基于液态金属/聚硫橡胶构筑兼具导热与自修复功能可拉伸热界面材料  

Stretchable Thermal Interface Material with Both Thermal Conduction and Self-Healing Functions Based on Liquid Metal/Polysulfide Rubber

作　　者：华琼瑶 于贵营 洪魏悠然 李春海[1] 郭少云[1] Qiongyao Hua;Guiying Yu;Weiyouran Hong;Chunhai Li;Shaoyun Guo(Polymer Research Institute,State Key Laboratory of Polymer Materials Engineering,Sichuan Provincial Engineering Laboratory of Plastic/Rubber Complex Processing Technology,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学高分子研究所,高分子材料工程国家重点实验室,四川省橡塑材料复合成型技术工程实验室,四川成都610065

出　　处：《高分子材料科学与工程》2021年第7期153-161,共9页Polymer Materials Science & Engineering

基　　金：四川省应用基础研究项目(重大前沿)(2018JY0548)。

摘　　要：针对导热自修复复合材料存在的自修复性能-导热性能-力学性能难以平衡的问题,利用液态金属(LM)作为导热填料,通过界面设计使LM与基体之间形成动态可逆配位键,提升复合材料导热性能的同时兼顾材料的力学性能和自修复性能。文中通过主链上含有大量二硫键(S-S)且以硫醇为端基(-SH)的液态聚硫橡胶(PSR)与液态金属(LM)共混复合,利用LM赋予复合材料较高热导率,借助PSR分子中的动态二硫键(S-S)及LM与PSR之间形成的金属-巯基、金属-硫自由基可逆配位键赋予材料自修复性能。研究表明,当LM的体积分数为50%时,复合材料导热率可达0.70 W/(m·K),是纯基体的4.17倍,断裂伸长率仍然高达525%,在90℃自修复4 h时,断裂伸长率修复效率达到98.3%,实现了材料自修复性能-导热性能-力学性能的平衡。To conquer the trade-off among the self-healing function-thermal conductivity-mechanical properties of the thermally conductive and self-healing composites,the liquid metal(LM)is chosen as thermally conductive filler,and a dynamic reversible coordination bond between the LM and the matrix is formed through the interface design,which not only improves the thermal conductivity of the composites,but also gives a better balance between the mechanical and self-healing properties.In this paper,a liquid polysulfide rubber(PSR)with a large number of disulfide bonds(S-S)on the main chains(-SH)and a mercaptan as end group(-SH)was blended with LM,the LM endows the composites with high thermal conductivity,while the dynamic reversible disulfide bonds(S-S)in the PSR molecules and the dynamic reversible coordination bonds between LM and PSR(metal-sulfhydryl,metal-sulfur radicals)give the composites self-healing functions.The experimental results show that when the LM volume fraction is 50%,the thermal conductivity of the composite can reach 0.70 W/(m·K),which is 4.17 times that of the pure matrix,and the elongation at break is still as high as 525%.At 90℃ for 4 h,the repair efficiency of the elongation at break can reach 98.3%,which achieves the balance of the self-healing functions,thermal conductivity,and mechanical properties.

关 键 词：自修复 导热 液态金属 聚硫橡胶 配位键 

分 类 号：TB333[一般工业技术—材料科学与工程]