373 results about "Graphene membrane" patented technology

The invention discloses application of a metal ion doped graphene oxide film in catalytic synthesis of Schiff base. The metal ion doped graphene oxide film comprises a graphene oxide film and metal ions loaded on the surface and between layers of the graphene oxide film. Metal ions in the metal ion-doped graphene oxide film induce reactant molecule orientation through a cation-pi effect, and a confinement channel formed between the metal ions and GO is combined, so that a front line molecular orbit of a reactant for catalytic synthesis of the Schiff base is better matched, the molecular freedom degree is reduced, and the Schiff base catalytic synthesis efficiency is improved. And the molecules are subjected to bond breaking and bond forming reactions in a specific orientation. Molecules are orderly arranged among layers and flow to pass through a two-dimensional nano confinement channel provided by the graphene oxide nanosheets among the film layers, so that the reaction activation energy is reduced, and efficient catalytic synthesis of various Schiff bases is realized at room temperature. Meanwhile, by regulating and controlling the chemical microstructure of the membrane material, the catalytic reaction efficiency and the reaction selectivity can be effectively improved.

The invention provides a high-strength and high-heat-conductivity graphene heat-conducting gasket and a preparation method thereof, and provides a modified graphene film and a solution for arranging a curing layer to solve the technical problem that in the prior art, a graphene heat-conducting gasket is extremely prone to cracking and layering, and consequently the service life and the heat conductivity are affected. The graphene film specifically comprises a plurality of layers of modified graphene films, the adjacent modified graphene films are bonded through adhesive layers to form an integral structure, the integral structure is provided with a curing layer on the outer surface of the modified graphene films in the stacking direction, the modified graphene films are provided with a plurality of through holes in the stacking direction, and the through holes are arranged in an array mode. The strength of the graphene heat-conducting interface material is improved by modifying the graphene film; and the thermal conductivity in the Z-axis direction is greatly improved by carrying out oriented arrangement on the modified graphene film.

The invention relates to the technical field of heat dissipation materials, and discloses a graphite cooling fin of a multi-layer composite structure and a manufacturing process of the graphite cooling fin of the multi-layer composite structure. 15 to 25 parts of artificial graphite powder; 3 to 8 parts of an aniline-p-phenylenediamine copolymer; 2 to 6 parts of antimony oxide nano particles; 2 to 5 parts of urea; 1 to 3 parts of polyvinylpyrrolidone; the preparation method comprises the following steps: carrying out heat treatment on the artificial graphite film, and then carrying out mechanical pulverization; mixing the graphite oxide with an ethanol or water mixed solvent containing ammonia water; mixing the raw materials; performing vacuum defoamation and then coating on a base material; and performing carbonization treatment on the graphene film crude product, and performing lamination calendering treatment to form a final product. According to the technical scheme, the antimony oxide nano particles are adopted to synergistically adjust the heat conductivity, the effect of remarkably improving the transverse heat conductivity of the film body is achieved, the heat conductivity is enhanced, and material embrittlement caused by overfilling is avoided.

The invention provides an affinity carrier net for a cryoelectron microscope and a preparation method and application of a frozen sample of the affinity carrier net. The affinity carrier net comprises a carbonaceous bearing membrane covering the carrier net, a small organic molecule pyr-NHS connected with the carbonaceous bearing membrane, and a specific antibody protein connected with the small organic molecule pyr-NHS; the carbonaceous bearing film is a graphene film, a graphene oxide film or a carbon film. The method comprises the following steps: performing fusion expression on a PA tag having strong affinity interaction with an NZ-1 antibody on a target protein, and performing mixed incubation on an affinity carrier net fixed with an NZ-1 antibody protein and a cell lysis solution of the target protein which performs fusion expression on the PA tag; according to the method, efficient affinity purification and direct cryoelectron microscope sample preparation of the target protein with the PA tag in the cell lysis solution are realized, data collection and high-resolution structural analysis are carried out, the sample purification time and steps are reduced, the sample integrity is improved, the sample demand is reduced, and meanwhile, the problem of orientation tendency of sample distribution is solved.

The invention provides a heat dissipation composite material and a preparation method and application thereof. The heat dissipation composite material comprises a bonding layer, an insulating breathable layer, a heat conduction layer and a heat conduction diffusion layer which are sequentially arranged from bottom to top. Wherein the bonding layer is obtained by mixing and reacting a polymer matrix material, a composite filler and a molecular bridging agent, the insulating breathable layer is a porous insulating material, the heat conduction layer is a graphene film, and the heat conduction diffusion layer is prepared from porous matrix composite heat conduction nanoparticles. According to the invention, through combination and structural design of each layer of material, a synergistic effect of a multi-layer structure is realized, firm and stable bonding of the heat dissipation composite material and a heating electronic device is realized, the heat dissipation efficiency and insulation air permeability of the heat dissipation composite material are remarkably improved, and the heat dissipation requirement of high-power-density electronic equipment can be met.

Disclosed is a method of fabricating a self-standing Graphene Oxide (GO) membrane comprising a plurality of layers of crosslinked GO sheets, the method comprising using a crosslinking agent to crosslink between oxygen-containing functional groups of neighbour GO sheets, wherein the crosslinking agent is a metallic oxide or a carbide.

The invention relates to the field of aerospace thermal control, in particular to a star sensor light shield based on foam carbon and phase change materials, which comprises a foam carbon main body, and two phase change materials with different melting points are filled in pores of the foam carbon main body; the graphene film is co-cured on the outer surface of the foam carbon main body and completely covers the outer surface of the foam carbon main body; the heating sheets are adhered to the outer surface of the graphene film in the circumferential direction of the foam carbon main body to form different heating areas; the thermistors are adhered to the positions, corresponding to the heating areas, of the outer surface of the graphene film; the outer surface of the graphene film is covered with the multi-layer heat insulation assembly; and the temperature controller is used for adjusting the output power of the heating sheet by adopting a self-adaptive temperature control algorithm according to the temperature data acquired by the thermistor and the state of the phase change material, and controlling the temperature of the star sensor light shield within a preset temperature range. The direct solar radiation heat flow on the light shield can be effectively inhibited and dredged, and the high thermal stability control of the light shield is realized.

The invention discloses a multi-dimensional interface memristor, and belongs to the field of semiconductor devices, a metal oxide / graphene two-dimensional film material is used as a switch layer of the memristor, and the preparation method comprises the following steps: carrying out hydrophilization treatment on a graphene dispersion liquid, and then carrying out first ultrasonic dispersion; adding a metal oxide quantum dot dispersion liquid, and carrying out secondary ultrasonic dispersion, so that the metal oxide quantum dots are loaded on the surface of the graphene to obtain a successfully loaded solution; and plating the successfully loaded solution on the surface of a substrate by adopting a wet coating process, and drying to form a film, thereby obtaining the metal oxide / graphene two-dimensional film switch layer. Wherein the metal oxide is SnO2, TiO2, NiO2, CeO2 or IGZO (Indium Gallium Zinc Oxide). According to the invention, the oxide quantum dots are attached to the single-layer graphene film to form the zero-dimensional quantum dot / two-dimensional graphene composite film as the switch layer of the memristor, and the method can introduce a large number of oxide / graphene interfaces, so that the regulation and control effect of the interfaces on the photoelectric characteristics of the device can be amplified.

The present invention provides a high-thermal-conductivity and high-thickness graphene composite film and a preparation method therefor. The graphene composite film has a thickness of 1-2 mm, a thermal conductivity in the horizontal direction of 1500-1800 W / m•K and a thermal conductivity in the vertical direction of 100-200 W / m•K. The graphene composite film is obtained by mixing, coating, drying and sintering raw materials comprising a graphene oxide slurry, carbon fibers, carbon nanotubes and an adhesive dispersant, wherein on the basis of the mass of the graphene oxide slurry, the mass percentage of the carbon fibers is 4-7%, the mass percentage of the carbon nanotubes is 5-10%, and the mass percentage of the adhesive dispersant is 5-10%. The graphene composite film uses graphene oxide as a base material, and carbon fibers and carbon nanotubes of a certain length and diameter are added thereto to create a thermal conduction channel in the vertical direction. The synergistic combination of the three raw materials solves the current defect of it being difficult to balance the thickness and axial thermal conduction performance of a graphene film.

The invention relates to the technical field of brake discs, in particular to a carbon-ceramic brake disc with a composite functional layer and a preparation method of the carbon-ceramic brake disc. The problems that a brake disc is insufficient in strength and poor in ablation resistance are solved. The preparation method comprises the following steps: carrying out low-temperature plasma treatment and silicon dioxide sol impregnation on carbon fibers, and inserting a graphene oxide film between woven layers, so as to obtain a carbon fiber preform; primary densification is carried out through pretreatment activation, low-temperature permeation and high-temperature permeation, and two graphitization treatments are combined; siliconizing is carried out through low-pressure permeation, high-pressure strengthening and laser cladding, and secondary densification is carried out through precursor impregnation and cracking; the titanium zirconium silicide-nano aluminum oxide composite layer generated through the embedding process forms a compact oxidation film at high temperature, and the silicon carbide nano crystal whiskers are subjected to chemical vapor deposition, so that the strength and ablation resistance of the prepared carbon ceramic brake disc are improved.

The invention discloses a graphene film / copper hot-pressing composite directional high-thermal-conductivity material as well as a preparation method and application of the graphene film / copper hot-pressing composite directional high-thermal-conductivity material. The preparation method comprises the following steps: punching a graphene film to form a plurality of hole structures; blade-coating copper paste on the surface to form a liquid film; the copper paste comprises copper powder, a coupling agent and an organic phase; stacking a plurality of layers; carrying out hot pressing treatment on the circulating laminated structure; and slicing to obtain the graphene film / copper hot-pressing composite oriented high-thermal-conductivity material. When copper powder particles are embedded into the hole structure, the whole hole structure is filled with the copper powder particles, the copper powder particles can transversely enter gaps between graphene sheet layers, a three-dimensional interlocking structure is formed through the sintering effect, resin contained in the copper paste can be subjected to a carbonization reaction in the glue discharging stage, a carbon skeleton is formed, and therefore the three-dimensional interlocking structure is formed. And the infiltration process between the copper powder and the graphene sheet layer is facilitated, and finally the heat conduction performance and the mechanical performance of the graphene film / copper hot-pressing composite oriented high-heat-conduction material are remarkably improved.

The invention relates to a self-adhesion breathable laser-induced graphene film and a preparation method thereof. The self-adhesion breathable laser-induced graphene film is used for electromyographic signal detection. The method comprises the following steps: mixing a PDMS stock solution and a curing agent, coating a PET film with the mixture, covering a PI film, and curing to form the base plate. Then, PI powder and a PDMS solution are mixed, a curing agent and polyethylene glycol are added to adjust the adhesiveness, the mixture is dropped into a base plate after dilution, and vacuum defoaming and spin coating are conducted. The preparation method comprises the following steps: preparing a PEG film, inserting a micro-needle template, curing, pouring an Ecoflex solution, curing again, pulling out the micro-needle template to obtain a PI / PDMS / PEG film with breathability and self-adhesion, performing laser engraving by using a carbon dioxide laser to generate laser-induced graphene, and finally obtaining the self-adhesion breathable laser-induced graphene film. According to the membrane, human body surface electromyogram signals are collected by utilizing the characteristics of high conductivity and low signal-to-noise ratio of laser-induced graphene, the adhesion is adjusted through polyethylene glycol, the air permeability is realized through a microneedle template method, the application scene of a device is expanded, and an electrode patch capable of monitoring for a long time is provided for human body physiological signal detection.

The invention belongs to the technical field of graphene film preparation, and particularly relates to a graphene thick film preparation method, which comprises: mixing a boric acid aqueous solution and a graphene oxide dispersion liquid to obtain a boric acid / graphene oxide mixed dispersion liquid; after the mixed dispersion liquid of boric acid / graphene oxide is coated, a solvent is evaporated, and a boric acid doped graphene oxide film is prepared; and stacking a plurality of layers of boric acid doped graphene oxide films, performing pressurization treatment, and performing annealing treatment in an inert atmosphere to obtain the graphene thick film. The preparation method provided by the invention not only solves the problem of film interface effect of the graphene thick film in the prior art and remarkably improves the conductivity of the graphene thick film, but also realizes effective regulation and control of the thickness of the graphene thick film through a simple stacking mode, and the preparation method is suitable for large-scale production. Powerful support is provided for application of the graphene thick film in the fields of electrochemical energy storage, electromagnetic shielding, heat dissipation and electric conduction.

The invention relates to a heat dissipation surface expansion device based on a high-thermal-conductivity graphene film. The heat dissipation surface expansion device comprises a satellite body, single-machine equipment, a graphene film, a heat pipe and a bracket, the stand-alone device is installed inside the satellite body, and the graphene film and the support are installed outside the satellite body; the graphene film is connected with the satellite body and the support, and at least one heat pipe is connected to the graphene film. The device has the advantages that heat on a single machine is firstly transmitted to the satellite mounting plate and the graphite film, the heat dissipation surface is expanded through the graphene film, the heat conduction effect is enhanced through the heat pipe, and finally the heat is radiated to a cold space through the graphene film, so that the problem of insufficient heat dissipation capability of a satellite is solved; the whole set of device is high in structural reliability, the whole set of device product is not provided with movable parts, passive thermal control measures are adopted, and the problems of starting, stopping and failure of a system do not exist; the problem of heat dissipation of high-heat-consumption single-machine equipment under the conditions of satellite envelope and insufficient weight is solved.

The utility model discloses a continuous multilayer copper-graphene composite film and a preparation device thereof, and belongs to the field of copper-graphene composite film preparation. According to the device disclosed by the utility model, the copper-graphene composite film layer is prepared on the surface of the copper foil by arranging the copper-graphene composite film layer preparation unit, and a graphene film in the prepared copper-graphene composite film layer can keep integrity; in the whole preparation process, the composite film can be continuously prepared and obtained only by keeping continuous winding and unwinding of the copper carrying roller and the composite material winding roller, a subsequent pressing treatment procedure is not needed, the phenomenon of poor quality caused in the pressing process is avoided, the continuity and stability of the preparation process of the composite film are guaranteed, and the production efficiency is improved. The layered composite film with good combination can be obtained, and the technical problem that an existing device is low in preparation efficiency is solved.

The invention discloses a graphene piezoresistive accelerometer, which relates to the technical field of sensor measurement, and comprises a support frame, a central island, a plurality of metal electrodes, a plurality of groups of connecting beams, a plurality of graphene films and a plurality of mass blocks, each inner side wall of the supporting frame is connected with the outer wall of the center island through a set of connecting beams, each connecting beam comprises a sensitive beam and a plurality of supporting beams, and the mass blocks are installed on the back side of the center island, the back side of each sensitive beam and the back side of each supporting beam. All the metal electrodes and all the graphene films are installed on the front end face of the supporting frame, every two metal electrodes are connected with one graphene film, the first end of the sensitive beam is connected with the supporting frame, the graphene films are arranged corresponding to the first end of the sensitive beam, and the thickness of the first end of the sensitive beam is smaller than that of other positions of the sensitive beam. According to the invention, the sensitivity is good, the influence of the inherent frequency on the sensitivity is small, and a high G value can be realized.

Method of manufacturing a vertically aligned laminated graphene based thermally conductive film. The method comprising: attaching first and second graphene film using a layer of nanoparticles and an adhesive; forming a layered film comprising a predetermined number of graphene film layers by repeating the steps of arranging a layer of nanoparticles, arranging an adhesive and attaching a graphene film; and laminating the layered film by applying pressure and heat to cure the adhesive, thereby forming a laminate film; cutting the laminate film at an angle in relation to a surface plane of the film to form the vertically aligned laminated graphene based thermally conductive film.

The invention relates to a method for preparing an efficient electromagnetic shielding graphene film by using a rapid Joule heat technology, and belongs to the technical field of functional materials and application thereof. The method comprises the following steps: firstly, preparing a graphene oxide film through vacuum filtration, then carrying out pre-reduction treatment under the protection of argon, heating the film to 700 DEG C, and carrying out heat preservation for 1 hour so as to remove part of oxygen functional groups; and then, soaking the pre-reduced film in a ferric chloride ethanol solution, introducing a Fe3O4 nanoparticle precursor, and carrying out discharge treatment for 0.1 second under the voltage of 100V through a rapid Joule thermal reduction technology to realize rapid reduction of graphene oxide and doping of Fe3O4 nanoparticles. The finally prepared graphene film shows excellent electromagnetic shielding effectiveness in an X wave band (8-12 GHz), the electromagnetic shielding effectiveness reaches 38 dB, and the electromagnetic shielding effectiveness is improved by 2 dB compared with a sample (36 dB) not doped with Fe3O4. The method has the advantages of being easy and convenient to operate, low in energy consumption and high in reduction efficiency, meanwhile, the synergistic effect of conductivity loss, magnetic loss and dielectric loss is achieved through introduction of the Fe3O4 nanoparticles, the electromagnetic shielding performance of the material is remarkably improved, and the method is suitable for the fields of electromagnetic interference protection of electronic equipment and the like.

The invention discloses a preparation method of a high-resilience graphene foamed film, which is characterized in that on the basis of traditional hydrazine hydrate foaming, tert-butyl alcohol is introduced as a regulator, so that the problem of non-uniform pore size distribution in a graphene film caused by rapid reduction of hydrazine hydrate is avoided, and the compression resistance and resilience of the whole material are improved by virtue of a fine pore structure. And through subsequent low-temperature thermal reduction, carbonization and graphitization treatment, the conjugated structure of the graphene is further recovered, and the porous membrane skeleton is endowed with high compression resilience performance. The obtained high-resilience foaming film can be used as a base material of materials for phase change heat storage, batteries, capacitors, thermal interfaces and the like, and preparation of a high-mechanical-property composite material is achieved.

The invention belongs to the technical field of graphite metal composite heat dissipation devices, and provides a flexible graphene film heat conduction cable and a preparation method thereof.The preparation method comprises the steps that the surface of a graphene film is cleaned and punched, and the graphene film with micron-sized pores in the surface is obtained; sequentially plating a layer of active metal film and a layer of heat-conducting metal film on the surface of the graphene film, and cutting to obtain a graphene film; graphene films are overlaid layer by layer to obtain a laminated material, and the two ends of the laminated material are clamped to a hot-pressing mold to be subjected to hot-pressing welding treatment, so that a locally connected flexible heat conduction section is obtained; and the flexible heat conduction section and the heat conduction metal shell are assembled, a soldering lug is placed for brazing and finish machining, and the flexible graphene film heat conduction cable is obtained. According to the method, the internal connection problem of the flexible section is solved by establishing a synergistic process of surface punching, double-layer coating and hot pressing, the heterogeneous connection problem of the flexible section and the shell is solved in a manner of sampling coating and brazing, and through the synergistic effect of all links, the overall performance and reliability of the heat-conducting cable are remarkably improved.

The invention relates to the technical field of active cables, in particular to an active cable made of black phosphorus-graphene oxide. The active cable is provided with a plurality of electrical cores, each electrical core comprises a pair of parallel wire assemblies, an outer shielding layer is arranged on the outer side of each wire assembly, and a wire pair shielding layer and a sheath layer are sequentially arranged on the outer side of each outer shielding layer in a sleeving mode; the wire assembly comprises an inner conductor and an inner shielding layer which are coaxially arranged, and the inner shielding layer wraps the outer side of the inner conductor; the inner surface of the outer shielding layer and the outer surface of the inner shielding layer form a cavity, and the cavity is filled with an insulating layer. The inner shielding layer is a black phosphorus-graphene oxide film inner shielding layer. According to the active cable, the inner shielding layer made of black phosphorus-graphene oxide is arranged outside the inner conductor, so that the active cable has the advantages of long-distance transmission, high temperature resistance, good mechanical performance and the like.

The invention discloses a preparation method of a recycled graphene film composite heat-conducting substrate, which comprises the following steps: preparing graphite powder from recycled graphene film waste: recycling the graphene film waste, and crushing the recycled graphene film waste to obtain graphene powder with the size of 40-100 meshes; the recovered graphene film waste is crushed and sieved to obtain graphene powder with the size of 100 meshes; according to the graphene heat-conducting substrate, the recycled graphene waste and the expanded graphite are integrated, the graphene waste and the expanded graphite serve as heat-conducting filler and have excellent heat conductivity, the heat conductivity of the heat-conducting substrate can be improved through introduction of graphene, particles of the heat-conducting filler are in close contact with one another through wrapping of the graphene filler and the expanded graphite, and a heat-conducting channel is formed; the waste graphene leftover materials are recycled, waste is turned into wealth, resources are saved, a product with a high additional value is prepared, energy conservation and emission reduction can be achieved in the aspect of environmental protection, and cost can be reduced and benefit can be increased in the aspect of cost.

The invention relates to the technical field of high-thermal-conductivity and high-resilience graphene foam, in particular to a preparation method of elastic graphene foam, according to the scheme, by adding a hollow material, the porosity of an original material graphene oxide film is improved. Meanwhile, the graphene foam with multiple micropores and high porosity is obtained through clamp constraint and a high-temperature heat treatment process, so that organic macromolecules can permeate into the graphene foam to form a framework, and the graphene foam with high thermal conductivity and high resilience is obtained; and the overflow speed of thermal decomposition gas can be controlled by adopting a heat treatment process with a certain temperature rising speed at 60-300 DEG C, so that the membrane is controlled not to be broken in the expansion process. And performing high-temperature graphitization to obtain the graphene foam with smooth surface, high expansion rate and high heat-conducting property, so that the high-expansion graphene oxide film permeates into organic polymers through a vacuum permeation method to form a framework, thereby obtaining the high-heat-conducting and high-resilience graphene foam.

The invention discloses functionalized graphene for removing tritium from radioactive waste liquid and a preparation method and application of a graphene film, the functionalized graphene is a flaky substance formed by stacking lamellar structures, and the distance between the stacked lamellar structures is 7.5-8.7. The preparation method comprises the following steps: preparing graphene oxide powder; performing sulfonation on the graphene oxide powder to obtain sulfonated graphene aerogel; performing carboxylation on the graphene oxide powder to obtain carboxylated graphene; and mixing and stirring the sulfonated graphene aerogel and carboxylated graphene to obtain the functionalized graphene. The tritium in the tritium-containing liquid is separated by utilizing the membrane formed by the functionalized graphene, and the tritium removal technology has the advantages of mild reaction conditions, low energy consumption, easiness in large-scale production and the like.

The invention discloses an in-plane and out-plane bidirectional high-strength graphene heat-conducting film and a preparation method and application thereof.A small amount of epoxy resin is filled into a graphene film through a vacuum impregnation technology, interlayer stress transmission efficiency is improved by means of a tenon-and-mortise-like structure formed by the epoxy resin in air holes, and lamella slippage is inhibited; according to the present invention, the in-plane strength is increased to 2 times (63.3 MPa) of the conventional film, the out-plane strength is increased to 6 times (182.6 kPa), and the epoxy resin has characteristics of low ratio and non-continuous distribution so as to maintain the high level of 1325 W / mK of the heat conductivity coefficient. The method has the advantages of easily available raw materials and simple process, and provides a feasible path for industrialization of graphene materials.

The invention relates to a flexible high-thermal-conductivity graphite cold chain which comprises a graphene film laminated body and two metal terminals arranged at the two ends of the graphene film laminated body, and the part, fixed by the metal terminals, of the graphene film laminated body is a rigid section of the graphene film laminated body. The part, which is positioned between the two metal terminals and is not fixed, of the graphene film laminated body is a flexible section of the graphene film laminated body; and the flexible section of the graphene film laminated body is wrapped with a polyimide film. A glue filling groove is formed in the metal terminal; and heat-conducting glue is filled between the metal terminal and the rigid section of the graphene film laminated body. According to the invention, the high-thermal-conductivity graphene film and the metal terminal are compounded by filling the assembly gap with the heat-conducting glue, so that the contact thermal resistance of the edge of the laminated graphite film and the metal terminal is greatly reduced, and the heat transfer path in the thickness direction of the graphite cold chain is improved, thereby achieving the effect of improving the heat-conducting property of the graphite cold chain.

The invention belongs to the technical field of functional films, and particularly relates to a preparation method of a high-thickness graphene heat conduction film. Comprising the following steps: (1) low-functionalized graphene powder is taken as a raw material, the content of an additive in the raw material is not more than 20wt%, and the solvent content is not more than 10wt%; (2) carrying out hot press molding on the raw materials in the step (1) at the temperature of 25-300 DEG C to obtain a dense graphene thick film; and (3) carrying out heat treatment on the dense graphene thick film in the step (2) in an atmosphere furnace with the temperature of 1000-3300 DEG C for a certain time to ensure interlayer ordering and crystal graphitization, so as to obtain the graphene heat-conducting film with high thickness and high heat conductivity, the thickness of the graphene heat-conducting film can reach more than 200 microns, and the heat conductivity of the graphene heat-conducting film can reach more than 1300W / mK. The preparation method is simple in operation process, low in cost, easy in scale amplification and suitable for preparation and performance improvement of the ultra-high-thickness graphene heat-conducting film, and the application range of the graphene film in the fields of heat management, electromagnetic shielding, nuclear technology, high-end instrument equipment and the like is widened.

The invention belongs to a thermal interface material of electronic equipment, and particularly relates to a thermal interface material with high thermal conductivity and electric conductivity as well as a preparation method and application thereof. The thermal interface material with high thermal conductivity and electric conductivity comprises graphene films and oriented carbon fiber / silica gel composite layers which are alternately stacked, in the thermal interface material with high thermal conductivity and electric conductivity, the graphene films are neatly arranged in the vertical direction. The carbon fibers are also directionally arranged in the vertical direction and are almost parallel to the graphene film, and part of the carbon fibers are in direct contact with the graphene film; the raw materials of the carbon fiber / silica gel composite layer comprise a silica gel matrix, carbon fibers and ceramic micro powder. The graphene film has a core heat conduction function, and the oriented carbon fiber not only shares transmission work of part of heat, but also converges the heat to a graphene film trunk. The ceramic particles form a bridging structure in the interface area to reduce interface thermal resistance. Direction deflection and scattering loss in heat flow transfer are reduced to the maximum extent, and the problem of'heat conduction island 'of a traditional composite material is solved through the synergistic effect of multi-scale paths; the heat-conducting property and the mechanical property of the material are synergistically improved.

The invention discloses a preparation method of a graphene heat-conducting film. The preparation method comprises the following steps: preparing graphene oxide slurry with the solid content of 0.5-5%; completely immersing a jig in the graphene oxide slurry, wherein the jig is provided with at least one inclined surface for attaching the graphene oxide slurry; the jig is lifted up after being immersed for 1-120 seconds until the graphene oxide on the inclined surface does not flow any more, and then the jig is placed in a drying oven to be dried; repeating the immersing and drying treatment steps for at least one time, and forming a graphene oxide film on the inclined surface; sequentially carrying out low-temperature pretreatment, medium-temperature carbonization treatment and high-temperature graphitization treatment on the graphene oxide film to obtain a graphene low-density film; and calendering the graphene low-density film to obtain the graphene heat-conducting film. A customized jig is adopted, the jig is provided with at least one inclined face used for loading / coating graphene oxide slurry, the long-range orderliness of graphene oxide microchips in the self-assembly process is improved by means of the gravity effect, and therefore the heat conduction performance of the graphene heat conduction film is improved.

The invention discloses a preparation method of a high-elasticity low-thermal-impedance graphene thermal interface material, which comprises the following steps: vertically dripping graphene oxide slurry on a substrate to form a graphene oxide gel array with a pre-oriented structure, and finally depositing the graphene oxide slurry on the surface to obtain the high-elasticity low-thermal-impedance graphene thermal interface material. And drying to obtain a graphene oxide film with certain vertical orientation inside, and carrying out chemical reduction foaming and high-temperature graphitization to obtain the thermal interface material. In the foaming process, oxygen-containing functional groups on the surface of the graphene oxide are converted into gas, graphene sheets are expanded, physical crosslinking is formed at the edge lap joint positions of the graphene sheets due to the pi-pi conjugation effect, and a quadrilateral-like structure is formed. Compared with a horizontally formed graphene film, the material has the advantages that the proportion of the internal graphene sheets arranged along the vertical direction is higher, the horizontal heat conduction capability is improved, better compression resilience is provided, the thermal impedance is reduced, and the material has wide application potential in the field of thermal interface materials.