Study On The Preparationof Carbon Fiber Reinforced Thermoplastic Composites By Papermaking Method

Carbon fiber reinforced thermoplastic composites(CFRTP)have been developed rapidly as a kind of composites with broad market prospects,because their characteristics of light weight and high strength.Carbon fiber reinforced thermoplastic composites have low density,high specific strength and specific stiffness,excellent mechanical properties,corrosion resistance,heat resistance and impact toughness,etc.,at the same time,they are easy to recycle and have high utilization rates.They are ideal lightweight materials.The process period for preparing the carbon fiber reinforced thermoplastic composites by the papermaking method is short,the preparation process is simple,and the large-scale continuous production requirements can be better met.This paper studies the preparation of carbon fiber reinforced thermoplastic composites with chopped carbon fiber as the reinforcement and polypropylene(PP)fiber as the matrix,using the wet papermaking process.Through orthogonal experiments,the effects of carbon fiber content,carbon fiber length,hot pressing temperature and hot pressing time on the mechanical properties of composite materials were discussed.The results show that the carbon fiber content is the main factor affecting the mechanical properties of the composite material;under the test conditions,when the carbon fiber content is 20%,the carbon fiber length is 5 mm,the hot pressing temperature is 190?,and the hot pressing time is 10 min,the performance of the composite is the best.The tensile strength is 83.9 MPa,the bending strength is 52.5MPa,and the notched impact toughness is 48.2 k J·m^-2.This paper explored the influence of different carbon fiber ratios on the mechanical properties of CFRTP through a single element experiment.The test showed that,on the basis of other conditions unchanged,the proportion of carbon fiber increases,the tensile strength,bending strength and notched impact toughness of CFRTP all increase first and then decrease;when the carbon fiber content reached at 20%,the tensile strength?flexural strength and notched impact toughness of CFRTP all reach the maximum.At the same time,its density is up to0.98g·cm^-3when the carbon fiber content is 20%,achieving the purpose of lightening.In this paper,under better technological conditions,by adding different functional fibers to synergistically enhance CFRTP,the effects of glass fiber,aramid pulp and cellulose nanofibers on the mechanical properties of CFRTP are respectively explored.The results show that under the test conditions,when the glass fiber content and the aramid pulp content are 10%respectively,the tensile strength,flexural strength and notched impact toughness of CFRTP all reach the maximum,and the tensile strength is higher than that obtained by the same process,the tensile strength increased by 15.7%and 12.7%,bending strength increased by 18.6%and 15.8%,notch impact toughness increased by10.7%and 8.4%;The tensile strength of the nanocellulose/carbon fiber/polypropylene composite material reaches its maximum when the content of nanocellulose is 15%,the tensile strength is increased by60.4%,the bending strength is increased by 74.5%,and the notched impact toughness is increased by 60.9%.Experiments show that the addition of nano cellulose makes the mechanical properties of carbon fiber reinforced thermoplastic composites more greatly improved.By scanning and analyzing the handsheets of different fiber materials/carbon fiber/polypropylene composite materials,it can be concluded that when nanocellulose is added,an effective combination of carbon fiber and polypropylene fiber is formed,which greatly improves the composite material's performance.Mechanical properties.