WO2017041454A1

WO2017041454A1 - High thermal conductivity composite interface material and preparation method therefor

Info

Publication number: WO2017041454A1
Application number: PCT/CN2016/074689
Authority: WO
Inventors: 彭典明; 刘伟德; 郑华伟; 郑金桥; 张航; 汪磊; 刘欣; 焦兰
Original assignee: 中兴通讯股份有限公司
Priority date: 2015-09-09
Filing date: 2016-02-26
Publication date: 2017-03-16
Also published as: CN106519700A

Abstract

Provided is a high thermal conductivity composite interface material, comprising an organosilicon polymer, a thermal conductivity powder and an adjuvant, wherein the thermal conductivity powder comprises a spherical thermal conductivity powder and a polyhedral thermal conductivity powder, and wherein the ratio in parts by weight of the organosilicon polymer, the spherical thermal conductivity powder, the polyhedral thermal conductivity powder and the adjuvant is as follows: 5-10 of the organosilicon polymer, 75-90 of the spherical thermal conductivity powder, 1-5 of the polyhedral thermal conductivity powder, and 0.5-1 of the adjuvant. Also provided is a method for preparing a polyhedral high thermal conductivity composite interface material. The high thermal conductivity composite interface material is prepared by mixing and calendering an organosilicon polymer, a thermal conductivity powder and an adjuvant, wherein the thermal conductivity powder comprises a spherical thermal conductivity powder and a polyhedral thermal conductivity powder. By utilizing the polyhedral thermal conductivity powder to increase the contact surfaces of various materials, thereby increasing thermal conductivity channels, the thermal conductivity of the high thermal conductivity composite interface material prepared is up to 5.0-7.2 W/m•K.

Description

High thermal conductivity composite interface material and preparation method thereof

Technical field

The present application belongs to the field of thermal interface materials and heat dissipation technology of the electronic industry, and relates to a novel high thermal conductivity composite interface material, for example, a polyhedral thermal conductive composite interface material and a preparation method thereof.

Background technique

Heat dissipation has always been a key research work in the electronics industry. The actual operating temperature of electronic components is one of the key factors affecting its reliability. As electronic devices are moving toward miniaturization and high power consumption, their power density is gradually increasing. The heat generation of electronic equipment has also multiplied, which also puts higher requirements on the heat dissipation performance of the system.

The thermal interface material is the key material of the heat dissipation system and is the bridge connecting the heat transfer between the chip and the heat sink. According to the thermal conductive material filler and the production process, the thermal conductivity of the thermal interface material also shows a large difference. The main differences are: the choice of powder type, including shape and size; the choice of glue system, silicone, epoxy, acrylic, etc.; the choice of dispersing additives.

The materials of the thermally conductive filler which can be used as the thermal conductive interface material are: metal oxides such as Al2O3, ZnO, MgO, etc.; metal nitrides such as AlN, BN; graphite; ceramic powders and the like.

The production process of the thermal interface material mainly includes powder pretreatment, powder silica gel collective stirring and mixing, silica gel system vulcanization, and cutting and packaging. At present, the thermal conductivity of the large-scale thermal interface material is mostly below 5 W/m·K. Under the existing powder system and production process conditions, the thermal conductivity is difficult to be greatly improved.

Summary of the invention

The embodiments of the present invention provide a polyhedral high thermal conductive composite interface material and a preparation method thereof, and use a polyhedral thermal conductive powder to increase the contact surface of each material, thereby increasing the heat conduction channel and preparing the thermal conductivity. High high thermal conductivity composite interface material.

An embodiment of the present invention provides a high thermal conductive composite interface material, including a silicone polymer, a thermal conductive powder, and an auxiliary agent, wherein the thermal conductive powder comprises a spherical thermal conductive powder and a polyhedral thermal conductive powder.

The weight ratio of the spherical heat conductive powder and the polyhedral heat conductive powder is spherical heat conductive powder 75-90, and polyhedral heat conductive powder 1-5.

The weight ratio of the silicone polymer, the spherical heat conductive powder, the polyhedral heat conductive powder and the auxiliary agent may be 5-10 for the silicone polymer, 75-90 for the spherical heat conductive powder, and 1-5 for the polyhedron thermal conductive powder. Additive 0.5-1.

Wherein, the thermally conductive powder is one or more of alumina, aluminum nitride, zinc oxide and boron nitride.

The spherical thermally conductive powder may have a center particle diameter D50 of 0.2 to 100 μm.

The polyhedral thermally conductive powder may be a hexahedron to a dodecahedron, wherein the hexahedron is a combination of a regular triangular pyramid and a bottom surface of the inverted triangular vertebral body.

The polyhedral thermally conductive powder may also be a heptahedron to a dodecahedron.

The polyhedral thermally conductive powder may have a center particle diameter D50 of 0.2 to 1.0 μm.

Wherein, the silicone polymer is one or more of a vinyl polysiloxane, a phenenyl polysiloxane, a methacrylic acid siloxane, and a methyl vinyl polysiloxane.

The silicone polymer may have a gum viscosity of from 300 to 1000 mPa·s.

Wherein, the auxiliary agent comprises a coupling agent and a dispersing agent.

The coupling agent may be one or more of a silane coupling agent, a titanate coupling agent, and an aluminate coupling agent.

The dispersing agent may be polyethylene glycol.

Another aspect of the present invention provides a method for preparing a high thermal conductive composite interface material, including:

Mixing the silicone polymer, the thermal conductive powder and the auxiliary agent to obtain a mixture;

Performing a calendering treatment on the mixture to obtain the high thermal conductive composite interface material;

Wherein, the heat conductive powder comprises a spherical heat conductive powder and a polyhedral heat conductive powder.

Wherein, the mixing treatment of the silicone polymer, the heat conductive powder and the auxiliary agent comprises:

Drying the spherical thermal conductive powder and the polyhedral thermal conductive powder, and uniformly mixing with the silicone polymer to obtain a first mixture;

Adding an auxiliary agent to the first mixture, mixing uniformly, and then drying to obtain a second mixture;

The second mixture was subjected to vacuum stirring treatment to remove the gas therein to prepare a mixture.

The silicone polymer may have a gum viscosity of from 300 to 1000 mPa·s.

Wherein, the adding auxiliary agent is added to the first mixed material, and after uniformly mixing, drying treatment comprises:

Mixing the coupling agent with the dispersing agent, stirring uniformly, and preparing an auxiliary solution;

Adding the auxiliary solution to the first mixture, stirring uniformly, and preparing a second mixed preliminary material;

The second mixed preliminary material is subjected to a drying treatment to obtain a second mixed material.

Wherein, the auxiliary agent comprises a coupling agent and a dispersing agent.

The dispersing agent may be polyethylene glycol.

The processing temperature for drying the spherical heat conductive powder and the polyhedral heat conductive powder is 90-110 ° C, 20-60 min.

The spherical heat-conducting powder, the polyhedral heat-conducting powder and the silicone polymer may be mixed at a uniform stirring speed of 30-60 r/min, and the stirring time may be 20-60 min.

Mixing the auxiliary agent and the first mixture to obtain a stirring speed of the second mixed raw material may be 30-60r/min, the stirring time can be 20-60min.

The treatment temperature for drying the second mixed raw material may be 90-110 ° C, and the treatment time may be 20-60 min.

The stirring speed of the second mixture may be 30-120 r/min, the stirring time may be 20-60 min, and the processing temperature may be 80-130 °C.

The processing temperature of the calendering treatment may be 80 to 130 °C.

After the calendering treatment, a highly thermally conductive composite interface material having a thickness of 0.5 to 3 mm can be obtained.

The advantages and beneficial technical effects of the embodiments of the present invention are as follows:

1. The high thermal conductive composite interface material of the embodiment of the present invention uses a polyhedral thermal powder as a raw material, and uses a polyhedral thermal powder to increase the contact surface of each material to form a network structure capable of effectively increasing heat conduction, thereby increasing a heat conduction channel and making a thermal interface. The thermal conductivity of the material is greatly improved.

2. The high thermal conductive composite interface material of the embodiment of the invention is added with a coupling agent and a dispersing agent, and the silane coupling agent and the dispersing agent can improve the degree of infiltration of the powder in the silica gel system, increase the filling amount of the powder, and improve the dispersion of the powder. degree.

3. The high thermal conductive composite interface material of the embodiment of the invention has excellent performance and high thermal conductivity, and can reach 5.0-7.2 W/m·K.

4. The preparation method of the high thermal conductive composite interface material of the embodiment of the invention is simple in process, convenient in operation and easy to obtain raw materials, and is very suitable for large-scale industrial production.

BRIEF abstract

Figure 1 is an electron micrograph of a spherical heat conductive powder;

2 is a schematic view showing a thermal conduction contact model of a spherical heat conductive powder;

Figure 3 is an electron micrograph of a polyhedral thermal powder;

4 is a schematic view showing a heat conduction contact model containing a polyhedral heat conductive powder;

DESCRIPTION OF REFERENCE NUMERALS: 1. Silica gel matrix; 2. Spherical heat-conducting powder; 3. Polyhedral heat-conducting powder.

Embodiments of the invention

The invention will now be described with reference to the accompanying drawings and embodiments:

Example 1

1. Preparation of the first mixture

The spherical alumina powder, the spherical aluminum nitride powder and the polyhedral alumina powder are dried at 100 ° C for 30 min, and then cooled to room temperature;

8 g of methylvinylpolysiloxane, 85 g of dry spherical alumina and spherical aluminum nitride mixed powder (D50=1-70 μm, mass ratio of spherical alumina to spherical aluminum nitride of 7:3), A polyhedral alumina powder 3 g (D50 = 0.4 - 0.8 μm) was placed in a blender and stirred at a speed of 45 r/min for 30 min to prepare a first mixture.

2. Preparation of the second mixture

The silane coupling agent and the polyethylene glycol 200 were mixed and stirred uniformly to prepare a promoter solution having a concentration of 10 g/L; 0.8 g of the auxiliary solution was weighed and added to the first mixture, and stirred at a speed of 45 r/min. 40 min, the second mixture was prepared; the second mixture was dried at 100 ° C for 40 min, and cooled to room temperature to prepare a second mixture.

3. Preparation of the mixture

The second mixture was placed in a planetary mixer for vacuum agitation. The stirring speed of the planetary mixer was 80 r/min, the temperature was 100 ° C, and after stirring for 40 min, it was taken out to obtain a mixture.

4, calendering treatment

The obtained mixture was placed in a three-roll calender for calendering treatment, wherein the calendering temperature of the three-roll calender was controlled to be 100 ° C, the speed was 1.1 m / min, the thickness and the width were controlled, and the appropriate tension was adjusted to obtain a thickness of 2.5. Mm high thermal conductivity composite interface material.

The thermal conductivity of the high thermal conductive composite interface material was measured by a Ruiling LW9389 instrument, and the thermal conductivity was measured to be 5.0 W/m·K.

Example 2

1. Preparation of the first mixture

The phenenyl polysiloxane, the spherical zinc oxide powder, the spherical boron nitride powder, and the polyhedral aluminum nitride powder are dried at 90 ° C for 60 min, and then cooled to room temperature;

Weigh 6g of dry vinyl polysiloxane, 4g of phenenyl polysiloxane, 75g of mixed powder of spherical zinc oxide and spherical boron nitride (D50=0.2-50μm, quality of spherical zinc oxide and spherical boron nitride The ratio of 6:4), polyhedral aluminum nitride powder 5 g (D50 = 0.2-0.6 μm) was placed in a blender, and stirred at a speed of 60 r/min for 20 minutes to prepare a first mixture.

2. Preparation of the second mixture

The titanate coupling agent and the polyethylene glycol 400 were mixed and stirred uniformly to prepare a promoter solution having a concentration of 10 g/L; 1.0 g of the auxiliary solution was weighed and added to the first mixture at a rate of 30 r/min. The second mixture was prepared by stirring for 60 minutes; the second mixture was dried at 110 ° C for 20 minutes, and cooled to room temperature to prepare a second mixture.

3. Preparation of the mixture

The second mixture was placed in a planetary mixer for vacuum agitation. The stirring speed of the planetary mixer was 30 r/min, the temperature was 130 ° C, and after stirring for 60 minutes, it was taken out to obtain a mixture.

4, calendering treatment

The prepared mixture was placed in a three-roll calender for calendering treatment, wherein the rolling temperature of the three-roll calender was controlled to be 130 ° C, the speed was 1.4 m / min, the thickness and the width were controlled, and the appropriate tension was adjusted to obtain a thickness of 2.0. Mm high thermal conductivity composite interface material.

The thermal conductivity of the high thermal conductive composite interface material was measured by a Ruiling LW9389 instrument, and the thermal conductivity was measured to be 5.5 W/m·K.

Example 3

1. Preparation of the first mixture

The methacrylic acid siloxane, the spherical alumina powder, the spherical zinc oxide powder and the polyhedral boron nitride powder are dried at 110 ° C for 20 min, and then cooled to room temperature;

Weigh 3g of dry vinyl polysiloxane, 2g of methacrylic acid siloxane, 90g of mixed powder of spherical alumina and spherical zinc oxide (D50=3.0-100μm, mass ratio of spherical alumina and spherical zinc oxide 7:3), polyhedral boron nitride powder 1g (D50=0.4-1.0μm) was placed in a mixer at a rate of 30r/min The mixture was stirred for 60 minutes to prepare a first mixture.

2. Preparation of the second mixture

Mixing and stirring the aluminate coupling agent and polyethylene glycol 200 to obtain a concentration of 10g/L auxiliary solution, weigh 0.5g auxiliary solution and add it to the first mixture at 60r/min. The second mixture was prepared by stirring for 20 minutes; the second mixture was dried at 90 ° C for 60 minutes, and cooled to room temperature to prepare a second mixture.

3. Preparation of the mixture

The second mixture was placed in a planetary mixer for vacuum agitation. The stirring speed of the planetary mixer was 120 r/min, the temperature was 80 ° C, and after stirring for 20 minutes, it was taken out to obtain a mixture.

4, calendering treatment

The obtained mixture was placed in a three-roll calender for calendering treatment, wherein the calendering temperature of the three-roll calender was controlled to be 80 ° C, the speed was 0.8 m / min, the thickness and the width were controlled, and the appropriate tension was adjusted to obtain a thickness of 3.0. Mm high thermal conductivity composite interface material.

The thermal conductivity of the high thermal conductive composite interface material was measured by a Ruiling LW9389 instrument, and the thermal conductivity was measured to be 7.2 W/m·K.

Control case

1. Preparation of the first mixture

The spherical alumina powder and the spherical aluminum nitride powder were dried at 90 ° C for 30 min, and then cooled to room temperature;

Weigh 8 g of dry methylvinylpolysiloxane, 80 g of a mixed powder of spherical alumina and spherical aluminum nitride (D50=1-70 μm, mass ratio of spherical alumina to spherical aluminum nitride is 7:3), The mixture was placed in a blender and stirred at a speed of 45 r/min for 30 minutes to prepare a first mixture.

2. Preparation of the second mixture

The silane coupling agent and the polyethylene glycol 400 were mixed and stirred uniformly to prepare a promoter solution having a concentration of 10 g/L; 0.8 g of the auxiliary solution was weighed and added to the first mixture, and stirred at a speed of 60 r/min. 20 min, the second mixture was prepared; the second mixture was dried at 100 ° C for 20 min, and cooled to room temperature to prepare a second mixture.

3. Preparation of the mixture

The second mixture was placed in a planetary mixer for vacuum agitation. The stirring speed of the planetary mixer was 60 r/min, the temperature was 120 ° C, and after stirring for 40 min, it was taken out to obtain a mixture.

4, calendering treatment

The thermal conductivity of the high thermal conductive composite interface material was measured by a Ruiling LW9389 instrument, and the thermal conductivity was measured to be 2.0 W/m·K.

It can be seen from the results of the examples and the comparative examples that in the comparative example, since the polyhedral thermal conductive powder is not added, the thermal conductivity of the obtained material is low, and the high thermal conductive composite interface material of the embodiment of the present invention increases the thermal conductivity by adding the polyhedral thermal conductive powder. The channel makes the thermal conductivity of the thermal interface material greatly improved, and the thermal conductivity can be as high as 5.0-7.2 W/m·K.

While the embodiments of the present invention have been described in detail above, the present invention is not limited thereto, and those skilled in the art can make modifications according to the embodiments of the present invention. Therefore, various modifications in accordance with the embodiments of the present invention should be understood as It falls within the scope of protection of the present invention.

Industrial applicability

The present application provides a high thermal conductive composite interface material, including a silicone polymer, a thermal conductive powder, and an auxiliary agent, wherein the thermal conductive powder includes a spherical thermal conductive powder and a polyhedral thermal conductive powder, wherein the silicone polymer The weight ratio of the spherical thermal powder, the polyhedral thermal powder and the auxiliary agent is 5-10 for the silicone polymer, 75-90 for the spherical thermal powder, 1-5 for the polyhedron, and 0.5-1 for the auxiliary. The present application also provides a preparation method of a polyhedral high thermal conductive composite interface material, which is prepared by mixing and treating a silicone polymer, a thermal conductive powder and an auxiliary agent to obtain a high thermal conductive composite interface material, wherein the thermal conduction The powder includes a spherical heat conductive powder and a polyhedral heat conductive powder. The present application increases the thermal conductivity by using polyhedral thermal powder to increase the contact surface of each material, and the thermal conductivity of the prepared high thermal conductive composite interface material is as high as 5.0-7.2 W/m·K.

Claims

A high thermal conductive composite interface material comprises a silicone polymer, a thermal conductive powder and an auxiliary agent, and the thermal conductive powder comprises a spherical thermal conductive powder and a polyhedral thermal conductive powder.
The high thermal conductive composite interface material according to claim 1, wherein the spherical thermal conductive powder and the polyhedral thermal conductive powder have a weight ratio of spherical thermal conductive powders 75-90 and polyhedral thermal conductive powders 1-5.
The high thermal conductive composite interface material according to claim 1, wherein the silicone polymer, the spherical heat conductive powder, the polyhedral thermal powder and the auxiliary agent are in a weight ratio of silicone polymer 5-10, spherical heat conduction. Powder 75-90, polyhedral thermal powder 1-5, additive 0.5-1.
The high thermal conductive composite interface material according to claim 3, wherein the polyhedral thermally conductive powder is a hexahedron to a dodecahedron, wherein the hexahedron is a combination of a right triangular pyramid and a bottom surface of the inverted triangular vertebral body.
The high thermal conductive composite interface material according to claim 3, wherein the polyhedral thermally conductive powder is a hepahedron to a dodecahedron.
The high thermal conductive composite interface material according to claim 3, wherein the auxiliary agent comprises a coupling agent and a dispersing agent.
A method for preparing a high thermal conductive composite interface material, comprising:

Mixing the silicone polymer, the thermal conductive powder and the auxiliary agent to obtain a mixture;

Performing a calendering treatment on the mixture to obtain the high thermal conductive composite interface material;

Wherein, the heat conductive powder comprises a spherical heat conductive powder and a polyhedral heat conductive powder.
The preparation method according to claim 7, wherein the silicone polymer, the heat conductive powder and the auxiliary agent are subjected to a mixing treatment, comprising:

Drying the spherical thermal conductive powder and the polyhedral thermal conductive powder, and uniformly mixing with the silicone polymer to obtain a first mixture;

Adding an auxiliary agent to the first mixture, mixing uniformly, and then drying to obtain a second mixture;

The second mixture was subjected to vacuum stirring treatment to remove the gas therein to prepare a mixture.
The preparation method according to claim 7, wherein the spherical thermally conductive powder and the polyhedral thermally conductive powder are in a weight ratio of spherical thermally conductive powders 75-90 and polyhedral thermally conductive powders 1-5.
The preparation method according to claim 8, wherein the silicone polymer, the spherical heat conductive powder, the polyhedral heat conductive powder and the auxiliary agent are in a weight ratio of a silicone polymer 5-10, a spherical heat conductive powder 75. -90, polyhedral thermal powder 1-5, auxiliary 0.5-1.