Investigation of the decomposition of copolymers of styrene and maleic anhydride using thermogravimetric analysis

The thermal decomposition of several copolymers of styrene (St) or α-methylstyrene (AMS) and maleic anhydride (MAn) were studied by non-isothermal TG in inert atmosphere. From TG data in the temperature range 573–723 K, the kinetic decomposition parameters were calculated using Ozawa's method. The activation energy of decomposition and pre-exponential factor for St/MAn copolymers were: E A = 191–225 kJ mol −1 , log A = 19.65–22.56 min −1 and for an AMS/MAn copolymer E A = 266 kJ mol −1 , log A = 26.84 min −1 , with a random degradation as the best-fitted mechanism for both types of copolymers. The relation between experimental results and structural characteristics of the copolymers is discussed.