液晶功能化氮化硼/液晶环氧树脂导热复合材料的制备  

Liquid Crystal Functionalized Boron Nitride Fillers/Liquid Crystal Epoxy Thermally Conductive Composites

作　　者：顾军渭 程蓓[1,2] 杨旭彤 GU Jun-Wei;CHENG Bei;YANG Xu-Tong(Research&Development Institute of Northwestern Polytechnical University in Shenzhen,Shenzhen 518057,China;School of Chemistry and Chemical Engineering,Northwestern Polytechnical University,Xi'an 710072,China)

机构地区：[1]西北工业大学深圳研究院,深圳518057 [2]西北工业大学化学与化工学院,西安710072

出　　处：《应用化学》2021年第10期1382-1388,共7页Chinese Journal of Applied Chemistry

基　　金：广东省基础与应用基础研究基金(No.2019B1515120093);国家自然科学基金(Nos.51773169,51973173);陕西省自然科学基础计划杰出青年基金(2019JC-11);大学生创新创业训练计划项目(S202010699003)资助。

摘　　要：导热高分子复合材料的导热系数(λ)难以达到预期值的重要原因之一在于高分子基体的本征λ低;同时导热填料-高分子基体的界面热障也是导致其导热性能提升不佳的重要因素。通过在球形氮化硼(GBN-100)表面原位接枝液晶环氧小分子(LCE-g-(GBN-100),gGBN-100),再与自制的主链型液晶环氧树脂(M-LCER)基体熔融共混复合-浇注成型制备gGBN-100/M-LCER导热复合材料。结果表明,GBN-100表面LCE的引入赋予了gGBN-100液晶特性,同时有效降低了gGBN-100和M-LCER基体的界面热障。当gGBN-100的质量分数为30%时,gGBN-100/M-LCER导热复合材料的λ为1.12 W/mK,为纯M-LCER基体λ(0.51 W/mK)的2.2倍,也高于相同用量(质量分数30%)下GBN-100/M-LCER导热复合材料的λ(1.02 W/mK)。此时gGBN-100/M-LCER导热复合材料的弹性模量和硬度也从纯M-LCER基体的2.78和0.19 GPa分别提高到4.13和0.24 GPa。The thermal conductivity coefficient(λ)of thermally conductive polymer composites is difficult to reach the expected value due to the intrinsic lowλvalue of polymer matrix.Meanwhile,the interfacial thermal resistance between thermally conductive fillers and polymer matrix is also another important factor leading to the poor thermal conductivity.In this work,liquid crystal epoxy molecules are in-situ grafted on globular boron nitride(LCE-g-(GBN-100),gGBN-100)fillers,which are melt-blended with main-chain liquid crystal epoxy resin(M-LCER)to fabricate the gGBN-100/M-LCER thermally conductive composites.Results show that the introduction of LCE on the surface of GBN-100 endows the liquid crystal properties of gGBN-100 fillers,and effectively reduces the interfacial thermal resistance between gGBN-100 fillers and M-LCER matrix.When the mass fraction of gGBN-100 fillers is 30%,theλof gGBN-100/M-LCER thermally conductive composites is 1.12 W/mK,which is 2.2 times of that of pure M-LCER matrix(λof 0.51 W/mK)and also higher than those of 30%GBN-100/M-LCER thermally conductive composites(λof 1.02 W/mK).At this time,the corresponding elastic modulus and hardness of gGBN-100/M-LCER composites increase from 2.78 GPa and 0.19 GPa to 4.13 GPa and 0.24 GPa,respectively.

关 键 词：液晶环氧树脂 液晶功能化 球形氮化硼 导热复合材料 界面热障 

分 类 号：O632.7[理学—高分子化学]