低气压介质阻挡放电条件下纳米SiO_(2)表面氟化研究  

Research on Surface Fluorination of Nanosilica by Dielectric Barrier Discharge Under Low Pressure

作　　者：杨国清[1,2] 刘阳[2] 戚相成 王德意[1,2] 王闯 曾庆文 YANG Guoqing;LIU Yang;QI Xiangcheng;WANG Deyi;WANG Chuang;ZENG Qingwen(Xi'an Key Laboratory of Intelligent Energy,Xi'an University of Technology,Xi'an 710048,China;Department of Electrical Engineering,Xi'an University of Technology,Xi'an 710048,China)

机构地区：[1]西安理工大学智慧能源重点实验室,西安710048 [2]西安理工大学电气工程学院,西安710048

出　　处：《高电压技术》2021年第9期3144-3152,共9页High Voltage Engineering

基　　金：国家自然科学基金(51707155);西北旱区生态水利工程国家重点实验室基金(2016ZZKT-12)。

摘　　要：为改善纳米颗粒的团聚问题,有效提升复合材料的绝缘性能,首先对低气压下基于介质阻挡放电的纳米SiO_(2)表面氟化过程展开研究,重点讨论了SiO_(2)表面氟化过程及其主导放电条件。然后基于等离子体放电特性和发射光谱诊断,分析了CF4/N_(2)混合气体等离子体的放电及分布特性,并对表面氟化处理纳米SiO_(2)进行微观表征。最后初步分析了该氟化技术对环氧基体电气性能的影响。研究结果表明:气压为10~13.5 k Pa、电压为5~7 k V的CF4/N_(2)低温等离子体在放电空间内呈现均匀分布;研究范围内的CF4/N_(2)低温等离子体的电子温度最低为0.497 e V,可实现CF4中C—F断键,为SiO_(2)表面氟化创造条件;对纳米SiO_(2)进行10 min等离子体有效氟化,F元素质量分数达到10.05%,且以CF2主要形式存在;纳米SiO_(2)团聚现象得到有效改善,在环氧基体中的分散更加均匀。掺杂SiO_(2)质量分数为5%的氟化填料后,环氧树脂局放起始电压提升最明显,较同掺杂含量未氟化试样提高17.21%。结果证明等离子体填料氟化处理SiO_(2)填料的的可行性,为氟化改性纳米填料提供新的研究思路。To improve the agglomeration of nanoparticles and the insulation performance of composite materials,the fluorination process of nanosilica based on dielectric barrier discharge under low pressure was investigated,and the surface fluorination process of nanosilica and its dominant discharge condition were discussed emphatically.Based on the plasma discharge characteristics and emission spectrum diagnosis,the discharge and distribution characteristics of CF4/N_(2) plasma were analyzed,and the micro-characterization of fluorinated nanosilica was obtained.Finally,the effect of the fluorination technology on the electrical properties of epoxy matrix was analyzed.The experimental results indicate that the plasma of CF4/N_(2) with pressure of 10~13.5 k Pa and voltage of 5~7 kV is uniformly distributed in the discharge space;And the lowest electron temperature of the plasma is 0.497 eV,which can break the C—F bond and create conditions for the fluorination of nanosilica surface.After effective fluorination of nanosilica by plasma for 10 min,the content of fluorine reaches 10.05%,and the main existing mode of the fluorine element is CF2.After plasma fluorination,the agglomeration of nanosilica is effectively improved and the dispersion in epoxy matrix is more uniform.After doping with 5% fluorinated filler,the partial discharge initial voltage of epoxy resin will increase most significantly,which is 17.21%higher than unfluorinated sample with the same doping content.The results verify the feasibility of plasma filler fluorination for treating nanosilica filler and provide a novel research idea for fluorinated modified nano-fillers.

关 键 词：低气压 介质阻挡放电 发射光谱诊断 纳米SiO_(2) 表面氟化 

分 类 号：TM855[电气工程—高电压与绝缘技术]