Study on Thermal and Electrical Properties of Epoxy Resin chain extension for Basin-type insulators

摘要

Basin-type insulators are key insulating components of SF₆ gas insulated switchgear. Under the condition of over voltage, surface flashover easily occurs on such kind of insulator, which reduces the reliability of GIS equipment. The insulation performance of basin-type insulator depends on the overall performance of the epoxy resin/Al₂O₃ composite. In order to study effects of epoxy resin on the electrical and thermal properties of the basin-type insulator, this paper prepared epoxy resin chain extension from Diglycidyl ether of bis phenol A (DGEBP A) and methyl tetrahydrophthatic anhydride (Me-THPA).By preparing the epoxy resin /Al₂O₃ Composite insulating materials, the effects of chain extension product on the curing kinetics, the glass transition temperature, the electrical breakdown strength and the impact surface flashover voltage are studied. Research results show that, with the increasing of the mol ratio of Me-THPA to DGEBP A, the exothermic amount of epoxy composite insulation material decreases during the curing process. Compared to the unextended chain, the cured product after chain extension increases the glass transition temperature, electrical breakdown strength, and surface flashover voltage of the epoxy resin/Al₂O₃ composite.