Application of distributed activation energy models to polymer pyrolysis: Effects of distributed model selection, characteristics, validation, and sensitivity analysis

In this study for exploring the pyrolysis mechanism and kinetics prediction, distributed activation energy models (DAEMs) were employed and developed to fit the pyrolysis processes of three typical polymers, PMMA (polymethyl methacrylate), PS (polystyrene), and RPU (rigid polyurethane). Four kinds of activation energy distributions covering Gaussian, Logistic, Uniform, and Weibull were selected to explore the best models with firstorder and nth-order reaction function. Each model was fitted with both extracted experimental a and da/dT data at three heating rates simultaneously to avoid the ill-conditioned behavior. Based on the obtained models, important characteristics and relationships of these models were discussed with a best model selected. In addition, the best model was then validated with isoconversional method and sensitivity of the optimal parameters was estimated.