NOVEL SILANOL-CONTAINING POLYMERS AND THEIR BLENDS

Novel 4-vinylphenyldimethylsilanol polymer (PVPDMS) and copolymers (ST -VPDMS) were synthesized by the oxyfunctionalization re action of the silane. The reaction was found to proceed efficiently and quantitative ly. Miscibility studies indicated that about 4 mol% of 4-vinylphenyldi methylsilanol (VPDMS) functional group in the copolymer could achieve miscibility with poly(n-butyl methacrylate) (PBMA) and poly(N-vinylpyr rolidone) (PVPr). However, for copolymers containing more than 34 mol% VPDMS, their blends with PBMA were immiscible. The observed miscibili ty window of ST-VPDMS/PBMA blends was ascribed to the competition betw een the self-association of dimethylsilanol groups and intermolecular hydrogen bonding of dimethylsilanol groups with the carbonyl groups of PBMA. A comparison of the efficiency of the miscibility enhancement a nd the miscibility windows of VPDMS, p-(hexafluoro-2-isopropyl) styren e (HFPS), and phenolic-containing polymers was made in terms of such c ompetition. The glass transition behavior of the miscible blends invol ving VPDMS and HFPS-containing styrene copolymers with PBMA were analy zed by the Schneider equation.