Effects of Gamma Radiation on some physical Properties of Polystyrene / Polymetyl Methacrylate Polymer Blends

Abstract

In this study, Polystyrene (PS) and polymetyl methacrylate (PMMA)
blends were prepared by solution casting method with weight ratio (0, 5,
10, 15, 20 and 100 %) of PMMA in PS. The samples are then irradiated
using γ-rays with a radiation dose of 0.44 kGry and 1.76 kGry. The effects
of both PMMA concentration and gamma radiation on mechanical
properties (hardness) and dielectric properties of all samples were
investigated at room temperature. The study showed a decrease in the value
of hardness with increase in the weight ratio of PMMA in PS and when
irradiation with a dose of 1.76 kGry radiations and no change in the value
of hardness at the radiation dose 0.44 kGry for all samples. The study of
the dielectric properties (dielectric constant, dielectric loss and loss factor)
of the samples within the frequency range (100 Hz-10 MHz) showed an
increase in the values of dielectric constant, dielectric loss and loss
factor(tan) with increased PMMA concentration and decreased with
frequency increase for all samples before irradiation. After irradiation and
within the same concentration percentage, there was no change in the
dielectric properties at the radiation dose 0.44 kGry and improvement of
the dielectric properties at the dose of 1.76 kGry, where the results showed
a decrease in dielectric loss and loss factor and a small decrease in the
dielectric constant, Indicating the possibility of using these materials with
good dielectric properties in devices related to radiation.