▎ 摘　　要

NOVELTY - A covalent bond connected low interface thermal resistance high heat-conducting modified graphene functional particles is prepared by modifying graphene oxide to obtain isocyanate-esterified graphene, mixing isocyanate-esterified graphene and surface hydroxylated heat-conducting filler, and connecting graphene with heat-conducting filler through urethane bond through chemical reaction between isocyanate and hydroxyl. USE - Covalent bond connected low interface thermal resistance high heat-conducting modified graphene functional particles. ADVANTAGE - The material improves heat-conducting performance and mechanical property. The method is simple, easy to implement and easy to be industrialized production, and relates to common equipment. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) a method for preparing covalent bond connected low interface thermal resistance high heat-conducting modified graphene functional particles comprising dispersing graphene oxide powder in solvent, orderly dripping hexamethylene diisocyanate and catalyst dibutyltin laurate, reacting under nitrogen atmosphere, filtering, washing, drying to obtain isocyanate-esterified graphene, weighing boron nitride and sucrose, uniformly mixing and pouring into ball milling tank of ball mill and installing ball milling device, ball milling, dispersing mixture in deionized water, filtering, washing, drying to obtain hydroxylated boron nitride filler, weighing isocyanate-esterified graphene and hydroxylated boron nitride, adding solvent, ultrasonically uniformly dispersing, dripping catalyst dibutyltin dilaurate, reacting under nitrogen atmosphere, filtering and washing and drying; (2) a natural rubber composite material prepared by covalent bond connected low interface thermal resistance high heat-conducting modified graphene functional particles comprising 100 pts. wt. natural rubber, 9 pts. wt. rubber auxiliary agent and 5-20 pts. wt. covalent bond connected low interface thermal resistance high heat-conducting modified graphene functional particles; and (3) a method for preparing natural rubber composite material comprising adding covalent bond connected low interface thermal resistance high heat-conducting modified graphene functional particles into deionized water, stirring to uniformly disperse, adding dispersion into natural latex, stirring to uniformly mix, adding formic acid for demulsification to obtain crude rubber, putting formic acid removed raw rubber into oven to dry, putting dried crude rubber in internal mixer for plasticating at 60degrees Celsius at 40 revolutions/minute, orderly adding zinc oxide and stearic acid, mixing for 2 minutes, discharging mixed rubber, adjusting temperature of mold cavity of internal mixer to 150degrees Celsius, putting mixed rubber into internal mixer, mixing for 5 minutes and discharging, cooling rubber material to room temperature, transferring to open mill for further mixing, adding vulcanization accelerator N-(oxydiethylene)-2-benzothiazole sulfenamide and sulfur in mixing process, uniformly mixing rubber material to obtain mixed rubber, standing for 20 hours, vulcanizing and molding on flat vulcanizing machine.