A Study On The Preparation And Properties Of High Thermal Conductive Composites

With the electronic technology toward miniaturization,portability and highly integration development,the internal heat of electronic devices is rapidly generated and accumulated at the high-power state,therefore,the stability and reliability of electronic device face a severe challenge.As a new generation of electrical packaging materials,composite materials with high thermal conductivity are important for heat dissipation of electronic devices.In this work,three kinds of high thermal conductivity composite materials were synthesized by using boron nitride and graphene as thermal conductive materials:Novel core-shell SiO₂@BN hybrids were synthesized via the high temperature calcinations method.Then,SiO₂@BN hybrids were used to prepare epoxy composites.SiO₂ as the inner hard template carry a thin layer of BN,which effectively solves the agglomeration problem of BN and significantly improves the thermal mechanical properties of composite materials.Additionally,the BN layer can construct thermal conductive pathways,so the thermal conductivity of epoxy composites is significantly enhanced;Special structured h-BN/Ag NPs hybrids were prepared via the electrostatic assembly method and redox method.Then,h-BN/Ag NPs hybrids were used to fabricate epoxy composites.The PEI coating enhances the interface effect between the filler and epoxy to achieve the uniform dispersion.In addition,Ag NPs serve as a bridge between the h-BN layers to achieve a more complete thermal conductive network in the epoxy resin and thus enhance the thermal conductivity of epoxy composites;RGO-PDA films were successfully prepared via layer-by-layer self-assembly method and high pressure tablet method.GO is greatly reduced in the self-polymerization process of DA.Meanwhile,PDA molecules are grafted between the RGO sheets to construct thermal conductive pathways to improve the thermal conductivity and electrical properties of RGO-PDA films.