Abstract
The specific features for the synthesis of periodic polymers with the 1,1-diphenylethylene (DPE) derivatives were investigated via living anionic copolymerization. Thus, three DPE derivatives, including dimethyl-[4-(1-phenylvinyl) phenyl] silane (DPE-SiH), 1,1-diphenylethylene (DPE) and 1-propyl-4-(1-phenylvinyl) benzene (DPE-propyl), were selected for living anionic copolymerization with styrene (St) under regulated feed ratios. Real-time in situ H-1 NMR method was applied to monitor the whole chain propagation process to investigate the detail kinetics of the formation of periodic structures and corresponding sequence distribution in chain. Through the real time H-1 NMR monitoring, the special phenomena were observed that kinetic curves of DPE derivatives and St showed almost coincide and the apparent kinetic parameters were nearly equal in broad feed ratios. Meanwhile, the in situ H-1 NMR results indicated that a series of periodic structure, in which the DSDSS or DSS repeating patterns dominantly distributed along the chains, were deduced and the sequence structures are determined by the feed ratios and the reactivity of corresponding DPE derivatives. The glass transition temperatures (T(g)s) of the resultant copolymers have been tested to investigate the influence of the repeating patterns on the thermal properties.