Two-component high-thermal-conductivity gel and preparation method thereof

Abstract

The invention discloses a two-component high-thermal-conductivity gel and a preparation method thereof, and belongs to the technical field of thermal interface materials, and the key point of the technical scheme is that the two-component high-thermal-conductivity gel comprises a component A and a component B, the component A is prepared from the following raw materials in parts by mass: 90 to 110 parts of phenyl vinyl siloxane, 2 to 4 parts of fluorinated silicon oil, 4.5 to 6 parts of hydrogen-containing silicone oil, 1700 to 1900 parts of heat-conducting filler, 8 to 12 parts of surfactant and 0.1 to 0.3 part of inhibitor; the component B is prepared from the following raw materials in parts by mass: 90 to 110 parts of phenyl vinyl siloxane, 2 to 4 parts of silicon fluoride oil, 1700 to 1900 parts of heat-conducting filler, 8 to 12 parts of surfactant and 1 to 3 parts of catalyst. According to the invention, through crosslinking density control and design of the interface controllable stripping layer, good balance between heat-conducting property and easy stripping property is realized, and the application reliability and the service life of the gel are obviously improved and prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal interface materials, and in particular to a two-component high thermal conductivity gel and a preparation method thereof. Background Art

[0002] With the widespread use and miniaturization of electronic devices, electronic integrated circuits and components generate significant heat during use, seriously impacting their operational stability and service life. To improve the heat dissipation performance of electronic devices, thermal interface materials are widely used as coatings between heat dissipating and heating components to reduce the contact thermal resistance between them. Currently, thermally conductive gels, a common thermal interface material, are widely adopted due to their excellent thermal conductivity and ease of use.

[0003] However, existing thermally conductive gels still have some problems. First, the thermal conductivity of most thermally conductive gels is low, which makes it difficult to meet the needs of actual applications. Second, during long-term use, thermally conductive gels are prone to drying out and powdering, resulting in unstable performance or even damage to electronic components. In addition, when the application scenario of thermally conductive gels requires vertical placement, such as in security cameras, they are prone to position changes and cracking, resulting in a sharp increase in thermal resistance between interfaces and deterioration of the heat dissipation effect.

[0004] To solve these problems, researchers have been exploring new thermal interface materials. Filling silicone materials with inorganic thermally conductive fillers is an effective way to improve thermal conductivity. However, how to achieve easy-to-peel interface properties while maintaining high thermal conductivity has become the focus and difficulty of current research. This is also of great significance for improving the service life and reliability of thermally conductive gels, especially in scenarios that require repeated bonding or use in dynamic environments. Therefore, the development of a new thermally conductive gel with both high thermal conductivity and easy peelability has important research value and application prospects. Summary of the Invention

[0005] In order to solve the problems in the prior art, the present invention provides a two-component high thermal conductivity gel and a preparation method thereof. The present invention achieves a good balance between thermal conductivity and easy peelability by controlling the cross-linking density and designing a controllable interface peeling layer, thereby significantly improving the application reliability and service life of the gel.

[0006] The first aspect of the present invention is to provide a two-component high thermal conductivity gel, which adopts the following technical solution: A two-component high thermal conductivity gel comprises a component A and a component B. Component A comprises the following raw materials in parts by mass: 90-110 parts of phenyl vinyl siloxane, 2-4 parts of fluorinated silicone oil, 4.5-6 parts of hydrogenated silicone oil, 1700-1900 parts of thermally conductive filler, 8-12 parts of surfactant, and 0.1-0.3 parts of inhibitor; and component B comprises the following raw materials in parts by mass: 90-110 parts of phenyl vinyl siloxane, 2-4 parts of fluorinated silicone oil, 1700-1900 parts of thermally conductive filler, 8-12 parts of surfactant, and 1-3 parts of catalyst.

[0007] As an example, the content of fluorinated silicone oil can be 2 parts, 3 parts, 4 parts or a range of any two numbers; the content of thermal conductive filler can be 1700 parts, 1750 parts, 1800 parts, 1850 parts, 1900 parts or a range of any two numbers; the content of surfactant can be 8 parts, 9 parts, 10 parts, 11 parts, 12 parts or a range of any two numbers.

[0008] As an example, the hydrogen-containing silicone oil may be 2 parts, 3 parts, 4 parts, or a range of any two numbers.

[0009] In the present application, phenyl vinyl siloxane has a chain structure and does not include phenyl vinyl siloxane with a ring structure.

[0010] Preferably, the phenyl content in the phenyl vinyl siloxane is 5-20%, and the vinyl content is 0.4-1.0%. In this application, the phenyl vinyl siloxane can be a commercial product or a homemade product, as long as the phenyl content and vinyl content are within the range disclosed in this application.

[0011] The phenyl content is used to adjust the flexibility of the product after gel vulcanization, and the ethyl content is used to ensure cross-linking activity and avoid the vulcanized product being too brittle or too sticky.

[0012] As an example, the phenyl content can be 5%, 7%, 10%, 12%, 15%, 18%, 20% or a range of any two numbers, and the vinyl content can be 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0% or a range of any two numbers. When the phenyl content is higher than 20%, the steric hindrance and rigidity of the phenyl group hinder the segment movement of the phenyl vinyl silane, and the strength and hardness of the thermal conductive gel will be significantly increased, and the flexibility will be greatly reduced. When the phenyl content is lower than 5%, the intermolecular force is weakened, resulting in a significant decrease in tensile strength; when the vinyl content is lower than 0.4%, the cross-linking density between the phenyl vinyl siloxane and the hydrogenated silicone oil is insufficient, resulting in the gel being sticky and the strength being reduced. When the vinyl content is higher than 1.0%, the cross-linking network is too dense, making the gel brittle and the flexibility dropping sharply.

[0013] Preferably, the phenyl vinyl siloxane is prepared from raw materials phenyl siloxane, methyl siloxane and vinyl siloxane.

[0014] Phenyl siloxane can be selected from diphenyldimethoxysilane, diphenyldiethoxysilane, octaphenylcyclotetrasiloxane, phenyltrimethoxysilane, phenyltriethoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, hexaphenylcyclotrisiloxane, tetraphenylcyclotetrasiloxane, triphenyltrimethylcyclotrisiloxane, diphenyltetramethylcyclotrisiloxane, pentaphenylmethylcyclotrisiloxane, phenylpentamethylcyclotrisiloxane, tetraphenyldimethylcyclotrisiloxane, phenylheptamethylcyclotetrasiloxane, etc. The methylsiloxane may be dimethyldimethoxysilane, dimethyldiethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, dimethylsiloxane linear oligomer, hydroxyl-terminated polydimethylsiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, trimethyltriethylcyclotrisiloxane, tetramethyltetraethylcyclotetrasiloxane, pentamethyltriphenylcyclotetrasiloxane, dimethylhexaethylcyclotetrasiloxane, etc.; Vinyl siloxanes may include vinyltrimethoxysilane, vinyltriethoxysilane, divinyldimethoxysilane, divinyldiethoxysilane, methylvinyldimethoxysilane, methylvinyldiethoxysilane, tetramethyltetravinylcyclotetrasiloxane, vinyl-terminated polydimethylsiloxane, trimethyltrivinylcyclotrisiloxane, dimethyldivinylcyclotrisiloxane, methylpentavinylcyclotrisiloxane, phenylmethylvinylcyclotrisiloxane, etc. Preferably, the phenyl vinyl siloxane is prepared by hydrolysis and polycondensation reaction of raw materials phenyl siloxane, methyl siloxane and vinyl siloxane in a molar ratio of (5-20): (79-94.6): (0.4-1.0); Preferably, the reaction temperature is 100-120°C and the reaction time is 3-5h; Preferably, the reaction catalyst is a basic catalyst; Preferably, the reaction is terminated when the viscosity of the reaction solution is monitored to be 500-1000 mPa·s (25° C.).

[0015] As an example, the molar ratio of phenylsiloxane, methylsiloxane and vinylsiloxane can be 5:79:0.4, 5:85:0.8, 5:94.6:0.4, 5:94.6:1, 10:89:0.4, 10:96.4:1, 15:84.6:0.4, 15:94.6:1, 20:82:0.4, 20:79:1, 20:96.4:1 or a range of any two numbers therein. Phenylsiloxane increases the rigidity of the gel, and the flexibility and reactivity of the methylsiloxane leading chain are controlled. Vinyl silicone is a key factor in rigidity and flexibility. The introduction of cross-linkable double bonds in vinyl silicone requires precise dosage to avoid gelation. Therefore, when the content of phenyl silicone is too low, the gel is too soft, and when it is too high, the gel is too hard and brittle. When the content of vinyl silicone is lower than the lower limit, it will lead to insufficient curing with hydrogenated silicone oil and overall deterioration of performance. When it is higher than the upper limit, it will easily lead to excessive cross-linking and brittleness of the gel. When the content of methyl silicone is too high, the phenyl vinyl silicone will be too soft and have low viscosity, which will lead to the gel being too soft and having poor strength. When the content is too low, the viscosity of phenyl vinyl silicone will be high, which will make the gel processing difficult and the gel too hard, too brittle and easy to crack after curing.

[0016] Preferably, the hydrogen content in the hydrogen-containing silicone oil is 0.1-0.8%.

[0017] As an example, the hydrogen content can be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8% or a range of any two numbers therein. When the hydrogen content in the hydrogen-containing silicone oil is lower than 0.1%, the reaction of phenyl vinyl siloxane with the hydrogen-containing silicone oil is incomplete, resulting in some vinyl groups being unable to participate in the reaction, thereby forming a loose network structure, low gel strength, and prone to permanent deformation. In addition, due to insufficient supporting force of the cross-linked network, the thermal conductive filler is easily caused to settle, thereby destroying the thermal conduction path. When the hydrogen content is higher than 0.8%, excessive Si-H groups react with vinyl groups to form a rigid network, which hinders the movement of chain segments, reduces flexibility, increases brittleness, and is prone to thermal stress cracking.

[0018] Preferably, the molecular weight of the fluorinated silicone oil is 20-30KDa; And / or, the surfactant is a silane coupling agent; And / or, the catalyst is at least one of a platinum catalyst, a rhodium catalyst and a palladium catalyst; And / or, the inhibitor is at least one of alkynyl cyclohexanol and alkynol compounds.

[0019] Preferably, the thermally conductive filler comprises aluminum nitride powder and aluminum oxide powder in a weight ratio of (1.9-2.1):1.

[0020] Preferably, the particle size of the aluminum nitride powder is 10-90 μm; Preferably, the particle size of the aluminum nitride powder is at least 10-20 μm and 70-90 μm; Preferably, the weight ratio of the aluminum nitride powder with a particle size of 70-90 μm to the aluminum nitride powder with a particle size of 10-20 μm is (8-10):11.

[0021] Preferably, the particle size of the alumina powder is 0.5-10 μm; Preferably, the particle size of the alumina powder includes at least 0.5-1.5 μm and 4-10 μm; Preferably, the weight ratio of the aluminum oxide powder with a particle size of 4-10 μm to the aluminum oxide powder with a particle size of 0.5-1.5 μm is (1-2):1.

[0022] As an example, the weight ratio of aluminum nitride powder to alumina powder can be 1.9:1, 2.0:1, 2.1:1 or a range of any two numbers, the particle size of large-particle powder in aluminum nitride powder is 70μm, 75μm, 80μm, 85μm, 90μm or a range of any two numbers, and the particle size of small-particle powder in aluminum nitride powder is 10μm, 12μm, 15μm, 18μm, 20μm or a range of any two numbers; alumina powder is used as a small-particle material for filling gaps, and aluminum nitride powder is a large-particle material for the skeleton. When the ratio and particle size of aluminum nitride powder and alumina powder are within the above range, it can effectively ensure the formation of a heat conduction path inside the gel, thereby improving the thermal conductivity of the gel.

[0023] By adopting the above technical solution, phenyl vinyl siloxane is used as the base material, which reacts with hydrogenated silicone oil to form a three-dimensional cross-linked network, thereby improving the mechanical strength and aging resistance of the two-component thermally conductive gel after curing, and effectively solving the problems of drying and powdering of the thermally conductive gel during long-term use. At the same time, when aluminum nitride and aluminum oxide of two particle sizes are selected as thermally conductive fillers, aluminum nitride provides a rigid skeleton for the thermally conductive gel, and aluminum oxide is used to reduce friction between the thermally conductive fillers and fill gaps. After the thermally conductive filler is modified with a surfactant, the dispersion performance of the thermally conductive filler in the base material is improved, and the agglomeration of the thermally conductive filler is avoided. As a result, the cross-linked thermally conductive gel forms a dense network structure, realizes the formation of an effective thermally conductive network, ensures that heat is efficiently transferred through the thermally conductive filler, and makes the thermal conductivity coefficient of the two-component thermally conductive gel between 6.0-6.5w / m·K.

[0024] The addition of fluorinated silicone oil migrates to the surface of the gel during the curing process of components A and B, forming a controllable peeling layer, which significantly reduces the interfacial adhesion and makes the two-component thermal conductive gel easy to peel after curing. The 180° peeling force is ≤0.4N / 25mm. At the same time, it maintains good interfacial bonding strength, effectively solving problems such as position change and cracking when placed vertically. After the fluorinated silicone oil is enriched on the gel surface, it also improves the water resistance and solvent resistance of the gel, thereby forming a stable interfacial protective layer.

[0025] In summary, the two-component thermally conductive gel obtained in the present invention can be widely used in the fields of electronic device heat dissipation, medical hot compresses, flexible display modules, etc., and is particularly suitable for scenarios that require repeated lamination or use in dynamic environments.

[0026] The second aspect of the present invention is to provide a method for preparing the two-component high thermal conductivity gel as described above, comprising the following steps: S1. preparing a base material by using phenyl vinyl siloxane and fluorinated silicone oil in proportion; S2. Modifying the thermally conductive filler with a surfactant to obtain a modified thermally conductive filler; S3, adding the modified thermal conductive filler and inhibitor in the formula amount to the base material, and then adding hydrogen-containing silicone oil and mixing evenly to prepare component A of the two-component thermal conductive gel; S4. Add the modified thermal conductive filler and catalyst in the formula amount to the base material, mix them evenly, and prepare component B of the two-component thermal conductive gel.

[0027] Preferably, the reaction temperature in step S1 is 155-165° C., and the reaction time is 55-60 min at a constant temperature under vacuum. In summary, the present invention has the following beneficial effects: 1. The present invention significantly improves the thermal conductivity of the thermal conductive gel by adding aluminum nitride and aluminum oxide and setting the particle size of aluminum nitride and aluminum oxide, thereby meeting the requirements of electronic devices for high thermal conductivity and effectively improving the heat dissipation effect.

[0028] 2. Phenyl vinyl siloxane is used as the matrix material, which reacts with hydrogenated silicone oil to form a dense three-dimensional network structure, thereby improving the mechanical strength and aging resistance of the two-component thermal conductive gel after curing, and effectively solving the problems of drying and powdering of the gel during long-term use.

[0029] 3. The addition of fluorinated silicone oil can form a controllable peeling layer rich in fluorinated silicone oil on the surface of the thermal conductive gel, which significantly reduces the interfacial adhesion and makes the two-component thermal conductive gel easy to peel off after curing. At the same time, it maintains good interfacial bonding strength, effectively solving problems such as position change and cracking when placed vertically. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below with reference to the examples. All reagents without manufacturer's indication are conventional reagents that can be purchased commercially.

[0031] The reaction amount, reaction temperature, reaction time, catalyst, etc. for preparing phenyl vinyl siloxane using different phenyl siloxanes, methyl siloxanes, and vinyl siloxanes may be slightly different. In this application, octaphenylcyclotetrasiloxane, octamethylcyclotetrasiloxane, and tetramethyltetravinylcyclotetrasiloxane are used as examples, as follows: Preparation Example 1 A method for preparing phenyl vinyl siloxane comprises the following steps: Phenylsiloxane, methylsiloxane, and vinylsiloxane were mixed in a molar ratio of 20:79.6:0.4, 0.05 wt% (total mass percentage) of potassium hydroxide catalyst was added, and the mixture was reacted at 120° C. for 5 h. The viscosity was monitored to be 900 mPa·s (25° C.). Acetic acid was added to quench the reaction, and low-boiling-point substances were removed by distillation under reduced pressure to obtain phenylvinylsiloxane having a phenyl content of 20% and a vinyl content of 0.4%. In this preparation example, octaphenylcyclotetrasiloxane is used as phenylsiloxane; octamethylcyclotetrasiloxane is used as methylsiloxane; The vinyl siloxane used is tetramethyltetravinylcyclotetrasiloxane.

[0032] Preparation Example 2 A method for preparing phenyl vinyl siloxane comprises the following steps: Phenylsiloxane, methylsiloxane, and vinylsiloxane were mixed in a molar ratio of 20:79:1, 0.05 wt% (total mass percentage) of potassium hydroxide catalyst was added, and the mixture was reacted at 120° C. for 5 h. The viscosity was monitored to be 900 mPa·s (25° C.). Acetic acid was added to quench the reaction, and low-boiling substances were removed by distillation under reduced pressure to obtain phenylvinylsiloxane with a phenyl content of 20% and a vinyl content of 1%. The phenylsiloxane is octaphenylcyclotetrasiloxane; The methylsiloxane uses octamethylcyclotetrasiloxane; The vinyl siloxane used is tetramethyltetravinylcyclotetrasiloxane.

[0033] Preparation Example 3 A method for preparing phenyl vinyl siloxane comprises the following steps: Phenylsiloxane, methylsiloxane, and vinylsiloxane were mixed in a molar ratio of 15:84.6:0.4, 0.05 wt% (total mass percentage) of potassium hydroxide catalyst was added, and the mixture was reacted at 110° C. for 4 h. The viscosity was monitored to be 700 mPa·s (25° C.). Acetic acid was added to quench the reaction, and low-boiling-point substances were removed by distillation under reduced pressure to obtain phenylvinylsiloxane having a phenyl content of 15% and a vinyl content of 0.4%. The phenylsiloxane is octaphenylcyclotetrasiloxane; The methylsiloxane uses octamethylcyclotetrasiloxane; The vinyl siloxane used is tetramethyltetravinylcyclotetrasiloxane.

[0034] Preparation Example 4 A method for preparing phenyl vinyl siloxane comprises the following steps: Phenylsiloxane, methylsiloxane, and vinylsiloxane were mixed in a molar ratio of 15:84:1, 0.05 wt% (total mass percentage) of potassium hydroxide catalyst was added, and the mixture was reacted at 110° C. for 4 h. The viscosity was monitored to be 700 mPa·s (25° C.). Acetic acid was added to quench the reaction, and low-boiling substances were removed by distillation under reduced pressure to obtain phenylvinylsiloxane with a phenyl content of 15% and a vinyl content of 1%. The phenylsiloxane is octaphenylcyclotetrasiloxane; The methylsiloxane uses octamethylcyclotetrasiloxane; The vinyl siloxane used is tetramethyltetravinylcyclotetrasiloxane.

[0035] Preparation Example 5 A method for preparing phenyl vinyl siloxane comprises the following steps: Phenylsiloxane, methylsiloxane, and vinylsiloxane were mixed in a molar ratio of 10:89.6:0.4, 0.05 wt% (total mass percentage) of potassium hydroxide catalyst was added, and the mixture was reacted at 100° C. for 4 h. The viscosity was monitored to be 600 mPa·s (25° C.). Acetic acid was added to quench the reaction, and low-boiling-point substances were removed by distillation under reduced pressure to obtain phenylvinylsiloxane having a phenyl content of 10% and a vinyl content of 0.4%. The phenylsiloxane is octaphenylcyclotetrasiloxane; The methylsiloxane uses octamethylcyclotetrasiloxane; The vinyl siloxane used is tetramethyltetravinylcyclotetrasiloxane.

[0036] Preparation Example 6 A method for preparing phenyl vinyl siloxane comprises the following steps: Phenylsiloxane, methylsiloxane, and vinylsiloxane were mixed in a molar ratio of 10:89:1, 0.05 wt% (total mass percentage) of potassium hydroxide catalyst was added, and the mixture was reacted at 100° C. for 4 h. The viscosity was monitored to be 600 mPa·s (25° C.). Acetic acid was added to quench the reaction, and low-boiling substances were removed by vacuum distillation to obtain phenylvinylsiloxane with a phenyl content of 10% and a vinyl content of 1%. The phenylsiloxane is octaphenylcyclotetrasiloxane; The methylsiloxane uses octamethylcyclotetrasiloxane; The vinyl siloxane used is tetramethyltetravinylcyclotetrasiloxane.

[0037] Preparation Example 7 A method for preparing phenyl vinyl siloxane comprises the following steps: Phenylsiloxane, methylsiloxane, and vinylsiloxane were mixed in a molar ratio of 5:94.6:0.4, 0.05 wt% (total mass percentage) of potassium hydroxide catalyst was added, and the mixture was reacted at 100° C. for 3 h. The viscosity was monitored to be 500 mPa·s (25° C.). Acetic acid was added to quench the reaction, and low-boiling substances were removed by distillation under reduced pressure to obtain phenylvinylsiloxane with a phenyl content of 5% and a vinyl content of 0.4%. The phenylsiloxane is octaphenylcyclotetrasiloxane; The methylsiloxane uses octamethylcyclotetrasiloxane; The vinyl siloxane used is tetramethyltetravinylcyclotetrasiloxane.

[0038] Preparation Example 8 A method for preparing phenyl vinyl siloxane comprises the following steps: Phenylsiloxane, methylsiloxane, and vinylsiloxane were mixed in a molar ratio of 5:94:1, 0.05 wt% (total mass percentage) of potassium hydroxide catalyst was added, and the mixture was reacted at 100° C. for 3 h. The viscosity was monitored to be 500 mPa·s (25° C.). Acetic acid was added to quench the reaction, and low-boiling substances were removed by vacuum distillation to obtain phenylvinylsiloxane with a phenyl content of 5% and a vinyl content of 1%. The phenylsiloxane is octaphenylcyclotetrasiloxane; The methylsiloxane uses octamethylcyclotetrasiloxane; The vinyl siloxane used is tetramethyltetravinylcyclotetrasiloxane.

[0039] Example 1 A method for preparing a two-component high thermal conductivity gel comprises the following steps: S1. Prepare two base materials as follows: 9 kg of phenyl vinyl siloxane obtained in Preparation Example 1 and 0.2 kg of fluorinated silicone oil (molecular weight 20-30 kDa) were stirred and mixed at room temperature for 5 min, then heated to 55° C. and stirred for 5 min. The mixture was then kept in a vacuum at 155° C. for 55 min, and then cooled to room temperature to obtain base materials A and B, respectively. S2. Prepare two modified thermally conductive fillers by the following method: dissolve 0.8 kg of KH-550 in 150 kg of a 60 wt% ethanol aqueous solution, then add 170 kg of the thermally conductive filler, react at 60° C. for 2 h, filter, wash, and dry to obtain two modified thermally conductive fillers; The thermal conductive filler includes aluminum nitride powder and aluminum oxide powder in a weight ratio of 1.9:1. The aluminum nitride powder is composed of two powders with particle sizes of 70μm and 10μm in a weight ratio of 9:11. The aluminum oxide powder is composed of two powders with particle sizes of 4μm and 0.5μm in a weight ratio of 1.5:1. S3. Add one portion of modified thermally conductive filler and 0.01 kg of inhibitor ethynyl cyclyl alcohol to matrix material A, then add 0.45 kg of hydrogenated silicone oil (hydrogen content 0.25%), stir under vacuum for 5 minutes, and release the vacuum to obtain component A of the two-component thermally conductive gel; S4. Add another portion of the modified thermal conductive filler and 0.1 kg of platinum catalyst to the B matrix material, stir for 5 minutes under vacuum conditions, and release the vacuum to obtain the B component of the two-component thermal conductive gel.

[0040] Example 2 A method for preparing a two-component high thermal conductivity gel comprises the following steps: S1. Prepare two base materials as follows: 10 kg of the phenyl vinyl siloxane obtained in Preparation Example 1 and 0.3 kg of fluorinated silicone oil (molecular weight 20-30 kDa) were stirred and mixed at room temperature for 10 min, then heated to 60° C. and stirred for 10 min. The mixture was then kept in a vacuum at 160° C. for 60 min, and then cooled to room temperature to obtain base materials A and B, respectively. S2. Prepare two modified thermally conductive fillers by the following method: dissolve 1.0 kg of KH-550 in 150 kg of a 60 wt% ethanol aqueous solution, then add 180 kg of the thermally conductive filler, react at 60° C. for 2 h, filter, wash, and dry to obtain two modified thermally conductive fillers; The thermal conductive filler includes aluminum nitride powder and aluminum oxide powder in a weight ratio of 2:1. The aluminum nitride powder is composed of two powders with particle sizes of 90μm and 20μm in a weight ratio of 9:11. The aluminum oxide powder is composed of two powders with particle sizes of 7μm and 1μm in a weight ratio of 1.5:1. S3. Add one portion of modified thermally conductive filler and 0.02 kg of inhibitor ethynyl cyclyl alcohol to matrix material A, then add 0.45 kg of hydrogenated silicone oil (hydrogen content 0.25%), stir under vacuum for 10 minutes, and release the vacuum to obtain component A of the two-component thermally conductive gel; S4. Add another portion of the modified thermal conductive filler and 0.2 kg of platinum catalyst to the B matrix material, stir under vacuum conditions for 10 minutes, and release the vacuum to obtain the B component of the two-component thermal conductive gel.

[0041] Example 3 A method for preparing a two-component high thermal conductivity gel comprises the following steps: S1. Prepare two base materials as follows: 11 kg of the phenyl vinyl siloxane obtained in Preparation Example 1 and 0.4 kg of fluorinated silicone oil (molecular weight 20-30 kDa) were stirred and mixed at room temperature for 10 min, then heated to 65° C. and stirred for 10 min. The mixture was then kept in a vacuum at 165° C. for 60 min, and then cooled to room temperature to obtain base materials A and B, respectively. S2. Prepare two modified thermally conductive fillers by the following method: dissolve 1.2 kg of heptadecafluorodecyltrimethoxysilane in 150 kg of a 60 wt% ethanol aqueous solution, then add 190 kg of the thermally conductive filler, react at 60° C. for 2 h, filter, wash, and dry to obtain two modified thermally conductive fillers; The thermal conductive filler includes aluminum nitride powder and aluminum oxide powder in a weight ratio of 2.1:1. The aluminum nitride powder is composed of two powders with particle sizes of 90μm and 20μm in a weight ratio of 9:11. The aluminum oxide powder is composed of two powders with particle sizes of 10μm and 1.5μm in a weight ratio of 1.5:1. S3. Add one portion of modified thermally conductive filler and 0.03 kg of inhibitor ethynyl cyclyl alcohol to matrix material A, then add 0.45 kg of hydrogenated silicone oil (hydrogen content 0.25%), stir under vacuum for 10 minutes, and release the vacuum to obtain component A of the two-component thermally conductive gel; S4. Add another portion of the modified thermal conductive filler and 0.3 kg of platinum catalyst to the B matrix material, stir under vacuum conditions for 10 minutes, and release the vacuum to obtain the B component of the two-component thermal conductive gel.

[0042] Example 4 A method for preparing a two-component high thermal conductivity gel is different from Example 2 in that the phenyl vinyl siloxane used is the phenyl vinyl siloxane obtained in Preparation Example 2, the amount of hydrogenated silicone oil added is 0.55 kg, and the rest is the same as Example 2.

[0043] Example 5 A method for preparing a two-component high thermal conductivity gel is different from Example 2 in that the phenyl vinyl siloxane used is the phenyl vinyl siloxane obtained in Preparation Example 3, and the rest is the same as Example 2.

[0044] Example 6 A method for preparing a two-component high thermal conductivity gel is different from Example 2 in that the phenyl vinyl siloxane used is the phenyl vinyl siloxane obtained in Preparation Example 4, the amount of hydrogenated silicone oil added is 0.60 kg, and the rest is the same as Example 2.

[0045] Example 7 A method for preparing a two-component high thermal conductivity gel is different from Example 2 in that the phenyl vinyl siloxane used is the phenyl vinyl siloxane obtained in Preparation Example 5, and the rest is the same as Example 2.

[0046] Example 8 A method for preparing a two-component high thermal conductivity gel is different from Example 2 in that the phenyl vinyl siloxane used is the phenyl vinyl siloxane obtained in Preparation Example 6, and the amount of hydrogenated silicone oil added is 0.60 kg. Other aspects are the same as Example 2.

[0047] Example 9 A method for preparing a two-component high thermal conductivity gel is different from Example 2 in that the phenyl vinyl siloxane used is the phenyl vinyl siloxane obtained in Preparation Example 7, and the rest is the same as Example 2.

[0048] Example 10 A method for preparing a two-component high thermal conductivity gel is different from Example 2 in that the phenyl vinyl siloxane used is the phenyl vinyl siloxane obtained in Preparation Example 8, the amount of hydrogenated silicone oil added is 0.60 kg, and the rest is the same as Example 2.

[0049] Comparative Example 1 A method for preparing a two-component high thermal conductivity gel, which differs from Example 2 in that an equal amount of vinyl siloxane is used instead of phenyl vinyl siloxane, the vinyl content in the vinyl siloxane is 0.4%, and the viscosity is 900 mPa·s. Other conditions are the same as Example 2.

[0050] Comparative Example 2 A method for preparing a two-component high thermal conductivity gel, which differs from Example 2 in that an equal amount of vinyl siloxane is used instead of phenyl vinyl siloxane, the vinyl content in the vinyl siloxane is 1.0%, the viscosity is 900 mPa·s, and the amount of hydrogenated silicone oil used is 0.60 kg. All other conditions are the same as in Example 2.

[0051] Comparative Example 3 A method for preparing a two-component high thermal conductivity gel is different from Example 2 in that an equal amount of vinyl siloxane is used instead of phenyl vinyl siloxane, the vinyl content in the vinyl siloxane is 0.4%, and the viscosity is 500 mPa·s. Other conditions are the same as Example 2.

[0052] Comparative Example 4 A method for preparing a two-component high thermal conductivity gel, which differs from Example 2 in that an equal amount of vinyl siloxane is used instead of phenyl vinyl siloxane, the vinyl content in the vinyl siloxane is 1.0%, the viscosity is 500 mPa·s, and the amount of hydrogenated silicone oil used is 0.60 kg. All other conditions are the same as in Example 2.

[0053] Comparative Example 5 A method for preparing a two-component high thermal conductivity gel is different from Example 2 in that the viscosity of the phenyl vinyl siloxane is 900 mPa·s, the phenyl content is 20%, and the vinyl content is 0.2%. Other aspects are the same as Example 2.

[0054] Comparative Example 6 A method for preparing a two-component high thermal conductive gel is different from Example 2 in that the viscosity of the phenyl vinyl siloxane is 900 mPa·s, the phenyl content is 20%, and the vinyl content is 1.5%. Other aspects are the same as Example 2.

[0055] Comparative Example 7 A method for preparing a two-component high thermal conductivity gel is different from Example 2 in that fluorinated silicone oil is not added, and all other steps are the same as Example 2.

[0056] Comparative Example 8 A method for preparing a two-component high thermal conductivity gel is different from Example 2 in that an equal amount of zinc oxide is used instead of aluminum oxide, and all other aspects are the same as Example 2.

[0057] Comparative Example 9 A method for preparing a two-component high thermal conductivity gel, which differs from Example 2 in that alumina is used as a skeleton material and aluminum nitride is used as a gap filling material. Specifically, the aluminum nitride powder is composed of two powders with particle sizes of 5 μm and 1 μm in a weight ratio of 1.5:1, and the alumina powder is composed of two powders with particle sizes of 90 μm and 20 μm in a weight ratio of 9:11. All other conditions are the same as Example 2.

[0058] Performance testing Component A and component B of the thermally conductive gels obtained in the above examples and comparative examples were mixed in a weight ratio of 1:1 and pre-cured at 60°C for 30 minutes. The mixture was then heated to 105°C and cured for 60 minutes. The cured two-component thermally conductive gel was then cooled to room temperature. The thermal conductivity, volume resistivity, tensile strength, 180° peel strength (by bending the gel 180° and stretching it), and hardness were tested. The test results are shown in Table 1.

[0059] The extrusion speed test is as follows: Component A and component B are placed in a 50cc double-round-mouth two-component gel tube in a weight ratio of 1:1. The corresponding Φ5.3mm mixing tube F04 is used as the extrusion mixing tube. The output air pressure is adjusted to 90PSI. The weight obtained by stable extrusion for 60 seconds is the extrusion speed.

[0060] The bonding strength test involved preparing two 100 x 25 x 1 mm aluminum plates. Using a gel tube with a 1:1 mix ratio, the corresponding two-component gel was extruded onto one short side of the aluminum plate. Another aluminum plate was then pressed onto the top layer until the gel thickness reached 1 mm, resulting in a bonded area of ​​10 x 25 mm. The two plates were pre-cured at 60°C for 30 minutes, then heated to 105°C for 60 minutes. The plates were then cooled to room temperature to obtain the bonding material.

[0061] Use the tensile strength test mode, set the tensile speed to 1mm / min, clamp an aluminum plate with the upper and lower clamps respectively, and start the test after clamping. The test data is the bonding strength data.

[0062] Table 1 Thermal Conductive Gel Performance Test Results From Table 1 we can see that: The two-component thermally conductive gels obtained in Examples 1-10 of the present application have excellent thermal conductivity. As the phenyl content gradually decreases, the tensile strength and 180° peel force of the thermally conductive gels also decrease. No residue remains during the peeling process, and the thermally conductive gels have certain adhesive properties while being easy to peel. Furthermore, the thermally conductive gels of the present application examples do not break after being bent 180°, indicating that the gels obtained in the present application have good flexibility, thereby improving the reliability of the thermally conductive gel application.

[0063] Compared with Example 2, when vinyl siloxane was used instead of phenyl vinyl siloxane, the tensile strength, adhesive strength, and 180° peel force of the thermal conductive gel obtained in Comparative Examples 1-4 were significantly reduced. At the same time, particles remained after the gel was peeled, which reduced the service life of the gel.

[0064] Compared with Example 2, in Comparative Examples 5-6, when the vinyl content in the phenyl vinyl siloxane was less than 0.4% and greater than 1.0%, the tensile strength and adhesive strength of the thermally conductive gels obtained in Comparative Examples 5-6 were significantly reduced compared to Example 2, and severe residues were observed after peeling. In addition, the strength of the thermally conductive gel in Comparative Example 5 was too low to achieve 180° bending, resulting in an undetectable peel force. The thermally conductive gel obtained in Comparative Example 6, due to its excessively high vinyl content, was too brittle and broke before being bent 180°, resulting in an undetectable peel force.

[0065] Compared with Example 2, in the absence of fluorinated silicone oil, the 180° peeling force of the gel obtained in Comparative Example 7 is much higher than that in Example 2, indicating that the peeling strength increases in the absence of fluorinated silicone oil. Compared with Example 2, Comparative Example 7 is more difficult to peel.

[0066] Compared with Example 2, after replacing aluminum oxide with an equal amount of zinc oxide, the thermal conductivity of Comparative Example 8 is significantly reduced compared with Example 2; compared with Example 2, when the particle sizes of aluminum nitride and aluminum oxide are exchanged, the thermal conductivity of the gel obtained in Comparative Example 9 is also significantly reduced. This shows that the combined use of aluminum nitride and aluminum oxide in this application effectively improves the thermal conductivity of the gel.

[0067] The embodiments of this specific implementation method are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A two-component high thermal conductivity gel, characterized by: The high thermal conductivity gel comprises component A and component B; The component A comprises the following raw materials in parts by mass: 90-110 parts of phenyl vinyl siloxane, 2-4 parts of fluorinated silicone oil, 4.5-6 parts of hydrogenated silicone oil, 1700-1900 parts of thermal conductive filler, 8-12 parts of surfactant, and 0.1-0.3 parts of inhibitor; The B component comprises the following raw materials in parts by mass: 90-110 parts of phenyl vinyl siloxane, 2-4 parts of fluorinated silicone oil, 1700-1900 parts of thermal conductive filler, 8-12 parts of surfactant, and 1-3 parts of catalyst.

2. The two-component high thermal conductivity gel according to claim 1, characterized in that: The phenyl vinyl siloxane has a phenyl content of 5-20% and a vinyl content of 0.4-1.0%.

3. The two-component high thermal conductivity gel according to claim 2, characterized in that: The phenyl vinyl siloxane is prepared from raw materials phenyl siloxane, methyl siloxane and vinyl siloxane; Preferably, the phenyl vinyl siloxane is prepared by hydrolysis and polycondensation reaction of raw materials phenyl siloxane, methyl siloxane, and vinyl siloxane in a molar ratio of (5-20): (79-94.6): (0.4-1.0); Preferably, the reaction temperature is 100-120°C and the reaction time is 3-5h; Preferably, the reaction catalyst is a basic catalyst; Preferably, the reaction is terminated when the viscosity of the reaction solution is monitored to be 500-1000 mPa·s (25°C).

4. The two-component high thermal conductivity gel according to claim 1, characterized in that: The hydrogen content in the hydrogen-containing silicone oil is 0.1-0.8%.

5. The two-component high thermal conductivity gel according to claim 1, characterized in that: The molecular weight of the fluorinated silicone oil is 20-30KDa; And / or, the surfactant is a silane coupling agent; And / or, the catalyst is at least one of a platinum catalyst, a rhodium catalyst and a palladium catalyst; And / or, the inhibitor is at least one of alkynyl cyclohexanol and alkynol compounds.

6. The two-component high thermal conductivity gel according to claim 1, characterized in that: The thermal conductive filler comprises aluminum nitride powder and aluminum oxide powder in a weight ratio of (1.9-2.1):

1.

7. The two-component high thermal conductivity gel according to claim 6, characterized in that: The particle size of the aluminum nitride powder is 10-90 μm; Preferably, the particle size of the aluminum nitride powder is at least 10-20 μm and 70-90 μm; Preferably, the weight ratio of the aluminum nitride powder with a particle size of 70-90 μm to the aluminum nitride powder with a particle size of 10-20 μm is (8-10):

11.

8. The two-component high thermal conductivity gel according to claim 6, characterized in that: The particle size of the alumina powder is 0.5-10 μm; Preferably, the particle size of the alumina powder includes at least 0.5-1.5 μm and 4-10 μm; Preferably, the weight ratio of the aluminum oxide powder with a particle size of 4-10 μm to the aluminum oxide powder with a particle size of 0.5-1.5 μm is (1-2):

1.

9. A method for preparing a two-component high thermal conductivity gel according to any one of claims 1 to 8, characterized in that: The steps include: S1. preparing a base material by using phenyl vinyl siloxane and fluorinated silicone oil in proportion; S2. Modifying the thermal conductive filler with a surfactant to obtain a modified thermal conductive filler; S3, adding the modified thermal conductive filler and inhibitor in the formula amount to the base material, and then adding hydrogen-containing silicone oil and mixing evenly to prepare component A of the two-component thermal conductive gel; S4. Add the modified thermal conductive filler and catalyst in the formula amount to the base material, mix them evenly, and prepare component B of the two-component thermal conductive gel.

10. The method for preparing the two-component thermally conductive gel according to claim 9, characterized in that: In step S1, the reaction temperature is 155-165° C., and the reaction time is 55-60 minutes at constant temperature under vacuum.

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