The Study Of Preparation And Properties Of Epoxy Resin With High Content Of Nano-Al₂O₃ Composites

In the field of electrical and electronic, application of the epoxy resin composite materials are electronic components with high density, high integration, both materials have good thermal conductivity, easy processing, and insulation, chemical corrosion resistance and other properties. The traditional thermal conductivity materials can not meet the requirements that the study of thermally conductive polymer composites are attentioned. The excellent performance of thermal conductive polymer composites not only have high polymer resin, but also improves the defects of the traditional polymer material thermal conductivity is deficiency. As the electronic, electric device voltage level and power level is requiremented to increase. There is excellent thermal conductivity, insulation epoxy resin composite material for electronic power device thermal and electrical aging lifetime extension that plays a more and more important roles.The surfaces of nano-Al2O3 particles were modified with coupling agent under ultrasonic shaking to prevent the agglomeration of nano-Al2O3 particles in resin matrix Bishenol A epoxy resin, amine agent and nano-alumina were blended in ultrasonic cell crusher. And then the well blended materals were cured in an ovent at 78 ?.The structure of the products was characterized by FT-IR,SEM, TG, DSC, DMA and universal testing machine. And the results showed that the modification of nano-scaled nano-almina particles has success synthesize testing. The nano-Al2O3/epoxy composite was more excellent in performance than epoxy resin. Section morphology showed that the blend is compatible and the thermal and mechanical properties increased with an increase of nano-alumina content. The temperatures of weight loss at 5 % and 10 % of nano-composites with 10 wt% nano-composites with 10 wt% nano-alumina were29.7 ? and 23.3 ? higher than that of pure epoxy resin repectively. And the storage modulus of nano-composites with 10 wt% nano-alumina was 40% higher than that of pure epoxy resin, while the loss modulus was 18.6% lower. The electric breakdown strength was 23.1 % higher than that of pure epoxy resin when the content of nano-alumina reached 5 wt%.The nano-alumina(nano-Al2O3) particles were modified by silicon couplingagent KH-560, and the epoxy matrix nano-composites were prepared by using nano-Al2O3 as reinforcing agent. Be prepared for 0%, 30%, 60% of casting epoxy resin and epoxy resin for 90% of molded composite materials. The dispersion status was studied by X-ray diffraction analysis(XRD). On this basis, effects of nano-Al2O3 content on dielectric and mechanical properties of the nano-composites were studied. Morphologies of the fracture surface of nano-Al2O3/epoxy composites were observed by scanning electron microscope(SEM). Both dielectric constant and dielectric loss of the composites show but sharp increase when the volume fraction 60% is above 14. Furthermore, the dependences of the dielectric constant and dielectric loss on frequency were also studied. With the increase of frequency from 1 x 107 Hz to 4 x 107 Hz, dielectric constant of the epoxy resin/nano-Al2O3 composites decreases, while the dielectric loss increases to 0.07 slightly. The results indicate that the epoxy resin/nano-Al2O3 composites are promising materials for capacitors.