62, No.5, 615-627, 2009
Preparation of silica microtubes by surface-initiated atom transfer radical polymerization from microfiber templates
Poly(methyl methacrylate-co-vinylbenzyl chloride), P(MMA-co-VBC) microfibers (with submicron diameters) of about 1 mu m in size were prepared by electrospinning. Silyl-functional groups were introduced onto the P(MMA-co-VBC) microfibers templates via surface-initiated atom transfer radical polymerization of 3-(trimethoxysilyl)propyl methacrylate. The silyl groups were then converted into a silica shell, approximately 0.25 mu m thick, via a reaction with tetraethoxysilane in ethanolic ammonia. Hollow silica microfibers were finally generated by thermal decomposition of the P(MMA-co-VBC) template cores. Scanning electron microscopy and transmission electron microscopy were used to characterize the intermediate products and the hollow microtubes. Fourier-transform infrared spectroscopy results indicated that the polymer cores were completely decomposed. The microfibers were characterized by X-ray photoelectron spectroscopy, X-ray diffraction and the thermal gravimetric analysis.