Optical studies of pure and gelatin-doped poly(vinyl alcohol) films irradiated with fast neutrons

The ultraviolet (UV) and infrared (IR) spectra of pure poly(vinyl alcohol) (PVA) and gelatin-doped PVA films with concentrations (2, 5, 7, 10, and 15 wt %) were studied before and after irradiation with neutron fluences in th e range of 10(5)-10(8) n/cm(2). The obtained data revealed that the additio n of gelatin and neutron irradiation causes structural variation in the PVA network. The analysis of the UV spectra showed that the increase of dopant concentration above 5 wt % gelatin makes the sample less resistant to a de gradation effect caused by neutron irradiation. It was also found that the intensity of the band at 210 nm increases by increasing dopant concentratio n. Careful examination of the infrared spectra indicated that the induced p ercent crystallinity of the sample containing 5 wt % gelatin has more stabi lity than the other doped samples. Neutron irradiation also results in the appearance of new absorption bands and irregular change in the absorbance o f some IR bands. (C) 1999 John Wiley & Sons, Inc.