EFFECTS OF X-RAY-RADIATION ON NAFION MEMBRANE

The effects of X-ray radiation on Nafion-117 membrane were investigate d by electron paramagnetic resonance spectroscopy (EPR), photoacoustic infrared spectroscopy (PAS), Raman scattering and ultraviolet-visible electronic absorption spectroscopy. EPR spectrum of irradiated Nafion membrane reveals the presence of peroxy free radical similar to that found in irradiated polytetrafluoroethylene. The Raman and infrared (I R) spectra of irradiated samples show the appearance of new bands at 1 458, 1700 and 1773 cm(-1), that can be associated with the presence of C = O and C = C groups. In addition, Raman and IR spectra show a band intensity change associated with the stretching modes of C-O, C-S and SO3-, indicating scissions of C-S and C-O bonds and SO2 liberation. U V-Vis spectra of irradiated samples exhibit bands at 196, 230 and 273 nm, whose intensities increase with irradiation doses and with aging t ime. (C) 1998 Elsevier Science Limited. All rights reserved.