Gradient heat conduction wood fiber composite wallboard and preparation method thereof

Abstract

The invention discloses a gradient heat conduction wood fiber composite wallboard and a preparation method thereof, and belongs to the technical field of composite wallboard preparation.According to the gradient heat conduction wood fiber composite wallboard and the preparation method thereof, wood fibers and reinforced fibers are smashed and mixed and then poured into an adhesive, the wood fibers and the reinforced fibers are bonded through the adhesive, and the gradient heat conduction wood fiber composite wallboard is obtained; the preparation method comprises the following steps: mixing and adhering wood fibers and reinforced fibers, pouring the mixed and adhered wood fibers and reinforced fibers into a mold, pressurizing and drying to prepare a base material layer of the gradient heat-conducting wood fiber composite wallboard, so that the base material layer has better crack resistance and mechanical strength, and mixing a paraffin-based phase change material and expanded graphite according to a certain proportion to prepare the gradient heat-conducting wood fiber composite wallboard. The paraffin-based phase-change material fully utilizes the embedded space structure of the expanded graphite with large and small particle sizes, so that the thermal diffusion coefficient after the paraffin-based phase-change material and the expanded graphite are mixed is improved, the heat conduction enhancement layer has the best performance in the aspects of heat transfer efficiency, heat stability, heat storage efficiency and the like, and the heat conduction efficiency of the wallboard is improved.

Description

Technical Field

[0001] This invention belongs to the field of composite wall panel preparation technology, specifically a gradient thermally conductive wood fiber composite wall panel and its preparation method. Background Technology

[0002] Composite wall panels, as a new type of building wall material, combine multiple materials with different properties to fully leverage the advantages of each material and compensate for the shortcomings of a single material, thereby achieving a comprehensive improvement in wall performance. This meets the comprehensive performance requirements of modern buildings in terms of thermal insulation, fireproofing, waterproofing, sound insulation, high strength, lightweighting, and environmental friendliness. Among them, wood fiber, as a renewable resource, has significant advantages such as wide availability, relatively low cost, and environmental friendliness. Its unique fiber structure endows the material with good mechanical strength and toughness. After wood fiber is made into composite wall panels, the composite wall panels can effectively resist external impacts and pressures, extending the service life of the wall panels.

[0003] Existing pure wood fiber composite wall panels have certain limitations in terms of thermal conductivity and fire resistance, making it difficult to meet the high-performance requirements of modern buildings for wall materials. They are prone to problems such as local heat accumulation and uneven heat conduction, which affect the thermal stability of the wall. Therefore, improvements are needed. Summary of the Invention

[0004] To overcome the above-mentioned defects, the present invention provides a gradient thermally conductive wood fiber composite wall panel and its preparation method, which solves the problem that existing pure wood fiber composite wall panels have certain limitations in terms of thermal conductivity and fire resistance, making it difficult to meet the high-performance requirements of modern buildings for wall materials, and easily causing local heat accumulation and uneven thermal conductivity.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a gradient thermally conductive wood fiber composite wall panel, comprising a substrate layer, a thermally conductive reinforcing layer on one side of the substrate layer, and a protective layer on the side of the thermally conductive reinforcing layer away from the substrate layer.

[0006] As a further aspect of the present invention: the substrate layer is made by mixing 30-70 parts of wood fiber, 10-20 parts of reinforcing fiber, 50 parts of adhesive and 100 parts of water.

[0007] As a further aspect of the present invention: the thermally conductive enhancement layer is composed of 40-80 parts of paraffin-based phase change material and 10-20 parts of expanded graphite, and a thermally conductive pipe network is embedded inside the thermally conductive enhancement layer. The thermally conductive pipe network is a hollow copper mesh structure and is connected to the circulation pipeline of the air source heat pump system.

[0008] As a further embodiment of the present invention: the protective layer is formed by spraying a mixture of 5-10 parts of nano-silica hydrophobic coating, 10-30 parts of acrylic resin and 60-100 parts of water.

[0009] A method for preparing a gradient thermally conductive wood fiber composite wall panel, the method comprising the following steps:

[0010] S1: Pour 30-70 parts of wood fiber and 10-20 parts of reinforcing fiber into a pulverizer for pulverization and screening. At the same time, mix 50 parts of adhesive and 100 parts of water. After the wood fiber and reinforcing fiber are pulverized, weigh the wood fiber and reinforcing fiber and pour them into the mixed adhesive and water. After stirring and mixing, pour the wood fiber, reinforcing fiber and adhesive into a mold for pressing and molding. Then dry the molded material. S2: Heat and stir 40-80 parts of paraffin-based phase change material and 10-20 parts of expanded graphite, then pour the mixed material into a mold, and place a heat-conducting pipe network in the material. Apply pressure to the material for a certain period of time to compress and shape it. Finally, cool and solidify the shaped heat-conducting reinforcement layer. S3: Place the dried substrate layer on the lower mold of the hot press, and place the thermally conductive reinforcement layer on top of the substrate layer. Ensure that the surfaces of the substrate layer and the thermally conductive reinforcement layer on opposite sides are clean and free of impurities. Start the hot press and heat press the substrate layer and the thermally conductive reinforcement layer at the set temperature and pressure until they are bonded together. After the heat pressing is completed, control the bonded substrate layer and the thermally conductive reinforcement layer to cool naturally inside the hot press to avoid stress caused by a sudden drop in temperature. S4: While the hot-pressed substrate layer and thermally conductive reinforcement layer are naturally cooling, 5 parts of nano-silica hydrophobic coating, 15 parts of acrylic resin and 80 parts of water are stirred and mixed. After the substrate layer and thermally conductive reinforcement layer have cooled naturally, the mixed protective layer is evenly sprayed onto the surface of the hot-pressed substrate layer and thermally conductive reinforcement layer through a nozzle. Then, the substrate layer and thermally conductive reinforcement layer with the protective layer are placed in an oven for drying, forming a coating on the surface of the substrate layer and thermally conductive reinforcement layer.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0012] In this invention, wood fibers and reinforcing fibers are crushed and mixed, then poured into an adhesive to bond them together. The mixed and bonded wood fibers and reinforcing fibers are then poured into a mold and dried under pressure to create the substrate layer of a gradient thermally conductive wood fiber composite wall panel. This substrate layer has good crack resistance and mechanical strength. At the same time, paraffin-based phase change material and expanded graphite are mixed in a certain proportion. This allows the paraffin-based phase change material to fully utilize the embedded spatial structure of expanded graphite of different particle sizes, improving the thermal diffusivity of the mixture. This results in the thermally conductive reinforcing layer exhibiting optimal performance in terms of heat transfer efficiency, thermal stability, and heat storage efficiency, thereby improving the thermal conductivity of the wall panel. Attached Figure Description

[0013] Figure 1 This is a cross-sectional structural diagram of the present invention;

[0014] In the diagram: 1. Substrate layer; 2. Thermally conductive reinforcement layer; 201. Thermally conductive pipe network; 3. Protective layer. Detailed Implementation

[0015] The technical solution of this application will be further described in detail below with reference to specific embodiments.

[0016] As shown in the figure, the present invention provides a technical solution: a gradient thermally conductive wood fiber composite wall panel, comprising a substrate layer, a thermally conductive reinforcing layer on one side of the substrate layer, and a protective layer on the side of the thermally conductive reinforcing layer away from the substrate layer.

[0017] The substrate layer is made of 30-70 parts wood fiber, 10-20 parts reinforcing fiber, 50 parts adhesive and 100 parts water.

[0018] The thermally conductive reinforcement layer is composed of 40-80 parts of paraffin-based phase change material and 10-20 parts of expanded graphite. A thermally conductive network is embedded inside the thermally conductive reinforcement layer. The thermally conductive network is a hollow copper mesh structure and is connected to the circulation pipeline of the air source heat pump system.

[0019] The protective layer is formed by spraying a mixture of 5-10 parts of nano-silica hydrophobic coating, 10-30 parts of acrylic resin and 60-100 parts of water.

[0020] Example 1:

[0021] A method for preparing a gradient thermally conductive wood fiber composite wall panel, the method comprising the following steps: S1: Pour 30-70 parts of wood fiber and 10-20 parts of reinforcing fiber into a pulverizer for pulverization and screening. At the same time, mix 50 parts of adhesive and 100 parts of water. After the wood fiber and reinforcing fiber are pulverized separately, weigh the wood fiber and reinforcing fiber in a 5:1 ratio and pour them into the mixed adhesive and water. After stirring and mixing, pour the wood fiber, reinforcing fiber and adhesive into a mold for pressing and molding, and then dry the molded material. S2: Heat and stir 40-80 parts of paraffin-based phase change material and 10-20 parts of expanded graphite, then pour the mixed material into a mold, and place a heat-conducting pipe network in the material. Apply pressure to the material for a certain period of time to compress and shape it. Finally, cool and solidify the shaped heat-conducting reinforcement layer. S3: Place the dried substrate layer on the lower mold of the hot press, and place the thermally conductive reinforcement layer on top of the substrate layer. Ensure that the surfaces of the substrate layer and the thermally conductive reinforcement layer on opposite sides are clean and free of impurities. Start the hot press and heat press the substrate layer and the thermally conductive reinforcement layer at the set temperature and pressure until they are bonded together. After the heat pressing is completed, control the bonded substrate layer and the thermally conductive reinforcement layer to cool naturally inside the hot press to avoid stress caused by a sudden drop in temperature. S4: While the hot-pressed substrate layer and thermally conductive reinforcement layer are naturally cooling, 5 parts of nano-silica hydrophobic coating, 15 parts of acrylic resin and 80 parts of water are stirred and mixed. After the substrate layer and thermally conductive reinforcement layer have cooled naturally, the mixed protective layer is evenly sprayed onto the surface of the hot-pressed substrate layer and thermally conductive reinforcement layer through a nozzle. Then, the substrate layer and thermally conductive reinforcement layer with the protective layer are placed in an oven for drying, forming a coating on the surface of the substrate layer and thermally conductive reinforcement layer.

[0022] Example 2:

[0023] A method for preparing a gradient thermally conductive wood fiber composite wall panel, the method comprising the following steps: S1: Pour 30-70 parts of wood fiber and 10-20 parts of reinforcing fiber into a pulverizer for pulverization and screening. At the same time, mix 50 parts of adhesive and 100 parts of water. After the wood fiber and reinforcing fiber are pulverized separately, weigh the wood fiber and reinforcing fiber in a 5:2 ratio and pour them into the mixed adhesive and water. After stirring and mixing, pour the wood fiber, reinforcing fiber and adhesive into a mold for pressing and molding, and then dry the molded material. S2: Heat and stir 40-80 parts of paraffin-based phase change material and 10-20 parts of expanded graphite, then pour the mixed material into a mold, and place a heat-conducting pipe network in the material. Apply pressure to the material for a certain period of time to compress and shape it. Finally, cool and solidify the shaped heat-conducting reinforcement layer. S3: Place the dried substrate layer on the lower mold of the hot press, and place the thermally conductive reinforcement layer on top of the substrate layer. Ensure that the surfaces of the substrate layer and the thermally conductive reinforcement layer on opposite sides are clean and free of impurities. Start the hot press and heat press the substrate layer and the thermally conductive reinforcement layer at the set temperature and pressure until they are bonded together. After the heat pressing is completed, control the bonded substrate layer and the thermally conductive reinforcement layer to cool naturally inside the hot press to avoid stress caused by a sudden drop in temperature. S4: While the hot-pressed substrate layer and thermally conductive reinforcement layer are naturally cooling, 5 parts of nano-silica hydrophobic coating, 15 parts of acrylic resin and 80 parts of water are stirred and mixed. After the substrate layer and thermally conductive reinforcement layer have cooled naturally, the mixed protective layer is evenly sprayed onto the surface of the hot-pressed substrate layer and thermally conductive reinforcement layer through a nozzle. Then, the substrate layer and thermally conductive reinforcement layer with the protective layer are placed in an oven for drying, forming a coating on the surface of the substrate layer and thermally conductive reinforcement layer.

[0024] Example 3:

[0025] A method for preparing a gradient thermally conductive wood fiber composite wall panel, the method comprising the following steps: S1: Pour 30-70 parts of wood fiber and 10-20 parts of reinforcing fiber into a pulverizer for pulverization and screening. At the same time, mix 50 parts of adhesive and 100 parts of water. After the wood fiber and reinforcing fiber are pulverized separately, weigh the wood fiber and reinforcing fiber in a 5:3 ratio and pour them into the mixed adhesive and water. After stirring and mixing, pour the wood fiber, reinforcing fiber and adhesive into a mold for pressing and molding, and then dry the molded material. S2: Heat and stir 40-80 parts of paraffin-based phase change material and 10-20 parts of expanded graphite, then pour the mixed material into a mold, and place a heat-conducting pipe network in the material. Apply pressure to the material for a certain period of time to compress and shape it. Finally, cool and solidify the shaped heat-conducting reinforcement layer. S3: Place the dried substrate layer on the lower mold of the hot press, and place the thermally conductive reinforcement layer on top of the substrate layer. Ensure that the surfaces of the substrate layer and the thermally conductive reinforcement layer on opposite sides are clean and free of impurities. Start the hot press and heat press the substrate layer and the thermally conductive reinforcement layer at the set temperature and pressure until they are bonded together. After the heat pressing is completed, control the bonded substrate layer and the thermally conductive reinforcement layer to cool naturally inside the hot press to avoid stress caused by a sudden drop in temperature. S4: While the hot-pressed substrate layer and thermally conductive reinforcement layer are naturally cooling, 5 parts of nano-silica hydrophobic coating, 15 parts of acrylic resin and 80 parts of water are stirred and mixed. After the substrate layer and thermally conductive reinforcement layer have cooled naturally, the mixed protective layer is evenly sprayed onto the surface of the hot-pressed substrate layer and thermally conductive reinforcement layer through a nozzle. Then, the substrate layer and thermally conductive reinforcement layer with the protective layer are placed in an oven for drying, forming a coating on the surface of the substrate layer and thermally conductive reinforcement layer.

[0026] The following table is derived from Examples 1-3: Wood fiber: reinforcing fiber Tensile strength (MPa) Compressive strength (MPa) Example 1 5∶1 26.3 69.2 Example 2 5∶2 38.7 65.8 Example 3 5∶3 41.5 52.6

[0027] As can be seen from the comparison in the table above, when wood fiber and reinforcing fiber are mixed in a ratio of 5:2, the overall performance of substrate layer 1 is more balanced, with both good crack resistance and mechanical strength.

[0028] Example 4:

[0029] A method for preparing a gradient thermally conductive wood fiber composite wall panel, the method comprising the following steps: S1: Pour 30-70 parts of wood fiber and 10-20 parts of reinforcing fiber into a pulverizer for pulverization and screening. At the same time, mix 50 parts of adhesive and 100 parts of water. After the wood fiber and reinforcing fiber are pulverized separately, weigh the wood fiber and reinforcing fiber in a 5:2 ratio and pour them into the mixed adhesive and water. After stirring and mixing, pour the wood fiber, reinforcing fiber and adhesive into a mold for pressing and molding, and then dry the molded material. S2: Heat and stir 40-80 parts of paraffin-based phase change material and 10-20 parts of expanded graphite in a ratio of 8:1, then pour the mixed material into a mold, place a heat-conducting pipe network in the material, apply pressure to the material for a certain period of time to compress and shape it, and finally cool and solidify the shaped heat-conducting reinforcement layer. S3: Place the dried substrate layer on the lower mold of the hot press, and place the thermally conductive reinforcement layer on top of the substrate layer. Ensure that the surfaces of the substrate layer and the thermally conductive reinforcement layer on opposite sides are clean and free of impurities. Start the hot press and heat press the substrate layer and the thermally conductive reinforcement layer at the set temperature and pressure until they are bonded together. After the heat pressing is completed, control the bonded substrate layer and the thermally conductive reinforcement layer to cool naturally inside the hot press to avoid stress caused by a sudden drop in temperature. S4: While the hot-pressed substrate layer and thermally conductive reinforcement layer are naturally cooling, 5 parts of nano-silica hydrophobic coating, 15 parts of acrylic resin and 80 parts of water are stirred and mixed. After the substrate layer and thermally conductive reinforcement layer have cooled naturally, the mixed protective layer is evenly sprayed onto the surface of the hot-pressed substrate layer and thermally conductive reinforcement layer through a nozzle. Then, the substrate layer and thermally conductive reinforcement layer with the protective layer are placed in an oven for drying, forming a coating on the surface of the substrate layer and thermally conductive reinforcement layer.

[0030] Example 5:

[0031] A method for preparing a gradient thermally conductive wood fiber composite wall panel, the method comprising the following steps:

[0032] S1: Pour 30-70 parts of wood fiber and 10-20 parts of reinforcing fiber into a pulverizer for pulverization and screening. At the same time, mix 50 parts of adhesive and 100 parts of water. After the wood fiber and reinforcing fiber are pulverized separately, weigh the wood fiber and reinforcing fiber in a 5:2 ratio and pour them into the mixed adhesive and water. After stirring and mixing, pour the wood fiber, reinforcing fiber and adhesive into a mold for pressing and molding, and then dry the molded material.

[0033] S2: Heat and stir 40-80 parts of paraffin-based phase change material and 10-20 parts of expanded graphite in a ratio of 9:1, then pour the mixed material into a mold, place a heat-conducting pipe network in the material, apply pressure to the material for a certain period of time to compress and shape it, and finally cool and solidify the shaped heat-conducting reinforcement layer.

[0034] S3: Place the dried substrate layer on the lower mold of the hot press, and place the thermally conductive reinforcement layer on top of the substrate layer. Ensure that the surfaces of the substrate layer and the thermally conductive reinforcement layer on opposite sides are clean and free of impurities. Start the hot press and heat press the substrate layer and the thermally conductive reinforcement layer at the set temperature and pressure until they are bonded together. After the heat pressing is completed, control the bonded substrate layer and the thermally conductive reinforcement layer to cool naturally inside the hot press to avoid stress caused by a sudden drop in temperature.

[0035] S4: While the hot-pressed substrate layer and thermally conductive reinforcement layer are naturally cooling, 5 parts of nano-silica hydrophobic coating, 15 parts of acrylic resin and 80 parts of water are stirred and mixed. After the substrate layer and thermally conductive reinforcement layer have cooled naturally, the mixed protective layer is evenly sprayed onto the surface of the hot-pressed substrate layer and thermally conductive reinforcement layer through a nozzle. Then, the substrate layer and thermally conductive reinforcement layer with the protective layer are placed in an oven for drying, forming a coating on the surface of the substrate layer and thermally conductive reinforcement layer.

[0036] Example 6:

[0037] A method for preparing a gradient thermally conductive wood fiber composite wall panel, the method comprising the following steps:

[0038] S1: Pour 30-70 parts of wood fiber and 10-20 parts of reinforcing fiber into a pulverizer for pulverization and screening. At the same time, mix 50 parts of adhesive and 100 parts of water. After the wood fiber and reinforcing fiber are pulverized separately, weigh the wood fiber and reinforcing fiber in a 5:2 ratio and pour them into the mixed adhesive and water. After stirring and mixing, pour the wood fiber, reinforcing fiber and adhesive into a mold for pressing and molding, and then dry the molded material.

[0039] S2: Heat and stir 40-80 parts of paraffin-based phase change material and 10-20 parts of expanded graphite in a ratio of 10:1, then pour the mixed material into a mold, place a heat-conducting pipe network in the material, apply pressure to the material for a certain period of time to compress and shape it, and finally cool and solidify the shaped heat-conducting reinforcement layer.

[0040] S3: Place the dried substrate layer on the lower mold of the hot press, and place the thermally conductive reinforcement layer on top of the substrate layer. Ensure that the surfaces of the substrate layer and the thermally conductive reinforcement layer on opposite sides are clean and free of impurities. Start the hot press and heat press the substrate layer and the thermally conductive reinforcement layer at the set temperature and pressure until they are bonded together. After the heat pressing is completed, control the bonded substrate layer and the thermally conductive reinforcement layer to cool naturally inside the hot press to avoid stress caused by a sudden drop in temperature.

[0041] S4: While the hot-pressed substrate layer and thermally conductive reinforcement layer are naturally cooling, 5 parts of nano-silica hydrophobic coating, 15 parts of acrylic resin and 80 parts of water are stirred and mixed. After the substrate layer and thermally conductive reinforcement layer have cooled naturally, the mixed protective layer is evenly sprayed onto the surface of the hot-pressed substrate layer and thermally conductive reinforcement layer through a nozzle. Then, the substrate layer and thermally conductive reinforcement layer with the protective layer are placed in an oven for drying, forming a coating on the surface of the substrate layer and thermally conductive reinforcement layer.

[0042] The following table is derived from Examples 4-6:

[0043] The comparison in the table above shows that when paraffin-based phase change materials and expanded graphite are mixed in a 9:1 ratio, the mixed material has the largest thermal diffusivity and performs best in terms of heat transfer efficiency, thermal stability, and heat storage efficiency.

[0044] In the description of this invention, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0045] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0046] Finally, it should be noted that although the present invention has been described in detail above with general descriptions and specific embodiments, the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A gradient thermally conductive wood fiber composite wall panel, comprising a substrate layer (1), characterized in that: A thermally conductive reinforcing layer (2) is provided on one side of the substrate layer (1), and a protective layer (3) is provided on the side of the thermally conductive reinforcing layer (2) away from the substrate layer (1).

2. The gradient thermally conductive wood fiber composite wall panel according to claim 1, characterized in that: The substrate layer (1) is made of 30-70 parts of wood fiber, 10-20 parts of reinforcing fiber, 50 parts of adhesive and 100 parts of water.

3. The gradient thermally conductive wood fiber composite wall panel according to claim 1, characterized in that: The thermally conductive enhancement layer (2) is composed of 40-80 parts of paraffin-based phase change material and 10-20 parts of expanded graphite. A thermally conductive pipe network (201) is embedded inside the thermally conductive enhancement layer (2). The thermally conductive pipe network (201) is a hollow copper mesh structure and is connected to the circulation pipeline of the air source heat pump system.

4. The gradient thermally conductive wood fiber composite wall panel according to claim 1, characterized in that: The protective layer (3) is formed by spraying a mixture of 5-10 parts of nano-silica hydrophobic coating, 10-30 parts of acrylic resin and 60-100 parts of water.

5. A method for preparing a gradient thermally conductive wood fiber composite wall panel, wherein the gradient thermally conductive wood fiber composite wall panel according to any one of claims 1-4 is characterized in that: The preparation method includes the following steps: S1: Pour 30-70 parts of wood fiber and 10-20 parts of reinforcing fiber into a pulverizer for pulverization and screening. At the same time, mix 50 parts of adhesive and 100 parts of water. After the wood fiber and reinforcing fiber are pulverized, weigh the wood fiber and reinforcing fiber and pour them into the mixed adhesive and water. After stirring and mixing, pour the wood fiber, reinforcing fiber and adhesive into a mold for pressing and molding. Then dry the molded material. S2: After heating and stirring 40-80 parts of paraffin-based phase change material and 10-20 parts of expanded graphite, pour the mixed material into a mold, and at the same time put a heat-conducting pipe network (201) into the material, apply pressure to the material for a certain period of time to compress and shape it, and finally cool and solidify the shaped heat-conducting reinforcement layer (2). S3: Place the dried substrate layer (1) in the lower mold of the hot press, and place the thermally conductive reinforcing layer (2) on top of the substrate layer (1) to ensure that the surfaces of the substrate layer (1) and the thermally conductive reinforcing layer (2) are clean and free of impurities. Start the hot press and heat press the substrate layer (1) and the thermally conductive reinforcing layer (2) at the set temperature and pressure until the substrate layer (1) and the thermally conductive reinforcing layer (2) are bonded together. After the heat pressing is completed, control the bonded substrate layer (1) and the thermally conductive reinforcing layer (2) to cool naturally inside the hot press to avoid stress generated inside the substrate layer (1) and the thermally conductive reinforcing layer (2) due to a sudden drop in temperature. S4: When the substrate layer (1) and thermally conductive reinforcing layer (2) after hot pressing are naturally cooled, 5 parts of nano-silica hydrophobic coating, 15 parts of acrylic resin and 80 parts of water are stirred and mixed. After the substrate layer (1) and thermally conductive reinforcing layer (2) are naturally cooled, the mixed protective layer (3) is evenly sprayed onto the surface of the substrate layer (1) and thermally conductive reinforcing layer (2) after hot pressing. Then the substrate layer (1) and thermally conductive reinforcing layer (2) with the protective layer (3) are placed in the oven for drying, and a coating is formed on the surface of the substrate layer (1) and thermally conductive reinforcing layer (2).

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