The Use of Thermogravimetric Analysis in Kinetic Studies of the Thermal Degradation of Polymers

Various thermogravimetric methods can be used to determine the activation energy and the rate constant of the pyrolysis of compounds, when only one mechanism is involved or when several mechanisms occur simultaneously with a relative extent which does not depend much on the temperature. Although the experimental results can be explained by simple kinetic theory, the mechanism of the pyrolysis is in most, if not all, cases much more complicated than is indicated by the thermogravimetric results. This is certainly true in the pyrolysis of polyethyleneglycol adipate. This does not reduce the interest of thermogravimetric analysis but illustrates the great difficulties which can be encountered in accounting for thermogravimetric measurements.