Irradiation energy response of the ac spectroscopy of ion-irradiated unplasticized PVC/Pva films

A study has been carried out to investigate the effects of irradiation energy and temperature on some physical properties of unplasticized poly (vinyl chloride)/ploy (Vinyl Alcohol) copolymers films. Films of the unplasticized PVC/Pva copolymer were irradiated with proton beams in the energy range 25-37 MeV and at a beam fluence of 0.225x1010 ion.cm-2. The induced changes in the ac conductivity and dielectric properties for he irradiated films compared with un-irradiated ones were studied, in the frequency range 2.5 khz-1 MHz and at elevated temperatures. It has been found that the ac conductivity frequencies. This is attributed to the dehydro chlorination (loss of HCl) by exposure to energetic particles. Obtained data revealed that ac conductivity is proportional to ωs for the un-irradiated and irradiated films. It has been also found that the value of σac increased linearly with increasing frequency, meanwhile the frequency exponent s decreased with increasing beam energy. In addition, for fixed beam energy of 37 MeV, s is increased from 0.47-0.68, in the temperature rang from 303 to 373 K