Property modification of SiR-EPDM blends by electron beam irradiation

Ethylene propylene diene monomer rubber (EPDM) is an excellent rubber for outdoor use. Silicone rubber (SiR) containing EPDM may show improved weathering resistance. Hence, EPDM is blended with silicone rubber with various blend ratios. After processing and curing, the electrical and mechanical properties of the SiR/EPDM blends are determined. The heat and weathering resistance of the SiR/EPDM blends were determined in terms of tensile properties of the blends with various blend ratios. The results of the experiments show that the tensile strength of the blends progressively decreased with an increased amount of SiR. The electrical properties decrease with the increase in EPDM content. E beam radiation is generally used to improve the performance of the polymeric materials. This paper discusses the resultant beneficial effects created by electron beam during the cable manufacturing process. This paper presents the results of investigations concerning the changes in mechanical and electrical properties of various blends of SiR/EPDM exposed to different doses of electron beam radiation. Samples were exposed to three different doses of e beam (5 Mrad, 15 Mrad, and 25 Mrad) and the various electrical and mechanical parameters are investigated. The electrical changes induced by irradiation are investigated by arc, surface, volume resistance and comparative tracking index measurements. Also the mechanical changes caused by e beam are analyzed by tensile strength and elongation at break measurements.