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Because of their excellent chemical stability, good electrical insulating properties, low shrinkage after curing, easy molding and so on, the epoxy resin are widely used in many areas such as electronic device materials, engineering materials and composites. But in many applications, people hope that the epoxy resin do not only has excellent electrical insulation, but also have good thermal conductivity. But the thermal conductivity of the epoxy resin is not good, so we can use fillers, which have a high specific heat capacity, to synthesize EP-matrix composites. This method is economical and practical, also simple and easy to get, so be widely used.In this experiment, we used boron nitride (BN), aluminum nitride (A1N) as fillers added to the epoxy resin, prepared the thermal insulation composites with different filler content. At the same time, we used the scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, thermal conductivity meter, integrated thermal analyzer tool to test the composite materials, to study the morphology of different filler content, crystal in this experiment, has used boron nitride, aluminum nitride as a filler added to the epoxy resin, was prepared by thermal insulation composites with different filler content of the two series. At the same time, the use of scanning electron microscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy, thermal conductivity meter, integrated thermal analyzer tool for testing composite materials obtained to study the morphology of different filler content, crystal structure, the functional groups and so on.When BN was used as filler, the thermal conductivity of EP/BN composites rise with the increase of filler content. When the filler content is40%, the thermal conductivity of the composite reach1.284W/(m-K), and still maintain good insulation properties. By SEM, XRD and infrared light analysis, we found that the binding property is great between the filler and matrix. The tests showed that the material can meet the requirements of practical applications, and thermal stability is excellent.For EP/A1N composite material, its thermal conductivity is still very satisfactory. Its thermal conductivity is1.18W/(m-K) with the filler content of60%. Moreover, further analysis by morphology analysis, XRD, infrared and other tests found that the material EP matrix pack the powder effectively, the formation of network structure can achieve the purposes of the heat conduction, stress transfer and absorbing heat.The role of the modifier in the preparation process of the composite can be found by farther studying, the modifier can reduce the surface energy of the filler particles, can promote decentralization and prevent the reunion. In addition, the modifier will enhance the compatibility of the BN, AIN particles and EP matrix, to improve the EP/BN, EP/AIN composite various aspects of performance.
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