High-thermal-conductivity, high-temperature-aging-resistant thermal conductive gel and preparation method thereof

Abstract

The present application relates to a kind of high thermal conductivity, high-temperature aging-resistant heat-conducting gel and preparation method, the heat-conducting gel is two-component gel, including A component and B component, wherein, A component includes vinyl silicone oil, heat-conducting powder, surface modifier, anti-aging auxiliary agent, catalyst;B component includes vinyl silicone oil, heat-conducting powder, surface modifier, hydrogen-containing silicone oil, inhibitor;Wherein the heat-conducting powder is one or more of aluminium oxide, silicon powder, magnesium oxide, zinc oxide, aluminum nitride, silicon nitride, carbon nanotube (CNTs);The particle size of heat-conducting powder is ≤40 μm.The heat-conducting gel improves the thixotropy of product while ensuring the high thermal conductivity of product, improves the construction of product.It has the advantages such as low system viscosity, aging stability at high temperature, is suitable for the application scene of higher heat dissipation requirement and aging stability requirement, can significantly improve the heat dissipation effect.

Description

Technical Field

[0001] This invention relates to a thermally conductive gel with high thermal conductivity and resistance to high-temperature aging, belonging to the field of organosilicon thermally conductive gels. Background Technology

[0002] With increasingly demanding performance requirements for high-performance electronic devices, the high packaging and high power density of modern electronic components inevitably lead to thermal failures. Effective heat dissipation has become a key technology affecting the lifespan and performance of electronic devices. Thermal interface materials are the best choice to help solve heat dissipation problems. Thermal interface materials come in various forms, including thermally conductive gels, thermally conductive pads, thermally conductive pastes, and thermally conductive phase change materials. Thermally conductive gels, which are curable thermally conductive pastes and dispensable thermally conductive pads, have advantages such as ease of handling and low interfacial thermal resistance. They are considered to meet the future development needs of thermal interface materials and have received widespread attention from industries both domestically and internationally.

[0003] Compared to thermal conductive gel, thermal conductive pads are cured adhesive sheets that form thermal channels through compression between the heating and cooling components. However, due to the weak adhesion between the pads and the surface of the heating device, the contact thermal resistance increases, resulting in poorer thermal conductivity for the same thermal conductivity. Thermal conductive paste, on the other hand, is a non-curing paste-like thermal conductive material. During use, the silicone oil continuously evaporates, eventually leading to powdering. Thermally conductive phase change materials exhibit a certain degree of fluidity at high temperatures, causing them to overflow at the edges and affecting thermal conductivity.

[0004] Therefore, it is essential to develop thermally conductive gels with high thermal conductivity and resistance to high-temperature aging. Patent CN201710619110.6 proposes a two-component thermally conductive gel and its preparation method, but the colloid has low thixotropy and flowability, which is not conducive to in-situ curing after dispensing. Patent CN 202010151850.7 proposes a curable two-component thermally conductive and heat-storing silicone gel, which has a certain heat storage capacity at high temperatures, but after prolonged use in high-temperature environments, it inevitably experiences aging and hardness creep. Summary of the Invention

[0005] This invention addresses the current demand for high thermal conductivity in automotive, electronic components, and other electronic devices by developing a high thermal conductivity, high-temperature aging resistant thermal gel and its preparation method. While ensuring high thermal conductivity, it improves the product's thixotropic properties and workability. It features low system viscosity and high-temperature aging stability. This thermal gel is suitable for applications with high requirements for heat dissipation and aging stability, and can significantly improve heat dissipation performance.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] In the first aspect, the present invention provides a thermally conductive gel with high thermal conductivity and resistance to high temperature aging, comprising component A and component B, wherein the mass ratio of component A to component B is 1:0.5 to 2, for example 1:0.5, 1:0.7, 1:1, 1:1.2, 1:1.5, 1:1.8, 1:2, etc.;

[0008] Based on the total weight of component A, it contains the following components by weight percentage:

[0009] Vinyl silicone oil 2-10%, such as 2%, 4%, 6%, 8%, 10%, etc.

[0010] Polyether-modified silicone oil, 0.5-2%, such as 0.5%, 0.8%, 1%, 1.2%, 1.5%, 1.8%, 2%, etc.

[0011] Thermal conductive powder content 80-95%, such as 80%, 82%, 85%, 88%, 90%, 92%, 95%, etc.

[0012] Surface modifier 0.5-2%, such as 0.5%, 0.8%, 1%, 1.2%, 1.5%, 1.8%, 2%, etc.

[0013] Anti-aging additives at 0.2-1%, such as 0.2%, 0.4%, 0.6%, 0.8%, 1%, etc.

[0014] Catalyst 0.5-3%, for example 0.5%, 1%, 2%, 3%, etc.

[0015] Based on the total weight of component B, it contains the following components by weight percentage:

[0016] Vinyl silicone oil 2-10%, such as 2%, 4%, 6%, 8%, 10%, etc.

[0017] Thermal conductive powder content 80-95%, such as 80%, 82%, 85%, 88%, 90%, 92%, 95%, etc.

[0018] Surface modifier 0.5-2%, such as 0.5%, 0.8%, 1%, 1.2%, 1.5%, 1.8%, 2%, etc.

[0019] Hydrogen-containing silicone oil 5-10%, such as 5%, 6%, 7%, 8%, 9%, 10%, etc.

[0020] Inhibitors at concentrations of 0.2-1%, such as 0.2%, 0.5%, 0.8%, 1%, etc.

[0021] The thermally conductive powder is one or more of alumina, silicon micropowder, magnesium oxide, zinc oxide, aluminum nitride, silicon nitride, and carbon nanotubes (CNTs); the particle size of the thermally conductive powder is ≤40μm, for example, 0.1μm, 0.5μm, 1μm, 3μm, 5μm, 8μm, 10μm, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm, etc.; specifically, the thermally conductive powder in component A and component B can be the same or different.

[0022] In one specific embodiment, the viscosity of the vinyl silicone oil is 50-500 cP, for example 50 cP, 100 cP, 150 cP, 200 cP, 250 cP, 300 cP, 350 cP, 400 cP, 450 cP, 500 cP, etc.; specifically, the vinyl silicone oil in component A and component B may be the same or different.

[0023] For example, the vinyl silicone oil can be QL-2311VDV50 (50cP), QL-2311VDV100 (100cP), QL-200DM200 (250cP), or QL-200DM500 (500cP), manufactured by Huangshan Qiangli Chemical Co., Ltd.

[0024] In one specific embodiment, the viscosity of the polyether-modified silicone oil is 20-300 cP, such as 20 cP, 50 cP, 100 cP, 150 cP, 200 cP, 250 cP, 300 cP, etc.

[0025] For example, the polyether-modified silicone oil can be SYLGARD. TM OFX-0309(20cP), DOWSIL TM 5562 (50cP), XIAMETER TM OFX-5098 (250cP), DOWSIL TM 5604 (300cP), DOWSIL TM .

[0026] The polyether-modified silicone oil described in this invention is used as a surfactant to uniformly disperse the anti-aging additives in the silicone oil system.

[0027] In one specific embodiment, the particle shape of the thermally conductive powder can be spherical, near-spherical, plate-shaped, needle-shaped, or angular, with spherical particles being preferred;

[0028] As one preferred embodiment, the thermally conductive powder is a combination powder of zinc oxide and aluminum oxide; preferably, the mass ratio of zinc oxide to aluminum oxide is 1:(2-10), for example, 1:2, 1:4, 1:6, 1:8, 1:10, etc.; preferably, the particle size of the zinc oxide is ≤1μm.

[0029] As one preferred embodiment, the thermally conductive powder is a compound of at least one of alumina with a particle size of 1-5 μm and at least one of alumina with a particle size of 10-40 μm, and the mass ratio of the two compounded is 1:(1-5).

[0030] The thermally conductive powder described in this invention is used to improve the thixotropic properties of the product and alleviate the problem of adhesive overflow at the interface during curing. When using a zinc oxide-zinc oxide blend, this effect is more pronounced due to the surface effect of zinc oxide, significantly improving the product's thixotropic properties and application performance. Furthermore, using a blend of alumina particles with different sizes can further enhance the product's thermal conductivity.

[0031] In one specific embodiment, the surface modifier is one or more of aluminate coupling agents, silane coupling agents, titanate coupling agents, aluminum-titanium coupling agents, and organoboronate coupling agents, preferably one or more of aluminate coupling agents; specifically, the surface modifiers in component A and component B may be the same or different;

[0032] For example, the surface modifier can be HY-985 (aluminate coupling agent), KH-570 (silane coupling agent), HY-105 (phthalate coupling agent), or HY-133 (aluminum-titanium coupling agent), manufactured by Hangzhou Jessica Chemical Co., Ltd.

[0033] The surface modifier described in this invention has the effect of surface treatment of thermal conductive powder and activation of surfactant, improving the compatibility and dispersibility of thermal conductive powder such as alumina in silicone oil, so that the thermal conductive powder can be dispersed evenly. In particular, when an aluminate coupling agent is selected, it can effectively reduce the viscosity of the system and solve the structural problems during storage.

[0034] In one specific embodiment, the anti-aging agent is a ketone agent selected from one or more of chalcone, acetoin, raspberry ketone, p-methylacetophenone, and p-methylacetone, with chalcone being preferred.

[0035] The anti-aging additive described in this invention primarily functions to react with the remaining silane groups in the binding system at high temperatures, preventing further cross-linking with the vinyl groups in the system. This results in a continuous increase in hardness after the gel initially cures, improving the product's stability during high-temperature aging. When ketones containing phenyl chalcone or similar compounds are selected, their reaction with the remaining silane groups can effectively improve the resin's heat resistance, enhance the gel's aging stability at high temperatures, and mitigate the problem of hardening due to high-temperature aging.

[0036] In one specific embodiment, the catalyst is selected from one or more of platinum compounds and their complexes, palladium compounds and their complexes, nickel compounds and their complexes, and rhodium compounds and their complexes, preferably platinum compounds and their complexes;

[0037] For example, the catalyst can be CSAT-F1 (divinyltetramethyldisiloxane platinum complex) or CSAT-F6 (tetravinylcyclotetrasiloxane platinum complex), manufactured by Suzhou Betterley Polymer Materials Co., Ltd.

[0038] In one specific embodiment, the viscosity of the hydrogen-containing silicone oil is 10 to 500 cP, for example, 10 cP, 50 cP, 100 cP, 150 cP, 200 cP, 250 cP, 300 cP, 350 cP, 400 cP, 450 cP, 500 cP, etc.

[0039] As one preferred embodiment, the hydrogen-containing silicone oil is one or more of the following: end-containing hydrogen-containing silicone oil with a viscosity of 10-50 cP and side-containing hydrogen-containing silicone oil with a viscosity of 10-500 cP.

[0040] For example, the hydrogen-containing silicone oil can be CX-350 (10cP end hydrogen-containing silicone oil), CX-350LV (50cP end hydrogen-containing silicone oil), CX-351 (10cP side hydrogen-containing silicone oil), CX-351D (200cP side hydrogen-containing silicone oil), or CX-351HLV (500cP side hydrogen-containing silicone oil), manufactured by Guangzhou Chenxi New Materials Technology Co., Ltd.

[0041] In one specific embodiment, the inhibitor is one or more of tetramethyltetravinylcyclotetrasiloxane, methylbutynol, ethynylcyclohexanol, tetramethyldivinyldisiloxane, and phenylacetylene.

[0042] Secondly, the present invention provides a method for preparing the above-mentioned high thermal conductivity and high temperature aging resistant thermal conductive gel, which can be prepared by conventional blending methods in the field. Specifically, it includes the steps of mixing the raw materials of component A to obtain component A and mixing the raw materials of component B to obtain component B.

[0043] In one specific embodiment, a method for preparing a high thermal conductivity, high-temperature aging resistant thermal conductive gel includes the following steps:

[0044] (1) Add vinyl silicone oil, polyether modified silicone oil and thermal conductive powder to a mixing tank and stir. Then add surface modifier and heat to 100-120°C, keep warm and stir under vacuum. Then cool down to below 40°C, add anti-aging additive and catalyst, stir under vacuum, and filter to obtain component A.

[0045] (2) Add vinyl silicone oil and thermal conductive powder to a mixing tank and stir. Then add surface modifier and heat to 100-120°C, keep warm and stir under vacuum. Then cool down to below 40°C, add hydrogen-containing silicone oil and inhibitor, stir under vacuum, and filter to obtain component B.

[0046] Apart from the conditions specified in the above-mentioned operation steps, other related operations and process conditions in the preparation method of the present invention, such as the rotation speed and time used in the stirring process, the vacuum pressure, and the devices used, can all be carried out using the corresponding conventional selections in the field. Those skilled in the art can optimize the process based on existing technology and known processes according to actual needs, and there are no special restrictions on this.

[0047] The A component prepared in step (1) and the B component prepared in step (2) are respectively packaged into tubes and sealed for storage, which is the thermally conductive gel with high thermal conductivity and high temperature aging resistance of the present invention.

[0048] The thermally conductive gel described in this invention is suitable for applications with high requirements for heat dissipation and stability, and can significantly improve heat dissipation performance.

[0049] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0050] 1. Zinc oxide and other thermal conductive powders are used to improve the thixotropic properties of the product and reduce the problem of adhesive overflow at the interface during curing; at the same time, the compounding of various thermal conductive powders with different particle sizes improves the thermal conductivity of the product.

[0051] 2. Aluminate coupling agents and other surface modifiers are used to improve the interfacial compatibility between thermal conductive powder and silicone oil, enabling the thermal conductive powder to be dispersed evenly, reducing the viscosity of the system, and solving the structural problems during storage.

[0052] 3. Adding ketones such as chalcone as anti-aging additives can, under high temperature conditions, bind with the remaining silane groups in the system to prevent further cross-linking with vinyl groups in the system, resulting in a continuous increase in product hardness and improved high-temperature aging stability. At the same time, anti-aging additives containing phenyl groups can improve the heat resistance of the product. Detailed Implementation

[0053] To facilitate understanding of the present invention, preferred embodiments are provided below. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the present invention. The examples given are for illustrative purposes only and are not intended to limit the scope of the invention.

[0054] The main raw materials used in the various embodiments and comparative examples of this invention are sourced as follows. Unless otherwise specified, other raw materials and reagents were obtained through commercially available channels:

[0055] Vinyl silicone oils: QL-2311VDV50 (50cP), QL-2311VDV100 (100cP), QL-200DM200 (250cP), QL-200DM500 (500cP), Huangshan Qiangli Chemical Co., Ltd.

[0056] Polyether-modified silicone oil: SYLGARD TM OFX-0309(20cP), DOWSIL TM 5562 (50cP), XIAMETER TM OFX-5098 (250cP), DOWSIL TM 5604 (300 cP), Dow Chemical Company;

[0057] Spherical zinc oxide: Z-65 (0.5μm), Z-80 (1μm), Changzhou Boyang New Material Technology Co., Ltd.; ZnO908 (5μm), Jiangsu Haichuang Zinc Industry Technology Co., Ltd.;

[0058] Spherical alumina: NAS005 (0.5μm), NA1010W (1μm), NA1050 (5μm), Jiangsu Lianrui New Materials Co., Ltd.; BAK-10 (10μm), BAK-40 (40μm), Ya'an Baitu High-tech Materials Co., Ltd.

[0059] Other thermal conductive powders: YTA-5 (5μm aluminum hydroxide), YTM-1 (1μm magnesium hydroxide), YTM-8 (10μm magnesium hydroxide), Jinan Jinyingtai Chemical Co., Ltd.

[0060] Surface modifiers: HY-985 (aluminate coupling agent), HY-105 (phthalate coupling agent), Hangzhou Jessica Chemical Co., Ltd.;

[0061] Chalcones: H832838 (2-hydroxychalcone), F859937 (4'-fluorochalcone), Tianjin Xidian Chemical Technology Co., Ltd.;

[0062] Platinum catalysts: CSAT-F1 (divinyltetramethyldisiloxane platinum complex), CSAT-F6 (tetravinylcyclotetrasiloxane platinum complex), Suzhou Betterley Polymer Materials Co., Ltd.;

[0063] Hydrogen-containing silicone oils: CX-350 (10cP end hydrogen-containing silicone oil), CX-350LV (50cP end hydrogen-containing silicone oil), CX-351 (10cP side hydrogen-containing silicone oil), CX-351D (200cP side hydrogen-containing silicone oil), CX-351H (500cP side hydrogen-containing silicone oil), Guangzhou Chenxi New Material Technology Co., Ltd.

[0064] Inhibitors: YZJ-1 (ethynylcyclohexanol), YZJ-3 (tetramethyltetravinylcyclotetrasiloxane), Guangzhou Silicon Friends New Materials Technology Co., Ltd.

[0065] Example 1

[0066] Add 505g of 50cp vinyl silicone oil, 51g of 300cp polyether modified silicone oil, 3034g of 0.5μm spherical zinc oxide, 3033g of 5μm spherical alumina, and 3033g of 40μm spherical alumina to a double planetary mixer. Stir at 20rpm / min and disperse at 600rpm / min. Then add 51g of aluminate coupling agent, heat to 120℃, maintain the temperature, and stir under vacuum for 2h. After cooling to below 40℃, add 22g of 2-hydroxychalcone and 271g of divinyltetramethyldisiloxane platinum complex. Stir at 20rpm / min and disperse at 600rpm / min, stir under vacuum for 15min, and filter through a 100-mesh filter to obtain component A.

[0067] Add 205g of 50cp vinyl silicone oil, 3034g of 0.5μm spherical zinc oxide, 3033g of 5μm spherical alumina, and 3033g of 40μm spherical alumina to a double planetary mixer. Stir at 20rpm / min and disperse at 600rpm / min. Then add 173g of aluminate coupling agent, heat to 120℃, maintain the temperature, and stir under vacuum for 2h. After cooling to below 40℃, add 476g of 10cP end-hydrogen-containing silicone oil, 26g of 10cP side-hydrogen-containing silicone oil, and 20g of ethynylcyclohexanol. Stir at 20rpm / min and disperse at 600rpm / min under vacuum for 15min. Filter through a 100-mesh filter to obtain component B.

[0068] Sample 1 of Example is obtained by separately filling components A and B into tubing and sealing them for storage. When using, components A and B are combined and used in the required mass ratio.

[0069] Example 2

[0070] Add 460g of 100cp vinyl silicone oil, 198g of 250cp polyether modified silicone oil, 828g of 1μm spherical zinc oxide, 1378g of 1μm spherical alumina, and 6894g of 10μm spherical alumina to a double planetary mixer. Stir at 20 rpm / min and disperse at 600 rpm / min. Then add 94g of phthalate coupling agent, heat to 120℃, maintain the temperature, and stir under vacuum for 2 hours. After cooling to below 40℃, add 95g of 4'-fluorochalcone and 53g of tetravinylcyclotetrasiloxane platinum complex. Stir at 20 rpm / min and disperse at 600 rpm / min, stir under vacuum for 15 minutes, and filter through a 100-mesh filter to obtain component A.

[0071] Add 236g of 100cp vinyl silicone oil, 828g of 1μm spherical zinc oxide, 1378g of 1μm spherical alumina, and 6894g of 10μm spherical alumina to a double planetary mixer. Stir at 20 rpm / min and disperse at 600 rpm / min. Then add 54g of phthalate coupling agent, heat to 120℃, maintain the temperature, and stir under vacuum for 2 hours. After cooling to below 40℃, add 468g of 10cP end-hydrogen-containing silicone oil, 48g of 200cP side-hydrogen-containing silicone oil, and 94g of tetramethyltetravinylcyclotetrasiloxane. Stir at 20 rpm / min and disperse at 600 rpm / min under vacuum for 15 minutes. Filter through a 100-mesh filter to obtain component B.

[0072] Components A and B are separately bottled into tubing and sealed for storage to obtain Sample 2 of Example.

[0073] Example 3

[0074] Add 207g of 250cp vinyl silicone oil, 57g of 50cp polyether modified silicone oil, 4720g of 1μm spherical alumina, and 4720g of 10μm spherical alumina to a double planetary mixer. Stir at 20rpm / min and disperse at 600rpm / min. Then add 194g of aluminate coupling agent, heat to 120℃, maintain the temperature, and stir under vacuum for 2h. After cooling to below 40℃, add 34g of 2-hydroxychalcone and 68g of divinyltetramethyldisiloxane platinum complex. Stir at 20rpm / min and disperse at 600rpm / min, stir under vacuum for 15min, and filter through a 100-mesh filter to obtain component A.

[0075] Add 984g of 250cp vinyl silicone oil, 4020g of 1μm spherical alumina, and 4020g of 10μm spherical alumina to a double planetary mixer. Stir at 20 rpm / min and disperse at 600 rpm / min. Then add 52g of aluminate coupling agent, heat to 120℃, maintain the temperature, and stir under vacuum for 2 hours. After cooling to below 40℃, add 818g of 50cP end-hydrogen-containing silicone oil, 64g of 200cP side-hydrogen-containing silicone oil, and 42g of ethynylcyclohexanol. Stir at 20 rpm / min and disperse at 600 rpm / min under vacuum for 15 minutes. Filter through a 100-mesh filter to obtain component B.

[0076] Components A and B are separately bottled into tubing and sealed for storage to obtain Sample 3 of Example.

[0077] Example 4

[0078] Add 992g of 500cp vinyl silicone oil, 186g of 20cp polyether modified silicone oil, and 8270g of 5μm spherical alumina to a double planetary mixer. Stir at 20rpm / min and disperse at 600rpm / min. Then add 181g of phthalate coupling agent, heat to 120℃, maintain the temperature, and stir under vacuum for 2h. After cooling to below 40℃, add 82g of 4'-fluorochalcone and 289g of tetravinylcyclotetrasiloxane platinum complex. Stir at 20rpm / min and disperse at 600rpm / min, stir under vacuum for 15min, and filter through a 100-mesh filter to obtain component A.

[0079] Add 524g of 500cp vinyl silicone oil and 8360g of 5μm spherical alumina to a double planetary mixer. Stir at 20rpm / min and disperse at 600rpm / min. Then add 58g of phthalate coupling agent, heat to 120℃, maintain the temperature, and stir under vacuum for 2h. After cooling to below 40℃, add 887g of 50cP end-hydrogen-containing silicone oil, 96g of 500cP side-hydrogen-containing silicone oil, and 75g of tetramethyltetravinylcyclotetrasiloxane. Stir at 20rpm / min and disperse at 600rpm / min under vacuum for 15min. Filter through a 100-mesh filter to obtain component B.

[0080] Components A and B are separately bottled into tubing and sealed for storage to obtain Sample 4 of Example.

[0081] Comparative Example 1

[0082] The preparation method of Example 1 was followed, except that the spherical alumina with a particle size of 5 μm in both component A and component B was replaced with an equal mass of aluminum hydroxide with a particle size of 5 μm. Other operations and conditions remained unchanged, and component A and component B were obtained.

[0083] The components A and B were separately bottled into tubing and sealed for storage to obtain control sample 1.

[0084] Comparative Example 2

[0085] The preparation method of Example 2 is the same, except that in both component A and component B, the 1 μm spherical alumina particles are replaced with an equal mass of 1 μm magnesium hydroxide particles, and the 10 μm spherical alumina particles are replaced with an equal mass of 10 μm magnesium hydroxide particles. Other operations and conditions remain unchanged to obtain component A and component B.

[0086] Components A and B are separately bottled into tubing and sealed for storage to obtain control sample 2.

[0087] Comparative Example 3

[0088] The preparation method of Example 1 was followed, except that in both components A and B, the 0.5 μm spherical zinc oxide particles were replaced with an equal mass of 5 μm spherical zinc oxide particles, and the 5 μm spherical aluminum oxide particles were replaced with an equal mass of 5 μm aluminum hydroxide particles. All other operations and conditions remained unchanged, and components A and B were obtained.

[0089] Components A and B were separately bottled into tubing and sealed for storage to obtain control sample 2.

[0090] Comparative Example 4

[0091] The preparation method of Example 3 is the same, except that in both component A and component B, the 1 μm spherical alumina particles are replaced with an equal mass of 1 μm magnesium hydroxide particles, and the 10 μm spherical alumina particles are replaced with an equal mass of 10 μm magnesium hydroxide particles. Other operations and conditions remain unchanged to obtain component A and component B.

[0092] Components A and B were separately bottled into tubing and sealed for storage to obtain control sample 2.

[0093] Comparative Example 5

[0094] The preparation method of Example 1 is the same, except that no surface modifier is added after the thermally conductive powder is added to components A and B, and other operations and conditions remain unchanged, thus obtaining components A and B.

[0095] Components A and B were separately bottled into tubing and sealed for storage to obtain control sample 2.

[0096] Comparative Example 6

[0097] The preparation method of Example 1 was followed, except that no anti-aging additives were added to component A, while other operations and conditions remained unchanged, to obtain components A and B.

[0098] Components A and B were separately bottled into tubing and sealed for storage to obtain control sample 2.

[0099] Comparative Example 7

[0100] The preparation method of Example 1 was followed, except that the particle size of the thermally conductive powder (spherical zinc oxide and spherical aluminum oxide) in both component A and component B was replaced with 45 μm, while other operations and conditions remained unchanged, thus obtaining component A and component B.

[0101] The components A and B were separately bottled into tubing and sealed for storage to obtain control sample 1.

[0102] The thermally conductive gels prepared in Examples 1-4 and Comparative Examples 1-7 were subjected to performance tests:

[0103] The thermally conductive gels prepared in the above examples and comparative examples were heated in an oven at 60°C for 30 minutes to obtain fully cured sample blocks. The thermal conductivity of each sample block was tested under the same temperature and humidity conditions (temperature 25±2°C, humidity 50±5%RH). Simultaneously, the initial viscosity of components A and B mixed at a mass ratio of 1:1 in the thermally conductive gels prepared in each example and comparative example was tested at different rotation speeds, and the thixotropic value was calculated. The relevant comparative results are shown in Tables 1 and 2 below.

[0104] Thermal conductivity and hardness testing methods: After mixing and stirring components A and B of the thermally conductive gel evenly, vacuum degassing is performed, and the product is heated in a 60℃ oven to obtain the cured product. The sample is cut into the specified size according to GB / T531—1999 and the Shore 00 hardness is tested. The sample is cut into the specified size according to ASTM D5470 and the thermal conductivity is tested.

[0105] Viscosity and thixotropic testing methods: According to GB / T2794—1995, the viscosity values ​​of components A and B in the thermal conductive gel at 0.1 rpm and 1 rpm, and the viscosity values ​​of components A and B in the thermal conductive gel prepared in each example and comparative example at 25°C after being mixed evenly at a mass ratio of 1:1, were tested respectively. The thixotropic value was defined as the ratio of the viscosity at 0.1 rpm to the viscosity at 1 rpm.

[0106] Structured testing method: Pour a 3cm thick layer of thermally conductive gel consisting of components A and B into a cylindrical sample container with a diameter of 5cm. Test the cone penetration after 30 days according to GB / T269-91. When the cone penetration is less than 20mm, it is judged as structured.

[0107] High-temperature aging test method: Cut the test sample to the specified size according to GB / T531—1999, put the sample into ESPEC GPH-20 oven, heat at 150℃ for 1000h and test Shore 00 hardness.

[0108] Table 1. Comparison of viscosity and thermal conductivity of the thermally conductive gels prepared in the examples and comparative examples.

[0109]

[0110] Table 2 Comparison of the structured and high-temperature aging of the thermally conductive gels prepared in the examples and comparative examples.

[0111]

[0112] Comparing the performance data of the above examples and comparative examples of thermally conductive gels, under the same conditions, it can be found that the preferred solution of zinc oxide and alumina has lower viscosity and higher thixotropy when comparing Examples 1, 2, 3, and 4. Comparing Examples 1, 2, and 3 with Comparative Examples 1, 2, and 4, the thermal conductivity of the alumina and zinc oxide compound solution is significantly higher than that of other thermally conductive powder compound solutions. Comparing Example 1 with Comparative Example 3, when the minimum powder particle size is ≤1μm, the thixotropy of the product can be effectively improved, preventing glue loss before curing. Comparing Example 1 with Comparative Example 7, when the maximum particle size of the spherical alumina is >40μm, the particle size distribution changes, leading to increased viscosity, decreased thixotropy and thermal conductivity, and overall performance inferior to the preferred solution.

[0113] Example 1, with its surface modification using an aluminate coupling agent, showed a lower viscosity compared to Comparative Example 5 (which did not contain any surface modifier), and no structural problems were observed during subsequent storage. The addition of the aluminate coupling agent effectively reduced viscosity and prevented storage structuralization. In Example 1, the addition of chalcone as an anti-aging agent, compared to Comparative Example 6 (which did not contain any anti-aging agent), resulted in almost no change in hardness during high-temperature aging at 150°C for 1000 hours. The addition of chalcone effectively improved the stability of the thermally conductive gel during high-temperature aging after curing.

[0114] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A thermally conductive gel with high thermal conductivity and resistance to high-temperature aging, characterized in that, It includes component A and component B, wherein the mass ratio of component A to component B is 1:0.5~2; Based on the total weight of component A, it contains the following components by weight percentage: Based on the total weight of component B, it contains the following components by weight percentage: The thermally conductive powder is one or more of alumina, silicon micro powder, magnesium oxide, zinc oxide, aluminum nitride, silicon nitride, and carbon nanotubes; the particle size of the thermally conductive powder is ≤40μm. The anti-aging additive is chalcone.

2. The thermally conductive gel according to claim 1, characterized in that, The viscosity of the vinyl silicone oil is 50~500 cP.

3. The thermally conductive gel according to claim 1, characterized in that, The viscosity of the polyether-modified silicone oil is 20~300 cP.

4. The thermally conductive gel according to claim 1, characterized in that, The thermally conductive powder can be spherical, near-spherical, sheet-like, needle-like, or angular in shape.

5. The thermally conductive gel according to claim 4, characterized in that, The thermally conductive powder is in the form of spherical particles.

6. The thermally conductive gel according to claim 1, characterized in that, The thermally conductive powder is a combination of zinc oxide and aluminum oxide powder.

7. The thermally conductive gel according to claim 6, characterized in that, The combined mass ratio of zinc oxide to aluminum oxide is 1:(2~10).

8. The thermally conductive gel according to claim 6, characterized in that, The zinc oxide has a particle size ≤1μm.

9. The thermally conductive gel according to claim 6, characterized in that, The thermally conductive powder is a compound of at least one of alumina with a particle size of 1-5 μm and at least one of alumina with a particle size of 10-40 μm, and the mass ratio of the two is 1:(1-5).

10. The thermally conductive gel according to claim 1, characterized in that, The surface modifier is one or more of the following: aluminate coupling agent, silane coupling agent, titanate coupling agent, aluminum-titanium coupling agent, and organoboroate coupling agent.

11. The thermally conductive gel according to claim 10, characterized in that, The surface modifier is one or more of aluminate coupling agents.

12. The thermally conductive gel according to claim 1, characterized in that, The catalyst is selected from one or more of platinum compounds and their complexes, palladium compounds and their complexes, nickel compounds and their complexes, and rhodium compounds and their complexes.

13. The thermally conductive gel according to claim 12, characterized in that, The catalyst is selected from platinum compounds and their complexes.

14. The thermally conductive gel according to claim 1, characterized in that, The viscosity of the hydrogen-containing silicone oil is 10~500 cP.

15. The thermally conductive gel according to claim 14, characterized in that, The hydrogen-containing silicone oil is one or more of the following: end-containing hydrogen-containing silicone oil with a viscosity of 10-50 cP and side-containing hydrogen-containing silicone oil with a viscosity of 10-500 cP.

16. The thermally conductive gel according to claim 1, characterized in that, The inhibitor is one or more of tetramethyltetravinylcyclotetrasiloxane, methylbutynol, ethynylcyclohexanol, tetramethyldivinyldisiloxane, and phenylacetylene.

17. A method for preparing a high thermal conductivity, high-temperature aging resistant thermally conductive gel according to any one of claims 1-16, characterized in that, Includes the following steps: (1) Add vinyl silicone oil, polyether modified silicone oil and thermal conductive powder to a mixing tank and stir. Then add surface modifier and heat to 100~120℃, keep warm and vacuum stir. Then cool down to below 40℃, add anti-aging additive and catalyst, vacuum stir, and filter to obtain component A. (2) Add vinyl silicone oil and thermal conductive powder to a mixing tank and stir. Then add surface modifier and heat to 100~120℃, keep warm and stir under vacuum. Then cool down to below 40℃, add hydrogen-containing silicone oil and inhibitor, stir under vacuum, and filter to obtain component B.

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