Analysis of Most Probable Mechanism Functions and Thermal Degradation Kinetics of N-Phenylmaleimide-Styrene-Maleic Copolymers

The thermal degradation kinetics of N-phenylmaleimide-styrene-maleic (NSMA) anhydride copolymers was analysed by a non-isothermal kinetic method. Kinetic parameters were obtained using integral and differential methods, and the most probable mechanism functions and kinetic compensation effects were discussed. The activation energy E for the thermal degradation of NSMA was 211.34kJ/mol according to the Flynn-Wall-Ozawa method and the thermal degradation was a first-order chemical reaction. A recommended rate expression for the thermal degradation reaction of NSMA was d α d t = A e − E R T ( 1 − α ) (where α is the conversion, t is time, R is the gas constant, T is the temperature and A is the pre-exponential factor), and the mathematical expressions of compensation effects for the integral and differential methods were lnA=-1.8037+0.1749E and lnA=-2.1974+0.1741E respectively.