Composite thermal interface material and preparation method and application thereof

Abstract

The application discloses a composite thermal interface material and a preparation method and application thereof. The composite thermal interface material comprises a composite graphene layer, and the composite graphene layer comprises a first graphene layer, a porous material layer and a second graphene layer which are sequentially arranged. The porous material layer is filled with acidized graphene. The acidized graphene in the porous material layer is connected and overlapped with each other in the pores of the porous material layer, so as to construct a three-dimensional heat conduction channel.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of thermal interface materials, in particular to a composite thermal interface material and a preparation method and application thereof. BACKGROUND

[0002] Heat dissipation has always been a key research work in the electronic industry, and the actual working temperature of electronic components is one of the key factors affecting their reliability. With the development of electronic devices towards miniaturization and high power consumption, the power density gradually increases, and the heat dissipation of electronic devices also increases exponentially, which also puts higher requirements on the heat dissipation performance of the system. The thermal interface material is a key material of the heat dissipation system, and is a bridge for heat transfer between the chip and the heat sink. According to the different fillers and production processes of the thermal conductive material, the thermal conductivity of the thermal interface material also shows great differences.

[0003] The existing thermal interface material disperses particles with high thermal conductivity in a polymer matrix to form a composite material, such as graphite, boron nitride, silicon oxide, aluminum oxide, silver or other metals, etc. The common defect of this kind of material is that the overall material thermal conductivity is small, generally 1 W / m·K, which cannot meet the demand of the improvement of semiconductor integration level on heat dissipation. Increasing the content of the thermal conductive particles of the polymer matrix, so that the particles are in contact with each other as much as possible, can increase the thermal conductivity of the entire composite material, such as some special interface materials, which can reach 4-8 W / (m·K). However, when the content of the thermal conductive particles of the polymer matrix increases to a certain extent, the performance of the polymer matrix will change, such as the oil will become hard, thereby the wetting effect will become poor, and the rubber will also become hard and lose its flexibility, greatly reducing the interface contact performance of the thermal interface material, thereby increasing the thermal resistance between the heat sink and the semiconductor device.

[0004] Therefore, there is an urgent need for a new type of thermal interface material to solve the above problems. SUMMARY

[0005] The first technical problem to be solved by the present application is:

[0006] To solve the first technical problem, the technical scheme adopted by the present application is:

[0007] The second technical problem to be solved by the present application is:

[0008] To solve the second technical problem, the technical scheme adopted by the present application is:

[0009] The third technical problem to be solved by the present application is:

[0010] The application of the composite thermal interface material.

[0011] To solve the third technical problem, the technical scheme adopted by the present application is:

[0012] A composite thermal interface material, comprising a composite graphene layer;

[0013] The composite graphene layer comprises, in sequence:

[0014] a first graphene layer;

[0015] a porous material layer;

[0016] a second graphene layer;

[0017] The porous material layer is filled with acidized graphene.

[0018] According to an embodiment of the present application, one of the technical solutions has at least one of the following advantages or beneficial effects:

[0019] 1. The porous material layer is filled with acidized graphene, which is connected and overlapped with each other in the pores of the porous material layer, thereby constructing a three-dimensional heat conduction channel.

[0020] 2. The first graphene layer and the second graphene layer sandwich the porous material layer, so that the three-dimensional heat conduction channel in the porous material layer is further extended to form a huge heat conduction network.

[0021] 3. The composite graphene layer constructs a huge heat conduction network. Since the porous material layer is included in the middle and only graphene layers are included on both sides, the heat in the middle of the heat conduction network tends to be conducted to both sides in actual use, thereby accelerating the rate of heat conduction.

[0022] According to an embodiment of the present application, the thickness of the composite graphene layer is 70-500 μm.

[0023] According to an embodiment of the present application, the porous material used in the porous material layer comprises at least one of porous ceramic and molecularly imprinted polymer.

[0024] According to an embodiment of the present application, the porous ceramic comprises at least one of silica ceramic, alumina ceramic, magnesium silicate ceramic, and zirconia ceramic.

[0025] According to an embodiment of the present application, the first graphene layer and the second graphene layer comprise the following components: graphene oxide and cellulose adsorbed on the surface of the graphene oxide. The addition of cellulose in graphene oxide is conducive to the formation of a heat conduction network.

[0026] To solve the second technical problem, the technical solution adopted by the present application is:

[0027] A method for preparing the composite thermal interface material, comprising the following steps:

[0028] S1 applying acidized graphene on a porous material to obtain a porous material layer;

[0029] S2 applying graphene paste on both sides of the porous material layer respectively to obtain the composite thermal interface material.

[0030] According to an embodiment of the present application, the preparation of the acidized graphene comprises the following steps: mixing inorganic acid with graphene, reacting to obtain the graphene paste.

[0031] According to an embodiment of the present application, the preparation of the graphene paste in step S2 comprises the following steps: mixing graphene oxide, cellulose material, anionic surfactant and dispersant, and ultrasonicating to obtain the graphene paste. This step makes the graphene layer formed by the graphene paste a surface passivated graphene, which can avoid the rolling and stacking of the graphene layer.

[0032] According to an embodiment of the present application, the weight ratio of the inorganic acid to the graphene is 10-50:2-5.

[0033] According to an embodiment of the present application, the step S2 further comprises a heating step, and the heating temperature is 200-800℃.

[0034] According to an embodiment of the present application, the step S1 further comprises a vacuumizing or negative pressure adsorbing step, so that the acidized graphene is adsorbed into the pores of the porous material layer.

[0035] Another aspect of the present application also relates to the application of the composite thermal interface material in an electronic screen. The composite thermal interface material comprises the embodiments of the first aspect as described above. Since the application adopts all the technical solutions of the composite thermal interface material of the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments.

[0036] Other features and advantages of the present application will be set forth in the following description, and in part will become apparent from the description, or can be learned by practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0037] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description, taken in conjunction with the accompanying drawings, in which:

[0038] Figure 1 Structure schematic diagram of the composite thermal interface material of Example 1.

[0039] Reference signs:

[0040] 100 - composite graphene layer, 200 - first graphene layer, 300 - porous material layer, 400 - second graphene layer. DETAILED DESCRIPTION

[0041] Embodiments of the present application are described below in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference signs represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by reference to the accompanying drawings are exemplary and are for the purpose of explanation only, and are not to be understood as limiting the present application.

[0042] In the description of the present application, if there is a description to first, second, etc., it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or the order of indicated technical features.

[0043] In the description of the present application, it is to be understood that the orientation description, such as up, down, etc., indicates the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, only for the purpose of facilitating the description of the present application and simplifying the description, and is not to be understood as indicating or implying that the device or element indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0044] In the description of the present application, it is to be understood that, unless otherwise explicitly limited, the words such as setting, installing, connecting, etc. should be broadly understood, and the person skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical solution.

[0045] The technical solutions in the embodiments of the present application will be described below in conjunction with the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by the person skilled in the art without creative labor are within the scope of the present application.

[0046] In the examples and comparative examples, the porous material is a silica porous material.

[0047] Example 1

[0048] A composite thermal interface material, comprising a composite graphene layer 100;

[0049] The composite graphene layer 100 comprises, which are sequentially stacked:

[0050] The first graphene layer 200;

[0051] The porous material layer 300;

[0052] a second graphene layer 400;

[0053] The porous material layer is filled with acidized graphene.

[0054] A method for preparing the composite thermal interface material, comprising the following steps:

[0055] A1 Preparing acidized graphene: mixing 150 mL of concentrated sulfuric acid with 1.5 g of graphene, treating at 60°C for 1 hour, washing with deionized water, drying, and obtaining acidized graphene.

[0056] A2 Preparing the porous material layer 300: coating the acidized graphene obtained in step A1 on a porous ceramic, heating at 800°C in a nitrogen environment for 5 hours, and vacuum drying to obtain the porous material layer 300.

[0057] A3 Preparing the first graphene layer 200: mixing 1.5 parts by weight of graphene oxide, 0.1 parts by weight of cellulose, 0.2 parts by weight of sodium dodecyl sulfate, and 0.1 parts by weight of polyvinyl alcohol in water, stirring, coating on one side of the surface of the porous material layer 300, and drying to obtain the first graphene layer 200.

[0058] A4 Preparing the second graphene layer 400: mixing 1.5 parts by weight of graphene oxide, 0.1 parts by weight of cellulose, 0.2 parts by weight of sodium dodecyl sulfate, and 0.1 parts by weight of polyvinyl alcohol in water, stirring, coating on the other side of the surface of the porous material layer 300, and drying to obtain the composite thermal interface material.

[0059] Example 2

[0060] Example 2 differs from Example 1 in that the composite thermal interface material of Example 2 does not include cellulose in the first graphene layer 200 and the second graphene layer.

[0061] A composite thermal interface material, comprising a composite graphene layer 100;

[0062] The composite graphene layer 100 comprises, in sequence:

[0063] A first graphene layer 200;

[0064] A porous material layer 300;

[0065] A second graphene layer 400;

[0066] The porous material layer 300 is filled with acidized graphene.

[0067] A method for preparing the composite thermal interface material, comprising the following steps:

[0068] A1: Preparation of acidized graphene: 150 mL of concentrated sulfuric acid was mixed with 1.5 g of graphene, and treated at 60°C for 1 hour, washed with deionized water, dried, to obtain acidized graphene.

[0069] A2: Preparation of the porous material layer 300: The acidized graphene obtained in step A1 was coated on a porous ceramic, heated at 800°C in a nitrogen atmosphere for 5 hours, vacuum dried, to obtain the porous material layer.

[0070] A3: Preparation of the first graphene layer 200: 1.5 parts by weight of graphene oxide, 0.2 parts by weight of sodium dodecyl sulfate, and 0.1 parts by weight of polyvinyl alcohol were mixed in water, and after stirring, coated on one side of the surface of the porous material layer 300, dried, to obtain the first graphene layer 200.

[0071] A4: Preparation of the second graphene layer 400: 1.5 parts by weight of graphene oxide, 0.2 parts by weight of sodium dodecyl sulfate, and 0.1 parts by weight of polyvinyl alcohol were mixed in water, and after stirring, coated on the other side of the surface of the porous material layer 300, dried, to obtain the composite thermal interface material.

[0072] Comparative Example 1

[0073] Comparative Example 1 differs from Example 1 in that Comparative Example 1 does not have the first graphene layer 200 and the second graphene layer 400.

[0074] A composite thermal interface material, comprising a composite graphene layer 100;

[0075] The above-mentioned composite graphene layer 100 comprises, which are sequentially stacked:

[0076] a porous material layer 300;

[0077] The above-mentioned porous material layer 300 is filled with acidized graphene.

[0078] A method for preparing a thermal interface material, comprising the following steps:

[0079] A1: Preparation of acidized graphene: 150 mL of concentrated sulfuric acid was mixed with 1.5 g of graphene, and treated at 60°C for 1 hour, washed with deionized water, dried, to obtain acidized graphene.

[0080] A2: Preparation of the porous material layer 300: The acidized graphene obtained in step A1 was coated on a porous ceramic, heated at 800°C in a nitrogen atmosphere for 5 hours, vacuum dried, to obtain the composite thermal interface material.

[0081] Comparative Example 2

[0082] Comparative Example 2 differs from Example 1 in that the porous material layer of Comparative Example 2 is not filled with acidized graphene.

[0083] A composite thermal interface material comprising a composite graphene layer 100;

[0084] The composite graphene layer 100 comprises, in sequence:

[0085] a first graphene layer 200;

[0086] a porous material layer 300;

[0087] a second graphene layer 400.

[0088] A method for preparing a thermal interface material, comprising the following steps:

[0089] A1 Preparing the first graphene layer 200: mixing 1.5 parts by weight of graphene oxide, 0.1 parts by weight of cellulose, 0.2 parts by weight of sodium dodecyl sulfate and 0.1 parts by weight of polyvinyl alcohol in water, stirring, coating on one side of the surface of the porous material layer 300, drying to obtain the first graphene layer 200.

[0090] A2 Preparing the second graphene layer 400: mixing 1.5 parts by weight of graphene oxide, 0.1 parts by weight of cellulose, 0.2 parts by weight of sodium dodecyl sulfate and 0.1 parts by weight of polyvinyl alcohol in water, stirring, coating on the other side of the surface of the porous material layer 300, drying to obtain the composite thermal interface material.

[0091] Performance test:

[0092] The composite thermal interface material prepared in Examples 1-2 and the thermal interface material prepared in Comparative Examples 1-2 were taken for thermal conductivity and hardness tests, and the test results are shown in Table 1.

[0093] Table 1

[0094] Thermal conductivity (W / m-K) Hardness (Shore C) Example 1 38.8 49 Example 2 35.5 49 Example 3 30.0 49 Comparative Example 1 21.8 48 Comparative Example 2 23.4 49

[0095] The thermal conductivity test refers to GB / T10294.

[0096] The test method of Shore hardness: a Shore hardness tester is inserted into the measured material, a pointer on the dial is connected to a thorn through a spring, the thorn is inserted into the surface of the measured material, and the value displayed on the dial is the hardness value.

[0097] The above is only an embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent transformation or direct or indirect application in related technical fields based on the content of the present application is also included in the patent protection scope of the present application.

Claims

1. A composite thermal interface material, characterized by: The composite graphene layer (100) comprises, in sequence: The composite graphene layer (100) comprises, in sequence: A first graphene layer (200); A porous material layer (300); A second graphene layer (400); The porous material layer (300) is filled with acidified graphene, which is prepared by reacting graphene with inorganic acid, and the acidified graphene is connected and overlapped with each other in the pores of the porous material layer, thereby constructing a three-dimensional heat conduction channel. The first graphene layer (200) and the second graphene layer (400) comprise the following components: graphene oxide and cellulose adsorbed on the surface of the graphene oxide.

2. The composite thermal interface material of claim 1, wherein: The thickness of the composite graphene layer (100) is 70-500 μm.

3. The composite thermal interface material of claim 1, wherein: The porous material used in the porous material layer (300) comprises at least one of porous ceramic and molecularly imprinted polymer.

4. A method of making a composite thermal interface material as claimed in any one of claims 1 to 3, characterised by: The method comprises the following steps: S1: coating acidified graphene on a porous material to obtain the porous material layer (300); S2: coating graphene paste on both sides of the porous material layer (300) to obtain the first graphene layer (200) and the second graphene layer (400), thereby obtaining the composite thermal interface material.

5. The method of claim 4, wherein: The preparation of the acidified graphene comprises the following steps: mixing inorganic acid with graphene, and reacting to obtain the graphene paste.

6. The method of claim 5, wherein: The weight ratio of the inorganic acid to the graphene is 10-50:2-5.

7. The method of claim 4, wherein: In step S2, a heating step is further included, and the heating temperature is 200-800℃.

8. The method of claim 4, wherein: In step S1, a step of vacuum extraction or negative pressure adsorption is further included, so that the acidified graphene is adsorbed into the pores of the porous material layer (300).

9. Use of the composite thermal interface material according to any one of claims 1 to 3 in an electronic screen.

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