1. The high-adhesion heat-conducting silica gel sheet is characterized by comprising a component A and a component B, wherein the component A comprises the following raw materials in parts by weight: 60-70 parts of vinyl-terminated polymethylvinyl siloxane, 0.5-2 parts of hydrogen-containing methyl silicone oil, 40-300 parts of modified boron carbide, 1-3 parts of methyl vinyl MQ high-viscosity silicon resin, 1-3 parts of allyl glycidyl ether and 1-2 parts of silane coupling agent; the component B comprises the following raw materials in parts by weight: 60-70 parts of vinyl-terminated polymethylvinylsiloxane, 0.5-2 parts of hydrogen-containing methyl silicone oil, 60-150 parts of modified carbon fiber and 20-150 parts of aluminum oxide.

2. The high-adhesion heat-conducting silicone sheet according to claim 1, wherein the hydrogen content of the hydrogen-containing methyl silicone oil is 0.5-0.7%.

3. The high-adhesion heat-conductive silicone sheet according to claim 1, wherein the silane coupling agent is any one of vinyl silane, amino silane, and butadienyl triethoxysilane.

4. The high-adhesion heat-conducting silica gel sheet according to claim 1, wherein the modified boron carbide is prepared by the following method:

s1: dispersing boron carbide and a silane coupling agent in deionized water, and stirring for 30-50min to obtain a reaction solution;

s2: and (4) centrifugally filtering and drying the reaction solution to obtain the modified boron carbide.

5. The high-adhesion heat-conducting silica gel sheet according to claim 1, wherein the modified carbon fiber is prepared by the following steps: and (3) carrying out anodic oxidation treatment for 1-3min in ammonium bicarbonate electrolyte by taking the carbon fiber as an anode and graphite as a cathode to obtain the modified carbon fiber.

6. The high-adhesion heat-conducting silica gel sheet according to claim 1, wherein the mass fraction of the ammonium bicarbonate electrolyte is 8-10%.

7. The high-adhesion heat-conducting silica gel sheet according to claim 1, wherein the oxidation treatment temperature is 25-30 ℃ and the current density is 0.25-0.35A/m²。

8. The process for manufacturing a high-adhesion heat-conducting silicone sheet according to any one of claims 1 to 7, comprising the following steps:

(1) putting the vinyl-terminated polymethylvinyl siloxane, hydrogen-containing methyl silicone oil, modified boron carbide, methyl vinyl MQ high-viscosity silicon resin and allyl glycidyl ether into a stirrer, and stirring at the rotating speed of 800-1500r/min for 20-25min to obtain a component A;

(2) putting the vinyl-terminated polymethylvinylsiloxane, the hydrogen-containing methylsilicone oil, the modified carbon fiber and the alumina into a stirrer, and stirring at the rotating speed of 1200-1800r/min for 25-30min to obtain a component B;

(3) placing 50% of the component A on a substrate, flatly paving, heating for curing and cooling to room temperature;

(4) placing the component B on the sample cured in the step (3), flatly paving, heating for curing and cooling to room temperature;

(5) and (4) placing the rest 50% of the component A on the sample solidified in the step (4), flatly paving the sample, heating the sample for solidification, and cooling the sample to room temperature to obtain the high-adhesiveness heat-conducting silica gel sheet.

Background

In daily life, people can widely apply to various electronic products, because the temperature of electronic components in the electronic products is increased during use, and heat dissipation of the electronic components is needed. For this reason, a fan for heat dissipation is generally disposed in an electronic product having a large volume, but a heat dissipation element having a smaller volume needs to be disposed for heat dissipation due to insufficient internal space of the product in the electronic product having a small volume. When the heat dissipation element is connected to the heat generation element, it is generally necessary to fill the gap between the heat generation element and the heat dissipation element with a filler material and a thermally conductive material. A heat conductive silicone sheet is a commonly used heat conductive interface material.

The heat-conducting silica gel sheet in the prior art usually takes metal oxide as a filler, and has the problems of relatively common strength and adhesive force. To solve the above problems, we propose a highly adhesive heat-conductive silicone sheet and a process for producing the same.

Disclosure of Invention

In view of the deficiencies of the prior art, the present invention provides a high adhesion thermal conductive silicone rubber sheet and a manufacturing process thereof, so as to overcome the problems mentioned in the background art.

In order to achieve the above purpose, the technical scheme of the invention is realized by the following technical scheme: the high-adhesion heat-conducting silica gel sheet comprises a component A and a component B, wherein the component A comprises the following raw materials in parts by weight: 60-70 parts of vinyl-terminated polymethylvinyl siloxane, 0.5-2 parts of hydrogen-containing methyl silicone oil, 40-300 parts of modified boron carbide, 1-3 parts of methyl vinyl MQ high-viscosity silicon resin, 1-3 parts of allyl glycidyl ether and 1-2 parts of silane coupling agent; the component B comprises the following raw materials in parts by weight: 60-70 parts of vinyl-terminated polymethylvinylsiloxane, 0.5-2 parts of hydrogen-containing methyl silicone oil, 60-150 parts of modified carbon fiber and 20-150 parts of aluminum oxide.

Preferably, the hydrogen content of the hydrogen-containing methyl silicone oil is 0.5-0.7%.

Preferably, the silane coupling agent is any one of vinyl silane, amino silane and butadiene-based triethoxy silane.

Preferably, the preparation method of the modified boron carbide comprises the following steps:

s1: dispersing boron carbide and a silane coupling agent in deionized water, and stirring for 30-50min to obtain a reaction solution;

s2: and (4) centrifugally filtering and drying the reaction solution to obtain the modified boron carbide.

Preferably, the preparation method of the modified carbon fiber comprises the following steps: and (3) carrying out anodic oxidation treatment for 1-3min in ammonium bicarbonate electrolyte by taking the carbon fiber as an anode and graphite as a cathode to obtain the modified carbon fiber.

Preferably, the mass fraction of the ammonium bicarbonate electrolyte is 8-10%.

Preferably, the oxidation treatment temperature is 25-30 ℃, and the current density is 0.25-0.35A/m²。

The invention also provides a manufacturing process of the high-adhesion heat-conducting silica gel sheet, which specifically comprises the following steps:

(1) putting the vinyl-terminated polymethylvinyl siloxane, hydrogen-containing methyl silicone oil, modified boron carbide, methyl vinyl MQ high-viscosity silicon resin and allyl glycidyl ether into a stirrer, and stirring at the rotating speed of 800-1500r/min for 20-25min to obtain a component A;

(2) putting the vinyl-terminated polymethylvinylsiloxane, the hydrogen-containing methylsilicone oil, the modified carbon fiber and the alumina into a stirrer, and stirring at the rotating speed of 1200-1800r/min for 25-30min to obtain a component B;

(3) placing 50% of the component A on a substrate, flatly paving, heating for curing and cooling to room temperature;

(4) placing the component B on the sample cured in the step (3), flatly paving, heating for curing and cooling to room temperature;

(5) and (4) placing the rest 50% of the component A on the sample solidified in the step (4), flatly paving the sample, heating the sample for solidification, and cooling the sample to room temperature to obtain the high-adhesiveness heat-conducting silica gel sheet.

The invention has the beneficial effects that:

according to the invention, the modified carbon fiber is added, because the carbon fiber has a smooth surface and poor gum dipping capability, the bonding strength between the carbon fiber and a substrate piece is low, the carbon fiber is used as an anode, graphite is used as a cathode, the surface of the carbon fiber is etched and oxidized by anodic oxidation treatment in ammonium bicarbonate electrolyte, and-COOH, -OH and other groups are connected to the surface of the carbon fiber, so that the surface energy and the roughness of the carbon fiber are improved, the bonding strength between the carbon fiber and the substrate is enhanced, and the overall strength of the heat-conducting silica gel sheet is improved;

according to the invention, the component A is added, and the silane coupling agent is used for modifying boron carbide, so that the uniform dispersion of the boron carbide is facilitated; the added methyl vinyl MQ high-viscosity silicon resin and allyl glycidyl ether improve the bonding strength of the cured component A; and finally, the component A, the component B and the component A are adopted to form a composite interlayer framework, the bonding strength of the component A after curing is better, the strength of the component B after curing is better, the composite interlayer framework ensures the high adhesiveness and the overall strength of the silica gel sheet, and the practicability is good.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described below in conjunction with the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but 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 high-adhesion heat-conducting silica gel sheet comprises a component A and a component B, wherein the component A comprises the following raw materials in parts by weight: 60 parts of vinyl-terminated polymethylvinyl siloxane, 0.5 part of hydrogen-containing methyl silicone oil, 40 parts of modified boron carbide, 1 part of methyl vinyl MQ high-viscosity silicon resin, 1 part of allyl glycidyl ether and 1 part of silane coupling agent; the component B comprises the following raw materials in parts by weight: 60 parts of vinyl-terminated polymethylvinylsiloxane, 0.5 part of hydrogen-containing methyl silicone oil, 60 parts of modified carbon fiber and 20 parts of aluminum oxide.

The hydrogen content of the hydrogen-containing methyl silicone oil is 0.5 percent; the silane coupling agent is vinyl silane.

The preparation method of the modified boron carbide comprises the following steps: s1, dispersing boron carbide and a silane coupling agent in deionized water, and stirring for 30min to obtain a reaction solution; and S2, carrying out centrifugal filtration on the reaction liquid and drying to obtain the modified boron carbide.

The preparation method of the modified carbon fiber comprises the following steps: carrying out anodic oxidation treatment for 1min in ammonium bicarbonate electrolyte by taking carbon fiber as an anode and graphite as a cathode to obtain modified carbon fiber; the mass fraction of the ammonium bicarbonate electrolyte is 8 percent; the oxidation treatment temperature was 25 ℃ and the current density was 0.25A/m²。

The manufacturing process of the high-adhesion heat-conducting silica gel sheet comprises the following steps:

(1) putting the vinyl-terminated polymethylvinyl siloxane, hydrogen-containing methyl silicone oil, modified boron carbide, methyl vinyl MQ high-viscosity silicon resin and allyl glycidyl ether into a stirrer, and stirring at the rotating speed of 800r/min for 20min to obtain a component A;

(2) putting the vinyl-terminated polymethylvinylsiloxane, the hydrogen-containing methylsilicone oil, the modified carbon fiber and the alumina into a stirrer, and stirring at the rotating speed of 1200r/min for 25min to obtain a component B;

(3) placing 50% of the component A on a substrate, flatly paving, heating for curing and cooling to room temperature;

(4) placing the component B on the sample cured in the step (3), flatly paving, heating for curing and cooling to room temperature;

(5) and (4) placing the rest 50% of the component A on the sample solidified in the step (4), flatly paving the sample, heating the sample for solidification, and cooling the sample to room temperature to obtain the high-adhesiveness heat-conducting silica gel sheet.

Example 2

The high-adhesion heat-conducting silica gel sheet comprises a component A and a component B, wherein the component A comprises the following raw materials in parts by weight: 65 parts of vinyl-terminated polymethylvinyl siloxane, 1 part of hydrogen-containing methyl silicone oil, 100 parts of modified boron carbide, 2 parts of methyl vinyl MQ high-viscosity silicon resin, 2 parts of allyl glycidyl ether and 1.5 parts of silane coupling agent; the component B comprises the following raw materials in parts by weight: 60 parts of vinyl-terminated polymethylvinylsiloxane, 1 part of hydrogen-containing methyl silicone oil, 100 parts of modified carbon fiber and 60 parts of aluminum oxide.

The hydrogen content of the hydrogen-containing methyl silicone oil is 0.6 percent; the silane coupling agent is aminosilane.

The preparation method of the modified boron carbide comprises the following steps: s1, dispersing boron carbide and a silane coupling agent in deionized water, and stirring for 40min to obtain a reaction solution; and S2, carrying out centrifugal filtration on the reaction liquid and drying to obtain the modified boron carbide.

The preparation method of the modified carbon fiber comprises the following steps: carrying out anodic oxidation treatment for 1.5min in ammonium bicarbonate electrolyte by taking carbon fiber as an anode and graphite as a cathode to obtain modified carbon fiber; the mass fraction of the ammonium bicarbonate electrolyte is 9 percent; the oxidation treatment temperature was 28 ℃ and the current density was 0.25A/m²。

The manufacturing process of the high-adhesion heat-conducting silica gel sheet comprises the following steps:

(1) putting the vinyl-terminated polymethylvinylsiloxane, hydrogen-containing methylsilicone oil, modified boron carbide, methyl vinyl MQ high-viscosity silicone resin and allyl glycidyl ether into a stirrer, and stirring for 22min at the rotating speed of 1000r/min to obtain a component A;

(2) putting the vinyl-terminated polymethylvinylsiloxane, the hydrogen-containing methylsilicone oil, the modified carbon fiber and the alumina into a stirrer, and stirring at the rotating speed of 1200r/min for 25min to obtain a component B;

(3) placing 50% of the component A on a substrate, flatly paving, heating for curing and cooling to room temperature;

(4) placing the component B on the sample cured in the step (3), flatly paving, heating for curing and cooling to room temperature;

(5) and (4) placing the rest 50% of the component A on the sample solidified in the step (4), flatly paving the sample, heating the sample for solidification, and cooling the sample to room temperature to obtain the high-adhesiveness heat-conducting silica gel sheet.

Example 3

The high-adhesion heat-conducting silica gel sheet comprises a component A and a component B, wherein the component A comprises the following raw materials in parts by weight: 65 parts of vinyl-terminated polymethylvinyl siloxane, 1 part of hydrogen-containing methyl silicone oil, 100 parts of modified boron carbide, 2 parts of methyl vinyl MQ high-viscosity silicon resin, 2 parts of allyl glycidyl ether and 1.5 parts of silane coupling agent; the component B comprises the following raw materials in parts by weight: 60 parts of vinyl-terminated polymethylvinylsiloxane, 1 part of hydrogen-containing methyl silicone oil, 100 parts of modified carbon fiber and 60 parts of aluminum oxide.

The hydrogen content of the hydrogen-containing methyl silicone oil is 0.6 percent; the silane coupling agent is butadiene-based triethoxysilane.

The preparation method of the modified boron carbide comprises the following steps: s1, dispersing boron carbide and a silane coupling agent in deionized water, and stirring for 35min to obtain a reaction solution; and S2, carrying out centrifugal filtration on the reaction liquid and drying to obtain the modified boron carbide.

The preparation method of the modified carbon fiber comprises the following steps: carrying out anodic oxidation treatment for 1-3min in ammonium bicarbonate electrolyte by taking carbon fiber as an anode and graphite as a cathode to obtain modified carbon fiber; the mass fraction of the ammonium bicarbonate electrolyte is 10 percent; the oxidation treatment temperature was 30 ℃ and the current density was 0.3A/m²。

The manufacturing process of the high-adhesion heat-conducting silica gel sheet comprises the following steps:

(1) putting the vinyl-terminated polymethylvinyl siloxane, hydrogen-containing methyl silicone oil, modified boron carbide, methyl vinyl MQ high-viscosity silicon resin and allyl glycidyl ether into a stirrer, and stirring at the rotating speed of 1200r/min for 20min to obtain a component A;

(2) putting the vinyl-terminated polymethylvinylsiloxane, the hydrogen-containing methylsilicone oil, the modified carbon fiber and the alumina into a stirrer, and stirring for 30min at the rotating speed of 1600r/min to obtain a component B;

(3) placing 50% of the component A on a substrate, flatly paving, heating for curing and cooling to room temperature;

(4) placing the component B on the sample cured in the step (3), flatly paving, heating for curing and cooling to room temperature;

(5) and (4) placing the rest 50% of the component A on the sample solidified in the step (4), flatly paving the sample, heating the sample for solidification, and cooling the sample to room temperature to obtain the high-adhesiveness heat-conducting silica gel sheet.

Example 4

The high-adhesion heat-conducting silica gel sheet comprises a component A and a component B, wherein the component A comprises the following raw materials in parts by weight: 70 parts of vinyl-terminated polymethylvinyl siloxane, 2 parts of hydrogen-containing methyl silicone oil, 150 parts of modified boron carbide, 3 parts of methyl vinyl MQ high-viscosity silicon resin, 3 parts of allyl glycidyl ether and 2 parts of silane coupling agent; the component B comprises the following raw materials in parts by weight: 70 parts of vinyl-terminated polymethylvinylsiloxane, 2 parts of hydrogen-containing methyl silicone oil, 120 parts of modified carbon fiber and 30 parts of aluminum oxide.

The hydrogen content of the hydrogen-containing methyl silicone oil is 0.7 percent; the silane coupling agent is vinyl silane.

The preparation method of the modified boron carbide comprises the following steps: s1, dispersing boron carbide and a silane coupling agent in deionized water, and stirring for 50min to obtain a reaction solution; and S2, carrying out centrifugal filtration on the reaction liquid and drying to obtain the modified boron carbide.

The preparation method of the modified carbon fiber comprises the following steps: carrying out anodic oxidation treatment for 3min in ammonium bicarbonate electrolyte by taking carbon fiber as an anode and graphite as a cathode to obtain modified carbon fiber; the mass fraction of the ammonium bicarbonate electrolyte is 10 percent; the oxidation treatment temperature was 30 ℃ and the current density was 0.35A/m²。

The manufacturing process of the high-adhesion heat-conducting silica gel sheet comprises the following steps:

(1) putting the vinyl-terminated polymethylvinyl siloxane, hydrogen-containing methyl silicone oil, modified boron carbide, methyl vinyl MQ high-viscosity silicon resin and allyl glycidyl ether into a stirrer, and stirring at the rotating speed of 1500r/min for 25min to obtain a component A;

(2) putting the vinyl-terminated polymethylvinylsiloxane, the hydrogen-containing methylsilicone oil, the modified carbon fiber and the alumina into a stirrer, and stirring at the rotating speed of 1800r/min for 30min to obtain a component B;

(3) placing 50% of the component A on a substrate, flatly paving, heating for curing and cooling to room temperature;

(4) placing the component B on the sample cured in the step (3), flatly paving, heating for curing and cooling to room temperature;

(5) and (4) placing the rest 50% of the component A on the sample solidified in the step (4), flatly paving the sample, heating the sample for solidification, and cooling the sample to room temperature to obtain the high-adhesiveness heat-conducting silica gel sheet.

Performance detection

The test method comprises the following steps: the high adhesion thermally conductive silicone sheets of examples 1-4 were tested separately, wherein the tensile strength: the method is carried out according to the GB/T529-2008 standard; coefficient of thermal conductivity: reference is made to the ASTM-D5470 standard; initial tack ball number: the test is carried out by using a CNY-1 initial viscosity tester. Specific detection results are shown in table 1.

TABLE 1 Performance test

As can be seen from the above table, the high adhesion heat conductive silicone sheet of the present invention has good adhesion and strength.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.