Preparation and characterization of polystyrene grafted nano-sized silica

The radical copolymerization of styrene with the vinyl groups introduced onto the surface of the nano-sized silica via solvent polymerization method was developed. γ-Methacryloxy propyltriethoxysilane (MPTES) was used as coupling agent to introduce vinyl groups onto surfaces of the nano-sized silica. The methacryloxypropyl nanosized silica (MPNS) was used as macromonomer and copolymerized with styrene by initiating with AIBN in toluene. The conversion (C), percentage of grafting (PG) and grafting efficiency (GE) were found to be 60.7%, 24.0% and 1.31% from the elemental analysis results, respectively. It was found that the surface of the nano-sized silica could be covered by PS chains efficiently so as to improve the dispersibility of the nano-sized silica in organic matrices. The addition of the nano-sized silica could improve the thermal stability of PS.