Investigation on the Crystallinity of Crosslinked Polyethylene

High voltage AC/DC cables require thicker insulation to ensure excellent insulation performance. Selecting the appropriate crosslinker to design the crosslink and crystalline structure of XLPE is key to the insulating properties. Although the crystallinity of XLPE has been extensively studied by using X-ray diffraction and differential scanning calorimeters, few researchers have designed in situ experiments to observe its structure. In this paper, we have created an in situ observational experiment to monitor the structural changes of XLPE insulation. XLPE formed by DTAP crosslinker produces lower gas byproducts, which can effectively reduce the degassing time and energy consumption. The test results and COMSOL simulations indicate that the XLPE formed by straight-chain alkane crosslinkers has better mechanical, thermal and electrical insulating properties than cyclic alkane crosslinkers. Our work is of great significance for selecting suitable crosslinker to control the structure of XLPE and determining the production conditions for high-voltage cables.