High-thermal-conductivity rubber material and preparation method thereof

Abstract

The invention discloses a high-thermal-conductivity rubber material and a preparation method thereof, and belongs to the field of thermal-conductivity materials. The composite material is prepared from the following raw materials in parts by weight: 80-120 parts of rubber powder, 1-20 parts of aluminum nitride, 5-20 parts of carbon nanotubes, 10-90 parts of a high-thermal-conductivity nano composite material and 3-20 parts of a functional aid. The aluminum nitride, the carbon nanotubes and the high-thermal-conductivity nano composite material are added into the rubber powder to serve as the thermal conductive filler, the thermal conductivity of the rubber material is improved, the addition amount of the filler is reduced, the mechanical property of the rubber material is guaranteed, meanwhile, the aluminum nitride, the carbon nanotubes and the high-thermal-conductivity nano composite material can construct a thermal conductive network, and the thermal conductivity of the rubber material is improved. The heat-conducting property of the rubber material is further improved.

Description

Technical Field

[0001] This invention relates to the field of thermally conductive materials, and in particular to a high thermal conductivity rubber material and its preparation method. Background Technology

[0002] High thermal conductivity rubber materials are functional materials that combine rubber elasticity with excellent thermal conductivity, and have important applications in fields such as heat dissipation of electronic devices, new energy vehicles, and aerospace. Traditional rubbers, represented by silicone rubber and EPDM, typically have a thermal conductivity of only 0.1-0.3 W / (mk). The disordered arrangement of molecular chains within these rubbers and severe phonon scattering make heat transfer difficult. With the increasing power of electronic devices, traditional rubbers can no longer meet their heat dissipation requirements, thus placing higher demands on the thermal conductivity of rubber materials.

[0003] Patent CN112080149B discloses a high thermal conductivity silicone rubber material. This material incorporates a graphite / graphene composite material into silicone rubber, using a titanate coupling agent to form a thermally conductive network within the silicone rubber and improve the compatibility between the graphene and graphite fillers and the silicone rubber material. However, the raw materials for this high thermal conductivity rubber material involve spherical alumina of different particle sizes. The spherical filler has poor thermal conductivity, requiring more filler to achieve high thermal conductivity. However, more filler leads to a decrease in the elasticity of the thermally conductive rubber, reducing its mechanical properties. Furthermore, the graphite, graphene, and the copper atoms loaded in their structures significantly increase the electrical conductivity of the silicone rubber, greatly reducing its insulation properties. Moreover, the copper atoms loaded in the graphite and graphene structures are easily oxidized, which significantly affects the various properties of the silicone rubber. Summary of the Invention

[0004] One objective of this invention is to address the problem of insufficient thermal conductivity in current high thermal conductivity rubber materials. This invention provides a high thermal conductivity rubber material by incorporating aluminum nitride, carbon nanotubes, and high thermal conductivity nanocomposite materials into the rubber matrix to improve the thermal conductivity of the rubber material.

[0005] Another objective of this invention is to address the issue that poor dispersion and integration of thermally conductive fillers in rubber leads to high thermal resistance in rubber materials. This invention incorporates functional additives to improve the dispersion and integration of the rubber thermally conductive fillers.

[0006] Another objective of this invention is to provide a method for preparing a high thermal conductivity rubber material, which improves the dispersion and integration of thermally conductive fillers in rubber, while reducing the use of fillers while ensuring thermal conductivity, thereby improving the flexibility of the rubber material.

[0007] This invention provides a high thermal conductivity rubber material, prepared from the following raw materials in parts by weight: 100 parts rubber matrix, 1-20 parts aluminum nitride, 5-20 parts carbon nanotubes, 10-90 parts high thermal conductivity nanocomposite material, and 3-20 parts functional additives. Aluminum nitride contains a crystal lattice, utilizing lattice vibration for heat transfer; it can form localized thermal conductive chains through a "particle bridging" effect, further enhancing overall thermal conductivity; carbon nanotubes are composed of... The tubular structure composed of hybrid carbon atoms has a thermal conductivity mechanism in rubber centered on a one-dimensional thermally conductive network. The axial thermal conduction of CNTs is also dominated by lattice vibrations. Aluminum nitride, carbon nanotubes, and highly thermally conductive nanocomposites are combined with rubber. Small-sized fillers fill the gaps between large-sized fillers, reducing interface defects and forming a multi-level thermally conductive network of "point-line-surface". Aluminum nitride and carbon nanotubes can interact through hydrogen bonds or chemical bonds, reducing the interfacial thermal resistance between fillers and promoting lattice heat transfer. Functional additives assist in processing, further enhancing the performance.

[0008] As a preferred option, the raw materials include: 100 parts of rubber matrix, 10-20 parts of aluminum nitride, 10-15 parts of carbon nanotubes, 50-80 parts of high thermal conductivity nanocomposite material, and 3-20 parts of functional additives.

[0009] Preferably, the rubber matrix is ​​one or more of liquid natural rubber, liquid recycled rubber, natural rubber, styrene-butadiene rubber, and cis-butadiene rubber. The rubber matrix determines the flexibility and processability of the rubber material, and different matrices have different characteristics, so the appropriate rubber matrix can be selected according to the needs.

[0010] Preferably, the carbon nanotube filler is fibrous with an aspect ratio greater than 200; the high thermal conductivity nanocomposite material is one or two of metal-doped silica-alumina carbon black and cellulose nanofibers.

[0011] Preferably, the functional additives include 1-5 parts of silane coupling agent, 1-10 parts of plasticizer, and 1-5 parts of dispersant.

[0012] Preferably, the plasticizer is one or more of the following: epoxy biomass oil, phosphate esters, naphthenic oils, aromatic oils, and cashew nutshell oil. Plasticizers can reduce the intermolecular forces between rubber molecules, improving the dispersibility of fillers and the flexibility of rubber materials.

[0013] Preferably, the dispersant is one or more selected from titanate coupling agents, surfactants, polymer dispersants, and fatty acid salts. The dispersant can reduce the surface energy of the filler through physical adsorption or chemical bonding, thereby improving the dispersibility of the filler in the rubber.

[0014] A method for preparing a high thermal conductivity rubber material includes the following steps: S1. The rubber matrix, aluminum nitride, carbon nanotubes, high thermal conductivity nanocomposite materials, and functional additives are fed into a high-speed mixing tank and stirred. S2. The material after high-speed mixing is sent to a low-speed mixing tank and continuously mixed to obtain premixed rubber. S3. The premixed rubber from the low-stirring tank is fed into the desulfurization extruder for full desulfurization to obtain a uniform high thermal conductivity rubber material. S4. The uniform high thermal conductivity rubber material is fed into an extruder for cooling, and then fed into an extruder for granulation to obtain the high thermal conductivity rubber material.

[0015] Preferably, in step S1, the high-speed mixing tank rotates at a speed of 50–1200 rpm, the mixing temperature is 60–160°C, and the mixing time is 6–25 minutes.

[0016] Preferably, the stirring speed in step S2 is 5-60 rpm, and the temperature is cooled to 35°C in step S4.

[0017] Beneficial effects: The high thermal conductivity rubber material of the present invention uses aluminum nitride filler that is chemically bonded to the rubber, which reduces thermal resistance and reduces the contact between aluminum nitride and water, thus reducing the possibility of hydrolysis. Since aluminum nitride has high thermal conductivity, the use of filler can be reduced, thus avoiding affecting the flexibility of the rubber material.

[0018] By adding functional additives and coating aluminum nitride with silane coupling agents, the interfacial bonding between aluminum nitride and rubber is further improved; the high aspect ratio of carbon nanotubes makes it easy to form physical entanglement in rubber, forming a strong interaction with the rubber molecular chain, inhibiting filler agglomeration and enhancing filler dispersion.

[0019] The dispersibility and thermal conductivity of the filler are improved by incorporating nanocomposite materials. Finally, the properties of the rubber material are adjusted using plasticizers and dispersants, thereby obtaining a rubber material with high thermal conductivity while ensuring its flexibility and mechanical properties. Detailed Implementation

[0020] To better illustrate the technical effects of the present invention, the following analysis is conducted in conjunction with specific embodiments and comparative examples.

[0021] General Implementation Examples: A high thermal conductivity rubber material is made from the following raw materials in parts by weight: 100 parts rubber matrix, 10-20 parts aluminum nitride, 10-20 parts carbon nanotubes, 10-30 parts nanocomposite materials, 1-5 parts silane coupling agent, 1-10 parts plasticizer, and 1-5 parts dispersant.

[0022] A method for preparing a high thermal conductivity rubber material is as follows: S1. Add the rubber matrix and all components to a high-speed mixing tank according to the specified proportions and stir at high speed to ensure uniform dispersion, utilizing friction to generate heat. The high-speed mixing tank should be set at a speed of 50–1200 rpm, with the temperature controlled at 60–160°C, for a duration of 6–25 minutes.

[0023] S2. The material after high-speed mixing is fed into a low-speed mixing tank and continuously mixed to prepare for continuous desulfurization in the subsequent desulfurization unit. The speed of the low-speed mixing tank is 5-60 rpm.

[0024] S3. The premixed rubber in the low-temperature stirring tank is fed into the desulfurization extruder for full desulfurization, and the organic rubber component is uniformly coated on the surface of the high thermal conductivity material particles by mechanochemical action. S4. The desulfurized high thermal conductivity rubber material is fed into an extruder and cooled to below 35°C. Then it is fed into an extruder for granulation to obtain the high thermal conductivity rubber material.

[0025] Example 1 A high thermal conductivity rubber material is made from the following raw materials in parts by weight: 100 parts rubber matrix, 1 part aluminum nitride, 5 parts carbon nanotubes, 10 parts high thermal conductivity nanocomposite material, 1 part silane coupling agent, 2 parts epoxidized soybean oil, and 1 part titanate coupling agent.

[0026] The formulations in this embodiment use the minimum required proportions, resulting in lower costs, but the thermal conductivity is not expected to be very high.

[0027] A method for preparing a high thermal conductivity rubber material is as follows: S1. Add the rubber matrix and all components to a high-speed mixing tank according to the specified proportions and stir at high speed to ensure uniform dispersion, utilizing friction to generate heat. The high-speed mixing tank rotates at 600 rpm, maintains the temperature at 100℃, and operates for 20 minutes.

[0028] S2. The material after high-speed mixing is fed into a low-speed mixing tank and continuously mixed to prepare for continuous desulfurization in the subsequent desulfurization unit. The speed of the low-speed mixing tank is 30 rpm.

[0029] S3. The premixed rubber in the low-temperature stirring tank is fed into the desulfurization extruder for full desulfurization, and the organic rubber component is uniformly coated on the surface of the high thermal conductivity material particles by mechanochemical action. S4. The desulfurized high thermal conductivity rubber material is fed into an extruder and cooled to below 35°C. Then it is fed into an extruder for granulation to obtain the high thermal conductivity rubber material.

[0030] Example 2 Raw material composition: 100 parts rubber matrix, 10 parts aluminum nitride, 10 parts carbon nanotubes, 50 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts epoxidized soybean oil, and 3 parts titanate coupling agent.

[0031] The proportions of each component in this embodiment are moderate, with aluminum nitride, carbon nanotubes, and high thermal conductivity nanocomposite materials in relatively close proportions, suggesting good thermal conductivity and moderate cost. This formulation uses epoxidized soybean oil as a accelerator. Epoxidized soybean oil is an epoxy compound plasticizer; the epoxy groups in its molecules can interact with polar groups on rubber molecular chains, weakening the intermolecular forces and making the chains slide more easily, thus improving the plasticity and flexibility of the rubber. The titanate coupling agent contains alkoxy groups and long-chain organic groups. The alkoxy groups react with the hydroxyl groups on the surface of the inorganic filler to form chemical bonds, creating a monomolecular film. The long-chain organic groups entangle with the rubber molecules, enhancing the bonding force between the filler and the rubber matrix. This structure lowers the surface energy of the filler, giving it rubber-friendly properties and improving its dispersion ability in the rubber. Through the dual effects of chemical bonds and physical entanglement, the titanate coupling agent effectively improves the interfacial compatibility between the filler and the rubber.

[0032] The preparation method in this embodiment is the same as that in Example 1.

[0033] Example 3 Raw material composition: 100 parts rubber matrix, 20 parts aluminum nitride, 15 parts carbon nanotubes, 80 parts high thermal conductivity nanocomposite material, 5 parts silane coupling agent, 10 parts epoxidized soybean oil, and 5 parts titanate coupling agent.

[0034] In this embodiment, the maximum proportion of each component is added, which is expected to result in higher thermal conductivity, but also higher cost.

[0035] The preparation method in this embodiment is the same as that in Example 1.

[0036] Example 4 Raw material composition: 100 parts rubber matrix, 14 parts aluminum nitride, 10 parts carbon nanotubes, 50 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts epoxidized soybean oil, and 3 parts titanate coupling agent.

[0037] The preparation method in this embodiment is the same as that in Example 1.

[0038] Example 5 Raw material composition: 100 parts rubber matrix, 16 parts aluminum nitride, 10 parts carbon nanotubes, 50 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts epoxidized soybean oil, and 3 parts titanate coupling agent.

[0039] The preparation method in this embodiment is the same as that in Example 1.

[0040] Example 6 Raw material composition: 100 parts rubber matrix, 18 parts aluminum nitride, 10 parts carbon nanotubes, 50 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts epoxidized soybean oil, and 3 parts titanate coupling agent.

[0041] The preparation method in this embodiment is the same as that in Example 1.

[0042] Example 7 Raw material composition: 100 parts rubber matrix, 10 parts aluminum nitride, 15 parts carbon nanotubes, 50 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts epoxidized soybean oil, and 3 parts titanate coupling agent.

[0043] The preparation method in this embodiment is the same as that in Example 1.

[0044] Example 8 Raw material composition: 100 parts rubber matrix, 20 parts aluminum nitride, 20 parts carbon nanotubes, 50 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts epoxidized soybean oil, and 3 parts titanate coupling agent.

[0045] The preparation method in this embodiment is the same as that in Example 1.

[0046] Example 9 Raw material composition: 100 parts rubber matrix, 10 parts aluminum nitride, 10 parts carbon nanotubes, 20 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts epoxidized soybean oil, and 3 parts titanate coupling agent.

[0047] The preparation method in this embodiment is the same as that in Example 1.

[0048] Example 10 Raw material composition: 100 parts rubber matrix, 10 parts aluminum nitride, 10 parts carbon nanotubes, 30 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts epoxidized soybean oil, and 3 parts titanate coupling agent.

[0049] The preparation method in this embodiment is the same as that in Example 1.

[0050] Example 11 Raw material composition: 100 parts rubber matrix, 10 parts aluminum nitride, 10 parts carbon nanotubes, 40 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts epoxidized soybean oil, and 3 parts titanate coupling agent.

[0051] The preparation method in this embodiment is the same as that in Example 1.

[0052] Example 12 Raw material composition: 100 parts rubber matrix, 10 parts aluminum nitride, 10 parts carbon nanotubes, 60 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts epoxidized soybean oil, and 3 parts titanate coupling agent.

[0053] The preparation method in this embodiment is the same as that in Example 1.

[0054] Example 13 Raw material composition: 100 parts rubber matrix, 10 parts aluminum nitride, 10 parts carbon nanotubes, 70 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts epoxidized soybean oil, and 3 parts titanate coupling agent.

[0055] The preparation method in this embodiment is the same as that in Example 1.

[0056] Example 14 Raw material composition: 100 parts rubber matrix, 10 parts aluminum nitride, 10 parts carbon nanotubes, 50 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts naphthenic oil, and 3 parts titanate coupling agent.

[0057] Naphthenic oils are mainly composed of cycloalkanes and are a type of physical plasticizer. Their molecular structure is relatively regular, allowing them to insert into the spaces between rubber molecular chains, increasing the intermolecular distance and weakening the intermolecular forces. This enhances the mobility of the rubber molecular chains and improves the plasticity and processing performance of the rubber.

[0058] The preparation method in this embodiment is the same as that in Example 1.

[0059] Example 15 Raw material composition: 100 parts rubber matrix, 10 parts aluminum nitride, 10 parts carbon nanotubes, 50 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts aromatic oil, and 3 parts titanate coupling agent.

[0060] Aromatic oil is a petroleum-based plasticizer, mainly composed of aromatic hydrocarbons. The aromatic ring structure in its molecule can also interact with the polar groups on the rubber molecular chain, shielding the interaction forces between rubber molecules, thereby reducing the interaction forces between rubber molecules, making the molecular chain more mobile, and improving the plasticity and processing performance of rubber.

[0061] The preparation method in this embodiment is the same as that in Example 1.

[0062] Example 16 Raw material composition: 100 parts rubber matrix, 10 parts aluminum nitride, 10 parts carbon nanotubes, 50 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts cashew nut shell oil, and 3 parts titanate coupling agent.

[0063] Cashew nut shell oil is a bio-based plasticizer. Its molecular structure contains a variety of functional groups that can interact with rubber molecular chains, thereby weakening the interaction forces between rubber molecular chains, making the molecular chains easier to slide, and improving plasticity and processing performance.

[0064] The preparation method in this embodiment is the same as that in Example 1.

[0065] Example 17 Raw material composition: 100 parts rubber matrix, 10 parts aluminum nitride, 10 parts carbon nanotubes, 50 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts epoxidized soybean oil, and 3 parts surfactant.

[0066] Surfactants can adsorb at the liquid-solid interface, reducing the interfacial free energy and allowing solid fillers to be uniformly dispersed in the liquid, preventing filler re-aggregation. In rubber production, surfactants can uniformly and stably disperse rubber particles, effectively improving the interfacial compatibility between the filler and the rubber matrix.

[0067] The preparation method in this embodiment is the same as that in Example 1.

[0068] Example 18 Raw material composition: 100 parts rubber matrix, 10 parts aluminum nitride, 10 parts carbon nanotubes, 50 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts epoxidized soybean oil, and 3 parts polymer dispersant.

[0069] Polymer dispersants have long polymer chains that can adhere to the filler surface through physical adsorption and chemical bonding. These polymer chains can move freely in the rubber matrix, thereby reducing the interfacial tension between the filler and rubber molecules. Through steric hindrance, polymer dispersants can prevent the agglomeration of filler particles and maintain the uniform dispersion of the filler in the rubber.

[0070] The preparation method in this embodiment is the same as that in Example 1.

[0071] Table 1 Raw material ratios for Examples 1-18

[0072] Examples 1-3 are studies on different proportions of the same formulation. Example 3 is expected to have the best effect, Example 1 the worst, and Example 2 the best cost-effectiveness. Examples 2 and 4-8 are studies on the addition amounts of aluminum nitride and carbon nanotubes; Examples 2 and 9-13 are studies on the addition amounts of high thermal conductivity nanocomposite materials. Examples 2 and 14-16 are studies on the addition of plasticizers such as epoxidized soybean oil, aromatic oil, naphthenic oil, and cashew nut shell oil; Examples 2 and 17-18 are studies on titanate coupling agents, surfactants, polymer dispersants, and concentrated dispersants.

[0073] Comparative Example 1 The raw materials for this comparative example are: 100 parts rubber matrix, 10 parts carbon nanotubes, 50 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts epoxidized soybean oil, and 3 parts titanate coupling agent.

[0074] This comparison ratio lacks aluminum nitride, which is an additive that improves thermal conductivity, resulting in a decrease in thermal conductivity. Additionally, since aluminum nitride is also an insulating material, its insulation properties will also decrease.

[0075] The preparation method is the same as that in Example 1.

[0076] Comparative Example 2 The raw materials for this comparative example are: 100 parts rubber matrix, 10 parts aluminum nitride, 50 parts high thermal conductivity nanocomposite material, 3 parts silane coupling agent, 4 parts epoxidized soybean oil, and 3 parts titanate coupling agent. The absence of carbon nanotubes will reduce mechanical properties. Carbon nanotubes have high tensile strength, which can significantly improve the tensile strength, tear strength, and abrasion resistance of rubber.

[0077] The preparation method is the same as that in Example 1.

[0078] Comparative Example 3 The raw materials for this comparative example are: 100 parts rubber matrix, 10 parts aluminum nitride, 10 parts carbon nanotubes, 50 parts alumina-graphene composite, 3 parts silane coupling agent, 4 parts epoxidized soybean oil, and 3 parts titanate coupling agent.

[0079] In this comparative example, the high thermal conductivity nanocomposite material was replaced with an alumina-graphene composite. Compared with the high thermal conductivity nanocomposite material, the alumina-graphene composite material constructs a fast thermally conductive network, the alumina fills the interfacial pores, and synergistically improves the thermal conductivity of the rubber. The high thermal conductivity nanocomposite material, silica-alumina-carbon black, provides mechanical property reinforcement and improves thermal conductivity, while cellulose nanofibers enhance the tensile strength of the rubber.

[0080] The preparation method is the same as that in Example 1.

[0081] Comparative Example 4 The raw materials for this comparative example are: 100 parts rubber matrix, 10 parts aluminum nitride, 10 parts carbon nanotubes, and 50 parts high thermal conductivity nanocomposite materials.

[0082] This comparative example lacks silane coupling agent, epoxidized soybean oil, and titanate coupling agent; the absence of processing aids will result in the raw materials not performing at their best.

[0083] The preparation method is the same as in Example 1.

[0084] Table 2 Raw material ratios for Comparative Examples 1-4

[0085] Performance tests were conducted on Examples 1-18 and Comparative Examples 1-4:

[0086] Thermal conductivity measurement:

[0087] Thermal conductivity was determined using the laser flare method: a thin sheet of high thermal conductivity rubber material with a diameter of 10 mm and a thickness of 1 mm was taken, the back of the sample was irradiated with a laser pulse, and the temperature rise curve of the front was recorded by an infrared detector. The thermal diffusivity was calculated, and the thermal conductivity was calculated by multiplying the thermal diffusivity, specific heat capacity and density.

[0088] Tensile strength test:

[0089] The tensile properties of rubber materials were determined according to ASTM D412 standard.

[0090] Volume resistivity measurement:

[0091] The volume resistivity of rubber materials was determined according to IEC 60093 standard.

[0092] The specific test data is shown in the table below:

[0093] Table 3 Performance tests of Examples 1-18. Thermal conductivity (W / m·K) Tensile strength (MPa) <![CDATA[Volume resistivity (10 14 Ω·cm)]]> Example 1 1.61 4.51 3.2 Example 2 2.65 6.90 8.5 Example 3 3.02 7.39 9.8 Example 4 2.69 5.21 9.1 Example 5 2.74 5.20 9.3 Example 6 2.84 5.19 9.5 Example 7 2.99 7.43 8.5 Example 8 3.06 7.91 10.1 Example 9 1.74 6.80 8.1 Example 10 1.86 6.85 8.3 Example 11 2.24 6.90 8.4 Example 12 2.79 6.92 8.7 Example 13 2.96 6.94 8.9 Example 14 2.66 6.91 8.5 Example 15 2.65 6.90 8.5 Example 16 5.63 6.89 8.4 Example 17 2.67 6.91 8.5 Example 18 2.68 6.92 8.5

[0094] The amount of additive added in Example 1 was too small, resulting in low performance in the test results. Example 8 showed the best rubber material performance with the appropriate amount of additive. The aluminum nitride modified with the silane coupling agent improved the thermal conductivity and insulation properties of the rubber. Because the modified aluminum nitride filler bonds with the rubber through chemical bonds, it reduces the thermal resistance of the rubber material, thus ensuring high thermal conductivity. In addition, carbon nanotubes and high thermal conductivity nanocomposites both have a significant impact on the thermal conductivity of the rubber material. Examples 2, 7, and 8 studied the effect of different amounts of carbon nanotubes on the rubber properties; carbon nanotubes have a significant impact on tensile strength. Examples 2, 9-13 studied the amount of high thermal conductivity nanocomposites added. With the addition of high thermal conductivity nanocomposites, thermal conductivity, tensile strength, and resistivity all increased.

[0095] Performance tests of Comparative Examples 1-4. Thermal conductivity (W / m·K) Tensile strength (MPa) <![CDATA[Volume resistivity (10 14 Ω·cm)]]> Comparative Example 1 2.12 6.40 8.1 Comparative Example 2 2.34 5.87 7.9 Comparative Example 3 1.98 6.21 / Comparative Example 4 2.51 6.75 8.4

[0096] Comparative Example 1 lacked aluminum nitride, resulting in a significant decrease in thermal conductivity. The absence of aluminum nitride reduced interfacial thermal resistance, preventing the formation of a synergistic thermally conductive network with carbon nanotubes. Comparative Example 2 lacked carbon nanotubes, leading to a significant decrease in mechanical properties due to the missing network-building ability. The absence of physical reinforcing phases meant that carbon nanotubes restricted chain segment movement, inhibited excessive deformation under stress, and improved tensile and tear strength. Comparative Example 3 replaced the high-nano composite material with an alumina-graphite composite material, resulting in a slight decrease in thermal conductivity. The synergistic effect between the alumina-graphite composite material and aluminum nitride and carbon nanotubes was minimal, with mutual interference, particularly in insulation properties. Comparative Example 3 thus became a conductive material. Comparative Example 4 lacked processing aids, leading to a decrease in various properties.

[0097] Unless otherwise specified, the raw materials and equipment used in this invention are all commonly used in the field; unless otherwise specified, the methods used in this invention are all conventional methods in the field.

[0098] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, alterations, and equivalent transformations made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the technical solution of the present invention.

Claims

1. A high thermal conductivity rubber material, made from the following raw materials in parts by weight: 80-120 parts rubber powder, 1-20 parts aluminum nitride, 5-20 parts carbon nanotubes, and 10-90 parts high thermal conductivity nanocomposite materials.

2. The high thermal conductivity rubber material according to claim 1, characterized in that, Raw materials include: 100-110 parts of adhesive powder, 10-20 parts of aluminum nitride, 10-15 parts of carbon nanotubes, 50-80 parts of high thermal conductivity nanocomposite materials, and 3-20 parts of functional additives.

3. A high thermal conductivity rubber material according to claim 1 or 2, characterized in that: The rubber powder is one or more of liquid natural rubber, liquid recycled rubber, natural rubber, styrene-butadiene rubber, and cis-butadiene rubber.

4. A high thermal conductivity rubber material according to claim 1 or 2, characterized in that: The carbon nanotube filler is fibrous in shape with an aspect ratio greater than 200; the high thermal conductivity nanocomposite material is one or two of metal-doped silica-alumina carbon black and cellulose nanofibers.

5. The high thermal conductivity rubber material according to claim 2, characterized in that: The functional additives include 1-5 parts of silane coupling agent, 1-10 parts of plasticizer, and 1-5 parts of dispersant.

6. The high thermal conductivity rubber material according to claim 5, characterized in that: The plasticizer is one or more of the following: epoxy biomass oil, naphthenic oil, aromatic oil, and cashew nut shell oil.

7. The high thermal conductivity rubber material according to claim 5, characterized in that, The dispersant is one or more of the following: titanate coupling agent, surfactant, polymer dispersant, and fatty acid salt.

8. A method for preparing a high thermal conductivity rubber material, characterized in that, A high thermal conductivity rubber material according to any one of claims 1-6, comprising the following steps: S1. Add the adhesive powder, aluminum nitride, carbon nanotubes, high thermal conductivity nanocomposite materials, and functional additives into a high-speed mixing tank and stir. S2. The material after high-speed mixing is fed into a low-speed mixing tank and continuously mixed to obtain premixed rubber powder. S3. The premixed rubber powder from the low-stirring tank is fed into the desulfurization extruder for full desulfurization to obtain a uniform high thermal conductivity rubber material. S4. The uniform high thermal conductivity rubber material is fed into an extruder for cooling, and then fed into an extruder for granulation to obtain the high thermal conductivity rubber material.

9. The method for preparing a high thermal conductivity rubber material according to claim 8, characterized in that, In step S1, the high-speed mixing tank rotates at 50~1200 rpm, the mixing temperature is 60~160℃, and the mixing time is 6~25 minutes.

10. The method for preparing a high thermal conductivity rubber material according to claim 8, characterized in that, In step S2, the low-speed stirring speed is 5~60 rpm, and in step S4, the temperature is cooled to 35℃.

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