Research on Aging Performance and Mechanism Analysis of Cross-linked Polyethylene Wire and Cable Materials

Cross-linked Polyethylene (XLPE) shows excellent insulation performance and heat resistance, resulted to widely using in various wire and cable materials. Due to the extensive using of XLPE, the anti-aging performance of XLPE has attracted a lot of attention. In this paper, the different effects of thermal aging and xenon lamp aging on the material surface are studied. Fourier Transform Infrared and Pyrolysis-Gas chromatography-mass spectrometry were used to analyze the aging mechanism of XLPE. Tensile test, Volume Resistivity test and Surface Resistivity test are used to evaluate the mechanical and electric properties, respectively. The results can be summarized as: (a) The volume resistivity of XLPE was still higher than 1014 Ω·M after 14 days of high temperature thermal aging. (b) The molecular chain broken of XLPE occurs on the surface first. (c) Xenon lamp aging results show that free radical reactions induced by light promote the degradation of XLPE. (d) After Xenon lamp aging, XLPE macromolecular chain break into relatively uniform small molecular alkanes. The results could provide practical and theoretical support for the production and application of XLPE.