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Pitch-based carbon fiber (pitch-based carbon fiber, PCF) is recognized as a new type of high thermal conductivity of carbon fiber reinforced resin matrix composites used to prepare material can reach a higher thermal conductivity. However, the thermal conductivity of the resin matrix performance is not very satisfactory, and because the fiber and matrix compatibility issues, restrictions composite performance. Therefore, this thesis used carbon nanotubes (carbon nano-tubes, CNTs) and zinc oxide whisker (ZnOw) modified two kinds of resin matrix,epoxy (Epoxy, Ep) and CE (Cyanate Ester, CE), prepared the superior performance of carbon fiber reinforced resin matrix composites, for the composite application provides a theoretical basis and technical support.Using XRD, SEM, AFM, XPS, and other modern means analysis and testing the surface characteristics and structure of PCF. For the characteristics of PCF’s surface, this paper have studied on Ep resin and CE resin systems to match it.First selected a surfactant to disperse carbon nanotubes, modified the surface of zinc oxide whiskers, and determined the addition ratio of ZnOw/CNTs. Experiments showed that sodium dodecylbenzene sulfonate (DDBS) as the surfactant on carbon nanotubes in the dispersion of the resin matrix is better; using a silane coupling agent KH560modified zinc oxide whiskers can improve the thermal conductivity of the resin matrix performance; when carbon nanotubes with zinc oxide whisker ratio was4:1, the best thermal performance resin systems.Then separately investigated the amount of CNTs, CNTs/ZnOw mixed filler content on the Ep resin and CE resin thermal properties, mechanical properties, thermal properties. The results show that the hybrid method to modified the two resins matrix present the better performance; in Ep resin system, when the CNTs/ZnOw mixed filler content of6%, in the thermal conductivity coefficient which0.57W/K m, higher than the unmodified Ep resin matrix3.17-fold increase; in the CE resin system, when the CNTs/ZnOw mixed filler content of8%, the thermal coefficient of0.62W/K m, relative to the unmodified resin CE matrix2.38-fold increase; under these conditions, the two resin systems present optimal thermal performance. Meanwhile, the mechanical properties and thermal stability have also improved.Applying the above optimal modified resin systems to prepare pitch-based carbon fiber reinforced resin matrix composites, tested its thermal properties, mechanical properties, thermal properties. The results show that, Ep resin-based composite materials in CNTs/ZnOw mixed filler content of6%, the thermal conductivity reaches5.63W/K m, flexural strength reaches186MPa, thermal stability is also improved; CE resin-based composite materials in CNTs/ZnOw mixed filler content of8%, the thermal coefficient of8.48W/K m, the bending strength of209MPa, a significant improvement in thermal stability.
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