α-Al_(2)O_(3)/XLPE接地线绝缘材料的制备及性能分析  

Preparation and Performance Analysis ofα-Al_(2)O_(3)/XLPE Grounding Wire Insulation Materials

作　　者：郭兴源 陈晓彬 林旭毅 姚迪吉 林弘 黄毓琦 GUO Xingyuan;CHEN Xiaobin;LIN Xuyi;YAO Diji;LIN Hong;HUANG Yuqi(Jieyang Power Supply Bureau,Guangdong Power Grid Co.,Ltd.,Jieyang 522000,China)

机构地区：[1]广东电网有限责任公司揭阳供电局,广东揭阳522000

出　　处：《塑料科技》2025年第2期26-31,共6页Plastics Science and Technology

基　　金：南方电网公司科技项目资助(035200KC23070004)。

摘　　要：采用熔盐法制备α-Al_(2)O_(3),采用硅烷偶联剂γ-氨丙基三乙氧基硅烷(KH550)对α-Al_(2)O_(3)进行表面改性,得到KH-α-Al_(2)O_(3)。以低密度聚乙烯(LDPE)为基体、不同的α-Al_(2)O_(3)为添加剂,制备α-Al_(2)O_(3)/XLPE和KH-α-Al_(2)O_(3)/XLPE接地线绝缘材料。对α-Al_(2)O_(3)和KH-α-Al_(2)O_(3)的晶体结构、微观结构以及基团进行分析,考察不同α-Al_(2)O_(3)含量对α-Al_(2)O_(3)/XLPE接地线绝缘材料电学性能和热学性能的影响。结果表明:熔盐法制备的α-Al_(2)O_(3)是具有六方结构、结晶度高、直径5~10μm的不规则圆片,KH550的改性不会造成α-Al_(2)O_(3)结晶度的变化。KH-α-Al_(2)O_(3)在KH-α-Al_(2)O_(3)/XLPE接地线绝缘材料中沿材料厚度方向排列,且分散更为均匀,有利于抑制电荷在基体中的传输。KH-α-Al_(2)O_(3)有利于提高XLPE的直流击穿场强和直流电导率。当KH-α-Al_(2)O_(3)的添加质量分数为1.5%时,KH-α-Al_(2)O_(3)/XLPE的直流击穿场强达到320 k V/mm,电导率为1.043×10^(-13)S/m。KH-α-Al_(2)O_(3)的引入使XLPE基体和KH-α-Al_(2)O_(3)之间的界面产生一定数量的陷阱,有效实现了对注入电荷的抑制。KH-α-Al_(2)O_(3)可以明显降低XLPE的热失重速率,提高KH-α-Al_(2)O_(3)/XLPE接地线绝缘材料热稳定性。当KH-α-Al_(2)O_(3)的质量分数达到1.5%时,分解温度升高至475.44℃,90℃条件下的导热系数从0.390 W/(m·K)增加到0.545 W/(m·K)。α-Al_(2)O_(3)was prepared using the molten salt method,and its surface was modified with the silane coupling agentγ-aminopropyltriethoxysilane(KH550),resulting in KH-α-Al_(2)O_(3).Using low-density polyethylene(LDPE)as the matrix and differentα-Al_(2)O_(3)as additives,grounding wire insulation materials ofα-Al_(2)O_(3)/XLPE and KH-α-Al_(2)O_(3)/XLPE were prepared.The crystal structure,microstructure,and functional groups ofα-Al_(2)O_(3)and KH-α-Al_(2)O_(3)were analyzed,and the effects of differentα-Al_(2)O_(3)contents on the electrical and thermal properties ofα-Al_(2)O_(3)/XLPE grounding wire insulation materials were investigated.The results show that theα-Al_(2)O_(3)prepared by the molten salt method has a hexagonal structure,high crystallinity,and is an irregular disc with a diameter of 5~10μm.The modification with KH550 does not alter the crystallinity ofα-Al_(2)O_(3).In the KH-α-Al_(2)O_(3)/XLPE grounding wire insulation material,KH-α-Al_(2)O_(3)is aligned along the thickness direction of the material and is more uniformly dispersed,which is beneficial for suppressing charge transport within the matrix.KH-α-Al_(2)O_(3)enhances the DC breakdown strength and DC conductivity of XLPE.When the mass fraction of KH-α-Al_(2)O_(3)is 1.5%,the DC breakdown strength of KH-α-Al_(2)O_(3)/XLPE reaches 320 kV/mm,and the conductivity is 1.043×10^(-13)S/m.The introduction of KH-α-Al_(2)O_(3)creates a certain number of traps at the interface between the XLPE matrix and KH-α-Al_(2)O_(3),and effectively suppresses the injection of charges.KH-α-Al_(2)O_(3)significantly reduces the thermal degradation rate of XLPE and improves the thermal stability of the KH-α-Al_(2)O_(3)/XLPE grounding wire insulation material.When the mass fraction of KH-α-Al_(2)O_(3)reaches 1.5%,the decomposition temperature increases to 475.44℃,and the thermal conductivity under 90℃conditions increases from 0.390 W/(m·K)to 0.545 W/(m·K).

关 键 词：α-Al_(2)O_(3)/XLPE 接地线 绝缘材料 击穿场强 空间电荷 

分 类 号：TM21[一般工业技术—材料科学与工程]