▎ 摘　　要

NOVELTY - Manufacture of graphene powder involves mixing 0.001-5 mol/L bromine-containing hyperbranched polyethylene copolymer, a fluorinated monomer, an anhydrous solvent (b) and a ligand in a reaction flask under nitrogen atmosphere, performing liquid nitrogen freezing-vacuum-thaw cycle operation, adding cuprous bromide under nitrogen atmosphere, stirring at 50-120 degrees C for 0.5-24 hours, separating, purifying to obtain a fluorine-containing hyperbranched polyethylene copolymer, mixing graphite powder, a solvent (c) and the fluorine-containing hyperbranched polyethylene copolymer in a container, sealing the container, ultrasonically stirring at constant temperature for 0.5-168 hours, centrifuging to remove large particles, collecting the upper layer dispersion to obtain a graphene dispersion containing a free polymer, vacuum filtering or centrifuging the graphene dispersion, washing the filter residue with a solvent (d), and drying at 25-100 degrees C for 0.5-48 hours. USE - Manufacture of graphene powder used in dispersion (all claimed). ADVANTAGE - The method enables simple and efficient manufacture of graphene powder with reduced generation of defects. DETAILED DESCRIPTION - Manufacture of graphene powder involves mixing 0.001-5 mol/L bromine-containing hyperbranched polyethylene copolymer, a fluorinated monomer, an anhydrous solvent (b) and a ligand in a reaction flask under nitrogen atmosphere, performing liquid nitrogen freezing-vacuum-thaw cycle operation, adding cuprous bromide under nitrogen atmosphere, stirring at 50-120 degrees C for 0.5-24 hours, separating, purifying to obtain a fluorine-containing hyperbranched polyethylene copolymer, mixing graphite powder, a solvent (c) and the fluorine-containing hyperbranched polyethylene copolymer in a container, sealing the container, ultrasonically stirring at constant temperature for 0.5-168 hours, centrifuging to remove large particles, collecting the upper layer dispersion to obtain a graphene dispersion containing a free polymer, vacuum filtering or centrifuging the graphene dispersion, washing the filter residue with a solvent (d), and drying at 25-100 degrees C for 0.5-48 hours. The anhydrous solvent (b) is chosen from tetrahydrofuran, toluene, anisole, chloroform, and petroleum ether. The ligand is chosen from pentamethyldiethylenetriamine and bipyridine. The fluorinated monomer is chosen from fluorine-containing acrylate monomer. The ratio of the fluorinated monomer, the ligand, the cuprous bromide and the bromine-containing hyperbranched polyethylene copolymer is 5-500:0.1-200:0.01-200:1. The graphite powder is chosen from natural phosphorus flaky graphite having average mesh number of 50-1000 mesh, expanded graphite, and intercalated graphite of various types of compounds. The solvent (c) is chosen from chloroform, tetrahydrofuran, dichloromethane, petroleum ether, acetone, dioxane, N,N-dimethylformamide, and N-methylpyrrolidone. The ratio of the fluorine-containing hyperbranched polyethylene copolymer and the graphite powder is 0.01-20:1. The addition amount of the solvent (c) is 0.5 ml/g to 10 L/g. An INDEPENDENT CLAIM is included for a graphene dispersion, which is obtained by adding 0.05-100 g/L graphene powder to a solvent (e) chosen from chloroform, tetrahydrofuran, dichloromethane, petroleum ether, acetone, dioxane, N,N-dimethylformamide, and N-methylpyrrolidone, and ultrasonically treating.