Kinetic Analysis of Thermal Degradation of Polypropylene Using a Modified Gompertz Model

Abstract

A new method, called modified Gompertz model, was proposed to interpret solid state decomposition. To verify the validity of this new model, the thermal degradation of polypropylene (PP) was performed and the results of curves fitting of thermogravimetry (TG) and derivative thermogravimetrical (DTG) from the Gompertz model were compared with those obtained from the traditional general model. The Arrhenius kinetic parameters used in the general model were derived from three traditional methods (i.e., Friedman, Freeman-Carroll, and Ozawa methods). For the Arrhenius parameters calculation, the heating temperature range was set from 298 to 1073 K and three different heating rates of 5, 10, and 15 K/min were selected. The sum of square errors (SSE) and the coefficient of determination ( r2 ) were calculated for all simulated data obtained from the modified Gompertz model and the general model. Statistical results show that all SSE values obtained from the modified Gompertz model are much smaller than those fr...