Effect of eta- and γ-radiation on molecular-mass and dielectric characteristics of PE and RS

Effect of n-, γ-radiation upon fraction composition, molecular mass, molecular-mass distribution, electric strength and dielectric loss tangent of industrial samples of low-pressure polyethylene (PE) and impact-resistant polystyrene (PS) is studied. The irradiation has been performed with the doses: 2500 Gy, 0.01, 0.1 and 1.0 MGy. All the samples at first have been irradiated with 2500 Gy neutrons and then with γ-quanta up to the doses 0.01, 0.1 and 1.0 MGy respectively. It is shown that under the radiation effect the fraction composition of polymer changes both in the range of low-molecular and high-molecular fractions. After the effect of the 1 MGy dose the polymer transforms into unsoluble fraction (gel) in the quantity of 76%. During polysteryne irradiation decomposition of macromolecules is accelerated in contrast to PE. Dielectric characteristics of PE and PS samples during irradiation change differently. Dielectric losses of the PE samples change more considerably especially at doses of 1 MGy. The curves of PE and PS electric strength dependence on the irradiation dose testify to the difference of molecular-structural transformations taking place during irradiation