Thermal degradation of biomedical polyurethanes—A kinetic study using high‐resolution thermogravimetry

The kinetics of thermal degradation of polyurethanes (PUR) has been studied by means of high‐resolution and constant heating rate thermogravimetry (TG), under nitrogen and synthetic air atmospheres. The high‐resolution TG provided a way to increase resolution with decreasing the time of data acquisition. In this mode, the heating rate is dynamically varied to maximize resolution. A method to calculate the kinetic parameters from this technique was used. The TG curves showed two or three decomposition steps, depending on the atmosphere employed. The parameters calculated for the PUR decomposition were the activation energy, reaction order, and preexponential factor. A method to estimate the polymer lifetime was also used. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 910–919, 2001