A compressible self-adhesive heat-dissipating silicone rubber and a preparation method thereof

Abstract

The application relates to a compressible self-adhesive heat-dissipating silicone rubber and a preparation method thereof. The self-adhesive heat-dissipating silicone rubber comprises the following raw materials in parts by weight: 10-20 parts of vinyl silicone resin, 15-25 parts of silicone base glue, 0.01-0.05 parts of a colorant, 0.5-2 parts of side hydrogen-containing silicone oil, 0.5-2 parts of end hydrogen-containing silicone oil, 1-5 parts of an adhesion promoter, 50-70 parts of boron nitride, 0.01-0.1 parts of a high-temperature inhibitor and 0.01-0.1 parts of a catalyst. The heat-dissipating silicone rubber has the characteristics of high compression, low thermal resistance and self-adhesion, and after installation, the heat-dissipating silicone rubber has high insulation and high strength after complete curing.

Description

Technical Field

[0001] This invention relates to the field of heat dissipation silicone cloth technology, specifically to a compressible self-adhesive heat dissipation silicone cloth and its preparation method. Background Technology

[0002] In the electronics industry, thermal silicone cloth is widely used for heat dissipation and electrical safety isolation of heat sinks. It can effectively transfer heat from power components to the heat dissipation system, thereby ensuring the stable operation of the equipment.

[0003] Currently, conventional thermal silicone cloths generally have high hardness, low compression (e.g., less than 5%), and no adhesion, resulting in high contact thermal resistance and poor heat dissipation. While adhesive backing can solve the adhesion problem, it typically increases thermal resistance by more than 30%, significantly reducing heat dissipation. Furthermore, the adhesive material is generally acrylic, which greatly reduces overall reliability. Some thermal silicone cloths are used with thermal grease to reduce thermal resistance, but thermal grease typically has a short lifespan, such as only 2-3 years. Thermal silicone cloths are widely and critically used, especially in new energy equipment such as photovoltaics, energy storage, and electric vehicles. Besides providing high insulation and support, long-term stable and efficient heat dissipation is increasingly important for thermal silicone cloths. The long-term stable low thermal resistance of thermal silicone cloths under different application conditions indicates its ability to maintain long-term stable and efficient heat dissipation, better protecting the stability of electronic components. In new energy equipment such as photovoltaics, energy storage, and electric vehicles, long-term stable and efficient heat dissipation must be prioritized to ensure stable operation under different conditions and avoid equipment malfunctions due to thermal failure. Therefore, developing heat dissipation silicone cloth that meets the requirements is of great significance to the research and development of new energy equipment in my country. Summary of the Invention

[0004] In order to overcome the shortcomings and deficiencies of the existing technology, the present invention aims to provide a compressible self-adhesive heat dissipation silicone cloth. The heat dissipation silicone cloth is obtained by adding a high-temperature inhibitor and controlling the curing temperature and time to obtain a compressible self-adhesive heat dissipation silicone cloth with characteristics such as high compression, low thermal resistance and self-adhesion, effectively solving the problem of insufficient balance between thermal resistance, adhesion and reliability of existing heat dissipation insulation sheets.

[0005] Another objective of this invention is to provide a method for preparing a compressible self-adhesive heat-dissipating silicone cloth, wherein the preparation method is stable, easy to control, and conducive to industrial production.

[0006] The objective of this invention is achieved through the following technical solution: a compressible self-adhesive heat-dissipating silicone cloth, comprising the following raw materials in parts by weight: 10-20 parts of vinyl silicone resin, 15-25 parts of silicone base adhesive, 0.01-0.05 parts of colorant, 0.5-2 parts of side-containing hydrogen silicone oil, 0.5-2 parts of end-containing hydrogen silicone oil, 1-5 parts of tackifier, 50-70 parts of boron nitride, 0.01-0.1 parts of high-temperature inhibitor, and 0.01-0.1 parts of catalyst.

[0007] Furthermore, the vinyl silicone resin is a vinyl-terminated polydimethylsiloxane with a viscosity of 10,000-100,000 mPa·s at 25°C.

[0008] Furthermore, the silicone-based adhesive is methyl vinyl polysiloxane silicone, with a vinyl content of 0.2-1% and a silica content of 20-30%.

[0009] Furthermore, the hydrogen content of the side-containing hydrogen silicone oil is 0.1-0.5%.

[0010] Furthermore, the hydrogen content of the hydrogen-containing silicone oil is 0.05-0.1%.

[0011] Furthermore, the tackifier is at least one selected from γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropyltriethoxysilane.

[0012] This invention achieves high bonding strength without the need for a composite adhesive by combining a high-temperature inhibitor, vinyl silicone resin, and silicone-based adhesive, along with side-containing hydrogen silicone oil, end-containing hydrogen silicone oil, and the aforementioned tackifier. This avoids the problems of increased thermal resistance and aging failure caused by adhesive backing, and also provides high compressibility.

[0013] Furthermore, the colorant is an inorganic filler with coloring properties, specifically at least one of carbon black, iron oxide red, and mica iron oxide gray.

[0014] Furthermore, the high-temperature inhibitor is an organosilicon-modified alkynol. This invention utilizes an organosilicon-modified alkynol in combination with a catalyst for curing regulation, achieving good compatibility with tackifiers, vinyl silicone resins, and silicone-based adhesives. This results in a heat-dissipating silicone cloth that combines high compressibility, low thermal resistance, and self-adhesion, solving the problem of existing products struggling to balance thermal resistance, adhesion, and reliability. This makes it suitable for efficient heat dissipation in new energy equipment.

[0015] Furthermore, the boron nitride comprises 15-25 parts of small-particle-size boron nitride and 35-45 parts of large-particle-size boron nitride, wherein the particle size of the small-particle-size boron nitride is 0.5-2µm and the particle size of the large-particle-size boron nitride is 5-10µm. This invention, by employing a combination of small-particle-size and large-particle-size boron nitride, allows the small-particle-size particles to fill the gaps between the large-particle-size particles, forming continuous heat-conducting channels, which is beneficial for reducing thermal resistance.

[0016] Furthermore, the catalyst is a platinum catalyst.

[0017] The present invention also provides a method for preparing a compressible self-adhesive heat-dissipating silicone cloth, comprising the following steps: S1. Mix all raw materials evenly according to the proportions to obtain a mixed slurry; S2. Apply the mixed slurry onto the release film and dry it to form a silicone film; S3. Take one coated surface of a silicone film and laminate it to one side of the support layer, or take two coated surfaces of silicone films and laminate them to the two sides of the support layer respectively, and vulcanize them to obtain a heat dissipation silicone cloth.

[0018] Furthermore, in step S3, the high-temperature vulcanization pressure is 10-20 MPa, the temperature is 140-160°C, and the time is 5-20 min; the support layer is glass fiber cloth.

[0019] The preparation method of the present invention combines various raw materials and carefully designs the dosage ratio of each raw material. At the same time, by controlling the curing temperature and time, the self-adhesive heat dissipation silicone cloth obtained has the characteristics of high compression and self-adhesion. The preparation method is stable, easy to control, and conducive to industrial production.

[0020] The beneficial effects of this invention are as follows: This invention combines raw materials such as high-temperature inhibitors, vinyl silicone resin, silicone-based adhesive, side-containing hydrogen silicone oil, end-containing hydrogen silicone oil, and tackifiers to obtain a compressible self-adhesive heat-dissipating silicone cloth. The heat-dissipating silicone cloth has characteristics such as high compression, low thermal resistance, and self-adhesion. Its preparation method is stable and easy to control, and the resulting product has excellent comprehensive performance, which is conducive to industrial production. Detailed Implementation

[0021] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments. The content mentioned in the embodiments is not intended to limit the present invention. Unless otherwise specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed; unless the manufacturer of the reagents or instruments used is specified, they are all conventional products that can be purchased commercially.

[0022] In some embodiments of the present invention, a compressible self-adhesive heat-dissipating silicone cloth comprises the following raw materials in parts by weight: 10-20 parts vinyl silicone resin, 15-25 parts silicone base adhesive, 0.01-0.05 parts colorant, 0.5-2 parts side-containing hydrogen silicone oil, 0.5-2 parts end-containing hydrogen silicone oil, 1-5 parts tackifier, 50-70 parts boron nitride, 0.01-0.1 parts high-temperature inhibitor, and 0.01-0.1 parts catalyst.

[0023] The heat-dissipating silicone cloth of this invention possesses characteristics such as high compression, low thermal resistance, and self-adhesion. After installation and complete curing, it also exhibits the high insulation and high strength of conventional heat-dissipating silicone cloths. The preparation method of the self-adhesive heat-dissipating silicone cloth is stable, easy to control, and produces a product with superior overall performance, which is beneficial for industrial production. The heat-dissipating silicone cloth obtained by the method of this invention is applicable to the field of new energy equipment, especially for the bonding and heat dissipation of automotive electronic equipment.

[0024] In some embodiments of the present invention, the vinyl silicone resin is a vinyl-terminated polydimethylsiloxane with a viscosity of 10,000-100,000 mPa·s at 25°C.

[0025] In some embodiments of the present invention, the silicone base is methyl vinyl polysiloxane silicone, with a vinyl content of 0.2-1% and a silica content of 20-30%.

[0026] In some embodiments of the present invention, the side-chain hydrogen-containing silicone oil is a side-chain hydrogen-containing silicone oil with a hydrogen content of 0.1-0.5%.

[0027] In some embodiments of the present invention, the end-chain hydrogen-containing silicone oil is an end-chain hydrogen-containing silicone oil with a hydrogen content of 0.05-0.1%.

[0028] In some embodiments of the present invention, the tackifier is γ-aminopropyltriethoxysilane.

[0029] In some embodiments of the present invention, the colorant is an inorganic filler with coloring properties, specifically at least one of carbon black, iron oxide red, and mica iron oxide gray.

[0030] In some embodiments of the present invention, the high-temperature inhibitor is an organosilicon-modified alkynol, and the mass concentration of the organosilicon-modified alkynol is 95%.

[0031] In some embodiments of the present invention, the high-temperature inhibitor is at least one of trimethoxypropynyl alcohol and 3-(tert-butyldimethylsilyl)-2-propyn-1-ol.

[0032] In some embodiments of the present invention, the boron nitride comprises 15-25 parts of small-particle-size boron nitride and 35-45 parts of large-particle-size boron nitride, wherein the particle size of the small-particle-size boron nitride is 0.5-2µm and the particle size of the large-particle-size boron nitride is 5-10µm.

[0033] In some embodiments of the present invention, the catalyst is a platinum catalyst. The platinum catalyst is a cassiterite catalyst with a platinum content of 1000-5000 ppm.

[0034] In some embodiments of the present invention, the preparation method of the above-mentioned self-adhesive heat-dissipating silicone cloth includes the following steps: S1. Mix all raw materials evenly according to the proportions to obtain a mixed slurry; S2. The mixed slurry is coated onto the release film and dried to form a silicone film including the release film and a silicone layer; S3. Take one silicone film coating surface and laminate it to one side of the support layer, or take two silicone films coating surfaces and laminate them to the two sides of the support layer respectively, and vulcanize them at 10-20MPa and 140-160℃ for 5-20 minutes to obtain a heat dissipation silicone cloth; the heat dissipation silicone cloth includes a support layer and two silicone layers respectively disposed on the two sides of the support layer, or forms a support layer and silicone layers respectively disposed on one side of the support layer; the support layer is a glass fiber cloth layer.

[0035] Example 1 In this embodiment, a compressible self-adhesive heat dissipation silicone cloth comprises the following raw materials in parts by weight: 12 parts vinyl silicone resin, 24 parts silicone base adhesive, 0.02 parts colorant, 1 part side-containing hydrogen silicone oil, 1.9 parts end-containing hydrogen silicone oil, 2 parts tackifier, 61 parts boron nitride, 0.02 parts high-temperature inhibitor, and 0.06 parts platinum catalyst.

[0036] Furthermore, the vinyl silicone resin is a vinyl-terminated polydimethylsiloxane, specifically Keqi Polymer Materials' vinyl-terminated polydimethylsiloxane V-20000. The silicone-based adhesive uses Dongjue 110-3S methyl vinyl polysiloxane, and the silica content in the silicone-based adhesive is 25 wt%.

[0037] Furthermore, the side-containing hydrogen silicone oil is Runhe Material RH-H33 side-containing hydrogen silicone oil. The end-containing hydrogen silicone oil is Runhe Material RH-DH07 end-containing hydrogen silicone oil.

[0038] Furthermore, the tackifier is γ-aminopropyltriethoxysilane.

[0039] Furthermore, the colorant is carbon black. The high-temperature inhibitor is trimethylsilylpropynol.

[0040] Furthermore, the boron nitride comprises 18 parts of small-particle-size boron nitride and 43 parts of large-particle-size boron nitride, wherein the particle size of the small-particle-size boron nitride is 0.5-2µm and the particle size of the large-particle-size boron nitride is 5-10µm.

[0041] Furthermore, the platinum catalyst is a cassiterite catalyst with a platinum content of 3000 ppm.

[0042] In this embodiment, the preparation method of the above-mentioned self-adhesive heat dissipation silicone cloth includes the following steps: S1. Mix all raw materials evenly according to the proportions to obtain a mixed slurry; S2. The mixed slurry is coated onto two release films separately and dried to form a silicone film; S3. The coated surfaces of the two silicone films are respectively bonded to the two sides of the glass fiber cloth and vulcanized at high temperature. The vulcanization is carried out at 15MPa and 150℃ for 8 minutes to obtain heat dissipation silicone cloth.

[0043] Example 2 In this embodiment, a compressible self-adhesive heat dissipation silicone cloth comprises the following raw materials in parts by weight: 15 parts vinyl silicone resin, 20 parts silicone base adhesive, 0.03 parts colorant, 1.5 parts side-containing hydrogen silicone oil, 1.5 parts end-containing hydrogen silicone oil, 2 parts tackifier, 60 parts boron nitride, 0.05 parts high-temperature inhibitor, and 0.08 parts platinum catalyst.

[0044] Furthermore, the vinyl silicone resin is a vinyl-terminated polydimethylsiloxane with a viscosity of 10,000-100,000 mPa·s at 25°C.

[0045] Furthermore, the tackifier is γ-aminopropyltriethoxysilane.

[0046] Furthermore, the boron nitride comprises 20 parts of small-particle-size boron nitride and 40 parts of large-particle-size boron nitride, wherein the particle size of the small-particle-size boron nitride is 0.5-2µm and the particle size of the large-particle-size boron nitride is 5-10µm.

[0047] The rest of the content of this embodiment is the same as that of Embodiment 1, and will not be repeated here.

[0048] Example 3 In this embodiment, a compressible self-adhesive heat-dissipating silicone cloth comprises the following raw materials in parts by weight: 10 parts vinyl silicone resin, 15 parts silicone base adhesive, 0.01 parts colorant, 0.5 parts side-containing hydrogen silicone oil, 0.5 parts end-containing hydrogen silicone oil, 1 part tackifier, 50 parts boron nitride, 0.01 parts high-temperature inhibitor, and 0.01 parts platinum catalyst.

[0049] Furthermore, the vinyl silicone resin is a vinyl-terminated polydimethylsiloxane with a viscosity of 10,000-100,000 mPa·s at 25°C.

[0050] Furthermore, the tackifier is γ-aminopropyltriethoxysilane.

[0051] Furthermore, the colorant is iron oxide red.

[0052] Furthermore, the boron nitride comprises 15 parts of small-particle-size boron nitride and 35 parts of large-particle-size boron nitride, wherein the particle size of the small-particle-size boron nitride is 0.5-2µm and the particle size of the large-particle-size boron nitride is 5-10µm.

[0053] In this embodiment, the preparation method of the above-mentioned self-adhesive heat dissipation silicone cloth includes the following steps: S1. Mix all raw materials evenly according to the proportions to obtain a mixed slurry; S2. The mixed slurry is coated onto two release films separately and dried to form a silicone film; S3. The coated surfaces of the two silicone films are respectively bonded to the two sides of the glass fiber cloth, and then vulcanized at 10MPa and 160℃ for 15 minutes to obtain the heat dissipation silicone cloth.

[0054] The rest of the content of this embodiment is the same as that of Embodiment 1, and will not be repeated here.

[0055] Example 4 In this embodiment, a compressible self-adhesive heat dissipation silicone cloth comprises the following raw materials in parts by weight: 20 parts vinyl silicone resin, 25 parts silicone base adhesive, 0.05 parts colorant, 2 parts side-containing hydrogen silicone oil, 2 parts end-containing hydrogen silicone oil, 5 parts tackifier, 70 parts boron nitride, 0.1 parts high-temperature inhibitor, and 0.1 parts platinum catalyst.

[0056] Furthermore, the tackifier is γ-aminopropyltriethoxysilane.

[0057] Furthermore, the colorant is mica iron oxide ash. The high-temperature inhibitor is 3-(tert-butyldimethylsilyl)-2-propyn-1-ol.

[0058] Furthermore, the boron nitride comprises 15-25 parts of small-particle-size boron nitride and 35-45 parts of large-particle-size boron nitride, wherein the particle size of the small-particle-size boron nitride is 0.5-2µm and the particle size of the large-particle-size boron nitride is 5-10µm.

[0059] In this embodiment, the preparation method of the above-mentioned self-adhesive heat dissipation silicone cloth includes the following steps: Includes the following steps: S1. Mix all raw materials evenly according to the proportions to obtain a mixed slurry; S2. The mixed slurry is coated onto two release films separately and dried to form a silicone film; S3. The coated surfaces of the two silicone films are respectively bonded to the two sides of the glass fiber cloth, and then vulcanized at 20MPa and 140℃ for 10 minutes to obtain the heat dissipation silicone cloth.

[0060] The rest of the content of this embodiment is the same as that of Embodiment 1, and will not be repeated here.

[0061] Comparative Example 1 The difference between this comparative example and Example 1 is that: in this comparative example, a compressible self-adhesive heat dissipation silicone cloth includes the following raw materials in parts by weight: 12 parts vinyl silicone resin, 24 parts silicone base adhesive, 0.02 parts colorant, 1 part side-containing hydrogen silicone oil, 1.9 parts end-containing hydrogen silicone oil, 61 parts boron nitride, 0.02 parts ethynylcyclohexanol, and 0.06 parts platinum catalyst.

[0062] The rest of the contents of this comparative example are the same as those of Example 1, and will not be repeated here.

[0063] Comparative Example 2 The difference between this comparative example and Example 1 is that: in this comparative example, a compressible self-adhesive heat dissipation silicone cloth includes the following raw materials in parts by weight: 12 parts vinyl silicone resin, 24 parts silicone base adhesive, 0.02 parts colorant, 1 part side-containing hydrogen silicone oil, 1.9 parts end-containing hydrogen silicone oil, 61 parts boron nitride, 0.02 parts ethynylcyclohexanol, and 0.06 parts platinum catalyst.

[0064] The rest of the contents of this comparative example are the same as those of Example 1, and will not be repeated here.

[0065] The raw material compositions of Embodiment 1 and Comparative Examples 1-2 of the present invention are shown in Table 1 below: The performance of the self-adhesive heat-dissipating silicone cloths prepared in Example 1 and Comparative Examples 1-2 was measured, and the test results are shown in Table 2 below: The self-adhesive thermal silicone cloth of Example 1 and Comparative Example 1 comprises, from top to bottom, a silicone layer, a fiberglass cloth layer, and a silicone layer; the thickness of the fiberglass cloth layer is 0.10 mm, and the silicone layers on both sides of the fiberglass cloth layer have the same thickness. The thermal silicone cloth of Comparative Example 2 comprises, from top to bottom, an adhesive layer, a silicone layer, a fiberglass cloth layer, and a silicone layer; the thickness of the fiberglass cloth layer is 0.10 mm, and the silicone layers on both sides of the fiberglass cloth layer have the same thickness; the adhesive layer uses commercially available acrylic adhesive with a thickness of 0.01 mm. The compression ratio of the self-adhesive thermal silicone cloth was tested according to ASTM D575, with a pressure of 1 MPa and a holding time of 30 s. The adhesive strength was tested according to ASTM D3330, measuring 180° peel strength at a test speed of 300 mm / min. Thermal conductivity was tested according to ASTM D5470; the thermal resistance after high-temperature treatment was tested as follows: the sample was treated at 150℃ for 1000h and then tested according to ASTM D5470.

[0066] In summary, this invention combines high-temperature inhibitors, vinyl silicone resin, silicone-based adhesive, side-containing hydrogen silicone oil, end-containing hydrogen silicone oil, and tackifiers to obtain a compressible self-adhesive thermal silicone cloth. This thermal silicone cloth possesses high compression, low thermal resistance, and self-adhesive properties. After installation and complete curing, it also exhibits the high insulation and high strength of conventional thermal silicone cloths. The thermal silicone cloth obtained by this invention has a compression ratio of over 30% and a thermal resistance of 0.1-0.3℃·in. 2 With a bonding strength of 6.0-9.0 N / 25 mm and a thermal resistance increase of <10% after 150℃ / 1000H, it is suitable for bonding and heat dissipation in the field of new energy equipment, especially automotive electronic equipment.

[0067] The above embodiments are preferred implementations of the present invention. In addition, the present invention can be implemented in other ways. Any obvious substitutions without departing from the concept of the present invention are within the protection scope of the present invention.

Claims

1. A compressible self-adhesive heat-dissipating silicone cloth, characterized in that: The raw materials include the following parts by weight: 10-20 parts vinyl silicone resin, 15-25 parts silicone base adhesive, 0.01-0.05 parts colorant, 0.5-2 parts side-containing hydrogen silicone oil, 0.5-2 parts end-containing hydrogen silicone oil, 1-5 parts tackifier, 50-70 parts boron nitride, 0.01-0.1 parts high-temperature inhibitor, and 0.01-0.1 parts catalyst.

2. The compressible self-adhesive heat-dissipating silicone cloth according to claim 1, characterized in that: The vinyl silicone resin is a vinyl-terminated polydimethylsiloxane with a viscosity of 10,000-100,000 mPa·s at 25°C.

3. The compressible self-adhesive heat-dissipating silicone cloth according to claim 1, characterized in that: The silicone-based adhesive is methyl vinyl polysiloxane silicone, with a vinyl content of 0.2-1% and a silica content of 20-30%.

4. The compressible self-adhesive heat-dissipating silicone cloth according to claim 1, characterized in that: The hydrogen content of the hydrogen-containing silicone oil is 0.1-0.5%.

5. The compressible self-adhesive heat-dissipating silicone cloth according to claim 1, characterized in that: The hydrogen content of the hydrogen-containing silicone oil is 0.05-0.1%.

6. The compressible self-adhesive heat-dissipating silicone cloth according to claim 1, characterized in that: The thickener is at least one of γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropyltriethoxysilane.

7. The compressible self-adhesive heat-dissipating silicone cloth according to claim 1, characterized in that: The colorant is at least one of carbon black, iron oxide red, and mica iron oxide gray.

8. The compressible self-adhesive heat-dissipating silicone cloth according to claim 1, characterized in that: The high-temperature inhibitor is an organosilicon-modified alkynol.

9. The compressible self-adhesive heat-dissipating silicone cloth according to claim 1, characterized in that: The boron nitride comprises 15-25 parts of small-particle-size boron nitride and 35-45 parts of large-particle-size boron nitride, wherein the particle size of the small-particle-size boron nitride is 0.5-2µm and the particle size of the large-particle-size boron nitride is 5-10µm.

10. A method for preparing a compressible self-adhesive heat-dissipating silicone cloth as described in any one of claims 1-9, characterized in that: Includes the following steps: S1. Mix all raw materials evenly according to the proportions to obtain a mixed slurry; S2. Apply the mixed slurry onto the release film and dry it to form a silicone film; S3. Take one coated surface of a silicone film and laminate it to one side of the support layer, or take two coated surfaces of silicone films and laminate them to the two sides of the support layer respectively, and vulcanize them to obtain a heat dissipation silicone cloth.

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