INVESTIGATION OF DIFFERENT CROSS-LINKING METHODS OF EOC:PDMS THERMOPLASTIC ELASTOMERS FOR CABLE INSULATION APPLICATION WITH SPECIAL REFERENCE TO THERMAL, RHEOLOGICAL, CREEP, AND ELECTRICAL PROPERTIES

Abstract

ABSTRACT This article demonstrates the influence of different cross-linking methods of the ethylene octene copolymer (EOC)–polydimethylsiloxane (PDMS) rubber blends. From rheology analysis, it is understood that the EOC with a high co-monomer content has better radiation cross-linkability as compared with the EOC with a low co-monomer content. Also, from the curing study using an oscillating die rheometer, it was found that as the octene content increases, the cross-linking efficiency of the peroxide to cross-link that particular EOC decreases. The tensile strength of the EOC2:PDMS blend with a high co-monomer content was drastically improved by 39% on irradiation with a dosage of 50 kGy, whereas for the EOC:PDMS blend with a low co-monomer content, the tensile strength was drastically improved by 60% on peroxide cross-linking. It is inferred that both the peroxide and radiation cross-linked blends show higher creep resistance compared with the neat blends. From the thermal studies, it was found that through blending and subsequent radiation cross-linking, the maximum degradation temperature of the high-octene-content EOC was increased from 480.5 °C to 509.1 °C. The cross-linked blends show higher-volume resistivity as compared with the un-cross-linked counterparts.