Novel copolymers of vinyl acetate and ring-substituted ethyl 2-cyano-3-phenyl-2-propenoates, RPhCH=C(CN)CO2C2H5 (where R is 4-acetoxy, 4-acetamido, 2-cyano, 3-cyano, 4-cyano, 4-dimethylamino, 4-diethylamino, 2,4,6-trimethyl, 2,3-dimethyl-4-methoxy, 2,4-dimethoxy-3-methyl were prepared in solution with radical initiation at 70C. The propenoates were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and ethyl cyanoacetate, and characterized by CHN analysis, IR, 1H and 13C-NMR. The compositions of the copolymers were calculated from nitrogen analysis and the structures were analyzed by IR, 1H and 13C-NMR. Thermal behavior of the copolymers was studied by DSC (Tg) and TGA. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 160-350ºC range with residue (1.5-15.1 wt%), which then decomposed in the 500-650ºC range.