Novel co-polymers of vinyl acetate and alkyl ring-substituted methyl 2-cyano-3-phenyl-2-propenoates.

Electrophilic trisubstituted ethylene monomers, ring-substituted methyl 2-cyano-3-phenyl2-propenoates, RC6H4CH=C(CN)CO2 CH3 (where R = H, 2-CH3, 3-CH3, 4-CH3, 2-C2H5, 4-C2H5, 4-iC3H7, 4-C4H9 and 2,4,6-(CH3)3), were synthesized by the piperidine-catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and methyl cyanoacetate, and characterized by CHN elemental analysis, IR, 1H- and 13C-NMR. Co-polymerization of the propenoates and vinyl acetate in solution with radical initiation (AIBN) at 70°C yielded equimolar alternating co-polymers. The composition of the co-polymers was calculated from nitrogen analysis and the structures were analyzed by IR, 1H- and 13C-NMR, GPC, DSC and TGA. The high Tg of the co-polymers in comparison with that of polyvinyl acetate indicates a substantial decrease in chain mobility of the co-polymer due to the high dipolar character of the trisubstituted ethylene monomer unit. The gravimetric analysis indicated that the co-polymers decompose in the 214–400°C range. [ABSTRACT FROM AUTHOR]