CN106753263B - Heat-conducting phase-change material and preparation method thereof - Google Patents
Heat-conducting phase-change material and preparation method thereof Download PDFInfo
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- CN106753263B CN106753263B CN201611232229.3A CN201611232229A CN106753263B CN 106753263 B CN106753263 B CN 106753263B CN 201611232229 A CN201611232229 A CN 201611232229A CN 106753263 B CN106753263 B CN 106753263B
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- C09K5/02—Materials undergoing a change of physical state when used
- C09K5/06—Materials undergoing a change of physical state when used the change of state being from liquid to solid or vice versa
- C09K5/063—Materials absorbing or liberating heat during crystallisation; Heat storage materials
Abstract
The invention provides a heat-conducting phase-change material which contains a resin matrix, a heat-conducting filler and a coupling agent, wherein the resin matrix is at least one of hydrogenated modified wax powder, pinene resin modified wax and pentaerythritol ester modified wax. The invention also provides a preparation method of the heat-conducting phase-change material. The heat-conducting phase-change material has high heat conductivity.
Description
Technical Field
The invention relates to the technical field of thermal interface materials, in particular to a heat-conducting phase-change material and a preparation method thereof.
Background
Phase Change Materials (PCM) include inorganic Phase Change materials, organic Phase Change materials, and composite Phase Change materials. The phase-change material with the phase-change temperature of 20-80 ℃ has wide application in heat absorption and heat storage, but most of the existing PCM with the phase-change temperature range has high cost and poor heat conduction performance, and is not beneficial to popularization and application.
Disclosure of Invention
The invention mainly aims to provide a heat-conducting phase-change material, and aims to provide a heat-conducting phase-change material with high heat conductivity.
In order to achieve the purpose, the invention provides a heat-conducting phase-change material which contains a resin matrix, a heat-conducting filler and a coupling agent, wherein the resin matrix is at least one of hydrogenated modified wax powder, pinene resin modified wax and pentaerythritol ester modified wax.
Preferably, the heat-conducting phase change material comprises the following components in parts by weight: 5.5 to 17.5 parts of resin matrix, 57.5 to 70.7 parts of heat-conducting filler and 0.3 to 1.5 parts of coupling agent.
Preferably, the heat conductive filler is at least one of boron nitride, alumina powder, aluminum nitride, zinc oxide, silicon carbide, silver powder, aluminum powder, copper powder, silver-coated aluminum powder, silver-coated copper powder, and alumina-coated silver powder.
Preferably, the coupling agent is at least one of trimethyl aluminate, triisopropyl aluminate, tribenzyl chlorate and isobutyl triethoxy silicon.
Preferably, the heat-conducting phase change material further comprises 0-0.3 parts by weight of an anti-aging agent, wherein the anti-aging agent is at least one of 2, 8-di-tert-butyl-4-methylphenol, butyl hydroxyanisole, tert-butyl hydroquinone and dibutyl hydroxytoluene.
Preferably, the heat-conducting phase-change material further comprises 8-12 parts by weight of a reinforcing agent, and the reinforcing agent is at least one of active whisker silicon, fumed silica and nano calcium carbonate.
Preferably, the heat-conducting phase change material further comprises 14-18 parts by weight of a tackifier and/or 1.5-6.0 parts by weight of a flame retardant, wherein the tackifier is at least one of bismaleimide modified nitrile rubber, epoxy modified nitrile rubber, hydrogenated modified nitrile rubber and rosin modified nitrile rubber, and the flame retardant is at least one of aluminum hydroxide powder, melamine phosphate and polyphosphate.
Preferably, the heat-conducting phase-change material is a coiled material with the thickness of 0.1-0.5 mm and the width of 15-240 mm.
The invention also provides a preparation method of the heat-conducting phase-change material, which comprises the following steps:
adding matrix resin, a coupling agent and a heat-conducting filler into a stirring kettle, heating to melt the matrix resin, and stirring to obtain a mixture, wherein the resin matrix is at least one of hydrogenated modified wax powder, pinene resin modified wax and pentaerythritol ester modified wax;
vacuumizing the stirring kettle to obtain molten fluid;
and carrying out molding treatment on the molten fluid to obtain the heat-conducting phase-change material.
Preferably, the step of adding the matrix resin, the coupling agent and the heat-conducting filler into the stirring kettle further comprises adding at least one of an anti-aging agent, a reinforcing agent, a tackifier and a flame retardant into the stirring kettle.
Compared with the prior art, the invention has the following beneficial effects: the hydrogenated modified wax powder, the pinene resin modified wax and the pentaerythritol ester modified wax selected by the technical scheme have high heat storage density and good thermochemical stability, the melting point is 50-75 ℃, the temperature is consistent with the working temperature of an electronic element, and the heat-conducting phase-change material is subjected to solid-liquid transition in the temperature range to absorb a large amount of heat, so that the temperature of the electronic element is reduced; the heat-conducting filler is dispersed in the resin matrix to form a heat-conducting network chain, so that the heat-conducting property of the resin matrix is greatly improved; the coupling agent is used for improving the interface compatibility of the heat-conducting filler and the resin matrix and reducing the thermal resistance between the heat-conducting filler and the resin matrix interface.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.
The invention provides a heat-conducting phase-change material which contains a resin matrix, a heat-conducting filler and a coupling agent, wherein the resin matrix is at least one of hydrogenated modified wax powder, pinene resin modified wax and pentaerythritol ester modified wax.
The heat-conducting phase-change material is filled in a gap between the electronic element and the heat-radiating substrate, and heat generated by the electronic element is conducted to the heat-radiating substrate and then conducted to the surrounding environment.
The hydrogenated modified wax powder, the pinene resin modified wax and the pentaerythritol ester modified wax selected by the technical scheme have high heat storage density and good thermochemical stability, the melting point is 50-75 ℃, the temperature is consistent with the working temperature of an electronic element, and the heat-conducting phase-change material is subjected to solid-liquid transition in the temperature range to absorb a large amount of heat, so that the temperature of the electronic element is reduced; the heat-conducting filler is dispersed in the resin matrix to form a heat-conducting network chain, so that the heat-conducting property of the resin matrix is greatly improved; the coupling agent is used for improving the interface compatibility of the heat-conducting filler and the resin matrix and reducing the thermal resistance between the heat-conducting filler and the resin matrix interface.
The heat-conducting phase-change material comprises the following components in parts by weight: 5.5 to 17.5 parts of resin matrix, 57.5 to 70.7 parts of heat-conducting filler and 0.3 to 1.5 parts of coupling agent.
According to the technical scheme, the resin matrix, the heat-conducting filler, the coupling agent and the anti-aging agent are mixed according to a certain proportion, and the comprehensive performance of the prepared heat-conducting phase-change material reaches the best.
The heat-conducting filler is at least one of boron nitride, alumina powder, aluminum nitride, zinc oxide, silicon carbide, silver powder, aluminum powder, copper powder, silver-coated aluminum powder, silver-coated copper powder and alumina-coated silver powder.
Preferably, the particle size of the heat-conducting filler is 0.1-70 μm.
The heat-conducting filler in the technical scheme of the invention can be selected from ceramics, such as boron nitride, aluminum nitride and silicon carbide, and has higher heat conductivity coefficient due to the special crystal structure; metal oxides such as aluminum oxide and zinc oxide have high cost performance; metal powders, such as silver powder, aluminum powder, copper powder, silver-coated aluminum powder, silver-coated copper powder, and aluminum oxide-coated silver powder, are capable of conducting energy and thus heat by collision of free electrons in the metal. The addition of the heat-conducting filler effectively increases the specific surface area of the heat-conducting phase-change material, remarkably improves the absorption rate of the initial temperature of the hot end and the heat conductivity of the heat-conducting phase-change material, and has the effects of quickly absorbing and transferring heat.
The coupling agent is at least one of trimethyl aluminate, triisopropyl aluminate, tribenzyl chlorate and isobutyl triethoxy silicon.
The coupling agent of the technical scheme of the invention forms a bridge bond between the heat-conducting filler and the resin matrix, and effectively improves the compatibility of the heat-conducting filler as an inorganic substance and the resin matrix as an organic substance, thereby reducing the thermal contact resistance of the heat-conducting filler and the resin matrix and improving the heat-conducting property of the heat-conducting phase-change material.
The heat-conducting phase change material further comprises 0-0.3 part by weight of an anti-aging agent, wherein the anti-aging agent is at least one of 2, 8-di-tert-butyl-4-methylphenol, butyl hydroxy anisole, tert-butyl hydroquinone and dibutyl hydroxy toluene.
According to the technical scheme, the 2, 8-di-tert-butyl-4-methylphenol, the butyl hydroxy anisole, the tert-butyl hydroquinone and the dibutyl hydroxy toluene can prevent the heat-conducting phase-change material from being oxidized, are used for slowing down the aging process of the heat-conducting phase-change material in a high-temperature working environment, and prolong the service life of the heat-conducting phase-change material.
The heat-conducting phase-change material further comprises 8-12 parts by weight of a reinforcing agent, and the reinforcing agent is at least one of active whisker silicon, fumed silica and nano calcium carbonate.
The heat-conducting phase-change material in the technical scheme of the invention is converted into liquid after phase change, and the active crystal whisker silicon, the fumed silica and the nano calcium carbonate are used as reinforcing agents, so that the strength of the heat-conducting phase-change material after liquefaction can be enhanced.
The heat-conducting phase change material further comprises 14-18 parts by weight of a tackifier and/or 1.5-6.0 parts by weight of a flame retardant, wherein the tackifier is at least one of bismaleimide modified nitrile rubber, epoxy modified nitrile rubber, hydrogenated modified nitrile rubber and rosin modified nitrile rubber, and the flame retardant is at least one of aluminum hydroxide powder, melamine phosphate and polyphosphate.
According to the technical scheme, the bismaleimide modified nitrile rubber, the epoxy modified nitrile rubber, the hydrogenated modified nitrile rubber and the rosin modified nitrile rubber are used as the tackifier, so that the effects of preventing sedimentation and thickening can be achieved, and the heat-conducting filler is prevented from aggregating and settling after the heat-conducting phase change material absorbs heat and is liquefied. The flame retardant is added, so that the flame retardant performance of the heat-conducting phase-change material is effectively improved, and the safety is enhanced.
The heat conduction phase change material is a coiled material with the thickness of 0.1-0.5 mm and the width of 15-240 mm.
The heat-conducting phase-change material in the technical scheme of the invention is a coiled material prepared by calendaring and forming, has small thickness, can be filled in a gap between an electronic element and a radiator, and can be cut into different shapes and sizes according to actual requirements.
The invention also provides a preparation method of the heat-conducting phase-change material, which comprises the following steps:
adding matrix resin, a coupling agent and a heat-conducting filler into a stirring kettle, heating to melt the matrix resin, and stirring to obtain a mixture, wherein the resin matrix is at least one of hydrogenated modified wax powder, pinene resin modified wax and pentaerythritol ester modified wax;
vacuumizing the stirring kettle to obtain molten fluid;
and carrying out molding treatment on the molten fluid to obtain the heat-conducting phase-change material.
Preferably, the molten fluid is cooled to 80-120 ℃ and then subjected to calendering treatment.
According to the technical scheme, the matrix resin, the coupling agent and the heat-conducting filler are heated to 100-150 ℃, so that the matrix resin is melted and stirred simultaneously, and the heat-conducting filler and the coupling agent are conveniently and uniformly dispersed in the matrix resin; and then, reducing the temperature of the mixture to 80-120 ℃, so as to facilitate subsequent forming treatment.
The step of adding the matrix resin, the coupling agent and the heat-conducting filler into the stirring kettle further comprises the step of adding at least one of an anti-aging agent, a reinforcing agent, a tackifier and a flame retardant into the stirring kettle.
According to the technical scheme, the anti-aging agent, the reinforcing agent, the tackifier and the flame retardant are added into the heat-conducting phase-change material, so that the anti-aging performance and the physical strength of the heat-conducting phase-change material can be improved, and the heat-conducting filler is prevented from settling and the flame retardant performance is prevented.
The first embodiment is as follows:
weighing 37.5g of hydrogenated modified wax powder, 50g of active whisker silicon, 80g of bismaleimide modified nitrile rubber and 1.5g of 2, 8-di-tert-butyl-4-methylphenol in a stirring kettle, heating and stirring for 120 minutes at the rotating speed of 55-65 rpm and the temperature of 150 ℃;
adding 7.5g of trimethyl aluminate into a stirring kettle, and stirring for 30 minutes at the rotating speed of 35-40 rpm;
adding 9g of melamine phosphate into a stirring kettle, and stirring for 30min at the rotating speed of 20-30 rpm;
adding 314.5g of silver-coated aluminum powder into a stirring kettle, and stirring for 10min at the rotating speed of 18-25 rpm;
scraping the wall, stirring for 120min, vacuumizing and removing bubbles;
cooling the materials to 120 ℃, stirring, vacuumizing, and keeping for 30min to obtain a molten fluid;
and (3) calendering and molding the molten fluid to obtain a coiled material with the thickness of 0.2mm and the width of 240mm, and cooling to obtain the heat-conducting phase-change material.
Example two:
weighing 27.5g of pinene resin modified wax, 60g of active whisker silicon, 70g of rosin modified nitrile rubber and 0.5g of tert-butyl hydroquinone in a stirring kettle, heating and stirring for 120 minutes at the rotating speed of 55-65 rpm and the temperature of 100 ℃;
adding 2.5g of tribenzyl chlorate into a stirring kettle, and stirring for 30 minutes at the rotating speed of 35-40 rpm;
adding 7.5g of aluminum hydroxide powder into a stirring kettle, and stirring for 30min at the rotating speed of 20-30 rpm; adding 332g of silver-coated copper powder into a stirring kettle, and stirring for 10min at the rotating speed of 18-25 rpm; scraping the wall, stirring for 120min, vacuumizing and removing bubbles;
cooling the materials to 80 ℃, stirring, vacuumizing, and keeping for 30min to obtain a molten fluid;
and (3) carrying out calendaring molding on the molten fluid to obtain a coiled material with the thickness of 0.5mm and the width of 120mm, and cooling to obtain the heat-conducting phase-change material.
Example three:
weighing 30g of pentaerythritol ester modified wax, 40g of active crystal whisker silicon, 90g of epoxy modified nitrile rubber and 1.0g of butyl hydroxy anisole in a stirring kettle, heating and stirring for 120 minutes at the rotating speed of 55-65 rpm and the temperature of 120 ℃;
adding 5g of triisopropyl aluminate into a stirring kettle, and stirring for 30 minutes at the rotating speed of 35-40 rpm;
adding 15g of polyphosphate into a stirring kettle, and stirring for 30min at the rotating speed of 20-30 rpm;
adding 319g of alumina-coated silver powder into a stirring kettle, and stirring for 10min at the rotating speed of 18-25 rpm;
scraping the wall, stirring for 120min, vacuumizing to remove bubbles, cooling the material to 100 ℃, stirring, vacuumizing, and continuing for 30min to obtain a molten fluid;
and (3) calendering and molding the molten fluid to obtain a coiled material with the thickness of 0.1mm and the width of 15mm, and cooling to obtain the heat-conducting phase-change material.
The above-mentioned heat-conducting phase-change material is tested for reliability, and the results of the above-mentioned examples are shown in table 1 below by comparing the change of each property.
TABLE 1 thermally conductive phase change materials test results
The aging experiment result shows that the thermal resistance of the heat-conducting phase-change material is almost not changed before and after aging, and the product has good stability.
The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by the present specification, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.
Claims (2)
1. A heat-conducting phase-change material is characterized by comprising the following components in parts by weight: 5.5-17.5 parts of a resin matrix, 57.5-70.7 parts of a heat-conducting filler and 0.3-1.5 parts of a coupling agent, wherein the resin matrix is at least one of hydrogenated modified wax powder, pinene resin modified wax and pentaerythritol ester modified wax, and the heat-conducting filler is dispersed in the resin matrix to form a heat-conducting network; the heat-conducting phase change material also comprises 0-0.3 part by weight of an anti-aging agent, wherein the anti-aging agent is at least one of 2, 8-di-tert-butyl-4-methylphenol, butyl hydroxy anisole, tert-butyl hydroquinone and dibutyl hydroxy toluene;
the heat-conducting filler is at least one of silver powder, aluminum powder, copper powder, silver-coated aluminum powder, silver-coated copper powder and aluminum oxide-coated silver powder;
the coupling agent is at least one of trimethyl aluminate, triisopropyl aluminate, tribenzyl chlorate and isobutyl triethoxy silicon;
the heat-conducting phase-change material also comprises 8-12 parts by weight of a reinforcing agent, wherein the reinforcing agent is at least one of active whisker silicon, fumed silica and nano calcium carbonate;
the heat-conducting phase change material further comprises 14-18 parts by weight of a tackifier and/or 1.5-6.0 parts by weight of a flame retardant, wherein the tackifier is at least one of bismaleimide modified nitrile rubber, epoxy modified nitrile rubber, hydrogenated modified nitrile rubber and rosin modified nitrile rubber, and the flame retardant is at least one of aluminum hydroxide powder, melamine phosphate and polyphosphate.
2. The heat-conducting phase-change material as claimed in claim 1, wherein the heat-conducting phase-change material is a coil with a thickness of 0.1-0.5 mm and a width of 15-240 mm.
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| CN108003406A (en) * | 2017-12-20 | 2018-05-08 | 深圳德邦界面材料有限公司 | A kind of heatproof heat conduction phase-change material and preparation method thereof |
| CN108102376A (en) * | 2017-12-20 | 2018-06-01 | 深圳德邦界面材料有限公司 | A kind of removable heat conduction phase-change material and preparation method thereof |
| CN109679198B (en) * | 2018-12-28 | 2022-03-08 | 苏州赛伍应用技术股份有限公司 | Heat-conducting phase-change material and preparation method thereof |
| CN111073612A (en) * | 2019-12-31 | 2020-04-28 | 深圳德邦界面材料有限公司 | Resin-free low-permeability oil heat conduction mud and preparation method thereof |
| CN114836175A (en) * | 2022-04-13 | 2022-08-02 | 航天特种材料及工艺技术研究所 | Phase change composite material and preparation method thereof |
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| CN103965529A (en) * | 2014-05-07 | 2014-08-06 | 深圳市安品有机硅材料有限公司 | Phase-change heat conductive composition, phase-change heat conductive film and preparation method of phase-change heat conductive film |
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| CN103965529A (en) * | 2014-05-07 | 2014-08-06 | 深圳市安品有机硅材料有限公司 | Phase-change heat conductive composition, phase-change heat conductive film and preparation method of phase-change heat conductive film |
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