On the thermal degradation of poly(styrene sulfone)s. V. Thermogravimetric kinetic simulation of polyacrylamide pyrolysis

The kinetics involved in the thermal degradation of polyacrylamide under nitrogen atmosphere were studied by using consecutive reactions of a kinetic model to dynamic thermogravimetric data. The model proposed correlates the thermograms obtained at thermogravimetric and differential thermogravimetric data with the same set of kinetic parameters. The first stage of polyacrylamide decomposition, where the deamonation of the polyacrylamide and the dehydration of acrylamide units and the formation of a proportion of unvolatile imides and nitrile and aliphatic organic compounds can be fitted satisfactorily when in a model based on a single reaction. The second stage, corresponding to the breakdown of the imides formed and the polymer back-boric, also can be correctly represented by a model based on a single reaction. In this article, a discussion about the applicability of the model is, presented and the results obtained are compared to those obtained by Flynns's and Friedman's analytical methods, respectively. The maximum decomposition temperature, shape index for dynamic condition and lifetime, and degree of decomposition for isothermal condition of thermal behavior of polyacrylamide are predicted via mathematical simulation. (C) 2002 Wiley, Periodicals, Inc.