Production method of electrically conductive graphene composite fiber

Abstract

A graphene composite fiber includes graphene sheets and a polymer for aggregating the graphene sheets together. The polymer includes either or both of a hyperbranched polymer and polyvinyl alcohol. The graphene sheets and the polymer are stacked on each other to form a layered structure, and the graphene sheets are regularly arranged along an axial direction of the graphene composite fiber. In a production method of the graphene composite fiber, a graphene oxide is used as a raw material, which significantly improves tensile strength of the graphene composite fiber. Addition of the polymer provides good tenacity for the composite fiber. In a spinning process, rotated coagulant is used to increase a tensile force of a gelatinous fiber, so that the gelatinous fiber has high orientation and tacticity, thereby significantly improving strength of an obtained solid fiber. The final reduction process restores electrical conductivity of a graphene fairly well.

What is claimed is: 
     
         1 . A graphene composite fiber, comprising:
 graphene sheets; and   a polymer for aggregating the graphene sheets together, wherein the polymer comprises at least one of a hyperbranched polymer and polyvinyl alcohol, the graphene sheets and the polymer are interleaved and stacked to form a layered structure, and the graphene sheets are arranged along an axial direction of the graphene composite fiber.   
     
     
         2 . The graphene composite fiber according to  claim 1 , wherein the hyperbranched polymer comprises one or more of hyperbranched polyester, a hyperbranched polyamide, and hyperbranched polyglycidyl ether. 
     
     
         3 . The graphene composite fiber according to  claim 1 , wherein the polymer comprises one or two of hyperbranched polyester, a hyperbranched polyamide, hyperbranched polyglycidyl ether, and the polyvinyl alcohol. 
     
     
         4 . The graphene composite fiber according to  claim 1 , wherein the graphene composite fiber has a diameter of 5 to 5000 μm. 
     
     
         5 . A production method of an electrically conductive graphene composite fiber, the method comprising:
 adding 1 part by weight of a graphene oxide, 50 to 2000 parts by weight of a solvent, and 0.1 to 100 parts by weight of a polymer to a reactor, and stirring, so as to obtain a nanocomposite material spinning slurry of the polymer and graphene, wherein the polymer comprises at least one of a hyperbranched polymer and polyvinyl alcohol;   extruding the spinning slurry through a spinning nozzle with a diameter of 5 to 5000 pm at a rate of 1 to 100 mL/h, retaining the spinning slurry in rotated coagulant for 1 to 3600 s, to coagulate the spinning slurry into fibers; and   washing the coagulated fibers, drying the coagulated fibers in a vacuum, and then performing reduction to obtain the graphene composite fiber.   
     
     
         6 . The production method of an electrically conductive graphene composite fiber according to  claim 5 , wherein the polymer comprises one or two of hyperbranched polyester, a hyperbranched polyamide, hyperbranched polyglycidyl ether, and the polyvinyl alcohol. 
     
     
         7 . The production method of an electrically conductive graphene composite fiber according to  claim 6 , wherein the solvent of 50 to 2000 parts by weight comprises one or more of N-methyl-2-pyrolidone, N,N-dimethylformamide, and water. 
     
     
         8 . The production method of an electrically conductive graphene composite fiber according to  claim 6 , wherein the coagulant comprises one or more of a NaOH aqueous solution, a KOH aqueous solution, a CaCl2 aqueous solution, a NaOH methanol solution, a KOH methanol solution, a CaCl2 methanol solution, a NaOH ethanol solution, a KOH ethanol solution, a CaCl2 ethanol solution, diethyl ether, ethyl acetate, acetone, and petroleum ether. 
     
     
         9 . The production method of an electrically conductive graphene composite fiber according to  claim 6 , wherein the reduction method comprises thermal reduction or chemical reduction, wherein a reducing agent used in the chemical reduction comprises one or more of hydrazine hydrate, vitamin C, lysine, potassium hydroxide, sodium hydroxide, hydroiodic acid, and acetic acid. 
     
     
         10 . The production method of an electrically conductive graphene composite fiber according to  claim 5 , wherein the spinning nozzle comprises spinning capillaries.