Preparation Of Graphene Conductive Composite Fiber And Anlysis Of Its Structure And Properties

With the extensive use of electronic devices,charge accumulation becomes a serious problem as it would not only damage electronic instruments but also cause adverse effects on human health,even cause a fire.Much attention has been paid to solving this problem.Conductive fibers are designed and developed to eliminate charge accumulation in a short time through electron conduction and corona discharge.Conductive fabrics made of conductive fibers show excellent electronic conductivity,thermal conductivity and electromagnetic shielding,and thus find wide applications in medical,electronics,military and other fields.Graphene is a single layer of SP~2 carbon with a two-dimensional sheet structure.Its excellent electrical,thermal,optical and mechanical properties make it one of the most attractive materials.These make graphene as the main research object in the preparation of conductive fiber.In this study,the graphene composite conductive fiber was prepared by using ultrahigh molecular weight polyethylene(UHMWPE)fiber as the substrate and graphene and its hybrids as conductive coatings.The main contents are as follows:(1)Graphene oxide(GO)solution and its uniform and stable hybrid systems which were fabricated by mixing nano materials of different dimensions,such as carbon nanotubes(CNT),modified carbon nanotubes(tCNT),carbon black(CB)and montmorillonite(MMT),were prepared and used to the preparation of conductive fibers.(2)The inert surface of the UHMWPE fibers were modified by dopamine,and the influence of the temperature and the time of react on the fiber modification effect was investigated.The results showed that the fiber surface N/C ratio reached 0.074(highest)and its contact angle was 39.2 degrees(minimum)under the optimum condition of the dopamine concentration of 2 g/L,the reaction temperature in 50℃,the reaction time of6h.(3)The conductive composite fibers were prepared by impregnation reduction method,The effects of coating process and doping process on the conductivity of fiber are explored,and the effects of rGO composite coating on the properties of fiber thermal,mechanical is also studied.The optimum coating process include that the coating liquid concentration was 0.25wt%and the number of coating times was 4 times.In addition,the obtained composite fiber has the best electrical performance with the resistivity of 6.01×10~6Ω·cm when the mixture ratio between GO and tCNT was 3:1 in doping process.