Effect of Electric Irradiation on the Mechanical Properties of Polypropylene/Vapor Grown Carbon Fiber Composites Prepared by Melt Compounding

摘要

In this study, we discussed the effect of the electric irradiation on the properties of Polypropylene (PP)/Vapor-grown carbon fiber (VGCF) composites prepared by melt compounding using a twin-screw extruder. Ethylene-propylene random copolymer was included in PP. Graft copolymer of maleic anhydride of polypropylene (MA-PP) was employed as an additive agent. The Young's modulus of PP and PP/MA-PP increased with the irradiation dose. On the other hand, the increments of Young's modulus of PP/VGCF and PP/MA-PP/VGCF to irradiation dose were smaller than those of PP and PP/MA-PP. The effect of electric beam on the yield stress coincided to that of Young's modulus. According to the X-ray diffraction results, the crystallinity of PP is almost independent of electric irradiation. Thermal conductivity of the composites was also independent of the electric irradiation even if the thermal conductivity increased by adding of VGCF. It is clear that the dispersion and shape of VGCF would not be broken by the electric irradiation. We concluded that the Young's modulus could be increased with irradiation beam due to cross-linking of amorphous ethylene component and maleic anhydride component and the chemical reaction was inhibited with VGCF because the mobility of the amorphous chain could be constrained by VGCF.