Preparation of poly (methyl methacrylate)/nanometer calcium carbonate composite by in-situ emulsion polymerization

Methyl methacrylate (MMA) emulsion polymerization in the presence of nanometer calcium carbonate (nano-CaCO(3)) surface modified with gamma-methacryloxypropyltrimethoxysilane (MPTMS) was carried out to prepare poly (methyl methacrylate) (PMMA)/nano-CaCO(3) composite. The reaction between nano-CaCO(3) and MPTMS, and the grafting of PMMA onto nano-CaCO(3) were confirmed by infrared spectrum. The grafting ratio and grafting efficiency of PMMA on nano-CaCO(3) modified with MPTMS were much higher than that on nano-CaCO(3) modified with stearic acid. The grafting ratio of PMMA increased as the weight ratio between MMA and nano-CaCO(3) increased, while the grafting efficiency of PMMA decreased. Transmission electron micrograph showed that nano-CaCO(3) covered with PMMA was formed by in-situ emulsion polymerization.