Synthesis and characterization of co-polymers of styrene with acrylonitrile initiated by p-acetylbenzylidene triphenylarsonium ylide

Abstract

p-Acetylbenzylidene triphenylarsonium ylide (p-ABTAY) initiated free radical co-polymerization of styrene (Sty) with acrylonitrile (AN) in dioxane, at 60 ± 0.1°C for 1 h, under the inert atmosphere of nitrogen results an alternating co-polymer. The system follows ideal kinetics (R p α [p-ABTAY]0.5 [Sty] [AN]). The activation energy has been computed to be 30 kJ/mol. The FT-IR spectra of the co-polymers show bands at 3054 cm−1 and 2238 cm−1 due to styrene and acrylonitrile, respectively. The 13C-NMR spectra of the co-polymer show peaks at 120–123 δ ppm and 127–132 δ ppm due to —CN of acrylonitrile and phenyl carbon of styrene, respectively. The reactivity ratios have been calculated, using the Kelen–Tüdos method, to be r 1(Sty)= 0.0067 and r 2 (AN)= 0.082. The formation of phenyl radicals may be attributed to the p π –d π overlap between the hybridized sp2 orbital and more diffused 4d orbital of arsenic.