▎ 摘　　要

NOVELTY - Preparation of high thermal conductivity graphene oxide and boron nitride composite film material includes adding natural graphite and potassium permanganate to 98% sulfuric acid, mixing for 1-2 hours in ice bath at 300-400 revolutions per minute to obtain mixture A, washing three times with 0.5 mol/L hydrochloric acid, washing 5-8 times with deionized water, drying at 80-100 degrees C for 12-24 hours, adding organic solvent, placing in ultrasonic at 100-500 Watt for 12-24 hours, centrifuging for 5-10 minutes, adding deionized water to lower layer precipitate, mixing for 10-30 minutes to obtain boron nitride nanosheet solution, mixing graphene oxide solution and boron nitride nanosheet solution for 1-21 hours, placing in ultrasonic at 500-1000 Watt for 90-180 minutes to obtain mixed solution of boron nitride and graphene, adding mixed solution of boron nitride and graphene to Buchner funnel with filter paper, filtering and drying at room temperature. USE - Method of preparing high thermal conductivity graphene oxide and boron nitride composite film material. ADVANTAGE - The material has 10-28 dielectric constant and 9.7-12.9 watt per meter Kelvin heat conducting coefficient. DETAILED DESCRIPTION - Preparation of high thermal conductivity graphene oxide and boron nitride composite film material comprises adding natural graphite and potassium permanganate to 98% sulfuric acid, mixing for 1-2 hours in ice bath at 300-400 revolutions per minute to obtain mixture A, heating mixture A to 35 degrees C for 1 hour, adding deionized water to mixture A, heating to 90-95 degrees C for 30-35 minutes to obtain mixture B, cooling mixture B to room temperature, adding 35% hydrogen peroxide solution to mixture B, reacting at 100-300 revolutions per minute (rpm) for 10 minutes at room temperature to obtain aqueous graphene oxide solution, centrifuging aqueous graphene oxide solution at 3000-3500 rpm to obtain supernatant liquid, centrifuging supernatant liquid at 8000-8500 rpm, freeze-drying at - 80 degrees C for 20-24 hours to obtain graphene oxide powder, dissolving graphene oxide powder in water to obtain graphene oxide solution, centrifuging graphene oxide solution at 4000-5000 revolutions per minute to obtain supernatant liquid, centrifuging supernatant liquid at 9000-10000 rpm to obtain lower layer precipitate, adding deionized water to lower layer precipitate, mixing at 100-500 rpm for 10-30 minutes to obtain graphene oxide solution, adding boron nitride powder and oxide to concentrated acid, mixing, reacting in ice water bath at 100-300 rpm for 60-120 minutes to obtain mixture A, heating mixture A at 50 degrees C, reacting, mixing at 50 degrees C at 100-300 rpm for 60-180 minutes, cooling to room temperature, adding deionized water to mixture B in ice water bath to obtain mixture C, centrifuging mixture C at 6000-8000 rpm for 5-15 minutes to obtain precursor of thin layer of boron nitride, washing three times with 0.5 mol/L hydrochloric acid, washing 5-8 times with deionized water, drying at 80-100 degrees C for 12-24 hours, adding organic solvent, placing in ultrasonic at 100-500 Watt for 12-24 hours, centrifuging at 3000 rpm for 5-10 minutes, taking upper layer to obtain ultrathin layer of boron nitride solution, filtering at 80-100 degrees C for 12-24 hours to obtain ultrathin layer of boron nitride powder, dissolving ultra-thin layer of boron nitride powder in deionized water to obtain 5-10 g/L ultra-thin layer of boron nitride aqueous solution, centrifuging at 4000-5000 rpm to obtain supernatant liquid, centrifuging supernatant liquid at 9000-10000 rpm to obtain lower layer precipitate, adding deionized water to lower layer precipitate, mixing at 100-500 rpm for 10-30 minutes to obtain boron nitride nanosheet solution, mixing graphene oxide solution and boron nitride nanosheet solution at 100-500 rpm for 1-21 hours, placing in ultrasonic at 500-1000 Watt for 90-180 minutes to obtain mixed solution of boron nitride and graphene, adding mixed solution of boron nitride and graphene to Buchner funnel with filter paper, filtering at room temperature under 0.1-0.5 MPa for 10-20 hours and drying at room temperature.