Abstract:Methyl methacrylate was grafted onto vinyl modified nano SiO2 through reversible addition-fragmentation chain transfer polymerization(RAFT) using azodiisobutyronitrile(AIBN) as initiator. Benzyl dithiobenzoate, benzyl dithiopivalate, tert-butyl dithiobenzoate, 1,2,4-triazolyl-1-carbodithioic acid benzyl ester, 1-phenylethyl dithiophenylacetate, 1-phenylethyl dithiobenzoate and 2-cyanoprop-2-yl dithiobenzoate were used as the RAFT agent, respectively. Grafting polymerization rate of methyl methacrylate onto nano-SiO2 mediated by benzyl dithiopivalate or 1-phenylethyl dithiophenylacetate is higher than that mediated by other RAFT agents with same R group. Grafting polymerization rate of methyl methacrylate onto nano SiO2 mediated by tert-butyl dithiobenzoate is higher than that mediated by other RAFT agents with same Z group. Grafting polymerization of styrene onto SiO2-PMMA could be conducted with end dithioester groups in the grafted chains of polymethyl methacrylate. Compared with other RAFT agents, grafting polymerization of styrene mediated by benzyl dithiobenzoate exhibits higher grafting ratio of polystyrene.