电工技术学报2025，Vol.40Issue(13)：4017-4031,15.DOI:10.19595/j.cnki.1000-6753.tces.240844
热氧老化对基于酯交换的可降解环氧树脂服役性能与降解特性的影响
The Effect of Thermo-Oxidative Aging on the Service Performance and Degradation Characteristics of Ester-Exchange-Based Degradable Epoxy Resin
摘要
Abstract
Epoxy resin is widely used in epoxy cast electrical equipment such as dry-type transformers and dry-type reactors due to its good mechanical strength,chemical corrosion resistance,and excellent electrical insulation performance.However,the irreversible cross-linking network formed after curing makes it difficult to degrade and recycle retired electrical equipment.Researchers have developed a series of biodegradable resins with high electrical thermal mechanical properties and degradation characteristics by introducing dynamic covalent bonds.However,epoxy electrical equipment such as dry-type transformers and dry-type reactors that operate in complex environments such as high temperature,high electric field,and mechanical vibration for a long time can experience performance degradation due to resin aging,which affects their service life.The changes in the cross-linking structure of epoxy resin caused by thermal oxidative aging may have a certain impact on the service performance and degradation recovery characteristics of degradable resins.This article used the ester exchange catalyst triethanolamine to construct a degradable epoxy resin system,and conducted accelerated thermal oxidative aging tests on it to analyze the effects of aging time and catalyst on the service performance and degradation characteristics of degradable epoxy resin. Firstly,this article used ester exchange catalyst triethanolamine to construct a degradable epoxy resin system,and used traditional non degradable epoxy resin as a reference to conduct thermal oxidative aging tests on resins with different triethanolamine contents at three temperatures of 180℃,200℃,and 220℃.Then,the performance changes of different resin systems after aging were studied through comprehensive analysis of electrical properties,thermogravimetric analysis,dynamic thermomechanical analysis,mechanical properties and microstructure analysis.The bending strength retention rate was used as an aging index to estimate the service life.Finally,this article also explored the influence of thermal oxidative aging on the degradation properties of degradable resins. From the experimental analysis,the following conclusions can be drawn:(1)The insulation and electrical performance of the degradable epoxy resin system after high-temperature aging is slightly worse than that of traditional resins,but the degradation rate of the insulation performance of degradable resins is slower than that of traditional resins under 200 ℃ and 220 ℃ conditions,with V-TEOA-0.05 maintaining better electrical performance.(2)The thermal stability of the degradable epoxy resin system is slightly inferior to traditional resins,but V-TEOA-0.05 has a higher storage modulus and a slightly lower glass transition temperature,and also exhibits good thermal properties.(3)As the aging temperature increases,the difference in flexural strength between degradable epoxy resin and traditional resin after aging gradually narrows,and remains basically unchanged after 49 days of aging at 220℃.The estimated lifespan of the V-TEOA-0.05 system shows a temperature index of 163.13℃,demonstrating excellent heat and oxygen aging resistance.(4)In the mixed solution of EG and TBD,the degradation rate of V-TEOA-0.05 sample decreases with increasing aging time,which may be related to the increase in resin crosslinking density,decrease in free volume,and decrease in ester bonds.关键词
热氧老化/环氧树脂/电气性能/力学性能/降解特性Key words
Thermo-oxidative aging/epoxy resins/electrical properties/mechanical properties/degradation properties分类
信息技术与安全科学引用本文复制引用
刘贺晨,江钰哲,刘云鹏,周松松,刘畅..热氧老化对基于酯交换的可降解环氧树脂服役性能与降解特性的影响[J].电工技术学报,2025,40(13):4017-4031,15.基金项目
国家自然科学基金(52377025)和中央高校基本科研业务费专项资金(20226934)资助项目. （52377025）
