Study On Thermal Conductivity Of Epoxy Matrix Composites

With the development of electronic packaging technology,the miniaturization of electronic products has caused the heat accumulation of electronic products under high frequency work to be unable to dissipate in time,which limits the further development of electronic products.Epoxy resin is a commonly used electronic packaging material due to its low thermal conductivity and performance defects limit its application in the field of high-performance packaging.Therefore,the preparation of epoxy resin-based composite materials with high performance and high thermal conductivity is of great significance for the further development of electronic products.In this paper,silicone modified epoxy resin is used to improve the performance defects of epoxy resin,and a series of composite materials are prepared by adding Al₂O₃ and graphite as thermal conductive fillers.The main contents are as follows:The silicone modified epoxy resin is prepared by blending SH-023-7 and Dow 332epoxy resin.The thermal conductivity,DSC and TGA analysis of the material show that when the content of SH-023-7 is 15%,the maximum thermal conductivity of the modified resin is 0.25W/?m·K?.The addition of silicone reduces Tg and increases the thermal stability of epoxy resin at high temperatures.In this paper,dopamine surface-modified Al₂O₃ particles are blended with SEP resin to prepare thermal conductive composites.By characterizing the thermal conductivity,FTIR,XRD,SEM,etc.of the material,after dopamine modification,the dispersibility of Al₂O₃ in the resin matrix is improved,and the presence of polydopamine improves the compatibility of Al₂O₃ with the resin matrix and reduces the scattering of phonons at the interface and improves the thermal conductivity of the material.The addition of Al₂O₃ increases Tg and thermal stability of the material.Two-dimensional fillers are easier to construct a thermal network,and the interface thermal resistance of large-particle fillers is smaller.Graphite/SEP composites are prepared by using 16 mesh graphite as filler.Through the thermal conductivity,SEM and TGA analysis of the material,16-mesh graphite forms a good thermal conduction channel in the resin matrix,and improves the thermal conductivity of the material.When the graphite content is 60wt%,the thermal conductivity of the material reaches1.38W/?m·K?.Compared with Al₂O₃,it can effectively improve the thermal conductivity of the material and has better workability.The addition of graphite increases the decomposition temperature of the material and reduces the thermal weight loss of the material.Compared with Al₂O₃,it also has good thermal stability.In this paper,nano Fe₃O₄ is loaded on the graphite surface to prepare a magnetic field oriented graphite/SEP composite.It is shown by the analysis of SEM,XRD and thermal conductivity of the material.The graphite surface was successfully loaded with nano Fe₃O₄.Through the analysis of the cross-sectional morphology of the material,it can be found that the graphite is oriented in the direction of the magnetic field,which improves the thermal conductivity.XRD analysis of the orientation structure of the material shows that the graphite has been oriented in the resin.When the content of Fe₃O₄ is 0.4g,the relative graphite/nano Fe₃O₄ cotent is 200wt%,and the number of magnets is 3,the maximum thermal conductivity of the composite is 5.66W/?m·K?,it is 27 times of pure epoxy resin.