Synthesis and styrene copolymerization of novel alkoxy ring-substituted isobutyl phenylcyanoacrylates

Novel alkoxy ring-substituted isobutyl phenylcyanoacrylates, RPhCH=C(CN)CO2CH2CH(CH3)2 (where R is 2-methoxy, 3-methoxy, 4-methoxy, 2-ethoxy, 3-ethoxy, 4-ethoxy, 4-propoxy, 4-butoxy, 4-hexyloxy) were prepared and copolymerized with styrene. The acrylates were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and isobutyl cyanoacetate and characterized by CHN elemental analysis, IR, 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 IR, 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 residue (1.8-3.3% wt.), which then decomposed in the 500-800ºC range.