Demoldable heat-conducting pouring sealant as well as preparation method and application thereof

Abstract

The invention provides a releasable heat-conducting pouring sealant as well as a preparation method and application thereof. The preparation raw materials comprise a component A and a component B, the component A is prepared from 4 to 8 parts of vinyl silicone oil, 85 to 96 parts of heat-conducting filler, 0.2 to 0.8 part of dispersing agent, 0.03 to 0.05 part of catalyst and 0.6 to 1.3 parts of anti-settling slurry; the component B is prepared from the following components in parts by weight: 3 to 7 parts of vinyl silicone oil, 85 to 96 parts of heat-conducting filler, 0.2 to 0.8 part of dispersing agent, 0.1 to 1.0 part of hydrogen-containing resin, 0.007 to 0.060 part of polymerization inhibitor and 0.6 to 1.3 parts of anti-settling slurry. The heat-conducting filler is at least one of aluminum oxide, magnesium oxide and zinc oxide, and the particle size distribution width of the heat-conducting filler is less than or equal to 0.6. The anti-settling slurry is obtained by dispersing an anti-settling agent in vinyl silicone oil. The anti-settling agent is selected from boron nitride whiskers and / or carbon fibers. The vinyl silicone oil is a mixture of double-end vinyl fluorine-containing silicone oil and single-end vinyl fluorine-containing silicone oil. The heat-conducting pouring sealant has better strength, can be demoulded, has a heat conductivity coefficient of 6.0 W / mk or more, has lower viscosity, has better flowability and is difficult to settle.

Description

Technical Field

[0001] This invention relates to the field of potting compound technology, particularly to thermally conductive potting compounds, and even more particularly to releaseable thermally conductive potting compounds, their preparation methods, and their applications. Background Technology

[0002] Potting compounds are used for bonding, sealing, potting, and coating protection of electronic components. They are widely used in the electronics manufacturing industry and are an indispensable insulating material. In the rail transportation sector, high-performance power electronic modules are being designed to be increasingly smaller while their power consumption is increasing. Existing heat dissipation solutions, which only use thermal interface materials (TIMs) to transfer heat generated by the chip from one side to another, are no longer effective in solving the problem of localized heat accumulation within the module. Therefore, it is necessary to upgrade the surface-to-surface heat transfer solution to a surface-to-three-dimensional heat transfer solution. This requires a potting compound that can fill the entire module space, has high thermal conductivity matching that of TIMs, and can meet the requirements of low-viscosity injection molding to achieve three-dimensional heat transfer.

[0003] However, existing potting compounds are insufficient to meet the above requirements for the following reasons.

[0004] (1) The thermal conductivity of TIM material is above 6W / mk, while most of the existing potting compound materials have a thermal conductivity below 3W / mk, and a few can reach 4W / mk, which is difficult to match the TIM material requirements of above 6W / mk.

[0005] (2) The existing potting compound production process mostly involves high-speed stirring and shearing of metal machinery to fully disperse the thermally conductive filler in the liquid material. However, for highly filled and highly thermally conductive materials, this stirring-type high shearing will significantly increase the interaction force between powder particles, resulting in a significant increase in viscosity, or even thixotropy to form a paste, losing its fluidity function, and therefore cannot be used for injection potting molding in the module space.

[0006] Regarding point (1), although increasing the amount of thermally conductive filler can improve the thermal conductivity, increasing the amount of filler will bring many other performance defects, making it unusable. For example, with the increase of filler, the viscosity will rise or even lose fluidity, and the filler particles will increase in size and settle severely, making it impossible to mix evenly and use. The larger the amount of thermally conductive filler, the more severely the mechanical properties will be weakened, such as the strength will be poor and it will be easy to tear, it will not have good demolding properties, and it will not meet the manufacturing process of injection molding. In addition, the thermal conductivity can be improved by replacing traditional thermally conductive fillers with fillers with high thermal conductivity such as diamond and aluminum nitride, but the price of high thermal conductivity fillers such as diamond and aluminum nitride is several times or even tens of times that of ordinary thermally conductive fillers such as alumina and zinc oxide. Since the potting material itself is used in large quantities, it is particularly sensitive to cost control, which greatly limits its use.

[0007] Therefore, a high thermal conductivity potting compound that can be matched with TIM materials with a thermal conductivity of over 6W / mk, meets the requirements for low viscosity injection potting molding, has storage and anti-settling properties, is demoldable, and has controllable cost has become the key to solving the heat dissipation and manufacturing bottlenecks in this field. Summary of the Invention

[0008] To address the aforementioned issues, this invention provides a releaseable thermally conductive potting compound, its preparation method, and its application. This thermally conductive potting compound exhibits good strength and is releaseable, with a thermal conductivity exceeding 6.0 W / mk. It also has low viscosity, excellent flowability, and is resistant to settling. It can be injection molded and applied to power electronic working modules.

[0009] To achieve the above objectives, the present invention provides a releaseable thermally conductive potting compound, wherein the raw materials for preparation, by weight, include component A and component B. Component A comprises 4-8 parts of vinyl silicone oil, 85-96 parts of thermally conductive filler, 0.2-0.8 parts of dispersant, 0.03-0.05 parts of catalyst, and 0.6-1.3 parts of anti-settling slurry. Component B comprises 3-7 parts of the vinyl silicone oil, 85-96 parts of the thermally conductive filler, 0.2-0.8 parts of dispersant, and 0.1-1.0 parts of... The mixture comprises a hydrogen-containing resin, 0.007-0.060 parts of a polymerization inhibitor, and 0.6-1.3 parts of the anti-settling slurry; the thermally conductive filler is at least one selected from alumina, magnesium oxide, and zinc oxide, and the particle size distribution width of the thermally conductive filler is ≤0.6; the anti-settling slurry is obtained by dispersing an anti-settling agent in the vinyl silicone oil, the anti-settling agent being selected from boron nitride whiskers and / or carbon fibers; the vinyl silicone oil is a mixture of double-ended vinyl fluorinated silicone oil and single-ended vinyl fluorinated silicone oil; and the molecular formula of the hydrogen-containing resin is (R'SiO). 1.5 )8, where R' is -O((CH2CH2F)CH3SiO) nSi(CH3)2H, where n is any natural number from 1 to 20.

[0010] The releaseable thermally conductive potting compound of the present invention has at least the following beneficial effects.

[0011] (1) The thermally conductive potting compound of the present invention does not use expensive fillers with high thermal conductivity, such as diamond and aluminum nitride, but uses low-cost alumina, magnesium oxide and zinc oxide. The prepared thermally conductive potting compound avoids cost limitations and has great practicality and application prospects. In addition, the particle size distribution width of the thermally conductive filler is ≤0.6 and the particle size distribution of the thermally conductive powder is small, which can form better fluidity with anti-settling slurry, etc., so it can be potted and maintain better thermal conductivity.

[0012] (2) The vinyl silicone oil is a mixture of double-ended vinyl fluorinated silicone oil and single-ended vinyl fluorinated silicone oil. Through this mixture, fluorine groups with good release properties are introduced onto the vinyl silicone oil molecular chain, while (R'SiO) is used. 1.5 The hydrogen-containing resin (8) is a fluorine-modified cage-type hydrogen-containing resin, which has good compatibility with fluorinated vinyl silicone oil. Choosing this specific vinyl silicone oil and specific hydrogen-containing resin can significantly enhance the strength of the potting compound (thus eliminating the need for high-viscosity silicone oil or reinforcing agents to improve the compound's strength, avoiding the drawbacks of high-viscosity silicone oil or reinforcing agents increasing the potting compound's viscosity or even causing it to lose its fluidity). Therefore, it can increase strength without increasing viscosity or losing fluidity, thus enabling the prepared thermally conductive potting compound to meet the application requirements of mold release.

[0013] (3) Taking advantage of the high thermal conductivity and low density of boron nitride and carbon fiber, they are dispersed in vinyl silicone oil to form a slurry and then added to the potting compound. This has an excellent anti-settling effect, and at the same time, it can form a rapid thermal conduction path to improve the overall thermal conductivity, increase the tear resistance of the colloid and enhance the release properties. Moreover, adding it in the form of a slurry does not affect the flowability of the potting compound.

[0014] The thermally conductive potting compound of this invention, based on low-cost alumina, magnesium oxide, and zinc oxide, incorporates highly thermally conductive boron nitride and carbon fiber, achieving a thermal conductivity of over 6.0 W / mK. By selecting specific vinyl silicone oils and specific hydrogen-containing resins, and further combining the boron nitride and carbon fiber in the slurry, the strength of the potting compound can be improved without affecting its flowability, thus allowing for demolding and injection molding.

[0015] As one technical solution of the present invention, the fluorine content of the vinyl silicone oil is 5~30 mol%, and the viscosity is 30~150 cp.

[0016] As one technical solution of the present invention, the mass ratio of the dual-end vinyl fluorinated silicone oil to the single-end vinyl fluorinated silicone oil is 5:1~3.

[0017] As a technical solution of the present invention, the thermally conductive filler includes a first filler, a second filler, and a third filler. The first filler, the second filler, and the third filler have different particle size parameters. The first filler is spherical or near-spherical, and the sphericity of the spherical shape is greater than 0.97. The particle size of the first filler is 60~120μm, and the particle size distribution width of the first filler is 0.4~0.6. The second filler is spherical, and the sphericity of the spherical shape is greater than 0.95. The particle size of the second filler is 5~30μm, and the particle size distribution width of the second filler is 0.2~0.5. The third filler is spherical or angular, and the sphericity of the spherical shape is greater than 0.94. The particle size of the third filler is 0.1~3.0μm, and the particle size distribution width of the third filler is 0.05~0.20.

[0018] As one technical solution of the present invention, the thermally conductive filler is a mixture of alumina, magnesium oxide and zinc oxide, and the mass ratio of alumina, magnesium oxide and zinc oxide is 10:2~6:0.5~4.0.

[0019] As a technical solution of the present invention, the total content of sodium and iron ions in the thermally conductive filler is less than 200 ppm, and the pH value in the aqueous solution is 7±1.

[0020] As a technical solution of the present invention, the number average molecular weight of the dispersant is 2000~6000, and the structural formula of the dispersant is shown in structural formula I, wherein R is Si(OCH3)3, Si(OCH2CH3)3 or OH.

[0021]

[0022] Structural Formula I As one technical solution of the present invention, the catalyst is a Castells platinum catalyst with a concentration of 500~9000ppm.

[0023] As a technical solution of the present invention, the polymerization inhibitor is selected from at least one of 3-methyl-1-dodecyn-3-ol, methylbutynol, ethynylcyclohexanol, tetramethyldivinyldisiloxane and tetramethyltetravinylcyclotetrasiloxane. As a technical solution of the present invention, the functional slurry contains a dispersant, and the mass ratio of the vinyl silicone oil, the dispersant and the anti-settling agent is 1:0.1~0.4:0.5~2.0.

[0024] As a technical solution of the present invention, the number average molecular weight of the dispersant is 2000~6000, and the structural formula of the dispersant is shown in structural formula I, wherein R is Si(OCH3)3, Si(OCH2CH3)3 or OH.

[0025]

[0026] Structural Formula I As one technical solution of the present invention, the boron nitride whiskers are long whiskers with a length of 30~200μm.

[0027] As one technical solution of the present invention, the carbon fiber is a short-cut carbon fiber with a length of 50~200μm.

[0028] As a technical solution of the present invention, component A further includes 0.01 to 0.02 parts of color powder, wherein the color powder is selected from any one of carbon black, iron oxide red, iron oxide yellow, ultramarine blue and phthalocyanine blue.

[0029] A second aspect of the present invention provides a method for preparing a releaseable thermally conductive potting compound, comprising the steps of: ①Preparation of component A After mixing the vinyl silicone oil and the dispersant in a high-pressure gas flow dispersion vessel, dry air is introduced and each thermally conductive filler in the thermally conductive filler is added step by step. The temperature is raised and kept at a certain temperature for a certain time, then cooled to room temperature and the anti-settling slurry is added. After adding the catalyst and mixing, vacuum defoaming is performed. ②Preparation of component B After mixing the vinyl silicone oil and the dispersant in a high-pressure gas flow dispersion vessel, dry air is introduced and each thermally conductive filler in the thermally conductive filler is added step by step. The temperature is raised and held for a certain time, then cooled to room temperature and the hydrogen-containing resin and the anti-settling slurry are added. After adding the polymerization inhibitor and mixing, vacuum defoaming is performed.

[0030] In the preparation method of the releaseable thermally conductive potting compound of the present invention, both component A and component B are prepared by mixing and stirring in a high-pressure gas flow dispersion vessel, which replaces the traditional dispersion vessel with pure mechanical stirring. This avoids the situation where the viscosity of the system increases sharply or even loses its fluidity due to thixotropy caused by high-speed shearing of the central guide shaft and the highly filled thermally conductive filler particles.

[0031] As a technical solution of the present invention, the preparation of the anti-settling slurry includes the following steps: treating the vinyl silicone oil, the anti-settling agent and the dispersant with ultrasonic vibration according to the formula amount, heating and holding at a constant temperature for a certain period of time, and then dispersing them with a high-pressure homogenizer.

[0032] As one technical solution of the present invention, the ultrasonic power of the ultrasonic vibration is 500~1200W, the frequency is 20KHz, the time is 3~6min, the constant temperature is 50~70℃, the time is 4~9h, and the pressure of the high-pressure homogenizer is 900~1300bar.

[0033] A third aspect of the present invention provides the application of a releaseable thermally conductive potting compound in a power electronic working module, the power electronic working module comprising a thermal interface material and a chip, wherein the releaseable thermally conductive potting compound is injection molded in the power electronic working module. Detailed Implementation

[0034] The releaseable thermally conductive potting compound of this invention has good strength and is releaseable, with a thermal conductivity of over 6.0 W / mk, low viscosity, good flowability, and low sedimentation. This releaseable thermally conductive potting compound fills a power electronic working module, including thermal interface materials and chips, by injection molding to fill the entire module space. This transforms the heat transfer mode of the chip in the power electronic working module from surface-to-surface to surface-to-three-dimensional space, effectively solving the problem of localized heat accumulation in the module.

[0035] The raw materials for preparing the releaseable thermally conductive potting compound of the present invention include component A and component B.

[0036] The A component, by weight, comprises 4-8 parts of vinyl silicone oil, 85-96 parts of thermally conductive filler, 0.2-0.8 parts of dispersant, 0.03-0.05 parts of catalyst, and 0.6-1.3 parts of anti-settling slurry.

[0037] For example, the content of vinyl silicone oil may be, but is not limited to, 4 parts, 5 parts, 6 parts, 7 parts, or 8 parts. The fluorine content of the vinyl silicone oil is 5-30 mol%, for example, 5 mol%, 10 mol%, 15 mol%, 20 mol%, 25 mol%, or 30 mol%. The viscosity is 30-150 cp, for example, 30 cp, 40 cp, 50 cp, 60 cp, 70 cp, 80 cp, 90 cp, 100 cp, 110 cp, 120 cp, 130 cp, 140 cp, or 150 cp. The vinyl silicone oil is a mixture of double-ended vinyl fluorinated silicone oil and single-ended vinyl fluorinated silicone oil. The mass ratio of double-ended vinyl fluorinated silicone oil to single-ended vinyl fluorinated silicone oil is 5:1 to 3, for example, 5:1, 5:2, or 5:3.

[0038] The content of the thermally conductive filler may be, but is not limited to, 85 parts, 86 parts, 87 parts, 88 parts, 89 parts, 90 parts, 91 parts, 92 parts, 93 parts, 94 parts, 95 parts, and 96 parts. The thermally conductive filler is at least one of alumina, magnesium oxide, and zinc oxide, and the particle size distribution width of the thermally conductive filler is ≤0.6. Further, the thermally conductive filler is a mixture of alumina, magnesium oxide, and zinc oxide. The alumina is spherical or near-spherical, with a sphericity greater than 0.97, a particle size of 60~120μm, and a particle size distribution width of 0.4~0.6. The magnesium oxide is spherical, with a sphericity greater than 0.95, a particle size of 5~30μm, and a particle size distribution width of 0.2~0.5. Zinc oxide is spherical or angular, with a sphericity greater than 0.94 for spherical particles. The particle size ranges from 0.1 to 3.0 μm, and the particle size distribution width is 0.05 to 0.20. The thermally conductive filler is a mixture of alumina, magnesium oxide, and zinc oxide, with a mass ratio of 10:2 to 6:0.5 to 4.0. The total sodium and iron ion content in the thermally conductive filler is less than 200 ppm, and the pH value in aqueous solution is 7 ± 1.

[0039] The content of the dispersant may be, but is not limited to, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, or 0.8 parts. The number average molecular weight of the dispersant is 2000~6000, and the structural formula of the dispersant is shown in structural formula I, where R is Si(OCH3)3, Si(OCH2CH3)3, or OH.

[0040]

[0041] Structural Formula I The catalyst content may be, but is not limited to, 0.03 parts, 0.04 parts, or 0.05 parts. The catalyst is a platinum catalyst, more preferably a caster platinum catalyst, and the concentration is 500~9000 ppm. For example, the concentration may be, but is not limited to, 500 ppm, 1000 ppm, 1500 ppm, 2000 ppm, 2500 ppm, 3000 ppm, 3500 ppm, 4000 ppm, 4500 ppm, 5000 ppm, 5500 ppm, 6000 ppm, 6500 ppm, 7000 ppm, 7500 ppm, 8000 ppm, 8500 ppm, or 9000 ppm.

[0042] The content of the anti-settling slurry may be, but is not limited to, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1.0 parts, 1.1 parts, 1.2 parts, or 1.3 parts. The anti-settling slurry is obtained by dispersing an anti-settling agent in vinyl silicone oil. The anti-settling agent is selected from boron nitride whiskers and / or carbon fibers. The boron nitride whiskers are long and whisker-like with a length of 30-200 μm. For example, the length may be, but is not limited to, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 120 μm, 140 μm, 160 μm, 180 μm, or 200 μm. The carbon fiber is a short-cut carbon fiber with a length of 50~200μm. For example, the length may be, but is not limited to, 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, 120μm, 140μm, 160μm, 180μm, and 200μm. Furthermore, the functional slurry also contains a dispersant, and the mass ratio of vinyl silicone oil, dispersant, and anti-settling agent is 1:0.1~0.4:0.5~2.0. For example, the mass ratio may be, but is not limited to, 1:0.1:0.5, 1:0.2:0.5, 1:0.3:0.5, 1:0.4:0.5, 1:0.1:1.0, 1:0.2:1.0, 1:0.3:1.0, 1:0.4:1.0, 1:0.1:1.5, 1:0.2:1.5, 1:0.3:1.5, 1:0.4:1.5, 1:0.1:2.0, 1:0.2:2.0, 1:0.3:2.0, and 1:0.4:2.0. The vinyl silicone oil is the same as the vinyl silicone oil in component A mentioned above, and is a mixture of double-ended vinyl fluorinated silicone oil and single-ended vinyl fluorinated silicone oil. The mass ratio of the double-ended vinyl fluorinated silicone oil to the single-ended vinyl fluorinated silicone oil is 5:1 to 3. For example, the mass ratio may be, but is not limited to, 5:1, 5:2, or 5:3. The dispersant is also the same as the dispersant in component A mentioned above, with a number average molecular weight of 2000 to 6000. The structural formula of the dispersant is shown in structural formula I, where R is Si(OCH3)3, Si(OCH2CH3)3, or OH.

[0043]

[0044] Structural Formula I Component A may further include 0.01 to 0.02 parts of pigment. For example, the amount of pigment may be, but is not limited to, 0.010 parts, 0.011 parts, 0.012 parts, 0.013 parts, 0.014 parts, 0.015 parts, 0.016 parts, 0.017 parts, 0.018 parts, 0.019 parts, or 0.020 parts. The pigment is selected from any one of carbon black, iron oxide red, iron oxide yellow, ultramarine blue, and phthalocyanine blue.

[0045] Component B includes 3-7 parts of vinyl silicone oil, 85-96 parts of thermally conductive filler, 0.2-0.8 parts of dispersant, 0.1-1.0 parts of hydrogen-containing resin, 0.007-0.060 parts of polymerization inhibitor, and 0.6-1.3 parts of anti-settling slurry.

[0046] For example, the content of vinyl silicone oil may be, but is not limited to, 3 parts, 4 parts, 5 parts, 6 parts, or 7 parts. The fluorine content of the vinyl silicone oil is 5 to 30 parts, for example, it may be, but is not limited to, 5 parts, 10 parts, 15 parts, 20 parts, 25 parts, or 30 parts. The viscosity is 30 to 150 cp, for example, it may be, but is not limited to, 30 cp, 40 cp, 50 cp, 60 cp, 70 cp, 80 cp, 90 cp, 100 cp, 110 cp, 120 cp, 130 cp, 140 cp, or 150 cp. The vinyl silicone oil is a mixture of double-ended vinyl fluorinated silicone oil and single-ended vinyl fluorinated silicone oil. The mass ratio of double-ended vinyl fluorinated silicone oil to single-ended vinyl fluorinated silicone oil is 5:1 to 3, for example, it may be, but is not limited to, 5:1, 5:2, or 5:3.

[0047] The content of the thermally conductive filler may be, but is not limited to, 85 parts, 86 parts, 87 parts, 88 parts, 89 parts, 90 parts, 91 parts, 92 parts, 93 parts, 94 parts, 95 parts, and 96 parts. The thermally conductive filler is at least one of alumina, magnesium oxide, and zinc oxide; further, the thermally conductive filler is a mixture of alumina, magnesium oxide, and zinc oxide, and the mass ratio of alumina, magnesium oxide, and zinc oxide is 10:2~6:0.5~4.0. The total content of sodium and iron ions in the thermally conductive filler is less than 200 ppm, and the pH value in the aqueous solution is 7±1. From a particle perspective, the thermally conductive filler may include a first filler, a second filler, and a third filler. The particle size parameters of the first filler, the second filler, and the third filler are different. The first filler is spherical or near-spherical, and the sphericity is greater than 0.97; the particle size of the first filler is 60~120 μm; and the particle size distribution width of the first filler is 0.4~0.6. The second packing material is spherical with a sphericity greater than 0.95, a particle size of 5–30 μm, and a particle size distribution width of 0.2–0.5. The third packing material is spherical or angular with a sphericity greater than 0.94, a particle size of 0.1–3.0 μm, and a particle size distribution width of 0.05–0.20. The first, second, and third packing materials have different particle size parameters, and their materials can be independently at least one of alumina, magnesium oxide, and zinc oxide.

[0048] The content of the dispersant may be, but is not limited to, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, or 0.8 parts. The number average molecular weight of the dispersant is 2000~6000, and the structural formula of the dispersant is shown in structural formula I, where R is Si(OCH3)3, Si(OCH2CH3)3, or OH.

[0049]

[0050] Structural Formula I The content of hydrogen-containing resin can be, but is not limited to, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, and 1.0 parts. The molecular formula of the hydrogen-containing resin is (R'SiO). 1.5 )8, where R' is -O((CH2CH2F)CH3SiO) n Si(CH3)2H, where n is any natural number from 1 to 20.

[0051] The content of the polymerization inhibitor may be, but is not limited to, 0.007 parts, 0.010 parts, 0.015 parts, 0.020 parts, 0.025 parts, 0.030 parts, 0.035 parts, 0.040 parts, 0.045 parts, 0.050 parts, 0.055 parts, or 0.060 parts. The polymerization inhibitor is selected from at least one of 3-methyl-1-dodecyn-3-ol, methylbutynol, ethynylcyclohexanol, tetramethyldivinyldisiloxane, and tetramethyltetravinylcyclotetrasiloxane. The content of the anti-settling slurry may be, but is not limited to, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1.0 parts, 1.1 parts, 1.2 parts, or 1.3 parts. The anti-settling slurry is obtained by dispersing an anti-settling agent in vinyl silicone oil. The anti-settling agent is selected from boron nitride whiskers and / or carbon fibers. The boron nitride whiskers are long and whisker-like with a length of 30-200 μm. For example, the length may be, but is not limited to, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 120 μm, 140 μm, 160 μm, 180 μm, or 200 μm. The carbon fiber is a short-cut carbon fiber with a length of 50~200μm. For example, the length may be, but is not limited to, 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, 120μm, 140μm, 160μm, 180μm, and 200μm. Furthermore, the functional slurry also contains a dispersant, and the mass ratio of vinyl silicone oil, dispersant, and anti-settling agent is 1:0.1~0.4:0.5~2.0. For example, the mass ratio may be, but is not limited to, 1:0.1:0.5, 1:0.2:0.5, 1:0.3:0.5, 1:0.4:0.5, 1:0.1:1.0, 1:0.2:1.0, 1:0.3:1.0, 1:0.4:1.0, 1:0.1:1.5, 1:0.2:1.5, 1:0.3:1.5, 1:0.4:1.5, 1:0.1:2.0, 1:0.2:2.0, 1:0.3:2.0, and 1:0.4:2.0. The vinyl silicone oil is the same as the vinyl silicone oil in component A mentioned above, and is a mixture of double-ended vinyl fluorinated silicone oil and single-ended vinyl fluorinated silicone oil. The mass ratio of the double-ended vinyl fluorinated silicone oil to the single-ended vinyl fluorinated silicone oil is 5:1 to 3. For example, the mass ratio may be, but is not limited to, 5:1, 5:2, or 5:3. The dispersant is also the same as the dispersant in component A mentioned above, with a number average molecular weight of 2000 to 6000. The structural formula of the dispersant is shown in structural formula I, where R is Si(OCH3)3, Si(OCH2CH3)3, or OH.

[0052]

[0053] Structural Formula I The method for preparing the releaseable thermally conductive potting compound of the present invention may include the following steps.

[0054] ①Preparation of component A After mixing vinyl silicone oil and dispersant in a high-pressure gas flow dispersion vessel, dry air is introduced and each thermally conductive filler is added step by step. The mixture is heated and kept at that temperature for a certain period of time, then cooled to room temperature and anti-settling slurry is added. After adding catalyst and mixing, vacuum defoaming is performed.

[0055] ②Preparation of component B After mixing vinyl silicone oil and dispersant in a high-pressure gas flow dispersion vessel, dry air is introduced and each thermally conductive filler is added step by step. The mixture is heated and kept at that temperature for a certain period of time, then cooled to room temperature and hydrogen-containing resin and anti-settling slurry are added. After adding polymerization inhibitor and mixing, vacuum defoaming is performed.

[0056] Furthermore, in the preparation of component A, the parameters of the high-pressure gas dispersion vessel can be set the same or different when adding each component. Each time a component is added, a certain amount of drying gas is first introduced, then the gas flow is stopped. The gas flow is restarted after the other components are added. When adding the thermally conductive filler, the smaller-sized zinc oxide is added first, followed by magnesium oxide, and finally the larger-sized alumina. If the thermally conductive filler only includes two of these types, it can be added in two steps, with the smaller-sized filler added first, followed by the larger-sized filler, to ensure uniform mixing.

[0057] Specifically, the preparation steps for component A are as follows: Vinyl silicone oil and dispersant are added to a high-pressure gas flow dispersion vessel by weight. Dry air is introduced through the gas flow valve at a flow rate of 5-10 m / s. The central guide shaft is started to rotate at a speed of 5-10 r / min. After dispersion for 3-9 minutes, the gas flow valve is closed, and the rotation of the central guide shaft is stopped. Zinc oxide from the thermally conductive filler is added to the high-pressure gas flow dispersion vessel by weight. Dry air is introduced through the gas flow valve at a flow rate of 10-30 m / s. The central guide shaft is started to rotate. The flow axis rotates at a speed of 10-20 r / min, and after dispersion for 20-40 min, the airflow switch valve is closed, and the rotation of the central guide shaft is stopped. Magnesium oxide from the thermally conductive packing is added to the high-pressure airflow dispersion vessel by weight. Dry air is introduced through the airflow switch valve at a flow rate of 10-30 m / s. The central guide shaft rotates at a speed of 10-20 r / min, and after dispersion for 20-40 min, the airflow switch valve is closed, and the rotation of the central guide shaft is stopped. Aluminum oxide from the thermally conductive packing is added to the high-pressure airflow dispersion vessel by weight. In the dispersion vessel, open the airflow valve to introduce dried air at a flow rate of 10-30 m / s, and start the central guide shaft to rotate at a speed of 10-20 r / min, dispersing for 60-120 min. Heat the material to 60-90℃, hold for 30-90 min, then close the airflow valve and the central guide shaft to allow the material temperature to drop to room temperature. Add the color powder and anti-settling slurry to the high-pressure airflow dispersion vessel by weight, open the airflow valve to introduce dried air at a flow rate of 10-30 m / s, and start the central guide shaft to rotate at a speed of 10-20 r / min, dispersing for 60-120 min. The flow axis rotates at a speed of 10~20 r / min. After dispersion for 20~40 min, the gas flow switch valve is closed, and the rotation of the central guide shaft is stopped. The catalyst is added to the high-pressure gas flow dispersion vessel by weight. The gas flow switch valve is opened to introduce dried air at a flow rate of 10~30 m / s. The central guide shaft is started to rotate at a speed of 10~20 r / min. After dispersion for 5~15 min, the gas flow switch valve is closed, and the rotation of the central guide shaft is stopped. Vacuum degassing is started for 10~20 min, and the vacuum degree is less than -0.08 MPa.

[0058] In the preparation of component B, the parameters of the high-pressure gas dispersion vessel can be set the same or different when adding each component. Each time a component is added, a certain amount of drying gas is first introduced, then the gas flow is turned off. The gas flow is restarted after the other components are added. When adding the thermally conductive filler, zinc oxide with the smaller particle size is added first, followed by magnesium oxide, and finally aluminum oxide with the larger particle size. If the thermally conductive filler includes only two of these two types, it can be added in two steps, with the smaller particle size filler added first, followed by the larger particle size filler, to ensure uniform mixing.

[0059] Specifically, the preparation steps for component B are as follows: Vinyl silicone oil and dispersant are added to a high-pressure gas flow dispersion vessel by weight. Dry air is introduced through the gas flow valve at a flow rate of 5-10 m / s. The central guide shaft is started to rotate at a speed of 5-10 r / min. After dispersion for 3-9 minutes, the gas flow valve is closed, and the rotation of the central guide shaft is stopped. Zinc oxide from the thermally conductive filler is added to the high-pressure gas flow dispersion vessel by weight. Dry air is introduced through the gas flow valve at a flow rate of 10-30 m / s. The central guide shaft is started to rotate. The flow axis rotates at a speed of 10-20 r / min. After dispersion for 20-40 minutes, the airflow switch valve is closed, and the rotation of the central guide shaft is stopped. Magnesium oxide from the thermally conductive packing is added to the high-pressure airflow dispersion vessel by weight. Dry air is introduced through the airflow switch valve at a flow rate of 10-30 m / s. The central guide shaft rotates at a speed of 10-20 r / min. After dispersion for 20-40 minutes, the airflow switch valve is closed, and the rotation of the central guide shaft is stopped. Aluminum oxide from the thermally conductive packing is added to the high-pressure airflow dispersion vessel by weight. In the reactor, open the gas flow valve to introduce dried air at a flow rate of 10-30 m / s, and start the central guide shaft to rotate at a speed of 10-20 r / min, dispersing for 60-120 min. Heat the material to 60-90℃, hold for 30-90 min, then close the gas flow valve and the central guide shaft to allow the material temperature to drop to room temperature. Measure the weight of the hydrogen-containing resin and anti-settling slurry into the high-pressure gas flow dispersion reactor, open the gas flow valve to introduce dried air at a flow rate of 10-30 m / s, and start the central guide shaft to rotate. The guide shaft rotates at a speed of 10~20 r / min. After dispersion for 20~40 min, the gas flow switch valve is closed, and the rotation of the central guide shaft is stopped. The polymerization inhibitor is added to the high-pressure gas flow dispersion vessel by weight. The gas flow switch valve is opened to introduce dried air at a flow rate of 10~30 m / s. The central guide shaft is started to rotate at a speed of 10~20 r / min. After dispersion for 5~15 min, the gas flow switch valve is closed, and the rotation of the central guide shaft is stopped. Vacuum degassing is started for 10~20 min, and the vacuum degree is less than -0.08 MPa.

[0060] In addition, the preparation of anti-settling slurry may include the following steps: treating vinyl silicone oil, anti-settling agent, and dispersant with ultrasonic vibration according to the formula, heating and maintaining a constant temperature for a certain period of time, and then dispersing using a high-pressure homogenizer. Boron nitride whiskers and carbon fibers, due to capillary forces, electrostatic forces, and even entanglement between particles, and because both substances have very low density and are subject to little gravitational force, when these forces between particles exceed the particle's weight, the particle behavior is largely no longer constrained by gravity, and the particles tend to aggregate. Therefore, most boron nitride whiskers and carbon fibers exist in bundles or even clumps. Traditional dispersion processes for making boron nitride whiskers and carbon fibers into slurries mostly involve ordinary stirring or ultrasonic dispersion, but the dispersion effect is not ideal, and stable deagglomeration cannot be achieved, failing to meet the requirements for preparing potting compounds with a thermal conductivity of 6 W / mK. The anti-settling slurry of this invention is prepared by using ultrasonic vibration combined with a high-pressure homogenizer and adding a special dispersant. The boron nitride whiskers and carbon fibers are subjected to strong impact, pressure difference and cavitation in the high-pressure homogenizer, so that most of the particles in the boron nitride whiskers and carbon fibers are stablely separated from the agglomerated bundles and blocks, thus overcoming the defect that filamentous boron nitride and carbon fibers are easy to agglomerate and difficult to disperse, thereby preparing a uniformly dispersed functional slurry. Therefore, when added to the potting compound, it is evenly dispersed and can effectively exert its thermal conductivity and anti-settling effect.

[0061] Furthermore, the ultrasonic vibration power is 500~1200W, the frequency is 20KHz, the duration is 3~6min, the constant temperature is 50~70℃, the duration is 4~9h, and the pressure of the high-pressure homogenizer is 900~1300bar. The pressure of the high-pressure homogenizer should not be too low, otherwise the depolymerization effect cannot be achieved, that is, the filamentous boron nitride whiskers and carbon fibers cannot be stably separated from the agglomerates. If the pressure is too high, the separated filaments may re-enter agglomerates or even be broken, which also fails to achieve effective depolymerization.

[0062] To better illustrate the purpose, technical solution, and beneficial effects of this invention, the invention will be further described below with reference to specific embodiments. It should be noted that the methods described below are further explanations of this invention and should not be construed as limiting it.

[0063] Example 1 This embodiment describes a releaseable thermally conductive potting compound, prepared from components A and B. Component A comprises 8 parts vinyl silicone oil, 91.13 parts thermally conductive filler, 0.2 parts dispersant, 0.05 parts catalyst, 0.02% colorant, and 0.6 parts anti-settling slurry. Component B comprises 7 parts vinyl silicone oil, 91.193 parts thermally conductive filler, 0.2 parts dispersant, 1.0 part hydrogen-containing resin, 0.007 parts polymerization inhibitor, and 0.6 parts anti-settling slurry. The anti-settling slurry is obtained by dispersing the anti-settling agent in vinyl silicone oil.

[0064] The functional slurries in components A and B are prepared from vinyl silicone oil, a dispersant, and boron nitride whiskers in a mass ratio of 1:0.4:2.0. The boron nitride whiskers are long and 200 μm in length. The vinyl silicone oil in components A, B, and the anti-settling slurry has a fluorine content of 5 mol% and a viscosity of 30 cp. The vinyl silicone oil is a mixture of double-ended vinyl fluorinated silicone oil and single-ended vinyl fluorinated silicone oil in a mass ratio of 5:1. The dispersant in components A, B, and the anti-settling slurry has the structural formula shown in Structural Formula I, with a number average molecular weight of 4000~5000, and R is Si(OCH3)3.

[0065]

[0066] Structural Formula I The thermally conductive fillers in components A and B are mixtures of alumina, magnesium oxide, and zinc oxide. The total sodium and iron ion content in the thermally conductive fillers is less than 200 ppm, and the pH value is 7 ± 1. The mass ratio of alumina, magnesium oxide, and zinc oxide is 10:2:4. The alumina is spherical with a particle size of 120 μm (sphericity greater than 0.97) and a particle size distribution width of 0.4–0.6. The magnesium oxide is spherical with a particle size of 30 μm and a particle size distribution width of 0.2–0.5. The zinc oxide is near-spherical alumina with a particle size of 0.1 μm and a particle size distribution width of 0.05–0.20.

[0067] The catalyst in component A is a Castrol platinum catalyst with a concentration of 9000 ppm, and the pigment is carbon black.

[0068] The molecular formula of the hydrogen-containing resin in component B is (R'SiO). 1.5 )8, where R' is -O((CH2CH2F)CH3SiO) 20 Si(CH3)2H. The polymerization inhibitor is 3-methyl-1-dodecyn-3-ol.

[0069] The method for preparing the releaseable thermally conductive potting compound in this embodiment includes the following steps: (1) The preparation of anti-settling slurry may include the following steps: placing vinyl silicone oil, dispersant and boron nitride whiskers in an open container, premixing them with an ultrasonic vibrator for 6 minutes, with an ultrasonic power of 1200W and a frequency of 20KHz; placing them in a 70℃ constant temperature oven for 4 hours and then taking them out; pouring them into a high pressure homogenizer for dispersion, setting the pressure to 1300bar, to obtain anti-settling slurry.

[0070] (2) The preparation steps of component A can be as follows: Add vinyl silicone oil and dispersant to a high-pressure gas flow dispersion vessel by weight, open the gas flow valve to introduce dried air at a flow rate of 5 m / s, start the central guide shaft to rotate at a speed of 5 r / min, disperse for 9 min, then close the gas flow valve and stop the rotation of the central guide shaft; Add zinc oxide from the thermally conductive filler to a high-pressure gas flow dispersion vessel by weight, open the gas flow valve to introduce dried air at a flow rate of 10 m / s, start the central guide shaft to rotate at a speed of 10 r / min, disperse for 40 min, then close the gas flow valve and stop the rotation of the central guide shaft; Add magnesium oxide from the thermally conductive filler to a high-pressure gas flow dispersion vessel by weight, open the gas flow valve to introduce dried air at a flow rate of 10 m / s, start the central guide shaft to rotate at a speed of 10 r / min, disperse for 40 min, then close the gas flow valve and stop the rotation of the central guide shaft; Add alumina from the thermally conductive filler to a high-pressure gas flow dispersion vessel by weight... In the high-pressure airflow dispersion vessel, open the airflow valve to introduce dried air at a flow rate of 10 m / s, and start the central guide shaft to rotate at a speed of 10 r / min for 120 min. Heat the material to 60℃, hold for 90 min, then close the airflow valve and the central guide shaft to allow the material temperature to return to room temperature. Add the color powder and anti-settling slurry to the high-pressure airflow dispersion vessel by weight, open the airflow valve to introduce dried air at a flow rate of 10 m / s, and start the central guide shaft to rotate for 120 min. The central guide shaft rotates at a speed of 10 r / min. After dispersion for 40 min, the gas flow switch valve is closed, and the rotation of the central guide shaft is stopped. The catalyst is added to the high-pressure gas flow dispersion vessel by weight. The gas flow switch valve is opened to introduce dried air at a flow rate of 10 m / s. The central guide shaft is started to rotate at a speed of 10 r / min. After dispersion for 15 min, the gas flow switch valve is closed, and the rotation of the central guide shaft is stopped. Vacuum degassing is started for 10 min, and the vacuum degree is less than -0.08 MPa.

[0071] (3) The preparation steps of component B are as follows: Add vinyl silicone oil and dispersant to a high-pressure gas flow dispersion vessel by weight, open the gas flow switch valve to introduce dried air at a flow rate of 5 m / s, start the central guide shaft to rotate at a speed of 5 r / min, disperse for 9 min, then close the gas flow switch valve and stop the rotation of the central guide shaft; Add zinc oxide from the thermally conductive filler to a high-pressure gas flow dispersion vessel by weight, open the gas flow switch valve to introduce dried air at a flow rate of 10 m / s, start the central guide shaft to rotate at a speed of 10 r / min, disperse for 40 min, then close the gas flow switch valve and stop the rotation of the central guide shaft; Add magnesium oxide from the thermally conductive filler to a high-pressure gas flow dispersion vessel by weight, open the gas flow switch valve to introduce dried air at a flow rate of 10 m / s, start the central guide shaft to rotate at a speed of 10 r / min, disperse for 40 min, then close the gas flow switch valve and stop the rotation of the central guide shaft; Add alumina from the thermally conductive filler to a high-pressure gas flow dispersion vessel by weight. In the gas-flow dispersion vessel, open the gas flow valve to introduce dried air at a flow rate of 10 m / s, and start the central guide shaft to rotate at a speed of 10 r / min for 120 min. Heat the material to 60℃, hold for 90 min, then close the gas flow valve and the central guide shaft to allow the material temperature to return to room temperature. Add the hydrogen-containing resin and anti-settling slurry to the high-pressure gas-flow dispersion vessel by weight, open the gas flow valve to introduce dried air at a flow rate of 10 m / s, and start the gas flow dispersion vessel. The central guide shaft rotates at a speed of 10 r / min. After dispersion for 40 min, the gas flow switch valve is closed, and the rotation of the central guide shaft is stopped. The polymerization inhibitor is added to the high-pressure gas flow dispersion vessel by weight. The gas flow switch valve is opened to introduce dried air at a flow rate of 10 m / s. The central guide shaft is started to rotate at a speed of 10 r / min. After dispersion for 15 min, the gas flow switch valve is closed, and the rotation of the central guide shaft is stopped. Vacuum degassing is started for 10 min, and the vacuum degree is less than -0.08 MPa.

[0072] Example 2 This embodiment describes a releaseable thermally conductive potting compound, prepared from components A and B. Component A comprises 5 parts vinyl silicone oil, 93.25 parts thermally conductive filler, 0.8 parts dispersant, 0.04 parts catalyst, 0.01% colorant, and 0.9 parts anti-settling slurry. Component B comprises 4 parts vinyl silicone oil, 93.980 parts thermally conductive filler, 0.5 parts dispersant, 0.5 parts hydrogen-containing resin, 0.020 parts polymerization inhibitor, and 1.0 part anti-settling slurry. The anti-settling slurry is obtained by dispersing the anti-settling agent in vinyl silicone oil.

[0073] The functional slurry in components A and B is prepared from vinyl silicone oil, a dispersant, and carbon fiber in a mass ratio of 1:0.2:1.0. The carbon fiber is short-cut carbon fiber with a length of 100 μm. The vinyl silicone oil in components A, B, and the anti-settling slurry has a fluorine content of 20 mol% and a viscosity of 100 cp. The vinyl silicone oil is a mixture of double-ended vinyl fluorinated silicone oil and single-ended vinyl fluorinated silicone oil in a mass ratio of 5:3. The dispersant in components A, B, and the anti-settling slurry has the structural formula shown in Structural Formula I, with a number average molecular weight of 3500~4500, where R represents OH.

[0074]

[0075] Structural Formula I The thermally conductive fillers in components A and B are mixtures of alumina and zinc oxide. The total sodium and iron ion content in the thermally conductive filler impurities is less than 200 ppm, and the pH value is 7 ± 1. The mass ratio of alumina to zinc oxide is 10:2.5. The alumina is spherical with a particle size of 100 μm (sphericity greater than 0.97) and a particle size distribution width of 0.4–0.6. The zinc oxide is near-spherical with a particle size of 2.0 μm and a particle size distribution width of 0.05–0.15.

[0076] The catalyst in component A is a Castells platinum catalyst with a concentration of 5000 ppm, and the colorant is ultramarine blue.

[0077] The molecular formula of the hydrogen-containing resin in component B is (R'SiO). 1.5 )8, where R' is -O((CH2CH2F)CH3SiO) 15 Si(CH3)2H. The polymerization inhibitor is tetramethyltetravinylcyclotetrasiloxane.

[0078] The method for preparing the releaseable thermally conductive potting compound in this embodiment includes the following steps: (1) The preparation of anti-settling slurry may include the following steps: placing vinyl silicone oil, dispersant and carbon fiber in an open container, premixing with an ultrasonic vibrator for 4 min, with an ultrasonic power of 800 W and a frequency of 15 KHz; placing in a constant temperature oven at 55℃ for 8 h and then taking it out; pouring it into a high pressure homogenizer for dispersion, setting the pressure to 1000 bar, to obtain anti-settling slurry.

[0079] (2) The preparation steps of component A can be as follows: Add vinyl silicone oil and dispersant to a high-pressure gas flow dispersion vessel by weight, open the gas flow switch valve to introduce dried air at a flow rate of 8 m / s, start the central guide shaft to rotate at a speed of 9 r / min, disperse for 5 min, then close the gas flow switch valve and stop the rotation of the central guide shaft; Add zinc oxide from the thermally conductive filler to a high-pressure gas flow dispersion vessel by weight, open the gas flow switch valve to introduce dried air at a flow rate of 25 m / s, start the central guide shaft to rotate at a speed of 15 r / min, disperse for 30 min, then close the gas flow switch valve and stop the rotation of the central guide shaft; Add alumina from the thermally conductive filler to a high-pressure gas flow dispersion vessel by weight, open the gas flow switch valve to introduce dried air at a flow rate of 20 m / s, start the central guide shaft to rotate at a speed of 15 r / min. Disperse for 80 minutes; heat the material to 80℃, hold for 60 minutes, then close the gas flow valve and stop the rotation of the central guide shaft, allowing the material temperature to return to room temperature; add the color powder and anti-settling slurry to the high-pressure gas flow dispersion vessel by weight, open the gas flow valve to introduce dried air at a flow rate of 25 m / s, start the rotation of the central guide shaft at 15 r / min, disperse for 30 minutes, then close the gas flow valve and stop the rotation of the central guide shaft; add the catalyst to the high-pressure gas flow dispersion vessel by weight, open the gas flow valve to introduce dried air at a flow rate of 30 m / s, start the rotation of the central guide shaft at 15 r / min, disperse for 10 minutes, then close the gas flow valve and stop the rotation of the central guide shaft; start vacuum degassing for 15 minutes, achieving a vacuum level of less than -0.08 MPa.

[0080] (3) The preparation steps of component B are as follows: Add vinyl silicone oil and dispersant to a high-pressure gas flow dispersion vessel by weight, open the gas flow valve to introduce dried air at a flow rate of 10 m / s, start the central guide shaft to rotate at a speed of 8 r / min, disperse for 4 min, then close the gas flow valve and stop the rotation of the central guide shaft; Add zinc oxide from the thermally conductive filler to a high-pressure gas flow dispersion vessel by weight, open the gas flow valve to introduce dried air at a flow rate of 25 m / s, start the central guide shaft to rotate at a speed of 15 r / min, disperse for 30 min, then close the gas flow valve and stop the rotation of the central guide shaft; Add alumina from the thermally conductive filler to a high-pressure gas flow dispersion vessel by weight, open the gas flow valve to introduce dried air at a flow rate of 25 m / s, start the central guide shaft to rotate at a speed of 20 r / min. Disperse for 80 minutes; heat the material to 80℃, hold for 60 minutes, then close the gas flow valve and the central guide shaft rotation, and allow the material temperature to return to room temperature; add the hydrogen-containing resin and anti-settling slurry to the high-pressure gas flow dispersion vessel by weight, open the gas flow valve to introduce dried air at a flow rate of 20 m / s, start the central guide shaft rotation at a speed of 15 r / min, disperse for 30 minutes, then close the gas flow valve and the central guide shaft rotation; add the polymerization inhibitor to the high-pressure gas flow dispersion vessel by weight, open the gas flow valve to introduce dried air at a flow rate of 20 m / s, start the central guide shaft rotation at a speed of 15 r / min, disperse for 10 minutes, then close the gas flow valve and the central guide shaft rotation; activate vacuum degassing for 15 minutes, achieving a vacuum level of less than -0.08 MPa.

[0081] Example 3 This embodiment describes a releaseable thermally conductive potting compound, prepared from components A and B. Component A comprises 7 parts vinyl silicone oil, 90.94 parts thermally conductive filler, 0.8 parts dispersant, 0.04 parts catalyst, 0.02% colorant, and 1.2 parts anti-settling slurry. Component B comprises 4 parts vinyl silicone oil, 93.45 parts thermally conductive filler, 0.7 parts dispersant, 0.8 parts hydrogen-containing resin, 0.05 parts polymerization inhibitor, and 1.0 part anti-settling slurry. The anti-settling slurry is obtained by dispersing the anti-settling agent in vinyl silicone oil.

[0082] The functional slurry in components A and B is prepared from vinyl silicone oil, dispersant, and antisettling agent in a mass ratio of 1:0.2:1.5. The antisettling agent consists of equal masses of boron nitride whiskers and carbon fibers. The boron nitride whiskers are long whiskers with a length of 200 μm, and the carbon fibers are short-cut carbon fibers with a length of 150 μm. The vinyl silicone oil in components A, B, and the antisettling slurry has a fluorine content of 25 mol% and a viscosity of 60 cp. The vinyl silicone oil is a mixture of double-ended vinyl fluorinated silicone oil and single-ended vinyl fluorinated silicone oil in a mass ratio of 5:2. The dispersant in components A, B, and the antisettling slurry has the structural formula shown in structural formula I, with a number average molecular weight of 4000~5000, and R is Si(OCH2CH3)3.

[0083]

[0084] Structural Formula I The thermally conductive fillers in components A and B are mixtures of alumina, magnesium oxide, and zinc oxide. The total sodium and iron ion content in the thermally conductive fillers is less than 200 ppm, and the pH value is 7 ± 1. The mass ratio of alumina, magnesium oxide, and zinc oxide is 10:3:3. The alumina is spherical with a particle size of 120 μm (sphericity greater than 0.97) and a particle size distribution width of 0.4–0.6. The magnesium oxide is spherical with a particle size of 30 μm and a zinc oxide particle size distribution width of 0.2–0.5. The zinc oxide is near-spherical alumina with a particle size of 0.1 μm and a particle size distribution width of 0.05–0.20.

[0085] The catalyst in component A is a diacetylene bis(triphenylphosphine)platinum complex with a concentration of 9000 ppm, and the colorant is carbon black.

[0086] The molecular formula of the hydrogen-containing resin in component B is (R'SiO). 1.5 )8, where R' is -O((CH2CH2F)CH3SiO) 20 Si(CH3)2H. The polymerization inhibitor is ethynylcyclohexanol.

[0087] The method for preparing the releaseable thermally conductive potting compound in this embodiment includes the following steps: (1) The preparation of anti-settling slurry may include the following steps: placing vinyl silicone oil, dispersant, boron nitride whiskers and carbon fibers in an open container, premixing them with an ultrasonic vibrator for 10 min, with an ultrasonic power of 1500 W and a frequency of 22 KHz; placing them in a 65℃ constant temperature oven for 3 h and then taking them out; pouring them into a high pressure homogenizer for dispersion, setting the pressure to 1000 bar, to obtain anti-settling slurry.

[0088] (2) The preparation steps of component A can be as follows: Add vinyl silicone oil and dispersant to a high-pressure gas flow dispersion vessel by weight, open the gas flow switch valve to introduce dried air at a flow rate of 8 m / s, start the rotation of the central guide shaft at a speed of 8 r / min, disperse for 7 min, then close the gas flow switch valve and stop the rotation of the central guide shaft; Add zinc oxide from the thermally conductive filler to a high-pressure gas flow dispersion vessel by weight, open the gas flow switch valve to introduce dried air at a flow rate of 25 m / s, start the rotation of the central guide shaft at a speed of 15 r / min, disperse for 30 min, then close the gas flow switch valve and stop the rotation of the central guide shaft; Add magnesium oxide from the thermally conductive filler to a high-pressure gas flow dispersion vessel by weight, open the gas flow switch valve to introduce dried air at a flow rate of 8 m / s, start the rotation of the central guide shaft at a speed of 15 r / min, disperse for 30 min, then close the gas flow switch valve and stop the rotation of the central guide shaft; Add aluminum oxide from the thermally conductive filler to a high-pressure gas flow dispersion vessel by weight... In a high-pressure airflow dispersion vessel, open the airflow valve to introduce dried air at a flow rate of 10 m / s, and start the central guide shaft to rotate at a speed of 20 r / min for 90 min. Heat the material to 80℃, hold for 90 min, then close the airflow valve and the central guide shaft to allow the material temperature to return to room temperature. Add the color powder and anti-settling slurry to the high-pressure airflow dispersion vessel by weight, open the airflow valve to introduce dried air at a flow rate of 9 m / s, and start the central guide shaft to rotate at a speed of 20 r / min for 90 min. The guide shaft rotates at a speed of 10 r / min. After dispersion for 40 min, the gas flow switch valve is closed, and the rotation of the central guide shaft is stopped. The catalyst is added to the high-pressure gas flow dispersion vessel by weight. The gas flow switch valve is opened to introduce dried air at a flow rate of 20 m / s. The central guide shaft is started to rotate at a speed of 15 r / min. After dispersion for 10 min, the gas flow switch valve is closed, and the rotation of the central guide shaft is stopped. Vacuum degassing is started for 20 min, and the vacuum degree is less than -0.08 MPa.

[0089] (3) The preparation steps of component B are as follows: Add vinyl silicone oil and dispersant to a high-pressure gas flow dispersion vessel by weight, open the gas flow valve to introduce dried air at a flow rate of 7 m / s, start the central guide shaft to rotate at a speed of 6 r / min, disperse for 8 min, then close the gas flow valve and stop the rotation of the central guide shaft; Add zinc oxide from the thermally conductive filler to a high-pressure gas flow dispersion vessel by weight, open the gas flow valve to introduce dried air at a flow rate of 18 m / s, start the central guide shaft to rotate at a speed of 12 r / min, disperse for 35 min, then close the gas flow valve and stop the rotation of the central guide shaft; Add magnesium oxide from the thermally conductive filler to a high-pressure gas flow dispersion vessel by weight, open the gas flow valve to introduce dried air at a flow rate of 9 m / s, start the central guide shaft to rotate at a speed of 12 r / min, disperse for 35 min, then close the gas flow valve and stop the rotation of the central guide shaft; Add alumina from the thermally conductive filler to a high-pressure gas flow dispersion vessel by weight. In the gas-flow dispersion vessel, open the gas flow valve to introduce dried air at a flow rate of 10 m / s, and start the central guide shaft to rotate at a speed of 15 r / min for 100 min. Heat the material to 70℃, hold for 90 min, then close the gas flow valve and the central guide shaft to allow the material temperature to return to room temperature. Add the hydrogen-containing resin and anti-settling slurry to the high-pressure gas-flow dispersion vessel by weight, open the gas flow valve to introduce dried air at a flow rate of 10 m / s, and start the gas flow dispersion vessel. The central guide shaft rotates at a speed of 10 r / min. After dispersion for 40 min, the gas flow switch valve is closed, and the rotation of the central guide shaft is stopped. The polymerization inhibitor is added to the high-pressure gas flow dispersion vessel by weight. The gas flow switch valve is opened to introduce dried air at a flow rate of 15 m / s. The central guide shaft is started to rotate at a speed of 13 r / min. After dispersion for 13 min, the gas flow switch valve is closed, and the rotation of the central guide shaft is stopped. Vacuum degassing is started for 15 min, and the vacuum degree is less than -0.08 MPa.

[0090] Comparative Example 1 This comparative example is a releaseable thermally conductive potting compound, whose raw materials include component A and component B. Component A includes 8.177 parts of vinyl silicone oil, 91.13 parts of thermally conductive filler, 0.27 parts of dispersant, 0.05 parts of catalyst, 0.02% colorant, and 0.353 parts of boron nitride whiskers (long whiskers with a length of 200 μm). Component B includes 7.177 parts of vinyl silicone oil, 91.193 parts of thermally conductive filler, 0.27 parts of dispersant, 1.0 part of hydrogen-containing resin, 0.007 parts of polymerization inhibitor, and 0.353 parts of boron nitride whiskers (long whiskers with a length of 200 μm).

[0091] The vinyl silicone oil in components A and B has a fluorine content of 5 mol% and a viscosity of 30 cp. The vinyl silicone oil is a mixture of double-ended vinyl fluorinated silicone oil and single-ended vinyl fluorinated silicone oil in a mass ratio of 5:1. The dispersant in components A and B has the structural formula shown in structural formula I, with a number average molecular weight of 4000~5000, and R is Si(OCH3)3.

[0092]

[0093] Structural Formula I The thermally conductive fillers in components A and B are mixtures of alumina, magnesium oxide, and zinc oxide. The total sodium and iron ion content in the thermally conductive fillers is less than 200 ppm, and the pH value is 7 ± 1. The mass ratio of alumina, magnesium oxide, and zinc oxide is 10:2:4. The alumina is spherical with a particle size of 120 μm (sphericity greater than 0.97) and a particle size distribution width of 0.4–0.6. The magnesium oxide is spherical with a particle size of 30 μm and a particle size distribution width of 0.2–0.5. The zinc oxide is near-spherical alumina with a particle size of 0.1 μm and a particle size distribution width of 0.05–0.20.

[0094] The catalyst in component A is a Castrol platinum catalyst with a concentration of 9000 ppm, and the pigment is carbon black.

[0095] The molecular formula of the hydrogen-containing resin in component B is (R'SiO). 1.5 )8, where R' is -O((CH2CH2F)CH3SiO) 20 Si(CH3)2H. The polymerization inhibitor is 3-methyl-1-dodecyn-3-ol.

[0096] The preparation method of the releaseable thermally conductive potting compound in this comparative example is the same as that in Example 1, except that boron nitride whiskers are replaced when adding the anti-settling slurry in Example 1.

[0097] Comparative Example 2 This comparative example is a releaseable thermally conductive potting compound, whose raw materials include component A and component B. Component A includes 5.409 parts of vinyl silicone oil, 93.25 parts of thermally conductive filler, 0.882 parts of dispersant, 0.04 parts of catalyst, 0.01% colorant, and 0.409 parts of carbon fiber (short-cut carbon fiber with a length of 100 μm). Component B includes 4.455 parts of vinyl silicone oil, 93.980 parts of thermally conductive filler, 0.59 parts of dispersant, 0.5 parts of hydrogen-containing resin, 0.020 parts of polymerization inhibitor, and 0.455 parts of carbon fiber (short-cut carbon fiber with a length of 100 μm).

[0098] The vinyl silicone oil in components A and B has a fluorine content of 20 mol% and a viscosity of 100 cp. The vinyl silicone oil is a mixture of double-ended vinyl fluorinated silicone oil and single-ended vinyl fluorinated silicone oil in a mass ratio of 5:3. The dispersant in components A and B has the structural formula shown in Structural Formula I, with a number average molecular weight of 3500-4500, and R represents OH.

[0099]

[0100] Structural Formula I The thermally conductive fillers in components A and B are mixtures of alumina and zinc oxide. The total sodium and iron ion content in the thermally conductive filler impurities is less than 200 ppm, and the pH value is 7 ± 1. The mass ratio of alumina to zinc oxide is 10:2.5. The alumina is spherical with a particle size of 100 μm (sphericity greater than 0.97) and a particle size distribution width of 0.4–0.6. The zinc oxide is near-spherical with a particle size of 2.0 μm and a particle size distribution width of 0.05–0.15.

[0101] The catalyst in component A is a Castells platinum catalyst with a concentration of 5000 ppm, and the colorant is ultramarine blue.

[0102] The molecular formula of the hydrogen-containing resin in component B is (R'SiO). 1.5 )8, where R' is -O((CH2CH2F)CH3SiO) 15 Si(CH3)2H. The polymerization inhibitor is tetramethyltetravinylcyclotetrasiloxane.

[0103] The preparation method of the releaseable thermally conductive potting compound in this comparative example is the same as that in Example 2, except that carbon fiber is replaced when adding the anti-settling slurry in Example 2.

[0104] Comparative Example 3 This comparative example is a releaseable thermally conductive potting compound, whose raw materials include component A and component B. Component A includes 8 parts of vinyl silicone oil, 91.13 parts of thermally conductive filler, 0.2 parts of dispersant, 0.05 parts of catalyst, 0.02% colorant, and 0.6 parts of anti-settling slurry. Component B includes 7 parts of vinyl silicone oil, 91.193 parts of thermally conductive filler, 0.2 parts of dispersant, 1.0 part of hydrogen-containing resin, 0.007 parts of polymerization inhibitor, and 0.6 parts of anti-settling slurry. The anti-settling slurry is obtained by dispersing the anti-settling agent in vinyl silicone oil.

[0105] The functional slurries in components A and B are prepared from vinyl silicone oil, a dispersant, and boron nitride whiskers in a mass ratio of 1:0.4:2.0. The boron nitride whiskers are long and 200 μm in length. The vinyl silicone oil in components A, B, and the anti-settling slurry has a fluorine content of 0 mol% and a viscosity of 30 cp. The vinyl silicone oil is a mixture of double-ended and single-ended vinyl silicone oils in a mass ratio of 5:1. The dispersant in components A, B, and the anti-settling slurry has the structural formula shown in Structural Formula I, with a number average molecular weight of 4000-5000, and R is Si(OCH3)3.

[0106]

[0107] Structural Formula I The thermally conductive fillers in components A and B are mixtures of alumina, magnesium oxide, and zinc oxide. The total sodium and iron ion content in the thermally conductive fillers is less than 200 ppm, and the pH value is 7 ± 1. The mass ratio of alumina, magnesium oxide, and zinc oxide is 10:2:4. The alumina is spherical with a particle size of 120 μm (sphericity greater than 0.97) and a particle size distribution width of 0.4–0.6. The magnesium oxide is spherical with a particle size of 30 μm and a particle size distribution width of 0.2–0.5. The zinc oxide is near-spherical alumina with a particle size of 0.1 μm and a particle size distribution width of 0.05–0.20.

[0108] The catalyst in component A is a Castrol platinum catalyst with a concentration of 9000 ppm, and the pigment is carbon black.

[0109] The molecular formula of the hydrogen-containing resin in component B is (R'SiO). 1.5 )8, where R' is -O((CH2CH2F)CH3SiO) 20 Si(CH3)2H. The polymerization inhibitor is 3-methyl-1-dodecyn-3-ol.

[0110] The preparation method of the releaseable thermally conductive potting compound in this comparative example is the same as that in Example 1.

[0111] Comparative Example 4 This comparative example is a releaseable thermally conductive potting compound, whose raw materials include component A and component B. Component A includes 8 parts of vinyl silicone oil, 91.13 parts of thermally conductive filler, 0.2 parts of dispersant, 0.05 parts of catalyst, 0.02% colorant, and 0.6 parts of anti-settling slurry. Component B includes 7 parts of vinyl silicone oil, 91.193 parts of thermally conductive filler, 0.2 parts of dispersant, 1.0 part of hydrogen-containing resin, 0.007 parts of polymerization inhibitor, and 0.6 parts of anti-settling slurry. The anti-settling slurry is obtained by dispersing the anti-settling agent in vinyl silicone oil.

[0112] The functional slurries in components A and B are prepared from vinyl silicone oil, a dispersant, and boron nitride whiskers in a mass ratio of 1:0.4:2.0. The boron nitride whiskers are long and 200 μm in length. The vinyl silicone oil in components A, B, and the anti-settling slurry has a fluorine content of 5 mol% and a viscosity of 30 cp. The vinyl silicone oil is a mixture of double-ended vinyl fluorinated silicone oil and single-ended vinyl fluorinated silicone oil in a mass ratio of 5:1. The dispersant in components A, B, and the anti-settling slurry has the structural formula shown in Structural Formula I, with a number average molecular weight of 4000~5000, and R is Si(OCH3)3.

[0113]

[0114] Structural Formula I The thermally conductive fillers in components A and B are mixtures of alumina, magnesium oxide, and zinc oxide. The total sodium and iron ion content in the thermally conductive fillers is less than 200 ppm, and the pH value is 7 ± 1. The mass ratio of alumina, magnesium oxide, and zinc oxide is 10:2:4. The alumina is spherical with a particle size of 120 μm (sphericity greater than 0.97) and a particle size distribution width of 0.4–0.6. The magnesium oxide is spherical with a particle size of 30 μm and a particle size distribution width of 0.2–0.5. The zinc oxide is near-spherical alumina with a particle size of 0.1 μm and a particle size distribution width of 0.05–0.20.

[0115] The catalyst in component A is a Castrol platinum catalyst with a concentration of 9000 ppm, and the pigment is carbon black.

[0116] The molecular formula of the hydrogen-containing resin in component B is (R'SiO). 1.5 )8, where R' is -O((CH2CH3)CH3SiO) 20 Si(CH3)2H. The polymerization inhibitor is 3-methyl-1-dodecyn-3-ol.

[0117] The preparation method of the releaseable thermally conductive potting compound in this comparative example is the same as that in Example 1.

[0118] Comparative Example 5 This comparative example is a releaseable thermally conductive potting compound, whose raw materials include component A and component B. Component A includes 8 parts of vinyl silicone oil, 91.13 parts of thermally conductive filler, 0.2 parts of dispersant, 0.05 parts of catalyst, 0.02% colorant, and 0.6 parts of anti-settling slurry. Component B includes 7 parts of vinyl silicone oil, 91.193 parts of thermally conductive filler, 0.2 parts of dispersant, 1.0 part of hydrogen-containing resin, 0.007 parts of polymerization inhibitor, and 0.6 parts of anti-settling slurry. The anti-settling slurry is obtained by dispersing the anti-settling agent in vinyl silicone oil.

[0119] The functional slurries in components A and B are prepared from vinyl silicone oil, a dispersant, and boron nitride whiskers in a mass ratio of 1:0.4:2.0. The boron nitride whiskers are long and 200 μm in length. The vinyl silicone oil in components A, B, and the anti-settling slurry has a fluorine content of 0 mol% and a viscosity of 30 cp. The vinyl silicone oil is a mixture of double-ended and single-ended vinyl silicone oils in a mass ratio of 5:1. The dispersant in components A, B, and the anti-settling slurry has the structural formula shown in Structural Formula I, with a number average molecular weight of 4000-5000, and R is Si(OCH3)3.

[0120]

[0121] Structural Formula I The thermally conductive fillers in components A and B are mixtures of alumina, magnesium oxide, and zinc oxide. The total sodium and iron ion content in the thermally conductive fillers is less than 200 ppm, and the pH value is 7 ± 1. The mass ratio of alumina, magnesium oxide, and zinc oxide is 10:2:4. The alumina is spherical with a particle size of 120 μm (sphericity greater than 0.97) and a particle size distribution width of 0.4–0.6. The magnesium oxide is spherical with a particle size of 30 μm and a particle size distribution width of 0.2–0.5. The zinc oxide is near-spherical alumina with a particle size of 0.1 μm and a particle size distribution width of 0.05–0.20.

[0122] The catalyst in component A is a Castrol platinum catalyst with a concentration of 9000 ppm, and the pigment is carbon black.

[0123] The molecular formula of the hydrogen-containing resin in component B is (R'SiO). 1.5 )8, where R' is -O((CH2CH3)CH3SiO) 20 Si(CH3)2H. The polymerization inhibitor is 3-methyl-1-dodecyn-3-ol.

[0124] The preparation method of the releaseable thermally conductive potting compound in this comparative example is the same as that in Example 1.

[0125] Comparative Example 6 The difference between Comparative Example 6 and Example 1 is that the filler used is different, but everything else is the same.

[0126] The thermally conductive fillers in components A and B are mixtures of alumina, magnesium oxide, and zinc oxide. The total sodium and iron ion content in the thermally conductive fillers is less than 200 ppm, and the pH value is 7 ± 1. The mass ratio of alumina, magnesium oxide, and zinc oxide is 10:2:4. The alumina consists of spherical alumina with a particle size of 120 μm (sphericity 0.92) and a particle size distribution width of 0.8. The magnesium oxide consists of spherical zinc oxide with a particle size of 30 μm (sphericity 0.86) and a particle size distribution width of 0.7. The zinc oxide consists of near-spherical alumina with a particle size of 0.1 μm and a particle size distribution width of 0.6.

[0127] The components A and B of Examples 1-3 and Comparative Examples 1-6 were mixed at a mass ratio of 1:1 and cured at 80°C for 30 minutes. The performance was then tested. The performance test conditions are as follows, and the test results are shown in Table 1.

[0128] Thermal conductivity was tested using ASTM D5470, "Standard Test Method for Thermal Transfer Properties of Thermally Conductive and Electrically Insulating Materials (Chinese Version)". Tear strength was tested using GB / T 529-2008, "Determination of Tear Strength of Vulcanized Rubber or Thermoplastic Rubber". For mold release, the potting compound was mixed and poured into a PC test mold, transferred to an 80℃ oven for 20 minutes to cure, removed, cooled to room temperature, and the potting compound was removed from the mold. The percentage of residual adhesive area on the mold was recorded. The viscosity of components A and B immediately after mixing was also measured. For sedimentation, 1 kg of the unmixed potting compound was placed in an open container, fixed on a shaking platform, and the frequency was set to 120 cycles / min. The time it took for the potting compound to settle was observed and recorded.

[0129] Table 1 Performance test results of potting compounds in Examples 1-3 and Comparative Examples 1-6

[0130] As shown in Table 1, the potting compounds in Examples 1-3 use specific vinyl silicone oil, specific hydrogen-containing resin, and thermally conductive fillers with specific particle sizes. Boron nitride whiskers or carbon fibers are added to the potting compound to significantly enhance its strength and release properties. The thermal conductivity can reach over 6.0 W / mk, and the viscosity is low. It takes a long time for sedimentation to occur after accelerated vibration. Therefore, it can be applied to power electronic working modules by injection molding.

[0131] Although Comparative Examples 1 and 2 also contain boron nitride whiskers or carbon fibers, which are beneficial for improving thermal conductivity, their direct addition to the potting compound makes it difficult to deagglomerate and disperse the agglomerates of boron nitride whiskers or carbon fibers due to the barrier effect of other thermally conductive fillers, which constitute the majority of the composition. Furthermore, the dispersant originally present in the slurry, when added directly to the potting compound, will be diluted by other components, resulting in poor dispersion.

[0132] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, it is not limited to those listed in the embodiments. Those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A releaseable thermally conductive potting compound, characterized in that, The raw materials, by weight, include component A and component B. Component A includes 4-8 parts of vinyl silicone oil, 85-96 parts of thermally conductive filler, 0.2-0.8 parts of dispersant, 0.03-0.05 parts of catalyst, and 0.6-1.3 parts of anti-settling slurry. Component B includes 3-7 parts of the vinyl silicone oil, 85-96 parts of the thermally conductive filler, 0.2-0.8 parts of dispersant, 0.1-1.0 parts of hydrogen-containing resin, and 0.007-0. The mixture comprises 0.60 parts of a polymerization inhibitor and 0.6-1.3 parts of the anti-settling slurry; the thermally conductive filler is at least one selected from alumina, magnesium oxide, and zinc oxide, and the particle size distribution width of the thermally conductive filler is ≤0.6; the anti-settling slurry is obtained by dispersing an anti-settling agent in the vinyl silicone oil; the anti-settling agent is selected from boron nitride whiskers and / or carbon fibers; the vinyl silicone oil is a mixture of double-ended vinyl fluorinated silicone oil and single-ended vinyl fluorinated silicone oil; and the molecular formula of the hydrogen-containing resin is (R'SiO). 1.5 )8, where R' is -O((CH2CH2F)CH3SiO) n Si(CH3)2H, where n is any natural number from 1 to 20.

2. The releaseable thermally conductive potting compound according to claim 1, characterized in that, Includes at least one of the following features (1) to (8): (1) The fluorine content of the vinyl silicone oil is 5~30 mol%, and the viscosity is 30~150 cp; (2) The mass ratio of the double-ended vinyl fluorinated silicone oil to the single-ended vinyl fluorinated silicone oil is 5:1~3; (3) The thermally conductive filler includes a first filler, a second filler and a third filler. The first filler, the second filler and the third filler have different particle size parameters. The first filler is spherical or near-spherical, and the sphericity of the spherical shape is greater than 0.

97. The particle size of the first filler is 60~120μm and the particle size distribution width of the first filler is 0.4~0.

6. The second filler is spherical, and the sphericity of the spherical shape is greater than 0.

95. The particle size of the second filler is 5~30μm and the particle size distribution width of the second filler is 0.2~0.

5. The third filler is spherical or angular, and the sphericity of the spherical shape is greater than 0.

94. The particle size of the third filler is 0.1~3.0μm and the particle size distribution width of the third filler is 0.05~0.

20. (4) The thermally conductive filler is a mixture of alumina, magnesium oxide and zinc oxide, and the mass ratio of alumina, magnesium oxide and zinc oxide is 10:2~6:0.5~4.0; (5) The total content of sodium and iron ions in the thermally conductive filler is less than 200 ppm, and the pH value in the aqueous solution is 7±1; (6) The number-average molecular weight of the dispersant is 2000~6000, and the structural formula of the dispersant is shown in structural formula I, wherein R is Si(OCH3)3, Si(OCH2CH3)3 or OH. Structural Formula I; (7) The catalyst is a Castells platinum catalyst with a concentration of 500~9000 ppm; (8) The polymerization inhibitor is selected from at least one of 3-methyl-1-dodecyn-3-ol, methylbutynol, ethynylcyclohexanol, tetramethyldivinyldisiloxane and tetramethyltetravinylcyclotetrasiloxane.

3. The releaseable thermally conductive potting compound according to claim 1, characterized in that, The functional slurry contains a dispersant, and the mass ratio of the vinyl silicone oil, the dispersant, and the anti-settling agent is 1:0.1~0.4:0.5~2.

0.

4. The releaseable thermally conductive potting compound according to claim 3, characterized in that, The dispersant has a number-average molecular weight of 2000-6000, and its structural formula is shown in structural formula I, wherein R is Si(OCH3)3, Si(OCH2CH3)3, or OH. Structural formula I.

5. The releaseable thermally conductive potting compound according to claim 1, characterized in that, The boron nitride whiskers are long and whisker-shaped with a length of 30~200μm.

6. The releaseable thermally conductive potting compound according to claim 1, characterized in that, The carbon fiber is short-cut carbon fiber with a length of 50~200μm.

7. The releaseable thermally conductive potting compound according to claim 1, characterized in that, Component A further includes 0.01 to 0.02 parts of color powder, wherein the color powder is selected from any one of carbon black, iron oxide red, iron oxide yellow, ultramarine blue and phthalocyanine blue.

8. A method for preparing a releaseable thermally conductive potting compound according to any one of claims 1 to 7, characterized in that, Including the following steps: ①Preparation of component A After mixing the vinyl silicone oil and the dispersant in a high-pressure gas flow dispersion vessel, dry air is introduced and each thermally conductive filler in the thermally conductive filler is added step by step. The temperature is raised and kept at a certain temperature for a certain time, then cooled to room temperature and the anti-settling slurry is added. After adding the catalyst and mixing, vacuum defoaming is performed. ②Preparation of component B After mixing the vinyl silicone oil and the dispersant in a high-pressure gas flow dispersion vessel, dry air is introduced and each thermally conductive filler in the thermally conductive filler is added step by step. The temperature is raised and held for a certain time, then cooled to room temperature and the hydrogen-containing resin and the anti-settling slurry are added. After adding the polymerization inhibitor and mixing, vacuum defoaming is performed.

9. The preparation method according to claim 8, characterized in that, The preparation of the anti-settling slurry includes the following steps: treating the vinyl silicone oil, the anti-settling agent, and the dispersant with ultrasonic vibration according to the formula amount, heating and maintaining a constant temperature for a certain period of time, and then dispersing them using a high-pressure homogenizer.

10. The application of the releaseable thermally conductive potting compound according to any one of claims 1 to 7 in a power electronic working module, characterized in that, The power electronic working module includes a thermal interface material and a chip, and the demoldable thermally conductive potting compound is injected and potted into the power electronic working module.

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