阅读说明：本技术 一种导热吸波硅脂及其制备方法 (Heat-conducting wave-absorbing silicone grease and preparation method thereof ) 是由 李静 王喆 张贵恩 范晋锋 李炳章 于 2021-07-21 设计创作，主要内容包括：本发明涉及导热吸波材料的制备技术领域,提供了一种导热吸波硅脂及其制备方法,导热吸波硅脂材料包括以下重量份数的组份：基础硅油50～100份、导热填料200～500份、吸波填料600～1000份、表面改性剂及助剂20～50份,通过将导热填料、吸波填料在高温真空下充分搅拌,后将其他组份用相同方法进行处理,既保证了导热填料与吸波填料的均匀分布,又保证了填料与基体之间的界面相容性,从而提高导热吸波硅脂的导热、吸波功能。该类产品主要应用于CPU等高功率部件内部微空隙及不规则孔洞,解决热管理、吸波双功能兼容的问题。(The invention relates to the technical field of preparation of heat-conducting wave-absorbing materials, and provides heat-conducting wave-absorbing silicone grease and a preparation method thereof, wherein the heat-conducting wave-absorbing silicone grease material comprises the following components in parts by weight: 50-100 parts of basic silicone oil, 200-500 parts of heat-conducting filler, 600-1000 parts of wave-absorbing filler and 20-50 parts of surface modifier and auxiliary agent, wherein the heat-conducting filler and the wave-absorbing filler are fully stirred under high-temperature vacuum, and then other components are treated by the same method, so that the uniform distribution of the heat-conducting filler and the wave-absorbing filler is ensured, the interface compatibility between the filler and a matrix is also ensured, and the heat-conducting and wave-absorbing functions of the heat-conducting wave-absorbing silicone grease are improved. The product is mainly applied to micro-gaps and irregular holes inside high-power components such as a CPU (central processing unit) and the like, and solves the problem of compatibility of heat management and wave absorption.)

1. The heat-conducting wave-absorbing silicone grease is characterized by comprising the following components in parts by weight:

50-100 parts of base silicone oil, 200-500 parts of heat-conducting filler, 600-1000 parts of wave-absorbing filler and 20-50 parts of surface modifier and auxiliary agent;

the basic silicone oil is linear silicone oil, the viscosity at 25 ℃ is 100-1500 mPa & s, and the structural formula is as follows:

wherein m is polymerization degree, R is inactive alkyl, R groups can be same or different, and m is a natural number larger than 1.

2. The heat-conducting wave-absorbing silicone grease as claimed in claim 1, wherein the heat-conducting filler is one or more of aluminum oxide, zinc oxide, silicon oxide, calcium oxide, magnesium oxide, boron nitride and aluminum nitride.

3. The heat-conducting wave-absorbing silicone grease as claimed in claim 1, wherein the average particle size of the heat-conducting filler is 30-70 μm, and the structure is spherical, spheroidal or flaky.

4. The heat-conducting wave-absorbing silicone grease as claimed in claim 1, wherein the wave-absorbing filler is one or two of carbonyl iron, sendust, iron powder, graphite powder, ferrite and silicon carbide.

5. The heat-conducting wave-absorbing silicone grease as claimed in claim 1 or 4, wherein the wave-absorbing filler has an average particle size of 5-50 μm and a spherical, spheroidal or sheet structure.

6. The heat-conducting wave-absorbing silicone grease as claimed in claim 1, wherein in the compounding process of the heat-conducting filler and the wave-absorbing filler, the average particle size of the wave-absorbing filler is 5-30 μm, the average particle size of the heat-conducting filler is 50-70 μm, and the heat-conducting filler and the wave-absorbing filler are mixed to form the bifunctional powder with the average particle size of 30-50 μm.

7. The heat-conducting wave-absorbing silicone grease as claimed in claim 1, wherein the surface modifier is one of a silane coupling agent, an aluminate coupling agent or a titanate coupling agent, the silane coupling agent is one of methylmethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 3-aminopropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane or 3-glycidoxypropyltrimethoxysilane, and the aluminate coupling agent is one of LK-AL18 and LK-AL181 aluminate coupling agent; the titanate coupling agent is one of LK-002, LK-105, LK-300 and LK-401 titanate coupling agents.

8. The heat-conducting wave-absorbing silicone grease as claimed in claim 1, wherein the auxiliary agent is an anti-settling agent and an antioxidant, the anti-settling agent is one of fumed silica, bentonite or polyamide wax, and the antioxidant is one of antioxidant 1010 or antioxidant CA.

9. A preparation method of heat-conducting wave-absorbing silicone grease is characterized by comprising the following steps:

s1, weighing the following raw materials in parts by weight: 50-100 parts of base silicone oil, 200-500 parts of heat-conducting filler, 600-1000 parts of wave-absorbing filler and 20-50 parts of surface modifier and auxiliary agent;

s2, stirring the heat-conducting filler, the wave-absorbing filler and the surface modifier weighed in the S1 under the conditions that the vacuum degree is-0.080 MPa to-0.130 MPa, the mixing temperature is 80 to 150 ℃, and the stirring speed is 80 to 130rpm, so that the materials are mixed into uniform powder;

s3, mixing the basic silicone oil and the auxiliary agent weighed in the S1 under the conditions that the vacuum degree is-0.080 MPa to-0.130 MPa, the mixing temperature is 50 ℃ to 100 ℃, and the stirring speed is 100 rpm to 160rpm to obtain uniform flowing liquid;

s4, adding the mixed powder in the S2 into the S3 fluid liquid, and continuously stirring the mixture until the mixture is uniform under the conditions that the vacuum degree is-0.080 MPa to-0.130 MPa, the mixing temperature is 80 to 150 ℃ and the stirring speed is 80 to 130rpm, thereby finally obtaining the heat-conducting wave-absorbing silicone grease.

Technical Field

The invention relates to the technical field of preparation of heat-conducting wave-absorbing materials, in particular to heat-conducting wave-absorbing silicone grease and a preparation method thereof.

Background

With the rapid development of high integration, miniaturization, multi-functionalization and high performance of 5G and electronic device equipment, the importance of materials required for electronic equipment to cope with high frequency environments is continuously increasing. For the development of electronic devices, it is a problem to enhance heat conduction and suppress electromagnetic wave conduction, which is a problem to be faced by the product manufacturing end.

At present, the gasket products with double functions of heat conduction and wave absorption appear in the market, and can be directly attached to an integrated circuit, a radiating fin or other heat conduction equipment, so that the problems of electromagnetic compatibility and heat management are solved. However, no heat-conducting wave-absorbing silicone grease product is reported at present, and the product is mainly applied to micro-gaps and irregular holes inside high-power components such as a CPU (central processing unit) and the like, so that the problem of compatibility of double functions of heat management and wave absorption is solved.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides the heat conduction wave absorption silicone grease and the preparation method thereof, and the prepared heat conduction wave absorption silicone grease has the characteristics of high heat conductivity coefficient, stable electromagnetic wave absorption capacity and strong liquidity. The technical scheme adopted by the invention is as follows:

a heat-conducting wave-absorbing silicone grease comprises the following components in parts by weight:

50-100 parts of base silicone oil, 200-500 parts of heat-conducting filler, 600-1000 parts of wave-absorbing filler and 20-50 parts of surface modifier and auxiliary agent;

preferably, the base silicone oil is linear silicone oil, the viscosity at 25 ℃ is 100-1500 mPa & s, and the structural formula is as follows:

wherein m is polymerization degree, R is inactive alkyl, such as methyl, ethyl, propyl and isomers thereof, R groups can be the same or different, and m is a natural number larger than 1.

Preferably, the heat-conducting filler is formed by compounding one or more of aluminum oxide, zinc oxide, silicon oxide, calcium oxide, magnesium oxide, boron nitride and aluminum nitride, the average grain diameter of the heat-conducting filler is 30-70 mu m, and the structure of the heat-conducting filler is spherical, spheroidal or flaky.

Preferably, the wave-absorbing filler is one or two of carbonyl iron, iron-silicon-aluminum, iron powder, graphite powder, ferrite and silicon carbide, and is compounded, the average particle size of the wave-absorbing filler is 5-50 mu m, and the structure of the wave-absorbing filler is spherical, spheroidal or flaky.

Preferably, in the compounding process of the heat-conducting filler and the wave-absorbing filler, the average grain size of the wave-absorbing filler is 5-30 μm, the average grain size of the heat-conducting filler is 50-70 μm, and the heat-conducting filler and the wave-absorbing filler are mixed to form the bifunctional powder with the average grain size of 30-50 μm.

Preferably, the surface modifier is one of a silane coupling agent, an aluminate coupling agent or a titanate coupling agent, and the silane coupling agent is one of methyl methoxysilane, methyl triethoxysilane, vinyl trimethoxysilane, vinyl triethoxysilane, 3-aminopropyltriethoxysilane, 3-methacryloxypropyl trimethoxysilane or 3-glycidoxypropyltrimethoxysilane; the aluminate coupling agent is one of LK-AL18 and LK-AL181 aluminate coupling agents; the titanate coupling agent is one of LK-002, LK-105, LK-300 and LK-401 titanate coupling agents.

Preferably, the auxiliary agent is an anti-settling agent and an antioxidant, the anti-settling agent is one of fumed silica, bentonite or polyamide wax, and the antioxidant is one of antioxidant 1010 or antioxidant CA.

A preparation method of heat-conducting wave-absorbing silicone grease comprises the following steps:

s1, weighing the following raw materials in parts by weight: 50-100 parts of base silicone oil, 200-500 parts of heat-conducting filler, 600-1000 parts of wave-absorbing filler and 20-50 parts of surface modifier and auxiliary agent;

s2, stirring the heat-conducting filler, the wave-absorbing filler and the surface modifier weighed in the S1 under the conditions that the vacuum degree is-0.080 MPa to-0.130 MPa, the mixing temperature is 80 to 150 ℃, and the stirring speed is 80 to 130rpm, so that the materials are mixed into uniform powder;

s3, mixing the basic silicone oil and the auxiliary agent weighed in the S1 under the conditions that the vacuum degree is-0.080 MPa to-0.130 MPa, the mixing temperature is 50 ℃ to 100 ℃, and the stirring speed is 100 rpm to 160rpm to obtain uniform flowing liquid;

s4, adding the mixed powder in the S2 into the S3 fluid liquid, and continuously stirring the mixture until the mixture is uniform under the conditions that the vacuum degree is-0.080 MPa to-0.130 MPa, the mixing temperature is 80 to 150 ℃ and the stirring speed is 80 to 130rpm, thereby finally obtaining the heat-conducting wave-absorbing silicone grease.

Compared with the prior art, the invention has the beneficial effects that:

the heat-conducting wave-absorbing silicone grease is prepared by taking the basic silicone oil, the heat-conducting filler, the wave-absorbing filler surface modifier and the auxiliary agent as raw materials, the heat-conducting filler and the wave-absorbing filler are subjected to granularity matching, the heat-conducting and wave-absorbing double functions of the heat-conducting wave-absorbing silicone grease are effectively improved, the heat conductivity coefficient reaches 2.9W/m.K, and the reflectivity is less than or equal to-10 dB in the frequency range of 8-18 GHz.

Drawings

FIG. 1 is a schematic diagram of the internal structure of a heat-conducting wave-absorbing silicone grease product;

FIG. 2 is a linear fitting curve of thermal resistance-thickness of heat-conducting wave-absorbing silicone grease;

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1:

the embodiment provides heat-conducting wave-absorbing silicone grease which comprises the following components in parts by weight:

50g of basic silicone oil, 260g of heat conducting filler, 700g of wave absorbing filler, 20g of surface modifier, 5g of anti-settling agent and 3g of antioxidant;

wherein the base silicone oil isI.e. R ═ CH₃，m＝30；

The heat conducting filler consists of 210g of alumina with the average particle size of 50-70 mu m and 50g of aluminum nitride with the average particle size of 40-50 mu m;

the wave-absorbing filler consists of 350g of carbonyl iron with the average particle size of 10-30 mu m and 350g of ferrum-silicon-aluminum with the average particle size of 30-40 mu m;

the surface modifier is vinyl trimethoxy silane;

the anti-settling agent is fumed silica;

the antioxidant is antioxidant 1010;

the preparation method of the heat-conducting wave-absorbing silicone grease comprises the following steps:

s1, weighing the following raw materials, by weight, 50g of basic silicone oil, 260g of heat conducting filler, 700g of wave absorbing filler, 20g of surface modifier, 5g of anti-settling agent and 3g of antioxidant;

s2, placing the heat-conducting filler, the wave-absorbing filler and the surface modifier weighed in the step S1 into a double-planet stirrer, and mixing the materials uniformly under the conditions that the vacuum degree is-0.085 MPa, the temperature is 90 ℃ and the rotating speed is 120 rpm;

s3, placing the basic silicone oil and the auxiliary agent weighed in the S1 into a double-planet stirrer, and stirring to obtain uniform liquid under the conditions that the vacuum degree is-0.095 MPa, the temperature is 50 ℃ and the rotating speed is 150 rpm;

s4, adding the S2 uniformly mixed powder into the uniform liquid obtained in the S3, and mixing under the conditions that the vacuum degree is-0.098 MPa, the temperature is 90 ℃ and the rotating speed is 120rpm to obtain the heat-conducting wave-absorbing silicone grease.

Through tests, the heat conductivity coefficient of the heat-conducting wave-absorbing silicone grease is 2.8W/m.K, and the reflectivity in the frequency range of 8-18 GHz is less than or equal to-10 dB.

Example 2:

the embodiment provides heat-conducting wave-absorbing silicone grease which comprises the following components in parts by weight:

50g of basic silicone oil, 265g of heat conducting filler, 700g of wave absorbing filler, 20g of surface modifier, 7g of anti-settling agent and 3g of antioxidant;

wherein the base silicone oil isI.e., R ═ Et, m ═ 25;

the heat conducting filler consists of 200g of alumina with the average grain diameter of 60-70 mu m and 65g of boron nitride with the average grain diameter of 40-50 mu m;

the wave-absorbing filler consists of 350g of carbonyl iron with the average particle size of 10-30 mu m and 350g of ferrum-silicon-aluminum with the average particle size of 30-40 mu m;

the surface modifier is vinyl triethoxysilane;

the anti-settling agent is bentonite;

the antioxidant is antioxidant 1010;

the preparation method of the heat-conducting wave-absorbing silicone grease comprises the following steps:

s1, weighing the following components in parts by weight, 700g of wave-absorbing filler, 20g of surface modifier, 7g of anti-settling agent and 3g of antioxidant;

s2, placing the heat-conducting filler, the wave-absorbing filler and the surface modifier weighed in the S1 into a double-planet stirrer, and mixing the materials uniformly under the conditions that the vacuum degree is-0.095 MPa, the temperature is 100 ℃ and the rotating speed is 120 rpm;

s3, placing the basic silicone oil and the auxiliary agent weighed in the S1 into a double-planet stirrer, and stirring to obtain uniform liquid under the conditions that the vacuum degree is-0.095 MPa, the temperature is 50 ℃ and the rotating speed is 150 rpm;

s4, adding the S2 uniformly mixed powder into S3, and mixing at 90 ℃ and 120rpm under the vacuum degree of-0.095 MPa to obtain the heat-conducting wave-absorbing silicone grease.

Through tests, the heat conductivity coefficient of the heat-conducting wave-absorbing silicone grease is 2.9W/m.K, and the reflectivity in the frequency range of 8-18 GHz is less than or equal to-10 dB.

Example 3:

the embodiment provides heat-conducting wave-absorbing silicone grease which comprises the following components in parts by weight:

50g of basic silicone oil, 260g of heat conducting filler, 705g of wave absorbing filler, 20g of surface modifier, 5g of anti-settling agent and 3g of antioxidant;

wherein the base silicone oil isNamely, R ═ CH3, m ═ 30;

the heat conducting filler consists of 200g of alumina with the average grain diameter of 60-70 mu m and 60g of boron nitride with the average grain diameter of 40-50 mu m;

the wave-absorbing filler consists of 355g of ferrite with the average grain diameter of 10-30 mu m and 350g of sendust with the average grain diameter of 30-40 mu m;

the surface modifier is 3-aminopropyl triethoxysilane;

the anti-settling agent is bentonite;

the antioxidant is antioxidant CA;

the preparation method of the heat-conducting wave-absorbing silicone grease comprises the following steps:

s1, weighing the following raw materials, by weight, 50g of basic silicone oil, 260g of heat conducting filler, 705g of wave absorbing filler, 20g of surface modifier, 5g of anti-settling agent and 3g of antioxidant;

s2, placing the heat-conducting filler, the wave-absorbing filler and the surface modifier weighed in the S1 into a double-planet stirrer, and mixing the materials uniformly under the conditions that the vacuum degree is-0.095 MPa, the temperature is 100 ℃ and the rotating speed is 120 rpm;

s3, placing the basic silicone oil and the auxiliary agent weighed in the S1 into a double-planet stirrer, and stirring to obtain uniform liquid under the conditions that the vacuum degree is-0.095 MPa, the temperature is 50 ℃ and the rotating speed is 150 rpm;

s4, adding the S2 uniformly mixed powder into S3, and mixing at 90 ℃ and 120rpm under the vacuum degree of-0.095 MPa to obtain the heat-conducting wave-absorbing silicone grease.

Through tests, the heat conductivity coefficient of the heat-conducting wave-absorbing silicone grease is 2.8W/m.K, and the reflectivity in the frequency range of 8-18 GHz is less than or equal to-10 dB.

Comparative example 1: the comparative example 1 explores the influence of the heat-conducting filler and the wave-absorbing filler with similar particle sizes on the heat conductivity coefficient of the product.

The comparative example provides heat-conducting wave-absorbing silicone grease which comprises the following components in parts by weight:

50g of basic silicone oil, 260g of heat conducting filler, 700g of wave absorbing filler, 20g of surface modifier, 5g of anti-settling agent and 3g of antioxidant;

wherein the base silicone oil isNamely, R ═ CH3, m ═ 30;

the heat conducting filler consists of 210g of alumina with the average grain diameter of 10-30 mu m and 50g of aluminum nitride with the average grain diameter of 20-40 mu m;

the wave-absorbing filler consists of 350g of carbonyl iron with the average particle size of 10-30 mu m and 350g of ferrum-silicon-aluminum with the average particle size of 30-40 mu m;

the surface modifier is vinyl trimethoxy silane;

the anti-settling agent is fumed silica;

the antioxidant is antioxidant 1010;

the preparation method of the heat-conducting wave-absorbing silicone grease comprises the following steps:

s1, weighing the following raw materials, by weight, 50g of basic silicone oil, 260g of heat conducting filler, 700g of wave absorbing filler, 20g of surface modifier, 5g of anti-settling agent and 3g of antioxidant;

s2, placing the heat-conducting filler, the wave-absorbing filler and the surface modifier weighed in the step S1 into a double-planet stirrer, and mixing the materials uniformly under the conditions that the vacuum degree is-0.085 MPa, the temperature is 90 ℃ and the rotating speed is 120 rpm;

s3, placing the basic silicone oil and the auxiliary agent weighed in the S1 into a double-planet stirrer, and stirring to obtain uniform liquid under the conditions that the vacuum degree is-0.095 MPa, the temperature is 50 ℃ and the rotating speed is 150 rpm;

s4, adding the S2 uniformly mixed powder into S3, and mixing at 90 ℃ and 120rpm under the vacuum degree of-0.098 MPa to obtain the heat-conducting wave-absorbing silicone grease.

Through tests, the heat conductivity coefficient of the heat-conducting wave-absorbing silicone grease is 2.3W/m.K, and the reflectivity in the frequency range of 8-18 GHz is less than or equal to-10 dB.

By comparing the properties of the heat-conducting wave-absorbing silicone grease obtained in the comparative example 1 and the examples 1 to 3, the heat-conducting property of the heat-conducting wave-absorbing silicone grease can be improved by performing granularity matching on the heat-conducting filler and the wave-absorbing filler.

Comparative example 2: comparative example 2 investigates the effect of mixing at room temperature on the heat conductivity and wave absorption properties of the product;

the comparative example provides heat-conducting wave-absorbing silicone grease which comprises the following components in parts by weight:

50g of basic silicone oil, 265g of heat conducting filler, 700g of wave absorbing filler, 20g of surface modifier, 5g of anti-settling agent and 3g of antioxidant;

wherein the base silicone oil isI.e., R ═ CH3, m ═ 25;

the heat conducting filler consists of 200g of alumina with the average grain diameter of 60-70 mu m and 65g of boron nitride with the average grain diameter of 40-50 mu m;

the wave-absorbing filler consists of 350g of carbonyl iron with the average particle size of 10-30 mu m and 350g of ferrum-silicon-aluminum with the average particle size of 30-40 mu m;

the surface modifier is vinyl triethoxysilane;

the anti-settling agent is bentonite;

the antioxidant is antioxidant 1010;

the preparation method of the heat-conducting wave-absorbing silicone grease comprises the following steps:

s1, weighing the following raw materials, by weight, 50g of base silicone oil, 265g of heat conducting filler, 700g of wave absorbing filler, 20g of surface modifier, 5g of anti-settling agent and 3g of antioxidant;

s2, placing the heat-conducting filler, the wave-absorbing filler and the surface modifier weighed in the step S1 into a double-planet stirrer, and mixing the materials uniformly at normal temperature under the conditions that the vacuum degree is-0.095 MPa and the rotating speed is 120 rpm;

s3, placing the basic silicone oil and the auxiliary agent weighed in the S1 into a double-planet stirrer, and stirring at normal temperature to obtain uniform liquid, wherein the vacuum degree is-0.095 MPa and the rotating speed is 150 rpm;

s4, adding the S2 uniformly mixed powder into S3, and mixing at normal temperature under the vacuum degree of-0.095 MPa and the rotating speed of 120rpm to obtain the heat-conducting wave-absorbing silicone grease;

through tests, the heat conductivity coefficient of the heat-conducting wave-absorbing silicone grease is 2.3W/m.K, and the reflectivity in the frequency range of 8-18 GHz is less than or equal to-7 dB.

By comparing the performances of the heat-conducting wave-absorbing silicone grease obtained in the comparative example 2 and the examples 1 to 3, the performances of the heat-conducting wave-absorbing silicone grease obtained in the processes of S2, S3 and S4, namely mixing the heat-conducting filler/wave-absorbing filler/surface modifier, the basic silicone oil/auxiliary agent and the mixed powder/fluid liquid at high temperature, can be obtained, which is beneficial to improving the interface fusion of the filler and the matrix, and further improves the heat-conducting performance and the wave-absorbing performance of the heat-conducting wave-absorbing silicone grease.

Although only the preferred embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention within the knowledge of those skilled in the art, and all changes are encompassed in the scope of the present invention.