Study On The Papermaking Process Of Carbon Fiber Reinforced Thermoplastic Composite

Carbon fiber reinforced thermoplastic composite(CFRTP)has the advantages of good processing performance,high specific strength and low density.It is a type of composite material that has been widely concerned at present.Wet papermaking technology combined with hot compression molding(papermaking/hot compression molding)process to prepare chopped carbon fiber reinforced thermoplastic composites(CCFRTP)is an efficient preparation process,which helps to improve the dispersion of fibers in the resin matrix,It helps to control the orientation distribution of fibers in the matrix.In this paper,carbon fibers and thermoplastic fibers are used as raw materials to study the dispersion properties of fibers in water.Computer software is used to simulate the effects of carbon fiber content,aspect ratio and orientation distribution on composite materials,and the resistance of carbon fiber reinforced polypropylene materials to the addition of lignin Effects of thermal oxygen aging.Carbon fibers(CFs)were studied using different types of dispersants and dispersion systems,including carboxymethyl cellulose(CMC),polyethylene oxide(PEO),polyether,anionic polyacrylamide(APAM),and polyether/APAM systems,Polypropylene fibers(PPFs),polyester fibers(PETFs)dispersion in aqueous solution.Experiments show that the polyether/APAM compound dispersion system can effectively improve the dispersion of carbon fiber,polypropylene fiber and polyester fiber in aqueous,and the optimal compound concentration of polyether and APAM is 50mg/1 and 10mg/L,respectively.Further study on the wettability of the polyether/APAM dispersion system on the surface of the fiber and found that the polyether and APAM and its mixed dispersion system has a strong surface wetting ability on the polyester fiber and nylon 66 fiber.The Digimat software package was used to establish an equivalent volume unit(RVE)for carbon fiber reinforced polypropylene(CF/PP)composites prepared by the papermaking/hot compression molding process,and the influence of carbon fiber content,aspect ratio and fiber orientation in the matrix on the mechanical properties,thermal conductivity and electrical conductivity of composite materials were studied.The simulation results showed that the carbon fiber content increased from 5wt%to 30wt%,and the elastic modulus,thermal conductivity and electrical conductivity of the composite increased by 290%,28%and 750%,respectively.The fiber length-to-diameter ratio increased from 100 to 700,and the electrical conductivity of the composite increased by about 5400%,but the changes in elastic modulus and thermal conductivity were small.Combined with the characteristics of the manual papermaking process,the change in fiber orientation tensor has little effect on the elastic modulus and thermal conductivity of the composite RVE.The orientation tensor increases from 0.485 to 0.495 in the x-axis direction,and the electrical conductivity increases in this direction by 27.7%.The dynamic oxidation induction time of CF/PP composites containing lignin is lower than that of samples without lignin,and with the increase of lignin content,the oxidation induction time of composites decreases,indicating that the addition of lignin leads to the resistance of CF/PP composites.Reduction of thermal oxygen aging ability.The samples with 2%lignin had the highest tensile strength retention rate before and after the thermal oxidation experiment,up to 84.6%.However,the tensile strength retention rate of the 1%lignin sample before and after the thermal oxidation test(69.1%)was lower than that of the sample without lignin addition(72.7%).Studying the dispersion of carbon fibers and thermoplastic fibers can help improve production efficiency,reduce fiber length damage caused by mechanical agitation,and help develop papermaking/hot compression molding processes to prepare CCFRTP.The computer software simulates the performance of CF/PP composite materials prepared by papermaking/hot compression molding,which helps to improve the speed of research and development,and provides assistance for the development of other preparation methods of CCFRTP.Studying the influence of lignin on CF/PP composites' heat-resistant oxygen aging will help developers use lignin to reduce the characteristics of CF/PP composites' heat-resistant oxygen aging,further design experiments to improve lignin's performance in the plastics industry application.