▎ 摘　　要

NOVELTY - Two-dimensional graphene/liquid metal (gallium-indium)/polydimethylsiloxane composite film comprises flexible polydimethylsiloxane substrate, graphene dispersion liquid and liquid metal (gallium-indium) poured onto it. USE - The two-dimensional graphene/liquid metal (gallium-indium)/polydimethylsiloxane composite film is useful as thermal conductive packaging material in 5G communication equipment and high-power electronic equipment (claimed); and flexible heat dissipation devices. ADVANTAGE - The two-dimensional graphene/liquid metal (gallium-indium)/polydimethylsiloxane composite film: exhibits folded bow-tie structure and has good conduction network, unique two-dimensional auxetic structure of graphene, low graphene and liquid metal content, excellent thermal and electrical conductivity and tensile rebound stability. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of two-dimensional graphene/liquid metal (gallium-indium)/polydimethylsiloxane composite film, comprising (1) mixing graphite, sodium nitrate and potassium permanganate, adding sulfuric acid, stirring for 5-8 hours, performing heat preservation at 35-60℃, adding deionized water, heating at 85-95℃ for 10-15 minutes, adding hydrogen peroxide and deionized water, cooling to room temperature, washing for three times, taking out product and freeze-drying to obtain graphene oxide, (2) dispersing 0.1 g graphene oxide obtained in step (1) in 10 ml deionized water to obtain 10 mg/ml graphene oxide aqueous solution, and adding 1 g graphene oxide microflakes, and dispersing by ultrasonic tip for 30 minutes to obtain graphene dispersion liquid having stable properties and uniform dispersion, (3) providing thickness requirements of different samples for thermal conductivity testing and mechanical testing, and three-dimensional printers to obtain 10 mm*10 mm*2 mm and 10 mm*10 mm*10 mm respectively of photosensitive resin skeletons having bow-tie structures of different sizes; component A is prepared in a 1:1 mass ratio or volume ratio of vinyl terminated polydimethylsiloxane and platinum catalyst and component B is a mixed solution of hydride-terminated poly(dimethylsiloxane) curing agent, pouring it into the bow-tie groove of photosensitive resin skeleton, curing at room temperature and demolding to obtain poly(dimethylsiloxane)matrix film with a two-dimensional folded-back bow-tie structure, (4) uniformly pouring the graphene dispersion into the polydimethylsiloxane matrix film, removing moisture in graphene dispersion by a vacuum oven and uniformly dispersing the graphene into the polydimethylsiloxane matrix film, (5) uniformly inject liquid gallium-indium into the polydimethylsiloxane matrix film of step (4) by a syringe and (6) providing a mixed solution of component A and component B, where component A is a vinyl-terminated polydimethylsiloxane and a platinum catalyst, and the B component is a hydride-terminated poly(dimethylsiloxane)siloxane) mixed solution of curing agent in mass ratio of 1:4-4:1, pouring the mixed solution onto the surface of the PDMS matrix film with graphene and liquid gallium-indium obtained in step (5), to encapsulate graphene and liquid gallium-indium to prevent leakage of graphene and liquid metal, curing at room temperature for 4-6 hours and freeze-drying to remove the residual moisture to obtain final product.