Electron and gamma irradiation‐induced effects in poly(ethylene‐co‐tetrafluoroethylene) films

Abstract

The effect of high-energy radiation in poly(ethylene-co-tetrafluoroethylene) (ETFE) films has been extensively investigated. However, the microstructure and molecular changes of the film under different irradiation conditions are less wellunderstood. In this study, microstructure and molecular changes in ETFE films induced by gamma and electron irradiation with doses of 0-800 kGy are investigated using FTIR, UV-Vis, XRD, contact angle, SEM, and AFM measurements. The irradiated ETFE films show a linear dose-response relation in the dose range of 50-400 kGy. In particular, in the low doses of 50-150 kGy, the crystallization in the irradiated amorphous regions and the partial degradation of inherent crystalline layers are observed. In the irradiation doses higher than 150 kGy, the degradation of newly generated crystalline areas and the recrystallization of disordering regions take place. Moreover, the microstructure alterations occur within the bulk and at the surface of the irradiated films. The 2-year shelf-aged films exhibit the partial preservation of chemical structures with the low oxidation effects, plus the features of linear dose-response with doses of 50-400 kGy. The obtained results provide a further understanding of radiation-induced effects in the ETFE films, which is the basic to extend their applications, especially in radiation resistance and dosimetry.

Electron-Induced Alteration of PLA Chain Structure

“…Some publications that involved polymer materials mainly discussed crystallization kinetics and crystallinity change . Some mechanisms of irradiation-induced crystallization have been presented for polymer materials based on tie-molecule breakup or chain scission. − However, no intuitive microscope picture, such as the polarized-light optical microscopy picture, was involved in these literature reports to illustrate the irradiation-induced morphology transition of the crystalline structure.…”