TABLE OF CONTENTS The changes in experimental conditions on going from isothermal to programmed temperature measurements are neither minor nor trivial. The "warm up" period required to reach isothermal conditions is a well-known source of kinetic distortion, but experiments at different heating rates can result in different temperature gradients in the samples which unless corrected for may also lead to erroneous kinetic conclusions. There has also been extensive discussion [45], [46] of the applicability under nonisothermal conditions of the Avrami-Erofeev (or JMAEK) equation (see Table 10.1), which is based on a model that includes contributions from the distinct processes of nucleation and of product growth which may have very different temperature dependences.
The traditional classification of methods used in the analysis of the nonisothermal kinetic data has usually been to distinguish differential methods, based on use of equation (10.1), from integral methods, based on use of equation (10.2). Vyazovkin and Lesnikovich [47] criticized this conventional classification because it refers to the type of experimental data used. They suggested instead a classification based on the method of calculation of the kinetic parameters, which involves either " discrimination", i.e. identification of the kinetic model f( ?) or g( ?), or a " non-discriminatory" method. An alternative name for non-discriminatory methods is "model-free methods", but this tends to give the unfortunate and incorrect impression that the kinetic model f( ?) or g
