Optimum temperature for oxidative degradation of poly(vinyl acetate) in solution

Abstract

The oxidative degradation of poly(vinyl acetate) (PVAc) was carried out in presence of benzoyl peroxide at 70–123°C in a batch reactor by dissolving PVAc in chlorobenzene. The molecular weight distributions (MWDs) were measured as a function of reaction time by gel permeation chromatography. Experimental data indicates degradation occurs by random chain scission only without cross-linking and repolymerization. A radical mechanism for the oxidative degradation was proposed and modeled based on continuous distribution kinetics. An optimum temperature of 110°C was observed for maximum degradation. The energy of activation of the random scission oxidative degradation rate coefficient, determined from the temperature dependence, was 20 kcal/ mol .