The kinetics of thermal degradation of poly (aryl ether ether ketone) and sulfonated PEEK was studied by isothermal and dynamic thermogravimetry. The results calculated from the kinetic models based on random initiation followed by rapid disproportionation and termination were in good agreement with the experimental data. The overall activation energy for the degradation was found to be 235 KJ/mol. The effect of sulfonatiorr on thermal degradation was also mentioned. It is noted there are two weight loss steps in the dynamic TG curves for S-PEEK. Compared with thetemperature programing PGC-MS data

the thermal degradation behaviour of S-PEEK was discussed here.