摘要
研究了不同温度下天然酯-纸绝缘中绝缘纸聚合度下降速率、油中微水含量变化趋势,并与矿物油-纸绝缘的试验结果进行对比,初步分析了新型绝缘液体天然酯抑制绝缘纸老化的化学机制和物理机制。通过研究得出,老化温度每升高20℃,绝缘纸聚合度平均下降速率将变为原来的3～4倍;相同老化温度下,矿物油中绝缘纸聚合度平均下降速率是天然酯中绝缘纸聚合度平均下降速率的两倍多;天然酯能通过吸收水分、消耗水分和水解保护等方式减少绝缘纸中水分含量,减缓绝缘纸老化速度;天然酯中水分并不会无限增加,而是能够通过化学反应方式抑制自身水分增加;天然酯通过和纤维素分子中羟基发生酯交换反应抑制绝缘纸热应力下的水解作用。
The accelerated thermal experiments at the temperature of 90℃, 110℃ and 130℃ were performed, using the samples which were composed of mineral oil or nature ester with kraft paper, and the change of the paper degradation speed and water content were analyzed. The homology and the dissimilitude between them were researched. Meanwhile, the chemical and physical mechanism of the paper aging restrained by nature ester was studied as well. The results show that the degradation speed of the paper is four times when the aging temperature increasing every 20℃.The degradation speed of the paper in the mineral oil is two times more than the one in the nature ester at the same temperature.The nature ester can reduce the water content in the paper and restrain the degradation of the paper. The ester can restrain the increase of the water with chemistry reactivity. The esterification of the reactive OH sites in cellulose with bulky ester groups stabilizes the molecule and extends thermal life.
出处
《电工技术学报》
EI
CSCD
北大核心
2008年第9期32-37,44,共7页
Transactions of China Electrotechnical Society
基金
国家自然科学基金(50677073)
国家杰出青年科学基金(50425722)
重庆市自然科学基金重点资助项目(CSTC
2004BA6001)
关键词
天然酯
矿物油
降解速率
热老化
纤维素
Nature ester, mineral oil, degradation speed, thermal aging, cellulose
