Thermal interface material and preparation method thereof, and thermal management component

Abstract

The present invention relates to a thermal interface material, comprising a polymer matrix layer, a heat-conducting layer, and a metal layer, wherein the polymer matrix layer has pores, the heat-conducting layer is adhered to the polymer matrix layer, and the heat-conducting layer and the polymer matrix layer are simultaneously coiled to form a core, and the metal layer is arranged on the end face of the core and is used to seal the end face of the core. The present invention also relates to a method for preparing a thermal interface material and a thermal management component using the thermal interface material. The thermal interface material of the present invention has good compressibility and thermal conductivity. At the same time, the thermal interface material of the present invention can effectively reduce the contact thermal resistance with the heating device and the heat dissipation device. Therefore, when the thermal interface material is used in a thermal management component, the heat generated by the heating device can be effectively conducted to the heat dissipation device through the thermal interface material.

Description

Technical Field

[0001] The present invention relates to the field of heat dissipation technology, and in particular to a thermal interface material, a preparation method thereof, and a thermal management component. Background Art

[0002] Traditional thermal interface materials primarily incorporate high-thermal-conductivity ceramic fillers such as boron nitride, aluminum nitride, and aluminum oxide into a polymer matrix. These materials typically have thermal conductivities ranging from 1W / (m·K) to 5W / (m·K), making them inadequate for addressing the heat dissipation challenges associated with high-power, high-density packaging in the electronics industry. While graphene-based thermal interface materials can achieve thermal conductivities as high as 615W / (m·K), their Young's modulus is as high as 500MPa, making them difficult to meet the demands of thermal interface materials.

[0003] In addition, in the actual packaging of electronic devices, it is difficult for thermal interface materials to achieve perfect physical contact with electronic components and heat sinks. There are still some tiny air gaps between the thermal interface materials and electronic components and heat sinks. The thermal conductivity of air is only 0.024W / (m·K), which is a poor conductor of heat. This will result in the thermal interface materials that are not in direct contact with electronic components and heat sinks not being able to exert their heat transfer performance, ultimately resulting in a particularly large contact thermal resistance of the entire thermal interface material, and heat cannot be effectively transferred from the electronic components to the heat sink through the thermal interface material. Summary of the Invention

[0004] Based on this, it is necessary to provide a thermal interface material with high thermal conductivity, low contact thermal resistance and good compressibility and a preparation method thereof, as well as a thermal management component composed of the thermal interface material to address the above problems.

[0005] A thermal interface material comprises a polymer matrix layer, a heat-conducting layer, and a metal layer. The polymer matrix layer has pores, the heat-conducting layer is adhered to the polymer matrix layer, and the heat-conducting layer and the polymer matrix layer are simultaneously coiled to form a core. The metal layer is arranged on the end face of the core and is used to seal the end face of the core.

[0006] In one embodiment, the thickness of the polymer matrix layer is 100 μm-1000 μm.

[0007] In one embodiment, the porosity of the polymer matrix layer is greater than or equal to 90%.

[0008] In one embodiment, the polymer matrix layer includes at least one of polyurethane foam tape, melamine foam tape, and polyethylene foam tape.

[0009] In one embodiment, the thickness of the heat-conducting layer is 20 μm-50 μm, and the heat-conducting layer includes a graphene layer.

[0010] In one embodiment, the thickness of the metal layer is 20 nm-200 nm, and the metal layer includes at least one of a gold layer, a silver layer, a copper layer, and an aluminum layer.

[0011] In one embodiment, the core is circular or polygonal.

[0012] In one embodiment, the core is in a spiral or concentric circle shape.

[0013] A method for preparing the thermal interface material as described above comprises:

[0014] Laminating the heat conductive layer and the polymer matrix layer and then coiling them to obtain a core;

[0015] The metal layer is transferred to the end surface of the core body by a wet transfer method to obtain a thermal interface material.

[0016] A thermal management component includes a heating device, a heat dissipation device and the thermal interface material as described above, wherein the thermal interface material is arranged between the heating device and the heat dissipation device, and the core of the thermal interface material is perpendicular to the heating device and the heat dissipation device.

[0017] The thermal interface material of the present invention, on the one hand, has pores in the polymer matrix layer, and on the other hand, the polymer matrix layer and the thermally conductive layer are bonded and coiled to form a core, which makes the core highly compressible. During compression, the material partially fills the pores, ultimately resulting in a zero Poisson's ratio in the core, preventing core fracture and separation of the metal layer from the core. Therefore, the thermal interface material of the present invention has excellent compressibility and thermal conductivity.

[0018] At the same time, the metal layer in the thermal interface material also has high thermal conductivity, which can effectively reduce the contact thermal resistance between the thermal interface material and the heating device and the heat dissipation device. Therefore, when the thermal interface material is used in the thermal management component, the heat generated by the heating device can be effectively conducted to the heat dissipation device through the thermal interface material. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic structural diagram of a thermal interface material according to an embodiment of the present invention;

[0020] Figure 2 A top view of a core of an embodiment of the thermal interface material of the present invention;

[0021] Figure 3 This is a compressive stress-strain curve of the thermal interface material obtained in Example 2 of the present invention;

[0022] Figure 4 This is a photograph of the core obtained in Comparative Example 3 of the present invention.

[0023] In the figure: 10, metal layer; 20, core; 201, polymer matrix layer; 202, thermal conductive layer. DETAILED DESCRIPTION

[0024] The thermal interface material, preparation method thereof, and thermal management component provided by the present invention will be further described below.

[0025] like Figure 1 As shown, a thermal interface material according to an embodiment of the present invention includes a polymer matrix layer 201, a heat-conducting layer 202, and a metal layer 10. The polymer matrix layer 201 has pores, and the heat-conducting layer 202 is adhered to the polymer matrix layer 201. Moreover, the heat-conducting layer 202 and the polymer matrix layer 201 are simultaneously coiled to form a core 20. The metal layer 10 is arranged on the end face of the core 20 and is used to seal the end face of the core 20.

[0026] In the core 20 formed by winding the heat-conducting layer 202 and the polymer matrix layer 201 simultaneously, the outer side of the core 20 may be the heat-conducting layer 202 or the polymer matrix layer 201 , preferably the polymer matrix layer 201 .

[0027] Since graphene has an extremely high thermal conductivity, in one or more embodiments, the heat conducting layer 202 is preferably a graphene layer. Considering the compressibility and thermal conductivity of the core 20, the thickness of the heat conducting layer 202 is preferably 20 μm-50 μm.

[0028] Since the polymer matrix layer 201 contains pores, it can provide good compressibility for the core 20 . In order to ensure the compressibility of the core 20 , the porosity of the polymer matrix layer 201 is preferably greater than or equal to 90%.

[0029] In one or more embodiments, the polymer base layer 201 includes at least one of polyurethane foam tape, melamine foam tape, and polyethylene foam tape, thereby ensuring the bonding strength between the polymer base layer 201 and the thermal conductive layer 202 .

[0030] Considering that when the thickness of the polymer matrix layer 201 is too thin, compressibility is affected, and when it is too thick, the proportion of the heat conductive layer 202 in the core 20 is too small, affecting thermal conductivity, the thickness of the polymer matrix layer 201 is preferably 100 μm-1000 μm.

[0031] Thus, by laminating and coiling the thermally conductive layer 202 and the polymer matrix layer 201 to form the core 20, the resulting core 20 has a Young's modulus of 15 MPa-70 MPa, exhibiting good compressibility. During compression, the material partially fills the pores, ultimately resulting in the core 20 exhibiting a zero Poisson's ratio. Furthermore, the polymer matrix layer 201 and the thermally conductive layer 202 are laminated and coiled to form the core 20. This prevents the core 20 from breaking and prevents the metal layer 10 from peeling off from the core 20, compared to a core formed by stacking the polymer matrix layer 201 and the thermally conductive layer 202.

[0032] In one or more embodiments, the core 20 is cylindrical or prismatic, such as triangular prism, quadrangular prism, etc., preferably cylindrical. Further, the core 20 is spiral or concentric, preferably as Figure 2 The spiral shape shown, wherein the specific dimensional parameters such as diameter and height can be adjusted according to the application field.

[0033] Because the in-plane thermal conductivity of the graphene layer is much greater than its out-of-plane thermal conductivity, to achieve a thermal interface material with high thermal conductivity, the core 20 is positioned perpendicular to the heating and cooling components during use. To reduce the contact thermal resistance between the thermal interface material and the heating and cooling components, the end faces of the core 20 are sealed with a metal layer 10 with excellent thermal conductivity.

[0034] It can be understood that both end surfaces of the core 20 are sealed with the metal layer 10 . After closure, the heat-conducting layer 202 in the core 20 is perpendicular to the metal layer 10 .

[0035] Considering that it is difficult to reduce the contact thermal resistance when the metal layer 10 is too thin, and the intrinsic thermal resistance of the metal layer 10 is large when it is too thick, which is not conducive to reducing the contact thermal resistance, the thickness of the metal layer 10 is preferably 20nm-200nm, and the metal layer 10 within this thickness range can be directly adhered to the core 20 through van der Waals force without the need for adhesives, etc., and will not affect the heat conduction between the metal layer 10 and the thermal conductive layer 202.

[0036] In one or more embodiments, the metal layer 10 includes at least one of a gold layer, a silver layer, a copper layer, and an aluminum layer.

[0037] The present invention also provides a method for preparing the thermal interface material as described above, comprising:

[0038] S1, laminating the heat conductive layer 202 and the polymer matrix layer 201 and then coiling them to obtain the core 20;

[0039] S2, transferring the metal layer 10 to the end surface of the core 20 by a wet transfer method to obtain a thermal interface material.

[0040] The present invention also provides a thermal management component, including a heating device, a heat dissipation device and the thermal interface material as described above, wherein the thermal interface material is arranged between the heating device and the heat dissipation device, and the core of the thermal interface material is perpendicular to the heating device and the heat dissipation device.

[0041] In one or more embodiments, the heating device is an electronic component.

[0042] The thermal interface material of the present invention has good compressibility and thermal conductivity. At the same time, it can effectively reduce the contact thermal resistance between the thermal interface material and the heating device and the heat dissipation device. Therefore, when the thermal interface material is used in a thermal management component, the heat generated by the heating device can be effectively transferred to the heat dissipation device through the thermal interface material.

[0043] Hereinafter, the thermal interface material and its preparation method, and the thermal management component will be further described through the following specific embodiments.

[0044] Example 1

[0045] Graphene paper with a thickness of 25 μm and polyurethane foam tape with a thickness of 450 μm and a porosity of 95% were adhered together, then cut into narrow strips with a thickness of 1.56 mm, and the narrow strips were coiled into a disk-shaped core with a diameter of 3 cm.

[0046] A 70nm thick gold foil was first floated on the water surface, and then the gold foil was transferred to the upper and lower end surfaces of the disc-shaped core using a wet transfer method and dried to obtain a thermal interface material.

[0047] The thermal conductivity of the thermal interface material obtained in this embodiment is 267W / (m·K), the Young's modulus is 30MPa, the Poisson's ratio is 0, and the contact thermal resistance at 30% strain is 0.41K·cm 2 / W.

[0048] Example 2

[0049] Graphene paper with a thickness of 25 μm and polyurethane foam tape with a porosity of 95% and a thickness of 450 μm were adhered together, then cut into 2.9 mm thick strips, and the strips were coiled into a disk-shaped core with a diameter of 3 cm.

[0050] A 70nm thick gold foil was first floated on the water surface, and then the gold foil was transferred to the upper and lower end surfaces of the disc-shaped core using a wet transfer method and dried to obtain a thermal interface material.

[0051] The thermal conductivity of the thermal interface material obtained in this embodiment is 270W / (m·K), the Young's modulus is 30MPa, the Poisson's ratio is 0, and the contact thermal resistance at 30% strain is 0.41K·cm 2 / W.

[0052] Figure 3 The compressive stress-strain curve of the thermal interface material obtained in this embodiment is shown in FIG. Figure 3 It can be seen that within the strain range of 10%-50%, the stress of the thermal interface material is only 0.35 MPa-0.43 MPa (50 psi-62 psi). Therefore, the thermal interface material has good compressibility.

[0053] Example 3

[0054] Graphene paper with a thickness of 50 μm and polyurethane foam tape with a porosity of 95% and a thickness of 450 μm were adhered together, then cut into narrow strips with a thickness of 1.56 mm, and the narrow strips were coiled into a disk-shaped core with a diameter of 3 cm.

[0055] A 70nm thick gold foil was first floated on the water surface, and then the gold foil was transferred to the upper and lower end surfaces of the disc-shaped core using a wet transfer method and dried to obtain a thermal interface material.

[0056] The thermal conductivity of the thermal interface material obtained in this embodiment is 285W / (m·K), the Young's modulus is 70MPa, the Poisson's ratio is 0, and the contact thermal resistance at 30% strain is 0.35K·cm 2 / W.

[0057] Example 4

[0058] Graphene paper with a thickness of 25 μm and polyurethane foam tape with a thickness of 900 μm and a porosity of 95% were adhered together, then cut into narrow strips with a thickness of 1.56 mm, and the narrow strips were coiled into a disk-shaped core with a diameter of 3 cm.

[0059] A 70nm thick gold foil was first floated on the water surface, and then the gold foil was transferred to the upper and lower end surfaces of the disc-shaped core using a wet transfer method and dried to obtain a thermal interface material.

[0060] The thermal conductivity of the thermal interface material obtained in this embodiment is 245W / (m·K), the Young's modulus is 15MPa, the Poisson's ratio is 0, and the contact thermal resistance at 30% strain is 0.49K·cm 2 / W.

[0061] Example 5

[0062] Graphene paper with a thickness of 25 μm and polyurethane foam tape with a thickness of 450 μm and a porosity of 95% were adhered together, then cut into narrow strips with a thickness of 1.56 mm, and the narrow strips were coiled into a disk-shaped core with a diameter of 3 cm.

[0063] A 100nm thick silver foil was first floated on the water surface, and then the gold foil was transferred to the upper and lower end surfaces of the disc-shaped core using a wet transfer method and dried to obtain a thermal interface material.

[0064] The thermal conductivity of the thermal interface material obtained in this embodiment is 265W / (m·K), the Young's modulus is 30MPa, the Poisson's ratio is 0, and the contact thermal resistance at 30% strain is 0.40K·cm 2 / W.

[0065] Comparative Example 1

[0066] A 25 μm thick graphene paper and a 450 μm thick polyurethane foam tape with a porosity of 95% were bonded together, then cut into 1.56 mm thick strips, and the strips were coiled into a disk-shaped core with a diameter of 3 cm to obtain a thermal interface material.

[0067] The thermal conductivity of the thermal interface material obtained in this comparative example is 276W / (m·K), the Young's modulus is 30MPa, the Poisson's ratio is 0, and the contact thermal resistance at 30% strain is 0.66K·cm 2 / W.

[0068] Comparative Example 2

[0069] A 25 μm thick graphene paper and a 450 μm thick polyurethane foam tape with a porosity of 95% were bonded together, then cut into 3.56 mm thick strips, and the strips were coiled into a disk-shaped core with a diameter of 3 cm to obtain a thermal interface material.

[0070] The thermal conductivity of the thermal interface material obtained in this comparative example is 278W / (m·K), the Young's modulus is 30MPa, the Poisson's ratio is 0, and the contact thermal resistance at 30% strain is 0.66K·cm 2 / W.

[0071] Comparative Example 3

[0072] Graphene paper with a thickness of 25 μm and polyurethane foam tape with a thickness of 450 μm and a porosity of 95% were bonded together and then cut into a core with a thickness of 3.56 mm. Figure 4 As shown, the core obtained in this comparative example is easily delaminated and broken.

[0073] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0074] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A thermal interface material, characterized in that: The thermal interface material includes a polymer base layer, a heat-conducting layer and a metal layer, wherein the polymer base layer has pores, the heat-conducting layer is adhered to the polymer base layer, and the heat-conducting layer and the polymer base layer are simultaneously coiled to form a core, and the metal layer is arranged on the end surface of the core and is used to seal the end surface of the core, wherein the thickness of the polymer base layer is 100μm-1000μm; the porosity of the polymer base layer is greater than or equal to 90%, and the polymer base layer includes at least one of polyurethane foam tape, melamine foam tape, and polyethylene foam tape; the thickness of the heat-conducting layer is 20μm-50μm, and the thickness of the metal layer is 20nm-200nm; the Young's modulus of the core is 15MPa-70MPa, and when compressed, the core exhibits a zero Poisson's ratio.

2. The thermal interface material according to claim 1, wherein The heat conducting layer includes a graphene layer.

3. The thermal interface material according to claim 1, wherein The metal layer includes at least one of a gold layer, a silver layer, a copper layer, and an aluminum layer.

4. The thermal interface material according to claim 1, wherein The core is cylindrical or prismatic.

5. The thermal interface material according to claim 4, characterized in that The core is in the shape of a spiral column or a concentric cylinder.

6. A method for preparing a thermal interface material according to any one of claims 1 to 5, characterized in that: include: Laminating the heat conductive layer and the polymer matrix layer and then coiling them to obtain a core; as well as The metal layer is transferred to the end surface of the core body by a wet transfer method to obtain a thermal interface material.

7. A thermal management component, characterized in that It comprises a heating device, a heat dissipation device and the thermal interface material according to any one of claims 1 to 5, wherein the thermal interface material is arranged between the heating device and the heat dissipation device, and the core of the thermal interface material is perpendicular to the heating device and the heat dissipation device.

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