Effects of γ-radiation on dielectric properties of LDPE Al2O3 nanocomposites

Until now several methods for processing and characterization have been tested, and some theories and models have been proposed for these materials having a huge nanofiller-polymer interface area which seems to be the main responsible for their unique properties. The accelerated testing by irradiation of LDPE has been extensively studied in order to assess optimized formulation. The present paper characterizes LDPE modified with Al2O3 nanoparticles. The dispersed nanofiller was added in various concentrations (2, 5 and 10 wt%). The accelerated aging under gamma-irradiation was accomplished for evaluation of material behavior to hard stressing environment. Dielectric properties (real part of the permittivity and tan delta) and oxidation resistance were discussed. An improvement of the dielectric losses is noticed for the tested nanocomposites at a radiation dose up to 20 kGy. The radiochemical stability studied by chemiluminescence provides satisfactory stability in the correlation with slight modification of basis polymer due to the inert feature of filler. (C) 2012 Elsevier Ltd. All rights reserved.