氟化协同高分子助剂调控环氧复合材料绝缘性能机制  

Insulation Performance Mechanism of Epoxy Composites Regulated by Fluorinated Synergistic Polymer Additives

作　　者：戚相成 同向前[1] 任鹏荣 杨国清[1] QI Xiangcheng;TONG Xiangqian;REN Pengrong;YANG Guoqing(Department of Electrical Engineering,Xi’an University of Technology,Xi’an 710048,China;School of Materials Science and Engineering,Xi’an University of Technology,Xi’an 710048,China)

机构地区：[1]西安理工大学电气工程学院,西安710048 [2]西安理工大学材料科学与工程学院,西安710048

出　　处：《高电压技术》2023年第11期4517-4526,共10页High Voltage Engineering

基　　金：国家自然科学基金(52272121,51972265);陕西省教育厅重点科学研究计划项目(20JS101)。

摘　　要：偶联剂作为常用小分子界面改性助剂,在等离子体作用下,其界面相容性易受影响。为进一步调控填料与环氧树脂基界面特性,采用端羧基超支化聚酯(carboxyl-terminated hyperbranched polyester,CHBP)对纳米SiO_(2)进行大分子链包覆,再协同等低温离子体对填料进行氟化接枝。对比分析不同改性方式下环氧复合材料化学组分、微观形貌、电荷特性及沿面闪络特性。实验结果表明:相比偶联剂预处理,经超支化表面接枝改性的纳米SiO_(2)与环氧基体间界面相容性更好,氟化协同改性后,其在基体内团聚尺寸较KH550/氟化改性显著减少。掺杂质量分数3%的CHBP/氟化改性填料,可有效减少高压电场下环氧复合材料的平均电荷密度,抑制空间电荷积聚及跨界面输运,其沿面闪络发展得到有效抑制,闪络电压分散性有所降低。其击穿场强最大值达到40.88 kV/mm,相较于同质量分数的CHBP改性,KH550/氟化改性试样分别提高了12.34%、20.13%。氟化协同高分子助剂接枝改性作为可行有效方法,为填料改性提供了新研究思路。As a commonly used low molecule interface modification agent,the interfacial compatibility of coupling agent is easily affected by plasma.To further improve the interface properties between fillers and epoxy resin,nanosilica is coated with macromolecular chains by carboxyl-terminated hyperbranched polyester.Then Fluorination Grafting of Fillers by Low-temperature ions.The chemical composition,microscopic morphology,charge characteristics and surface flashover characteristics of epoxy composites under different modification methods are tested and analyzed.The experimental results indicate that comparing with the coupling agent pretreatment,the nanosilica modified by hyperbranched surface grafting has a better interfacial compatibility with the epoxy matrix,and the agglomeration size in epoxy matrix is significantly reduced compared with KH550/fluorination modification.Doping 3%CHBP/fluorination modified fillers can effectively reduce the average charge density of epoxy composites under high-voltage electric field,and inhibit space charge accumulation and cross-interface transport.The flashover along the surface is effectively suppressed,and the dispersion of flashover voltage also reduced.The maximum value of the breakdown field strength reaches 40.88kV/mm,which is 12.34%and 20.13%higher than that of CHBP modified and KH550/fluorination modified samples with the same mass fraction,respectively.As a feasible and effective method,the grafting of fillers with fluorinated modified polymer additives provides a new research idea for filler modification.

关 键 词：超支化聚酯 等离子体氟化 界面改性 空间电荷 绝缘性能 

分 类 号：TM216[一般工业技术—材料科学与工程]