Temperature‐induced transformations of peroxide radicals formed in polytetrafluoroethylene with γ‐ray irradiation

At 200°C, temperature‐induced transformations of peroxide radicals from CF2CF(OO·)CF2 (radical I) to CF2CFCF2 (radical 1) and CF2CF2OO· (radical II) to CF2CF2 (radical 2) in vacuo, and from I to II in oxygen atmosphere were observed. In these thermal transformations, the evolution of CO2 with a small amount of CO and CF2O was observed. Further, measurements of the heat of crystallization of the treated polytetrafluoroethylene suggest that a reduction of polymer molecular weight occurs during the transformations from I to 1 and I to II.