The study of the copolymerization of styrene and acrylonitrile to high conversion. application of low conversion reactivity ratios

The copolymerization of styrene and acrylonitrile has been investigated with the purpose of predicting the changes in copolymer composition and comonomer sequence distribution with increasing conversion. Toluene was used as the solvent and the copolymerization was examined initially under low conversion conditions to determine whether the terminal or the penultimate model best described the polymerization. The penultimate model was found to provide the best fit to both the experimental composition and triad fraction data. The reactivity ratios (for the penultimate model) were then used to predict the changes in copolymer composition and triad fractions with conversion. The results show that the penultimate model provides an excellent prediction for the polymerization across the complete conversion range for all comonomer feed compositions