Study On Bulk Copolymerization Of MMA And Its Properties

Mainly aimed at the problems of high viscosity, slow heat-transfer, and easy to produce gel effect in continuous bulk polymerization for preparing PMMA resin at high temperature in industry production. The bulk copolymerization of methyl methacrylate (MMA) and dicyclopentanyl methacrylate (HDCPMA) was performed respectively at room temperature (80～90℃) and elevated temperature (>110℃). The properties of copolymer prepared at different temperature was studied. The effect of viscosity on the reactivity ratio and the reaction rate was also investigated.The copolymer P(HDCPMA-co-MMA) prepared in bulk polymerization was characterized by NMR, GC, GPS, UV-Vis, DSC, TG, etc. The structure and properties of copolymer was investigated, depending on monomer HDCPMA and temperature. The reactivity ratio was calculated by FR, K-T and YBR methods. The result indicates that monomer HDCPMA can be used to improve glass transition temperature of PMMA, maintain its transmittance and increase the molecular size of the copolymer. The reactivity ratio of HDCPMA decreases from 1.0986 to 0.5460 and the reactivity ratio of MMA increases from 2.5343 to 4.3096. The polymerization is accelerated with temperature elevated, and polymerization temperature predominantly affects the reaction rate of HDCPMA.The result shows that the reactivity ratio of HDCPMA increases from 1.0986 to 4.6425, the reactivity ratio of MMA decreases from 2.5343 to 2.1132 and polymerization rate decelerates with the viscosity increased in bulk polymerization. Meanwhile, in the bulk polymerization at room temperature, the reactivity ratio of MMA reduces from 1.8419 to 1.0734 and the reactivity ratio of MA reduces from 0.6076 to 0.5022 with the viscosity increased.