▎ 摘　　要

NOVELTY - Preparation of graphene additive involves: (1) mixing graphite powder with a dispersing agent and a chelating agent in a mass ratio of 100:(3-5):(5-7), then processing the materials into micron-sized particles through an airflow crusher, dispersing the graphite powder in a solvent, adding a reducing agent, uniformly mixing to obtain a slurry and feeding the slurry into a section of grinding machine; (2) preparing a graphene slurry material; (3) preparing a metal oxide composite powder component; (4) preparing a surface-coated graphene-containing metal oxide composite powder; and (5) adding weighed titanate coupling agent and the surface-coated graphene-containing metal oxide composite powder in a mass ratio of 100:3-5 to a reactor, then adding toluene to immerse and dissolve, heating the reactor to carry out reflux reaction for 5-7 hours, distilling and recovering toluene, taking out the product in the reactor, drying, dispersing, and grinding to obtain the product. USE - The method is useful for preparing graphene additive, which is useful for heat conduction coating and in daily electronic products and electronic devices in aviation, aerospace or military fields. ADVANTAGE - The method prepares graphene additive with excellent heat dissipation properties, thermal conductivity and coating film strength and lightweight. DETAILED DESCRIPTION - The step (2) involves feeding the grinded slurry into a two-section grinding machine, where the two-section grinding machine is a constant-speed stirring and grinding machine, forming a stable liquid level in the constant-speed stirring process, so that the particles reaching the graphene level are floated on the liquid surface through the chelating agent, forming a flow guide groove, used for overflowing, in the upper end of an inner cylinder component of the stirring grinding machine, and continuously guiding out the graphene slurry through the flow guide groove to obtain a graphene slurry material. The step (3) involves mixing titanium dioxide, cobalt oxide, aluminum oxide and ferric oxide according to a mass ratio of 1:(2-4):(5-10):(8-12) into a ball milling tank, carrying out ball milling at a speed of 800-1000 rpm for 2-4 hours, putting the ball-milled slurry into a Buchner funnel for suction filtration, drying the obtained filter cake and grinding, putting the grinded mixture into a muffle furnace, carrying out heat treatment at 700-900 degrees C for 2-2.5 hours, then cooling to room temperature along with the furnace, putting the heat-treated mixture into a ball mill to carry out ball milling for 3.5-4.5 hours, carrying out suction filtration, drying and grinding to obtain a metal oxide composite powder component. The step (4) involves pouring the graphene slurry material obtained in step (2) into a reactor, then adding metal oxide composite powder, where the mass ratio of graphene slurry material and the metal oxide composite powder is 1:(5-7), then adding ethanol until the metal oxide composite powder is immersed, heating and refluxing for 4-6 hours, then taking out the reactants, carrying out suction filtration, drying and grinding to obtain a surface-coated graphene-containing metal oxide composite powder.