Kinetics of pyrolysis of high density polyethylene. Comparison of isothermal and dynamic experiments

An experimental study of the thermal decomposition of high density polyethylene in an inert atmosphere has been carried out. Both isothermal and dynamic experiments at different heating rates have been performed in a thermobalance. The objective of this work is to analyse the applicability of a simple first-order equation to the prediction of the weight loss of the material, taking into account the complex chain reaction mechanism. The corresponding kinetic parameters have been obtained and its applicability at different heating rates has been analysed. The isoconversion method of Ozawa-Flynn-Wall has been used to obtain the activation energy and the frequency factor from non-isothermal experiments and compare them with the values obtained from isothermal experiments and with the results obtained by other authors. (C) 2002 Elsevier Science B.V. All rights reserved.