3D Lamellar-Structured Graphene Aerogels for Thermal Interface Composites with High Through-Plane Thermal Conductivity and Fracture Toughness  

作　　者：Pengfei Liu Xiaofeng Li Peng Min Xiyuan Chang Chao Shu Yun Ding Zhong-Zhen Yu 

机构地区：[1]Beijing Key Laboratory of Advanced Functional Polymer Composites,Beijing University of Chemical Technology,Beijing 100029,People’s Republic of China [2]State Key Laboratory of Organic-Inorganic Composites,College of Materials Science and Engineering,Beijing University of Chemical Technology,Beijing 100029,People’s Republic of China [3]Beijing Advanced Innovation Center for Soft Matter Science and Engineering,Beijing University of Chemical Technology,Beijing 100029,People’s Republic of China

出　　处：《Nano-Micro Letters》2021年第2期13-27,共15页纳微快报（英文版）

基　　金：Financial support from the National Natural Science Foundation of China(51773008,51533001,U1905217);the National Key Research and Development Program of China(2016YFC0801302)is gratefully acknowledged.

摘　　要：Although thermally conductive graphene sheets are efficient in enhancing in-plane thermal conductivities of polymers,the resulting nanocomposites usually exhibit low through-plane thermal conductivities,limiting their application as thermal interface materials.Herein,lamellarstructured polyamic acid salt/graphene oxide(PAAS/GO)hybrid aerogels are constructed by bidirectional freezing of PAAS/GO suspension followed by lyophilization.Subsequently,PAAS monomers are polymerized to polyimide(PI),while GO is converted to thermally reduced graphene oxide(RGO)during thermal annealing at 300℃.Final graphitization at 2800℃ converts PI to graphitized carbon with the inductive effect of RGO,and simultaneously,RGO is thermally reduced and healed to high-quality graphene.Consequently,lamellar-structured graphene aerogels with superior through-plane thermal conduction capacity are fabricated for the first time,and its superior through-plane thermal conduction capacity results from its vertically aligned and closely stacked high-quality graphene lamellae.After vacuum-assisted impregnation with epoxy,the resultant epoxy composite with 2.30 vol% of graphene exhibits an outstanding through-plane thermal conductivity of as high as 20.0 W m^−1 K^−1,100 times of that of epoxy,with a record-high specific thermal conductivity enhancement of 4310%.Furthermore,the lamellar-structured graphene aerogel endows epoxy with a high fracture toughness,~1.71 times of that of epoxy.

关 键 词：Anisotropic aerogels GRAPHENE Thermal conductivity Epoxy composites Fracture toughness 

分 类 号：TB332[一般工业技术—材料科学与工程]