Heat-conducting and wave-absorbing material composition and preparation method of heat-conducting and wave-absorbing material

Abstract

The invention discloses a heat-conducting wave-absorbing material composition which comprises a component A and a component B. The component A is prepared from, by mass, 3.5-5 parts of silicone oil, 30-50 parts of graphene modified spherical silicon carbide, 40-50 parts of heat-conducting filler and 0.02-0.03 part of catalyst. The component B is prepared from the following components in parts by mass: 3.5 to 5 parts of silicone oil, 30 to 50 parts of graphene modified spherical silicon carbide, 40 to 50 parts of heat-conducting filler and 0.01 to 0.02 part of inhibitor. The heat-conducting and wave-absorbing material prepared from the heat-conducting and wave-absorbing material composition provided by the invention has ultrahigh heat-conducting property, and can effectively restrain the electromagnetic problem of the 0.1-8 GHz frequency band in communication equipment; after the graphene modified silicon carbide is applied to the product, the dielectric loss can be obviously improved, and the reduction of the proportion of the magnetic absorbent with relatively poor heat conductivity and the improvement of the heat-conducting property during product design are facilitated.

Description

Technical Field

[0001] The present application relates to the field of material technology, and in particular to a thermal conductive wave absorbing material composition and a method for preparing the thermal conductive wave absorbing material. Background Art

[0002] Thermally conductive and absorbing materials are materials that conduct heat and absorb electromagnetic waves simultaneously, offering a wide range of applications. They play a crucial role in electronics, communications, aerospace, medical devices, and other fields, and have therefore garnered significant attention.

[0003] Most of the thermally conductive and absorbing materials provided in the prior art have low thermal conductivity. US20230320049A1 provides a thermally conductive and absorbing material composed of silicon carbide, a magnetic absorber, aluminum oxide, and a polymer substrate. The thermal conductivity coefficient of the thermally conductive and absorbing material provided is 2-4 W / (m·K), which is relatively low in thermal conductivity.

[0004] CN117844250A provides a thermally conductive and absorbing material. This technology uses a thermally conductive and absorbing powder with a carbon-based material as a core and a silicon carbide shell to fill organic silica gel to obtain the thermally conductive and absorbing material. The carbon-based material is one or more of graphite, graphite oxide, graphene, carbon nanotubes, or carbon fibers. According to its embodiments, the thermally conductive and absorbing material provided by this technology has a thermal conductivity of 3.5 to 5.7 W / (m·K), which has good absorbing performance, but low thermal conductivity.

[0005] Therefore, providing a thermally conductive and absorbing material with a simple preparation method and ultra-high thermal conductivity (≥10 W / (m·K)) is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the present application provides a thermally conductive and absorbing material composition with ultra-high thermal conductivity (≥10 W / (m·K)), simple raw material preparation and low specific surface area, which facilitates material filling.

[0007] The present application provides a thermally conductive and wave-absorbing material composition, comprising component A and component B, wherein component A comprises, by mass, 3.5 to 5 parts of silicone oil, 30 to 50 parts of graphene-modified spherical silicon carbide, 40 to 50 parts of thermally conductive filler, and 0.02 to 0.03 parts of a catalyst; and component B comprises, by mass, 3.5 to 5 parts of silicone oil, 30 to 50 parts of graphene-modified spherical silicon carbide, 40 to 50 parts of thermally conductive filler, and 0.01 to 0.02 parts of an inhibitor.

[0008] This application prepares a thermally conductive and absorbing material composition using components A and B as raw materials. Component A comprises, by weight, 3.5 to 5 parts silicone oil, 30 to 50 parts graphene-modified spherical silicon carbide, 40 to 50 parts thermally conductive filler, and 0.02 to 0.03 parts catalyst; and component B comprises, by weight, 3.5 to 5 parts silicone oil, 30 to 50 parts graphene-modified spherical silicon carbide, 40 to 50 parts thermally conductive filler, and 0.01 to 0.02 parts inhibitor. This application modifies micron-sized spherical silicon carbide with graphene, leveraging the thermal conductivity of both silicon carbide and graphene while simultaneously increasing the product's dielectric loss to reduce the amount of magnetic absorber, which has poor thermal conductivity. This achieves both excellent absorbing performance and ultra-high thermal conductivity. The thermally conductive and absorbing material composition described in this application boasts ultra-high thermal conductivity of 10-12 W / (m·K), effectively addressing electromagnetic interference in the 0.1-8 GHz frequency band while providing efficient heat transfer for devices. By optimizing the selection of components, this application reduces the use of iron-based absorbers while meeting absorption requirements and improving thermal conductivity.

[0009] The thermal conductive and wave absorbing material composition described in this application includes silicone oil. The silicone oil in component A and component B includes, but is not limited to, vinyl silicone oil and / or hydrogenated silicone oil. This application has no special requirements for the selection of silicone oil. The mass fractions of silicone oil in component A and component B are independently 3.5 to 5 parts, and can be 3.5 parts, 3.7 parts, 3.9 parts, 4 parts, 4.2 parts, 4.4 parts, 4.5 parts, 4.6 parts, 4.8 parts, or 5 parts. In some specific implementations, the silicone oil in component B includes vinyl silicone oil and hydrogenated silicone oil, and the mass fractions include: 4 to 4.15 parts vinyl silicone oil and 0.3 to 0.4 parts hydrogenated silicone oil, preferably 4.1 to 4.12 parts vinyl silicone oil and 0.38 to 0.4 parts hydrogenated silicone oil.

[0010] The thermal conductive and wave absorbing material composition described in the present application includes graphene-modified spherical silicon carbide. In some specific implementations, the specific surface area of ​​the graphene-modified spherical silicon carbide in component A and component B is independently 0.2 m 2 / g to 1 m 2 / g; the particle size of the graphene-modified spherical silicon carbide in component A and component B is independently 10μm to 100μm, preferably 20μm to 70μm. In some specific implementations, the spherical silicon carbide in the graphene-modified spherical silicon carbide in component A and component B independently includes large-particle spherical silicon carbide and / or small-particle spherical silicon carbide, the particle size of the large-particle spherical silicon carbide is 70μm, and the particle size of the small-particle spherical silicon carbide is 20μm. In some specific implementations, the preparation method of the graphene-modified spherical silicon carbide in component A and component B independently includes: mixing spherical silicon carbide with graphene, ball milling, and obtaining graphene-modified spherical silicon carbide. In some specific implementations, the spherical silicon carbide is obtained by spray granulation of silicon carbide; the mass ratio of the graphene to the spherical silicon carbide is independently (0.05-1): (95-100), preferably 0.1:100; the ball milling time is 4 to 10 hours, and can be 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, or 10 hours. In some specific implementations, the thickness of the graphene in the graphene-modified spherical silicon carbide in component A and component B is independently 1 nm to 4 nm; the flake diameter of the graphene is independently 1 μm to 5 μm; and the specific surface area of ​​the graphene is independently 50 m 2 / g to 85m 2 / g. This application uses pre-prepared graphene, and the specifications of the graphene (thickness, flake diameter, specific surface area, etc.) are more controllable, which is more conducive to the dispersion of materials. When mixed and modified with silicon carbide, it can be completed by ball milling with low energy (rotation speed ≤ 100 RPM, duration 4~10h), which improves efficiency and reduces damage to the surface of the spherical silicon carbide during the ball milling process. Combined with micron-sized spherical silicon carbide, the obtained graphene-modified silicon carbide powder has a lower specific surface area, which is more conducive to material filling and the realization of ultra-high thermal conductivity. Silicon carbide and graphene are both highly thermally conductive materials and have wave absorption effects. In particular, after silicon carbide is modified with graphene, its application in products can significantly increase dielectric loss, which is beneficial to reducing the proportion of magnetic absorbers with poor thermal conductivity in product design, and is beneficial to improving the thermal conductivity of the product. After modification with micron-sized spherical silicon carbide, the specific surface area is lower, which is not only easier to fill, but also more conducive to improving thermal conductivity.

[0011] The thermally conductive and absorbing material composition described herein includes a thermally conductive filler. The thermally conductive fillers in Component A and Component B independently include, but are not limited to, one or more of aluminum oxide, aluminum nitride, boron nitride, or zinc oxide. This application has no specific requirements for the selection of thermally conductive fillers. In some specific implementations, the particle size of the thermally conductive fillers in Component A and Component B independently ranges from 1 μm to 96 μm. The mass fractions of the thermally conductive fillers in Component A and Component B independently range from 40 to 50 parts, and may be 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 parts.

[0012] The thermally conductive and wave-absorbing material composition described herein includes a catalyst. The catalyst in Component A includes, but is not limited to, a platinum catalyst. The present application has no specific requirements for the catalyst selection. In some specific implementations, the platinum content of the platinum catalyst is 0.05%. The mass fraction of the catalyst in Component A ranges from 0.02 to 0.03 parts, and may include 0.02, 0.022, 0.024, 0.026, 0.028, or 0.03 parts.

[0013] The thermally conductive and wave-absorbing material composition described herein includes an inhibitor. The inhibitor in Component B includes, but is not limited to, one or more of methyltris(1,1-dimethyl-1-ethynylmethoxy)silane, vinyltris(1,1-dimethyl-1-ethynylmethoxy)silane, phenyltris(1,1-dimethyl-1-ethynylmethoxy)silane, 3-methyl-1-butyn-3-ol, 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, N,N,N',N'-tetraallylterephthalamide, or monoallyl maleate. The present application has no specific requirements for the selection of the inhibitor. The weight fraction of the inhibitor in Component B is 0.01 to 0.02 parts, and may be 0.01, 0.012, 0.014, 0.015, 0.016, 0.018, or 0.02 parts.

[0014] The thermally conductive and absorbing material composition described herein also includes an iron-based absorber. In some specific implementations, the iron-based absorber includes, but is not limited to, iron-based amorphous alloy powder. This application has no specific requirements for the selection of the iron-based absorber. The particle size of the iron-based absorber is 1 μm to 10 μm. The iron-based absorber is present in an amount of 9 to 18 parts by weight, and may be 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 parts by weight.

[0015] In some specific implementations, the volume ratio of component A to component B is (0.8-1.2):1, preferably 1:1.

[0016] The present application also provides a method for preparing a thermally conductive and wave-absorbing material, comprising:

[0017] Mixing graphene-modified spherical silicon carbide, a thermally conductive filler, silicone oil, and a catalyst to obtain component A;

[0018] Mixing graphene-modified spherical silicon carbide, a thermally conductive filler, silicone oil, and an inhibitor to obtain component B;

[0019] Component A and component B are mixed and cured to obtain a heat-conducting and wave-absorbing material.

[0020] The present application first prepares graphene-modified spherical silicon carbide. In some specific implementations, silicon carbide is spray-granulated to obtain spherical silicon carbide; the spherical silicon carbide is mixed with graphene and ball-milled to obtain graphene-modified spherical silicon carbide. In some specific implementations, the mass ratio of graphene to spherical silicon carbide is (0.05-1): (95-100); and the ball milling time is 4 to 10 hours. Spheroidization can improve the filling effect of the powder, which is conducive to high filling when making products. At the same time, the preparation method selects the use of graphene with a relatively low specific surface area and the required dosage is relatively low, so that the modified spherical silicon carbide has better filling properties, which is conducive to the realization of ultra-high thermal conductivity.

[0021] The present application then mixes graphene-modified spherical silicon carbide, a thermally conductive filler, silicone oil, and a catalyst to obtain component A. In some specific implementations, the mixing is performed with stirring for 20 to 30 minutes, preferably 30 minutes, and under vacuum conditions at a vacuum level of 4 Pa ​​to 10 Pa. In some specific implementations, the silicone oil includes, but is not limited to, vinyl silicone oil and / or hydrogenated silicone oil. The present application has no specific requirements for the selection of silicone oil.

[0022] The present application then mixes graphene-modified spherical silicon carbide, a thermally conductive filler, silicone oil, and an inhibitor to obtain component B. In some specific implementations, the mixing is performed with stirring for 20 to 30 minutes, preferably 30 minutes, and under vacuum conditions at a vacuum level of 4 Pa ​​to 10 Pa. In some specific implementations, the silicone oil includes, but is not limited to, vinyl silicone oil and / or hydrogenated silicone oil. The present application has no specific requirements for the selection of silicone oil.

[0023] This application then mixes component A and component B and cures them to produce a thermally conductive, wave-absorbing material. In some specific implementations, the curing temperature is 120°C to 130°C, preferably 125°C, and the curing time is 20 to 40 minutes. In some specific implementations, the volume ratio of component A to component B is (0.8-1.2):1, preferably 1:1.

[0024] The thermally conductive and absorbing material composition provided in the present application has ultra-high thermal conductivity, a thermal conductivity coefficient of 10~12 W / (m·K), a hardness of 65±5 Shore OO after curing, and has efficient wave absorbing performance, which can effectively suppress electromagnetic problems in the 0.1~8GHz frequency band in communication equipment; silicon carbide and graphene are both highly thermally conductive materials and have wave absorbing effects. In particular, after silicon carbide is modified with graphene, its application in products can significantly improve dielectric loss, thereby helping to reduce the proportion of magnetic absorbers with poor thermal conductivity in product design, and improving the thermal conductivity of the product; the specific surface area of ​​the graphene-modified spherical silicon carbide in the raw materials of the thermally conductive and absorbing material composition is less than 1 m 2 / g, has good filling performance, which is conducive to the realization of ultra-high thermal conductivity. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A flow chart for preparing the thermal conductive and wave absorbing material provided in this application;

[0026] Figure 2 This is a diagram showing the application test results of the test fixture for the thermal conductive and wave absorbing material provided in Example 1 of the present application;

[0027] Figure 3 This is a diagram showing the application test results of the test fixture for the thermal conductive and wave absorbing material provided in Example 2 of the present application;

[0028] Figure 4 This is a diagram showing the application test results of the test tooling for the thermal conductive and wave absorbing material provided in Example 3 of the present application;

[0029] Figure 5 This is a diagram showing the application test results of the test tooling for the thermal conductive and wave absorbing material provided in Comparative Example 1 of this application. DETAILED DESCRIPTION

[0030] It should be understood that the expression "one or more of" includes individually each of the items recited after the expression and various combinations of two or more of the recited items, unless otherwise apparent from the context and usage. The expression "and / or" in conjunction with three or more recited items should be understood to have the same meaning, unless otherwise apparent from the context.

[0031] The terms "comprising", "having" or "containing", including their grammatical synonyms, should generally be understood as open and non-restrictive, e.g., not excluding other unrecited elements or steps, unless otherwise specifically stated or understood from the context.

[0032] It should be understood that the order of steps or the order in which certain actions are performed is not important as long as the application remains operable. Additionally, two or more steps or actions may be performed simultaneously.

[0033] The use of any and all examples or exemplary language, such as "such as" or "including," herein is intended merely to better illustrate the present application and does not limit the scope of the present application unless otherwise claimed. No language in this specification should be construed as indicating any non-claimed element as essential to the practice of the present application.

[0034] In addition, the numerical ranges and parameters used to define this application are approximate values. The relevant numerical values ​​in the specific examples have been presented as accurately as possible. However, any numerical value inherently inevitably contains standard deviations due to individual testing methods. Therefore, unless otherwise expressly stated, it should be understood that all ranges, amounts, values, and percentages used in this disclosure are modified by the word "about." As used herein, "about" generally means that the actual value is within plus or minus 10%, 5%, 1%, or 0.5% of a particular value or range.

[0035] The present application provides a thermally conductive and wave-absorbing material composition, comprising component A and component B, wherein component A comprises, by mass, 3.5 to 5 parts of silicone oil, 30 to 50 parts of graphene-modified spherical silicon carbide, 40 to 50 parts of thermally conductive filler, and 0.02 to 0.03 parts of a catalyst; and component B comprises, by mass, 3.5 to 5 parts of silicone oil, 30 to 50 parts of graphene-modified spherical silicon carbide, 40 to 50 parts of thermally conductive filler, and 0.01 to 0.02 parts of an inhibitor.

[0036] The thermally conductive and absorbing material composition provided in the present application has ultra-high thermal conductivity, a thermal conductivity coefficient of 10~12 W / (m·K), a hardness of 65±5 Shore OO after curing, and has efficient wave absorbing performance, which can effectively suppress electromagnetic problems in the 0.1~8GHz frequency band in communication equipment; silicon carbide and graphene are both highly thermally conductive materials and have wave absorbing effects. In particular, after silicon carbide is modified with graphene, its application in products can significantly improve dielectric loss, thereby helping to reduce the proportion of magnetic absorbers with poor thermal conductivity in product design, and improving the thermal conductivity of the product; the specific surface area of ​​the graphene-modified spherical silicon carbide in the raw materials of the thermally conductive and absorbing material composition is less than 1 m 2 / g, has good filling performance, which is conducive to the realization of ultra-high thermal conductivity.

[0037] The present application is further described below with reference to the following examples. The scope of protection of the present application is not limited by the following examples.

[0038] Example 1

[0039] This embodiment provides a thermal conductive and wave absorbing material composition, including component A and component B, wherein component A includes, by mass, 4.5 parts of vinyl silicone oil, 24.9 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 70 μm, 7.1 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 20 μm, 18 parts of iron-based amorphous alloy powder, 36 parts of aluminum nitride powder with a particle size (D50) of approximately 96, 9.5 parts of zinc oxide powder with a particle size (D50) of approximately 1 μm, and 0.025 parts of catalytic agent; the component B includes, by mass, 4.1 parts of vinyl silicone oil, 0.4 parts of hydrogenated silicone oil, 24.9 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 70 μm, 7.1 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 20 μm, 18 parts of iron-based amorphous alloy powder, 36 parts of aluminum nitride powder with a particle size (D50) of approximately 96, 9.5 parts of zinc oxide powder with a particle size (D50) of approximately 1 μm and 0.02 parts of an inhibitor; the volume ratio of component A to component B is 1:1.

[0040] The preparation method of the thermal conductive wave absorbing material includes:

[0041] Spherical silicon carbide powder was prepared by spray granulation. After screening, spherical silicon carbide powder with a particle size (D50) of approximately 70 μm and spherical silicon carbide powder with a particle size (D50) of approximately 20 μm were obtained. The spherical silicon carbide powder was modified using a ball milling process. During the ball milling process, a graphene slurry in ethanol was added. The amount of graphene used was 0.1% by weight of the silicon carbide. After the ball milling, the graphene-modified spherical silicon carbide was dried.

[0042] 4.5 parts of vinyl silicone oil, 24.9 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 70 μm, 7.1 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 20 μm, 18 parts of iron-based amorphous alloy powder, 18 parts of iron-based amorphous alloy powder, 36 parts of aluminum nitride powder with a particle size (D50) of approximately 96, 9.5 parts of zinc oxide powder with a particle size (D50) of approximately 1 μm and 0.025 parts of a catalyst were mixed and stirred uniformly at room temperature, maintaining a vacuum of ≤10 Pa during the stirring process, and the stirring time was 30 min to obtain component A.

[0043] 4.1 parts of vinyl silicone oil, 0.4 parts of hydrogenated silicone oil, 24.9 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 70 μm, 7.1 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 20 μm, 18 parts of iron-based amorphous alloy powder, 36 parts of aluminum nitride powder with a particle size (D50) of approximately 96, 9.5 parts of zinc oxide powder with a particle size (D50) of approximately 1 μm and 0.02 parts of an inhibitor were mixed and stirred uniformly at room temperature, maintaining a vacuum of ≤10 Pa during the stirring process, and the stirring time was 30 min to obtain component B.

[0044] The component A and component B prepared above are mixed in a volume ratio of 1:1, and after curing, a heat conductive wave absorbing material is obtained.

[0045] The preparation flow chart of the thermal conductive and wave absorbing material is as follows: Figure 1 shown.

[0046] Example 2

[0047] This embodiment provides a thermal conductive and wave absorbing material composition, including component A and component B, wherein component A includes, by mass, 4.5 parts of vinyl silicone oil, 24.7 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 70 μm, 12.5 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 20 μm, 9.3 parts of iron-based amorphous alloy powder, 39 parts of aluminum nitride powder with a particle size (D50) of approximately 96, 10 parts of aluminum oxide powder with a particle size (D50) of approximately 1 μm, and 0.025 parts of catalytic agent; the component B includes, by mass, 4.1 parts of vinyl silicone oil, 0.4 parts of hydrogenated silicone oil, 24.7 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 70 μm, 12.5 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 20 μm, 9.3 parts of iron-based amorphous alloy powder, 39 parts of aluminum nitride powder with a particle size (D50) of approximately 96, 10 parts of zinc oxide powder with a particle size (D50) of approximately 1 μm and 0.02 parts of an inhibitor; the volume ratio of component A to component B is 1:1.

[0048] The preparation method of the thermal conductive wave absorbing material includes:

[0049] Spherical silicon carbide powder was prepared by spray granulation and sieved to obtain spherical silicon carbide powders with particle sizes (D50) of approximately 70 μm and approximately 20 μm. The spherical silicon carbide powder was modified using a ball milling process. During the ball milling process, a graphene slurry in ethanol was added, with the amount of graphene being 0.1% by weight of the silicon carbide. After the ball milling, the graphene-modified spherical silicon carbide was dried.

[0050] 4.5 parts of vinyl silicone oil, 24.7 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 70 μm, 12.5 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 20 μm, 9.3 parts of iron-based amorphous alloy powder, 39 parts of aluminum nitride powder with a particle size (D50) of approximately 96, 10 parts of zinc oxide powder with a particle size (D50) of approximately 1 μm and 0.025 parts of a catalyst were mixed and stirred uniformly at room temperature, maintaining a vacuum of ≤10 Pa during the stirring process, and the stirring time was 30 min to obtain component A.

[0051] 4.1 parts of vinyl silicone oil, 0.4 parts of hydrogenated silicone oil, 24.7 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 70 μm, 12.5 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 20 μm, 9.3 parts of iron-based amorphous alloy powder, 39 parts of aluminum nitride powder with a particle size (D50) of approximately 96, 10 parts of zinc oxide powder with a particle size (D50) of approximately 1 μm and 0.02 parts of an inhibitor were mixed and stirred uniformly at room temperature, maintaining a vacuum of ≤10 Pa during the stirring process, and the stirring time was 30 min to obtain component B.

[0052] The component A and component B prepared above are mixed in a volume ratio of 1:1, and after curing, a heat conductive wave absorbing material is obtained.

[0053] Example 3

[0054] This embodiment provides a thermal conductive and wave absorbing material composition, including component A and component B. Component A includes, by mass, 4.5 parts of vinyl silicone oil, 30 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 70 μm, 20 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 45 μm, 31 parts of aluminum nitride powder with a particle size (D50) of approximately 96 μm, 9 parts of aluminum oxide powder with a particle size (D50) of approximately 2.5 μm, 5.5 parts of zinc oxide powder with a particle size (D50) of approximately 1 μm, and 0.025 parts of a catalyst. ; The component B includes, by mass, 4.12 parts of vinyl silicone oil, 0.38 parts of hydrogenated silicone oil, 30 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 70 μm, 20 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of approximately 45 μm, 31 parts of aluminum nitride powder with a particle size (D50) of approximately 96, 9 parts of aluminum oxide powder with a particle size (D50) of approximately 2.5 μm, 5.5 parts of zinc oxide powder with a particle size (D50) of approximately 1 μm, and 0.02 parts of an inhibitor; the volume ratio of component A to component B is 1:1.

[0055] The preparation method of the thermal conductive wave absorbing material includes:

[0056] Spherical silicon carbide powder was prepared by spray granulation and sieved to obtain spherical silicon carbide powders with particle sizes (D50) of approximately 70 μm and 45 μm. The spherical silicon carbide powder was modified using a ball milling process. During the ball milling process, a graphene slurry in ethanol was added, with the amount of graphene being 0.1% by weight of the silicon carbide. After the ball milling, the graphene-modified spherical silicon carbide was dried.

[0057] 4.5 parts of vinyl silicone oil, 30 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of about 70 μm, 20 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of about 45 μm, 31 parts of aluminum nitride powder with a particle size (D50) of about 96, 9 parts of aluminum oxide powder with a particle size (D50) of about 2.5 μm, 5.5 parts of zinc oxide powder with a particle size (D50) of about 1 μm and 0.025 parts of a catalyst were mixed and stirred uniformly at room temperature, maintaining a vacuum of ≤10 Pa during the stirring process, and the stirring time was 30 min to prepare component A.

[0058] 4.12 parts of vinyl silicone oil, 0.38 parts of hydrogenated silicone oil, 30 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of about 70 μm, 20 parts of graphene-modified spherical silicon carbide powder with a particle size (D50) of about 45 μm, 31 parts of aluminum nitride powder with a particle size (D50) of about 96, 9 parts of aluminum oxide powder with a particle size (D50) of about 2.5 μm, 5.5 parts of zinc oxide powder with a particle size (D50) of about 1 μm and 0.02 parts of an inhibitor were mixed and stirred uniformly at room temperature, maintaining a vacuum of ≤10 Pa during the stirring process, and the stirring time was 30 min to prepare component B.

[0059] The component A and component B prepared above are mixed in a volume ratio of 1:1, and after curing, a heat conductive wave absorbing material is obtained.

[0060] Comparative Example 1

[0061] This comparative example provides a heat-conducting and wave-absorbing material composition, which differs from Example 1 in that the graphene-modified spherical silicon carbide is replaced with graphene-modified micron-sized amorphous silicon carbide;

[0062] The difference between the preparation method of the graphene-modified micron-sized amorphous silicon carbide and the preparation method of the graphene-modified spherical silicon carbide powder in Example 1 is that the spherical silicon carbide with a particle size (D50) of about 70 μm and about 45 μm is replaced with amorphous silicon carbide with a particle size (D50) of about 70 μm and about 45 μm.

[0063] 4.5 parts of vinyl silicone oil, 20.3 parts and 6.7 parts of the aforementioned modified amorphous silicon carbide powder with a particle size (D50) of approximately 70 μm and approximately 45 μm, respectively, 26 parts of iron-based amorphous alloy powder, 34 parts of aluminum nitride powder with a particle size (D50) of approximately 96 μm, 8.5 parts of zinc oxide powder with a particle size (D50) of approximately 1 μm, and 0.025 parts of a catalyst were mixed and stirred uniformly at room temperature, maintaining a vacuum of ≤10 Pa during the stirring process, and the stirring time was 30 min to obtain component A.

[0064] 4.1 parts of vinyl silicone oil, 0.4 parts of hydrogenated silicone oil, 20.3 parts and 6.7 parts of the aforementioned modified amorphous silicon carbide powder with a particle size (D50) of approximately 70 μm and approximately 20 μm, respectively, 26 parts of iron-based amorphous alloy powder, 34 parts of aluminum nitride powder with a particle size (D50) of approximately 96, 8.5 parts of zinc oxide powder with a particle size (D50) of approximately 1 μm, and 0.02 parts of an inhibitor were mixed and stirred uniformly at room temperature, maintaining a vacuum of ≤10 Pa during the stirring process, and the stirring time was 30 min to obtain component B.

[0065] The component A and component B prepared above are mixed in a volume ratio of 1:1, and after curing, a heat conductive wave absorbing material is obtained.

[0066] The thermal conductive wave absorbing material provided in this application was applied to a test fixture (simulating a communication device) with a thickness of about 0.7 mm. After assembly, the S21 of 0.1 to 8 GHz was tested. The same test was performed without the thermal conductive wave absorbing material as a blank control. The application test effect diagrams of Examples 1 to 3 are shown as follows: Figure 2 、 Figure 3 、 Figure 4 As shown, the application test effect diagram of comparative example 1 is as follows Figure 5 As shown; the results show that the thermal conductive and absorbing material provided in this application can not only provide ultra-high thermal conductivity (thermal conductivity coefficient ≥10 W / (m·K)), but also effectively solve the electromagnetic problems in the 0.1~8 GHz frequency band in the equipment at a relatively thin application thickness of 0.7 mm.

[0067] The performance of the thermal conductive and wave absorbing materials provided in Examples 1-3 and Comparative Example 1 was tested using the following method:

[0068] Thermal conductivity: Tested according to the method standard ISO 22007-2:2008;

[0069] Hardness: Shore OO durometer, 3s reading.

[0070] The test results are shown in Table 1.

[0071] Table 1

[0072]

[0073] As shown in Table 1, the thermal conductivity of the heat-conducting and absorbing material of the present application can reach above 10 W / (m·K), and the hardness is between 63 and 65. Example 3 does not add an iron-based absorber. While meeting the absorbing performance requirements, the thermal conductivity is significantly improved to 12.057 W / (m·K). Comparative Example 1, while also meeting the absorbing performance application requirements, has a thermal conductivity of <10 W / (m·K).

[0074] The above is only a preferred specific implementation method of the present application, but the scope of protection of the present application is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes based on the technical solution and application concept of the present application within the technical scope disclosed in the present application, and they should be covered by the scope of protection of the present application.

Claims

1. A thermal conductive and wave absorbing material composition, characterized in that: The invention comprises component A and component B, wherein component A comprises, in parts by mass, 3.5 to 5 parts of silicone oil, 30 to 50 parts of graphene-modified spherical silicon carbide, 40 to 50 parts of thermally conductive filler and 0.02 to 0.03 parts of catalyst; and component B comprises, in parts by mass, 3.5 to 5 parts of silicone oil, 30 to 50 parts of graphene-modified spherical silicon carbide, 40 to 50 parts of thermally conductive filler and 0.01 to 0.02 parts of inhibitor.

2. The thermal conductive and wave absorbing material composition according to claim 1, characterized in that: The specific surface area of ​​the graphene-modified spherical silicon carbide in component A and component B is independently 0.2 m 2 / g to 1 m 2 / g.

3. The thermal conductive and wave absorbing material composition according to claim 1, wherein: The mass ratio of graphene to spherical silicon carbide in the graphene-modified spherical silicon carbide in component A and component B is independently (0.05-1): (95-100); and the particle size of the spherical silicon carbide is independently 10 μm to 100 μm.

4. The thermal conductive and wave absorbing material composition according to claim 1, wherein: The spherical silicon carbide in the graphene-modified spherical silicon carbide in component A and component B independently includes large-particle spherical silicon carbide and / or small-particle spherical silicon carbide; the particle size of the large-particle spherical silicon carbide is 70 μm, and the particle size of the small-particle spherical silicon carbide is 20 μm.

5. The thermal conductive and wave absorbing material composition according to claim 1, wherein: The thickness of the graphene in the graphene-modified spherical silicon carbide in component A and component B is independently 1 nm to 4 nm; the sheet diameter of the graphene is independently 1 μm to 5 μm; the specific surface area of ​​the graphene is independently 50 m 2 / g to 85m 2 / g.

6. The thermal conductive and wave absorbing material composition according to claim 1, wherein: The silicone oil in component A and component B independently comprises vinyl silicone oil and / or hydrogen-containing silicone oil; the thermally conductive filler in component A and component B independently comprises one or more of aluminum oxide, aluminum nitride, boron nitride or zinc oxide; the particle size of the thermally conductive filler in component A and component B independently ranges from 1 μm to 96 μm; and the volume ratio of component A to component B is (0.8-1.2):

1.

7. The thermal conductive and wave absorbing material composition according to claim 1, wherein: The catalyst in component A includes a platinum catalyst; the inhibitor in component B includes one or more of methyltris(1,1-dimethyl-1-ethynylmethoxy)silane, vinyltris(1,1-dimethyl-1-ethynylmethoxy)silane, phenyltris(1,1-dimethyl-1-ethynylmethoxy)silane, 3-methyl-1-butyn-3-ol, 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, N,N,N',N'-tetraallyl terephthalamide or monoallyl maleate.

8. The thermal conductive and wave absorbing material composition according to claim 1, wherein: The component A and the component B independently further comprise 9 to 18 parts of an iron-based absorbent in parts by mass; the iron-based absorbent comprises an iron-based amorphous alloy powder; and the particle size of the iron-based absorbent is 1 μm to 10 μm.

9. A method for preparing the thermal conductive and wave absorbing material according to any one of claims 1 to 8, characterized in that: include: Mixing graphene-modified spherical silicon carbide, a thermally conductive filler, silicone oil, and a catalyst to obtain component A; Mixing graphene-modified spherical silicon carbide, a thermally conductive filler, silicone oil, and an inhibitor to obtain component B; Component A and component B are mixed and cured to obtain a heat-conducting and wave-absorbing material.

10. The preparation method according to claim 9, characterized in that The preparation methods of the graphene-modified spherical silicon carbide each independently include: mixing spherical silicon carbide and graphene, and ball milling to obtain the graphene-modified spherical silicon carbide.

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