Study of the optical properties of gamma irradiated high-density polyethylene

Abstract

The effect of gamma irradiation on the optical properties of high-density polyethylene (HDPE) films has been studied. The samples were irradiated with gamma rays to dose levels up to 700 kGy. UV–Vis spectrophotometry measurements were carried out for the unirradiated and gamma irradiated HDPE films. The optical parameters, namely maximum molar absorption coefficient (εmax), dipole strength (M), transition dipole moment (μ), dipole length (L), oscillator strength (F), energy gap (Eg) and activation energy (Ea), were determined as a function of the gamma dose. The obtained results show an increase in the values of εmax, M, μ, L and F with increasing irradiation dose. On the other hand, Eg and Ea were found to decrease as the dose increases. The oscillator strength and the energy gap show linear relations, with correlation coefficients more than 99%, as a function of the irradiated dose up to 600 kGy. Therefore, it is possible to use HDPE films as gamma dosimeters in the dose range from 0 to 600 kGy by means of the UV–Vis spectrophotometry technique.