Research Progress on Curing Regime Modulating Insulation Performances of Bisphenol-A Epoxy Resin/Anhydride System

doi:10.11985/2024.01.039

Abstract

Abstract:

Aanhydride cured bisphenol-A epoxy resin is widely used in the support, insulation and packaging and other key components of electrical equipment due to its excellent insulation, thermal and mechanical properties. However, under the condition of extreme environments and compact design, the epoxy resin insulation often suffers from overheating and breakdown faults, which seriously threaten the safe and stable operation of electrical equipment. The curing regime of epoxy resin system generally includes the combination of raw material mixing ratio, curing time and temperature, which is an important factor to determine the microstructure of epoxy resin and directly affects its macro performance. The evolution process of curing kinetic model of bisphenol-A epoxy resin cured by anhydride is introduced. It is verified by experiments that the curing process of bisphenol-A epoxy resin/anhydride system needs to consider the pre and post curing stages to fit its kinetic parameters. Based on different mixing ratios, curing time and temperature combinations, the influences of curing regime on the insulation performance of bisphenol-A epoxy resin/anhydride system were emphatically discussed. The regulation mechanism of the microstructure related to curing state on the insulation performance was discussed. The relevant research results are expected to provide reference for the application of high-end electrical and electronic epoxy resin in terms of formula selection and process optimization.

Key words: Bisphenol-A epoxy resin/anhydride system, curing regime, insulation performance, microstructure

CLC Number:

TM561

LI Jin, KONG Xiaoxiao, DU Boxue. Research Progress on Curing Regime Modulating Insulation Performances of Bisphenol-A Epoxy Resin/Anhydride System[J]. Journal of Electrical Engineering, 2024, 19(1): 358-370.

Figures/Tables 7

References 74

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分类	性能参数
高压电工装备用超高纯双酚A环氧树脂	环氧值(eq/100 g)：0.55~0.58；可水解氯(×10^-6)<300；氯离子(×10^-6)<5；黏度(mPa·s@25 ℃)<10 000
电工浇注环氧树脂(饱和电抗器)	环氧值(eq/100 g)：0.50~0.53；黏度(mPa·s@25 ℃)14 000~18 000
电工浸渍环氧树脂(绝缘拉杆/套管)	环氧值(eq/100 g)：0.58~0.60；黏度(mPa·s@25 ℃)900~1 200
电工浇注环氧树脂(高频变压器)	环氧值(eq/100 g)：0.50~0.53；黏度(mPa·s@25 ℃)10 000~15 000