Synthesis and styrene copolymerization of novel bromo, chloro, methoxy, and methyl ring-disubstituted isobutyl phenylcyanoacrylates

Novel ring-disubstituted isobutyl phenylcyanoacrylates, RPhCH=C(CN)CO2CH2CH(CH3)2 (where R is 2-bromo-3-methoxy, 2-bromo-5-methoxy, 3-bromo-4-methoxy, 5-bromo-2-methoxy, 2-bromo-4-methyl, 2-chloro-3-methoxy, 3-chloro-4-methoxy, 3-chloro-4-methyl) were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-disubstituted benzaldehydes and isobutyl cyanoacetate and characterized by CHN analysis, IR, 1H and 13C NMR. The acrylates were copolymerized with styrene in solution with radical initiation (ABCN) at 70C. The compositions of the copolymers were between 19.6 and 32.6 mol% of acrylates. Weight-average molecular masses of the copolymers were 41.3 - 54.5kD. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 248-500ºC range with residue (1.5-6.1% wt), which then decomposed in the 500-800ºC range.