复合绝缘子弱憎水性状态描述方法Ⅰ——静态接触角法的适用性  

Description Method Ⅰfor Unobvious Hydrophobic State of Composite Insulators——Usability of Contact Angle Method

作　　者：戴罕奇[1] 梅红伟[1] 王黎明[1] 赵晨龙[1] 贾志东[1] 关志成[1] 

机构地区：[1]清华大学深圳研究生院,深圳518055

出　　处：《电工技术学报》2013年第8期34-47,共14页Transactions of China Electrotechnical Society

基　　金：国家重点基础研究发展计划(973计划)(2009CB724503)资助项目

摘　　要：在高电压外绝缘领域,静态接触角法是实验室内研究硅橡胶绝缘材料憎水性能的最常用方法,在清洁材料表面且憎水性能优异时,该方法的有效性得到认可。本文主要探讨染污高温硫化硅橡胶(HTV)表面憎水性能较弱时,静态接触角法在此阶段研究污层憎水性能的适用性。弱憎水性状态体现了硅橡胶中小分子链的迁移过程,对应着污层从完全亲水性状态向憎水性状态转变时的过渡环节。本文通过对比研究不同体积、不同种类液滴在试片污层表面形态变化过程,结合复合绝缘子的人工污秽试验,尝试将污闪电压与污层表面憎水性能建立联系。研究发现:当污层憎水性能不够强时,受污层粗糙度、弱憎水性沿污层表面不均匀分布特征以及静态接触角测量方式的影响,获取代表试片整体憎水性能的接触角值变得困难。对于弱憎水性表面,静态接触角法不适用于污层表面憎水特性研究。Static contact angle is the most commonly used parameter in the laboratory for studying hydrophobic properties of silicone rubber. Usability of contact angle method has been proved on clean materials with good hydrophobicity. This paper aims to discuss the applicability of contact angle method on polluted high temperature vulcanizing silicone rubber（HTV） samples when the hydrophobicity is unobvious. Unobvious hydrophobic state reflects the migration process of low molecular weight components（LMW）, corresponding to the transitional period of dirty layer from absolutely hydrophilic state to strong hydrophobic state. To find building the link between hydrophobicity strength and flashover voltage, morphology change of different type and volume droplets on pollution layer were studied. As the following factors＇ function, such as the roughness of surface, uneven distribution of hydrophobicity on the surface and the way of measuring contact angle, it is difficult to obtain a valid contact angle to represent the hydrophobicity of whole surface when the hydrophobicity of pollution layer is unobvious. Contact angle method becomes no longer suitable for studying hydrophobicity properties when the hydrophobicity of pollution layer is unobvious

关 键 词：弱憎水性 接触角 硅橡胶 人工污秽 污闪电压 

分 类 号：TM21[一般工业技术—材料科学与工程]