Synthesis Of Ethylene-Propylene Rubber Graft Copolymers

In this dissertation, ethylene-propylene rubber graft copolymers were prepared by using atom transfer radical polymerization (ATRP), anionic coupling technique and emulsion polymerization. Their molecular weights, molecular weight distributions and structures were characterized by GPC and H NMR.By ATRP method, the EPDM backbone is brominated with N-bromosuccinimmide (NBS) to introduce allyl bromine on the backbone first, and then the brominated backbone (EPDM-Br) is used as macroinitiator, conjunction with CuBr/bpy to initiate the polymerization of styrene. The EPDM graft copolymers with different well-controlled structure can be easily synthesized through controlling bromine content. Thermally polymerization of styrene in these reaction systems were studied in detail. Higher temperatures and long reaction time made thermal initiate more evidently.Using anionic coupling technique, Ethylene-propylene rubber (EPR) graft copolymers with well-defined structure were prepared successfully between chlorinated EPR (Cl-EPR) and living anionic polystyrene chain. The Cl-EPR was obtained by chloride substitution reaction between chloride gas and EPR, and then coupling with anionic living polystyrene. The EPR-g-styrene was characterized by hydrogen nuclear magnetic resonance (H NMR) and gel penetration chromatogram (GPC). The amount of living PS and chloride content would be affected the graft percent and graft efficiency.Acrylonitrile-EPDM-styrene(AES) graft copolymers were prepared by seed-emulsion graft polymerization of styrene( St) and acrylonitrile(AN) onto EPDM with disproportionated rosin potassium salt as emulsifier and KSO (KPS) as initiator. The influence of the polymerization conditions on particle diameter , grafting percent and grafting efficiency was investigated.