High-strength and high-heat-conductivity graphene heat-conducting gasket and preparation method thereof

Abstract

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.

Description

Technical Field

[0001] The present application relates to the field of thermally conductive gaskets, and in particular to a high-strength and high-thermal-conductivity graphene thermally conductive gasket and a preparation method thereof. Background Art

[0002] With the rapid development of integration, high computing power and high power in AI technology, chips, servers and other fields, all sectors of society have put forward higher requirements for chips and other fields. Studies have shown that when the chip operating temperature is close to 70-80°C, the chip performance will decrease by about 10% for every 2°C increase in temperature; in addition, high temperature leads to a decrease in electron mobility, an increase in internal device noise, thermal expansion damage to the microstructure and reduced reliability; increased temperature often increases the leakage current and current gain of the chip, thereby increasing chip power consumption.

[0003] Thermal interface materials play an important role in the heat dissipation of electronic components and are widely used to fill the gaps between electronic components and heat sinks and make up for tolerances. As chip technology has gradually developed from 7nm to 2nm, the iteration of chips has entered a slowdown stage. Studies have shown that the current chip design computing power is much higher than the actual computing power, and heat accumulation is one of the most important factors. Therefore, enhancing the thermal conductivity of thermal interface materials is an effective method. Graphene is one of the materials with great potential in the field of thermal conduction and heat dissipation since the 21st century. Therefore, the development of high thermal conductivity graphene thermal pads is imminent.

[0004] Graphene is one of the strongest materials known in the world, and it also has toughness. Theoretically, the Young's modulus of graphene can reach 1TPa, and the tensile strength can reach 130GPa. Graphene has excellent thermal conductivity, and the theoretical thermal conductivity of a single layer of graphene is as high as 5300W / mK. Therefore, using the high thermal conductivity of graphene in thermal interface materials is an effective way to solve the increasingly serious problem of heat accumulation in electronic fields such as chips and servers.

[0005] However, in actual production, it is impossible to produce complete and centimeter-level single-layer graphene, so large π bonds between single graphene are often used to stack to form centimeter-level multi-layer graphene films that can be used in production and life. The graphene thermal conductive pads prepared by the prior art are very prone to cracking and delamination, which affects the service life and thermal conductivity. Summary of the invention

[0006] In view of the above problems, the present application is proposed to provide a high-strength and high-thermal-conductivity graphene thermally conductive pad and a preparation method thereof that overcomes the above problems or at least partially solves the above problems, including:

[0007] A high-strength and high-thermal-conductivity graphene thermal gasket comprises several layers of modified graphene films, wherein adjacent modified graphene films are bonded by an adhesive layer to form an integral structure, wherein a solidified layer is provided on the outer surface of the modified graphene films in the stacking direction of the integral structure, and the modified graphene films are provided with several through holes in the stacking direction, and the through holes are arranged in an array.

[0008] Preferably, the modified graphene film is obtained by modifying the graphene film using a potassium hydroxide solution and a coupling agent.

[0009] Preferably, the modified graphene film accounts for 40wt%-80wt%, and the adhesive layer accounts for 20wt%-60wt%.

[0010] Preferably, the coupling agent accounts for 0.01wt%-5wt%.

[0011] A method for preparing a high-strength and high-thermal-conductivity graphene thermally conductive gasket comprises the following steps:

[0012] Coating a potassium hydroxide solution on the surface of the graphene film, and then performing high-temperature activation on the graphene film after drying; or, performing high-temperature activation on the graphene film;

[0013] A plurality of through holes are prepared in the activated graphene membrane, and the through holes are immersed in a coupling agent solution;

[0014] Adhesive is used to stack and bond the impregnated graphene films, and then pressed and cured to obtain a prefabricated graphene thermal conductive pad;

[0015] Coating resin on the outer surface of the prefabricated graphene thermal conductive pad to form a solidified layer;

[0016] Cutting the prefabricated graphene thermally conductive gasket into sheets along the stacking direction of the graphene film, and polishing the cut surface;

[0017] The solidified layer in the sheet material which is perpendicular to the stacking direction of the graphene film is removed to obtain the target high-strength and high-thermal-conductivity graphene thermally conductive gasket.

[0018] Preferably, the concentration of the potassium hydroxide solution is 0.1%-10%, and the number of coatings is 1-10 times.

[0019] Preferably, the temperature of the high temperature activation is 200-600° C., and the time of the high temperature activation is 5-20 min.

[0020] Preferably, the concentration of the coupling agent is 0.01%-5%, the viscosity of the coupling agent is 5-50 mPa.s, and the immersion time is 10-60 min.

[0021] Preferably, the coupling agent includes one or more of a silane coupling agent, a titanate coupling agent, an aluminate coupling agent, a phosphate coupling agent, a borate coupling agent, a chromium complex, and a coupling agent of a higher fat, acid, alcohol, or ester.

[0022] Preferably, the polishing method includes one or more of chemical etching, water polishing, vibration polishing, ultrasonic polishing and dry polishing.

[0023] This application has the following advantages:

[0024] In the embodiments of the present application, in contrast to the technical problem in the prior art that "graphene thermally conductive gaskets are very prone to cracking and delamination, thus affecting service life and thermal conductivity", the present application provides a solution for modified graphene films and setting a solidified layer, specifically: comprising several layers of modified graphene films, adjacent modified graphene films are bonded by an adhesive layer to form an integral structure, the integral structure is provided with a solidified layer on the outer surface of the modified graphene film in the stacking direction, the modified graphene film is provided with several through holes in the stacking direction, and the through holes are arranged in an array. The strength of the graphene thermal conductive interface material is improved by modifying the graphene film; the thermal conductivity in the Z-axis direction is greatly improved by aligning the modified graphene film. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for use in the description of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 is a schematic diagram of a through hole of a graphene film provided in one embodiment of the present application;

[0027] Figure 2 It is a schematic diagram of step S4 of a method for preparing a high-strength and high-thermal-conductivity graphene thermally conductive gasket provided in one embodiment of the present application;

[0028] Figure 3 It is a schematic diagram of step S5 of a method for preparing a high-strength and high-thermal-conductivity graphene thermally conductive gasket provided in one embodiment of the present application;

[0029] Figure 4 This is a schematic structural diagram of a high-strength and high-thermal-conductivity graphene thermal pad provided in one embodiment of the present application;

[0030] Figure 5 It is a flow chart of the steps of a method for preparing a high-strength and high-thermal-conductivity graphene thermal gasket provided in one embodiment of the present application.

[0031] The reference numerals in the drawings of the specification are as follows:

[0032] 1. Graphene film; 2. Adhesive layer; 3. Reinforcement layer. DETAILED DESCRIPTION

[0033] In order to make the objects, features and advantages of the present application more obvious and understandable, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0034] The inventors analyzed the prior art and found that since the graphene layers are connected only by van der Waals forces, the layers are easily delaminated, resulting in the prepared graphene thermal conductive gasket being very prone to cracking and delamination, thereby affecting the service life and thermal conductivity.

[0035] Reference Figure 4 , showing a high-strength and high-thermal-conductivity graphene thermal gasket provided by an embodiment of the present application, comprising a plurality of layers of modified graphene films 1, adjacent modified graphene films 1 are bonded by adhesive layers 2 to form an integral structure, the integral structure is provided with a solidified layer on the outer surface of the modified graphene film 1 in the stacking direction, the modified graphene film 1 is provided with a plurality of through holes in the stacking direction, and the through holes are arranged in an array.

[0036] In the embodiments of the present application, in contrast to the technical problem in the prior art that "graphene thermally conductive gaskets are very prone to cracking and delamination, thus affecting service life and thermal conductivity", the present application provides a solution for modified graphene film and setting a solidified layer, specifically: comprising several layers of modified graphene film 1, adjacent modified graphene films 1 are bonded by adhesive layer 2 to form an integral structure, the integral structure is provided with a solidified layer on the outer surface of the modified graphene film 1 in the stacking direction, the modified graphene film 1 is provided with several through holes in the stacking direction, and the through holes are arranged in an array. The strength of the graphene thermal conductive interface material is improved by modifying the graphene film; the thermal conductivity in the Z-axis direction is greatly improved by aligning the modified graphene film.

[0037] Next, a high-strength and high-thermal-conductivity graphene thermally conductive gasket in this exemplary embodiment will be further described.

[0038] It should be noted that the stacking direction is the direction in which the modified graphene film is stacked by bonding through the adhesive layer 2. Figure 3 , the stacking direction is the cutting direction.

[0039] In one embodiment of the present application, the modified graphene film is modified by potassium hydroxide solution and / or high temperature activation and / or coupling agent.

[0040] It should be noted that the graphene film is immersed in a potassium hydroxide solution, and then high-temperature activated after drying, or the graphene film is directly subjected to high-temperature activation treatment, and then through-holes are prepared, and the through-hole graphene film is immersed in a coupling agent solution. Since graphene is an inert material, the coupling agent is introduced after the graphene surface is treated, and the chemical bond of the coupling agent links the adhesive and the graphene, thereby improving the strength of the graphene thermal interface material.

[0041] In one embodiment of the present application, the modified graphene film accounts for 40wt%-80wt%, and the adhesive layer accounts for 20wt%-60wt%.

[0042] As an example, the modified graphene film in the graphene thermal conductive pad accounts for 40wt%-80wt%, such as 40wt%, 45wt%, 50wt%, 55wt%, 60wt%, 65wt%, 70wt%, 75wt%, 80wt%.

[0043] As an example, the adhesive layer in the graphene thermally conductive gasket accounts for 20wt%-60wt%, such as 20wt%, 25wt%, 30wt%, 35wt%, 40wt%, 45wt%, 50wt%, 55wt%, 60wt%.

[0044] In one embodiment of the present application, the coupling agent accounts for 0.01wt%-5wt%.

[0045] As an example, the coupling agent in the graphene thermal conductive pad accounts for 0.01wt%-5wt%. For example, 0.01wt%, 0.05wt%, 0.1wt%, 0.15wt%, 0.2wt%, 0.25wt%, 0.3wt%, 0.35wt%, 0.4wt%, 0.45wt%, 0.5wt%, 0.55wt%, 0.6wt%, 0.65wt%, 0.7wt%, 0.75wt%, 0.8wt%, 0.85wt%, 0.9wt%, 0.95wt%, 1wt%, 1.5wt%, 2wt%, 2.5wt%, 3wt%, 3.5wt%, 4wt%, 4.5wt%, 5wt%.

[0046] Reference Figure 5 , showing a method for preparing a high-strength and high-thermal-conductivity graphene thermally conductive gasket provided in one embodiment of the present application;

[0047] The method comprises:

[0048] S1, coating a potassium hydroxide solution on the surface of the graphene film, and performing high-temperature activation on the graphene film after drying; or, performing high-temperature activation on the graphene film;

[0049] S2, preparing a plurality of through holes in the activated graphene film, and immersing the through holes in a coupling agent solution;

[0050] S3, using an adhesive to stack and bond the impregnated graphene films, pressing them to a preset height and then curing them to obtain a prefabricated graphene thermal pad;

[0051] S4, coating resin on the outer surface of the prefabricated graphene thermally conductive gasket to form a solidified layer;

[0052] S5, cutting the prefabricated graphene thermally conductive gasket into sheets along the stacking direction of the graphene film, and polishing the cut surface;

[0053] S6. Removing the solidified layer in the sheet material that is perpendicular to the stacking direction of the graphene film to obtain the target high-strength and high-thermal-conductivity graphene thermally conductive gasket.

[0054] Next, a method for preparing a high-strength and high-thermal-conductivity graphene thermally conductive gasket in this exemplary embodiment will be further described.

[0055] As described in step S1, a potassium hydroxide solution is coated on the surface of the graphene film, and the graphene film is activated at high temperature after drying; or, the graphene film is activated at high temperature.

[0056] It should be noted that the graphene film is directly subjected to high-temperature activation treatment, or the graphene film is surface treated by coating with potassium hydroxide solution, and a small amount of functional groups are introduced into the graphene film by high-temperature activation of the graphene film, thereby enhancing the bonding strength between the graphene film and the adhesive, and at the same time, the thermal conductivity of the graphene film is not significantly reduced. Potassium hydroxide solution can increase the surface activity of the graphene film, making the graphene film easier to combine with the coupling agent and the adhesive, thereby improving the strength and thermal conductivity of the graphene thermal conductive gasket. The potassium hydroxide solution is applied by one or more of brushing, roller coating and spraying.

[0057] As an example, the concentration of potassium hydroxide solution is 0.1%-10%, for example 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3 / 5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, wherein 1%-5% is preferred.

[0058] As an example, the number of coatings is 1-10 times, such as 1 time, 2 times, 3 times, 4 times, 5 times, 6 times, 7 times, 8 times, 9 times, 10 times, wherein 4-7 times is preferred.

[0059] As an example, the graphene film is formed by self-assembly of multiple single-layer graphene, and the thickness of the graphene film is 50-1000 microns, for example, 20 microns, 100 microns, 150 microns, 200 microns, 250 microns, 300 microns, 350 microns, 400 microns, 450 microns, 500 microns, 550 microns, 600 microns, 650 microns, 700 microns, 750 microns, 800 microns, 850 microns, 900 microns, 950 microns, and 1000 microns, and the thickness of the graphene film is preferably 300-500 microns.

[0060] As an example, the high-temperature activation temperature is 200-600°C, for example 200°C, 250°C, 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, 600°C, wherein the activation temperature is preferably 400-500°C; the high-temperature activation time is 5-20min, for example 5min, 6min, 7min, 8min, 9min, 10min, 11min, 12min, 13min, 14min, 15min, 16min, 17min, 18min, 19min, 20min, wherein the activation time is preferably 7-10min.

[0061] As described in step S2, a plurality of through holes are prepared in the activated graphene membrane, and the through holes are immersed in a coupling agent solution.

[0062] It should be noted that by preparing through holes on the graphene film, the surface area of ​​the graphene film is increased, making it easier to combine with the coupling agent and the adhesive. By adding a coupling agent, the surface of the graphene film is modified, the chemical bonding points between the graphene film and the adhesive are increased, and the bonding strength between the graphene film and the adhesive is greatly improved.

[0063] Reference Figure 1 A plurality of through holes penetrating the upper and lower surfaces are formed on the activated graphene film, and an array of through holes is arranged on the graphene film.

[0064] As an example, the through holes are formed by one or more of mechanical die stamping, laser drilling and needle punching. The shape of the through holes is one or more of circular, square, diamond, triangular and elliptical. The arrangement shape of the through holes is one or more of square, diamond, triangular and polygonal.

[0065] As an example, the diameter of the through hole is 0.01-2mm, for example 0.01mm, 0.05mm, 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.75mm, 0.8mm, 0.85mm, 0.9mm, 0.95mm, 1mm, 1.5mm, 2mm, wherein the hole is preferably 0.05-1mm.

[0066] As an example, the hole spacing of the through holes is 0.01-2mm, for example, 0.01mm, 0.05mm, 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.75mm, 0.8mm, 0.85mm, 0.9mm, 0.95mm, 1mm, 1.5mm, 2mm, and the hole spacing is preferably 0.05-1mm.

[0067] As described in step S3, the impregnated graphene films are stacked and bonded with an adhesive, pressed and then cured to obtain a prefabricated graphene thermal pad.

[0068] It should be noted that an adhesive is applied to the surface of the first graphene film, and the second graphene film is stacked on the first graphene film, and the stacking is repeated in sequence until the target number of layers is stacked, and then pressed and cured. The multiple layers of graphene film are bonded together by the adhesive to form an overall structure with a certain thickness and strength, thereby improving the strength and thermal conductivity of the material.

[0069] As an example, the adhesive includes one or more of phenolic resin, urea-formaldehyde resin, epoxy resin, unsaturated polyester, polyurethane, polyvinyl acetate, polyvinyl alcohol, polyvinyl acetal, acrylate, polyvinyl chloride, nylon, chloroprene rubber, styrene-butadiene rubber, butyl rubber, nitrile rubber, silicone rubber, phenolic-nitrile, epoxy-nitrile, epoxy-polyurethane and epoxy-phenolic. The adhesive is preferably silicone rubber; the silicone rubber is preferably liquid silicone rubber; the liquid type is one-component liquid silicone, two-component condensation liquid silicone, and two-component addition liquid silicone; the liquid includes one or more of poly(dimethylsiloxane-co-methylphenylsiloxane), poly(dimethylsiloxane-co-alkylmethylsiloxane), polyphenylmethylsiloxane, poly(methylhydrogensiloxane), polymethylhydrogensiloxane, poly[dimethylsiloxane-co-(3-aminopropyl)methylsiloxane], poly[dimethylsiloxane-co-(2-(3,4-epoxycyclohexyl)ethyl)methylsiloxane], poly(dimethylsiloxane), polymethylsiloxane, α-(3-aminopropyl)dimethylsilyl-ω-[(3-aminopropyl)dimethylsilyloxy], poly[oxy(methyloctylsilene)], polydimethylsiloxane and cyclic polydimethylsiloxane.

[0070] As an example, the curing temperature is 100-300°C, such as 100°C, 120°C, 140°C, 160°C, 180°C, 200°C, 220°C, 240°C, 260°C, 280°C, 300°C, and the curing temperature is preferably 150-250°C.

[0071] As an example, the curing time is 1-10 hours, for example, 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, and the curing time is preferably 4-7h.

[0072] As described in step S4, resin is coated on the outer surface of the prefabricated graphene thermal conductive gasket to form a solidified layer.

[0073] It should be noted that, refer to Figure 2 After curing and forming, the prefabricated graphene thermal conductive gasket is reinforced with resin around the periphery and the upper and lower surfaces. By reinforcing and curing the graphene thermal interface material around the periphery, the strength of the graphene thermal interface material during the grinding process is improved to eliminate the situation where it is easy to be damaged during the subsequent grinding process.

[0074] As an example, the resin includes one or more of phenolic resin, epoxy resin, unsaturated polyester resin, melamine-formaldehyde resin, furan resin, polybutadiene resin, silicone resin, polyurethane, polyethylene, polyvinyl chloride, polyimide, polycarbonate, polyoxymethylene, polyphenylene ether, ABS resin, polyphenylene sulfide, polyether sulfone and polymethyl methacrylate.

[0075] As an example, the resin thickness is 1 mm-10 mm, for example, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, and the resin thickness is preferably 4-7 mm.

[0076] As described in step S5, the prefabricated graphene thermal conductive gasket is cut into sheets along the stacking direction of the graphene film, and the cut surface is polished.

[0077] It should be noted that along the stacking direction, that is Figure 3 The prefabricated graphene thermal conductive pad is cut into sheets in the height direction, and the cut surface is polished with sandpaper or other means, and then cleaned and dried. By polishing, the surface roughness of the graphene thermal interface material is reduced, the thickness uniformity is improved, and the thickness of the graphene thermal interface material is further reduced, which is suitable for application fields with lower thickness requirements.

[0078] As an example, the cutting method is one of blade cutting, plasma cutting, laser cutting, ultrasonic cutting, hot wire cutting, water jet cutting, wire cutting, electric spark cutting, electron beam cutting and vibration cutting.

[0079] As described in step S6, the solidified layer in the sheet material that is perpendicular to the stacking direction of the graphene film is removed to obtain the target high-strength and high-thermal-conductivity graphene thermally conductive gasket.

[0080] It should be noted that, refer to Figure 4 , remove the reinforcing resin around the dried sheet to obtain the target graphene thermal conductive pad. The density of the graphene thermal conductive pad prepared by the above preparation method is 0.2-0.5g / cm 3 , thermal conductivity reaches 110-180W / mK; tensile strength reaches 200-300KPa; and the rebound rate reaches 80%-90% of the original thickness.

[0081] As an example, the thickness of the graphene thermal pad is 0.05-5 mm, for example, 0.05 mm, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 0.95 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm or 5 mm.

[0082] In the following embodiments, silane coupling agent is used as coupling agent and liquid silicone is used as adhesive to prepare graphene thermal conductive interface material, and the thickness of graphene thermal conductive interface material is 100 microns.

[0083] The effective thermal resistance and compressibility of graphene thermal conductive interface materials were tested under 10psi, 20psi, 30psi, and 40psi conditions according to ASTM D5470 standard.

[0084] The thickness of the thermal interface material after 20psi and 40psi compression recovery is tested according to ASTM D374 standard.

[0085] The compression rebound performance of graphene thermal conductive interface material under 50% strain condition was tested according to ASTM D575 standard.

[0086] The tensile strength of graphene thermal interface materials was tested according to ASTM 882.

[0087] Example 1

[0088] This embodiment describes a high-strength and high-thermal-conductivity graphene thermal interface material, and its preparation process parameters are as follows:

[0089] In this embodiment, the graphene film accounts for 40wt% and the adhesive accounts for about 60wt%;

[0090] The concentration of KOH solution applied was 5%, the number of applications was 5, the activation temperature was 400°C, and the activation time was 7 minutes;

[0091] The diameter of the holes on the upper and lower surfaces of the graphene membrane is 0.05 mm, and the hole spacing is 0.05 mm;

[0092] The coupling agent concentration was 2%, and the immersion time was 35 min;

[0093] The curing temperature of the adhesive is 150°C and the curing time is 7h;

[0094] The surrounding reinforcement resin is phenolic resin, and the thickness of the resin is 5mm;

[0095] The grinding method adopted is water grinding;

[0096] The performance test results of the samples are shown in Table 1.

[0097] Example 2

[0098] This embodiment describes a high-strength and high-thermal-conductivity graphene thermal interface material, and its preparation process parameters are as follows:

[0099] In this embodiment, the graphene film accounts for 45wt% and the adhesive accounts for about 55%;

[0100] The thickness of the graphene film is 200 microns;

[0101] The concentration of KOH solution applied was 5%, the number of applications was 5, the activation temperature was 400°C, and the activation time was 7 minutes;

[0102] The diameter of the holes on the upper and lower surfaces of the graphene membrane is 0.05 mm, and the hole spacing is 0.05 mm;

[0103] Coupling agent selection: coupling agent concentration is 2% and immersion time is 35min;

[0104] The curing temperature of the adhesive is 180°C and the curing time is 7h;

[0105] The surrounding reinforcement resin is epoxy resin, and the thickness of the resin is 5mm;

[0106] The grinding method adopted is water grinding;

[0107] The performance test results of the samples are shown in Table 1.

[0108] Example 3

[0109] This embodiment describes a high-strength and high-thermal-conductivity graphene thermal interface material, and its preparation process parameters are as follows:

[0110] In this embodiment, the graphene film accounts for 50wt% and the adhesive accounts for about 50wt%;

[0111] The thickness of the graphene film is 300 microns;

[0112] The concentration of KOH solution applied was 0.5%, the number of applications was 5, the activation temperature was 400°C, and the activation time was 8 min;

[0113] The diameter of the holes on the upper and lower surfaces of the graphene membrane is 0.1 mm, and the hole spacing is 0.1 mm;

[0114] The coupling agent concentration was 0.5%, and the immersion time was 30 min;

[0115] The curing temperature of the adhesive is 150°C and the curing time is 8h;

[0116] The surrounding reinforcement resin is polyphenylene ether resin, and the resin thickness is 5mm;

[0117] The grinding method adopted is ultrasonic grinding;

[0118] The performance test results of the samples are shown in Table 1.

[0119] Example 4

[0120] This embodiment describes a high-strength and high-thermal-conductivity graphene thermal interface material, and its preparation process parameters are as follows:

[0121] In this embodiment, the graphene film accounts for 55wt% and the adhesive accounts for about 45wt%;

[0122] The thickness of the graphene film is 300 microns;

[0123] The concentration of KOH solution was 1%, the number of coatings was 4 times, the activation temperature was 400°C, and the activation time was 8 minutes;

[0124] The diameter of the holes through the upper and lower surfaces of the graphene membrane is 0.2 mm, and the hole spacing is 0.1 mm;

[0125] Coupling agent selection: coupling agent concentration is 1% and immersion time is 30min;

[0126] The curing temperature of the adhesive is 150°C and the curing time is 8h;

[0127] The surrounding reinforcement resin is ABS resin, and the resin thickness is 4mm;

[0128] The grinding method adopted is vibration grinding;

[0129] The performance test results of the samples are shown in Table 1.

[0130] Example 5

[0131] This embodiment describes a high-strength and high-thermal-conductivity graphene thermal interface material, and its preparation process parameters are as follows:

[0132] In this embodiment, the graphene film accounts for 60wt% and the adhesive accounts for about 40wt%;

[0133] The thickness of the graphene film is 300 microns;

[0134] The concentration of KOH solution applied was 3%, the number of applications was 5, the activation temperature was 500°C, and the activation time was 10 min;

[0135] The diameter of the holes through the upper and lower surfaces of the graphene membrane is 0.3 mm, and the hole spacing is 0.5 mm;

[0136] The coupling agent concentration was 2%, and the immersion time was 35 min;

[0137] The curing temperature of the adhesive is 200°C and the curing time is 8h;

[0138] The surrounding reinforcement resin is polycarbonate, and the thickness of the resin is 6mm;

[0139] The grinding method adopted is dry grinding;

[0140] The performance test results of the samples are shown in Table 1.

[0141] Example 6

[0142] This embodiment describes a high-strength and high-thermal-conductivity graphene thermal interface material, and its preparation process parameters are as follows:

[0143] In this embodiment, the graphene film accounts for 65wt% and the adhesive accounts for about 35wt%;

[0144] The thickness of the graphene film is 300 microns;

[0145] The concentration of KOH solution applied was 0.8%, the number of applications was 4, the activation temperature was 400°C, and the activation time was 7 minutes;

[0146] The diameter of the holes penetrating the upper and lower surfaces of the graphene membrane is 0.1 mm, and the hole spacing is 0.2 mm;

[0147] The coupling agent concentration was 1%, and the immersion time was 30 min;

[0148] The curing temperature of the adhesive is 150°C and the curing time is 6h;

[0149] The surrounding reinforcement resin is polyoxymethylene, and the thickness of the resin is 4mm;

[0150] The grinding method adopted is water grinding;

[0151] The performance test results of the samples are shown in Table 1.

[0152] Example 7

[0153] This embodiment describes a high-strength and high-thermal-conductivity graphene thermal interface material, and its preparation process parameters are as follows:

[0154] In this embodiment, the graphene film accounts for 70wt% and the adhesive accounts for about 30wt%;

[0155] The thickness of the graphene film is 200 microns;

[0156] The concentration of KOH solution applied was 3%, the number of applications was 4, the activation temperature was 400°C, and the activation time was 7 minutes;

[0157] The diameter of the holes through the upper and lower surfaces of the graphene membrane is 0.5 mm, and the hole spacing is 1 mm;

[0158] The coupling agent concentration was 2%, and the immersion time was 30 min;

[0159] The curing temperature of the adhesive is 150°C and the curing time is 6h;

[0160] The surrounding reinforcement resin is polyphenylene sulfide, and the resin thickness is 5mm;

[0161] The grinding method used is water grinding

[0162] The performance test results of the samples are shown in Table 1.

[0163] Example 8

[0164] This embodiment describes a high-strength and high-thermal-conductivity graphene thermal interface material, and its preparation process parameters are as follows:

[0165] In this embodiment, the graphene film accounts for 70wt% and the adhesive accounts for about 30wt%;

[0166] The thickness of the graphene film is 300 microns;

[0167] High temperature activation, temperature is 500℃, activation time is 8min;

[0168] The diameter of the holes on the upper and lower surfaces of the graphene membrane is 0.1 mm, and the hole spacing is 0.1 mm;

[0169] The coupling agent concentration was 1%, and the immersion time was 30 min;

[0170] The curing temperature of the adhesive is 120°C and the curing time is 8h;

[0171] The surrounding reinforcement resin is polyetheretherketone, and the resin thickness is 5mm;

[0172] The grinding method adopted is ultrasonic grinding;

[0173] The performance test results of the samples are shown in Table 1.

[0174] Example 9

[0175] This embodiment describes a high-strength and high-thermal-conductivity graphene thermal interface material, and its preparation process parameters are as follows:

[0176] In this embodiment, the graphene film accounts for 75wt% and the adhesive accounts for 25wt%;

[0177] The thickness of the graphene film is 200 microns;

[0178] High temperature activation, temperature is 400℃, activation time is 7min;

[0179] The diameter of the holes on the upper and lower surfaces of the graphene membrane is 0.5 mm, and the hole spacing is 0.5 mm;

[0180] The coupling agent concentration was 2%, and the immersion time was 35 min;

[0181] The curing temperature of the adhesive is 150°C and the curing time is 9h;

[0182] The surrounding reinforcement resin is polyethersulfone, and the resin thickness is 6mm;

[0183] The grinding method adopted is water grinding;

[0184] The performance test results of the samples are shown in Table 1.

[0185] Example 10

[0186] This embodiment describes a high-strength and high-thermal-conductivity graphene thermal interface material, and its preparation process parameters are as follows:

[0187] In this embodiment, the graphene film accounts for 70wt% and the adhesive accounts for about 30wt%;

[0188] The thickness of the graphene film is 200 microns;

[0189] The concentration of KOH solution applied was 1%, the number of applications was 5, the activation temperature was 400°C, and the activation time was 7 minutes;

[0190] The diameter of the holes on the upper and lower surfaces of the graphene membrane is 0.5 mm, and the hole spacing is 0.5 mm;

[0191] The coupling agent concentration was 3%, and the immersion time was 30 min;

[0192] The curing temperature of the adhesive is 150°C and the curing time is 6h;

[0193] The surrounding reinforcement resin is polymethyl methacrylate, and the thickness of the resin is 4mm;

[0194] The grinding method adopted is ultrasonic grinding;

[0195] The performance test results of the samples are shown in Table 1.

[0196] Table 1 Sample performance test results

[0197]

[0198]

[0199] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present application.

[0200] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0201] The above is a detailed introduction to a high-strength and high-thermal-conductivity graphene thermal conductive gasket and a preparation method thereof provided by the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea; at the same time, for general technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A high-strength and high-thermal-conductivity graphene thermally conductive gasket, characterized in that: It comprises several layers of modified graphene films, wherein adjacent modified graphene films are bonded by adhesive layers to form an integral structure, wherein the outer surface of the modified graphene films in the stacking direction of the integral structure is provided with a solidified layer, and the modified graphene films are provided with several through holes in the stacking direction, and the through holes are arranged in an array.

2. The high-strength and high-thermal-conductivity graphene thermally conductive gasket according to claim 1, characterized in that: The modified graphene film is prepared by modifying the graphene film using potassium hydroxide solution and / or high temperature activation and / or a coupling agent.

3. The high-strength and high-thermal-conductivity graphene thermally conductive gasket according to claim 1, characterized in that: The modified graphene film accounts for 40wt%-80wt%, and the adhesive layer accounts for 20wt%-60wt%.

4. The high-strength and high-thermal-conductivity graphene thermally conductive gasket according to claim 2, characterized in that: The coupling agent accounts for 0.01wt%-5wt%.

5. A method for preparing a high-strength and high-thermal-conductivity graphene thermally conductive gasket, characterized in that: Includes steps: Coating a potassium hydroxide solution on the surface of the graphene film, and then performing high-temperature activation on the graphene film after drying; or, performing high-temperature activation on the graphene film; A plurality of through holes are prepared in the activated graphene membrane, and the through holes are immersed in a coupling agent solution; Adhesive is used to stack and bond the impregnated graphene films, and then pressed and cured to obtain a prefabricated graphene thermal conductive pad; Coating resin on the outer surface of the prefabricated graphene thermal conductive pad to form a solidified layer; Cutting the prefabricated graphene thermally conductive gasket into sheets along the stacking direction of the graphene film, and polishing the cut surface; The solidified layer in the sheet material which is perpendicular to the stacking direction of the graphene film is removed to obtain the target high-strength and high-thermal-conductivity graphene thermally conductive gasket.

6. The preparation method according to claim 5, characterized in that: The concentration of the potassium hydroxide solution is 0.1%-10%, and the number of coatings is 1-10 times.

7. The preparation method according to claim 6, characterized in that: The temperature of the high temperature activation is 200-600° C., and the time of the high temperature activation is 5-20 minutes.

8. The preparation method according to claim 6, characterized in that: The concentration of the coupling agent is 0.01%-5%, the viscosity of the coupling agent is 5-50 mPa.s, and the immersion time is 10-60 minutes.

9. The preparation method according to claim 8, characterized in that: The coupling agent includes one or more of silane coupling agent, titanate coupling agent, aluminate coupling agent, phosphate coupling agent, borate coupling agent, chromium complex and coupling agents of higher fat, acid, alcohol and ester.

10. The preparation method according to claim 5, characterized in that: The polishing method includes one or more of chemical etching, water polishing, vibration polishing, ultrasonic polishing and dry polishing.

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