Coatable double-sided high-thermal-conductivity silica gel film and preparation method thereof

Abstract

This application discloses a coatable double-sided high thermal conductivity silicone film and its preparation method. The preparation method involves formulating a silicone matrix, mixed thermally conductive fillers, and additives into an adhesive liquid with a specific viscosity and curing amount to ensure excellent leveling properties during coating. The adhesive liquid is first coated onto the surface of a release film and pre-cured at a low temperature of 50-80°C to a semi-solid state, giving the adhesive layer sufficient cohesive strength to maintain a smooth film surface while retaining tackiness for pressing. Utilizing the semi-cured state of the adhesive film, a pressing roller directly transfers the adhesive layer from the release film to both sides of a fiberglass mesh. Finally, high-temperature step curing achieves complete cross-linking. This fundamentally solves the problem that high-viscosity thermally conductive silicone cannot be directly coated onto wide-width fiberglass mesh, and eliminates the need for pre-coating the fiberglass cloth. The resulting film has a smooth and flat surface with uniform thickness, and allows for continuous winding production, overcoming the limitations of traditional spraying and brushing methods that only produce sheet-like outputs.

Description

Technical Field

[0001] This application relates to the field of thin film technology, and in particular to a coatable double-sided high thermal conductivity silicone film and its preparation method. Background Technology

[0002] As electronic devices continue to evolve towards miniaturization and high performance, heat dissipation becomes an increasingly prominent issue. Thermally conductive adhesive films, as an important heat dissipation material, have been widely used in electronic devices. However, traditional thermally conductive adhesive films suffer from insufficient thermal conductivity, poor flexibility, and weak adhesion to the substrate, making it difficult to meet the demands of modern electronic devices for efficient heat dissipation.

[0003] Common silicone substrates inherently have low thermal conductivity, and even with the addition of large amounts of thermally conductive fillers, it is still difficult to achieve high overall thermal conductivity. Furthermore, high filler content often leads to a significant decrease in the film's flexibility, making it prone to cracking during actual use, thus affecting its lifespan and heat dissipation performance. Meanwhile, currently available thermally conductive silicone films are mainly manufactured using spraying or brushing methods, requiring a primer coating on the fiberglass mesh. However, this process suffers from low production efficiency, uneven thickness, rough surface, and difficulty in achieving large-width continuous production. The high-temperature curing temperature reaches 160℃~170℃, resulting in high energy consumption. Summary of the Invention

[0004] This application provides a coatable double-sided high thermal conductivity silicone film and its preparation method to solve the technical problems of traditional thermally conductive adhesive films being unable to be directly coated with mesh fiberglass cloth, having poor film flexibility, and low production efficiency.

[0005] In a first aspect, this application provides a method for preparing a coatable double-sided high thermal conductivity silicone film, comprising the following steps: S1. Mix the silicone matrix, thermally conductive filler and additives evenly and degas under vacuum. Add solvent to adjust the viscosity to 3000 mPa·s ~ 7000 mPa·s and control the curing amount of the adhesive liquid to 80%~95% to obtain thermally conductive silicone liquid. S2, the thermally conductive silicone liquid is applied to the release surface of the first release film by a scraping method, and a semi-cured first thermally conductive silicone layer is formed by low-temperature pre-curing. Then, the first thermally conductive silicone layer is transferred to the first surface of the fiberglass mesh cloth by a pressing roller. S3, the thermally conductive silicone liquid is coated onto the release surface of the second release film by a scraping method, and a semi-cured second thermally conductive silicone layer is formed by low-temperature pre-curing. Then, the second thermally conductive silicone layer is transferred to the second surface of the fiberglass mesh obtained in S2 by a pressing roller to obtain a composite adhesive film. S4. The composite film is cured at high temperature and then wound up to obtain a coatable double-sided high thermal conductivity film.

[0006] In some of these embodiments, the silicone matrix comprises vinyl-terminated polydimethylsiloxane, which releases no small molecule byproducts during the vulcanization crosslinking process and has an extremely low volume shrinkage rate, ensuring that the film is free of bubbles and has a smooth surface after curing. The thermally conductive filler includes at least two of the following: metal filler, metal oxide filler, and non-metal filler. The metal filler includes at least one of silver powder, aluminum powder, and copper powder. The metal oxide includes at least one of aluminum oxide and zinc oxide. The non-metal filler includes at least one of boron nitride, silicon carbide, and graphene. By using a blend of at least two materials with different morphologies or particle sizes, a more efficient thermally conductive pathway network can be constructed, overcoming the bottleneck of limited filling amount of a single filler and significantly improving the thermal conductivity while ensuring the flexibility of the adhesive film. The additives include dispersants, vulcanizing agents, and plasticizers; the dispersant can be a silane coupling agent such as KH550, KH560, or KH570, used to improve the compatibility between the filler and the silicone and reduce agglomeration, and the dosage is 1% to 3% of the filler mass; the vulcanizing agent can be a platinum catalyst, used to control the crosslinking reaction of addition-type silicone, and the dosage is 0.5% to 2% of the silicone matrix mass; the plasticizer can be dimethyl silicone oil, used to adjust the hardness and flexibility of the film, and the dosage is 5% to 15% of the silicone matrix mass.

[0007] In some of these embodiments, in S2 and S3, low-temperature pre-curing is performed in a first multi-gradient oven at a temperature of 50°C to 80°C; and in S4, high-temperature curing is performed in a second multi-gradient oven at a temperature of 100°C to 130°C.

[0008] The low-temperature stage only allows the adhesive to evaporate solvent and reach a semi-solid state, which both fixes the coating shape for easy peeling and transfer and prevents excessive cross-linking that could lead to loss of adhesion under pressure. The high-temperature stage achieves deep cross-linking of the silicone matrix, giving the adhesive film its final mechanical strength and electrical insulation properties. Compared to the traditional single-stage high-temperature curing at 160℃~170℃, this embodiment effectively reduces energy consumption through a segmented temperature control strategy and avoids potential thermal damage to the release film substrate from high temperatures, ensuring production stability.

[0009] In some of these embodiments, the gradient temperatures of the first multi-gradient oven are 50°C, 60°C, 70°C, 80°C, 80°C and 70°C, respectively. The gradient temperatures of the second multi-gradient oven are 100℃, 120℃, 130℃, 130℃, 130℃ and 120℃.

[0010] The pre-curing stage employs a peak temperature control method, gradually increasing from 50℃ to 80℃ and then decreasing back to 70℃. This allows the solvent in the adhesive to slowly evaporate from the surface inwards, preventing the surface from forming a skin that encapsulates internal air bubbles. The high-temperature curing stage, with its gradual temperature increase from 100℃ to 130℃, ensures a smooth cross-linking reaction, avoiding internal stress shrinkage caused by uneven cross-linking density due to sudden high temperatures. This embodiment, through precise temperature control, ensures that the finished adhesive film does not warp or crack during winding and die-cutting, significantly improving product yield and surface smoothness.

[0011] In some embodiments, the pressing pressure of the pressing roller in steps S2 and S3 is 0.2 MPa to 0.4 MPa.

[0012] In some embodiments, the maximum coating width of the scraping method is 1260 mm. Wide-width coating greatly increases single-batch production capacity, enabling continuous mass production of thermally conductive silicone films; compared to narrow-width slitting and lamination, it reduces waste of scrap material and seam joints; at the same time, because it is first scraped and formed on a high-flatness release film before being transferred, it avoids knife marks and thickness fluctuations caused by scraping directly on rough fiberglass cloth.

[0013] In some embodiments, the solvent is methyl ethyl ketone (MEK). During the initial pre-curing stage, MEK can rapidly and smoothly diffuse from the interior of the adhesive layer to the surface for evaporation, without causing skinning or pinhole defects on the adhesive film surface due to excessively rapid evaporation, nor leaving bubbles in the cured film due to excessively slow evaporation.

[0014] In some embodiments, the coating thickness of the first thermally conductive silicone layer is 0.1 mm to 0.3 mm.

[0015] In some embodiments, both the first and second release films are coated with a non-silicone release agent, the release force of which is 20g~40g. This ensures stable production conveyor belt operation while allowing for easy peeling during use, exposing a smooth and flat adhesive film surface for downstream bonding and assembly.

[0016] Secondly, this application also provides a coatable double-sided high thermal conductivity silicone film, comprising a first release film layer, a first thermally conductive silicone layer, a fiberglass mesh layer, a second thermally conductive silicone layer, and a first release film layer stacked sequentially.

[0017] Compared with the prior art, this application has the following beneficial effects: A silicone matrix, mixed thermally conductive fillers, and additives are formulated into an adhesive solution with a specific viscosity and curing amount to ensure excellent leveling properties during scraping. The adhesive solution is first scraped onto the surface of a release film and pre-cured at a low temperature of 50-80℃ to a semi-solid state. This ensures the adhesive layer has sufficient cohesive strength to maintain a smooth film surface while retaining tackiness for pressing. Utilizing the semi-cured state of the adhesive film, a pressing roller directly transfers the adhesive layer from the release film to both sides of the fiberglass mesh. Finally, a high-temperature stepped curing process achieves complete cross-linking. This method fundamentally solves the industry problem of high-viscosity thermally conductive silicone being unable to be directly scraped onto wide-width fiberglass mesh, eliminating the need for pre-coating the fiberglass cloth. The resulting adhesive film has a smooth, flat surface, uniform thickness, and significantly improved production efficiency. Furthermore, this method enables continuous winding production, overcoming the limitations of traditional spraying and brushing methods that only produce sheet-like outputs. Detailed Implementation

[0018] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described in detail below. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0019] As used herein, the terms “prepared from” and “comprising” are synonymous. The terms “comprising,” “including,” “having,” “containing,” or any other variations thereof, as used herein, are intended to cover non-exclusive inclusion. For example, a composition, step, method, article, or apparatus that includes the listed elements is not necessarily limited to those elements, but may include other elements not expressly listed or elements inherent to such composition, step, method, article, or apparatus.

[0020] When a quantity, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper and lower preferred values, it should be understood as specifically disclosing all ranges formed by any pair of any upper or preferred value with any lower or preferred value, regardless of whether the range is disclosed individually.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Unless otherwise specified, the raw materials used in the following examples and comparative examples are commercially available industrial products or prepared by conventional methods, and conditions not specifically stated are conventional conditions. Example 1

[0022] S1, mix 100 parts by weight of vinyl-terminated polydimethylsiloxane, 120 parts by weight of alumina (average particle size 5 μm), 30 parts by weight of boron nitride (average particle size 10 μm), 1.5 parts by weight of silane coupling agent KH-550, 1 part by weight of platinum catalyst, and 8 parts by weight of dimethyl silicone oil until homogeneous, and degas under vacuum for 30 min; add methyl ethyl ketone solvent to adjust the viscosity to 3500 mPa·s, and control the curing amount of the adhesive to 85% to obtain thermally conductive silicone liquid. S2, the adhesive is applied to the release surface of the first release film (PET substrate, non-silicone release agent, release force 25g, thickness 36μm) by a scraping method, with a coating thickness of 0.12mm and a coating width of 1000mm; it is then sent into the first multi-gradient oven for low-temperature pre-curing, with the six oven sections having temperatures of 50℃, 60℃, 70℃, 80℃, 80℃, and 70℃ respectively, and a machine speed of 7m / min, forming a semi-cured first thermally conductive silicone layer; after exiting the oven, the first thermally conductive silicone layer is transferred to the first surface of a 60μm thick fiberglass mesh cloth by a pressing roller with a pressure of 0.25MPa; S3. Repeat step S2, apply the adhesive to the second release film (with the same specifications as the first release film) with a coating thickness of 0.12 mm, bake it with the same low-temperature pre-curing parameters, and then transfer it to the second surface of the fiberglass mesh with a pressure of 0.25 MPa to obtain a composite adhesive film. S4. The composite film is sent into the second multi-gradient oven for high-temperature curing. The temperatures of the six oven sections are 100℃, 120℃, 130℃, 130℃, 130℃, and 120℃ respectively. The machine speed is 5m / min. After curing, the film is rolled up to obtain a coatable double-sided high thermal conductivity film. Example 2

[0023] S1, 100 parts by weight of vinyl-terminated polydimethylsiloxane, 150 parts by weight of alumina (average particle size 5 μm), 20 parts by weight of silicon carbide (average particle size 8 μm), 10 parts by weight of graphene, 2 parts by weight of silane coupling agent KH-570, 1.2 parts by weight of platinum catalyst, and 10 parts by weight of dimethyl silicone oil are mixed and stirred evenly, and vacuum degassing is performed for 40 min; butanone solvent is added to adjust the viscosity to 5500 mPa·s, and the curing amount of the adhesive is controlled to be 90%, to obtain thermally conductive silicone liquid. S2, the adhesive is applied to the release surface of the first release film (PET substrate, non-silicone release agent, release force 30g, thickness 50μm) by a scraping method, with a coating thickness of 0.22mm and a coating width of 1260mm; it is then sent into the first multi-gradient oven for low-temperature pre-curing, with the six oven sections having temperatures of 50℃, 60℃, 70℃, 80℃, 80℃, and 70℃ respectively, and a machine speed of 6m / min, forming a semi-cured first thermally conductive silicone layer; after exiting the oven, the first thermally conductive silicone layer is transferred to the first surface of the 50μm thick fiberglass mesh cloth by a pressing roller with a pressure of 0.35MPa; S3. Repeat step S2, apply the adhesive to the second release film (with the same specifications as the first release film) with a coating thickness of 0.22 mm, bake it with the same low-temperature pre-curing parameters, and then transfer it to the second surface of the fiberglass mesh with a pressure of 0.35 MPa to obtain a composite adhesive film. S4. The composite film is sent into the second multi-gradient oven for high-temperature curing. The temperatures of the six oven sections are 100℃, 120℃, 130℃, 130℃, 130℃, and 120℃ respectively. The machine speed is 5m / min. After curing, the film is rolled up to obtain a coatable double-sided high thermal conductivity film. Example 3

[0024] S1. Mix 100 parts by weight of vinyl-terminated polydimethylsiloxane, 180 parts by weight of alumina (average particle size 10 μm), 40 parts by weight of zinc oxide (average particle size 3 μm), 15 parts by weight of aluminum powder (average particle size 5 μm), 2.5 parts by weight of silane coupling agent KH-550, 1.5 parts by weight of platinum catalyst, and 12 parts by weight of dimethyl silicone oil until homogeneous, and degas under vacuum for 45 min; add methyl ethyl ketone solvent to adjust the viscosity to 6500 mPa·s, and control the curing amount of the adhesive to 93% to obtain thermally conductive silicone liquid. S2, the adhesive is applied to the release surface of the first release film (PET substrate, non-silicone release agent, release force 35g, thickness 75μm) by a scraping method, with a coating thickness of 0.28mm and a coating width of 1000mm; it is then sent into the first multi-gradient oven for low-temperature pre-curing, with the six oven sections having temperatures of 50℃, 60℃, 70℃, 80℃, 80℃, and 70℃ respectively, and a machine speed of 5m / min, forming a semi-cured first thermally conductive silicone layer; after exiting the oven, the first thermally conductive silicone layer is transferred to the first surface of a 70μm thick fiberglass mesh cloth by a pressing roller with a pressure of 0.4MPa; S3. Repeat step S2, apply the adhesive to the second release film (with the same specifications as the first release film) with a coating thickness of 0.28 mm, bake it with the same low-temperature pre-curing parameters, and then transfer it to the second surface of the fiberglass mesh with a pressure of 0.4 MPa to obtain a composite adhesive film. S4. The composite film is sent into the second multi-gradient oven for high-temperature curing. The temperatures of the six oven sections are 100℃, 120℃, 130℃, 130℃, 130℃, and 120℃ respectively. The machine speed is 5m / min. After curing, the film is rolled up to obtain a coatable double-sided high thermal conductivity film.

[0025] Comparative Example 1 The difference from Example 2 is that in Comparative Example 1, the fiberglass mesh was laid flat on the coating table, and the thermally conductive silicone liquid prepared in Example 2 was directly scraped onto the first side of the fiberglass mesh. The coating thickness was set to 0.22 mm. The mesh was then placed in an oven and cured directly at 130°C (without a low-temperature pre-curing stage). The second side was then coated and cured in the same way.

[0026] Comparative Example 2 The difference from Example 2 is that in steps S2 and S3 of Comparative Example 2, after coating the release film, it is not pre-cured at low temperature, but directly sent to a high-temperature oven at 130°C for curing.

[0027] Comparative Example 3 The difference from Example 2 is that the thermally conductive filler in Comparative Example 3 uses only a single component of alumina (180 parts by weight). Comparative Example 4 The difference from Example 2 is that the viscosity of the adhesive in Comparative Example 4 is 1500 mPa·s.

[0028] Comparative Example 5 The difference from Example 2 is that the low-temperature pre-curing of Comparative Example 5 is a single temperature (80°C).

[0029] Comparative Example 6 The difference from Example 2 is that the high-temperature curing of Comparative Example 6 was a single temperature (130°C).

[0030] Performance testing 1. Thermal conductivity test: A thermal conductivity meter using the heat flow method was used. The sample size was 30mm×30mm. The test pressure was 40psi and the temperature was 25±2℃. The average value of 5 samples was taken.

[0031] 2. Withstand breakdown voltage test: A withstand voltage tester was used with a voltage rise rate of 500V / s and an electrode diameter of 25mm. The test environment was room temperature air medium, and the average value of 5 samples was taken.

[0032] 3. Thermal resistance test: A thermal resistance tester was used, with a test pressure of 40 psi. The sample thickness was based on the measured value, and the thermal resistance per unit area was calculated.

[0033] 4. Peel force test: The peel force of the release film was tested using a universal testing machine with a peel angle of 180° and a peel speed of 300 mm / min.

[0034] 5. Surface roughness test: The Ra value (arithmetic mean roughness) of the film surface is measured using a laser confocal microscope or a surface roughness meter. The sampling length is 0.8 mm, and the average value of 5 points is taken.

[0035] 6. Tensile strength and elongation at break test: A universal testing machine was used with dumbbell-shaped specimens and a tensile speed of 500 mm / min. The tensile strength and elongation at break were recorded.

[0036] Table 1 Performance test results of the examples and comparative examples

[0037] As shown in Table 1, the thermally conductive adhesive film prepared by the method of the present invention has a thickness of 0.24 mm to 0.56 mm, a thermal conductivity of 4.3 W / (m·K) to 5.2 W / (m·K), a surface roughness Ra value ≤ 0.48 μm, a breakdown voltage ≥ 1.8 kV, and a thickness tolerance controlled within ±0.03 mm. This indicates that the process of the present invention can obtain high-quality adhesive films with high thermal conductivity, high insulation, and a smooth and flat surface, and the maximum coating width reaches 1260 mm, realizing large-width continuous production. Compared with Example 2, In Comparative Example 1, during the coating process, a large amount of adhesive penetrated into the fiberglass mesh and flowed to the back side, resulting in severely uneven coating thickness, numerous pinholes and exposed fabric on the surface, and a rough and uneven adhesive film surface after curing, with thickness fluctuations exceeding ±40%. It was impossible to obtain a smooth and usable thermally conductive adhesive film, indicating that if the traditional direct coating process is used, the adhesive cannot penetrate the mesh to form a shape.

[0038] In Comparative Example 2, the adhesive rapidly cross-linked to form a film on the surface at high temperatures, preventing the internal solvent from escaping and resulting in numerous bubbles and pinhole defects. Simultaneously, rapid shrinkage generated internal stress, causing pre-peeling between the adhesive film and the release film. This prevented the fiberglass cloth from being smoothly bonded during transfer, resulting in numerous wrinkles on the finished product surface. This demonstrates that without low-temperature pre-curing and directly curing at high temperatures, the adhesive film develops bubbles and wrinkles, leading to a decrease in thermal conductivity.

[0039] The thermal conductivity of the film obtained in Comparative Example 3 was only 2.3 W / (m·K), which was much lower than that of Example 2 (4.8 W / (m·K). At the same time, due to the concentrated particle size distribution of the single filler, the filling efficiency was low, the viscosity of the adhesive solution increased significantly to 8500 mPa·s, the leveling properties of the coating deteriorated, and obvious scratches appeared on the surface, indicating that the thermal conductivity decreased when a single filler was used.

[0040] In Comparative Example 4, the low-viscosity adhesive flowed excessively during coating, making it impossible to maintain a stable coating thickness on the release film. When transferred to the fiberglass cloth, the adhesive excessively penetrated the mesh, causing the adhesive layers on both sides to become connected. This resulted in the loss of the fiberglass cloth's skeletal function, a decrease in the tensile strength of the finished product, and consequently, deterioration of the mechanical properties of the adhesive film and loss of coating precision control.

[0041] Comparative Example 5 used a single constant temperature pre-curing method at 80℃. The adhesive encountered high temperature immediately upon entering the oven, causing the surface solvent to evaporate rapidly and form a skin, hindering the subsequent escape of internal solvent. Although the total baking time was equivalent, the residual solvent inside expanded and formed microbubbles during the high-temperature curing stage, causing the breakdown voltage to drop from 2.8kV to 1.9kV and the surface roughness Ra value to increase from 0.42μm to 1.85μm. Simultaneously, excessive cross-linking of the surface layer formed a hard shell, reducing the bonding density with the fiberglass cloth during transfer and lowering the tensile strength. This indicates that using a gradient temperature control method—gradually increasing from 50℃ to 80℃ and then decreasing it back—during the low-temperature pre-curing stage allows the solvent to evaporate evenly from the surface inwards, resulting in a dense, defect-free adhesive film.

[0042] Comparative Example 6 used a single constant-temperature high-temperature curing method at 130℃. The composite film encountered the highest temperature immediately upon entering the oven, causing the silicone crosslinking reaction to proceed rapidly and intensely on the surface. This quickly formed a dense, highly crosslinked layer on the surface, hindering heat conduction to the interior and the escape of residual trace solvents, resulting in uneven crosslinking between the inner and outer layers. This unevenness generated internal stress, manifesting as slight warping after winding the finished product, and an increase in the release film peel force from 32g to 39g. Simultaneously, due to the decreased uniformity of the crosslinked network structure, the thermal conductivity decreased from 4.8 to 4.4 W / (m·K), and the breakdown voltage decreased from 2.8 to 2.3 kV. This demonstrates that using a gradient temperature increase / decrease of 100℃→120℃→130℃→120℃ during the high-temperature curing stage allows the crosslinking reaction to proceed smoothly from low to high, avoiding internal stress caused by thermal shock, and ensuring product dimensional stability and performance uniformity.

[0043] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above 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.

[0044] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above descriptions are merely specific embodiments of this application and are not intended to limit the scope of protection of this application. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application for those skilled in the art.

Claims

1. A method for preparing a coatable double-sided high thermal conductivity silicone film, characterized in that, Includes the following steps: S1. Mix the silicone matrix, thermally conductive filler and additives evenly and degas under vacuum. Add solvent to adjust the viscosity to 3000 mPa·s ~ 7000 mPa·s and control the curing amount of the adhesive liquid to 80%~95% to obtain thermally conductive silicone liquid. S2, the thermally conductive silicone liquid is applied to the release surface of the first release film by a scraping method, and a semi-cured first thermally conductive silicone layer is formed by low-temperature pre-curing. Then, the first thermally conductive silicone layer is transferred to the first surface of the fiberglass mesh cloth by a pressing roller. S3, the thermally conductive silicone liquid is coated onto the release surface of the second release film by a scraping method, and a semi-cured second thermally conductive silicone layer is formed by low-temperature pre-curing. Then, the second thermally conductive silicone layer is transferred to the second surface of the fiberglass mesh obtained in S2 by a pressing roller to obtain a composite adhesive film. S4. The composite film is cured at high temperature and then wound up to obtain a coatable double-sided high thermal conductivity film.

2. The method for preparing a coatable double-sided high thermal conductivity silicone film as described in claim 1, characterized in that, The silicone matrix comprises vinyl-terminated polydimethylsiloxane; The thermally conductive filler includes at least two of the following: metal filler, metal oxide filler, and non-metal filler. The metal filler includes at least one of silver powder, aluminum powder, and copper powder. The metal oxide includes at least one of aluminum oxide and zinc oxide. The non-metal filler includes at least one of boron nitride, silicon carbide, and graphene. The additives include dispersants, vulcanizing agents, and plasticizers.

3. The method for preparing a coatable double-sided high thermal conductivity silicone film as described in claim 2, characterized in that, In S2 and S3, low-temperature pre-curing is carried out in a first multi-gradient oven at a temperature of 50℃~80℃; in S4, high-temperature curing is carried out in a second multi-gradient oven at a temperature of 100℃~130℃.

4. The method for preparing a coatable double-sided high thermal conductivity silicone film as described in claim 3, characterized in that, The gradient temperatures of the first multi-gradient oven are 50℃, 60℃, 70℃, 80℃, 80℃ and 70℃ respectively; The gradient temperatures of the second multi-gradient oven are 100℃, 120℃, 130℃, 130℃, 130℃ and 120℃.

5. The method for preparing a coatable double-sided high thermal conductivity silicone film as described in claim 1, characterized in that, In steps S2 and S3, the pressing pressure of the pressing roller is 0.2MPa~0.4MPa.

6. The method for preparing a coatable double-sided high thermal conductivity silicone film as described in claim 1, characterized in that, The maximum coating width of the scraping method is 1260 mm.

7. The method for preparing a coatable double-sided high thermal conductivity silicone film as described in claim 1, characterized in that, The solvent is butanone.

8. The method for preparing a coatable double-sided high thermal conductivity silicone film as described in claim 1, characterized in that, The coating thickness of the first thermally conductive silicone layer is 0.1mm~0.3mm.

9. The method for preparing a coatable double-sided high thermal conductivity silicone film as described in claim 1, characterized in that, Both the first release film and the second release film are coated with a non-silicone release agent, and the release force of the non-silicone release agent is 20g~40g.

10. A coatable double-sided high thermal conductivity silicone film prepared by the preparation method according to any one of claims 1 to 9, characterized in that, It includes a first release film layer, a first thermally conductive silicone layer, a fiberglass mesh layer, a second thermally conductive silicone layer, and a first release film layer stacked in sequence.

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