▎ 摘　　要

NOVELTY - Preparing high thermal conductivity thick film of large-scale graphene interface involves adding 10 g natural flake graphite in the reaction unit that 300-400 ml vitriol oil is housed, and keeping the reaction at (-10)-(0)degrees Celsius through the control of cold circulation system, stirring, and the stirring speed is 3-10 revoltions/minute, mixing uniformly, and adding 30 g of oxidizing agent, 1 g of oxidizing agent each time. The interval time between each time is 1 hours, until all the oxidizing agents are added, and kept the overall reaction temperature and local temperature at (-10)-0degrees Celsius, then added 3-5 L deionized water to dilute and 0.5 L hydrogen peroxide. The mixture is washed with 20 wt.% hydrochloric acid, and finally centrifuged and washed multiple times to obtain graphene oxide. The large-size graphene oxide is utilized to obtain the graphene oxide slurry. USE - Method for preparing high thermal conductivity thick film of large-scale graphene interface ADVANTAGE - The metho has material interface, which is more closely combined, and the vertical thermal conductivity of the graphene oxide interface material is higher, which further reduces the interface thermal resistance and improves the thermal conductivity of the thick film. DETAILED DESCRIPTION - Preparing high thermal conductivity thick film of large-scale graphene interface involves adding 10 g natural flake graphite in the reaction unit that 300-400 ml vitriol oil is housed, and keeping the reaction at (-10)-(0)degrees Celsius through the control of cold circulation system, stirring, and the stirring speed is 3-10 revoltions/minute, mixing uniformly, and adding 30 g of oxidizing agent, 1 g of oxidizing agent each time. The interval time between each time is 1 hours, until all the oxidizing agents are added, and kept the overall reaction temperature and local temperature at (-10)-0degrees Celsius, then added 3-5 L deionized water to dilute and 0.5 L hydrogen peroxide. The mixture is washed with 20 wt.% hydrochloric acid, and finally centrifuged and washed multiple times to obtain graphene oxide. The large-size graphene oxide is utilized to obtain the graphene oxide slurry whose concentration is controlled at 2-10 wt.%, to ensure that the graphene oxide has formed a three-dimensional network gel and does not flow. The graphene oxide gel is incubated in a water bath at 70-100degrees Celsius for 1 hours, and extruded the gel onto a film material with a thickness of 5-100 micrometer with a square die, and the die is at least 1 cm above the film material. The thickness is controlled at 50 nnometer to 50 micrometer, and the film-like material after laying is multi-layered, and obtained bulk thermally conductive composite material with alternately stacked film materials/graphite oxide films with a thickness of 50-10000 micrometer. The film-like material is subjected to gradient welding, and the applied gradient powers are respectively, then welded for 10 minutes under the condition of 60 watt output power, 15 minutes under the condition of 250 watt output power, and 15 minutes under the condition of 1000 watt output power, then welded for 15 minutes under the condition of 1600 watt output power, welded for 10 minutes under the condition of 2900 watt output power, and finally obtained the reduced large-size graphene homogeneous interface thermal conductive material.