Multifunctional silica gel gasket and preparation method thereof

Abstract

The invention provides a multifunctional silica gel gasket and a preparation method thereof. The multifunctional silica gel gasket comprises a heat-conducting wave-absorbing layer, a glass fabric, a heat-conducting shielding layer and a heat-conducting insulating layer which are stacked in sequence. And the heat-conducting wave-absorbing layer, the heat-conducting shielding layer and the heat-conducting insulating layer are silica gel layers containing composite inorganic heat-conducting filler. The composite inorganic heat-conducting filler in the heat-conducting wave-absorbing layer comprises aluminum oxide and carbonyl iron powder. The composite inorganic heat-conducting filler in the heat-conducting shielding layer comprises aluminum oxide and copper nickel-plated powder. The composite inorganic heat-conducting filler in the heat-conducting insulating layer comprises boron nitride and aluminum oxide. The multifunctional silica gel gasket has the performances of heat conduction, electromagnetic wave shielding, wave absorption and insulation at the same time, can be used as a buffering silica gel gasket with certain strength, and can meet various requirements of special scenes.

Description

Technical Field

[0001] The present invention relates to the technical field of heat-conducting materials, and in particular to a heat-conducting silicone gasket, and more particularly to a multifunctional silicone gasket and a preparation method thereof. Background Art

[0002] With the rapid development of high-tech fields such as aviation, electronics and electrical, electronic equipment is increasingly moving towards high concentration and miniaturization, and people have put forward higher and more requirements for thermal conductive and heat dissipation materials. In the field of electronics and electrical, due to the rapid development of integration technology and assembly technology, electronic components and logic circuits are moving towards miniaturization and density, and there is a great need for materials with diverse functions. At the same time, it is hoped that thermal conductive materials have excellent comprehensive properties, which can not only provide safe and reliable heat dissipation paths for electronic components, but also play the role of wave absorption, shielding, insulation and shock absorption.

[0003] Wave-absorbing materials can effectively reduce the direct radiation, reflection, diffraction and surface wave radiation of electromagnetic waves in a wide frequency band. They have good reliability and stability, are easy to use, have strong adhesion and long life, and can eliminate the back-and-forth reflection of electromagnetic waves in the shielding cavity and reduce the interference of clutter on the equipment itself.

[0004] Electromagnetic shielding is a technology that uses conductive or magnetic materials to limit electromagnetic radiation within a certain space. Its basic principles include reflection loss and absorption loss. Reflection loss is caused by the mismatch between the wave impedance of the shield and the external space, which causes the electromagnetic waves incident from the external space to be reflected on the surface of the shield. Absorption loss is the absorption of part of the electromagnetic wave energy entering the shield. The principle of electromagnetic shielding can be achieved through the following mechanisms: 1. Reflection loss (SER); 2. Absorption loss (SEA) 3. Internal multiple reflection loss (SEM). Electromagnetic shielding is widely used, including electronics, automobiles, aviation, communications and other fields. By utilizing the reflection, absorption and guidance of the electromagnetic energy flow by the shield, the impact of electromagnetic waves on humans and the environment can be effectively reduced, and the interference of electromagnetic waves on the operation of equipment can be reduced.

[0005] Heat conduction refers to the phenomenon of heat energy transfer generated by the thermal motion of microscopic particles such as molecules, atoms, and free electrons when there is no relative displacement between the parts of an object. This heat transfer method can occur in solids, liquids, and gases, but it is pure heat conduction in solids, while in fluids, the density difference caused by the temperature gradient will produce natural convection, so heat convection and heat conduction occur simultaneously.

[0006] As the heat generated by electronic products increases day by day, thermal management has become a key issue in the industry. Thermally conductive silicone materials have the advantages of high thermal conductivity, good affinity, weather resistance, high and low temperature resistance, and good insulation, and are widely used in the industry.

[0007] However, the current thermally conductive silicone materials are difficult to simultaneously take into account the effects of thermal conductivity, wave absorption, and electromagnetic shielding, and cannot meet the multiple requirements of customers in special scenarios. Summary of the invention

[0008] Based on the above problems, the purpose of the present invention is to provide a multifunctional silicone gasket and a preparation method thereof. The multifunctional silicone gasket can simultaneously have the properties of heat conduction, electromagnetic wave shielding, wave absorption and insulation. As a buffering silicone gasket with a certain strength, it can meet multiple requirements of special scenarios.

[0009] To achieve the above-mentioned objectives, on one hand, the present invention provides a multifunctional silicone gasket, comprising a heat-conducting absorbing layer, a glass fiber cloth, a heat-conducting shielding layer and a heat-conducting insulating layer stacked in sequence, wherein the heat-conducting absorbing layer, the heat-conducting shielding layer and the heat-conducting insulating layer are all silicone layers containing composite inorganic heat-conducting fillers, the composite inorganic heat-conducting fillers in the heat-conducting absorbing layer contain aluminum oxide and carbonyl iron powder, the composite inorganic heat-conducting fillers in the heat-conducting shielding layer contain aluminum oxide and copper-plated nickel powder, and the composite inorganic heat-conducting fillers in the heat-conducting insulating layer contain boron nitride and aluminum oxide.

[0010] The multifunctional silicone gasket of the present invention has at least the following technical effects.

[0011] (1) A heat-conducting absorbing layer is arranged on one side of the glass fiber cloth, and a heat-conducting shielding layer and a heat-conducting insulating layer are arranged in sequence on the other side. The glass fiber cloth is arranged in the middle to increase the strength of the three functional layers at the same time.

[0012] (2) The heat-conducting wave-absorbing layer, the heat-conducting shielding layer and the heat-conducting insulating layer are all silicone layers containing composite inorganic heat-conducting fillers. The silicone layer has a certain elasticity, so that the gasket has a good buffering effect. Due to the stability of silicone, the gasket also has good weather resistance and high temperature resistance.

[0013] (3) The composite inorganic thermal conductive filler in the thermal conductive absorbing layer includes aluminum oxide and carbonyl iron powder, wherein aluminum oxide plays a role of lubrication and thermal conductivity, and carbonyl iron powder can absorb electromagnetic waves of different frequency bands. The composite inorganic thermal conductive filler in the thermal conductive shielding layer includes aluminum oxide and copper-plated nickel powder, wherein aluminum oxide plays a role of lubrication and thermal conductivity, and copper-plated nickel powder can shield electromagnetic waves that are not absorbed. The composite inorganic thermal conductive filler in the thermal conductive insulating layer includes boron nitride and aluminum oxide, wherein aluminum oxide plays a role of lubrication and thermal conductivity, and boron nitride has an extremely high thermal conductivity coefficient, which can not only increase the thermal conductivity of the entire product, but also reduce the dielectric constant and play a good insulation role.

[0014] (4) Since the copper-plated nickel powder has a certain conductivity and the thermal conductive shielding layer is a non-insulating layer, it can be wrapped by the insulating layers on both sides when placed in the middle, so that the entire silicone gasket has insulating properties. Therefore, it satisfies the need for a functional layer of non-insulating material while making the entire silicone gasket insulating.

[0015] In summary, the present invention provides three functional layers of glass fiber cloth, heat-conducting absorbing layer, heat-conducting shielding layer and heat-conducting insulating layer, so that the silicone gasket has the characteristics of heat conduction, electromagnetic wave shielding, wave absorption and insulation, and also has a certain strength and buffering function, which can meet multiple requirements of special scenarios.

[0016] Preferably, the glass fiber cloth has a mesh size of 40 to 60 and a thickness of 0.01 to 0.03 mm.

[0017] Preferably, the raw materials for preparing the thermal conductive wave absorbing layer include, by weight, 7 to 15 parts of vinyl silicone oil, 0.1 to 0.5 parts of hydrogenated silicone oil, 0.01 to 0.05 parts of catalyst, 0.02 to 0.10 parts of silane coupling agent, 1 to 10 parts of aluminum oxide and 15 to 40 parts of carbonyl iron powder.

[0018] Preferably, the raw materials for preparing the thermal conductive shielding layer include, by weight, 7 to 15 parts of vinyl silicone oil, 0.1 to 0.5 parts of hydrogenated silicone oil, 0.01 to 0.05 parts of catalyst, 0.01 to 0.10 parts of color powder, 0.02 to 0.10 parts of silane coupling agent, 1 to 10 parts of aluminum oxide and 15 to 50 parts of copper-plated nickel powder.

[0019] Preferably, in parts by weight, the raw materials for preparing the thermally conductive insulating layer include 7 to 15 parts of vinyl silicone oil, 0.1 to 0.5 parts of hydrogenated silicone oil, 0.01 to 0.05 parts of catalyst, 0.01 to 0.10 parts of color powder, 0.02 to 0.10 parts of silane coupling agent, 5 to 25 parts of aluminum oxide and 1 to 15 parts of boron nitride.

[0020] Preferably, the viscosity of the vinyl silicone oil at 25°C is 500-5000 mm 2 / s, vinyl content is 0.3~1.2%.

[0021] Preferably, the catalyst comprises H 2 PtCl 6 、[(CH 2 =CHSiMe 2 ) 2 O] 2 Pt, (PPh 3 ) 2 Pt-(CH 2 =CH 2 ), (PPh 3 ) 3 RhCl, Rh2 (OAc) 4 、RhH(CO)(PPh 3 ) 3 and [Rh(COD) 2 ]BF 4 -(PPh 3 ) 3 At least one of .

[0022] Preferably, the silane coupling agent includes at least one of A-150, A-151, A-171, A-172, KH-550, KH-560 and KH-570.

[0023] Preferably, the color powder includes at least one of golden C red, sun-fast brilliant red, sun-fast red, sun-fast deep red, permanent pink, permanent red, permanent red, bright red pink, litho carmine, pigment ruby, magenta, permanent rose red, red lotus, sun-fast lotus color source, permanent purple, sun-fast yellow, permanent yellow, benzidine yellow, lemon yellow, medium chrome yellow, sun-fast orange, permanent orange, phthalocyanine blue, phthalocyanine green, ultramarine, art green, iron red, iron yellow and iron black.

[0024] The second aspect of the present invention provides a method for preparing a multifunctional silicone gasket, comprising the steps of:

[0025] (1) mixing the raw materials for preparing each layer of the heat conductive absorbing layer, the heat conductive shielding layer and the heat conductive insulating layer in a mixer to obtain slurry of each layer;

[0026] (2) coating the slurry of the heat-conducting and wave-absorbing layer on one side of the glass fiber cloth;

[0027] (3) first coating the slurry of the thermal conductive shielding layer on the other side of the glass fiber cloth, and then coating the slurry of the thermal conductive insulation layer;

[0028] (4) Baking.

[0029] The glass fiber cloth usually has mesh holes, and the heat-conducting absorbing layer, the heat-conducting shielding layer and the heat-conducting insulating layer can be compounded on the glass fiber cloth through a coating process and then baking. DETAILED DESCRIPTION

[0030] The multifunctional silicone gasket of the present invention has good thermal conductivity, electromagnetic wave shielding, wave absorption, insulation and buffering properties, and has a certain strength, and can meet the use requirements of highly centralized and miniaturized development in high-tech fields such as aviation, electronics and electrical.

[0031] The multifunctional silicone gasket of the present invention is a multi-layer structure. The multifunctional silicone gasket comprises a glass fiber cloth, a heat-conducting wave-absorbing layer is arranged on one side of the glass fiber cloth, and a heat-conducting shielding layer and a heat-conducting insulating layer are arranged in sequence on the other side. The heat-conducting wave-absorbing layer, the heat-conducting shielding layer and the heat-conducting insulating layer constitute a multifunctional layer.

[0032] Among them, the glass fiber cloth has a mesh size of 40 to 60 and a thickness of 0.01 to 0.03 mm. The pore size of the glass fiber cloth is relatively large, and the slurry of the functional layers on both sides can be contacted and compounded together through the pore size of the glass fiber cloth. The glass fiber cloth has a good reinforcing effect, and one layer of glass fiber cloth can increase the strength of three functional layers at the same time.

[0033] The thickness of the heat-conducting wave-absorbing layer is 0.3 to 10.0 mm. In terms of weight, the raw materials for preparing the heat-conducting wave-absorbing layer include 7 to 15 parts of vinyl silicone oil, 0.1 to 0.5 parts of hydrogenated silicone oil, 0.01 to 0.05 parts of catalyst, 0.02 to 0.10 parts of silane coupling agent, 1 to 10 parts of aluminum oxide and 15 to 40 parts of carbonyl iron powder. As an example, the vinyl silicone oil can be, but is not limited to, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, and 15 parts. The viscosity of the vinyl silicone oil at 25°C is 500 to 5000 mm 2 / s, the vinyl content is 0.3-1.2%. As an example, the viscosity of the vinyl silicone oil can be, but is not limited to, 500 mm 2 / s、1000mm 2 / s、1500mm 2 / s、2000mm 2 / s、2500mm 2 / s、3000mm 2 / s、3500mm 2 / s、4000mm 2 / s、4500mm 2 / s、5000mm 2 / s, the vinyl content can be but not limited to 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%. The hydrogen-containing silicone oil can be but not limited to 0.1 part, 0.2 part, 0.3 part, 0.4 part, 0.5 part. Vinyl silicone oil and hydrogen-containing silicone oil undergo hydrosilylation reaction under the action of a catalyst to form a silica gel layer. The catalyst can be but not limited to 0.01 part, 0.02 part, 0.03 part, 0.04 part, 0.05 part. The catalyst includes H 2 PtCl 6 、[(CH 2 =CHSiMe 2 ) 2 O] 2 Pt, (PPh 3 ) 2 Pt-(CH 2 =CH 2 ), (PPh 3 ) 3 RhCl, Rh 2 (OAc)4 、RhH(CO)(PPh 3 ) 3 and [Rh(COD) 2 ]BF 4 -(PPh 3 ) 3 At least one of. The silane coupling agent can be, but is not limited to, 0.02 parts, 0.03 parts, 0.04 parts, 0.05 parts, 0.06 parts, 0.07 parts, 0.08 parts, 0.09 parts, and 0.10 parts. The silane coupling agent includes at least one of A-150, A-151, A-171, A-172, KH-550, KH-560, and KH-570. The silane coupling agent can be used as a surface modifier to improve the interface between the composite inorganic thermal conductive filler and the silica gel to improve the performance of the silica gel gasket. Alumina can be, but is not limited to, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, and 10 parts. Carbonyl iron powder can be, but is not limited to, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, and 40 parts. Alumina and carbonyl iron powder are dispersed in the silica gel layer.

[0034] The thickness of the thermal conductive shielding layer is 0.3 to 10.0 mm. In terms of weight, the raw materials for preparing the thermal conductive shielding layer include 7 to 15 parts of vinyl silicone oil, 0.1 to 0.5 parts of hydrogenated silicone oil, 0.01 to 0.05 parts of catalyst, 0.01 to 0.10 parts of color powder, 0.02 to 0.10 parts of silane coupling agent, 1 to 10 parts of aluminum oxide and 15 to 50 parts of copper-plated nickel powder. As an example, the vinyl silicone oil can be, but is not limited to, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, and 15 parts. The viscosity of the vinyl silicone oil at 25°C is 500 to 5000 mm 2 / s, the vinyl content is 0.3-1.2%. As an example, the viscosity of the vinyl silicone oil can be, but is not limited to, 500 mm 2 / s、1000mm 2 / s、1500mm 2 / s、2000mm 2 / s、2500mm 2 / s、3000mm 2 / s、3500mm 2 / s、4000mm 2 / s、4500mm 2 / s、5000mm 2 / s, the vinyl content can be but not limited to 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%. The hydrogen-containing silicone oil can be but not limited to 0.1 part, 0.2 part, 0.3 part, 0.4 part, 0.5 part. Vinyl silicone oil and hydrogen-containing silicone oil undergo hydrosilylation reaction under the action of a catalyst to form a silica gel layer. The catalyst can be but not limited to 0.01 part, 0.02 part, 0.03 part, 0.04 part, 0.05 part. The catalyst includes H 2 PtCl 6 、[(CH 2 =CHSiMe 2 ) 2 O] 2 Pt, (PPh 3 ) 2 Pt-(CH 2 =CH 2 ), (PPh 3 ) 3 RhCl, Rh 2 (OAc) 4 、RhH(CO)(PPh 3 ) 3 and [Rh(COD) 2 ]BF 4 -(PPh 3 ) 3At least one of the following. The color powder may be, but is not limited to, 0.01 part, 0.02 part, 0.03 part, 0.04 part, 0.05 part, 0.06 part, 0.07 part, 0.08 part, 0.09 part, and 0.10 part. The color powder includes at least one of golden light C red, fast red, fast red, fast dark red, permanent pink, permanent red, permanent red, permanent red, red powder, lithocarb, pigment red, magenta, permanent rose red, red lotus, fast lotus color source, permanent purple, fast yellow, permanent yellow, benzidine yellow, lemon yellow, medium chrome yellow, fast orange, permanent orange, phthalocyanine blue, phthalocyanine green, ultramarine, art green, iron red, iron yellow, and iron black. The silane coupling agent can be, but is not limited to, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, and 0.10 parts. The silane coupling agent includes at least one of A-150, A-151, A-171, A-172, KH-550, KH-560, and KH-570. The silane coupling agent can be used as a surface modifier to improve the interface between the composite inorganic thermal conductive filler and the silica gel to improve the performance of the silica gel gasket. Alumina can be, but is not limited to, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, and 10 parts. Copper-plated nickel powder can be, but is not limited to, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, and 50 parts. Alumina and copper-plated nickel powder are dispersed in the silica gel layer.

[0035] The thickness of the thermally conductive insulating layer is 0.3 to 10.0 mm. In terms of weight, the raw materials for preparing the thermally conductive insulating layer include 7 to 15 parts of vinyl silicone oil, 0.1 to 0.5 parts of hydrogenated silicone oil, 0.01 to 0.05 parts of catalyst, 0.01 to 0.10 parts of color powder, 0.02 to 0.10 parts of silane coupling agent, 5 to 25 parts of aluminum oxide and 1 to 15 parts of boron nitride. As an example, the vinyl silicone oil can be, but is not limited to, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, and 15 parts. The viscosity of the vinyl silicone oil at 25°C is 500 to 5000 mm 2 / s, the vinyl content is 0.3-1.2%. As an example, the viscosity of the vinyl silicone oil can be, but is not limited to, 500 mm 2 / s、1000mm 2 / s、1500mm 2 / s、2000mm 2 / s、2500mm 2 / s、3000mm 2 / s、3500mm 2 / s、4000mm 2 / s、4500mm 2 / s、5000mm 2 / s, the vinyl content can be but not limited to 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%. The hydrogen-containing silicone oil can be but not limited to 0.01 parts, 0.02 parts, 0.03 parts, 0.04 parts, 0.05 parts. Vinyl silicone oil and hydrogen-containing silicone oil react with hydrogen silylation under the action of a catalyst to form a silica gel layer. The catalyst can be but not limited to 0.01 parts, 0.02 parts, 0.03 parts, 0.04 parts, 0.05 parts. The catalyst includes H 2 PtCl 6 、[(CH 2 =CHSiMe 2 ) 2 O] 2 Pt, (PPh 3 ) 2 Pt-(CH 2 =CH 2 ), (PPh 3 ) 3 RhCl, Rh 2 (OAc) 4 、RhH(CO)(PPh 3 ) 3 and [Rh(COD) 2 ]BF 4 -(PPh 3 ) 3At least one of the following. The color powder may be, but is not limited to, 0.01 part, 0.02 part, 0.03 part, 0.04 part, 0.05 part, 0.06 part, 0.07 part, 0.08 part, 0.09 part, and 0.10 part. The color powder includes at least one of golden light C red, fast red, fast red, fast dark red, permanent pink, permanent red, permanent red, permanent red, red powder, lithocarb, pigment red, magenta, permanent rose red, red lotus, fast lotus color source, permanent purple, fast yellow, permanent yellow, benzidine yellow, lemon yellow, medium chrome yellow, fast orange, permanent orange, phthalocyanine blue, phthalocyanine green, ultramarine, art green, iron red, iron yellow, and iron black. The silane coupling agent can be, but is not limited to, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.10 parts. The silane coupling agent includes at least one of A-150, A-151, A-171, A-172, KH-550, KH-560, and KH-570. The silane coupling agent can be used as a surface modifier to improve the interface between the composite inorganic thermal conductive filler and the silica gel to improve the performance of the silica gel gasket. Alumina can be, but is not limited to, 5, 10, 15, 20, and 25 parts. Boron nitride can be, but is not limited to, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, and 15 parts. Aluminum oxide and boron nitride are dispersed in the silica gel layer.

[0036] The preparation method of the multifunctional silica gel gasket of the present invention comprises the steps of:

[0037] (1) mixing the raw materials for preparing each layer of the heat conductive absorbing layer, the heat conductive shielding layer and the heat conductive insulating layer in a mixer to obtain slurry of each layer;

[0038] (2) coating a heat-conducting and wave-absorbing layer slurry on one side of the glass fiber cloth;

[0039] (3) firstly apply the slurry of the thermal conductive shielding layer to the other side of the glass fiber cloth, and then apply the slurry of the thermal conductive insulation layer;

[0040] (4) Baking.

[0041] The raw materials for preparing each layer are mixed in a planetary mixer to obtain the slurry of each layer. The planetary mixer can first stir at a speed of 5 to 20 r / min for 5 to 20 minutes, then increase the speed to 40 to 100 r / min for 30 to 120 minutes, and evacuate while stirring. After coating with a coating machine, it can be baked in an oven at 120 to 180°C for 5 to 30 minutes, so that the three-layer slurry is compounded on the glass fiber cloth to form an integrated multifunctional silicone gasket. Each layer has its own function, and the three-layer preparation raw materials use the silicone layer as a carrier, so they can be well compounded.

[0042] In order to better illustrate the purpose, technical scheme and beneficial effects of the present invention, the present invention will be further described below in conjunction with specific embodiments. It should be noted that the following implementation method is a further explanation of the present invention and should not be used as a limitation of the present invention.

[0043] Example 1

[0044] This embodiment is a multifunctional silicone gasket, comprising a heat-conducting wave-absorbing layer, a glass fiber cloth, a heat-conducting shielding layer and a heat-conducting insulating layer stacked in sequence. The glass fiber cloth is 50 mesh and 0.02 mm thick. In terms of weight, the raw materials for preparing the heat-conducting wave-absorbing layer include 10 parts of vinyl silicone oil (with a viscosity of 1500 mm at 25°C). 2 / s, vinyl content of 0.58%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts of H 2 PtCl 6 , 0.04 parts of KH-560, 5 parts of aluminum oxide and 25 parts of carbonyl iron powder. The raw materials for preparing the thermal conductive shielding layer include 10 parts of vinyl silicone oil (viscosity of 1000mm at 25°C) 2 / s, vinyl content of 0.76%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts of H 2 PtCl 6 , 0.05 parts of Jinguang C red, 0.04 parts of KH-560, 5 parts of aluminum oxide and 30 parts of copper-plated nickel powder. The raw materials for the preparation of the thermal conductive insulation layer include 10 parts of vinyl silicone oil (viscosity of 2000mm at 25°C) 2 / s, vinyl content of 0.46%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts of H 2 PtCl 6 , 0.025 parts of Jinguang C Red, 0.04 parts of KH-560, 10 parts of aluminum oxide and 8 parts of boron nitride.

[0045] The preparation method of the multifunctional silica gel gasket of this embodiment comprises the following steps:

[0046] (1) The raw materials for preparing each layer of the heat conductive absorbing layer, the heat conductive shielding layer and the heat conductive insulating layer are mixed in a planetary mixer to obtain slurries of each layer, and the planetary mixer is stirred at a speed of 15 r / min for 15 min, and then the speed is increased to 60 r / min and stirred for 60 min, and vacuum is drawn while stirring;

[0047] (2) coating one side of the glass fiber cloth with a slurry of a heat-conducting and wave-absorbing layer by a coating machine;

[0048] (3) firstly apply the slurry of the thermal conductive shielding layer to the other side of the glass fiber cloth, and then apply the slurry of the thermal conductive insulation layer;

[0049] (4) After coating, bake in an oven at 150°C for 15 minutes.

[0050] Example 2

[0051] This embodiment is a multifunctional silicone gasket, comprising a heat-conducting wave-absorbing layer, a glass fiber cloth, a heat-conducting shielding layer and a heat-conducting insulating layer stacked in sequence. The glass fiber cloth is 60 mesh and 0.015 mm thick. In terms of weight, the raw materials for preparing the heat-conducting wave-absorbing layer include 15 parts of vinyl silicone oil (with a viscosity of 1000 mm at 25°C). 2 / s, vinyl content of 0.76%), 0.4 parts of hydrogen-containing silicone oil, 0.05 parts of H 2 PtCl 6 , 0.06 parts of KH-560, 8 parts of aluminum oxide and 20 parts of carbonyl iron powder. The raw materials for preparing the thermal conductive shielding layer include 10 parts of vinyl silicone oil (viscosity of 1000mm at 25°C) 2 / s, vinyl content of 0.76%), 0.1 parts of hydrogen-containing silicone oil, 0.01 parts of H 2 PtCl 6 , 0.07 parts of Jinguang C red, 0.08 parts of KH-560, 8 parts of aluminum oxide and 25 parts of copper-plated nickel powder. The raw materials for the preparation of the thermal insulation layer include 12 parts of vinyl silicone oil (viscosity of 1500mm at 25°C) 2 / s, vinyl content is 0.58%), 0.3 parts of hydrogen-containing silicone oil, 0.015 parts of H 2 PtCl 6 , 0.05 parts of Jinguang C Red, 0.08 parts of KH-560, 15 parts of aluminum oxide and 10 parts of boron nitride.

[0052] The preparation method of the multifunctional silica gel gasket of this embodiment comprises the following steps:

[0053] (1) The raw materials for preparing each layer of the heat conductive absorbing layer, the heat conductive shielding layer and the heat conductive insulating layer are mixed in a planetary mixer to obtain slurries of each layer, and the planetary mixer is stirred at a speed of 18 r / min for 15 min, and then the speed is increased to 80 r / min and stirred for 45 min, and vacuum is drawn while stirring;

[0054] (2) coating one side of the glass fiber cloth with a slurry of a heat-conducting and wave-absorbing layer by a coating machine;

[0055] (3) firstly apply the slurry of the thermal conductive shielding layer to the other side of the glass fiber cloth, and then apply the slurry of the thermal conductive insulation layer;

[0056] (4) After coating, bake in an oven at 180°C for 5 minutes.

[0057] Example 3

[0058] This embodiment is a multifunctional silicone gasket, comprising a heat-conducting wave-absorbing layer, a glass fiber cloth, a heat-conducting shielding layer and a heat-conducting insulating layer stacked in sequence. The glass fiber cloth is 50 mesh and 0.015 mm thick. In terms of weight, the raw materials for preparing the heat-conducting wave-absorbing layer include 10 parts of vinyl silicone oil (viscosity of 1500 mm at 25°C) 2 / s, vinyl content of 0.58%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts of [Rh(COD) 2 ]BF 4 -(PPh 3 ) 3 , 0.04 parts of A-151, 5 parts of aluminum oxide and 25 parts of carbonyl iron powder. The raw materials for preparing the thermal conductive shielding layer include 10 parts of vinyl silicone oil (viscosity of 1000mm at 25°C) 2 / s, vinyl content of 0.76%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts (PPh 3 ) 3 RhCl, 0.06 parts of Permanent Yellow, 0.04 parts of KH-550, 5 parts of aluminum oxide and 30 parts of copper-plated nickel powder. The raw materials for the preparation of the thermal insulation layer include 10 parts of vinyl silicone oil (viscosity of 2000mm at 25°C) 2 / s, vinyl content is 0.46%), 0.15 parts of hydrogen-containing silicone oil, 0.03 parts (PPh 3 ) 2 Pt-(CH 2 =CH 2 ), 0.02 parts of lemon yellow, 0.04 parts of A-151, 10 parts of aluminum oxide and 8 parts of boron nitride.

[0059] The preparation method of the multifunctional silica gel gasket of this embodiment comprises the following steps:

[0060] (1) The raw materials for preparing each layer of the heat conductive absorbing layer, the heat conductive shielding layer and the heat conductive insulating layer are mixed in a planetary mixer to obtain slurries of each layer, and the planetary mixer is stirred at a speed of 10 r / min for 15 min, and then the speed is increased to 60 r / min and stirred for 60 min, and vacuum is drawn while stirring;

[0061] (2) coating one side of the glass fiber cloth with a slurry of a heat-conducting and wave-absorbing layer by a coating machine;

[0062] (3) firstly apply the slurry of the thermal conductive shielding layer to the other side of the glass fiber cloth, and then apply the slurry of the thermal conductive insulation layer;

[0063] (4) After coating, bake in an oven at 150°C for 15 minutes.

[0064] Comparative Example 1

[0065] This comparative example is a multifunctional silicone gasket, which includes a first layer, a glass fiber cloth, a second layer and a third layer stacked in sequence. The glass fiber cloth is 50 mesh and 0.02 mm thick. In terms of weight, the raw materials for preparing the first layer include 10 parts of vinyl silicone oil (viscosity of 1500 mm at 25°C) 2 / s, vinyl content of 0.58%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts of H 2 PtCl 6 , 0.04 parts of KH-560 and 30 parts of aluminum oxide. The second layer is prepared by 10 parts of vinyl silicone oil (viscosity of 1000 mm at 25°C) 2 / s, vinyl content of 0.76%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts of H 2 PtCl 6 , 0.05 parts of Jinguang C Red, 0.04 parts of KH-560 and 35 parts of aluminum oxide. The raw materials for the preparation of the third layer include 10 parts of vinyl silicone oil (viscosity of 2000mm at 25°C) 2 / s, vinyl content of 0.46%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts of H 2 PtCl 6 , 0.025 parts of Jinguang C Red, 0.04 parts of KH-560 and 18 parts of aluminum oxide.

[0066] The preparation method of the multifunctional silica gel gasket of this comparative example comprises the following steps:

[0067] (1) The raw materials for preparing each layer of the first layer, the second layer and the third layer are mixed in a planetary mixer to obtain slurries of each layer. The planetary mixer is stirred at a speed of 15 r / min for 15 min, and then the speed is increased to 60 r / min and stirred for 60 min, and vacuum is drawn while stirring;

[0068] (2) coating the first layer of slurry on one side of the glass fiber cloth using a coating machine;

[0069] (3) first apply the second layer of slurry on the other side of the fiberglass cloth, and then apply the third layer of slurry;

[0070] (4) After coating, bake in an oven at 150°C for 15 minutes.

[0071] Comparative Example 2

[0072] This comparative example is a multifunctional silicone gasket, which includes a first layer, a glass fiber cloth, a second layer and a third layer stacked in sequence. The glass fiber cloth is 50 mesh and 0.02 mm thick. In terms of weight, the raw materials for preparing the first layer include 10 parts of vinyl silicone oil (viscosity of 1500 mm at 25°C) 2 / s, vinyl content of 0.58%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts of H2 PtCl 6 , 0.04 parts KH-560, 30 parts aluminum oxide. The second layer preparation raw materials include 10 parts vinyl silicone oil (viscosity of 1000mm at 25°C) 2 / s, vinyl content of 0.76%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts of H 2 PtCl 6 , 0.05 parts of Jinguang C red, 0.04 parts of KH-560, 5 parts of aluminum oxide and 30 parts of copper-plated nickel powder. The raw materials for the preparation of the third layer include 10 parts of vinyl silicone oil (viscosity of 2000mm at 25°C) 2 / s, vinyl content of 0.46%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts of H 2 PtCl 6 , 0.025 parts of Jinguang C Red, 0.04 parts of KH-560, 10 parts of aluminum oxide and 8 parts of boron nitride.

[0073] The preparation method of the multifunctional silica gel gasket of this comparative example comprises the following steps:

[0074] (1) The raw materials for preparing each layer of the first layer, the second layer and the third layer are mixed in a planetary mixer to obtain slurries of each layer. The planetary mixer is stirred at a speed of 15 r / min for 15 min, and then the speed is increased to 60 r / min and stirred for 60 min, and vacuum is drawn while stirring;

[0075] (2) coating the first layer of slurry on one side of the glass fiber cloth using a coating machine;

[0076] (3) first apply the second layer of slurry on the other side of the fiberglass cloth, and then apply the third layer of slurry;

[0077] (4) After coating, bake in an oven at 150°C for 15 minutes.

[0078] Comparative Example 3

[0079] This comparative example is a multifunctional silicone gasket, which includes a first layer, a glass fiber cloth, a second shielding layer and a third layer stacked in sequence. The glass fiber cloth is 50 mesh and 0.02 mm thick. In terms of weight, the raw materials for preparing the first layer include 10 parts of vinyl silicone oil (viscosity of 1500 mm at 25°C) 2 / s, vinyl content of 0.58%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts of H 2 PtCl 6 , 0.04 parts of KH-560, 5 parts of alumina and 25 parts of carbonyl iron powder. The second layer is prepared by 10 parts of vinyl silicone oil (viscosity of 1000 mm at 25°C) 2 / s, vinyl content of 0.76%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts of H 2 PtCl 6 , 0.05 parts of Jinguang C Red, 0.04 parts of KH-560 and 35 parts of aluminum oxide. The raw materials for the preparation of the third layer include 10 parts of vinyl silicone oil (viscosity of 2000mm at 25°C) 2 / s, vinyl content of 0.46%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts of H 2 PtCl 6 , 0.025 parts of Jinguang C Red, 0.04 parts of KH-560, 10 parts of aluminum oxide and 8 parts of boron nitride.

[0080] The preparation method of the multifunctional silica gel gasket of this comparative example comprises the following steps:

[0081] (1) The raw materials for preparing each layer of the first layer, the second layer and the third layer are mixed in a planetary mixer to obtain slurries of each layer. The planetary mixer is stirred at a speed of 15 r / min for 15 min, and then the speed is increased to 60 r / min and stirred for 60 min, and vacuum is drawn while stirring;

[0082] (2) coating the first layer of slurry on one side of the glass fiber cloth using a coating machine;

[0083] (3) first apply the second layer of slurry on the other side of the fiberglass cloth, and then apply the third layer of slurry;

[0084] (4) After coating, bake in an oven at 150°C for 15 minutes.

[0085] Comparative Example 4

[0086] This comparative example is a multifunctional silicone gasket, which includes a first layer, a glass fiber cloth, a second layer and a third layer stacked in sequence. The glass fiber cloth is 50 mesh and 0.02 mm thick. In terms of weight, the raw materials for preparing the first layer include 10 parts of vinyl silicone oil (viscosity of 1500 mm at 25°C) 2 / s, vinyl content of 0.58%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts of H 2 PtCl 6 , 0.04 parts of KH-560, 5 parts of alumina and 25 parts of carbonyl iron powder. The second layer is prepared by 10 parts of vinyl silicone oil (viscosity of 1000 mm at 25°C) 2 / s, vinyl content of 0.76%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts of H 2 PtCl 6 , 0.05 parts of Jinguang C red, 0.04 parts of KH-560, 5 parts of aluminum oxide and 30 parts of copper-plated nickel powder. The raw materials for the preparation of the third layer include 10 parts of vinyl silicone oil (viscosity of 2000mm at 25°C)2 / s, vinyl content of 0.46%), 0.15 parts of hydrogen-containing silicone oil, 0.035 parts of H 2 PtCl 6 , 0.025 parts of Jinguang C Red, 0.04 parts of KH-560 and 18 parts of aluminum oxide.

[0087] The preparation method of the multifunctional silica gel gasket of this comparative example comprises the following steps:

[0088] (1) The raw materials for preparing each layer of the first layer, the second layer and the third layer are mixed in a planetary mixer to obtain slurries of each layer. The planetary mixer is stirred at a speed of 15 r / min for 15 min, and then the speed is increased to 60 r / min and stirred for 60 min, and vacuum is drawn while stirring;

[0089] (2) coating the first layer of slurry on one side of the glass fiber cloth using a coating machine;

[0090] (3) first apply the second layer of slurry on the other side of the fiberglass cloth, and then apply the third layer of slurry;

[0091] (4) After coating, bake in an oven at 150°C for 15 minutes.

[0092] The multifunctional silica gel gaskets of Examples 1 to 3 and Comparative Examples 1 to 4 were subjected to performance tests, and the results are shown in Table 1.

[0093] The density of the multifunctional silicone gasket was tested using an electronic specific gravity meter. The breakdown voltage was tested according to GB / T 19264.2-2013 Electrical pressboard and paperboard Part 2: Test methods. The dielectric constant was tested using a dielectric constant tester. The volume resistivity was tested using a rubber gasket resistivity tester. Thermal impedance and thermal conductivity were tested according to ASTM D5470-06 Chinese version Standard Test Method for Thermal Transfer Properties of Thermally Conductive Electrical Insulating Materials. The tensile strength and compression ratio were tested according to GB / T 1040.1-2006 Determination of Tensile Properties of Plastics Part 1: General. The hardness value was tested using a hardness tester. Flame retardancy was tested with reference to UL94 and the corresponding flame retardancy grade was determined. The absorption and shielding parameters were tested using an absorption and shielding test system.

[0094] Table 1 Performance test results of multifunctional silica gel gaskets of Examples 1 to 3 and Comparative Examples 1 to 4

[0095]

[0096] From the results in Table 1, it can be seen that the thermally conductive absorbing layer, the thermally conductive shielding layer and the thermally conductive insulating layer are composited on the glass fiber cloth, and the thermally conductive absorbing layer, the thermally conductive shielding layer and the thermally conductive insulating layer are all silicone layers containing different composite inorganic thermally conductive fillers. The prepared multifunctional silicone gasket not only has the characteristics of heat conduction, electromagnetic wave shielding, wave absorption and insulation, but also has a certain strength and can be used for buffering.

[0097] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention is described in detail with reference to the preferred embodiments, it is not limited to those listed in the embodiments. Those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A multifunctional silicone gasket, characterized in that: The invention comprises a heat-conducting absorbing layer, a glass fiber cloth, a heat-conducting shielding layer and a heat-conducting insulating layer which are stacked in sequence. The heat-conducting absorbing layer, the heat-conducting shielding layer and the heat-conducting insulating layer are all silicone layers containing composite inorganic heat-conducting fillers. The composite inorganic heat-conducting fillers in the heat-conducting absorbing layer contain aluminum oxide and carbonyl iron powder, the composite inorganic heat-conducting fillers in the heat-conducting shielding layer contain aluminum oxide and copper-plated nickel powder, and the composite inorganic heat-conducting fillers in the heat-conducting insulating layer contain boron nitride and aluminum oxide.

2. The multifunctional silicone gasket according to claim 1, characterized in that: The glass fiber cloth has a mesh size of 40 to 60 and a thickness of 0.01 to 0.03 mm.

3. The multifunctional silicone gasket according to claim 1, characterized in that: In parts by weight, the raw materials for preparing the thermal conductive wave absorbing layer include 7 to 15 parts of vinyl silicone oil, 0.1 to 0.5 parts of hydrogenated silicone oil, 0.01 to 0.05 parts of catalyst, 0.02 to 0.10 parts of silane coupling agent, 1 to 10 parts of aluminum oxide and 15 to 40 parts of carbonyl iron powder.

4. The multifunctional silicone gasket according to claim 1, characterized in that: The raw materials for preparing the thermal conductive shielding layer include, by weight, 7 to 15 parts of vinyl silicone oil, 0.1 to 0.5 parts of hydrogenated silicone oil, 0.01 to 0.05 parts of catalyst, 0.01 to 0.10 parts of color powder, 0.02 to 0.10 parts of silane coupling agent, 1 to 10 parts of aluminum oxide and 15 to 50 parts of copper-plated nickel powder.

5. The multifunctional silicone gasket according to claim 1, characterized in that: The raw materials for preparing the thermal conductive insulating layer include, by weight, 7 to 15 parts of vinyl silicone oil, 0.1 to 0.5 parts of hydrogenated silicone oil, 0.01 to 0.05 parts of catalyst, 0.01 to 0.10 parts of color powder, 0.02 to 0.10 parts of silane coupling agent, 5 to 25 parts of aluminum oxide and 1 to 15 parts of boron nitride.

6. The multifunctional silicone gasket according to any one of claims 3 to 5, characterized in that: The viscosity of the vinyl silicone oil at 25°C is 500-5000 mm 2 / s, vinyl content is 0.3~1.2%.

7. The multifunctional silicone gasket according to any one of claims 3 to 5, characterized in that: The catalyst includes at least one of H2PtCl6, [(CH2=CHSiMe2)2O]2Pt, (PPh3)2Pt-(CH2=CH2), (PPh3)3RhCl, Rh2(OAc)4, RhH(CO)(PPh3)3 and [Rh(COD)2]BF4-(PPh3)3.

8. The multifunctional silicone gasket according to any one of claims 3 to 5, characterized in that: The silane coupling agent includes at least one of A-150, A-151, A-171, A-172, KH-550, KH-560 and KH-570.

9. The multifunctional silicone gasket according to claim 4 or 5, characterized in that: The color powder includes at least one of golden C red, sun-fast brilliant red, sun-fast red, sun-fast dark red, permanent pink, permanent red, permanent red, bright red pink, lithocarmin, pigment ruby, magenta, permanent rose red, red lotus, sun-fast lotus color source, permanent purple, sun-fast yellow, permanent yellow, benzidine yellow, lemon yellow, medium chrome yellow, sun-fast orange, permanent orange, phthalocyanine blue, phthalocyanine green, ultramarine, art green, iron red, iron yellow and iron black.

10. The method for preparing the multifunctional silicone gasket according to any one of claims 1 to 9, characterized in that: Includes steps: (1) mixing the raw materials for preparing each layer of the heat conductive absorbing layer, the heat conductive shielding layer and the heat conductive insulating layer in a mixer to obtain slurry of each layer; (2) coating the slurry of the heat-conducting and wave-absorbing layer on one side of the glass fiber cloth; (3) first coating the slurry of the thermal conductive shielding layer on the other side of the glass fiber cloth, and then coating the slurry of the thermal conductive insulation layer; (4) Baking.

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