Synthesis and Styrene Copolymerization of Novel Ring-Disubstituted Isopropyl Cyanoarylacrylates
Novel oxy ring-substituted isopropyl 2-cyano-3-arylacrylates, RPhCH=C(CN)CO2CH(CH3)2 (where R is 3,4-dibenzyloxy, 3-benzyloxy-4-methoxy, 4-benzyloxy-3-methoxy, 2,3-methylenedioxy, 3-iodo-4-methoxy, 5-iodo-2-methoxy, 3,4-difluoro, 3,5-difluoro) were prepared and copolymerized with styrene. The acrylates were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-disubstituted benzaldehydes and isopropyl cyanoacetate and characterized by CHN elemental analysis, FTIR, 1H and 13C-NMR. All the acrylates were copolymerized with styrene in solution with radical initiation (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by FTIR, 1H and 13C-NMR. Thermal properties of the copolymers are characterized by DSC and TGA. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200-500ºC range with a residue, which then decomposed in the 500-800ºC range.