WO2024008020A1

WO2024008020A1 - Carbon fiber heat-conducting phase-change composite material and preparation method therefor

Info

Publication number: WO2024008020A1
Application number: PCT/CN2023/105227
Authority: WO
Inventors: 曹勇; 孙爱祥; 羊尚强; 方晓
Original assignee: 深圳市鸿富诚新材料股份有限公司
Priority date: 2022-07-07
Filing date: 2023-06-30
Publication date: 2024-01-11
Also published as: CN115139581A

Abstract

The present invention relates to the field of thermal interface materials, and in particular to a carbon fiber heat-conducting phase-change composite material and a preparation method therefor. The carbon fiber heat-conducting phase-change composite material comprises a heat-conducting layer and heat-conducting phase-change layers arranged on two sides of the heat-conducting layer. The heat-conducting layer comprises the following raw materials in parts by weight: 100-700 parts of a carbon fiber, 150-1,700 parts of heat-conducting powder, 50-120 parts of silicone oil, 0.3-2 parts of a coupling agent, 1-4 parts of a curing agent, 0.1-1 part of an inhibitor, and 1-4 parts of a catalyst. Each heat-conducting phase-change layer comprises the following raw materials in parts by weight: 170-190 parts of aluminum powder, 2-20 parts of zinc oxide, 1-8 parts of a coupling agent, 2-10 parts of a phase-change material, and 2-5 parts of an antioxidant. The heat-conducting phase-change layers are located on the two sides of the heat-conducting layer perpendicular to the axial direction of heat-conducting fibers. According to the present application, the contact thermal resistance of the carbon fiber heat-conducting phase-change composite material on an interface of contact between a heating device and a heat dissipation device can be effectively reduced, and then a more efficient heat-conducting effect can be achieved.

Description

A carbon fiber thermally conductive phase change composite material and its preparation method

Technical field

The present application relates to the field of thermal interface materials, and in particular to a carbon fiber thermally conductive phase change composite material and a preparation method thereof.

Background technique

With the advent of the 5G era, the operating frequency of electronic chips continues to increase, and the heat flow density continues to increase, causing the heat generation of electronic equipment to also increase significantly. If the heat generated during the operation of electronic equipment is not transferred to the cooling end in time and dissipated, long-term accumulation of heat will cause the electronic equipment to malfunction and even shorten its service life. In order to solve the heat dissipation problem of electronic products, thermal interface materials came into being.

Thermal interface material is a general term for materials that are coated between heat dissipation devices and heating devices to reduce the contact thermal resistance between heat dissipation devices and heating devices. Thermal interface materials have high thermal conductivity, high flexibility and good insulation. They are easy to install and removable. They can fill small or large gaps and have a wide range of applications. Currently commonly used thermal interface materials mainly include silicone, silicone grease, heat dissipation pads, thermally conductive glue, thermally conductive metal sheets and other materials. Carbon fiber stands out among thermal interface materials because of its low density, excellent mechanical properties, small thermal expansion coefficient, good thermal and electrical conductivity, high temperature resistance, fatigue resistance and other excellent properties. Carbon fiber is anisotropic and has excellent thermal conductivity in its axial direction. Thermal conductive pads made with it have low thermal resistance and can be widely used in high-tech fields such as aerospace, national defense and civil industry.

At present, carbon fiber thermal pads are mostly prepared by mechanically oriented slicing. The surface of the produced carbon fiber thermal pads is relatively rough, and there are bulges in parts of the carbon fiber thermal pads; and the wettability of the surfaces of carbon fibers and electronic devices such as chips Relatively poor, resulting in contact interface contact The thermal resistance is relatively high, which affects the thermal conductivity of the carbon fiber thermal pad.

Contents of the invention

In order to reduce the thermal contact resistance of the interface used by the carbon fiber thermal pad and further improve the thermal conductivity of the carbon fiber thermal pad, this application provides a carbon fiber thermal phase change composite material and a preparation method thereof.

In the first aspect, this application provides a carbon fiber thermally conductive phase change composite material, adopting the following technical solution:

A carbon fiber thermally conductive phase change composite material, including a thermally conductive layer and thermally conductive phase change layers arranged on both sides of the thermally conductive layer;

The thermal conductive layer includes the following raw materials by weight: 100 to 700 parts of carbon fiber, 150 to 1700 parts of thermally conductive powder, 50 to 120 parts of silicone oil, 0.3 to 2 parts of coupling agent, 1 to 4 parts of curing agent, and 0.1 to 0.1 part of inhibitor. 1 part, 1 to 4 parts of catalyst;

The thermally conductive phase change layer includes the following raw materials by weight: 170 to 190 parts of aluminum powder, 2 to 20 parts of zinc oxide, 1 to 8 parts of coupling agent, 2 to 10 parts of phase change material, and 2 to 5 parts of antioxidant;

The thermally conductive phase change layer is located on both sides of the thermally conductive layer perpendicular to the axial direction of the thermally conductive fiber.

The thermally conductive phase change layer is made of thermally conductive phase change materials, of which aluminum powder and zinc oxide have good thermal conductivity; the shape of the phase change material changes due to temperature changes and can provide higher latent heat. The phase change material operates at lower temperatures. It is solid when the temperature rises and changes from solid to flowable liquid when the temperature rises. The carbon fiber thermally conductive phase change composite material in the above technical solution is applied to electronic products. When the chips and other devices of the electronic products are working and generating heat, the phase change material is heated and transformed into a liquid state, which has a certain fluidity and can better infiltrate the chips, etc. The surface of the device reduces the contact thermal resistance of the carbon fiber thermally conductive phase change composite material at the contact interface between the heating device and the heat dissipation device, which can achieve more efficient heat conduction. Effect.

The thermally conductive phase change layers are arranged at both ends of the thermally conductive layer in the direction in which the thermally conductive fibers are arranged. In this direction, the thermally conductive fibers have better heat conduction effects and can better conduct the heat generated by the heating devices of electronic products to the heat dissipation through the thermally conductive phase change layers. device to improve the thermal conductivity efficiency of thermally conductive phase change composite materials.

The diameter of the carbon fiber is preferably 5-20 μm, and the length is preferably 50-300 μm; the thermal conductivity of the carbon fiber is not less than 900W/(m·k).

The thermally conductive powder is preferably at least one of aluminum oxide, zinc oxide, magnesium oxide, aluminum nitride, graphite flakes, graphene, aluminum powder, copper powder and silver-coated aluminum powder; the average particle size of the thermally conductive powder is preferably It is 1~15μm.

Further preferably, the thermally conductive powder is a mixture of aluminum oxide, zinc oxide and aluminum nitride, and the mass ratio of the three is 1:1:1.

The mass ratio of carbon fiber to thermally conductive powder is preferably 1: (2-4.5); the diameter of carbon fiber is preferably 10-15 μm, and the average particle size of thermally conductive powder is preferably 8-12 μm.

By adopting the above technical solution and combining carbon fiber with thermally conductive powder, a high thermal conductivity effect inside the thermally conductive layer is achieved. Carbon fiber exists in the form of long fibers inside the thermal conductive layer. The thermal conductive powder is granular and evenly distributed in the thermal conductive layer. While improving the overall thermal conductivity effect of the thermal conductive layer, it can also play a role in connecting the beginning and end of adjacent carbon fibers, which can be more The anisotropy of carbon fiber thermal conductivity can be fully utilized, so that the thermal conductivity performance of the thermal conductive layer in the axial direction of the carbon fiber can be further improved. Further optimizing the diameter of the carbon fiber and the particle size of the thermally conductive powder can not only improve the compatibility between the components of the thermally conductive layer, but also further improve the thermal conductivity of the thermally conductive layer.

The phase change material is preferably at least one of paraffin wax, microwax, silicone wax, polybutadiene, polyisoprene and hydroxyl-terminated polyisoprene.

The coupling agent in the thermally conductive layer is preferably a silane coupling agent containing vinyl functional groups; the coupling agent in the thermally conductive phase change layer is preferably long-chain alkyl silane, tetra-n-butyric acid titanate and triisostearic acid titanate. At least one of isopropyl esters.

In the thermal conductive layer, the curing agent is preferably hydrogen-containing silicone oil, the inhibitor is preferably ethynylcyclohexanol, and the catalyst is preferably a platinum catalyst.

In the thermally conductive phase change layer, the antioxidants are preferably 2,2-methylenebis(4-methyl-6-tert-butylphenol), 2,6-tertiary butyl-4-methylphenol and tetraphenyl At least one of diendylene glycol diphosphite esters.

The thickness of the thermal conductive layer is 100-500 μm, and the thickness of the thermal conductive phase change layer is 50-200 μm.

In the second aspect, this application provides a method for preparing carbon fiber thermally conductive phase change composite materials, adopting the following technical solution:

A method for preparing carbon fiber thermally conductive phase change composite materials, including the following steps:

Preparing the carbon fiber mixed base material: Mix the carbon fiber, thermally conductive powder, silicone oil, coupling agent, curing agent and inhibitor evenly, then add the catalyst and mix well to obtain the carbon fiber mixed base material;

Preparing the carbon fiber thermally conductive embryonic body: vacuuming the carbon fiber mixed base material. After the vacuuming process, the carbon fiber mixed base material is extruded through an automatic dispensing machine and arranged in the mold. After solidification, the thermally conductive silicone embryonic body is obtained;

Preparing the thermally conductive layer: Cut the thermally conductive silicone embryo into a specified thickness, and the cutting direction is perpendicular to the extrusion direction of the thermally conductive silicone embryo;

Preparing the thermally conductive phase change layer: Mix aluminum powder, zinc oxide, coupling agent, phase change material and antioxidant evenly to obtain a phase change material, and roll the phase change material to a specified thickness to obtain a phase change layer;

Preparation of carbon fiber thermally conductive phase change composite materials: Use a silica gel treatment agent to treat the surface of the thermally conductive layer, and then hot-press composite the thermally conductive layer and the thermally conductive phase change layer to prepare a carbon fiber thermally conductive phase change composite material.

When the uniformly mixed carbon fiber mixed base material is extruded on the extruder, the carbon fibers in the mixed base material will gradually be oriented along the extrusion direction with the extrusion flow of the mixed base material. The carbon fiber prepared by dispensing with a dispensing machine In the thermally conductive embryonic body, the axial direction of the carbon fiber is basically parallel to the extrusion direction of the thermally conductive embryonic body, and then the directional arrangement of the carbon fibers in the carbon fiber thermally conductive embryonic body is completed through the dispensing process of the dispensing machine, so that the carbon fiber thermally conductive embryonic body is in The thermal conductivity in the arrangement direction of carbon fibers is effectively improved. Vacuuming before preparing the carbon fiber thermally conductive embryonic body can effectively remove the gas in the carbon fiber mixture and avoid the existence of cavities formed by bubbles in the carbon fiber thermally conductive embryonic body extruded through the dispensing machine, which will affect its thermal conductivity.

The carbon fiber thermally conductive embryonic body prepared by the dispensing machine can be cut into thermally conductive layers of different thicknesses as required. The calendered thermally conductive phase change layer is hot-pressed and compounded on the thermally conductive layer on both sides perpendicular to the axial direction of the carbon fiber to form a sandwich structure. It becomes a carbon fiber thermal phase change composite material with good thermal conductivity. After it is applied to electronic products, the heat generated by the heating device of the electronic product can be quickly transferred to the heat dissipation device through the thermal conductive layer and dissipated; in addition, due to the directional arrangement of the carbon fibers in the thermal conductive layer, The thermally conductive phase change layer can be quickly heated to complete the morphological change and play a more efficient role in heat conduction and heat transfer.

In the step of preparing the phase change material, the raw materials are mixed evenly in an internal mixer. The internal mixing temperature is preferably 100 to 130°C, and the internal mixing time is preferably 0.5 to 1 hour; the calendering temperature is preferably 80 to 120°C, and the calendering speed is preferably 50 ~100㎜/min.

In the step of preparing the carbon fiber thermally conductive phase change composite material, the hot pressing temperature is preferably 90 to 110°C, and the hot pressing time is preferably 3 to 5 minutes.

To sum up, this application includes at least one of the following beneficial technical effects:

1. The carbon fiber thermally conductive phase change composite material provided in the technical solution of this application provides efficient thermal conductivity through the combination of carbon fiber and thermally conductive powder, and then sets thermally conductive phase change on both sides of the thermally conductive layer. layer, through the characteristics of the state change of the thermally conductive phase change layer after being heated, it can better infiltrate the surface of devices such as chips, reduce the contact thermal resistance of the carbon fiber thermally conductive phase change composite material at the contact interface of the heating device and the heat dissipation device, and can achieve a better Efficient heat conduction effect; and the thermal conductive phase change layer is set at both ends of the thermal conductive fiber arrangement direction on the thermal conductive layer. The thermal conductive fibers in this direction have better thermal conductivity and can better transfer the heat generated by the heating devices of electronic products through The thermally conductive phase change layer is conducted to the heat dissipation device to improve the thermal conductivity efficiency of the thermally conductive phase change composite material.

3. The carbon fiber thermally conductive phase change composite material provided by the technical solution of this application can achieve good adhesion between the thermally conductive layer and the thermally conductive phase change layer by adjusting the formula of the components and the processing technology. The prepared carbon fiber thermally conductive phase change composite material Has good structural stability.

2. The method for preparing the carbon fiber thermally conductive phase change composite material provided by the technical solution of this application is to prepare the thermally conductive layer through a dispensing machine. During the process of extruding the raw material of the thermally conductive layer through the dispensing machine, the carbon fiber is driven by the flowing mixture. Gradually adjust the swing direction and arrange it along the extrusion direction, so that the layers in the thermal conductive layer are uniformly arranged in the same direction, making full use of the high thermal conductivity of carbon fiber in the axial direction to prepare a thermal conductive layer with high thermal conductivity.

Description of the drawings

Figure 1 is a schematic diagram of the overall structure of a carbon fiber thermally conductive phase change composite material according to an embodiment of the present application.

Explanation of reference signs: 1. Thermal conductive layer; 2. Thermal conductive phase change layer.

Detailed ways

The present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that those that are not specified in the following examples are all carried out in accordance with conventional conditions or conditions recommended by the manufacturer; the raw materials used in the following examples can be obtained from commercially available sources unless otherwise specified.

Example

Examples 1-5

A carbon fiber thermally conductive phase change composite material. Its structure is as shown in Figure 1 and is prepared by the following method:

S1. According to the proportion in Table 1, add carbon fiber, thermally conductive powder, silicone oil, coupling agent, curing agent and inhibitor to the homogenizer and mix evenly, then add the catalyst and continue mixing evenly to obtain a carbon fiber mixed base material;

S2. Add the carbon fiber mixed base material to the glue storage barrel of the automatic dispensing machine. Put the glue storage barrel and the carbon fiber mixed base material into the vacuum box for vacuuming. After the vacuuming is completed, install the glue storage barrel into the automatic dispensing machine. On the dispensing machine, the mixed base material is extruded through the automatic dispensing machine and arranged in the fixed mold, and then the fixed mold and the carbon fiber mixed base material extruded by the dispensing machine are put into the oven for curing at 150°C. After completion, the thermally conductive silicone embryo body is prepared;

S3. Cut the thermally conductive silicone body into a thickness of 0.1mm through wire cutting equipment to prepare the thermally conductive layer 1. The cutting direction is perpendicular to the extrusion direction of the thermally conductive silicone;

S4. According to the ratio in Table 2, add aluminum powder, zinc oxide, coupling agent, phase change materials and antioxidants into the internal mixer, mix them evenly at 120°C for 30 minutes, and obtain the phase change composite material. The phase change composite material is put into the calender and rolled at 100°C at a speed of 50mm/min to obtain a thermally conductive phase change layer 2 with a thickness of 50μm;

S5. Use a silica gel treatment agent to treat the surface of the thermal conductive layer, and then combine the thermal conductive layer 1 and the thermal conductive phase change layer 2 through hot pressing to form a sandwich structure to prepare a carbon fiber thermal conductive phase change composite material.

In the thermal conductive layer 1, the thermal conductive powder is alumina, the coupling agent is vinyl triethoxysilane, and the curing agent is hydrogen-containing silicone oil; the diameter of the carbon fiber used is 5 to 10 μm, and the length of the carbon fiber is 50 to 150 μm; the thermal conductive powder The average particle size of the body is 1 to 5 μm.

In the thermally conductive phase change layer 2, the coupling agent is dodecyltrimethoxysilane and the antioxidant is 2,6- Tertiary butyl-4-methylphenol, phase change material is paraffin.

Table 1: Ratio of raw materials for the thermal conductive layer in Examples 1-5 (unit: g)

Table 2: Ratio of raw materials for the thermal conductive phase change layer in Examples 1-5 (unit: g)

Example 6

The difference between a carbon fiber thermally conductive phase change composite material and Embodiment 5 is that the diameter of the carbon fiber is 15-20 μm and the length is 250-300 μm.

Example 7

The difference between a carbon fiber thermally conductive phase change composite material and Example 5 is that the added amount of carbon fiber is 250g, the added amount of thermally conductive powder is 1000g, and the rest are consistent with Example 5.

Example 8

The difference between a carbon fiber thermally conductive phase change composite material and Example 7 is that the diameter of the carbon fiber is 10-15 μm, the particle size of the thermally conductive powder is 8-12 μm, and the rest are consistent with Example 7.

Example 9

A carbon fiber thermally conductive phase change composite material. The difference from Embodiment 5 is that the thermally conductive powder is graphite flakes, and the rest are consistent with Embodiment 5.

Example 10

A carbon fiber thermally conductive phase change composite material. The difference from Example 5 is that the thermally conductive powder is a mixture of aluminum oxide, zinc oxide and aluminum nitride. The mass ratio of the three is 1:1:1. The rest are the same as in Example 5. 5. Be consistent.

Example 11

A carbon fiber thermally conductive phase change composite material is different from Example 5 in that the phase change material is a mixture of paraffin wax and silicone wax, and the mass ratio of the two is 1:1. The rest are consistent with Example 5.

Example 12

The difference between a carbon fiber thermally conductive phase change composite material and Example 5 is that the thickness of the thermally conductive layer is 500 μm, and the thickness of the thermally conductive phase change layer is 200 μm. The rest are consistent with Example 5.

Example 13

The difference between a carbon fiber thermally conductive phase change composite material and Example 5 is that the thickness of the thermally conductive layer is 250 μm, and the thickness of the thermally conductive phase change layer is 100 μm. The rest are consistent with Example 5.

Example 14

A thermally conductive phase change composite material, which is different from Example 5 in that it is prepared by the following method:

S1. Add carbon fiber, thermally conductive powder, silicone oil, coupling agent, curing agent and inhibitor and homogenize Mix evenly in the machine, then add the catalyst and continue mixing evenly to obtain the carbon fiber mixed base material;

S2. Add the carbon fiber mixed base material to the glue storage barrel of the automatic dispensing machine. Put the glue storage barrel and the carbon fiber mixed base material into the vacuum box for vacuuming. After the vacuuming is completed, install the glue storage barrel into the automatic dispensing machine. On the dispensing machine, the mixed base material is extruded through the automatic dispensing machine and arranged in the fixed mold, and then the fixed mold and the carbon fiber mixed base material extruded by the dispensing machine are put into the oven for curing at 120°C. After completion, the thermally conductive silicone embryo body is prepared;

S3. Cut the thermally conductive silicone body into a thickness of 0.1mm through wire cutting equipment, and the cutting direction is perpendicular to the extrusion direction of the thermally conductive silicone;

S4. Add aluminum powder, zinc oxide, coupling agent, phase change materials and antioxidants into the internal mixer, mix them evenly at 100°C for 60 minutes to obtain the phase change composite material, and put the phase change composite material into the calender. , a thermally conductive phase change layer with a thickness of 50 μm was produced by rolling at 120°C at a speed of 100㎜/min;

S5. Use a silica gel treatment agent to treat the surface of the thermally conductive layer, and then combine the thermally conductive layer and the thermally conductive phase change layer through hot pressing to form a sandwich structure to prepare a carbon fiber thermally conductive phase change composite material.

The rest are consistent with Example 5.

Comparative ratio

Comparative example 1

A carbon fiber thermally conductive material is provided. The difference from Embodiment 1 is that the thermally conductive phase change layer is not provided, and the rest are consistent with Embodiment 1.

Comparative example 2

A carbon fiber thermally conductive material is provided. The difference from Example 1 is that when preparing the thermally conductive layer, the carbon fiber mixed base material is rolled by calendering to obtain a thermally conductive layer with a specified thickness. All are consistent with Example 1.

Comparative example 3

A carbon fiber thermally conductive material is provided. The difference from Embodiment 1 is that no thermally conductive fiber is added to the phase change layer, and the rest is consistent with Embodiment 1.

Comparative example 4

A carbon fiber thermally conductive material is provided. The difference from Example 1 is that no thermally conductive powder is added to the phase change layer, and the rest are consistent with Example 1.

Performance testing test

Perform performance testing on the samples prepared in Examples 1-14 and Comparative Examples 1-4. The testing standards are as follows:

Thermal conductivity: test the thermal resistance of the sample according to ASTM-D 5470 standard;

Phase change temperature: The phase change temperature of the sample tested according to ASTM-D3418 standard;

Mechanical properties: Test the tensile strength of the sample according to ASTM-D 412 standard;

Flame retardancy: The flame retardant properties of the samples were tested according to the UL-94 standard.

The performance test results are shown in Table 3 below.

Table 3: Performance test results of Examples 1-14 and Comparative Examples 1-4

It can be seen from the data in Table 3 that the carbon fiber thermally conductive phase change composite material provided by the technical solution of this application can effectively reduce the thermal resistance of the product by arranging thermally conductive phase change layers on both sides of the thermally conductive layer and provide better heat conduction efficiency and good mechanical properties. By adjusting the raw material ratio of the thermal conductive layer and the thermal conductive phase change layer, the overall performance of the carbon fiber thermal conductive phase change composite material can be further improved.

It can be seen from the data in Table 3 that compared to directly calendering the carbon fiber mixed base material to prepare the thermal conductive layer, the thermal conductive layer material prepared by the preparation method provided by the technical solution of this application has better thermal conductivity effect and can be more fully utilized. Anisotropic thermal conductivity properties of carbon fiber. Moreover, the directional arrangement method of carbon fibers in this method is simple and effective, has extremely low cost, and has high production efficiency.

The above are all preferred embodiments of the present application and do not limit the scope of protection of the present application. Therefore: All equivalent changes based on the structure, shape, and principle of this application shall be covered by the protection scope of this application.

Claims

A carbon fiber thermally conductive phase change composite material, characterized by: including a thermally conductive layer and thermally conductive phase change layers arranged on both sides of the thermally conductive layer;

The thermal conductive layer includes the following raw materials by weight: 100 to 700 parts of carbon fiber, 150 to 1700 parts of thermally conductive powder, 50 to 120 parts of silicone oil, 0.3 to 2 parts of coupling agent, 1 to 4 parts of curing agent, and 0.1 to 0.1 part of inhibitor. 1 part, 1 to 4 parts of catalyst;

The thermally conductive phase change layer includes the following raw materials by weight: 170 to 190 parts of aluminum powder, 2 to 20 parts of zinc oxide, 1 to 8 parts of coupling agent, 2 to 10 parts of phase change material, and 2 to 5 parts of antioxidants;

The thermally conductive phase change layer is located on both sides of the thermally conductive layer perpendicular to the axial direction of the thermally conductive fiber.
The carbon fiber thermally conductive phase change composite material according to claim 1, characterized in that the diameter of the carbon fiber is 5-20 μm and the length is 50-300 μm.
The carbon fiber thermally conductive phase change composite material according to claim 1, characterized in that: the thermally conductive powder is aluminum oxide, zinc oxide, magnesium oxide, aluminum nitride, graphite sheets, graphene, aluminum powder, copper powder and silver At least one type of aluminum powder is included; the average particle size of the thermally conductive powder is 1 to 15 μm.
The carbon fiber thermally conductive phase change composite material according to claim 1, characterized in that: the phase change material is paraffin wax, micro wax, silicone wax, polybutadiene, polyisoprene and hydroxyl-terminated polyisoprene. At least one kind of alkenes.
The carbon fiber thermally conductive phase change composite material according to claim 1, characterized in that: the thickness of the thermally conductive layer 1 is 100-500 μm, and the thickness of the thermally conductive phase-change layer 2 is 50-200μm.
The preparation method of carbon fiber thermally conductive phase change composite material according to any one of claims 1 to 5, characterized in that it includes the following steps:

Prepare the carbon fiber mixed base material: Mix the carbon fiber, thermally conductive powder, silicone oil, coupling agent, curing agent and inhibitor evenly, then add the catalyst and continue mixing to obtain the carbon fiber mixed base material;

Preparing the carbon fiber thermally conductive embryonic body: vacuuming the carbon fiber mixed base material. After the vacuuming process, the carbon fiber mixed base material is extruded through an automatic dispensing machine and arranged in the mold. After solidification, the thermally conductive silicone embryonic body is obtained;

Preparing the thermally conductive layer: Cut the thermally conductive silicone embryo into a specified thickness to obtain the thermally conductive layer. The cutting direction is perpendicular to the extrusion direction of the thermally conductive silicone embryo;

Preparing the thermally conductive phase change layer: Mix aluminum powder, zinc oxide, coupling agent, phase change material and antioxidant evenly to obtain a phase change material, and roll the phase change material to a specified thickness to obtain a phase change layer;

Preparation of carbon fiber thermally conductive phase change composite materials: Use a silica gel treatment agent to treat the surface of the thermally conductive layer, and then hot-press composite the thermally conductive layer and the thermally conductive phase change layer to prepare a carbon fiber thermally conductive phase change composite material.
The method for preparing carbon fiber thermally conductive phase change composite materials according to claim 6, characterized in that: in the step of preparing phase change materials, the raw materials are mixed evenly in an internal mixer, the internal mixing temperature is 100-130°C, and the internal mixing time The rolling temperature is 0.5~1h; the rolling temperature is 80~120℃, and the rolling speed is 50~100mm/min.
The method for preparing carbon fiber thermally conductive phase change composite materials according to claim 6, characterized in that: in the step of preparing carbon fiber thermally conductive phase change composite materials, the hot pressing temperature is 90-110°C, and the hot-pressing time is 3-5 minutes.