Terpolymerization of styrene, acrylonitrile and chromium acrylate: synthesis and properties

Solution terpolymerization of styrene, acrylonitrile and chromium acrylate has been carried out in dimethylformamide at 85°C using styrene-arsenic sulfide complex as radical initiator. 1H nuclear magnetic resonance (n.m.r.), infra-red (i.r.) and elemental analysis have been used to characterize the terpolymer. Data from 1H n.m.r., elemental analysis and gravimetric analysis have been used to evaluate terpolymer composition. Reactivity ratios (calculated from Finemann-Ross method as r1(Sty) = 5 ± 2 r2(AN + CrA) = 0.15 + 0.02) and composition confirm its random origin. The terpolymer was highly thermally stable and has a glass transition temperature of 96°C as evaluated from differential scanning calorimetry studies.