Application Of Three-dimensional Graphene Skeleton As Thermal Interface Materials

With the miniaturization of electronic equipment,equipment energy density increased,the equipment of the cooling effect thus became a key factor in the development of the electronics industry,and equipment heat dissipation effect is good or not is a very important part of the material,the interfacial heat transfer between the interface between the heat transfer and thus become a bottleneck of electronic equipment heat conduction.When two rough solid material contact with each other,they are the real contact area between each other is very few,the contact surface between the part of the remaining space will be filled by air,and air thermal conductivity(0.026 w/mk)which much lower than the average thermal conductivity of metal four orders of magnitude,so heat transfer through the air relative to the the actual heat transfer by contact point is almost negligible.From this point of view,to improve the thermal conductivity of the interface,we need to reduce the roughness of the thermal contact material.The thermal interface is placed between two complexes to improve the thermal conductivity of the interface.Thermal interface materials can effectively improve the effective contact area between interfaces by selecting materials that with high thermal conductivity and filling interfacial pores.Nowadays,the thermal conductivity of graphene(5300W/mK)is used as filler in polymer materials to prepare thermal interface materials.In this paper,graphene nanoparticles are used to form a variety of three-dimensional graphene skeletons and have been successfully prepared with high conductivity graphene/epoxy resin composites.The thermal properties of graphene/epoxy resin composites were systematically studied.Specific research contents include:Through a variety of analysis and testing methods,the graphene raw materials used in this paper are systematically characterized.Explore three form graphene three-dimensional skeleton method,including:(1)Through the preparation of different diameter size of graphene nano film,and according to certain proportion for hybrid structures,graphene three-dimensional pathways were set up,then composite it with epoxy resin,Finally the High thermal conductivity composite material was prepared;(2)Polyurethane cotton with the rules of long-short reticular structure which can be a template materials to build 3D graphene skeleton,then composite it with epoxy resin which could greatly improve the performance of thermal conductivity of the polymer materials;(3)Si02 nano ball which can in-situ growth of SiC nanowires in graphene surface,by using a high frequency heater,the formation of a 3D graphene heat conduction path was set up,eventually thermal interface materials which with high longitudinal heat conduction can be prepared.Through simulated conditions of high power density encapsulation,the graphene will get 3D composites as a cooling channel to obtaining temperature rising curve and infrared thermal images,it can be confirmed in this paper that the preparation of graphene three-dimensional composite materials can greatly enhance the performance of thermal conductivity of polymer base,in order to achieve good cooling effect.The high thermal conductivity of graphene composite materials prepared by this paper can effectively reduce the energy loss,improve the life of electronic products and reduce the cost of electricity.lt is expected to be widely used in electronic packaging and other fields.