KR102467418B1 - Graphite composite material, manufacturing method thereof, and electronic control assembly for car including the same - Google Patents

Abstract

A graphite composite material is provided. The graphite composite material according to the present invention is implemented by including a graphite substrate including a matrix, graphite composites dispersed on the matrix and nanometal particles bonded to the surface of the graphite, and a protective coating layer formed on at least one surface of the graphite substrate do. According to this, by including the graphite substrate, there is an effect of improving heat dissipation characteristics and at the same time exhibiting an electromagnetic wave shielding effect. In addition, since the present invention includes a protective coating layer formed on at least one surface of the graphite substrate, peeling between graphite layers can be prevented from occurring.

Description

Graphite composite material, manufacturing method thereof, and electronic control assembly for a vehicle including the same

The present invention relates to a graphite composite material, and more particularly, to a graphite composite material that exhibits heat dissipation and electromagnetic wave shielding effects and has excellent heat dissipation characteristics, a manufacturing method thereof, and an electronic control assembly for a vehicle including the same.

Recently, with the rapid development of electronic and communication technologies, it has become possible to manufacture miniaturized and highly integrated devices by condensing unit circuit elements having various functions in a narrow space. However, between adjacent circuit elements in such a miniaturized and highly integrated device, the life of the device is shortened or the characteristics are deteriorated due to heat generated from each circuit device. In addition, due to mutual interference of electromagnetic waves generated from each circuit element, a problem of electromagnetic wave disturbance occurs, such as causing a malfunction of a device. It has been continuously reported that when a device that generates electromagnetic waves and heat is used for a long time, it raises the temperature of the user's biological tissue cells, thereby weakening the immune function or adversely affecting the human body, such as genetic modification. Accordingly, the need for heat dissipation and electromagnetic wave shielding to prevent the influence of electromagnetic waves on the human body has been further emphasized in recent years.

On the other hand, the electronic control unit (hereinafter referred to as ECU) generally used in vehicles receives various sensors such as oxygen sensor, air flow sensor, water temperature sensor, crank angle sensor, motor position sensor, atmospheric pressure sensor, etc. It plays a role of electronically controlling the driving of each part of the vehicle by receiving the signal of However, as high heat and electromagnetic waves are generated from a plurality of circuit elements mounted therein, for example, field effect transistors, the electronic control unit is applied to a material capable of dissipating heat generated from the circuit elements and shielding electromagnetic waves. development is urgently needed.

In order to solve this problem, recently, aluminum, copper, and alloy materials thereof are heated and melted at a high temperature, and then molding materials for heat dissipation and electromagnetic wave shielding manufactured by extruding using a mold having a certain shape are widely used. In the case of aluminum, copper, or alloy materials thereof, there is a problem in that it is difficult to express a desired level of heat dissipation performance because the thermal diffusivity is low and the heat dissipation performance to the outside of the air is significantly poor. In addition, in the case of aluminum, copper, and alloy materials thereof, it is difficult to achieve an electromagnetic wave shielding effect, so a separate electromagnetic wave shielding member must be included in the device, making it difficult to reduce the size or thickness of the device.

KR 10-0744271 B

The present invention has been devised in view of the above points, and the purpose of the present invention is to provide a graphite composite material that exhibits an electromagnetic wave shielding effect and a method for manufacturing the same, as well as excellent heat dissipation characteristics to the outside such as the atmosphere due to a remarkably high thermal diffusion index. have.

Another object of the present invention is to provide a graphite composite material capable of preventing delamination of graphite from occurring due to external conditions or preventing separation of graphite from a substrate and a manufacturing method thereof.

Another object of the present invention is to provide a graphite composite material capable of increasing the content of graphite and electromagnetic wave shielding material included in the heat dissipation composite material and a manufacturing method thereof.

Another object of the present invention is to provide a graphite composite material exhibiting excellent heat dissipation characteristics and electromagnetic wave shielding effect when applied to a vehicle electronic control unit, a manufacturing method thereof, and a vehicle electronic control assembly including the same.

The graphite composite material according to the present invention includes a graphite substrate including a matrix and graphite composites dispersed on the matrix and having nanometal particles bonded to the surface of the graphite; and a protective coating layer formed on at least one surface of the graphite substrate.

According to an embodiment of the present invention, the nanometal particles may be crystallized nanoparticles.

In addition, in order to improve interfacial properties between the matrix and the graphite composites, the graphite composites may further include a polydopamine layer coated on the nanometal particles.

In addition, the graphite composites may be included in an amount of 60 to 80% by weight in the graphite substrate.

In addition, the thickness of the polydopamine layer may be 5 ~ 1000nm.

In addition, the nanometal may include at least one selected from the group consisting of Ni, Si, Ti, Cr, Mn, Fe, Co, Cu, Sn, In, Pt, Au, and Mg.

In addition, the protective coating layer may be formed from a protective coating layer forming composition containing an epoxy resin.

In addition, the protective coating layer-forming composition may further include a carbon-based filler for improving thermal diffusion to the outside.

In addition, the carbon-based filler is selected from the group consisting of single-walled carbon nanotubes, double-walled carbon nanotubes, multi-walled carbon nanotubes, graphene, graphene oxide, graphene nanoplates, graphite, carbon black, and carbon-metal composites It may include at least one that is.

In addition, the protective coating layer forming composition may further include a physical property enhancing component for improving heat dissipation and adhesion.

In addition, the physical property enhancing component may include a silane-based compound.

In addition, the silane-based compound is 3-[N-anyl-N-(2-aminoethyl)]aminopropyltrimethoxysilane, 3-(N-anyl-N-glycidyl)aminopropyltrimethoxysilane, 3-(N-anyl-N-methacrylonyl]aminopropyltrimethoxysilane, 3-glycidyl oxypropylmethylethoxysilane, N,N-Bis[3-(trimethoxycinyl)propyl] Methacrylamide, γ-glycidoxytrimethyldimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxypropylmethylmethoxysilane, Beta(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, heptadecafluorodecytrimethoxysilane, 3- methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltris(trimethylsiloxy)silane, methyltris(dimethyloxyoxy)silane, 3-aminopropyltriepoxy silane, 3-mercaptopropyltrimethoxy silane and It may include at least one selected from the group consisting of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane.

In addition, the protective coating layer may be formed from a protective coating layer forming composition including a coating layer forming component including an epoxy resin, a carbon-based filler, and a physical property enhancing component for improving heat dissipation and adhesion including a silane-based compound.

In addition, the method for producing a graphite composite material according to the present invention includes the steps of preparing a graphite substrate by injection molding a graphite substrate-forming composition including a preparation matrix forming component and a graphite composite in which nano-metal particles are bonded to the surface of graphite, and the graphite and forming a protective coating layer on at least one surface of the substrate.

According to one embodiment of the present invention, the graphite composites may further include a polydopamine layer coated on the nanometal particles.

In addition, the poly-dopamine layer may be formed by dipping the graphite composite into an aqueous solution of dopamine.

In addition, in the dipping step, the pH of the dopamine aqueous solution may be 8 to 14, and the dopamine concentration may be 0.1 to 5 mg/mL.

In addition, the protective coating layer is formed by applying a protective coating layer-forming composition to at least one surface of a substrate, and the protective coating layer-forming composition may include a coating layer-forming component, a carbon-based filler, and a physical property enhancing component for improving heat dissipation and adhesion. have.

In addition, the carbon-based filler may be included in an amount of 0.1 to 30% by weight in the composition for forming the protective coating layer.

In addition, 0.01 to 20 parts by weight of a physical property enhancing component may be included based on 100 parts by weight of the carbon-based filler.

In addition, a method for manufacturing a graphite composite material according to another aspect of the present invention includes a graphite composite in which crystallized nanometal particles are bonded to the surface of graphite and a graphite-nanometal-polymer comprising a polymer resin layer formed on the graphite composite preparing the composites, preparing a graphite substrate by combining the polymer resin layers of the graphite-nanometal-polymer composites, and forming a protective coating layer on at least one surface of the graphite substrate.

According to one embodiment of the present invention, bonding between the polymer resin layers may be performed by applying any one or more of heat, light and pressure.

An electronic control assembly for a vehicle according to the present invention includes a printed circuit board, at least one circuit element disposed on the printed circuit board, and disposed surrounding the circuit element on the printed circuit board, the present invention for heat dissipation and electromagnetic wave shielding of graphite composites.

According to the present invention, by including a graphite substrate including a graphite composite, there is an effect of improving heat dissipation characteristics and at the same time exhibiting an electromagnetic wave shielding effect.

In addition, since the present invention includes a protective coating layer formed on at least one surface of the graphite substrate, it is possible to prevent separation between layers due to external conditions of graphite or separation of graphite from the substrate.

In addition, since the graphite composites of the present invention include the polydopamine layer coated on the nanometal particles, the content of the heat dissipation material and the electromagnetic wave shielding material included in the graphite composite material can be increased.

In addition, when the present invention is applied to a vehicle electronic control unit, it is possible to improve the electrical characteristics and extend the lifespan of the vehicle electronic control unit by dissipating heat generated from circuit elements and shielding electromagnetic waves.

1 is a cross-sectional view of a graphite composite material according to an embodiment of the present invention.

Hereinafter, in order to explain the present invention in more detail, preferred embodiments according to the present invention will be described in more detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Like reference numbers indicate like elements throughout the specification.

A method for manufacturing a graphite composite material according to an embodiment of the present invention includes the steps of preparing a graphite substrate by injection molding a graphite substrate-forming composition including a graphite composite in which nano-metal particles are bonded to a surface of graphite and a matrix-forming component; and and forming a protective coating layer on at least one surface of the graphite substrate.

In the step of preparing the graphite substrate, the graphite substrate-forming composition includes a matrix-forming component and a graphite composite.

The matrix forming component may be a polymer resin. The polymer resin may include at least one selected from the group consisting of thermosetting resins and thermoplastic resins. The thermosetting resin may include at least one selected from the group consisting of an epoxy-based resin, a urethane-based resin, a melamine-based resin, and a polyimide-based resin, and the thermoplastic resin may include a polycarbonate-based resin, a polystyrene-based resin, and a polysulfone-based resin. At least one selected from the group consisting of resin, polyvinyl chloride-based resin, polyether-based resin, polyacrylate-based resin, polyester-based resin, polyamide-based resin, cellulose-based resin, polyolefin-based resin, and polypropylene-based resin can include

When the graphite composite is a composite in which nano-metal particles are bonded to the surface of graphite, it can be selected and used regardless of a specific bonding method, the content of graphite and nano-metal particles, and the type of nano-metal particles. However, preferably, the nanometal particle may be a conductive metal capable of exhibiting an electromagnetic wave shielding effect. The nanometal particle may be prepared by including at least one selected from the group consisting of Ni, Si, Ti, Cr, Mn, Fe, Co, Cu, Sn, In, Pt, Au, and Mg. In addition, although the present invention is not particularly limited to the method for preparing the graphite composite, as an example, first, a graphite-nanometal particle mixture is prepared by mixing graphite and nanometal particles. At this time, the mixing ratio of the nanometal particles and the graphite can be arbitrarily set depending on the purpose of use, but in the present invention, since the nanometal particles exist at a high density on the surface of the graphite, it is preferably contained in an amount of 20 to 50 wt% relative to the total weight. Mix. Thereafter, plasma is applied to the graphite-nanometal particle mixture to vaporize the nanometal particles. Thereafter, a quenching gas is injected into the vaporized nanometal particles to condense or rapidly cool the vaporized nanometal particles. Accordingly, growth of the vaporized nanometal particles is suppressed, and the nanometal particles are crystallized on the surface of the graphite to form a graphite-nanometal particle complex. In the graphite composite, the nanometal particles may be included in an amount of 20 to 50 wt% with respect to the graphite, and may be bonded to the surface of the graphite in the form of crystals having an average particle diameter of 10 to 200 nm. In addition, the nanometal particles may have a surface area range of 30 to 70 area % with respect to the graphite composite.

Thereafter, a polydopamine layer may be further formed on the nanometal particles of the graphite-nanometal particle composite. The poly-dopamine layer may be formed by dipping the graphite-nanometal particle complex into an aqueous solution of dopamine. In this case, when a basic dopamine aqueous solution is used as the dopamine aqueous solution, dopamine reacts spontaneously under oxidizing conditions and is polymerized on the nanometal particles of the graphite-nanometal particle composite to form a polydopamine layer. Therefore, a separate firing process is not required, and the addition of an oxidizing agent is not particularly limited, but oxygen gas in the air can be used as an oxidizing agent without adding an oxidizing agent.

The dipping time determines the thickness of the coating layer. In the case of using an aqueous solution of dopamine prepared by dissolving dopamine to a concentration of 0.1 to 5 mg/mL in a basic Tris buffer solution of pH 8 to 14, a coating layer with a thickness of 5 to 100 nm is formed. To do this, it is preferable to dipping the graphite composite for about 0.5 to 24 hours.

At this time, even if graphite is dipped in dopamine aqueous solution, a dopamine coating layer is not formed on the surface, but a polydopamine layer is formed on the surface of the graphite-nanometal particle composite by the nanometal particles bonded to the graphite surface. The polydopamine layer thus formed improves interface properties between a matrix-forming component and the graphite composite, which will be described later. Therefore, it is possible to form a graphite substrate in the form of a sheet even if a small amount of the matrix forming component is included. Accordingly, the content of the graphite composite in the graphite substrate may be increased. In addition, when the polydopamine layer is coated on the graphite composite, dispersibility in an organic solvent is improved. Accordingly, when the graphite substrate-forming composition to be described later includes an organic solvent, the graphite composite is uniformly dispersed in the graphite substrate-forming composition. Accordingly, the graphite composite may be uniformly distributed in the graphite substrate formed from the graphite substrate-forming composition.

In addition, the graphite substrate-forming composition includes a leveling agent, a pH adjusting agent, an ion trapping agent, a viscosity adjusting agent, a thixotropy imparting agent, an antioxidant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, a colorant, a dehydrating agent, a flame retardant, and an antistatic agent. One type or two or more types of various additives such as, anti-mold, antiseptic, and the like may be added. The various additives described above may be those known in the art and are not particularly limited in the present invention. In addition, the coating layer forming component may further include a solvent. Depending on the selected adhesive component, a suitable solvent can be selected, and the present invention is not particularly limited thereto. As the solvent, any solvent capable of properly dissolving each component can be used. At least one selected from the group consisting of an aqueous solvent, an alcohol solvent, a ketone solvent, an amine solvent, an ester solvent, an amide solvent, a halogenated hydrocarbon solvent, an ether solvent, and a furan solvent may be used.

The graphite substrate-forming composition may be manufactured into a graphite substrate by injection molding. When the substrate is manufactured through injection molding, the process can be simplified because it is possible to manufacture the graphite substrate in a desired shape without a separate firing process. As described above, when the polydopamine layer is formed on the nanometal particles of the graphite-composite, the graphite composites may be included in an amount of 60 to 80% by weight in the graphite substrate.

On the other hand, the graphite substrate is prepared by preparing graphite-nanometal-polymer composites including a polymer resin layer formed on the graphite composite and pressing between the polymer resin layers of the graphite-nanometal-polymer composites to prepare a graphite substrate It can be prepared including the step of doing. The polymer resin may include the same material as the matrix forming component described above.

The polymer resin layer may be formed of a polymer resin layer forming composition containing the polymer resin on the surface of the graphite composite, and a method of adding a known polymer resin layer forming composition to the surface of the graphite composite, which is the coated surface, is limited It can be used without, as non-limiting examples thereof, blade coating, flow coating, casting, printing method, transfer method, brushing, dipping or spraying ), etc., the polymer resin layer forming composition described above may be coated on the surface of the graphite-nanometal particle composite.

Compression between the polymer resin layers is not particularly limited, but compression may be performed within a pressure or temperature range capable of bonding between the polymer resin layers. At this time, compression between the polymer resin layers may be performed by applying any one or more of heat and pressure.

Thereafter, a step of forming a protective coating layer on at least one surface of the graphite substrate manufactured by the above-described method is performed.

The protective coating layer may be formed through a protective coating layer forming composition.

The protective coating layer forming composition may include a coating layer forming component, a carbon-based filler, and a physical property enhancing component for improving heat dissipation and adhesion.

The coating layer forming component may be a coating layer forming component known in the art and is not particularly limited in the present invention. However, in order to simultaneously achieve excellent adhesion performance between the graphite substrate and the carbon-based filler and coating layer-forming components described later and improved heat dissipation performance due to improved compatibility with the carbon-based filler, the coating layer-forming component may include an epoxy resin. In addition, a curing agent for curing the epoxy resin may be included as a coating layer forming component. As the epoxy resin, an epoxy resin known in the art may be used, and the specific type is not particularly limited, and may be selected and used differently depending on the purpose. However, preferably, the epoxy resin is glycidyl ether type epoxy resin, glycidyl amine type epoxy resin, glycidyl ester type epoxy resin, linear aliphatic type epoxy resin, cyclo aliphatic type epoxy It may include at least one selected from the group consisting of resins, heterocyclic-containing epoxy resins, substituted epoxy resins, naphthalene-based epoxy resins, and derivatives thereof.

Specifically, the glycidyl ether type epoxy resin includes glycidyl ether of phenols and glycidyl ether of alcohols, and the glycidyl ethers of phenols include bisphenol A type, bisphenol B type, bisphenol AD type, and bisphenol Bisphenolic epoxies such as S-type, bisphenol F-type and resorcinol, phenol novolac epoxies, phenolic novolacs such as aralkylphenol novolacs, terpenephenol novolacs, and o-cresol novolacs There are cresol novolak-type epoxy resins like epoxy, etc. These can be used individually or in combination of 2 or more types.

As the glycidyl amine-type epoxy resin, diglycidylaniline, tetraglycidyldiaminodiphenylmethane, N,N,N',N'-tetraglycidyl-m-xylylenediamine, 1,3 -Bis(diglycidylaminomethyl)cyclohexane, triglycidyl-m-aminophenol and triglycidyl-p-aminophenol having both structures of glycidyl ether and glycidylamine. Two or more types can be used together.

The glycidyl ester type epoxy resin may be an epoxy resin based on hydroxycarboxylic acids such as p-hydroxybenzoic acid and β-hydroxynaphthoic acid and polycarboxylic acids such as phthalic acid and terephthalic acid, alone or in combination of two or more. can do. As the linear aliphatic type epoxy resin, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, cyclohexanedimethanol, glycerin, trimethylolethane, thirimethylolpropane, pentaerythrol, dodecahydrobisphenol A , dodecahydrobisphenol F, ethylene glycol, propylene glycol, polyethylene glycol, or glycidyl ether by polypropylene glycol, etc., and may be used alone or in combination of two or more.

As the alicyclic epoxy resin, epoxy resins containing compounds represented by the above-described formulas 1 to 4 may be used singly or in combination of two or more.

The naphthalene-based epoxy resin includes 1,2-diglycidylnaphthalene, 1,5-diglycidylnaphthalene, 1,6-diglycidylnaphthalene, 1,7-diglycidylnaphthalene, and 2,7-diglycidylnaphthalene. It may be an epoxy resin having a naphthalene skeleton, such as diglycidyl naphthalene, triglycidyl naphthalene, and 1,2,5,6-tetraglycidyl naphthalene, and may be used alone or in combination of two or more.

In addition to those listed above, it may be triglycidyl isocyanurate, an epoxy resin having an epoxycyclohexane ring in the molecule obtained by oxidizing a compound having a plurality of double bonds in the molecule, and the like.

In addition, the type of curing agent included in the coating layer forming component together with the epoxy resin may be different depending on the specific type of the selected epoxy resin, and the specific type may use a curing agent known in the art, preferably a polyvalent hydride. It may include any one or more of hydroxy compounds, aliphatic amines, aromatic amines, acid anhydrides, and latent curing agents.

Specifically, as non-limiting examples of the aromatic amines, metaphenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, azomethylphenol, and the like may be used alone or in combination. In addition, as non-limiting examples of the aliphatic amines, diethylenetriamine, triethylenetetramine, etc. may be used alone or in combination. In addition, as non-limiting examples of the acid anhydride-based curing agent, polyhydric hydroxy compounds such as the phenol novolak resin, orthocresol novolak resin, naphthol novolak resin, and phenol aralkyl resin, and modified products thereof, anhydrous Phthalic acid, maleic anhydride, hexahydrophthalic anhydride, pyromellitic anhydride, etc. may be used alone or in combination, and non-limiting examples of the latent curing agent include dicyandiamide, imidazole, BF 3 -amine complex, guanidine A derivative etc. can be used individually or in combination of 2 or more types.

In addition, among curing agents for epoxy resins, a heat-curable curing agent that is liquid at room temperature or a latent curing agent such as dicyandiamide that is multifunctional and may be added in a small amount in an equivalent amount may be used as the curing agent.

As described above, the curing material included in the above-described components for forming the coating layer may be included in an amount of 5 to 300 parts by weight based on 100 parts by weight of the epoxy resin, and through this, desired levels of physical properties and adhesive performance may be expressed.

In addition, the coating layer forming component may further include a curing accelerator in addition to the above-described epoxy resin and curing agent. The curing accelerator serves to adjust the curing speed or physical properties of the cured product, and a known curing accelerator may be selected and used according to the type of the selected curing agent. As non-limiting examples thereof, amines and imida Sols, organic phosphines, and Lewis acid hardening accelerators may be used. An example of the use of the curing accelerator is when an amine-based curing agent is used, for example, an imidazole-based curing accelerator may be used in combination. However, the present invention is not limited to this example of use.

In addition, the components for forming the coating layer include a leveling agent, a pH adjusting agent, an ion trapping agent, a viscosity adjusting agent, a thixotropy imparting agent, an antioxidant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, a colorant, a dehydrating agent, a flame retardant, and an electrification agent. One type or two or more types of various additives, such as an inhibitor, a fungicide, and an antiseptic, may be added. The various additives described above may be those known in the art and are not particularly limited in the present invention. In addition, the coating layer forming component may further include a solvent. Depending on the selected adhesive component, a suitable solvent can be selected, so this is not particularly limited in the present invention, and any solvent that allows appropriate dissolution of each component can be used as the solvent, for example, water At least one selected from the group consisting of an aqueous solvent, an alcohol solvent, a ketone solvent, an amine solvent, an ester solvent, an amide solvent, a halogenated hydrocarbon solvent, an ether solvent, and a furan solvent may be used.

The carbon-based filler may be used without limitation when it contains carbon in its material, and a carbon-based material known in the art may be used. By including the carbon-based filler in the protective coating layer-forming composition, heat dissipation properties of the protective coating layer are improved so that heat dissipated from the graphite substrate can be smoothly discharged to the outside through the protective coating layer. In addition, since the carbon-based filler contains carbon in the same way as the graphite substrate, interfacial properties between the graphite substrate and the protective coating layer may be improved. In addition, the shape and size of the carbon-based filler are not limited, and may be porous or non-porous in structure, and may be selected differently depending on the purpose, and are not particularly limited in the present invention. However, preferably, in order to express excellent heat dissipation performance, single-walled carbon nanotubes, double-walled carbon nanotubes, multi-walled carbon nanotubes, graphene, graphene oxide, graphene nanoplates, graphite, carbon black, and carbon-metal composites It may include one or more types from the group consisting of, and more preferably, carbon black may be included as the main material of the carbon-based filler.

In addition, in the case of the carbon-based filler, a carbon-based filler whose surface is modified with a functional group such as a silane group, an amino group, an amine group, a hydroxyl group, or a carboxyl group may be used. In this case, the functional group may be directly bonded to the surface of the carbon-based filler. Alternatively, it may be indirectly bonded to the carbon-based filler through a substituted or unsubstituted aliphatic hydrocarbon having 1 to 20 carbon atoms or a substituted or unsubstituted aromatic hydrocarbon having 6 to 14 carbon atoms. In addition, it may be a core-shell type filler in which the carbon-based material serves as a core or a shell and a different material constitutes the shell or core.

The carbon-based filler may be included in the protective coating layer-forming composition in an amount of 0.01 to 90% by weight, preferably in an amount of 0.1 to 30% by weight, more preferably in an amount of 6 to 20% by weight, and even more preferably in an amount of 8 to 30% by weight. It may be included in 15% by weight, and if the carbon-based filler is included in 0.01% by weight of the protective coating layer forming composition, there may be a problem that the desired heat dissipation performance cannot be achieved, and if it exceeds 90% by weight, the adhesive performance There may be a problem that the carbon-based filler is detached during use due to a significant decrease in basic physical properties and durability.

Next, the physical property enhancing component included in the composition for forming a protective coating layer according to the present invention will be described.

The physical property enhancing component functions to improve durability by expressing more improved heat dissipation and simultaneously expressing excellent adhesiveness when the composition for forming a protective coating layer according to the present invention is coated on the graphite substrate. When the above-mentioned property-enhancing component is used together with the epoxy resin among the above-mentioned components for forming the coating layer and carbon black among the carbon-based fillers, synergistic action of the desired physical properties occurs, resulting in remarkable durability and heat dissipation. As a result, the surface of the conventional graphite substrate is modified or It enables improvement of physical properties that cannot be achieved by any coating method, and exhibits improved heat dissipation and adhesion even in graphite substrates with a very simple shape and small surface area or molded products made of organic compounds such as non-metals or plastics. can make it

According to a preferred embodiment of the present invention, the physical property enhancing component may include a silane-based compound. The silane-based compound may be used without limitation in the case of a compound commonly used as a silane coupling agent in the art, and as non-limiting examples thereof, amino silane coupling agent, epoxy silane coupling agent, ureido silane coupling agent, isocyanate silane coupling agent , A vinyl silane coupling agent, an acryl silane coupling agent, a ketimine silane coupling agent, etc. are mentioned, These silane coupling agents may be used individually or in combination of 2 or more types. In addition, the silane-based compound may further include a titanium coupling agent, an aluminum coupling agent, and the like.

The silane-based compound is preferably 3-[N-anyl-N-(2-aminoethyl)]aminopropyltrimethoxysilane, 3-(N-anyl-N-glycidyl)aminopropyltrimethoxysilane , 3-(N-anyl-N-methacrylonyl]aminopropyltrimethoxysilane, 3-glycidyloxypropylmethylethoxysilane, N,N-Bis[3-(trimethoxycinyl)propyl ]Methacrylamide, γ-glycidoxytrimethyldimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxypropylmethylmethoxysilane , beta(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, heptadecafluorodecytrimethoxysilane, 3 -Methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltris(trimethylsiloxy)silane, methyltris(dimethyloxyoxy)silane, 3-aminopropyltriepoxy silane, 3-mercaptopropyltrimethoxy silane and N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane.

In addition, the physical property enhancing component further includes a dispersant in the silane-based compound. As the dispersant, those known in the art may be used without limitation. However, polyester-based dispersing agents, polyphenylene ether-based dispersing agents; Polyolefin-based dispersants, acrylonitrile-butadiene-styrene copolymer dispersants, polyarylate-based dispersants, polyamide-based dispersants, polyamide-imide-based dispersants, polyarylsulfone-based dispersants, polyetherimide-based dispersants, polyethersulfone-based dispersants, poly phenylene sulfide-based dispersing agents and polyimide-based dispersing agents; Polyether ketone dispersant, polybenzoxazole dispersant, polyoxadiazole dispersant, polybenzothiazole dispersant, polybenzimidazole dispersant, polypyridine dispersant, polytriazole dispersant, polypyrrolidine dispersant, polydibenzofuran a polysulfone-based dispersing agent, a polyurea-based dispersing agent, a polyurethane-based dispersing agent, or a polyphosphazene-based dispersing agent, and the like, and these alone or a mixture or copolymer of two or more selected from these may be used.

The dispersant may preferably be included in the physical property enhancing component in an amount of 0.001 to 1000 parts by weight based on 100 parts by weight of the silane-based compound, and through this, it may be more advantageous to achieve desired physical properties.

In addition, the physical property enhancing component may further include a dispersion stabilizer, and the dispersion stabilizer may use one known in the art, so that the specific type is not limited in the present invention, and as a non-limiting example thereof, anionic Surfactants, cationic surfactants, nonionic surfactants, wetting agents or wettability improvers and the like can be used.

In addition, the physical property enhancing component may preferably be included in an amount of 0.01 to 20 parts by weight, more preferably 1 to 10 parts by weight, and even more preferably 2 to 6 parts by weight, based on 100 parts by weight of the carbon-based filler. . If the physical property enhancing component does not satisfy the above range, there may be a problem in that desired physical properties such as durability through improved heat dissipation and adhesiveness cannot be achieved at the desired level at the same time.

The protective coating layer may be used without limitation as long as it is a method of adding the protective coating layer-forming composition to the surface to be coated on the surface of the graphite substrate, and non-limiting examples thereof include blade coating, flow coating, The above-described protective coating layer forming composition may be coated on the surface of the graphite substrate by a method such as casting, printing, transfer, brushing, dipping, or spraying. At this time, the viscosity of the composition for forming the protective coating layer may be 1 to 100,000 cps .

Referring to FIG. 1, a graphite composite material according to an embodiment of the present invention includes a matrix 10 and graphite composites 20 dispersed on the matrix and having nanometal particles bonded to the surface of the graphite. A substrate 100 and a protective coating layer 200 formed on at least one surface of the graphite substrate 100 are included. The graphite substrate 100 may exhibit both heat radiation and electromagnetic wave shielding effects as nanometal particles having electromagnetic wave shielding characteristics are bonded to the graphite surface having excellent heat radiation characteristics. In addition, since the protective coating layer 200 formed on at least one surface of the graphite substrate 100 is included, peeling between layers of the graphite may be prevented, and separation of the graphite composite from the matrix may be prevented.

At this time, the thickness of the graphite substrate may be 0.1 ~ 100,000 ㎛. When the thickness of the graphite substrate is less than 0.1 μm, heat dissipation properties may be deteriorated, and when the thickness of the graphite substrate exceeds 100,000 μm, thinning is difficult.

In addition, the thickness of the protective coating layer may be 0.1 ~ 1000 ㎛ . When the thickness of the protective coating layer is less than 0.1 μm, the probability of separation of the graphite composite in the graphite substrate increases, and when the thickness of the protective coating layer exceeds 1000 μm, thinning is difficult.

Meanwhile, the electronic control assembly for a vehicle according to the present invention will be described.

The electronic control assembly for a vehicle includes a printed circuit board, at least one circuit element disposed on the printed circuit board, and disposed surrounding the circuit element on the substrate according to an embodiment of the present invention for heat dissipation and electromagnetic wave shielding. Including graphite composites. In this case, the circuit element may be an electric field effect transistor.

In the above, the present invention has been described in detail with preferred embodiments, but the present invention is not limited by the above embodiments, and various modifications are made by those skilled in the art within the technical spirit and scope of the present invention. and change is possible.

10: matrix 20: graphite composite
100: graphite substrate 200: protective coating layer

Claims (23)

A graphite substrate containing 60 to 80% by weight of a matrix and graphite composites in which nanometal particles dispersed on the matrix and having a polydopamine layer formed on the surface of the graphite are bound; and
A graphite composite material for shielding electromagnetic waves comprising: a protective coating layer formed on an outer surface of the graphite substrate to a thickness of 0.1 to 1000 μm in order to prevent the separation of the graphite layers and the separation of the graphite composite from the matrix.
delete delete According to claim 1,
The polydopamine layer has a thickness of 5 to 1000 nm, a graphite composite material for shielding electromagnetic waves.
According to claim 1,
The graphite composites further include a polymer resin layer formed on graphite and nanometal particles.
The method of claim 1, wherein the protective coating layer
It is formed from a protective coating layer forming composition comprising a coating layer forming component including an epoxy resin, a carbon-based filler, and a physical property enhancing component for improving heat dissipation and adhesion including a silane-based compound,
The carbon-based filler is included in the protective coating layer forming composition in an amount of 0.1 to 30% by weight,
A graphite composite material for shielding electromagnetic waves containing 0.01 to 20 parts by weight of a physical property enhancing component based on 100 parts by weight of the carbon-based filler.
Preparation of a graphite substrate containing 60 to 80% by weight of the graphite composites in a matrix by injection molding a graphite substrate-forming composition comprising graphite composites in which a matrix forming component and nanometal particles having a polydopamine layer formed on the surface of graphite are bonded thereto doing; and
Forming a protective coating layer to a thickness of 0.1 to 1000 μm on an outer surface of the graphite substrate in order to prevent the separation of the graphite layers and the separation of the graphite composite from the matrix. Method for producing a graphite composite material for shielding electromagnetic waves.
delete According to claim 7,
The poly-dopamine layer is a method of manufacturing a graphite composite material for shielding electromagnetic waves formed by dipping the graphite composite in an aqueous solution of dopamine.
According to claim 9,
The pH of the dopamine aqueous solution is 8 to 14, and the dopamine concentration is 0.1 to 5 mg / mL. Method for producing a graphite composite material for shielding electromagnetic waves.
The method of claim 7, wherein the protective coating layer
It is formed through a protective coating layer forming composition comprising a coating layer forming component including an epoxy resin, a carbon-based filler, and a physical property enhancing component for improving heat dissipation and adhesion including a silane-based compound,
The carbon-based filler is included in the protective coating layer forming composition in an amount of 0.1 to 30% by weight,
Method for producing a graphite composite material for electromagnetic wave shielding containing 0.01 to 20 parts by weight of a physical property enhancing component based on 100 parts by weight of the carbon-based filler.
printed circuit board;
at least one circuit element disposed on the printed circuit board; and
An electronic control assembly for a vehicle comprising the graphite composite material for heat dissipation and electromagnetic wave shielding according to any one of claims 1, 4 to 6, disposed on the printed circuit board to surround the circuit element.

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