Transformer-oil-resistant single-component high-thermal-conductivity gel as well as preparation method and application thereof

Abstract

The invention discloses transformer oil-resistant single-component high-thermal-conductivity gel, which is prepared from the following raw materials in percentage by weight: 2 to 10 percent of silicone oil, 80 to 96 percent of thermal conductive powder and 1.32 to 18.3 percent of auxiliaries, and the sum of the weight percentages of the preparation raw materials is 100 percent. The auxiliary agent at least comprises 1-10% of a reinforcing agent and 0.1-5% of a tackifier. By adopting the combination of the spherical aluminum oxide and spherical aluminum nitride heat-conducting powder, the heat-conducting property of the heat-conducting gel can be improved, and particularly in an ultrathin interface, the spherical heat-conducting powder has certain flowability, so that the heat-conducting effect can be improved. And the modified montmorillonite is introduced as a reinforcing agent, so that the scouring resistance and the heat-conducting property of the heat-conducting gel can be improved, and the heat-conducting powder is effectively prevented from entering the transformer oil along with the dissolution of the silicone oil. According to the invention, the erosion loss caused by dipping in the transformer oil can be effectively improved, so that smaller loss and higher heat-conducting property are kept.

Description

Technical Field

[0001] The invention relates to the field of organic polymer compound processing, and in particular to a transformer oil-resistant single-component high-thermal conductivity gel and a preparation method and application thereof. Background Art

[0002] With the rapid development of computer information technology, the increase in computing power has caused the heat generation of chips to become more and more serious, and the requirements for the thermal conductivity of materials have become higher and higher. At present, most of the thermal conductive materials on the market are thermal conductive silicone grease, which has good heat dissipation effect and low thermal resistance. At present, some chips will achieve high computing power by increasing the area, resulting in a large gap between the chip and the radiator. In order to improve the heat dissipation efficiency, the heating components will be immersed in transformer oil, and some heat will be taken away by the transformer oil. However, the flow contact between the transformer oil and the thermal conductive silicone grease will cause erosion loss of the thermal conductive silicone grease, resulting in the loss of the thermal conductive material and reducing the thermal conductivity. Therefore, it is very important to develop a thermal conductive material with high thermal conductivity efficiency and resistance to transformer oil erosion.

[0003] Chinese invention patent application CN113817178A discloses a low-oil permeability high-thermal-conductivity thermal-conductive gel and its preparation method, which uses vinyl silicone oil that has undergone secondary de-molecularization and is matched with low-density high-thermal-conductivity filler boron nitride to make the product have a low oil yield, while ensuring a thermal conductivity of 1.5-3.5W and a density of 2.0g / cm 3 China invention patent CN115403933B discloses a high extrusion and low oil permeability single-component thermal conductive gel and its preparation method, which uses boron trifluoride ether complex to treat the surface of boron nitride to increase the porosity of boron nitride, thereby increasing the adsorption capacity of boron nitride to silicone oil molecules, so that the thermal conductive gel has a good extrusion rate and a low oil permeability, but it is also not resistant to transformer oil erosion. Summary of the invention

[0004] In order to develop a thermally conductive material with high thermal conductivity and resistance to transformer oil erosion, the first aspect of the present invention provides a single-component high thermal conductivity gel resistant to transformer oil. The raw materials for preparation include 2-10% silicone oil, 80-96% thermally conductive powder and 1.32-18.3% auxiliary agent by weight percentage, and the sum of the weight percentages of the raw materials for preparation is 100%; the auxiliary agent includes at least 1-10% reinforcing agent and 0.1-5% tackifier by the total percentage of the thermally conductive gel; the reinforcing agent includes modified montmorillonite.

[0005] As an embodiment, the reinforcing agent includes at least one of carbon black, white carbon black, calcium carbonate, modified montmorillonite or kaolin.

[0006] As an implementation manner, the thermally conductive powder is spherical, and the particle size of the thermally conductive powder is 1-120 μm.

[0007] As an embodiment, the particle size of the thermally conductive powder is 1-90 μm.

[0008] As an embodiment, the particle size of the thermally conductive powder is a combination of 1-10 μm, 40-70 μm, and 50-90 μm.

[0009] As an embodiment, the thermally conductive powder includes at least one of aluminum oxide, aluminum hydroxide, zinc oxide, magnesium oxide, aluminum nitride, graphene, carbon fiber, carbon nanotube or diamond.

[0010] As an embodiment, the thermally conductive powder includes at least one of aluminum oxide and aluminum nitride.

[0011] During the experiment, the inventors found that modifying silicone oil with modified montmorillonite can improve the erosion resistance and thermal conductivity of the thermal conductive gel. The possible reasons are speculated to be: modified montmorillonite powder is hydrophilic and adsorbent. By introducing modified montmorillonite, a layer of hydrophilic structure can be added to the thermal conductive powder, which effectively prevents the thermal conductive powder from entering the transformer oil as the silicone oil dissolves. In addition, modified montmorillonite has a layered structure, which can better form a thermal conductive path in a thinner interface.

[0012] As an embodiment, the tackifier includes at least one of a borate tackifier, a hydrocarbon borate tackifier, an ester-containing siloxane tackifier, an epoxy-containing tackifier, a vinyl siloxane tackifier, a silicon hydrogen-containing oligomer, a β-diketosiloxane or an alkoxysilane tackifier.

[0013] As an embodiment, the adhesion promoter includes at least one of vinyl trimethoxy silane or 2,2'-diallyl bisphenol A.

[0014] The inventors further discovered during the experiment that the introduction of vinyl-containing tackifiers or epoxy-containing tackifiers into the thermally conductive gel can further improve the anti-erosion performance of the thermally conductive gel. The possible reason is that the use of vinyl-containing or epoxy-containing tackifiers increases the sites of cross-linking reactions, converting the linear vinyl silicone oil into a three-dimensional network structure with branches connected to each other, which can be wrapped around the thermally conductive powder, increasing the steric hindrance between molecules and reducing the loss of the thermally conductive powder. In addition, the thermally conductive gel with a three-dimensional network structure increases the bonding effect on the substrate, further improving the anti-erosion performance of the thermally conductive gel against transformer oil, thereby ensuring smaller losses and higher thermal conductivity.

[0015] As an embodiment, the auxiliary agent also includes a crosslinking agent, a coupling agent, an inhibitor and a catalyst, and the crosslinking agent includes at least one of terminal hydrogen-containing silicone oil and side hydrogen-containing silicone oil; the hydrogen content of the terminal hydrogen-containing silicone oil and the side hydrogen-containing silicone oil is 0.05-1.5wt%.

[0016] As an embodiment, based on the weight percentage of the single-component high thermal conductivity gel, the auxiliary agent also includes 0.01-1% of a cross-linking agent, 0.1-1.5% of a coupling agent, 0.01-0.3% of an inhibitor, and 0.1-0.5% of a catalyst.

[0017] As an embodiment, the crosslinking agent includes pendant hydrogen-containing silicone oil.

[0018] As an embodiment, the silicone oil includes at least one of vinyl-terminated silicone oil, side vinyl-terminated silicone oil, vinyl-terminated dimethyl silicone oil or hydroxy silicone oil.

[0019] As an embodiment, the viscosity of the cross-linking agent at 25°C is 20-200 mm² / s, and the viscosity of the silicone oil at 25°C is 100-5000 mm² / s.

[0020] As an embodiment, the coupling agent includes but is not limited to at least one of octyltrimethoxysilane, octyltriethoxysilane, decyltrimethoxysilane, decyltriethoxysilane, dodecyltrimethoxysilane, dodecyltriethoxysilane, glycidyl ether ethyltrimethoxysilane or hexadecyltrimethoxysilane.

[0021] As an embodiment, the coupling agent includes at least one of dodecyltrimethoxysilane or hexadecyltrimethoxysilane.

[0022] As an embodiment, the inhibitor includes but is not limited to at least one of ethynyl cyclohexanol, 3-methyl-1-pentyn-3-ol, 3-phenyl-1-butyn-3-ol butynol or 11-trimethyldodecyn-3-ol.

[0023] In one embodiment, the inhibitor includes ethynyl cyclohexanol.

[0024] As an embodiment, the catalyst is a Pt catalyst, and the Pt content is 1000-5000ppm. (Pt content refers to the Pt content in the catalyst of 1000-5000ppm) As an embodiment, the catalyst is a Custer catalyst. The second aspect of the present invention provides a method for preparing a transformer oil-resistant single-component high thermal conductivity gel, comprising the following steps: S1 Add silicone oil, thermal conductive powder, coupling agent and tackifier into a planetary mixer and stir for 1-2 hours at a stirring speed of 20-60r / min; Add reinforcing agent to S2, raise the temperature to 100-180℃, stir under vacuum for 1-3h, and rotate at 20-60r / min; S3 is cooled to 25°C, cross-linking agent and inhibitor are added, and vacuum stirring is performed for 0.5-2h at a speed of 20-60r / min; Add catalyst to S4, raise the temperature to 120-180℃, stir under vacuum for 1-2h, and rotate at 20-60r / min; S5 is cooled to 25°C to obtain a single-component high thermal conductive gel.

[0025] The third aspect of the present invention provides an application of a transformer oil-resistant single-component high thermal conductivity gel, which is applied to electronic thermal conductive components.

[0026] Compared with the prior art, the present invention has the following beneficial effects: (1) The transformer oil-resistant single-component high thermal conductivity gel of the present invention adopts a combination of spherical alumina and spherical aluminum nitride thermal conductive powders, which can improve the thermal conductivity of the thermal conductive gel. In particular, in ultra-thin interfaces, the spherical thermal conductive powders have a certain fluidity, which can improve the thermal conductivity effect.

[0027] (2) The transformer oil-resistant single-component high thermal conductivity gel of the present invention has a thermally conductive powder with a combination of three particle sizes of 1-10 μm, 40-70 μm, and 50-90 μm, which can further increase the connection between the thermally conductive powders, reduce the gaps between the thermally conductive powders, and further improve the thermal conductivity.

[0028] (3) The transformer oil-resistant single-component high thermal conductivity gel of the present invention introduces modified montmorillonite as a reinforcing agent to improve the erosion resistance and thermal conductivity of the thermal conductive gel, and effectively prevent the thermal conductive powder from entering the transformer oil as the silicone oil dissolves.

[0029] (4) The transformer oil-resistant single-component high thermal conductivity gel of the present invention can further improve the anti-erosion performance of the thermal conductive gel by introducing a vinyl-containing tackifier or an epoxy-containing tackifier, reduce the loss of thermal conductive powder, and increase the bonding effect to the substrate.

[0030] (5) The transformer oil-resistant single-component high thermal conductivity gel of the present invention can effectively improve the erosion loss caused by immersion in transformer oil, thereby maintaining a small loss and a high thermal conductivity. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is an exemplary diagram of the transformer oil-resistant single-component high thermal conductivity gel prepared in the embodiment in a transformer oil circulation working environment.

[0032] In the figure: 1. Thermally conductive gel. DETAILED DESCRIPTION

[0033] The raw materials of the embodiments and comparative examples were purchased from the following manufacturers: 2 μm spherical alumina was purchased from Bengbu Zhongheng New Materials Technology Co., Ltd., model CTE02; 40 μm spherical alumina was purchased from Bengbu Zhongheng New Materials Technology Co., Ltd., model CTE40; 5 μm spherical alumina was purchased from Bengbu Zhongheng New Materials Technology Co., Ltd., model CTE05; 50 μm spherical alumina was purchased from Bengbu Zhongheng New Materials Technology Co., Ltd., model CTE50; 70 μm spherical alumina was purchased from Bengbu Zhongheng New Materials Technology Co., Ltd., model CTE70; 90 μm spherical alumina was purchased from Bengbu Zhongheng New Materials Technology Co., Ltd., model CTE90; Spherical aluminum nitride with a diameter of 80 μm was purchased from Ya'an Baitu High-tech Materials Co., Ltd., model TA-S80.

[0034] The viscosity at 25°C is 1000 mm² / s. The vinyl-terminated silicone oil was purchased from Dongguan Xinkang Silicone Materials Co., Ltd., model number LK-3011; The viscosity at 25°C is 500 mm² / s. The vinyl-terminated silicone oil was purchased from Dongguan Xinkang Silicone Materials Co., Ltd., model number LK3030-500.

[0035] The Custer catalyst with a Pt content of 3000 ppm was purchased from Guangzhou Siyou New Materials Co., Ltd., model PT-3000SW; The Custer catalyst with a Pt content of 5000 ppm was purchased from Guangzhou Siyou New Materials Co., Ltd., model PT-5000SW.

[0036] The side-group hydrogen-containing silicone oil with a hydrogen content of 0.5 wt% was purchased from Ningbo Runhe High-tech Materials Technology Co., Ltd., model RH-H503; The side-group hydrogen-containing silicone oil with a hydrogen content of 0.36 wt% was purchased from Ningbo Runhe High-tech Materials Technology Co., Ltd., model RH-H536; The side-group hydrogen-containing silicone oil with a hydrogen content of 0.18 wt% was purchased from Ningbo Runhe High-tech Materials Technology Co., Ltd., model RH-H33; The side-group hydrogen-containing silicone oil with a hydrogen content of 0.1 wt% was purchased from Ningbo Runhe High-tech Materials Technology Co., Ltd., model RH-H86; The side-group hydrogen-containing silicone oil with a hydrogen content of 0.15 wt% was purchased from Ningbo Runhe High-tech Materials Technology Co., Ltd., model RH-H57.

[0037] Example 1 A transformer oil-resistant single-component high thermal conductivity gel 1 is prepared from raw materials including 500 g of silicone oil, 5000 g of thermal conductive powder and 277.4 g of an auxiliary agent.

[0038] The thermally conductive powder includes 2500 g of spherical alumina with a particle size of 2 μm and 2500 g of spherical alumina with a particle size of 40 μm.

[0039] The silicone oil is vinyl-terminated silicone oil, and the viscosity at 25° C. is 1000 mm² / s.

[0040] The auxiliary agent includes 15g of coupling agent which is dodecyltrimethoxysilane, 15g of tackifier which is vinyltrimethoxysilane, 240g of reinforcing agent which is modified montmorillonite, 0.8g of cross-linking agent which is side-group hydrogenated silicone oil, 0.6g of inhibitor which is ethynylcyclohexanol, 6g of catalyst which is Custer catalyst, and the Pt content is 3000ppm.

[0041] The hydrogen content of the side-group hydrogen-containing silicone oil is 0.5 wt %.

[0042] The modified montmorillonite was purchased from Lingshou County China Resources Mineral Powder Processing Plant, model number dr-103.

[0043] A method for preparing a transformer oil-resistant single-component high thermal conductivity gel comprises the following steps: S1 Add silicone oil, thermal conductive powder, coupling agent and tackifier into a planetary mixer and stir for 1 hour at a stirring speed of 40 r / min; Add reinforcing agent to S2, raise the temperature to 120℃, stir under vacuum for 2h, and rotate at 50r / min; S3 is cooled to 25℃, cross-linking agent and inhibitor are added, and vacuum stirring is performed for 1h at a speed of 50r / min; Add catalyst to S4, raise the temperature to 150°C, and stir under vacuum for 1.5h at a speed of 50r / min; S5 is cooled to 25°C to obtain a single-component high thermal conductive gel.

[0044] Example 2 A transformer oil-resistant single-component high thermal conductivity gel 1 is prepared from raw materials including 500 g of silicone oil, 5800 g of thermal conductive powder and 349.2 g of an auxiliary agent.

[0045] The thermally conductive powder includes 2400 g of spherical alumina with a particle size of 5 μm and 3400 g of spherical alumina with a particle size of 50 μm.

[0046] The silicone oil is vinyl-terminated silicone oil, and the viscosity at 25° C. is 1000 mm² / s.

[0047] The auxiliary agent includes 20g of hexadecyltrimethoxysilane as a coupling agent, 20g of vinyltrimethoxysilane as a tackifier, 300g of modified montmorillonite as a reinforcing agent, 1.2g of side-group hydrogenated silicone oil as a cross-linking agent, 1g of ethynylcyclohexanol as an inhibitor, 7g of a Custer catalyst, and a Pt content of 3000ppm.

[0048] The hydrogen content of the side-group hydrogen-containing silicone oil is 0.36 wt %.

[0049] The modified montmorillonite was purchased from Lingshou County China Resources Mineral Powder Processing Plant, model number dr-103.

[0050] A method for preparing a transformer oil-resistant single-component high thermal conductivity gel comprises the following steps: S1 Add silicone oil, thermal conductive powder, coupling agent and tackifier into a planetary mixer and stir for 1 hour at a stirring speed of 50 r / min; Add reinforcing agent to S2, raise the temperature to 120℃, stir under vacuum for 2h, and rotate at 50r / min; S3 is cooled to 25℃, cross-linking agent and inhibitor are added, and vacuum stirring is performed for 1h at a speed of 50r / min; Add catalyst to S4, raise the temperature to 150°C, and stir under vacuum for 1.5h at a speed of 50r / min; S5 is cooled to 25°C to obtain a single-component high thermal conductive gel.

[0051] Example 3 A transformer oil-resistant single-component high thermal conductivity gel 1 is prepared from raw materials including 500 g of silicone oil, 7200 g of thermal conductive powder and 442.5 g of an auxiliary agent.

[0052] The thermally conductive powder includes 3000 g of spherical alumina with a particle size of 5 μm and 4200 g of spherical alumina with a particle size of 70 μm.

[0053] The silicone oil is vinyl-terminated silicone oil, and the viscosity at 25° C. is 500 mm² / s.

[0054] The auxiliary agent includes 30g of coupling agent which is hexadecyltrimethoxysilane, 40g of tackifier which is 2,2'-diallylbisphenol A, 360g of reinforcing agent which is modified montmorillonite, 3g of cross-linking agent which is side-group hydrogenated silicone oil, 1.5g of inhibitor which is ethynylcyclohexanol, 9g of catalyst which is Custer catalyst, and Pt content is 5000ppm.

[0055] The hydrogen content of the side-group hydrogen-containing silicone oil is 0.18 wt %.

[0056] The modified montmorillonite was purchased from Lingshou County China Resources Mineral Powder Processing Plant, model number dr-103.

[0057] A method for preparing a transformer oil-resistant single-component high thermal conductivity gel comprises the following steps: S1 Add silicone oil, thermal conductive powder, coupling agent and tackifier into a planetary mixer and stir for 1 hour at a stirring speed of 50 r / min; Add reinforcing agent to S2, raise the temperature to 120℃, stir under vacuum for 2h, and rotate at 50r / min; S3 is cooled to 25℃, cross-linking agent and inhibitor are added, and vacuum stirring is performed for 1h at a speed of 50r / min; Add catalyst to S4, raise the temperature to 150°C, and stir under vacuum for 1.5h at a speed of 50r / min; S5 is cooled to 25°C to obtain a single-component high thermal conductive gel.

[0058] Example 4 A transformer oil-resistant single-component high thermal conductivity gel 1 is prepared from raw materials including 500 g of silicone oil, 8500 g of thermal conductive powder and 741.1 g of an auxiliary agent.

[0059] The thermally conductive powder includes 1500 g of spherical alumina with a particle size of 5 μm, 4500 g of spherical alumina with a particle size of 40 μm, and 2500 g of spherical alumina with a particle size of 90 μm.

[0060] The silicone oil is vinyl-terminated dimethyl silicone oil, and the viscosity at 25° C. is 500 mm² / s.

[0061] The auxiliary agent includes 45g of coupling agent which is dodecyltrimethoxysilane, 80g of tackifier which is 2,2'-diallylbisphenol A, 600g of reinforcing agent which is modified montmorillonite, 4.5g of cross-linking agent which is side-group hydrogenated silicone oil, 1.6g of inhibitor which is ethynylcyclohexanol, 10g of catalyst which is Custer catalyst, and Pt content is 5000ppm.

[0062] The hydrogen content of the side-group hydrogen-containing silicone oil is 0.1 wt %.

[0063] The modified montmorillonite was purchased from Lingshou County China Resources Mineral Powder Processing Plant, model number dr-103.

[0064] A method for preparing a transformer oil-resistant single-component high thermal conductivity gel comprises the following steps: S1 Add silicone oil, thermal conductive powder, coupling agent and tackifier into a planetary mixer and stir for 1.5 hours at a stirring speed of 50 r / min; Add reinforcing agent to S2, raise the temperature to 150℃, stir under vacuum for 2h, and rotate at 50r / min; S3 is cooled to 25℃, cross-linking agent and inhibitor are added, and vacuum stirring is performed for 1h at a speed of 50r / min; Add catalyst to S4, raise the temperature to 150℃, stir under vacuum for 2h, and rotate at 50r / min; S5 is cooled to 25°C to obtain a single-component high thermal conductive gel.

[0065] Example 5 A transformer oil-resistant single-component high thermal conductivity gel 1 is prepared from raw materials including 500 g of silicone oil, 8100 g of thermal conductive powder and 522.8 g of an auxiliary agent.

[0066] The thermally conductive powder includes 1200 g of spherical aluminum oxide with a particle size of 5 μm, 4500 g of spherical aluminum oxide with a particle size of 50 μm, and 2400 g of spherical aluminum nitride with a particle size of 80 μm.

[0067] The silicone oil is vinyl-terminated silicone oil, and the viscosity at 25° C. is 500 mm² / s.

[0068] The auxiliary agent includes 36g of coupling agent which is dodecyltrimethoxysilane, 70g of tackifier which is 2,2'-diallylbisphenol A, 400g of reinforcing agent which is modified montmorillonite, 3g of cross-linking agent which is side-group hydrogenated silicone oil, 1.8g of inhibitor which is ethynylcyclohexanol, 12g of catalyst which is Custer catalyst, and Pt content is 3000ppm.

[0069] The hydrogen content of the side-group hydrogen-containing silicone oil is 0.15 wt %.

[0070] The modified montmorillonite was purchased from Lingshou County China Resources Mineral Powder Processing Plant, model number dr-103.

[0071] A method for preparing a transformer oil-resistant single-component high thermal conductivity gel comprises the following steps: S1 Add silicone oil, thermal conductive powder, coupling agent and tackifier into a planetary mixer and stir for 1.5 hours at a stirring speed of 50 r / min; Add reinforcing agent to S2, raise the temperature to 150℃, and stir under vacuum for 2.5h at a speed of 50r / min; S3 is cooled to 25°C, cross-linking agent and inhibitor are added, and vacuum stirring is performed for 1.5 h at a speed of 50 r / min; Add catalyst to S4, raise the temperature to 150℃, stir under vacuum for 2h, and rotate at 50r / min; S5 is cooled to 25°C to obtain a single-component high thermal conductive gel.

[0072] The prepared transformer oil-resistant single-component high thermal conductivity gel is shown in the example diagram in the transformer oil circulation working environment. Figure 1 The prepared thermally conductive gel is the thermally conductive gel 1 in the figure.

[0073] Comparative Example 1 A transformer oil-resistant single-component high-thermal-conductivity gel is prepared from raw materials including 500 g of silicone oil, 5000 g of thermal-conductive powder and 22.4 g of an auxiliary agent.

[0074] The thermally conductive powder includes 2500 g of spherical alumina with a particle size of 2 μm and 2500 g of spherical alumina with a particle size of 40 μm.

[0075] The silicone oil is vinyl-terminated silicone oil, and the viscosity at 25° C. is 500 mm² / s.

[0076] The auxiliary agent includes 15g of coupling agent which is dodecyltrimethoxysilane, 0.8g of cross-linking agent which is side-group hydrogenated silicone oil, 0.6g of inhibitor which is ethynylcyclohexanol, 6g of catalyst which is Custer catalyst, and the Pt content is 3000ppm.

[0077] The hydrogen content of the side-group hydrogen-containing silicone oil is 0.5 wt %.

[0078] A method for preparing a transformer oil-resistant single-component high thermal conductivity gel comprises the following steps: S1 Add silicone oil, thermal conductive powder, coupling agent, crosslinking agent and inhibitor into a planetary mixer and stir for 1.5 hours at a stirring speed of 50 r / min; Add catalyst to S2, raise the temperature to 150°C, and stir under vacuum for 1.5h at a speed of 50r / min; S3 is cooled to 25°C to obtain a single-component high thermal conductive gel.

[0079] Comparative Example 2 A transformer oil-resistant single-component high-thermal-conductivity gel is prepared from raw materials including 500 g of silicone oil, 7200 g of thermal-conductive powder and 42.5 g of an auxiliary agent.

[0080] The thermally conductive powder includes 3000 g of spherical alumina with a particle size of 5 μm and 4200 g of spherical alumina with a particle size of 70 μm.

[0081] The silicone oil is vinyl-terminated silicone oil, and the viscosity at 25° C. is 500 mm² / s.

[0082] The auxiliary agent includes 30g of coupling agent which is hexadecyltrimethoxysilane, 3g of cross-linking agent which is side-group hydrogenated silicone oil, 1.5g of inhibitor which is ethynylcyclohexanol, 8g of catalyst which is Custer catalyst, and the Pt content is 3000ppm.

[0083] The hydrogen content of the side-group hydrogen-containing silicone oil is 0.18 wt %.

[0084] A method for preparing a transformer oil-resistant single-component high thermal conductivity gel comprises the following steps: S1 Add silicone oil, thermal conductive powder, coupling agent, crosslinking agent and inhibitor into a planetary mixer and stir for 2 hours at a stirring speed of 50 r / min; Add catalyst to S2, raise the temperature to 120℃, and stir under vacuum for 1.5h at a speed of 50r / min; S3 is cooled to 25°C to obtain a single-component high thermal conductive gel.

[0085] Comparative Example 3 A transformer oil-resistant single-component high-thermal-conductivity gel is prepared from raw materials including 500 g of silicone oil, 8200 g of thermal-conductive powder and 52.8 g of an auxiliary agent.

[0086] The thermally conductive powder includes 1200 g of spherical aluminum oxide with a particle size of 5 μm, 4500 g of spherical aluminum oxide with a particle size of 50 μm, and 2500 g of spherical aluminum nitride with a particle size of 80 μm.

[0087] The silicone oil is vinyl-terminated silicone oil, and the viscosity at 25° C. is 500 mm² / s.

[0088] The auxiliary agent includes 36g of coupling agent which is dodecyltrimethoxysilane, 3g of cross-linking agent which is side-group hydrogenated silicone oil, 1.8g of inhibitor which is ethynylcyclohexanol, 12g of catalyst which is Custer catalyst, and the Pt content is 3000ppm.

[0089] The hydrogen content of the side-group hydrogen-containing silicone oil is 0.15 wt %.

[0090] A method for preparing a transformer oil-resistant single-component high thermal conductivity gel comprises the following steps: S1 Add silicone oil, thermal conductive powder, coupling agent, crosslinking agent and inhibitor into a planetary mixer and stir for 2 hours at a stirring speed of 50 r / min; Add catalyst to S2, raise the temperature to 150°C, and stir under vacuum for 2h at a speed of 50r / min; S3 is cooled to 25°C to obtain a single-component high thermal conductive gel.

[0091] Performance Testing 1. Thermal conductivity: Refer to ASTM D5470 standard test thermal conductivity.

[0092] 2. Temperature rise test and weight loss ratio: The thermal conductive gel of the embodiment and the comparative example was coated on a copper plate of 150×150×2 mm, with the coating specification of Φ30×2 mm (diameter 30 mm thickness 2 mm), and fixed with a heating element assembly. After running for 24 hours, the surface temperature rise of the copper plate was tested with a temperature rise tester, and the weight of the thermal conductive gel was weighed as m0.

[0093] Soak the workpiece in a container filled with transformer oil for 1000 hours, take it out and air dry it naturally, run it for 24 hours, test the surface temperature rise of the copper plate with a temperature rise tester, weigh the weight of the thermal conductive gel after soaking and drying as m1, and calculate the weight loss ratio before and after soaking. Weight loss ratio = (m0-m1) / m0×100%.

[0094] The test results are shown in Table 1 below.

[0095] Table 1

[0096] The results show that the single-component high thermal conductivity gel of the present invention can effectively improve the erosion loss caused by immersion in transformer oil, thereby maintaining a smaller loss and a higher thermal conductivity.

Claims

1. A transformer oil-resistant single-component high thermal conductivity gel, characterized in that: In terms of weight percentage, the raw materials include 2-10% silicone oil, 80-96% thermal conductive powder and 1.32-18.3% auxiliary agent, and the sum of the weight percentages of the raw materials is 100%; in terms of the total percentage of the thermal conductive gel, the auxiliary agent includes at least 1-10% reinforcing agent and 0.1-5% viscosity enhancer; the reinforcing agent includes modified montmorillonite.

2. The transformer oil-resistant single-component high thermal conductivity gel according to claim 1, characterized in that: The thermally conductive powder is spherical, and the particle size of the thermally conductive powder is 1-120 μm.

3. The transformer oil-resistant single-component high thermal conductivity gel according to claim 2, characterized in that: The thermally conductive powder includes at least one of aluminum oxide, aluminum hydroxide, zinc oxide, magnesium oxide, aluminum nitride, graphene, carbon fiber powder, carbon nanotubes or diamond.

4. The transformer oil-resistant single-component high thermal conductivity gel according to claim 1, characterized in that: The tackifier includes at least one of a borate tackifier, a hydrocarbon borate tackifier, an ester-containing siloxane tackifier, an epoxy-containing tackifier, a vinyl siloxane tackifier, a silicon hydrogen-containing oligomer, a β-diketone siloxane or an alkoxysilane tackifier.

5. The transformer oil-resistant single-component high thermal conductivity gel according to claim 1, characterized in that: The auxiliary agent also includes a crosslinking agent, a coupling agent, an inhibitor and a catalyst. The crosslinking agent includes at least one of terminal hydrogen-containing silicone oil and side hydrogen-containing silicone oil.

6. The transformer oil-resistant single-component high thermal conductivity gel according to claim 5, characterized in that: The hydrogen content of the terminal hydrogen-containing silicone oil and the side hydrogen-containing silicone oil is 0.05-1.5wt%.

7. The transformer oil-resistant single-component high thermal conductivity gel according to claim 1, characterized in that: The silicone oil includes at least one of vinyl-terminated silicone oil, side vinyl-terminated silicone oil, dimethyl silicone oil or hydroxy silicone oil.

8. The transformer oil-resistant single-component high thermal conductivity gel according to claim 6, characterized in that: The viscosity of the cross-linking agent at 25° C. is 20-200 mm² / s, and the viscosity of the silicone oil at 25° C. is 100-5000 mm² / s.

9. A method for preparing the transformer oil-resistant single-component high thermal conductivity gel according to any one of claims 6 to 8, characterized in that: The following steps are involved: S1 Add silicone oil, thermal conductive powder, coupling agent and tackifier into a mixer and stir for 1-2 hours at a stirring speed of 20-60 r / min; Add reinforcing agent to S2, raise the temperature to 100-180℃, stir under vacuum for 1-3h, and rotate at 20-60r / min; S3 is cooled to 25°C, cross-linking agent and inhibitor are added, and vacuum stirring is performed for 0.5-2h at a speed of 20-60r / min; Add catalyst to S4, raise the temperature to 120-180℃, stir under vacuum for 1-2h, and rotate at 20-60r / min; S5 is cooled to 25°C to obtain a single-component high thermal conductive gel.

10. An application of the transformer oil-resistant single-component high thermal conductivity gel according to any one of claims 1 to 8, characterized in that: Used in electronic thermal conductive components.

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