High-temperature-resistant heat-conducting silicone grease and preparation method thereof

Abstract

The invention provides high-temperature-resistant heat-conducting silicone grease. The high-temperature-resistant heat-conducting silicone grease comprises the following components in parts by weight: 100 parts of methyl phenyl silicone oil, 300-1000 parts of modified heat-conducting powder and 0.5-3 parts of a heat-resistant additive, wherein the viscosity of the methyl phenyl silicone oil at 25 DEG C is 50-500 mPa.s, and the phenyl content of the methyl phenyl silicone oil is 25-50%. By adding the combination of the methyl phenyl silicone oil and the heat-resistant additive, molecular chain breakage of an organic silicon-based material in a high-temperature environment can be inhibited, so that the durability of the silicone grease is ensured, the service time in the high-temperature environment is longer, and the high-temperature resistance of conventional heat-conducting silicone grease is improved.

Description

Technical Field

[0001] The present application relates to the field of chemical technology, and in particular to a high-temperature resistant thermally conductive silicone grease and a preparation method thereof. Background Art

[0002] With technological advancements, the circuit designs of modern electronic instruments and equipment are becoming increasingly complex and integrated. To ensure the stable operation of these highly integrated devices, the heat generated by each electronic component must be effectively and promptly conducted away. Thermal interface materials can effectively fill the air gap between the heat-generating device and the heat sink, thereby creating an excellent heat transfer path and improving the device's heat dissipation efficiency. Thermal grease, due to its extremely low thermal resistance, low price, and excellent interface wettability, performs an irreplaceable role among other thermal interface materials and is widely used between various heat sinks and heat-generating power devices.

[0003] Although silicone materials have good temperature resistance, their molecular chains are prone to breaking and aging when exposed to high temperatures and the presence of air for a long time. This causes the thermally conductive silicone materials to dry out, crack, and powder over a long period of use, thereby reducing their thermal conductivity. Summary of the Invention

[0004] In view of the above problems, the present application is proposed to provide a high-temperature resistant thermally conductive silicone grease and a preparation method thereof that overcomes the above problems or at least partially solves the above problems, comprising:

[0005] A high-temperature resistant thermally conductive silicone grease, comprising, by weight, 100 parts of methylphenyl silicone oil, 300-1000 parts of modified thermally conductive powder, and 0.5-3 parts of a heat-resistant additive;

[0006] The viscosity of the methylphenyl silicone oil at 25° C. is 50-500 mPa·s, and the phenyl content of the methylphenyl silicone oil is 25-50%.

[0007] Furthermore, the heat-resistant additive is one or more of ferric oxide, cerium oxide, and carbon black.

[0008] Furthermore, the modified thermally conductive powder includes a coupling agent and thermally conductive powder.

[0009] Furthermore, the coupling agent includes one or more of 3-aminopropylethoxysiloxane, γ-glycidyloxypropyltrimethoxysilane, γ-(methacryloyloxy)propyltrimethoxysilane, dodecyltrimethoxysilane, vinyltriethoxysilane, titanate coupling agent, and aluminate coupling agent.

[0010] Furthermore, the thermally conductive powder includes one or more of aluminum oxide, magnesium oxide, zinc oxide, aluminum nitride, boron nitride, silicon nitride, and silicon carbide.

[0011] A method for preparing high-temperature resistant thermally conductive silicone grease comprises the following steps:

[0012] Mixing and stirring methylphenyl silicone oil, modified thermal conductive powder and heat-resistant additive to obtain a premixed high-temperature resistant thermal conductive silicone grease; wherein, based on parts by weight, the mixing ratio is: 100 parts of methylphenyl silicone oil, 300-1000 parts of modified thermal conductive powder, and 0.5-3 parts of heat-resistant additive;

[0013] The premixed high-temperature resistant thermally conductive silicone grease is subjected to vacuum degassing treatment to obtain the high-temperature resistant thermally conductive silicone grease.

[0014] Furthermore, the method further includes: preparing modified thermally conductive powder by using a coupling agent and thermally conductive powder.

[0015] Furthermore, the step of preparing the modified thermally conductive powder by using a coupling agent and thermally conductive powder comprises:

[0016] Mix the thermal conductive powder, coupling agent and solvent according to the preset ratio and stir for 10-20 minutes;

[0017] Heat to 80-100°C and stir for 30-60 minutes to obtain a modified thermal conductive powder mixture;

[0018] The modified thermally conductive powder mixture is subjected to a vacuum desolventizing treatment to obtain the modified thermally conductive powder.

[0019] Furthermore, the solvent is one of ethyl acetate or cyclohexanone.

[0020] Furthermore, based on mass, the mass ratio of the thermally conductive powder, the coupling agent and the solvent is 100:1:50.

[0021] This application has the following advantages:

[0022] In the embodiments of the present application, to address the shortcomings of existing thermal greases in the art, such as molecular chain breakage and aging during long-term use, which can cause the silicone material to dry out and crack, thereby reducing heat transfer performance, the present application provides a high-temperature resistant thermal grease comprising, by weight, 100 parts methylphenyl silicone oil, 300-1000 parts modified thermal conductive powder, and 0.5-3 parts heat-resistant additive. The methylphenyl silicone oil has a viscosity of 50-500 mPa·s at 25°C and a phenyl content of 25-50%. The combination of methylphenyl silicone oil and heat-resistant additives can inhibit molecular chain breakage in the silicone-based material in high-temperature environments, thereby ensuring the durability of the grease, extending its service life in high-temperature environments, and improving the high-temperature resistance of conventional thermal greases. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for use in the description of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0024] Figure 1 This is a flow chart of the steps of a method for preparing high-temperature resistant thermal conductive silicone grease provided in one embodiment of the present application. DETAILED DESCRIPTION

[0025] To make the objectives, features, and advantages of this application more readily apparent, the present application is further described below in conjunction with the accompanying drawings and specific embodiments. It is apparent that the embodiments described are only a portion of the embodiments of this application, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments in this application without inventive effort are also within the scope of protection of this application.

[0026] By analyzing the existing technology, the inventors found that although silicone materials have good temperature resistance in the existing technology, their molecular chains are prone to breaking and aging when exposed to high temperatures and the presence of air for a long time. As a result, the thermally conductive silicone materials are prone to drying, cracking, and powdering during long-term use, thereby reducing their thermal conductivity.

[0027] In the embodiments of the present application, to address the shortcomings of existing thermal greases in the art, such as molecular chain breakage and aging during long-term use, which can cause the silicone material to dry out and crack, thereby reducing heat transfer performance, the present application provides a high-temperature resistant thermal grease comprising, by weight, 100 parts methylphenyl silicone oil, 300-1000 parts modified thermal conductive powder, and 0.5-3 parts heat-resistant additive. The methylphenyl silicone oil has a viscosity of 50-500 mPa·s at 25°C and a phenyl content of 25-50%. The combination of methylphenyl silicone oil and heat-resistant additives can inhibit molecular chain breakage in the silicone-based material in high-temperature environments, thereby ensuring the durability of the grease, extending its service life in high-temperature environments, and improving the high-temperature resistance of conventional thermal greases.

[0028] It should be noted that the addition of heat-resistant additives and modified thermal conductive powder can improve the overall heat resistance of silicone grease, thereby improving the durability of silicone grease.

[0029] Next, a high-temperature resistant thermally conductive silicone grease in this exemplary embodiment will be further described.

[0030] In one embodiment of the present application, the heat-resistant additive is one or more of ferric oxide, cerium oxide, and carbon black.

[0031] In one embodiment of the present application, the modified thermally conductive powder includes a coupling agent and thermally conductive powder.

[0032] It should be noted that the thermally conductive powder is modified by mixing the coupling agent and the thermally conductive powder in a solvent, reacting the mixture, and then removing the solvent to obtain a modified thermally conductive powder with better thermal conductivity.

[0033] In one embodiment of the present application, the coupling agent includes one or more of 3-aminopropylethoxysiloxane, γ-glycidyloxypropyltrimethoxysilane, γ-(methacryloyloxy)propyltrimethoxysilane, dodecyltrimethoxysilane, vinyltriethoxysilane, titanate coupling agent, and aluminate coupling agent.

[0034] In one embodiment of the present application, the thermally conductive powder includes one or more of aluminum oxide, magnesium oxide, zinc oxide, aluminum nitride, boron nitride, silicon nitride, and silicon carbide.

[0035] In a specific implementation, several groups of high-temperature resistant thermally conductive silicone grease are prepared and compared with ordinary silicone grease.

[0036] Example 1:

[0037] 100 parts of methylphenyl silicone oil with a viscosity (25°C) of 100 mPa·s and a phenyl content of 25%, 400 parts of dodecyltrimethoxysilane-modified aluminum nitride, and 0.5 parts of cerium oxide were mixed at room temperature for 20 minutes, and then degassed and stirred at a vacuum degree of -0.08 MPa for 10 minutes to obtain the first group of high-temperature resistant thermal conductive silicone grease.

[0038] Example 2:

[0039] 100 parts of methylphenyl silicone oil with a viscosity (25°C) of 50 mPa·s and a phenyl content of 35%, 300 parts of boron nitride modified with a titanate coupling agent, and 1.5 parts of ferric oxide were mixed at room temperature for 25 minutes, and then degassed and stirred at a vacuum degree of -0.1 MPa for 5 minutes to obtain a second group of high-temperature resistant thermal conductive silicone grease.

[0040] Example 3:

[0041] 100 parts of methylphenyl silicone oil with a viscosity (25°C) of 500 mPa·s and a phenyl content of 50%, 600 parts of 3-aminopropylethoxysiloxane-modified alumina, and 3 parts of carbon black were mixed at room temperature for 30 minutes, and then degassed and stirred at a vacuum degree of -0.09 MPa for 8 minutes to obtain a third group of high-temperature resistant thermal conductive silicone grease.

[0042] Example 4:

[0043] 100 parts of methylphenyl silicone oil with a viscosity (25°C) of 150 mPa·s and a phenyl content of 35%, 1000 parts of dodecyltrimethoxysilane-modified alumina, and 2.5 parts of cerium oxide were mixed at room temperature for 25 minutes, and then degassed and stirred at a vacuum degree of -0.09 MPa for 6 minutes to obtain the fourth group of high-temperature resistant thermal conductive silicone grease.

[0044] Example 5:

[0045] 100 parts of methylphenyl silicone oil with a viscosity (25°C) of 150 mPa·s and a phenyl content of 35%, 300 parts of dodecyltrimethoxysilane-modified zinc oxide, 500 parts of dodecyltrimethoxysilane-modified aluminum oxide, and 3 parts of cerium oxide were mixed at room temperature for 30 minutes, and then degassed and stirred at a vacuum degree of -0.09 MPa for 8 minutes to obtain the fifth group of high-temperature resistant thermal conductive silicone grease.

[0046] The above embodiment is compared with the comparative example in terms of performance:

[0047] Comparative Example 1:

[0048] 100 parts of methyl silicone oil with a viscosity (25°C) of 150 mPa·s, 1000 parts of dodecyltrimethoxysilane-modified alumina, and 2.5 parts of cerium oxide were mixed at room temperature for 25 minutes, and then degassed and stirred at a vacuum degree of -0.09 MPa for 6 minutes to obtain thermal grease.

[0049] Comparative Example 2:

[0050] 100 parts of methylphenyl silicone oil with a viscosity (25° C.) of 150 mPa·s and a phenyl content of 35% and 1000 parts of dodecyltrimethoxysilane-modified alumina were mixed at room temperature for 25 minutes, and then degassed and stirred at a vacuum degree of -0.09 MPa for 6 minutes to obtain thermal grease.

[0051] The results of the comparison between the embodiment and the comparative example are shown in Table 1:

[0052]

[0053] The performance test methods are as follows:

[0054] Thermal conductivity: tested according to ISO22007-2 standard;

[0055] Cone penetration: tested according to GB / T269 standard;

[0056] High-temperature resistance test: Apply thermal grease evenly to a glass slide, creating a 0.2mm layer. Heat the grease to 200°C and bake for a fixed time. Observe the grease surface to see if it has dried. "Good" indicates a moist, smooth, and easy-to-apply surface. "Good" indicates a slightly dry surface, but a paste-like consistency within. "Poor" indicates a dry surface, but a paste-like consistency within. "NA" indicates the grease has completely powdered, and the test should be discontinued.

[0057] From the test results, it can be seen that compared with ordinary thermal grease and thermal grease without heat-resistant additives, the high-temperature resistant thermal grease proposed in this application has better high-temperature resistance.

[0058] In one embodiment of the present application, a method for preparing high-temperature resistant thermally conductive silicone grease is also provided, comprising the steps of:

[0059] S110, mixing and stirring methylphenyl silicone oil, modified thermally conductive powder, and a heat-resistant additive to obtain a premixed high-temperature resistant thermally conductive silicone grease; wherein the mixing ratio, by weight, is: 100 parts of methylphenyl silicone oil, 300-1000 parts of modified thermally conductive powder, and 0.5-3 parts of the heat-resistant additive;

[0060] S120, performing vacuum degassing treatment on the premixed high-temperature resistant thermally conductive silicone grease to obtain high-temperature resistant thermally conductive silicone grease.

[0061] It should be noted that the mixing and stirring can be carried out directly at room temperature, and then degassing is carried out by vacuum treatment.

[0062] In one embodiment of the present application, the method further includes preparing modified thermally conductive powder by using a coupling agent and thermally conductive powder.

[0063] It should be noted that the thermal conductive powder includes one or more of aluminum oxide, magnesium oxide, zinc oxide, aluminum nitride, boron nitride, silicon nitride, and silicon carbide; the coupling agent includes one or more of 3-aminopropylethoxysiloxane, γ-glycidyloxypropyltrimethoxysilane, γ-(methacryloyloxy)propyltrimethoxysilane, dodecyltrimethoxysilane, vinyltriethoxysilane, titanate coupling agent, and aluminate coupling agent.

[0064] In one embodiment of the present application, the step of preparing the modified thermally conductive powder by using a coupling agent and a thermally conductive powder includes:

[0065] Mix the thermal conductive powder, coupling agent and solvent according to the preset ratio and stir for 10-20 minutes;

[0066] Heat to 80-100°C and stir for 30-60 minutes to obtain a modified thermal conductive powder mixture;

[0067] The modified thermally conductive powder mixture is subjected to a vacuum desolventizing treatment to obtain the modified thermally conductive powder.

[0068] In one embodiment of the present application, the solvent is one of ethyl acetate or cyclohexanone.

[0069] In one embodiment of the present application, the mass ratio of the thermally conductive powder, the coupling agent, and the solvent is 100:1:50.

[0070] Although preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they become aware of the basic inventive concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0071] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or terminal device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or terminal device that includes the element.

[0072] The above is a detailed introduction to a high-temperature resistant thermal conductive silicone grease and a preparation method thereof provided by the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for general technical personnel in this field, based on the ideas of the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A high temperature resistant thermal conductive silicone grease, characterized in that: The composition comprises, by weight: 100 parts of methylphenyl silicone oil, 300-1000 parts of modified thermal conductive powder and 0.5-3 parts of heat-resistant additive; The viscosity of the methylphenyl silicone oil at 25° C. is 50-500 mPa·s, and the phenyl content of the methylphenyl silicone oil is 25-50%.

2. The high temperature resistant thermal conductive silicone grease according to claim 1, characterized in that: The heat-resistant additive is one or more of ferric oxide, cerium oxide, and carbon black.

3. The high temperature resistant thermal conductive silicone grease according to claim 1, characterized in that: The modified thermally conductive powder comprises a coupling agent and thermally conductive powder.

4. The high temperature resistant thermal conductive silicone grease according to claim 3, characterized in that: The coupling agent includes one or more of 3-aminopropylethoxysiloxane, γ-glycidyloxypropyltrimethoxysilane, γ-(methacryloyloxy)propyltrimethoxysilane, dodecyltrimethoxysilane, vinyltriethoxysilane, titanate coupling agent, and aluminate coupling agent.

5. The high temperature resistant thermal conductive silicone grease according to claim 1, characterized in that: The thermally conductive powder includes one or more of aluminum oxide, magnesium oxide, zinc oxide, aluminum nitride, boron nitride, silicon nitride, and silicon carbide.

6. A method for preparing high-temperature resistant thermally conductive silicone grease, characterized in that: Including steps: Mixing and stirring methylphenyl silicone oil, modified thermal conductive powder and heat-resistant additive to obtain a premixed high-temperature resistant thermal conductive silicone grease; wherein, based on parts by weight, the mixing ratio is: 100 parts of methylphenyl silicone oil, 300-1000 parts of modified thermal conductive powder, and 0.5-3 parts of heat-resistant additive; The premixed high-temperature resistant thermally conductive silicone grease is subjected to vacuum degassing treatment to obtain the high-temperature resistant thermally conductive silicone grease.

7. The preparation method according to claim 6, characterized in that Also includes: Modified thermal conductive powder is prepared by coupling agent and thermal conductive powder.

8. The preparation method according to claim 7, characterized in that The step of preparing the modified thermally conductive powder by using a coupling agent and thermally conductive powder comprises: Mix the thermal conductive powder, coupling agent and solvent according to the preset ratio and stir for 10-20 minutes; Heat to 80-100°C and stir for 30-60 minutes to obtain a modified thermal conductive powder mixture; The modified thermally conductive powder mixture is subjected to a vacuum desolventizing treatment to obtain the modified thermally conductive powder.

9. The preparation method according to claim 8, characterized in that The solvent is one of ethyl acetate or cyclohexanone.

10. The preparation method according to claim 8, characterized in that In terms of mass, the mass ratio of the thermally conductive powder, the coupling agent and the solvent is 100:1:50.

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