Copolymerization of N-(4-Vinylpfaenyi)maleunide with Styrene and N-Phenylmaleimide and Thermal Properties of the Copolymers

In order to synthesize linear polymers with crosslinkable pendant unsaturated groups, copolymerizations of N-(4-vmylphenyl)maleimide (VPMI) with N-phenyunaleimide (PMI) and styrene (St) were carried out. VPMI possesses two polymerizable carbon-carbon double bonds with different reactivities. Poly(VPMI-co-PMI)M, obtained by anionic copolymerization with potassium lert-butoxide as an initiator had both VPMI and PMI units, and the VPMI unit possessed a pendant styrene group. Poly(VPMi-co-St)st obtained by cationic copolymerization initiated by tri-fluoroboran etherate had both VPMI with a pendant maleimide group and St units. Thermal properties of the copolymers were examined by DSC and TGA. Every PoWVPMI-co-PMOm, had no obvious melting point. Thermal decomposition temperatures of these copolymers were 411~434°C, which were not influenced by the composition. Poly-(VPMI-eo-St)s, which contained more than 60 mol% St unit showed a melting point. The thermal decomposition temperature of poly{VPMI-ro-St)Sl decreased with increasing content of St unit. Poly(VPMI-co-St)St decomposed at 384 ~461°C. The decomposition temperatures of these copolymers were higher than that of polystyrene.