Preparation And Properties Research On Composites Made Of Resins Reinforced By Carbon Fiber

Polypropylene composites reinforced by MH300 carbon fiber or Toray carbon fiber were prepared, and their antistatic and mechanical properties were studied. Based on this and combined with scanning electron micrograph of the composite cross-section,further study has been done to reveal how does molding process, the performance of carbon fiber and carbon fiber surface treatment effect the tensile strength and tensile modulus of composites.It’s found that when MH300 carbon fiber content reaches or exceeds 10wt% or Toray carbon fiber content reaches or exceeds 12 wt%,the electrical conductivity is greater than 10-7S/cm,which can meet the antistatic requirements.The tensile strength and tensile modulus of CF/PP composites prepared by Using Haake mixing-CF injection molding process are higher than by molding process. Without surface treated, MH300 carbon fiber does better on reinforcing polypropylene than Toray carbon fiber.Through studing morphology of carbon fiber, we found that MH300 carbon fiber’s surface rougher and has more grooves so that more easily bonded to polypropylene.Besides, MH300 Carbon Fiber is thiner than Toray carbon fiber,which can help crystal nucleating on carbon fiber and is beneficial to the orientation in the molding process.After surface treated by strong acid, Toray carbon fiber’s reinforcing effect was significantly enhanced, but MH300CF/PP composites’tensile strength decreased, tensile modulus was unstable, that’s to say, strong acid surface treatment under the condition we adopted is not suitable for MH300 carbon fiber.The VRTM molding process for CF/EP composites’preparation were also studied, specifically studied the suitable molding process conditions for LT5078 epoxy system and E-51 Epoxy system. Combined with scanning electron microscopy,the appearance and mechanical properties of the two composites were compared and confirmed that smooth and mechanical properties of the composites were directly affected by infiltration between epoxy and carbon fiber.The results showed that, LT5078 epoxy system has low viscosity compared to E-51 epoxy system,and can achieve a better filling at room temperature to prepare composites with excellent mechanical properties, while E-51 epoxy system needs to be heated to about 65 ℃. Therefore, LT5078 epoxy system is significantly more suitable for the preparation of CF/EP composites in this study.