CN-117681508-B - Flexible thermal interface material and preparation method and application thereof

CN117681508BCN 117681508 BCN117681508 BCN 117681508BCN-117681508-B

Abstract

The invention discloses a flexible thermal interface material, a preparation method and application thereof, wherein the flexible thermal interface material comprises a first metal layer, a composite material layer and a second metal layer which are sequentially stacked, the composite material layer comprises a metal nano array, a graphene material and a polymer, the metal nano array is formed by a metal nano column array, the graphene material is distributed in the metal nano array, a three-dimensional network structure is formed between the graphene material and the metal nano array, pores are formed in the three-dimensional network structure, and the polymer is filled in the pores. The thermal interface material is prepared by compounding the metal nano array, the graphene material and the polymer, has excellent performances of high thermal conductivity, high flexibility, thermal cycle reliability, oxidation resistance, corrosion resistance and the like, can be widely applied to flat or curved surfaces in electronic devices, radiators or mechanical devices, establishes a high-efficiency heat transfer channel, and realizes a good heat conduction effect.

Inventors

LV SONG
FENG MENGQI

Assignees

武汉理工大学

Dates

Publication Date: 20260512
Application Date: 20231122

Claims (10)

1. A flexible thermal interface material is characterized by comprising a first metal layer, a composite material layer and a second metal layer which are sequentially laminated, wherein the composite material layer comprises a metal nano array, a graphene material and a polymer, the metal nano array is formed by a metal nano column array, the graphene material is distributed in the metal nano array, a three-dimensional network structure is formed between the graphene material and the metal nano array, and pores are formed in the three-dimensional network structure; the graphene materials are sheet materials and are connected with each other in the transverse direction; The graphene material grows on the surface of the metal nano column array, and the graphene material coats the metal nano column array to form a protective layer and connects adjacent metal nano column materials; The polymer is at least one selected from polydimethylsiloxane and polymethyl methacrylate.
2. The flexible thermal interface material of claim 1, wherein one end of the metal nano-pillars is connected to a first metal layer and the other end of the metal nano-pillars is connected to a second metal layer.
3. A flexible thermal interface material as defined in claim 1, wherein the first and second metal layers have a thickness of 100nm to 10 μm, and/or the metal nanopillars have a diameter of 30 to 1000nm, and/or the composite layer has a thickness of 10 to 800 μm.
4. The flexible thermal interface material of claim 1, wherein the first metal layer, the second metal layer, and the metal nano-array are all the same metal material.
5. The flexible thermal interface material of claim 1, wherein the metallic material is at least one of gold, silver, copper, aluminum, nickel, tin.
6. The flexible thermal interface material of claim 1, wherein the metal nanopillars are at an angle of 80-90 ° to the first/second metal layers.
7. A flexible thermal interface material as defined in claim 1, wherein the thermal interface material comprises a tie layer on the first metal layer and/or the second metal layer.
8. The method for preparing the flexible thermal interface material according to any one of claims 1 to 7, which is characterized by comprising the following steps: s1, preparing a metal nano array on a second metal layer, depositing a graphene material in the metal nano array, and filling a polymer to obtain a composite material layer; and S2, electroplating a first metal layer on the composite material layer to obtain the flexible thermal interface material.
9. The method for preparing the flexible thermal interface material according to claim 8, wherein the step of depositing the graphene material in the metal nano-array is characterized in that methane and argon are used as reaction gases, and the graphene material is deposited in the metal nano-array under the conditions that the temperature is 480-520 ℃, the total pressure is 0.8-1 Torr, and the methane partial pressure is 40-50 mTorr, and the radio frequency power is 55-70W.
10. Use of the flexible thermal interface material of any one of claims 1-7 in electronic components, heat sinks or mechanical devices.

Description

Flexible thermal interface material and preparation method and application thereof Technical Field The invention belongs to the field of materials, and particularly relates to a flexible thermal interface material, and a preparation method and application thereof. Background The thermal interface material (THERMAL INTERFACE MATERIAL, TIM) is also called a heat conduction interface material, and can fill the gap between the working device and the heat dissipation device, reduce the contact thermal resistance and improve the heat dissipation performance. An ideal TIM should have a low Bond Line Thickness (BLT), have high thermal conductivity to minimize thermal resistance, and should have good mechanical properties such as high flexibility and compliance to accommodate flexible curved surfaces, and be able to withstand thermal stresses resulting from the difference in thermal expansion between the two connecting materials. However, conventional TIMs, such as solders, greases, gels, and epoxies, do not meet the critical requirements for both high thermal conductivity and good mechanical properties. The polymer-based TIM has high flexibility, but low heat conductivity, and high heat conductivity additives such as metal nano particles, graphite and the like are often required to be embedded in a polymer matrix. However, the interface thermal resistance between the additive and the polymer is high, and the heat conduction performance still cannot meet the current heat transfer requirements of electronic components and mechanical devices. The metal-based TIM has an order of magnitude higher thermal conductivity than the polymer-based TIM and excellent heat transfer properties, but it has the disadvantages of high melting point, high soldering temperature, and very poor mechanical compliance, and cannot accommodate the curved surfaces of flexible devices. Therefore, none of the existing thermal interface materials can meet the requirements of increasingly developed electronic components and mechanical devices for high thermal conductivity and flexible thermal interface materials. Disclosure of Invention In order to overcome the problems of the prior art, it is an object of the present invention to provide a flexible thermal interface material. The second purpose of the invention is to provide a preparation method of the flexible thermal interface material. It is a further object of the present invention to provide a flexible thermal interface material for use in an electronic component, a heat sink or a mechanical device. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: the first aspect of the invention provides a flexible thermal interface material, which comprises a first metal layer, a composite material layer and a second metal layer which are sequentially stacked, wherein the composite material layer comprises a metal nano array, a graphene material and a polymer, the metal nano array is formed by a metal nano column array, the graphene material is distributed in the metal nano array, a three-dimensional network structure is formed between the graphene material and the metal nano array, pores are formed in the three-dimensional network structure, and the polymer is filled in the pores. The invention adopts the metal nano-array as a basic framework to realize high thermal conductivity in the vertical direction. And the graphene material grows on the surface of the metal nano array, so that the graphene material coats the metal nano array to form a protective layer and connects adjacent metal nano column materials, the transverse heat conduction is enhanced, and the metal nano array structure is protected from being corroded and oxidized. And filling the pores by penetrating the polymer, and realizing the efficient heat conduction effect of the thermal interface material by the synergistic effect among the metal nano array, the graphene material and the polymer, so that the thermal interface material has the advantages of ultralow thermal resistance, high flexibility, oxidation resistance, corrosion resistance and the like. Preferably, one end of the metal nano-pillar is connected with the first metal layer, and the other end of the metal nano-pillar is connected with the second metal layer. Preferably, the thermal interface material has a thickness of 20 μm to 800. Mu.m, more preferably, the thermal interface material has a thickness of 20 μm to 400. Mu.m, still more preferably, the thermal interface material has a thickness of 20 μm to 200. Mu.m, still more preferably, the thermal interface material has a thickness of 20 μm to 100. Mu.m, and still more preferably, the thermal interface material has a thickness of 20 μm to 40. Mu.m. The thermal interface material has adjustable overall thickness, and can realize the heat transfer effect with ultra-high performance with very low thickness. Preferably, the thickness of the first metal layer is 100 nm-10 μm. The f