Research On Interface And Thermal Conductivity Of Epoxy Resin Filled With Al₂O₃by Modification

With the development of microelectronics packaging technology,the packaging materials needhigher thermal conductivity.Although epoxy resin has good mechanical properties,chemical stabilityand good electrical insulation performance, its thermal conductivity is very poor,therefore, theyneed to add fillers with high thermal conductivity, and usually add non-conducting ceramic fillers inorder to guarantee the electrical insulation of materials.In this paper,using Al₂O₃as the reinforcefiller,prepare ZnO@Al₂O₃core-shell structure by surface modification,measure the interfacebonding strength of ZnO@Al₂O₃/epoxy resin composite materials, and analysis the effect ofinterface bonding strength on composite materials thermal performance.In this paper,sol-gel andchemical bath deposition were used to modify surface of Al₂O₃.Appling XRD diffraction andscanning electron microscope for analyzing modified surface of Al₂O₃,and then add modifiedalumina filler to epoxy resin, finally achieved ZnO@Al₂O₃/epoxy resin compositematerial.Experimental results showed that:（1）Alumina were modified by sol-gel method,preparedthe ZnO@Al₂O₃core-shell structure.When the coating concentration is n_Al2O3:n_ZnO=5:1,and theprecursor heat treatment temperature is1200℃,the bonding strength of ZnO@Al₂O₃/epoxy resinwas the highest at present,and when the fillers were30vol%,the tensile strength of the compositereached38.41MPa,and the thermal conductivity was1.016W/m.K,compared with unmodifiedAl₂O₃/epoxy resin composites,tensile strength increased24.18%and thermal conductivity increased21.1%.（2）Al₂O₃was modified by chemical bath deposition,the ZnO@Al₂O₃core-shell structure wasnot perfected,and when they were added to epoxy resin,the thermal conductivity almost did notincrease compared with unmodified Al₂O₃/epoxy resin composites.In this paper, the thermal simulation of pouring sealant in the LED light application was alsostudied, the thermal simulation result showed that: the pouring has a great effect on the lifetime ofLED light, the higher the thermal conductivity of pouring sealant, the better the heat dissipation ofLED light, the longer the lifetime of LED light.