Studies on thermal stability and nonisothermal thermal decomposition kinetics of vinyl chloride-vinyl acetate copolymer prepared via microsuspension polymerization

The thermal stability and nonisothermal thermal decomposition kinetics of t he vinyl chloride-vinyl acetate copolymer synthesized via microsuspension p olymerization (MS-VC/VAc) were studied by dynamic TG. The results showed th at MS-VC/VAc gives off hydrogen chloride and acetic acid (HAc) at the same time when it was heated. VAc content produces little effect on the thermal stability and the kinetic parameters. The activation energy for giving off HCl and HAc is in the range of 120-160 kJ/mol and the Arrhenius frequency f actor 3.27 x 10(9)-9.72 x 10(12) s(-1). For different heating rates, the ki netic model function of the thermal decomposition obeys the Avrami-Erofeev model equation, that is, [-ln(1-a)](1/m) for g(a), where m = 0.65-0.85. (C) 2000 John Wiley & Sons, Inc.