Preparation And Propeties Research Of Carbon Fiber Reinforced Polypropylene Composites

Owing to the many advantages of carbon fiber, such as its high specific modulus, high specific strength, high electric conductivity and corrosion resistance, low thermal expansion coefficient, carbon fiber reinforced composites have enormous application prospect, and have been used in a variety of applications such as aerospace and automobile industry and so on. A composite sheet with 1.5-2 mm in thickness made of carbon fiber felt and polypropylene is prepared in this paper, with superior strength and modulus compared with other fiber mat reinforced polypropylene.The carbon fiber reinforced polypropylene composites (CFRPP) were made by double belt press through melt-impregnation, and then molded by platen press. The preparation of CFRPP was optimized by studying the structure parameter such as carbon fiber length, fiber content, felt needling. The influence of film impregnation and mixed fiber felt impregnation to mechanical properties and porosity of CFRPP was studied. The influence of compatilizer MPP and VPP to the mechanical properties of CFRPP was studies and the optimum dosage of MPP was defined verified by the scanning electron microscope (SEM). The results revealed that, it had little influence on the mechanical properties within the experiment scope of the fiber length. The carbon fiber content of composites with optimum comprehensive mechanical properties was 30%wt. The mechanical properties of composites were improved greatly when the carbon fiber felt after triangle needle acupuncture. The interface bonding between carbon fiber and polypropylene was improved by compatilizer MPP so as to improve the mechanical properties of composite materials, and the optimum dosage of compatilizer MPP was about 20%wt. When the carbon fiber felt was made by triangle needling with fiber length of 80 mm, impregnated by polypropylene modified with MPP content of 20%wt, the mechanical properties of composites with fiber content of 30%wt were 203.3MPa of Tensile Strength,16.6GPa of Tensile Modulus, 223.2MPa of Flexural Strength,12.0GPa of Flexural Modulus and 752.2 J/m of Notched Impact Strength.Short carbon fiber/polypropylene granules were made by double-screw extruder, and prepared to simples by injection molding. The influence of compatilizer and carbon fiber content to mechanical properties of short carbon fiber reinforced polypropylene composites (SCFRPP) was studied, and the optimum dosage of MPP and carbon fiber was defined.