Kinetics and mechanism of the thermal degradation of poly-p-chloromethylstyrene. Thermogravimetric and gas chromatography-mass spectrometry studies

Abstract

The kinetics and mechanism of the thermal degradation of poly-p-chloromethylstyrene were studied by gas chromatography-mass spectrometry and isothermal and dynamic thermogravimetry. Two stages are observed. The first one begins at about 285°C and ends at about 400°C. The corresponding weight loss is about 40%. The global weight loss is about 70% at 560°C. The main products, released from the first stage, are hydrogen chloride and monomer. Isothermal rates calculated from a kinetic model based on random initiation, depropagation and termination are in good agreement with experimental values for α between 0.2 and 0.6. Beyond this, the kinetic law becomes more complex. The overall activation energy for the first stage was found to be 165.6 kJ mole-1 and the pre-exponential factor 6.24·1012 min-1. © 1988.