硅烷偶联剂改性TiO_(2)对植物绝缘油中水分子扩散行为影响的分子模拟研究  

Molecular simulation on effect of silane coupling agent modified TiO_(2)on water molecular diffusion behavior in vegetable insulating oil

作　　者：赵曼卿 王洋 李健飞 张仟凯 李华强[2] 朱庆东 ZHAO Manqing;WANG Yang;LI Jianfei;ZHANG Qiankai;LI Huaqiang;ZHU Qingdong(School of Electronics and Information,Xi′an Polytechnic University,Xi′an 710048,China;State Key Lab of Electrical Insulation and Power Equipment,Xi′an Jiaotong University,Xi′an 710049,China;State Grid Shandong Electric Power Company Electric Power Research Institute,Jinan 250001,China)

机构地区：[1]西安工程大学电子信息学院,陕西西安710048 [2]西安交通大学电力设备电气绝缘国家重点实验室,陕西西安710049 [3]国网山东省电力公司电力科学研究院,山东济南250001

出　　处：《绝缘材料》2023年第11期57-64,共8页Insulating Materials

基　　金：陕西省自然科学基础研究计划(2021JM-450);中国博士后科学基金资助项目(2019M653630)。

摘　　要：本文采用分子动力学模拟的方法建立了两种硅烷偶联剂(KH570、KH792)改性前后TiO_(2)/植物绝缘油界面结构的纳米分子模型,并进一步通过动力学仿真研究了硅烷偶联剂改性前后TiO_(2)界面对油中水分子扩散行为的影响。结果表明:相较于未处理的TiO_(2),改性后TiO_(2)界面对水分子有更强的吸附性,束缚了水分子在油中的扩散行为,致使其扩散系数显著降低,从而降低了油中水分子杂质形成“小桥”的概率,提升了植物绝缘油的绝缘性能,其中KH792的改性效果更为显著。进一步通过计算水分子与TiO_(2)界面体系相互作用能、形成氢键的数量和自由体积分数,解释了上述现象的成因与物理机制,为研究纳米粒子掺杂改善植物绝缘油绝缘性能提供了理论支撑。The nanomolecular model of TiO_(2)/vegetable oil interface structures before and after modification of two silane coupling agents(KH570 and KH792)were established by molecular dynamics simulation,and the effect of TiO_(2)interface before and after modification with silane coupling agents on the diffusion behavior of water molecules in oil were further investigated by dynamics simulation.The results show that compared with the untreated TiO_(2),the modified TiO_(2)interface has stronger adsorption of water molecules,which inhibits the migration behavior of water molecules in the oil,resulting in the significant reduction of their diffusion coefficient,thus reducing the formation of“small bridges”of water molecule impurities in the oil,and improving the insulating properties of vegetable insulating oil.Among them,the modification effect of KH792 is more significant.Further,by calculating the interaction energy between water molecules and TiO_(2)interface system,the number of hydrogen bonds form and the free volume fraction,the causes and physical mechanisms of above phenomena are explain,which provides theoretical support for the study of nanoparticle doping to improve the insulating properties of vegetable insulating oil.

关 键 词：植物绝缘油 纳米粒子 变压器 硅烷偶联剂 含水量 

分 类 号：TM214[一般工业技术—材料科学与工程]