Low temperature triggered crosslinking pump-out resistant high thermal conductivity silicone thermal interface material and method of making

Abstract

This invention discloses a low-temperature triggered crosslinking, anti-pumping, high thermal conductivity organosilicon thermal interface material and its preparation method. By weight, it comprises the following components: 2-5.5 parts vinyl polysiloxane; 0.5-3 parts hydrogen-containing polysiloxane; 5-10 parts spherical alumina; 9-14 parts irregular aluminum nitride; 18-28.8 parts spherical aluminum nitride; 40.5-63 parts spherical aluminum nitride; 0.4-1.3 parts coupling agent; 0.005-0.1 parts inhibitor; and 0.0005-0.01 parts catalyst, wherein the Si–H / Vi molar ratio is 0.2-1.0. This application achieves differentiated physical states at different stages by controlling the ratio of inhibitor and catalyst, and the Si–H / Vi molar ratio, thus realizing interface wetting, structural locking, and fixed thermal conductivity pathways without increasing the sizing viscosity.

Description

Technical Field

[0001] This invention relates to the field of thermal interface materials technology, and in particular to a low-temperature triggered crosslinking anti-pumping high thermal conductivity organosilicon thermal interface material and its preparation method. Background Technology

[0002] With the rapid development of fields such as artificial intelligence, high-performance computing, and electric vehicles, the power density of electronic devices continues to increase, placing higher demands on the thermal conductivity and long-term reliability of thermal interface materials (TIMs). Existing thermal greases, due to their good workability and adaptability to minute gaps, are widely used in interface heat dissipation scenarios below 100 micrometers, especially suitable for brush-applied processes. These thermally conductive materials are typically non-reactive paste systems with low viscosity, enabling good interface wetting and filling after the heat dissipation structure is assembled. However, during long-term device operation, due to the difference in the coefficient of thermal expansion (CTE) between the chip, substrate, and heat sink, the interface undergoes periodic shear displacement under thermal cycling, coupled with thermal stress and mechanical disturbances, causing the internal structure of the material to gradually become unstable, resulting in a phenomenon of migration from the contact interface outwards, i.e., pump-out failure. After pump-out, dry spots and void areas form at the interface, leading to a significant increase in interface thermal resistance, a decrease in heat dissipation efficiency, and consequently affecting the temperature control, stability, and lifespan of electronic devices.

[0003] To address the pump-out problem, existing improvements mainly include increasing system viscosity, using silicone oils with special molecular structures, or improving the coating structure of thermally conductive powder surfaces. However, increasing system viscosity reduces the material's workability and brushing adaptability, while using silicone oils with special molecular structures or improving the coating structure of thermally conductive powder surfaces can lead to poor anti-pump-out performance, failing to meet industry requirements. The failure of thermally conductive interface materials in electronic devices is not simply due to insufficient thermal conductivity, but more so to the inability of the interface structure to maintain a stable morphology under long-term thermo-mechanical coupling. Existing technologies mostly address the issue by increasing material viscosity, introducing special silicone oil structures, or improving the coating structure of thermally conductive powder surfaces, but fundamentally fail to solve the structural problem of interface material migration due to shear displacement during service. Therefore, existing technologies still struggle to achieve an effective balance between workability, thermal conductivity, and anti-pump-out reliability. There is a need to develop novel thermal interface materials that can maintain fluid-like operability during the sizing stage and transform into a weak network system with elastic structural locking capability during service. This would allow for stable maintenance of interface wetting and thermal conduction pathways under thermal cycling and thermal stress environments, meeting the long-term heat dissipation reliability requirements of modern high-power electronic devices. Summary of the Invention

[0004] To address the aforementioned problems in the existing technology, this invention provides a low-temperature triggered crosslinking, anti-pumping, high thermal conductivity organosilicon thermal interface material.

[0005] Another objective of this invention is to provide a method for preparing a low-temperature triggered crosslinking anti-pumping, high thermal conductivity organosilicon thermal interface material.

[0006] To solve the above problems, the present invention adopts the following technical solution: a low-temperature triggered crosslinking anti-pumping high thermal conductivity organosilicon thermal interface material, comprising the following components by weight:

[0007] It contains 2-5.5 parts of vinyl polysiloxane; 0.5-3 parts of hydrogen-containing polysiloxane; 5-10 parts of spherical alumina; 9-14 parts of irregular aluminum nitride; 18-28.8 parts of spherical aluminum nitride; 40.5-63 parts of spherical aluminum nitride; 0.4-1.3 parts of coupling agent; 0.005-0.1 parts of inhibitor; and 0.0005-0.01 parts of catalyst, wherein the Si–H / Vi molar ratio is 0.2-1.0.

[0008] Furthermore, the inhibitor is one or more of 3-methyl-1-butyn-3-ol, 2-methyl-3-butyn-2-ol, 1-ethynyl-1-cyclohexanol, and 3,5-dimethyl-1-hexyn-3-ol in any proportion.

[0009] Furthermore, the catalyst is a platinum catalyst.

[0010] Furthermore, the spherical alumina, irregular aluminum nitride, near-spherical aluminum nitride, and spherical aluminum nitride are surface-treated thermally conductive fillers.

[0011] This application also provides a method for preparing the aforementioned low-temperature triggered crosslinking, anti-pumping, high thermal conductivity organosilicon thermal interface material, the method comprising the following steps:

[0012] Step 1: Add vinyl silicone oil, hydrogen-containing methyl silicone oil, spherical alumina, irregular alumina, near-spherical aluminum nitride, and spherical aluminum nitride to a planetary disperser. Stir at 25 rpm for 50 min under normal pressure.

[0013] Step 2: Continue stirring for 25 minutes under a vacuum of less than -0.9 kPa;

[0014] Step 3: Add the inhibitor, stir at a temperature below 25°C, at a stirring speed of 15 rpm, and at normal pressure for 10 minutes.

[0015] Step 4: Add platinum catalyst, stir at a temperature below 25°C and a stirring speed of 15 rpm, and mix for 10 min under a vacuum of less than -0.9 kPa to form the thermal interface material.

[0016] Furthermore, the surface treatment method for the thermally conductive powder includes the following steps: wherein

[0017] S1. Take a straight-chain or branched alkane-based silane coupling agent with three or more carbon atoms as the characteristic functional group and prepare it into a homogeneous solution, and divide it into two equal portions.

[0018] S2. Gradually disperse the first portion of silane solution onto the surface of the thermally conductive powder;

[0019] S3, Simultaneously with S2, after the first silane solution is added, react at 50-70℃ for 2-4 hours;

[0020] S4. Add the second part of silane solution and react at 80-90℃ for 4-6 h.

[0021] S5. After the reaction is complete, the powder is baked at 110-130℃ for 1.5-2.5 h to obtain the treated thermally conductive fraction.

[0022] Furthermore, the thermally conductive material adopts a four-stage high-filling strategy, and is compounded in the following proportions:

[0023] Spherical alumina, as a fine filler component, has an average particle size of 0.3-1.0 micrometers and is added at a rate of 6%-10%.

[0024] Irregular aluminum nitride, with an average particle size of 0.5-1.5 micrometers, is added at a rate of 10%-15%.

[0025] Spherical aluminum nitride with an average particle size of 3-8 micrometers, added at a rate of 20%-30%;

[0026] Spherical aluminum nitride with an average particle size of 20,440 micrometers, with an addition ratio of 45%-665%;

[0027] The maximum particle size of the powder is less than 40 micrometers.

[0028] The thermal interface material is stored in an environment below 10°C.

[0029] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0030] 1. The low-temperature triggered crosslinking anti-pumping high thermal conductivity organosilicon thermal interface material provided in this application enables the material to have differentiated physical states at different stages by controlling the ratio of inhibitors and catalysts and the molar ratio of Si–H / Vi. During the construction stage, it maintains low shear resistance and good wetting ability to adapt to micro-gap filling and brushing processes. After the device is heated and enters the service state, the material can undergo a controllable structural transformation to form a weak network skeleton with elastic constraint capabilities. This transforms the interfacial shear displacement from the overall flow of the material to the elastic deformation absorption of the weak network, thereby achieving interfacial wetting and structural locking, and fixing of thermal conductivity pathways without increasing the sizing viscosity.

[0031] 2. This application constructs a low-temperature (50~80℃) cross-linkable organosilicon matrix system, a gradient particle size thermally conductive filler skeleton, and a powder surface structure with interface energy control, so that the thermally conductive filler network is locked in the elastic siloxane weak network during the service stage, thereby maintaining a stable heat transfer structure under cold and hot cycling and thermal stress environment, and achieving a synergistic unity of anti-pumping, high thermal conductivity and good workability. Attached Figure Description

[0032] Figure 1 This is a schematic diagram illustrating the application of the thermal interface material described in the embodiments of this patent application;

[0033] Among them, 1. substrate, 2. chip, 3. heat spreader, 4. thermal interface material, and 5. heat sink. Detailed Implementation

[0034] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "vertical," "horizontal," and "inner," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0036] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0037] Example

[0038] This invention provides a low-temperature curable, pump-out resistant, and highly thermally conductive organosilicon thermal interface material, comprising 2-5.5 parts of vinyl polysiloxane; 0.5-3 parts of hydrogen-containing polysiloxane; 5-10 parts of spherical alumina; 9-14 parts of irregular aluminum nitride; 18-28.8 parts of spherical aluminum nitride; 40.5-63 parts of spherical aluminum nitride; 0.4-1.3 parts of coupling agent; 0.005-0.1 parts of inhibitor; and 0.0005-0.01 parts of catalyst, wherein the Si–H / Vi molar ratio is 0.2-1.0. It should be noted that the spherical alumina, irregular aluminum nitride, spherical aluminum nitride, and spherical aluminum nitride are surface-treated thermally conductive fillers.

[0039] The inhibitor is one or more of 3-methyl-1-butyn-3-ol, 2-methyl-3-butyn-2-ol, 1-ethynyl-1-cyclohexanol, and 3,5-dimethyl-1-hexyn-3-ol in any proportion.

[0040] In some preferred embodiments, the catalyst is a platinum catalyst.

[0041] Example 1

[0042] The low-temperature crosslinked, anti-pumping, high thermal conductivity organosilicon thermal interface material described in this application is prepared using raw materials and reference weight parts as shown in Formulation Table 1.

[0043] The thermally conductive filler in the thermal interface material is surface-treated alumina and aluminum nitride powder, with the following particle size and weight ratio: spherical alumina with D50 of 0.5 μm and D100 ≤ 40 μm; irregular aluminum nitride with D50 of 0.8 μm and D100 ≤ 40 μm; near-spherical aluminum nitride with D50 of 3 μm and D100 ≤ 40 μm; and spherical aluminum nitride with D50 of 25 μm and D100 ≤ 40 μm.

[0044] The components are present in a weight ratio of 0.5μm : 0.8μm : 3μm : 25μm = 0.4 : 0.6 : 2 : 3.5.

[0045] The specific surface treatment method for thermally conductive powder is as follows:

[0046] S1. Weigh an appropriate amount of octyltrimethoxysilane, prepare it into a homogeneous solution, and divide it into two equal portions.

[0047] S2. Gradually disperse the first portion of octyltrimethoxysilane solution onto the surface of the thermally conductive powder. The amount of coupling agent, based on the powder weight, is as follows: 1.2% for spherical alumina with D50 of 0.5 μm and D100 ≤ 40 μm; 1.6% for irregular aluminum nitride with D50 of 0.8 μm and D100 ≤ 40 μm; 1.0% for near-spherical aluminum nitride with D50 of 3 μm and D100 ≤ 40 μm; and 0.5% for spherical aluminum nitride with D50 of 25 μm and D100 ≤ 40 μm.

[0048] S3, Simultaneously with S2, after the first octyltrimethoxysilane solution is added, the reaction is carried out at 60°C for 3 h;

[0049] S4. After adding the second portion of octyltrimethoxysilane solution, react at 85°C for 5 hours.

[0050] S5. After the reaction is complete, bake the powder at 120℃ for 2 hours and set aside.

[0051] This application provides a method for preparing a low-temperature crosslinked, anti-pumping, high thermal conductivity organosilicon thermal interface material, wherein the material temperature is controlled below 30°C during stirring, and the specific steps include:

[0052] Step 1: Add the materials from Formulation Table 1 to the planetary disperser, including 5.5 parts vinyl silicone oil, 2.5 parts hydrogen-containing methyl silicone oil, 8 parts spherical alumina, 16 parts irregular aluminum nitride, 40 parts near-spherical aluminum nitride, and 70 parts spherical aluminum nitride. The stirring speed is 25 rpm, and the mixing time under normal pressure is 50 min.

[0053] Step 2: Stir the material described in Step 1 for 25 minutes under a vacuum of less than -0.9 kPa.

[0054] Step 3: After the mixing in Step 2 is completed, add 3,6-dimethyl-1-heptyne-3-ol, control the material temperature below 25℃, set the stirring speed to 15 rpm, and mix for 10 min under normal pressure.

[0055] Step 4: Add the platinum catalyst, control the material temperature below 25°C, set the stirring speed to 15 rpm, and mix and stir for 10 min under a vacuum of less than -0.9 kPa to obtain the organosilicon thermal interface material described in this application. The material needs to be stored in an environment below 10°C.

[0056] like Figure 1 As shown, the silicone thermal interface material described in this embodiment is applied to the chip 2. Specifically, the chip 2 is disposed on the substrate 1, and a heat spreader 3 is disposed on the chip 2. The silicone thermal interface material 4 described in this application is disposed between the heat spreader 3 and the heat sink 5.

[0057]

[0058] Example 2

[0059] This invention provides a low-temperature curable, pump-out resistant silicone thermal interface material, the raw materials and reference weight parts of which are shown in Formulation Table 2. The thermally conductive filler of the thermal interface material is surface-treated alumina and aluminum nitride powder, with the following particle size and weight ratio: spherical alumina with D50 of 0.5 μm and D100 ≤ 40 μm; irregular aluminum nitride with D50 of 0.8 μm and D100 ≤ 40 μm; spherical alumina with D50 of 3 μm and D100 ≤ 40 μm; and spherical alumina with D50 of 25 μm and D100 ≤ 40 μm. The weight ratio of each component is 0.5 μm : 0.8 μm : 3 μm : 25 μm = 0.4 : 0.6 : 2 : 3.5. Figure 1 As shown, the silicone thermal interface material described in this embodiment is applied to the chip 2. Specifically, the chip 2 is disposed on the substrate 1, and a heat spreader 3 is disposed on the chip 2. The silicone thermal interface material 4 described in this application is disposed between the heat spreader 3 and the heat sink 5.

[0060] The surface treatment method for thermally conductive powder described in this embodiment is as follows:

[0061] S1. Weigh an appropriate amount of octyltrimethoxysilane, prepare it into a homogeneous solution, and divide it into two equal portions.

[0062] S2. Gradually disperse the first portion of octyltrimethoxysilane solution onto the surface of the thermally conductive powder. The amount of coupling agent, based on the powder weight, is as follows: 1.2% for spherical alumina with D50 of 0.5 μm and D100 ≤ 40 μm; 1.6% for irregular aluminum nitride with D50 of 0.8 μm and D100 ≤ 40 μm; 1.0% for spherical alumina with D50 of 3 μm and D100 ≤ 40 μm; and 0.5% for spherical alumina with D50 of 25 μm and D100 ≤ 40 μm.

[0063] S3, Simultaneously with S2, after the first octyltrimethoxysilane solution is added, the reaction is carried out at 60°C for 3 h;

[0064] S4. After adding the second portion of octyltrimethoxysilane solution, react at 85°C for 5 hours.

[0065] S5. After the reaction is complete, bake the powder at 120℃ for 2 hours and set aside.

[0066] This application provides a method for preparing a low-temperature crosslinked, anti-pumping, high thermal conductivity organosilicon thermal interface material, wherein the material temperature is controlled below 25°C during stirring, and the specific steps include:

[0067] Step 1: Add the materials from Formulation Table 1 to the planetary disperser, including 5.5 parts vinyl silicone oil, 2.5 parts hydrogen-containing methyl silicone oil, 8 parts spherical alumina, 16 parts irregular aluminum nitride, 40 parts near-spherical aluminum nitride, and 70 parts spherical aluminum nitride. The stirring speed is 25 rpm, and the mixing time under normal pressure is 50 min.

[0068] Step 2: Stir the material described in Step 1 for 25 minutes under a vacuum of less than -0.9 kPa.

[0069] Step 3: After the mixing in Step 2 is completed, add 3,6-dimethyl-1-heptyne-3-ol, control the material temperature below 25℃, set the stirring speed to 15 rpm, and mix for 10 min under normal pressure.

[0070] Step 4: Add the platinum catalyst, control the material temperature below 25°C, set the stirring speed to 15 rpm, and mix and stir for 10 min under a vacuum of less than -0.9 kPa to obtain the organosilicon thermal interface material described in this application. The material needs to be stored in an environment below 10°C.

[0071] Table 2

[0072] Comparative Example 1

[0073] Comparative Example 1 provides a low-temperature curable organosilicon thermal interface material, the raw materials used in its preparation and the reference weight parts are shown in Formulation Table 3.

[0074] The thermal interface material's thermally conductive filler is alumina and aluminum nitride powder, with the following particle size and weight ratio: D50 is 0.5μm spherical alumina; D50 is 0.8μm irregular aluminum nitride; D50 is 3μm near-spherical aluminum nitride; D50 is 25μm spherical aluminum nitride; wherein the weight ratio of each component is 0.5μm : 0.8μm : 3μm : 25μm = 0.4 : 0.6 : 2 : 3.5.

[0075] The preparation method of the low-temperature curable organosilicon thermal interface material (the material temperature needs to be controlled below 30°C during stirring) includes the following steps:

[0076] Step 1: In a planetary disperser, add the following materials in formula table 1 in sequence: vinyl silicone oil, hydrogen-containing methyl silicone oil, spherical alumina, irregular aluminum nitride, near-spherical aluminum nitride, and spherical aluminum nitride. Mix at 25 rpm under normal pressure for 50 min.

[0077] Step 2: Continue stirring for 25 minutes under a vacuum of less than -0.9 kPa;

[0078] Step 3: Add 3,6-dimethyl-1-heptyne-3-ol and mix at 15 rpm under normal pressure for 10 min.

[0079] Step 4: Add the platinum catalyst and mix at a stirring speed of 15 rpm under a vacuum of less than -0.9 kPa for 10 minutes to obtain the organosilicon thermal interface material described in this embodiment. The material needs to be stored in an environment below 10°C.

[0080] Comparative Example 2

[0081] A non-reactive thermal grease is provided, and the raw materials and reference weight parts used in its preparation are shown in Formulation Table 4.

[0082] The thermally conductive filler of the thermal interface material is surface-treated alumina and aluminum nitride powder, with the following particle size and weight ratio: spherical alumina with D50 of 0.5 μm and D100 ≤ 40 μm; irregular aluminum nitride with D50 of 0.8 μm and D100 ≤ 40 μm; near-spherical aluminum nitride with D50 of 3 μm and D100 ≤ 40 μm; and spherical aluminum nitride with D50 of 25 μm and D100 ≤ 40 μm. The weight ratio of each component is 0.5 μm : 0.8 μm : 3 μm : 25 μm = 0.4 : 0.6 : 2 : 3.5.

[0083] A method for surface treatment of thermally conductive powder, including the following steps

[0084] S1. Weigh an appropriate amount of octyltrimethoxysilane, prepare it into a homogeneous solution, and divide it into two equal portions.

[0085] S2. Gradually disperse the first portion of octyltrimethoxysilane solution onto the surface of the thermally conductive powder. The amount of coupling agent, based on the powder weight, is as follows: Spherical alumina with D50 of 0.5 μm and D100 ≤ 40 μm: 1.2%; Irregular aluminum nitride with D50 of 0.8 μm and D100 ≤ 40 μm: 1.6%; Quasi-spherical aluminum nitride with D50 of 3 μm and D100 ≤ 40 μm: 1.0%; Spherical aluminum nitride with D50 of 25 μm and D100 ≤ 40 μm: 0.5%.

[0086] S3. After the first octyltrimethoxysilane solution is added, the reaction is carried out at 60°C for 3 h.

[0087] S4. After adding the second portion of octyltrimethoxysilane solution, react at 85°C for 5 hours.

[0088] S5. After the reaction is complete, bake the powder at 120℃ for 2 hours and set aside.

[0089] The preparation method of the non-reactive thermal grease:

[0090] Step 1: Add the materials listed in Formulation Table 4 in sequence to the planetary disperser: methyl silicone oil, spherical alumina, irregular aluminum nitride, and near-spherical aluminum nitride. Mix at 25 rpm under normal pressure for 50 min.

[0091] Step 2: Continue stirring for 25 minutes under a vacuum of less than -0.9 kPa to obtain the material.

[0092]

[0093] The silicone thermal interface material samples obtained in Examples 1-2 and Comparative Examples 1-2 were tested for thermal conductivity, thermal resistance, viscosity, minimum gap thickness, pump-out resistance, aging resistance, and processability. The evaluation results are as follows:

[0094] Thermal conductivity test: The silicone thermal interface materials obtained in Examples 1-2 and Comparative Examples 1-2 were tested using a thermal conductivity tester (ASTM D5470) at 80°C, and the thermal conductivity was obtained by fitting the materials at three points of 0.5 mm, 1.0 mm and 1.5 mm.

[0095] Thermal resistance test: The silicone thermal interface materials obtained in Examples 1-2 and Comparative Examples 1-2 were tested using a thermal conductivity tester (ASTM D5470) at 80°C and 20 PSI.

[0096] Viscosity test: The silicone thermal interface materials obtained in Examples 1-2 and Comparative Examples 1-2 were tested by rheometer at a shear rate of 10 s-1 before and after curing at 25°C.

[0097] Minimum gap-filling thickness test: The minimum compressible thickness of the organosilicon thermal interface materials obtained in Examples 1-2 and Comparative Examples 1-2 at 20 PSI was tested respectively.

[0098] Pump-out resistance test: The silicone thermal interface materials obtained in Examples 1-2 and Comparative Examples 1-2 were assembled on IGBT modules respectively. The contact pressure was fixed at 30 PSI. Then, the IGBT modules were placed in a thermal cycling chamber ranging from −40℃ to 125℃ (the heating and cooling stages and the high and low temperature holding stages were all set to 15 min, and the total cycle time was 60 min) for 1000 cycles. After 1000 cycles, the void area was calculated after opening the IGBT modules to evaluate the degree to which the material was squeezed out of the interface under thermal expansion and contraction.

[0099] Aging resistance test: The organosilicon thermal interface materials obtained in Examples 1-2 and Comparative Examples 1-2 were placed in a high-temperature environment of 150°C for 1000 hours for continuous aging. The stability under long-term high-temperature environment was evaluated by comparing whether hardening and powdering occurred after aging.

[0100] Processability test: The silicone thermal interface materials obtained in Examples 1-2 and Comparative Examples 1-2 were uniformly brushed onto the surface of a glass substrate to a thickness of 100 μm under standard conditions. The spreadability, stringiness and coating uniformity during the construction process were observed to determine whether the material has both good workability and film formation consistency.

[0101]

[0102] Finally, it should be pointed out that the above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A low-temperature triggered crosslinking, anti-pumping, high thermal conductivity organosilicon thermal interface material, characterized in that, Based on parts by weight, it includes the following components: It contains 2-5.5 parts of vinyl polysiloxane; 0.5-3 parts of hydrogen-containing polysiloxane; 5-10 parts of spherical alumina; 9-14 parts of irregular aluminum nitride; 18-28.8 parts of spherical aluminum nitride; 40.5-63 parts of spherical aluminum nitride; 0.4-1.3 parts of coupling agent; 0.005-0.1 parts of inhibitor; and 0.0005-0.01 parts of catalyst, wherein the Si–H / Vi molar ratio is 0.2-1.

0.

2. The low-temperature triggered crosslinking anti-pumping high thermal conductivity organosilicon thermal interface material according to claim 1, characterized in that, The inhibitor is one or more of 3-methyl-1-butyn-3-ol, 2-methyl-3-butyn-2-ol, 1-ethynyl-1-cyclohexanol, and 3,5-dimethyl-1-hexyn-3-ol in any proportion.

3. The low-temperature triggered crosslinking anti-pumping high thermal conductivity organosilicon thermal interface material according to claim 1, characterized in that, The catalyst is a platinum catalyst.

4. The low-temperature triggered crosslinking anti-pumping high thermal conductivity organosilicon thermal interface material according to claim 1, characterized in that, The spherical alumina, irregular nitride, spherical aluminum nitride, and spherical aluminum nitride are surface-treated thermally conductive fillers.

5. A method for preparing a low-temperature triggered crosslinking, anti-pumping, high thermal conductivity organosilicon thermal interface material as described in claim 1, characterized in that, The method includes the following steps: Step 1: Add vinyl silicone oil, hydrogen-containing methyl silicone oil, spherical alumina, irregular alumina, near-spherical aluminum nitride, and spherical aluminum nitride to a planetary disperser. Stir at 25 rpm for 50 min under normal pressure. Step 2: Continue stirring for 25 minutes under a vacuum of less than -0.9 kPa; Step 3: Add the inhibitor, stir at a temperature below 25°C, stir at a speed of 15 rpm, and stir for 10 minutes under normal pressure. Step 4: Add platinum catalyst, stir at a temperature below 25°C and a stirring speed of 15 rpm, and mix for 10 min under a vacuum of less than -0.9 kPa to form the thermal interface material.

6. The method for preparing the low-temperature triggered crosslinking anti-pumping high thermal conductivity organosilicon thermal interface material according to claim 5, characterized in that, The surface treatment method for thermally conductive powder includes the following steps: wherein S1. Take a straight-chain or branched alkane-based silane coupling agent with three or more carbon atoms as the characteristic functional group and prepare it into a homogeneous solution, and divide it into two equal portions. S2. Gradually disperse the first portion of silane solution onto the surface of the thermally conductive powder; S3, Simultaneously with S2, after the first silane solution is added, react at 50-70℃ for 2-4 hours; S4. Add the second part of silane solution and react at 80-90℃ for 4-6 h. S5. After the reaction is complete, the powder is baked at 110-130℃ for 1.5-2.5 h to obtain the treated thermally conductive powder.

7. The method for preparing the low-temperature triggered crosslinking anti-pumping high thermal conductivity organosilicon thermal interface material according to claim 6, characterized in that, The thermally conductive material adopts a four-stage high-filling strategy and is compounded in the following proportions: Spherical alumina, as a fine filler component, has an average particle size of 0.3-1.0 micrometers and is added at a rate of 6%-10%. Irregular aluminum nitride, with an average particle size of 0.5-1.5 micrometers, is added at a rate of 10%-15%. Spherical aluminum nitride with an average particle size of 3-8 micrometers, added at a rate of 20%-30%; Spherical aluminum nitride with an average particle size of 20-40 micrometers, and an addition ratio of 45%-65%; The maximum particle size of the powder is less than 40 micrometers.

8. The method for preparing the low-temperature triggered crosslinking anti-pumping high thermal conductivity organosilicon thermal interface material according to claim 5, characterized in that, The thermal interface material is stored in an environment below 10°C.

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