Graft polymerization of styrene from silica nanoparticles using a dispersion polymerization method

To enhance the interfacial interaction in silica-nanoparticle-filled polymer composites, an effective surface modification method was developed by grafting polystyrene onto the nanoparticles. That is, the silica surface was first treated with silane to introduce the methacryloxypropyl, followed by radical copolymerization with styrene via a dispersion polymerization method. Results of elemental analysis (EA), IR, XPS and TEM demonstrated that the desired polymer chains were covalently bonded to the surface of the silica nanoparticles. A percentage of grafting (PG) of 49.5% was achieved when 2.44 mmol AIBN was used as initiator. The resulting products could be used as nanocomposites directly, or the PS-grafted silica nanoparticles (PS-SNs) could be separated and used as nanofillers for polymers.