▎ 摘　　要

NOVELTY - A transparent insulating graphene composite heat conducting film comprises alternating structure layer which is formed by hydrogen bonding action between the cellulose film and the graphene film. The upper and lower surfaces are covered with composite film formed by mixing cellulose with boron nitride. USE - Transparent insulating graphene composite heat conducting film used in electronic device. ADVANTAGE - The transparent insulating graphene composite heat conducting film has high transparency, ultra-high anisotropy and high insulation effect. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of transparent insulating graphene composite heat conducting film, which involves filtering nanofiber dispersion, drying to obtain nanofiber film, washing with ethanol and deionized water, immersing nano cellulose film in aqueous solution of enriched graphene at concentration of 0.1-3 mg/ml for 5-10 minutes, washing and drying, immersing film in 0.1-3 mg/ml dispersion for 5-10 minutes, repeating process for 1-40 times to obtain nanocellulose-graphene composite film, putting nano-cellulose-graphene composite film into reducing solution with mass fraction of 50% at temperature of 90 degrees C for 2 hours to obtain nanocellulose-graphene composite thermal film, mixing nano cellulose and boron nitride in ratio of 1:1 into a mixed solution, ultrasonically dispersing for 30-40 minutes, and immersing nano cellulose-graphene composite thermal film in mixed solution for 5-10 minutes. The concentration of boron nitride solution is 1-2 mg/ml.