X-ray irradiation-induced changes in Bayfol DPF 5023 polycarbonate

Abstract

Samples from sheets of the polymeric material Bayfol DPF 5023 have been exposed to X-ray radiation in the dose range 100-2300 Gy. The modifications induced in Bayfol samples due to X-ray irradiation have been studied through different characterization techniques such as X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, intrinsic viscosity, refractive index and color difference studies. The infrared spectroscopy indicated that crosslinking is the dominant mechanism at the dose range of 200-2300 Gy. The crosslinking reported by FTIR spectroscopy destroyed the degree of ordering in the Bayfol samples, as revealed by the XRD technique. Also, this crosslinking led to an increase in the value of intrinsic viscosity from 0.54 for the non-irradiated sample to 0.63 for the sample irradiated with 2300 Gy at 30 • C, indicating an increase in the average molecular mass. This was associated with an increase in the refractive index. Additionally, the non-irradiated Bayfol samples showed significant color sensitivity toward X-ray irradiation. This sensitivity appeared in the change of the blue color component of the nonirradiated Bayfol film to yellow after exposure to X-ray doses up to 2300 Gy. This is accompanied by a net increase in the darkness of the samples.