| With the miniaturization of electronic devices and the increasing of power,the density of dissipation power also increases rapidly,and the requirements for the electronic devices are also becoming higher and higher.Therefore,the researchers usually add some filler with high thermal conductivity into epoxy resin to prepare the thermal interface materials（TIMs）for improving the thermal conductivity of TIMs.Graphene has high thermal conductivity,which is often as thermal conductive fillers added to the epoxy resin.This kind of fillers has the very high electrical conductivity,and dispersed in the epoxy resin can increase the electrical conductivity of composite,produceing electron tunneling,which interferes the normal work of electronic device and causes electronic device failure.So this will not be conducive to the application of TIMs in the field of electronic packaging.In order to solve this problem,in this study,a series of thermal conductive fillers with low electrical conductivity and high thermal conductivity were prepared using high infrared radiation property of tourmaline and high thermal conductivity of Al（OH）3-coated graphene oxide.In this paper,a series of Al（OH）3-coated graphene oxide/tourmaline composites were prepared and characterized by X-ray diffractometer（XRD）,X-ray photoelectron spectrometer（XPS）,scanning electron microscope（SEM）,transmission electron microscopy（TEM）,and other means.First of all,graphene oxide（GO）was prepared by the modified Hummers method.Then the GO was coated by Al（OH）3 through sol-gel method.Finally,its and tourmaline compounded through hydrothermal method.The TIMs was prepared through dispersing the obtained composites into the epoxy resin,studying the effects of TIMs on thermal conductivity,electrical conductive and mechanical properties.In addition,the thermal conductivity model was established.Research results show that when the content of Al（OH）3-coated graphene oxide in fillers 15 wt%,the thermal conductivity of the epoxy resin composites has a maximum value of 0.5537 W/m·K.Compared to the pure epoxy resin（0.2291 W/m·K）,there is a increasing of 142%;The electrical conductivity of epoxy resin composites increases with the increasing of the content of GO or Al（OH）3-coated graphene oxide,and the electrical conductivity of epoxy resin composites with Al（OH）3-coated graphene oxide/tourmaline compounds has a maximum value of 1.24×10-5 S/m,lower than that of epoxy resin composites with GO/tourmaline compounds(2.34×10-5 S/m).Because Al（OH）3 layer formed on the surface of GO can block ion mobility as ion traps and prevent electron tunneling.Therefore,GO coated by Al（OH）3 layer can obviously reduce electrical conductivity of the composites.In addition,the mechanical properties of the composites were tested and compared.The results show that the addition of fillers with GO or Al（OH）3-coated graphene oxide have little effect on the mechanical properties of the epoxy resin matrix. |
