Single-component curable 18W heat-conducting gel and preparation method thereof
By modifying aluminum nitride with hydroxyl silicone oil and curing it at room temperature, the problems of slow extrusion rate and difficult dispensing of thermally conductive gel were solved, achieving high thermal conductivity and convenient dispensing process.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-20
- Publication Date
- 2026-04-07
AI Technical Summary
Existing thermal conductive gels have a slow extrusion rate, which makes dispensing difficult, causes clogging of the needle, and makes it difficult to achieve a uniform and smooth finish.
Aluminum nitride was modified with hydroxyl silicone oil to form Si-O-Al covalent bonds, which improved its compatibility with silicone oil. It was then cured at room temperature using a platinum catalyst. Modified fumed silica was added to improve dispersibility and prevent agglomeration.
It increases the extrusion rate of the thermally conductive gel, facilitates dispensing, prevents powder agglomeration, forms a uniform thixotropic structure, and enhances thermal conductivity.
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Abstract
Description
Technical Field
[0001] This application relates to the technical field of thermally conductive materials, and in particular to a single-component curable 18W thermally conductive gel and its preparation method. Background Technology
[0002] Thermally conductive gel is a paste-like thermally conductive material with good thixotropic properties. It is easy to apply and will not flow and contaminate surrounding components. A thermally conductive gel with a high thermal conductivity forms a dense, continuous thermally conductive network within the matrix, allowing heat to be transferred efficiently along these pathways and significantly reducing thermal resistance. However, a high thermal conductivity also means a high powder content, which greatly increases the viscosity of the system, resulting in a slower extrusion rate, making dispensing difficult, clogging the nozzle, and making it difficult to dispense a uniform and smooth gel. Summary of the Invention
[0003] To improve the extrusion rate of the gel and facilitate dispensing, this application provides a single-component curable 18W thermally conductive gel and its preparation method.
[0004] In the first aspect, this application provides a single-component, curable 18W thermal conductive gel, which adopts the following technical solution: A single-component curable 18W thermal conductive gel, wherein the raw materials of the thermal conductive gel include the following components in parts by weight: 93-97 parts of vinyl silicone oil, 3-7 parts of hydrogen-containing silicone oil, 3950-4050 parts of hydroxyl silicone oil-modified aluminum nitride, and 0.1-0.3 parts of catalyst.
[0005] By employing the above technical solution, aluminum nitride is modified with hydroxyl silicone oil, forming strong Si-O-Al covalent bonds. This transforms the hydrophilic / polar surface into a hydrophobic / oleophilic surface. The modified aluminum nitride powder exhibits significantly improved compatibility with silicone oil, resolving its dispersibility and interface issues in polymer matrices and fully utilizing its thermal conductivity. The long chains of silicone oil molecules attached to the powder surface act like an organic polymer "coat," preventing direct contact and agglomeration when the powder particles approach each other. Furthermore, the resulting gel has a faster extrusion rate, facilitating dispensing. The reaction principle is shown in the figure below. .
[0006] In one specific implementation, the viscosity of both the vinyl silicone oil and the hydrogen-containing silicone oil is 50 cps.
[0007] In one specific implementation, the method for preparing the hydroxyl silicone oil-modified aluminum nitride includes the following steps: Aluminum nitride powder was pre-dried at 110°C for 2 hours, then an organic solvent was added and the mixture was evenly dispersed. Hydroxy silicone oil was then added and the temperature was raised to 110°C. Subsequently, dibutyltin dilaurate was added to react the mixture, and the product was separated to obtain hydroxy silicone oil modified aluminum nitride.
[0008] In one specific implementation, the aluminum nitride powder comprises a mixture of aluminum nitride powder with a particle size of less than 1 μm, aluminum nitride powder with a particle size of 5 μm, and aluminum nitride powder with a particle size of 150 μm.
[0009] In one specific implementation, the weight ratio of the hydroxyl silicone oil to the aluminum nitride powder is (0.5-1.5):100; the weight ratio of the dibutyltin dilaurate to the hydroxyl silicone oil is (0.5-1.5):100.
[0010] By adopting the above technical solution, aluminum nitride powder forms a dense thermal conduction path by utilizing multi-particle size gradation, and further limits the ratio of hydroxyl silicone oil, aluminum nitride powder, and dibutyltin dilaurate, thereby improving the modification effect of aluminum nitride powder.
[0011] In one specific implementation, the catalyst comprises a platinum catalyst.
[0012] By adopting the above technical solution, hydroxyl silicone oil-modified aluminum nitride is dispersed in vinyl silicone oil, and a certain proportion of hydrogen-containing silicone oil is added. The mixture is then cured at room temperature using a platinum catalyst. The principle diagram of the hydrosilylation reaction is as follows: .
[0013] In one specific implementation, the thermally conductive gel further comprises 10-30 parts by weight of modified fumed silica; the preparation method of the modified fumed silica includes the following steps: Hydrophilic fumed silica was dried at 120°C for 4 hours to obtain a dried material; the dried material was dispersed in anhydrous ethanol and ultrasonically dispersed to obtain a suspension. Hexamethyldisilazane was added dropwise at 60°C. After the addition was complete, the temperature was raised to 78°C and the reaction was continued at this temperature for 6 hours. After the reaction was completed, the mixture was cooled to room temperature, and the solid product was separated by filtration and washed with anhydrous ethanol. The washed solid product was dried at 80°C for 8 hours and then pulverized to obtain modified fumed silica.
[0014] By adopting the above technical solution, hexamethyldisilazane is used to pretreat the surface of hydrophilic fumed silica. The treated silica surface is a hydrophobic layer with excellent compatibility with hydroxyl silicone oil modified aluminum nitride, and can be uniformly interspersed between fillers. Its hydrophobic surface has strong affinity with silicone oil matrix, and requires less shear force during dispersion, which can form a uniform thixotropic structure more quickly and prevent thermally conductive fillers from settling.
[0015] In one specific implementation, the weight ratio of the hydrophilic fumed silica, the anhydrous ethanol, and the hexamethyldisilazane is 100:(390-400):(25-30).
[0016] Secondly, this application provides a method for preparing a single-component, curable 18W thermally conductive gel, which employs the following technical solution: A method for preparing a single-component, curable 18W thermally conductive gel includes the following steps: Vinyl silicone oil, hydrogen-containing silicone oil, hydroxyl silicone oil-modified aluminum nitride, and other raw materials were kneaded at 90°C for 30 minutes, and then a catalyst was added to obtain a thermally conductive gel.
[0017] By adopting the above technical solution, vinyl silicone oil, hydrogen-containing silicone oil, hydroxyl silicone oil-modified aluminum nitride and other raw materials are first kneaded together, and then a catalyst is added to obtain a thermally conductive gel with a high extrusion rate and easy dispensing.
[0018] In summary, this application includes at least one of the following beneficial technical effects: In this application, aluminum nitride is modified with hydroxyl silicone oil to form strong Si-O-Al covalent bonds, thereby transforming the hydrophilic / polar surface into a hydrophobic / oleophilic surface. The modified aluminum nitride powder has significantly improved compatibility in silicone oil, solving its dispersion and interface problems in the polymer matrix and fully utilizing its thermal conductivity. The long chains of silicone oil molecules attached to the powder surface are like putting an organic polymer "coat" on the powder. When the powder particles come close to each other, the organic polymer will generate a steric hindrance effect, preventing the powder particles from directly contacting each other, effectively preventing agglomeration, and the resulting gel has a faster extrusion rate, which is convenient for dispensing. In this application, hydroxyl silicone oil modified aluminum nitride is dispersed in vinyl silicone oil, a certain proportion of hydrogen-containing silicone oil is added, and it is cured at room temperature by a platinum catalyst. The method in this application involves first kneading vinyl silicone oil, hydrogen-containing silicone oil, hydroxyl silicone oil-modified aluminum nitride, and other raw materials, and then adding a catalyst to obtain a thermally conductive gel with a high extrusion rate and easy dispensing. Detailed Implementation
[0019] The present application will be further described in detail below with reference to the embodiments.
[0020] All raw materials used in the examples are commercially available. The vinyl silicone oil is model DW3432; the hydrogen-containing silicone oil is model JC-202; the hydroxyl silicone oil has CAS number 58130-04-4; the platinum catalyst is model PL-5; and the hydrophilic fumed silica is model TS610. Preparation Example
[0021] Preparation Example 1 Preparation Example 1 provides a method for preparing hydroxyl silicone oil modified aluminum nitride, comprising the following steps: Aluminum nitride powder was pre-dried at 110℃ for 2 hours, then an organic solvent was added and the mixture was uniformly dispersed for 1 hour. Hydroxy silicone oil was then added and the temperature was raised to 110℃. Subsequently, dibutyltin dilaurate was added and the reaction proceeded for 4 hours. The product was separated, washed, dried, ground, and passed through a 200-mesh sieve to obtain hydroxy silicone oil-modified aluminum nitride. The aluminum nitride powder consisted of a mixture of aluminum nitride powder with a particle size less than 1 μm, aluminum nitride powder with a particle size of 5 μm, and aluminum nitride powder with a particle size of 150 μm, with a weight ratio of 800:1200:2000. The organic solvent was toluene, with a weight ratio of aluminum nitride powder to organic solvent of 1:10. The weight ratio of hydroxy silicone oil to aluminum nitride powder was 0.5:100, and the weight ratio of dibutyltin dilaurate to hydroxy silicone oil was 0.5:100.
[0022] Preparation Example 2 Preparation Example 2 provides a method for preparing hydroxyl silicone oil modified aluminum nitride, comprising the following steps: Aluminum nitride powder was pre-dried at 110℃ for 2 hours, then an organic solvent was added and the mixture was uniformly dispersed for 1 hour. Hydroxy silicone oil was then added and the temperature was raised to 110℃. Subsequently, dibutyltin dilaurate was added and the reaction proceeded for 4 hours. The product was separated, washed, dried, ground, and passed through a 200-mesh sieve to obtain hydroxy silicone oil-modified aluminum nitride. The aluminum nitride powder consisted of a mixture of aluminum nitride powder with a particle size less than 1 μm, aluminum nitride powder with a particle size of 5 μm, and aluminum nitride powder with a particle size of 150 μm, with a weight ratio of 800:1200:2000. The organic solvent was toluene, with a weight ratio of aluminum nitride powder to organic solvent of 1:10. The weight ratio of hydroxy silicone oil to aluminum nitride powder was 1:100, and the weight ratio of dibutyltin dilaurate to hydroxy silicone oil was 1:100.
[0023] Preparation Example 3 Preparation Example 3 provides a method for preparing hydroxyl silicone oil modified aluminum nitride, comprising the following steps: Aluminum nitride powder was pre-dried at 110℃ for 2 hours, then an organic solvent was added and the mixture was uniformly dispersed for 1 hour. Hydroxy silicone oil was then added and the temperature was raised to 110℃. Subsequently, dibutyltin dilaurate was added and the reaction proceeded for 4 hours. The product was separated, washed, dried, ground, and passed through a 200-mesh sieve to obtain hydroxy silicone oil-modified aluminum nitride. The aluminum nitride powder consisted of a mixture of aluminum nitride powder with a particle size less than 1 μm, aluminum nitride powder with a particle size of 5 μm, and aluminum nitride powder with a particle size of 150 μm, with a weight ratio of 800:1200:2000. The organic solvent was toluene, with a weight ratio of aluminum nitride powder to organic solvent of 1:10. The weight ratio of hydroxy silicone oil to aluminum nitride powder was 1.5:100, and the weight ratio of dibutyltin dilaurate to hydroxy silicone oil was 1.5:100.
[0024] Preparation Example 4 Preparation Example 4 provides a method for preparing hydroxyl silicone oil modified aluminum nitride, comprising the following steps: Aluminum nitride powder was pre-dried at 110℃ for 2 hours, then an organic solvent was added and the mixture was uniformly dispersed for 1 hour. Hydroxy silicone oil was then added and the temperature was raised to 110℃. Subsequently, dibutyltin dilaurate was added and the reaction proceeded for 4 hours. The product was separated, washed, dried, ground, and passed through a 200-mesh sieve to obtain hydroxy silicone oil-modified aluminum nitride. The aluminum nitride powder consisted of a mixture of aluminum nitride powder with a particle size less than 1 μm, aluminum nitride powder with a particle size of 5 μm, and aluminum nitride powder with a particle size of 150 μm, with a weight ratio of 600:1200:2200. The organic solvent was toluene, with a weight ratio of aluminum nitride powder to organic solvent of 1:10. The weight ratio of hydroxy silicone oil to aluminum nitride powder was 1.5:100, and the weight ratio of dibutyltin dilaurate to hydroxy silicone oil was 1.5:100.
[0025] Preparation Example 5 Preparation Example 5 provides a method for preparing hydroxyl silicone oil modified aluminum nitride, comprising the following steps: Aluminum nitride powder was pre-dried at 110℃ for 2 hours, then an organic solvent was added and the mixture was uniformly dispersed for 1 hour. Hydroxy silicone oil was then added and the temperature was raised to 110℃. Subsequently, dibutyltin dilaurate was added and the reaction proceeded for 4 hours. The product was separated, washed, dried, ground, and passed through a 200-mesh sieve to obtain hydroxy silicone oil-modified aluminum nitride. The aluminum nitride powder consisted of a mixture of aluminum nitride powder with a particle size less than 1 μm, aluminum nitride powder with a particle size of 5 μm, and aluminum nitride powder with a particle size of 150 μm, with a weight ratio of 1200:1000:1800. The organic solvent was toluene, with a weight ratio of aluminum nitride powder to organic solvent of 1:10. The weight ratio of hydroxy silicone oil to aluminum nitride powder was 1.5:100, and the weight ratio of dibutyltin dilaurate to hydroxy silicone oil was 1.5:100.
[0026] Preparation Example 6 Preparation Example 6 provides a method for preparing hydroxyl silicone oil modified aluminum nitride, comprising the following steps: Aluminum nitride powder was pre-dried at 110℃ for 2 hours, then an organic solvent was added and the mixture was uniformly dispersed for 1 hour. Hydroxy silicone oil was then added and the temperature was raised to 110℃. Subsequently, dibutyltin dilaurate was added and the reaction proceeded for 4 hours. The product was separated, washed, dried, ground, and passed through a 200-mesh sieve to obtain hydroxy silicone oil-modified aluminum nitride. The aluminum nitride powder consisted of a mixture of aluminum nitride powder with a particle size less than 1 μm, aluminum nitride powder with a particle size of 5 μm, and aluminum nitride powder with a particle size of 150 μm, with a weight ratio of 400:2000:1600. The organic solvent was toluene, with a weight ratio of aluminum nitride powder to organic solvent of 1:10. The weight ratio of hydroxy silicone oil to aluminum nitride powder was 1.5:100, and the weight ratio of dibutyltin dilaurate to hydroxy silicone oil was 1.5:100.
[0027] Preparation Example 7 Preparation Example 7 provides a method for preparing hydroxyl silicone oil modified aluminum nitride, comprising the following steps: Aluminum nitride powder was pre-dried at 110℃ for 2 hours, then an organic solvent was added and the mixture was uniformly dispersed for 1 hour. Hydroxy silicone oil was then added and the temperature was raised to 110℃. Subsequently, dibutyltin dilaurate was added and the reaction proceeded for 4 hours. The product was separated, washed, dried, ground, and passed through a 200-mesh sieve to obtain hydroxy silicone oil-modified aluminum nitride. The aluminum nitride powder consisted of a mixture of aluminum nitride powder with a particle size less than 1 μm, aluminum nitride powder with a particle size of 5 μm, and aluminum nitride powder with a particle size of 150 μm, with a weight ratio of 800:800:2400. The organic solvent was toluene, with a weight ratio of aluminum nitride powder to organic solvent of 1:10. The weight ratio of hydroxy silicone oil to aluminum nitride powder was 1.5:100, and the weight ratio of dibutyltin dilaurate to hydroxy silicone oil was 1.5:100.
[0028] Preparation Example 8 Preparation Example 8 provides a method for preparing modified fumed silica, comprising the following steps: Hydrophilic fumed silica was dried at 120°C for 4 hours to obtain a dried material; the dried material was dispersed in anhydrous ethanol and ultrasonically dispersed to obtain a suspension. Hexamethyldisilazane was added dropwise at 60℃. After the addition was complete, the temperature was raised to 78℃ and the reaction was continued at this temperature for 6 hours. After the reaction was completed, the mixture was cooled to room temperature, and the solid product was separated by filtration and washed with anhydrous ethanol. The washed solid product was dried at 80℃ for 8 hours, pulverized, and passed through a 200-mesh sieve to obtain modified fumed silica. The weight ratio of hydrophilic fumed silica, anhydrous ethanol, and hexamethyldisilazane was 100:390:25.
[0029] Preparation Example 9 Preparation Example 9 provides a method for preparing modified fumed silica, comprising the following steps: Hydrophilic fumed silica was dried at 120°C for 4 hours to obtain a dried material; the dried material was dispersed in anhydrous ethanol and ultrasonically dispersed to obtain a suspension. Hexamethyldisilazane was added dropwise at 60℃. After the addition was complete, the temperature was raised to 78℃ and the reaction was continued at this temperature for 6 hours. After the reaction was completed, the mixture was cooled to room temperature, and the solid product was separated by filtration and washed with anhydrous ethanol. The washed solid product was dried at 80℃ for 8 hours, pulverized, and passed through a 200-mesh sieve to obtain modified fumed silica. The weight ratio of hydrophilic fumed silica, anhydrous ethanol, and hexamethyldisilazane was 100:395:27.5.
[0030] Preparation Example 10 Preparation Example 10 provides a method for preparing modified fumed silica, comprising the following steps: Hydrophilic fumed silica was dried at 120°C for 4 hours to obtain a dried material; the dried material was dispersed in anhydrous ethanol and ultrasonically dispersed to obtain a suspension. Hexamethyldisilazane was added dropwise at 60℃. After the addition was complete, the temperature was raised to 78℃ and the reaction was continued at this temperature for 6 hours. After the reaction was completed, the mixture was cooled to room temperature, and the solid product was separated by filtration and washed with anhydrous ethanol. The washed solid product was dried at 80℃ for 8 hours, pulverized, and passed through a 200-mesh sieve to obtain modified fumed silica. The weight ratio of hydrophilic fumed silica, anhydrous ethanol, and hexamethyldisilazane was 100:400:30. Example
[0031] Example 1 Example 1 provides a method for preparing a one-component curable 18W thermally conductive gel, comprising the following steps: 95g of vinyl silicone oil, 5g of hydrogen-containing silicone oil, and 4000g of hydroxyl silicone oil-modified aluminum nitride from Preparation Example 1 were kneaded at 90°C for 30 minutes, followed by the addition of 0.2g of catalyst to obtain a thermally conductive gel. The viscosity of both the vinyl silicone oil and the hydrogen-containing silicone oil was 50 cps. The catalyst was a platinum catalyst.
[0032] Example 2 Example 2 provides a method for preparing a single-component curable 18W thermally conductive gel, comprising the following steps: 95g of vinyl silicone oil, 5g of hydrogen-containing silicone oil, and 4000g of hydroxyl silicone oil-modified aluminum nitride from Preparation Example 2 were kneaded at 90°C for 30 minutes, followed by the addition of 0.2g of catalyst to obtain a thermally conductive gel. The viscosity of both the vinyl silicone oil and the hydrogen-containing silicone oil was 50 cps. The catalyst was a platinum catalyst.
[0033] Example 3 Example 3 provides a method for preparing a single-component curable 18W thermally conductive gel, comprising the following steps: 95g of vinyl silicone oil, 5g of hydrogen-containing silicone oil, and 4000g of hydroxyl silicone oil-modified aluminum nitride from Preparation Example 3 were kneaded at 90°C for 30 minutes, followed by the addition of 0.2g of catalyst to obtain a thermally conductive gel. The viscosity of both the vinyl silicone oil and the hydrogen-containing silicone oil was 50 cps. The catalyst was a platinum catalyst.
[0034] Example 4 Example 4 provides a method for preparing a single-component curable 18W thermally conductive gel, comprising the following steps: 93g of vinyl silicone oil, 7g of hydrogen-containing silicone oil, and 3950g of hydroxyl silicone oil-modified aluminum nitride from Preparation Example 2 were kneaded at 90°C for 30 minutes, followed by the addition of 0.1g of catalyst to obtain a thermally conductive gel; wherein the viscosity of both vinyl silicone oil and hydrogen-containing silicone oil was 50 cps; and the catalyst was a platinum catalyst.
[0035] Example 5 Example 5 provides a method for preparing a single-component curable 18W thermally conductive gel, comprising the following steps: 97g of vinyl silicone oil, 3g of hydrogen-containing silicone oil, and 4050g of hydroxyl silicone oil-modified aluminum nitride from Preparation Example 2 were kneaded at 90°C for 30 minutes, followed by the addition of 0.3g of catalyst to obtain a thermally conductive gel. The viscosity of both the vinyl silicone oil and the hydrogen-containing silicone oil was 50 cps. The catalyst was a platinum catalyst.
[0036] Example 6 Example 6 provides a method for preparing a single-component curable 18W thermally conductive gel, comprising the following steps: 95g of vinyl silicone oil, 5g of hydrogen-containing silicone oil, and 4000g of hydroxyl silicone oil-modified aluminum nitride from Preparation Example 4 were kneaded at 90°C for 30 minutes, followed by the addition of 0.2g of catalyst to obtain a thermally conductive gel. The viscosity of both the vinyl silicone oil and the hydrogen-containing silicone oil was 50 cps. The catalyst was a platinum catalyst.
[0037] Example 7 Example 7 provides a method for preparing a single-component curable 18W thermally conductive gel, comprising the following steps: 95g of vinyl silicone oil, 5g of hydrogen-containing silicone oil, and 4000g of hydroxyl silicone oil-modified aluminum nitride from Preparation Example 5 were kneaded at 90°C for 30 minutes, followed by the addition of 0.2g of catalyst to obtain a thermally conductive gel. The viscosity of both the vinyl silicone oil and the hydrogen-containing silicone oil was 50 cps. The catalyst was a platinum catalyst.
[0038] Example 8 Example 8 provides a method for preparing a single-component curable 18W thermally conductive gel, comprising the following steps: 95g of vinyl silicone oil, 5g of hydrogen-containing silicone oil, and 4000g of hydroxyl silicone oil-modified aluminum nitride from Preparation Example 6 were kneaded at 90°C for 30 minutes, followed by the addition of 0.2g of catalyst to obtain a thermally conductive gel. The viscosity of both the vinyl silicone oil and the hydrogen-containing silicone oil was 50 cps. The catalyst was a platinum catalyst.
[0039] Example 9 Example 9 provides a method for preparing a single-component curable 18W thermally conductive gel, comprising the following steps: 95g of vinyl silicone oil, 5g of hydrogen-containing silicone oil, and 4000g of hydroxyl silicone oil-modified aluminum nitride from Preparation Example 7 were kneaded at 90°C for 30 minutes, followed by the addition of 0.2g of catalyst to obtain a thermally conductive gel. The viscosity of both the vinyl silicone oil and the hydrogen-containing silicone oil was 50 cps. The catalyst was a platinum catalyst.
[0040] Example 10 Example 10 provides a method for preparing a one-component curable 18W thermally conductive gel, comprising the following steps: 95g of vinyl silicone oil, 5g of hydrogen-containing silicone oil, 4000g of hydroxyl silicone oil-modified aluminum nitride from Preparation Example 2, and 20g of modified fumed silica from Preparation Example 8 were kneaded at 90°C for 30min, and then 0.2g of catalyst was added to obtain a thermally conductive gel; wherein the viscosity of both vinyl silicone oil and hydrogen-containing silicone oil was 50cps; and the catalyst was a platinum catalyst.
[0041] Example 11 Example 11 provides a method for preparing a one-component curable 18W thermally conductive gel, comprising the following steps: 95g of vinyl silicone oil, 5g of hydrogen-containing silicone oil, 4000g of hydroxyl silicone oil-modified aluminum nitride from Preparation Example 2, and 20g of modified fumed silica from Preparation Example 9 were kneaded at 90°C for 30 minutes, followed by the addition of 0.2g of catalyst to obtain a thermally conductive gel; wherein the viscosity of both vinyl silicone oil and hydrogen-containing silicone oil was 50 cps; and the catalyst was a platinum catalyst.
[0042] Example 12 Example 12 provides a method for preparing a single-component curable 18W thermally conductive gel, comprising the following steps: 95g of vinyl silicone oil, 5g of hydrogen-containing silicone oil, 4000g of hydroxyl silicone oil-modified aluminum nitride from Preparation Example 2, and 20g of modified fumed silica from Preparation Example 10 were kneaded at 90°C for 30min, followed by the addition of 0.2g of catalyst to obtain a thermally conductive gel; wherein the viscosity of both vinyl silicone oil and hydrogen-containing silicone oil was 50cps; and the catalyst was a platinum catalyst. Comparative Example
[0043] Comparative Example 1 Comparative Example 1 provides a method for preparing a one-component curable 18W thermally conductive gel, comprising the following steps: 95g of vinyl silicone oil, 5g of hydrogen-containing silicone oil, and 4000g of aluminum nitride were kneaded at 90℃ for 30min, followed by the addition of 0.2g of catalyst to obtain a thermally conductive gel. The viscosity of both the vinyl silicone oil and the hydrogen-containing silicone oil was 50cps. The catalyst was a platinum catalyst. The aluminum nitride was a mixture of aluminum nitride powder with a particle size of less than 1µm, aluminum nitride powder with a particle size of 5µm, and aluminum nitride powder with a particle size of 150µm, with a weight ratio of 800:1200:2000. Performance testing experiment
[0044] Performance testing: The thermal conductivity and extrusion rate of the gel in each example and comparative example were tested.
[0045] Table 1 Performance test results of thermally conductive gel
[0046] Combining Example 1 and Comparative Example 1, the gel in Example 1 exhibits both high thermal conductivity and high extrusion rate. This indicates that during gel preparation, the modification of aluminum nitride with hydroxyl silicone oil forms strong Si-O-Al covalent bonds, thereby transforming the hydrophilic / polar surface into a hydrophobic / oleophilic surface. The modified aluminum nitride powder exhibits significantly improved compatibility with silicone oil, resolving its dispersibility and interface issues in the polymer matrix and fully leveraging its thermal conductivity. The long chains of silicone oil molecules attached to the powder surface act as if the powder is dressed in an organic polymer "coat." When the powder particles approach each other, the organic polymer generates a steric hindrance effect, preventing direct contact between the powder particles and effectively preventing agglomeration. Furthermore, the resulting gel has a faster extrusion rate, facilitates dispensing, and exhibits high thermal conductivity.
[0047] In combination with Examples 1-3, the gel in Example 2 exhibits the best performance, indicating that the preparation conditions in Example 2 are optimal for preparing hydroxyl silicone oil-modified aluminum nitride.
[0048] Based on Examples 2, 4, and 5, it can be seen that when preparing the gel, following the raw material ratios in Examples 2, 4, and 5 yields a gel with better performance.
[0049] Combining Examples 2 and 6-9, the gel in Example 2 exhibits the best performance. This indicates that when preparing hydroxyl silicone oil-modified aluminum nitride, the optimal ratio of aluminum nitride powder with a particle size of less than 1 μm, aluminum nitride powder with a particle size of 5 μm, and aluminum nitride powder with a particle size of 150 μm is achieved in Example 2.
[0050] Combining Examples 2 and 10-12, the gel in Examples 10-12 exhibits better performance. This indicates that when preparing the gel, adding modified fumed silica to the raw materials creates a hydrophobic surface layer. This layer has excellent compatibility with hydroxyl silicone oil-modified aluminum nitride and can be uniformly interspersed among the fillers. Its hydrophobic surface has strong affinity with the silicone oil matrix, requiring less shear force for dispersion. This allows for faster formation of a uniform thixotropic structure, preventing the thermally conductive filler from settling and further improving the gel extrusion rate.
[0051] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.
Claims
1. A single-component, curable 18W thermally conductive gel, characterized in that: The thermally conductive gel comprises the following components in parts by weight: 93-97 parts vinyl silicone oil, 3-7 parts hydrogen-containing silicone oil, 3950-4050 parts hydroxyl silicone oil-modified aluminum nitride, and 0.1-0.3 parts catalyst.
2. The single-component curable 18W thermally conductive gel according to claim 1, characterized in that: The viscosity of both the vinyl silicone oil and the hydrogen-containing silicone oil is 50 cps.
3. The single-component curable 18W thermally conductive gel according to claim 1, characterized in that: The preparation method of the hydroxyl silicone oil modified aluminum nitride includes the following steps: Aluminum nitride powder was pre-dried at 110°C for 2 hours, then an organic solvent was added and the mixture was evenly dispersed. Hydroxy silicone oil was then added and the temperature was raised to 110°C. Subsequently, dibutyltin dilaurate was added to react the mixture, and the product was separated to obtain hydroxy silicone oil modified aluminum nitride.
4. The single-component curable 18W thermally conductive gel according to claim 3, characterized in that: The aluminum nitride powder comprises a mixture of aluminum nitride powder with a particle size of less than 1 μm, aluminum nitride powder with a particle size of 5 μm, and aluminum nitride powder with a particle size of 150 μm.
5. The single-component curable 18W thermally conductive gel according to claim 3, characterized in that: The weight ratio of the hydroxyl silicone oil to the aluminum nitride powder is (0.5-1.5):100; the weight ratio of the dibutyltin dilaurate to the hydroxyl silicone oil is (0.5-1.5):
100.
6. The single-component curable 18W thermally conductive gel according to claim 1, characterized in that: The catalyst includes a platinum catalyst.
7. The single-component curable 18W thermally conductive gel according to claim 1, characterized in that: The raw materials of the thermally conductive gel also include 10-30 parts by weight of modified fumed silica; The method for preparing the modified fumed silica includes the following steps: Hydrophilic fumed silica was dried at 120°C for 4 hours to obtain the dried material. The dried material was dispersed in anhydrous ethanol and ultrasonically dispersed to obtain a suspension. Hexamethyldisilazane was added dropwise at 60°C. After the addition was complete, the temperature was raised to 78°C and the reaction was continued at this temperature for 6 hours. After the reaction was completed, the mixture was cooled to room temperature, and the solid product was separated by filtration and washed with anhydrous ethanol. The washed solid product was dried at 80°C for 8 hours and then pulverized to obtain modified fumed silica.
8. The single-component curable 18W thermally conductive gel according to claim 7, characterized in that: The weight ratio of the hydrophilic fumed silica, the anhydrous ethanol, and the hexamethyldisilazane is 100:(390-400):(25-30).
9. A method for preparing a single-component curable 18W thermally conductive gel as described in any one of claims 1-8, characterized in that: Includes the following steps: Vinyl silicone oil, hydrogen-containing silicone oil, hydroxyl silicone oil-modified aluminum nitride, and other raw materials were kneaded at 90°C for 30 minutes, and then a catalyst was added to obtain a thermally conductive gel.