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Equimolar alternating co-polymers of vinyl acetate and electrophilic trisubstituted ethylene monomers, halogen ring-substituted methyl (E)-2-cyano-3-phenyl-2-propenoates, RC6H4CH=C(CN)CO2CH3 (where R = 2-Br, 3-Br, 4-Br, 2-Cl, 3-Cl, 4-Cl, 2-F, 3-F, 4-F), were prepared via co-polymerization in solution with radical initiation (ABCN) at 70°C. The compositions of the co-polymers were calculated from nitrogen analysis and the structures were analyzed by IR, 1H- and 13C-NMR. High glass transition temperatures of the co-polymers in comparison with that of polyvinyl acetate indicate a decrease in chain mobility of the co-polymers due to the high dipolar character of the tri-substituted ethylene monomer unit. The gravimetric analysis indicated that the decomposition of the co-polymers occurs in two steps. The first step is relatively fast weight loss in 227–370°C range, followed by very slow decomposition of the formed residue in 370–950°C range. [ABSTRACT FROM AUTHOR]

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]