KR20140080473A

KR20140080473A - Heat releasing composite and manufacturing method for the same

Info

Publication number: KR20140080473A
Application number: KR1020140067770A
Authority: KR
Inventors: 고정호; 신관우
Original assignee: 지앤씨테크(주)
Priority date: 2014-06-03
Filing date: 2014-06-03
Publication date: 2014-06-30
Also published as: KR101532026B1; WO2015186959A1

Abstract

The present invention relates to a heat-radiation metal organic composite material and a manufacturing method thereof, which provides a composite material of metal-polymer having increased binding force by including a step of manufacturing a metal material; a step of manufacturing reactive polymer; and a metal material-reactive polymer mixing step of mixing the metal material and the reactive polymer to make the metal material and the reactive polymer have a mutual covalent bond or an ion bond structure on an interface where the metal material is in contact with the reactive polymer.

Description

TECHNICAL FIELD The present invention relates to a composite material and a manufacturing method thereof,

TECHNICAL FIELD The present invention relates to a composite material and a manufacturing method thereof, and more particularly, to a composite material having a structure in which a metal and a polymer are covalently bonded or ion-bonded to each other, and a manufacturing method thereof.

Generally, in operation of an electronic device, various electronic parts are accompanied by heat generation due to the characteristics of the material itself and electrical resistance, and the heat generation of the electronic parts deteriorates the performance of the electronic parts and causes malfunction of the electronic devices. Therefore, as a solution to the heat generation problem of the electronic device, a heat-sink is introduced into the electronic device in order to release heat to the outside of the electronic device.

The heat dissipator is mainly made of a metal having high thermal conductivity, for example, a metal such as aluminum (Al) or copper (Cu), and is manufactured in the form of a sheet or a plate. And transmits heat discharged from the component to the outside to discharge the heat.

However, it is easy to fabricate and dispose a heat radiator because the surface area of the heat dissipator made of the single metal is relatively small. However, the heat dissipator has a relatively large size for electronic devices used for street lamps and tunnels, In the case of a device, since the amount of heat generated is large, the size of the heat sink is increased when the heat sink is made of Al metal, the weight of the final heat sink is increased, and the mold required for die casting is required according to the desired size. Thereby causing a problem in that the manufacturing cost is increased.

Conventionally, a method of fabricating a heat sink for reducing the weight in a state of maintaining thermal conductivity includes the steps of dispersing metal powder in a base made of a polymer such as plastic, or dispersing metal nanotube (CNT) The heat transfer plastic was prepared by injecting a mixture with increased heat transfer and used as a heat sink.

However, such a heat transfer plastic has to increase the amount of heat transfer materials (metal particles, carbon nanotubes, etc.) dispersed in the base in order to increase the heat transfer. However, since the amount of heat transfer material is increased, And the strength of the heat transfer material is reduced due to the bonding force between the heat transfer material and the heat transfer material.

Further, by increasing the amount of the heat transfer material to increase the heat transfer characteristic, the weight can be reduced relative to the conventional heat radiator, but the effect of reducing the cost is insufficient.

KR 2013-0116992 A1

The present invention provides a composite material in which molecules of a metal and a polymer are covalently bonded or ion-bonded to each other, and a method of manufacturing the composite material.

The present invention provides a composite material capable of maintaining thermal conductivity of a heat discharger and capable of reducing specific gravity, and a method for manufacturing the composite material.

The present invention provides a composite material and a method of manufacturing the same that can be applied to various fields.

In the composite material according to the embodiment of the present invention, the metal and the reactive polymer are mixed with each other, and the interface between the mixed metal and the reactive polymer has a structure in which the metal and the reactive polymer molecule are mutually covalently bonded or ionically bonded .

The metal may be surface-modified by a metal pretreatment agent so that the energy level between the metal atoms is reduced.

The metal may include a first metal and a second metal having different average diameters of the atomized particles, and the average diameter (r ₁ ) of the first metal may be larger than the average diameter (r ₂ ) of the second metal .

The average diameter (r ₁ ) of the first metal may be 50 nm to 50 탆.

The metal may be one or more of an aluminum or aluminum alloy (an alloy of iron, silicon carbide, manganese, magnesium or the like with an aluminum weight ratio of 70% or more), a copper or copper alloy series, a magnesium or magnesium alloy series, (Al ₂ O ₃ ), iron oxide, mineral powders containing a metal component (Na, Al, Si ₂ O ₆ ), aluminum silicate (mica, mica stone), aluminum hydroxide Al (OH) _3), the metal component comprising a magnesium hydroxide (Mg (OH) _2), calcium carbonate (CaCO _3), barium sulfate, magnesium oxide _{(MgO), Mg3 (Si 4} O 10) (OH) 2 One or more of ceramic or metal salts may be selected and used.

Wherein the reactive polymer has a carbon chain as a main chain structure and a base polymer capable of introducing a polar group into the main chain or side chain chain and a modified polymer having a substituent group are graft copolymerized and polymer- Or may be surface-modified by a < / RTI >

The reactive polymer may further comprise a thermally conductive additive for the polymer.

The reactive polymer may be added in an amount of 3 to 30 wt% based on the total weight of the composite material.

The modified polymer may be contained in an amount of 0.1 to 20 wt% based on the total amount of the base polymer.

The structure in which the molecules of the metal and the molecules of the reactive polymer are mutually covalently bonded or ion-bonded is increased by the mixing pretreatment agent for increasing the reactivity at the interface between the metal and the reactive polymer, Can be promoted.

And a thermally conductive additive for mixing in the gap between the metal materials.

The thermally conductive additive for mixing may be added in an amount of 55 wt% or less based on the total amount of the reactive polymer.

The thermally conductive additive may be selected from the group consisting of gold, silver, copper and copper alloys, aluminum and aluminum alloy series, magnesium and magnesium alloys, iron and iron oxide or iron based alloys, magnesium hydroxide or aluminum hydroxide containing metals, Metal oxides, graphene, graphite, carbon fine powder or CNT based metals such as Al ₂ O ₃ , BeO ₂ , boron nitride, magnesium whisker, silicon carbide, silicon nitride, aluminum nitride, One or more of the mineral components including the component may be selected and used.

The surface of the thermally conductive additive may be coated with one or more selected from petroleum solvent, fatty acid oil, white oil, mineral oil, silicone oil, olefin wax, DTBT and glycol.

The method for manufacturing a heat dissipating metal organic composite material according to an embodiment of the present invention includes the steps of: preparing a metal; preparing a reactive polymer; mixing the metal and the reactive polymer to form a metal- And a reactive polymer incorporation step.

The metal-reactive polymer incorporation step increases the reactivity of the interface between the molecules of the metal and the molecules of the reactive polymer by mutual covalent bonding or ionic bonding, thereby preventing phase separation and introducing a mixing pretreatment agent for inducing uniform mixing, A mixing pretreatment step of performing a preliminary mixing process.

The step of preparing the metal may include a process of selecting and atomizing a single metal or two or more metals, and a surface modification process of modifying the surface of the selected metal to reduce energy levels of the metal atoms.

The step of preparing the reactive polymer includes graft copolymerizing a base polymer having a high molecular weight and a modified polymer having a substituent, a process of atomizing the copolymerized polymer, and a process of atomizing the polymerized polymer to facilitate interfacial bonding with the metal And a surface modification with a polymer pretreatment agent.

The step of preparing the reactive polymer may further include a step of incorporating the thermally conductive additive for the polymer.

The metal-reactive polymer incorporation step may further include incorporating a thermally conductive additive for mixing.

According to the composite material of the present invention and the manufacturing method thereof, it is possible to provide a metal-polymer composite material having increased bonding force through intermolecular covalent bonding or ionic bonding of different materials.

That is, the microparticles are mixed with a reactive polymer having a polar group and a substituent to induce an acid-base substitution reaction in the interfacial bonding process to form a substituted covalently bonded morphology. At this time, the metal is surface-modified by the metal pretreatment agent so that the energy level between the metal atoms is reduced, and the reactive polymer is surface-modified to promote interfacial bonding with the metal, so that the metal and the reactive polymer can be easily covalently bonded or ion- can do.

Accordingly, it is possible to exhibit a strong bonding force between a metal and a polymer or a strong bond due to ionic bonding, compared to a composite material produced by simple mixing of a metal and a polymer in the prior art. As a result, .

Accordingly, a heat dissipator can be manufactured at a reduced manufacturing cost compared with the case where a heat dissipator is made of only a metal, and the ratio or kind of the metal and the reactive polymer can be selected and used.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a model diagram showing a pre-reaction configuration of a composite material according to an embodiment of the present invention. FIG.
2 is a view for explaining a crystal of a metal according to an embodiment of the present invention.
3 is a flowchart illustrating a method of manufacturing a composite material according to an embodiment of the present invention.
Fig. 4 is a schematic view showing the structure of a composite material matrix according to the bonding strength between composites.
5 is a view for explaining the pre-treatment process of the metal of the present invention.
FIG. 6 is a diagram illustrating the covalent substitution bonding process of a metal interface and a reactive polymer according to an embodiment of the present invention.
FIGS. 7 and 8 are photographs showing a heat dissipating body specimen manufactured using a composite material according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be understood, however, that the invention is not limited to the disclosed embodiments, but is capable of other various forms of implementation, and that these embodiments are provided so that this disclosure will be thorough and complete, It is provided to let you know completely.

Throughout the specification, when an element is referred to as " comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise.

Hereinafter, a composite material and a manufacturing method thereof according to an embodiment of the present invention will be described with reference to FIGS. 1 to 8. FIG. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a model diagram showing a pre-reaction configuration of a composite material according to an embodiment of the present invention. FIG. 2 is a view for explaining a crystal of a metal according to an embodiment of the present invention. 3 is a flowchart illustrating a method of manufacturing a composite material according to an embodiment of the present invention. Fig. 4 is a schematic view showing the structure of a composite material matrix according to the bonding strength between composites. 4 (a) shows a structure of a composite material matrix showing an ideal morphology, and FIG. 4 (b) is a schematic diagram showing a structure of a composite material matrix having a binding force non-uniform morphology. 5 is a view for explaining the pre-treatment process of the metal of the present invention. FIG. 6 is a diagram illustrating the covalent substitution bonding process of a metal interface and a reactive polymer according to an embodiment of the present invention. FIGS. 7 and 8 are photographs showing a heat dissipating body specimen manufactured using a composite material according to an embodiment of the present invention.

In the composite material 1 according to the embodiment of the present invention, the metal 100 and the reactive polymer 200 are mixed with each other, and the interface between the metal 100 and the reactive polymer 200, The reactive polymer (200) molecules have mutually covalent or ionically bonded structures, thereby providing a thermally conductive matrix having increased bonding strength between dissimilar materials. In other words, the composite material 1 reduces the reaction enthalpy of the metal 100 and the metal 100, and forms a covalent bond and an ionic bond between different materials such as the reactive polymer 200 that induces an acid- It has strong rigidity, high strength and mechanical strength of metal, and chemical properties such as electrical insulation, chemical resistance, chemical resistance, weatherability, flame resistance and so on, which are composed of strong chemical interactio Can be realized.

The metal material (100) is a component for providing heat dissipation to the composite material (1) and is surface-modified by a metal pretreatment agent so that the energy level between the metal atoms is reduced. The metal 100 may be composed of a first metal 110 and a second metal 130 having different average diameters of the atomized particles.

The first metal 110 is for constituting a main basic morphology of the composite material 1 and is determined in consideration of economical efficiency of a molded product made of the composite material 1, The same or similar particle size with a small average grain size variation can be selected and used so that mutual stresses (uniform intermolecular attraction after bonding with the polymer) between the first metal 110 grain in the first metal 110 can be applied have. More specifically, particles having an average diameter of 50 nm to 50 占 퐉 may be used as the average diameter (r ₁ ) of the first metal 110. As the average diameter r ₁ decreases, the crystallinity of the morphology formed by the first metal 110 may become more dense. However, as the average diameter r 1 decreases, the cost increases, The cost of manufacturing the composite material 1 may be increased and the compatibility may be reduced. On the other hand, as the average diameter r ₁ increases, the space between the first metal members 110 (that is, the gap between the first metal members) increases, so that it is not easy for the free electrons between the metal members to easily move. Accordingly, the average diameter (r ₁ ) of the first metal 110 can be selected within the above range in consideration of a cost consumed in manufacturing the composite material 1, and the second metal 130 The average diameter r ₁ can be determined depending on the presence or absence of the injection of the gas. That is, the size of the first metal 110 may be selected according to the field to which the composite material 1 is applied and the desired strength of the ventilation hole made of the composite material 1. The first metal 110 may be selected from the group consisting of spherical, linear, and bulk types. When the first metal 110 is selected and used as a spherical shape, the metal 100 having an irregular surface may be used. The interfacial bonding can be facilitated more than when used.

The second metal material 130 is provided to fill the gap between the first metal materials 110 and the second metal material 130 is formed so as to be larger than the average diameter r ₁ of the first metal material 110 in order to fill the gap between the first metal materials 110. Can be selected and used to have a small average diameter (r ₂ ). In this case, the second metal 130 may be selected from the same or different materials as the metal selected as the first metal 110, and when a spherical material is used as in the first metal 110, And the mechanical bonding strength can be increased. Also, the second metal 130 is selected to have the same or similar particle size with a small average grain size variation so that mutual stresses (uniform intermolecular attraction after bonding with the polymer) between the grains can be applied Can be used. More specifically, the second metal 130 may have a diameter smaller than that of the first metal 110 to fill voids formed between the first metal 110 and one or more particles having different particle sizes . The second metal 130 may be charged with a metal having an average diameter r ₂ of at least one kind and the particle size relationship between the second metal 130 having a plurality of average diameter values may be all Have a smaller average diameter than the first metal (110), and the relationship of the mutual average diameters may be larger or smaller. For example, the second average diameter of the metal (130) (r ₂₎ is 50 ㎚ to 20 ㎛ average diameter (r ₂₎ the particle is used or having the first particle size selected from a metal (110) r _1/10 To r &_lt; 1/3 > can be selected and used. More specifically, the second metal 130 can be the size of the particles of r ₁ / r 6 to _1/4 of an average diameter (r ₁₎ is selected as the first metal 110 is selected. At this time, when the average diameter r ₂ of the second metal 130 has a particle size exceeding the range, it is not easy to fill the gap between the particles of the first metal 110, In the case of having a particle size, it may cause unevenness in the matrix. Accordingly, the second metal 130 may be selected and considered according to the selection of the first metal 110 within the above range.

On the other hand, when the average diameter (r ₁ ) of the selected first metal 110 is 1 μm or less, the second metal 130 may be selected from one or more metal or metal salt nanoparticles, .

For example, when the first metal 110 is selected as a particle having an average diameter r ₁ of 200 μm, a gap formed between the selected first metal 110 (for example, to fill the formation pore size 50㎛) has a second metal (130 a similar or the same size as the size of the air gap) may be selected to have an average diameter (r ₂₎ of 50 ㎛. When the second metal 130 is charged with a plurality of particle sizes, the second metal 130 may be selected to have a particle size of 1 μm or less. Thus, metal particles having a total of three particle sizes can be interfaced.

Such a metal material 100 may be selected with different metal materials and particle sizes depending on the field in which the composite material 1 is to be used. That is, the metallic material 100 is to provide thermal conductivity and durability in constituting the heat-dissipating composite material 1. The metal material 100 may be an aluminum or aluminum alloy alloy that is easily covalently bonded to the reactive polymer 200, (Al alloy having a weight ratio of aluminum of 70% or more and iron, silicon carbide, manganese, magnesium, etc.), copper or copper alloy, magnesium or magnesium alloy, iron or iron alloy (Al ₂ O ₃ ), iron oxide, or a mineral powder containing a metal component (Na, CaO, or the like) capable of interfacial bonding through covalent substitution bonds with the reactive polymer (200) Al, Si ₂ O ₆ ), aluminum silicate (mica), aluminum hydroxide (Al (OH) ₃ ), magnesium hydroxide (Mg (OH) ₂ ), wollastonite (CaSiO ₃ , Wollastonite), calcium carbonate , Bar Sulfide, magnesium oxide (MgO), talc _{(Mg 3 (Si 4 O 10} ) (OH) 2, Talc) can be selected individually or in combination of two or more of.

The metal 100 selected as described above can be pretreated with a metal pretreatment agent and then introduced into a synthesis with a reactive polymer 200 described later.

The metal pretreatment agent has a low bonding rate per mole because the structure of the covalent molecular structure formed at the interface is not stable or low in reactivity, or the molecules of the metal 100 and the molecules of the reactive polymer 200 are formed by repulsive force, The metal 100 may be introduced to induce expansion of the crystal, which is introduced to modify the surface to inhibit or prevent the formed matrix from being formed into a fragile structure. That is, the metal pretreatment agent may be added to induce a directionality in which the metal 100 and the reactive polymer 200 can react preferentially. If the metal 100 is not surface-modified by the metal pretreatment agent and the reactivity with the reactive polymer 200 is reduced, the metal 100 that is not interfaced with the metal 100 may be crushed or simply impregnated into the reactive polymer 200, It is not easy to realize the function of the covalent bond interface between the metal 100 and the reactive polymer 200 of the present invention. If the metal 100 and the reactive polymer 200 are mixed with the reactive polymer 200 without pre-treatment of the metal 100, the residual monomer remaining in the reactive polymer 200 without reacting with the metal 100 250), it causes non-uniformity of macroscopic shape, or the additive is concentrated around macroscopically, and stress is generated, resulting in unevenness of the matrix.

Such a metal pretreatment agent may be a metal salt series containing a component of the same material as the interface of the metal 100 or having a radical group or an oxidizing group of a metal salt series that can be assisted in the acid base substitution reaction, The surface of the metal 100 may be modified by surface modification of the metal 100 by mixing with the metal 100 in a solid state or by mixing with the metal 100 in a solution state.

The reactive polymer 200 introduces chemical reaction energy to lower the reaction energy (reaction enthalpy) of the metal powders 100 to induce a reaction at the crystal expansion interface in the form of grains. The reactive polymer 200 has a carbon chain as a main chain structure, A base polymer 200a capable of introducing a polar group into a chain or a side chain and a modified polymer 200b mixed with the base polymer 200a and having a substituent are graft copolymerized and a polymer preprocessing The surface modification can be performed by the agent. The reactive polymer 200 may be added in an amount of 3 to 30 wt% based on the total weight of the composite material 1. When the reactive polymer 200 is added in an amount of less than 3 wt% The ratio of the composite non-bonding interface to the total non-bonding interface of the composite material (1) can be increased by increasing the strength, The bonding force between the reactive polymer 200 and the metal 100 may be reduced, and the reactive polymer 200 may be injected into the above range. That is, when the reactive polymer (200) is added at a rate higher than the reaction ratio, residual polymer remaining after the interfacial bonding reaction is generated. At this time, the residual polymer acts as a non-uniform stress such as an attractive force between the molecules constituting the matrix in the matrix, stress and the like, and is locally weak because of strength and bonding force, It is possible to reduce the durability of the battery. Furthermore, as the residual polymer increases due to the pores of the polymer itself, there may arise a problem of structural resistance of the pores due to heat conduction and the like of the composite material (1). Therefore, it is preferable that the composite material (1) is poured into the above range to reduce the amount of generated residual polymer to reduce voids.

The base polymer 200a may be a polymer in which a polar group is introduced into the main chain or side chain of the polymer in an organic polymer chain having a carbon chain (= C =, -CH2-) One or more of HDPE (high density polyethylene), LDPE (low density polyethylene), LLDPE (liner-) and EVA (ethylene vinylacetate series) may be selected and used.

The modified polymer 200b may be selected from the group consisting of propylene glycol, propylene glycol methyl ether, peroxide, carboxy acid, acetic anhydride, nitric acid, ammonium nitrate, maleic acid, maleic anhydride, sulfuric acid, sulfur trioxide, acid is mixed with the polymer and extruded to modify it. The mixing ratio of the base polymer 200a and the reforming polymer 200b for preparing the reactive polymer 200 may vary depending on the reaction ratio of the main chain and side chain of the selected base polymer 200a to the base polymer, The modified polymer 200b may be mixed with 0.1 to 20% by weight based on the total amount of the modified polymer 200a. At this time, the substitution reaction rate is increased according to the mixing ratio of the modified polymer 200b and the base polymer 200a, but when the amount of the modified polymer 200b is more than 20 wt%, the base polymer 200a is deteriorated or decomposed The problem arises that the modified polymer 200b can be mixed within the above range.

Considering the compatibility when the main material of the metal 100 is selected, the reactive polymer 200 containing a polar group and a substituent group generated by mixing the base polymer 200a and the modified polymer 200b is mixed with an acrylonitrile (butadiene styrene copolymer), HIPS (high impact polystyrene), GPPS (general polystyrene), PMMA (polymethylmetha acrylic), styrene butadiene styrene copolymer (SBS), butadiene rubber (BR), modified (MBR) , EMPP (Modified polypropylene rubber), EPDM (Ethylene propylene rubber), SEBS (Styrene ethylene butadiene styrene), Polyamide, Polyimide, PTFE, PPE, mPPO, INGAGE, EEA acrylate), TPU, and Alpha-olefin copolymers are selected and subjected to a second low-temperature graft polymerization. By performing the extrusion compounding process twice, compounding at one time can solve the problem that the gel is generated and the efficiency of the reaction activator is substantially reduced due to the degradation of the polymer. During the modification of the reactive polymer 200, 1010, a stearate-based dispersant, Ca / Zn, and the like were charged in an amount of 0.005 to 0.15 PHRS (PHARS: 100) as a primary antioxidant. A metal oxide series may be added.

Meanwhile, the coarse reactive polymer (200) may be powdered to increase the activity of the particle interface until the secondary extrusion process. At this time, the method for pulverizing the reactive polymer 200 may be classified into a chemical method and a mechanical method. In order to prevent the reactive polymer 200 from being affected by the chemical reaction characteristics in the chemical pulverization process, (Physical) milling method. Through such a pulverization process, the average diameter of the reactive polymer 200 may be 50 to 100 占 퐉.

The reactive polymer 200 is divided into two stages and is manufactured. This is because some of the polymers mentioned above have a characteristic of being easily deteriorated to suppress or prevent a process accident such as an explosion or a fire which may occur when the polymer is put in at a time.

The reactive polymer 200 may be surface-modified with a polymer pretreatment agent to facilitate bonding with the metal 100 prior to mixing with the metal 100, as in the case of the metal 100, (For example, a metal salt series in which a combination of a carboxyl group, an alkyl group, an amine group and the like containing an aluminum, zirconium, iron or the like is combined) may be used as the pretreatment agent. More specifically, the polymer pretreatment agent may be a metal salt series in which a radical group belonging to the base polymer of the reactive polymer 200 is shared. When a solid polymer preprocessing agent is used, it is selected that the melting point is lower than the melting point of the reactive polymer 200 Can be used.

Referring to FIG. 2, the interface between the metal 100 and the reactive polymer 200 at which the covalent bond is formed is an interface at which the metal 100 is radical-displaced to the extended reactive interface. That is, the bonding interface S is an excited state from the viewpoint of electron energy in a state in which radicals in the mixed state are activated, and forms a matrix while undergoing a crystallization process during cooling using the composite material (1). Here, a mixing pretreatment agent for increasing the reactivity at the interface between the surface-modified metal (100) and the reactive polymer (200) and preventing phase separation of the metal (100) and the reactive polymer (200) can do. At this time, the liquid pretreatment agent may be a liquid metal salt series, and the liquid metal salt may be a metal salt having a radical group or an oxide group, which can be assisted in the acid-base substitution reaction of the metal 100 and the reactive polymer 200 .

An example of the mechanism by the pretreatment agent used when mixing the metal 100 and the reactive polymer 200 is as follows. When the aluminum 100 is used as the metal 100 and the reactive polymer 200 is olefin-based, When a radical group is contained, Al-O-CH ₃ or Zr-O-CH ₃ can be used as the pre-mixture preparation agent. Here, a covalent bond occurs when the covalent bond reaches the processing temperature of the acid-base substitution reaction of the reactive polymer (200). Therefore, when the metal (100) and the reactive polymer (200) start to be kneaded by reaching a certain temperature in the mixing plant, the pretreatment agent is electrostatically induced so as to form a morphology with a uniform orientation, , So that the substitution reaction can be smoothly performed.

On the other hand, a thermally conductive additive (500) for injecting into the void formed by the metal (100) and the reactive polymer (200) constituting the composite material (1) and increasing the thermal conductivity of the composite material .

The thermally conductive additive 500 is added to compensate the thermal conductivity of the composite material 1 and includes a thermally conductive additive 500a for the polymer and a metal 100 and a reactive polymer 200) may be included in the mixed thermal conductive additive (500b). The thermally conductive additive 500 is added to compensate for the thermal conductivity of the portion of the reactive polymer 200 that generates the interfacial substitution bond (free electron sharing) with the metal 100 through the chemical reaction, in which the morphology is formed. 200) is small, the thermal conductivity of the morphology is in the range of 0.2 to 0.5 kPa / m · h · ° C. Therefore, it is added to increase the thermal conductivity of the reactive polymer (200) filled in the void.

The thermally conductive additive 500a for a polymer is prepared by adding the remaining monomer remaining after the reaction among the voids remaining after bonding and bonding the polymer 100 to the gap between the voids of the reactive polymer 200 itself and the metal 100, The thermoconductive additive 500 may be added to fill the pores due to the 'secondary polymer firing' occurring at the end of the reaction. Here, in the general polymer process, the secondary polymeric carbonation prescribes an antioxidant, an internal / external activator, etc. However, it is preferable that the reactive polymer 200 of the present invention does not allow the reactive polymer 200 to interfere with the bonding. In order to fill the voids presented above, the reactive polymer 200 may be added at the time of its manufacture to allow the thermally conductive additive 500a to be planted in the pores of the reactive polymer 200 itself.

The thermally conductive additive 500b for mixing is added to increase the thermal conductivity of the reactive polymer 200 that is filled in the interface between the respective structures and the pores and in the pores when the metal 100 and the reactive polymer 200 are mixed Which can be inserted between the voids formed by the metal members 100, thereby increasing the thermal conductivity of the overall area of the matrix constituting the composite material 1. [

As the material of the thermally conductive additive 500, a material having a higher conductivity than the reactive polymer 200 may be selected. Further, a material which has not reacted with the reactive polymer 200 and has not been decomposed can be selected. The particle size of the thermally conductive additive 500 may be selected to have a spherical shape having a size that can be filled between the pores of the polymer morphology. This is because, when a material having a spherical shape is selected, the intermolecular stresses of the matrix of the composite material (1) can be uniform or equivalent. The amount of the thermally conductive additive 500 to be added may be up to 55 wt% with respect to the total amount of the reactive polymer 200 to be added. More preferably, when the second metallic material 130 is the final main material and the amount of the reactive polymer 200 is 7%, the thermally conductive additive 500 is added to the extent that the mechanical bonding strength is not hindered up to 30% .

Materials for the thermally conductive additive (500) include gold, silver, copper and copper alloys, aluminum and aluminum alloys, magnesium and magnesium alloys, alloys based on iron and iron oxides or iron, magnesium hydroxide Metal salts such as aluminum, alumina (Al ₂ O ₃ ), beryllia (BeO ₂ ), boron nitride, magnesium whisker, silicon carbide, silicon nitride, aluminum nitride and MgO, graphene, graphite, carbon A high carbon black or a CNT series, Talc, CaCO ₃ , SiO ₂ or a mineral powder containing a metal component may be selected and used. At this time, depending on the kind of the production process using the composite material 1, that is, the process such as extrusion, injection, press, die casting, etc., a petroleum solvent (benzene naphtha solvent), fatty acid oil (olive oil or palm oil) , Mineral oil, silicone oil, peroxydic oil, olefin wax, Di-tetra butyl-peroxide, Zirco-aluminate coupling agent, ethylene glycol, Glycol) is selected and applied onto the surface by using a high-speed mixer or a powder mixer.

The composite material 1 constituted as described above is constituted by interfacial bonding between the metal 100 and the reactive polymer 200 so that a new molecular structure is obtained due to strong bonding between the metal 100 and the reactive polymer 200 It is possible to prevent breakage or trouble even if it is manufactured in various sizes due to the increased strength and bonding force of the metal material 100 and the bonding material of the polymer, The weight of the heat discharging body made of the heat sink 1 can be reduced, and can be applied to a field where a reduced load is used and used.

Hereinafter, a method for manufacturing the above-described composite material 1 will be described. Referring to FIG. 3, a method of manufacturing a heat dissipating metal organic composite material according to an embodiment of the present invention includes the steps of preparing a metal material 100, preparing a reactive polymer material 200, 200) is incorporated to cause a covalent bond or an ionic bond at the interface.

First, the metal 100 is selected as a material that exhibits desired heat dissipation characteristics of the composite material 1 and can achieve desired mechanical properties (S100). In this case, the metal (100) is not different from a metal-based alloy through smelting refining or the like, but it can be combined with a chemical acid-base reaction to occur at a later stage and an activating radical to be shared with a polymer Metal surface modification of the surface, treatment of the metal interface to be bonded, and the like can be selected. That is, the metal 100 may be selected from a single kind of metal powder or a metal having a good reactivity with a radical group among two or more kinds of metal powders, considering the physicochemical properties of the composite material 1 (for example, Hardness, high hardness, high stiffness / thermal conductivity, high hardness / electric conductivity or high stiffness / high hardness / thermal conductivity / electric conductivity) (S110). This is because a single metal powder or two or more kinds of metal powders are selected from among the metal powders 100 described above and the metal powders 100 selected for the chemical reaction (acid base reaction, hydrolysis reaction) A metal can be chosen that easily releases electrons when attacked by activated radicals. The metal 100 thus selected is one of the important parameters constituting the matrix having the morphology.

In addition, the size and shape of the particles of the metal 100 are controlled (S120). That is, to reduce the repulsive force Fr due to the homogeneity of the bond at the interface between atoms or molecules, to increase the crystallization atom or intermolecular attraction force Fc, and to construct the matrix. In order to determine the particle size of the first metal material 110 and the second metal material 130, a gap between the first metal material 110 and the second metal material 130 may be reduced by applying a gap between the metal materials, And particle size can be determined.

After the type, particle size, and shape of the metal (100) are selected, the surface of the metal (100) is modified so that the energy level of the metal atoms of the metal (100) (Preprocessing process) is performed (S130). That is, since the covalent molecular structure formed at the metal (100) interface is not stable or the reactivity is low, the bonding ratio per mole is low, or both molecules are formed by the repulsive force to form pores, A pretreatment process for modifying the surface of the metal 100 may be performed in order to increase the reactivity and maintain the covalent bond with increased bonding force. Referring to FIG. 5, in order to increase the binding force of the metal 100 through the pretreatment process, the reaction force of the radical group, the repulsive force, A stable transition layer can be formed by stably grafting with the radical groups of the side chain of the reactive polymer 200 to be bonded at the interfaces SA and SB as shown in FIG. Thus, the metal salt-based solvent or powder type pretreatment agent used in the pretreatment agent may be selected from the group consisting of a carboxyl group to which aluminum, zirconium, iron, or the like is bound, an alkyl group , An amine group and the like can be used in combination.

Thereafter, a reactive polymer 200 for inducing a chemical reaction for interfacial bonding with the metal 100 is prepared (S200). That is, as described above, a base polymer having a main chain structure of a carbon chain and a modified polymer (200b) having a substituent group are graft-copolymerized (S210), and then finely pulverized and atomized (S220). As in the pretreatment process of the metal 100, a pretreatment process is performed to modify the surface of the reactive polymer 200 to facilitate interfacial bonding with the metal 100 (S230). In the pretreatment process of the reactive polymer 200, a process of capturing radicals by activating a metal group through RO, ROO, ROOH, etc. through a chemical reaction at the interface of the selected metal 100 is performed. In the pretreatment of the reactive polymer 200, when the base polymer 200a is modified with the modified polymer 200b having a terminal polar group, a metal salt / metal powder having high reactivity is added, (200), powdered and then pretreated on the surface immediately before the synthesis with the metal (100). The former has a cost increase aspect that requires a complicated prescription and double grafting process in polymer modification, but the latter is simple, but it is difficult to store for a long time due to bleeding out phenomenon after pretreatment. .

Meanwhile, in the step of preparing the reactive polymer 200, a process of incorporating the thermally conductive additive 500a for the polymer is further performed. That is, as described above, when the reactive polymer 200 is prepared to fill the voids formed by the reactive polymer 200 itself, the thermally conductive additive 500a for the polymer is added to fill the voids of the reactive polymer 200, It is possible to increase the conductivity.

After the metal 100 and the reactive polymer 200 are prepared and mixed, the metal 100 and the reactive polymer 200 are mixed (S300) and subjected to graft polymerization (S400) to complete the manufacture of the composite material 1 (S500). At this time, as described above, the thermally conductive additive for mixing may be further added to the mixture in order to increase the thermal conductivity of the composite material (1). Referring to FIG. 6, there is shown a diagram for explaining the covalent substitution bonding between the reactive polymer 200 and the metal (100) interface. As described above, the pretreated reactive polymer 200 is used as an auxiliary means for increasing the reaction ratio per mole during the chemical covalent bonding reaction of the metal 100, that is, increasing the reactivity. This is because the surface modification by the pretreatment agent of the metal 100 and the reactive polymer 200 and the reaction by the pretreatment at the time of mixing the metal 100 and the reactive polymer 200, So that the reactive polymer 200 can be easily reacted.

As described above, the liquid metal salt used as the mixing pretreatment agent is added to the metal 100 and then mixed. Then, the powder obtained by pulverizing the reactive polymer 200 is mixed, and the mixture is rotated at a high speed so that the metal 100 and the reactive polymer (200) is performed.

Hereinafter, thermal conductivity and other mechanical properties of a molded product manufactured by applying the composite material (1) of the present invention are shown.

The first metallic material 110 of the metal material 100 composing the composite material 1 was selected from aluminum powder 20 m and the second metallic material 130 was selected from aluminum powder 5 m. The reactive polymer 200 is selected from the above-described base polymer 200a and the modified polymer 200b to be modified with the reactive polymer 200 and the thermally conductive additive 500 is added during the second extrusion process of the reactive polymer 200. [ Were graft-polymerized and reformed. Thereafter, before mixing the metal and the reactive polymer (200), the surface of the metal and the reactive polymer (200) were preliminarily treated with a liquid metal salt by a mixer, and the metal and the reactive polymer (200) were dried and mixed at 100 ° C for 1 hour. And pressed and heated in a press to a thickness of 60 mm. Thereafter, the mold was preheated to 250 캜 and heated at the temperature of 300 캜 while being heated for 5 minutes to complete a molded product. At this time, it can be seen that the specific gravity of the finished molded article was 2.05, and the specific heat was reduced to 1.89 ㎈ / g 占 폚. On the other hand, when molding by injection molding, the temperature of the injection die was 300 ° C, the feeding zone was 180 ° C, the mixing region was 250 ° C and the outbot was 280 ° C. When the mixing ratio was the same as that in press molding, And the specific gravity was decreased by 5%.

&Lt; Heat conduction comparative experiment &

Table 1 below shows the results of a comparison of thermal conductivity between a conventional aluminum metal heat sink and a heat sink made of a composite material (1) having the above combination. At this time, each heat sink shows experimental results applied to 40W LED.

Time (min) Conventional Example on 17.7 18.2 2 19.9 21 4 23 24.8 6 24.5 29 8 26.8 33 10 27.8 12 28.2 14 29.1 16 29.8 18 30 20 30.3

Referring to Table 1, the heat sinks of the conventional and the embodiments are equilibrated with the heat radiation from the heat source (40W LED) at a temperature of 30 to 35 ° C. Therefore, it is possible to confirm the heat radiation performance according to the time to reach 30 ° C first. Here, it can be seen that the heat radiating plate made of the composite material (1) of the embodiment reaches 8 minutes at 30 占 폚 where the heat radiating equilibrium, while the conventional heat radiating plate takes 16 minutes. As a result, it can be confirmed that the heat sink made of the composite material (1) of the present invention exhibits increased thermal conductivity even when the specific gravity is reduced due to the polymer included in the conventional heat sink. This is realized by the fact that the reactive polymer 200 induces strong interfacial bonding by lowering the reaction enthalpy of the metal 100, thereby increasing the heat transfer characteristic by strong bonding between the composite materials 1.

Hereinafter, the measurement of the thermal conductivity of the composite material (1) and the numerical results of the thermal conductivity of the composite material (1) using the same will be described.

As described above, the thermal conductivity of the composite material 1 may be changed depending on the size of the metal 100, depending on whether the reactive polymer 200 is modified or not, depending on the weight ratio of the reactive polymer 200. [ This is because the mechanism for constituting the composite material 1 forms a covalent bond by the metal organic substitution at the interface, and the three types of heat transfer (convection, radiation, movement of free electrons) This is caused by heat transfer by electrons.

[Formula 1]

Fourier equation (heat transfer structure correlation by free electrons)

Therefore, it can be deduced that the difference in heat transfer at each interface as shown in the following equation resists conduction like electric resistance.

In addition, the following relation can be obtained in an electric circuit connected in series from the electric theory.

Here, the heat flow and the electric flow are similar, and the corresponding amounts are as follows.

,

or

Therefore, the heat transfer resistance in the conductor becomes such a form of the equation, and the thermal conductivity k can be summarized as follows. At this time, since the method of the experiment proceeds in the form of a plate, ki is expressed by Equation 2 below. At this time, each parameter can be measured by a horizontal thermal conductivity meter.

[Formula 2]

L: Distance between two temperature sensors

ρ: Density of the specimen

T1, T2: Temperature of sensor point

C: Specific heat

Δt: Heat transfer time difference

In the following, measurement results of comparative properties for the composite material (1) (Examples 1 to 5) of the present invention by the above-mentioned method of measuring the flatness thermal conductivity are shown.

(Example 1)

First metal: 70 wt% of spherical particles of 200 탆 of aluminum, spherical particle weight ratio of 23 wt% of second metal: aluminum 20 탆, 30 pts of thermally conductive additive at the second modification with reactive polymer Modified by adding: 7wt%, zirconia aluminum liquid salt mentioned as surface pretreatment agent of metal and reactive polymer at the time of mixing 0.005Phrs. Mixed with a thermally conductive additive in a ratio of 7: 3 (working: hot press)

(Example 2)

First metal: spherical particles of 200 탆 aluminum of 65 wt%, spherical particles of second metal: aluminum of 20 탆, weight ratio of 23 wt%, modified by addition of 30 Phrs. Of thermally conductive additive at the time of secondary modification with reactive polymer, 12wt%, zirconia aluminum liquid phase salt referred to as surface pretreatment agent of metal and reactive polymer at mixing 0.005Phrs. Mixed with a thermally conductive additive in a ratio of 7: 3 (working: hot press)

(Example 3)

A second metal: one of the above-mentioned materials, with a spherical particle weight ratio of 5 占 퐉 being 5 wt%; a thermally conductive additive 30 Phrs : 5 wt% of the zirconia aluminum liquid salt mentioned as the surface pretreatment agent of the metal and the reactive polymer at the time of mixing 0.005Phrs. Mixed with a thermally conductive additive in a ratio of 7: 3 (working: hot press)

(Example 4)

A second metal: one of the above-mentioned materials was selected, but a spherical particle weight ratio of 5 탆 was selected to be 5 wt%, and a thermally conductive additive 30 Phrs The modified zirconia aluminum liquid salt referred to as the surface pretreatment agent of the metal and the reactive polymer at the time of mixing 0.005Phrs. Mixed with a thermally conductive additive in a ratio of 7: 3 (working: hot press)

The results of varying the respective thermal conductivities according to the conductivity characteristics in interfacial bonding and the amount of the reactive polymer 200 in which the sizes of the material particles according to the conditions of Examples 1 to 4 are different are shown in Table 2 .

division
Data (unit) Example 1
Example 2
Example 3
Example 4
ρ (g / cm 3) 1.936271 1.932747 1.905985 1.745426 L (cm) 9 9 9 9 c (㎈ / g ° C) 0.23 0.244 0.251 0.227 d time (sec) 20 20 10 10 T1 (° C) 68 58 69.2 68 T2 (占 폚) 27 24 24.4 23.1 ln [T1 / T2] 0.923671 0.882389 1.042418 1.079675 Ki (W / mK) 97.6342 108.226 185.869 148.624

As a result, the conductivity and the thermal conductivity value of the reactive polymer (200) vary depending on the interfacial bonding between the materials, and the resultant interface and residual polymer and voids during the interfacial bonding reaction are the heat transfer resistance As shown in Fig. However, it can be seen that the thermal conductivity rapidly increases when the size of the metal is nanoparticles or submicron fine particles.

(Example 5)

(Round bar) was added to the raw material of Example 3 manufactured under the above-described conditions, and the heat transfer characteristics were measured in the same manner as in Examples 1 to 4 described above.

division
Data (unit) Example 5 ρ (g / cm 3) 2 L (cm) 9 c (㎈ / g ° C) 0.251 d time (sec) 10 T1 (° C) 69.2 T2 (占 폚) 30.8 ln [T1 / T2] 0.809486 Ki (W / mK) 239.353

In Example 5, it can be seen that the overall conduction amount up to T2 increased greatly with the increase of the initial heat transfer rate by using the booster, compared to the thermal conductivity of Example 3. [

The following Table 4 shows the comparison of the physical properties of the material used as the conventional heat sink material and the physical properties of the composite material (1) of the present invention.

Thermal conductivity (W / mK) importance Tensile (kg / cm2) Elongation (%) aluminum 220 2.69 750 25 Aluminum alloy 147 2.75 950 2 Copper 388 8.9 1400 50 Example 1 90-100 1.93 350 2.3 Example 2 200 ~ 110 1.93 430 4 Example 3 180-190 1.9 430 4 Example 4 140-150 1.75 550 5 Example 5 230 ~ 240 2.05 430 4

As a result, it can be seen that the composite material (1) of the present invention has a lower specific gravity than that of conventional heat dissipating materials, and exhibits heat conduction equal to or similar to that of a conventional heat dissipating material. Since the composite material of the present invention includes the reactive polymer 200, the conventional heat dissipation material made of metal has a relatively high thermal conductivity in the external environment It is possible to solve the reduction of the heat radiating effect due to the phenomenon that the heat is changed and exposed. That is, since the reactive polymer 200 surrounds the surface of the metal 100 with an average thickness of 10 nm, the heat dissipator made of the composite material 1 of the present invention may have increased chemical resistance, flame resistance, and weather resistance.

As described above, the composite material (1) of the present invention shows a form in which the conductive polymer surrounds the surface of the metal, thereby increasing the chemical resistance, salt resistance and weather resistance. In addition, since the main chain of the reactive polymer 200 is made of carbon, the hydrogen attached to the side chain of the carbon chain on the surface of the metal mold during the injection or hot press molding of the composite material 1 is decomposed, So that a fine coating film can be formed without a separate thermal conductive paint. Therefore, even when the thickness of the polymer in a metallic form is 10 to 50 nm, excellent chemical resistance and salt resistance effect can be obtained by stably depositing the polymer as described above. 7 and 8 manufactured through such a composite material 1 can obtain a heat radiator with a reduced specific gravity and an increased heat dissipation performance. As seen from the edge face of the specimen, It can be confirmed that a dense surface in which cracks did not occur even in the case of mixing.

Although the present invention has been described with reference to the accompanying drawings and the preferred embodiments described above, the present invention is not limited thereto but is limited by the following claims. Accordingly, those skilled in the art will appreciate that various modifications and changes may be made thereto without departing from the spirit of the following claims.

100: metal 110: first metal
130: Second metal 200: Reactive polymer
200a: base polymer 200b: modified polymer
250: Residual polymer 300: Pretreatment agent
500a, 500b: thermally conductive additive 1: composite matrix

Claims

Wherein the metal and the reactive polymer are intermixed with each other and the interface between the mixed metal and the reactive polymer has a structure in which the metal and the reactive polymer molecules are mutually covalently bonded or ionically bonded.

The method according to claim 1,
Wherein the metal is surface-modified with a metal pretreatment agent so that an energy level between metal atoms is reduced.

The method of claim 2,
Wherein the metal comprises a first metal and a second metal having different average diameters of the atomized particles, and the average diameter (r ₁ ) of the first metal is greater than the average diameter (r ₂ ) of the second metal. .

The method of claim 3,
Wherein the first metal has an average diameter (r ₁ ) of 50 nm to 50 탆.

5. The method according to any one of claims 1 to 4,
The metal may be one or more of an aluminum or aluminum alloy (an alloy of iron, silicon carbide, manganese, magnesium or the like with an aluminum weight ratio of 70% or more), a copper or copper alloy series, a magnesium or magnesium alloy series, Or use it,
Alumina (Al ₂ O _3), iron oxide (Iron oxide), a mineral powder containing the metal element (Na, Al, Si ₂ O _6), aluminum silicate (mica, mica seats), aluminum hydroxide (Al (OH) ₃₎ , of the magnesium hydroxide (Mg (OH) _2), calcium carbonate (CaCO _3), barium sulfate, magnesium oxide _{(MgO), Mg3 (Si 4} O 10) a ceramic or a metal salt containing a metal component comprising a (OH) ₂ Composite materials that use one or more of them.

5. The method according to any one of claims 1 to 4,
The reactive polymer
A base polymer having a carbon chain as a main chain structure and capable of introducing a polar group into the main chain or side chain, and a modified polymer having a substituent group are graft-
Wherein the surface of the composite material is modified by a polymer pretreatment agent so as to promote interfacial bonding with the metal.

The method of claim 6,
Wherein the reactive polymer further comprises a thermally conductive additive for the polymer.

The method of claim 6,
Wherein the reactive polymer is added in an amount of 3 to 30 wt% based on the total weight of the composite material.

The method of claim 8,
Wherein the modified polymer comprises 0.1 to 20 wt% based on the total amount of the base polymer.

The method according to any one of claims 1 to 4,
The structure in which the molecules of the metal and the molecules of the reactive polymer are mutually covalently bonded or ion-bonded is increased by the mixing pretreatment agent for increasing the reactivity at the interface between the metal and the reactive polymer, Wherein the composite material is accelerated.

The method of claim 6,
The structure in which the molecules of the metal and the molecules of the reactive polymer are mutually covalently bonded or ion-bonded is increased by the mixing pretreatment agent for increasing the reactivity at the interface between the metal and the reactive polymer, Wherein the composite material is accelerated.

The method of claim 7,
And a thermally conductive additive for mixing in a gap between the metal materials.

The method of claim 12,
Wherein the thermally conductive additive for mixing is fed to a content of 55 wt% or less based on the total amount of the reactive polymer.

14. The method of claim 13,
The thermally conductive additive may be selected from the group consisting of gold, silver, copper and copper alloys, aluminum and aluminum alloy series, magnesium and magnesium alloys, iron and iron oxide or iron based alloys, magnesium hydroxide or aluminum hydroxide containing metals, Metal oxides, graphene, graphite, carbon fine powder or CNT based metals such as Al ₂ O ₃ , BeO ₂ , boron nitride, magnesium whisker, silicon carbide, silicon nitride, aluminum nitride, Composite materials that use one or more of mineral components including components.

15. The method of claim 14,
Wherein the surface of the thermally conductive additive is coated with one or more selected from petroleum solvent, fatty acid oil, white oil, mineral oil, silicone oil, olefin wax, DTBT and glycol.

A method of manufacturing a heat dissipating metal organic composite material,
Preparing a metal;
Preparing a reactive polymer; And
And mixing the metal and the reactive polymer to form a covalent bond or an ionic bond at the interface.

18. The method of claim 16,
The step of incorporating the metal-
A mixing pretreatment step of increasing the reactivity of the interface between the metal molecules and the molecules of the reactive polymer to be mutually covalently bonded or ionically bound to prevent phase separation and thereby inducing uniform mixing, &Lt; / RTI >

The method according to claim 16 or 17,
The step of manufacturing the metal may include:
A process of selecting and atomizing a single metal or two or more metals; And
And a surface modification step of modifying the surface of the selected metal so that energy levels of metal atoms of the selected metal are reduced.

The method according to claim 16 or 17,
Wherein the step of preparing the reactive polymer comprises:
Graft-copolymerizing a base polymer having a high molecular weight and a modified polymer having a substituent;
A step of atomizing the copolymerized polymer; And
And a step of modifying the atomized polymer with a polymer pretreatment agent to promote interfacial bonding with the metal.

The method of claim 19,
Wherein the step of preparing the reactive polymer further comprises the step of incorporating a thermally conductive additive for the polymer.

The method of claim 20,
Wherein the metal-reactive polymer incorporation step further comprises incorporating a thermally conductive additive for mixing.