Silicone rubber foam material and preparation method thereof

Abstract

The invention relates to the technical field of foaming materials, and particularly discloses a silicone rubber foaming material and a preparation method thereof. The silicone rubber foaming material is prepared from the following raw materials in parts by weight: 1-60 parts of hydroxyl silicone oil, 10-60 parts of vinyl silicone oil, 1-15 parts of hydrogen-containing silicone oil, 1-5 parts of methyl silicone oil, 0.5-1 part of an inhibitor, 0.25-0.5 part of a platinum catalyst, 5-15 parts of modified polysiloxane and 10-30 parts of white carbon black. The invention also provides a preparation method of the composition. Compared with the prior art, the silicone rubber foaming material prepared by the invention does not contain halogen and other harmful substances, does not cause secondary pollution in a combustion process, and can realize efficient balance of mechanical properties and flame retardant properties.

Description

Technical Field

[0001] The present invention relates to the technical field of foaming materials, in particular to a silicone rubber foaming material and a preparation method thereof. Background Art

[0002] Silicone rubber, scientifically known as organosiloxane, is a key member of the organosilicon compound family. Silicone rubber with a silicon-oxygen bond (Si-O) as its backbone accounts for over 90% of the total. The side chains of this type of rubber are typically connected to functional groups such as hydroxyl, methyl, vinyl, and phenyl groups. The unique structure of the Si-O bond imparts its exceptional properties, with a longer bond length and higher bond energy than a CC bond. This difference makes compounds with Si-O bonds as their backbone far superior to their CC counterparts in terms of high and low temperature resistance, electrical insulation, and aging resistance.

[0003] Silicone rubber foam achieves a cross-functional fusion of performance, combining the inherently superior properties of silicone rubber, such as high- and low-temperature stability, aging resistance, electrical insulation, and radiation resistance, with the unique elasticity, lightweight, and shock-absorbing properties of the foam. In the aerospace sector, it is widely used for filling wings and cabins, as well as for thermal insulation in key fuselage areas. Its excellent shock-absorbing properties make it an ideal choice for the manufacture of vehicles like automobiles and high-speed rail. In the industrial sector, its thermal insulation properties make it suitable for use in equipment such as cables and pipelines. It is worth noting that when this material is thermally decomposed, it only produces small molecules such as SiO2, CO2, and H2O. It is completely non-toxic and pollution-free, making it a model of a new environmentally friendly material.

[0004] Currently, silicone rubber foam materials on the market are primarily categorized into two main types: kneaded silicone rubber and liquid silicone rubber. Liquid silicone rubber, also known as room temperature vulcanized silicone rubber foam, uses a base of siloxanes with a low to medium degree of polymerization. This is mixed with a crosslinker, a foaming agent, reinforcing fillers, and other functional additives to create a low-viscosity, self-flowing compound. This compound can be directly extruded or injection molded without complex processing, significantly improving production efficiency and ease of use.

[0005] Patent CN107141806A discloses a kind of intrinsic flame-retardant silicone rubber foam material and its preparation method and application.The raw materials for preparing the silicone rubber foam material include brominated modified silicone oil, foaming agent, reinforcing agent, catalyst and crosslinking agent.The preparation process is as follows: first, brominated modification is carried out on the silicone oil by means of silicone oil modification system to obtain brominated modified silicone oil; then, the brominated modified silicone oil is mixed with the foaming agent, reinforcing agent, catalyst and crosslinking agent to prepare the silicone rubber foam material.The preparation method is simple, and the modified silicone oil contains halogen elements, so the material itself has flame retardance without the need for additional flame retardant.The use of heat treatment foaming technology makes the foaming process easy to control, and the prepared material has high foaming ratio, high strength, good elasticity and excellent flame retardance.

[0006] Patent CN118546530A proposes a kind of high flame-retardant fire-resistant silicone rubber foam material for building fireproof plugging and its preparation method.The material is made of specific weight fractions of raw materials: 100 parts of silicone rubber foam foaming component, 30-50 parts of flame-retardant ceramicized polyborosiloxane aerogel powder, 20-40 parts of fire-resistant filler and 5-20 parts of flame retardant.The flame-retardant ceramicized polyborosiloxane aerogel powder is prepared from organosiloxane (vinylsiloxane and epoxy siloxane, with a molar ratio of 1:1-1:5), boric acid or its derivative, curing agent, fluxing agent and solvent.This invention improves the comprehensive performance of silicone rubber foam, including flame retardance, fire resistance, mechanical properties and thermal insulation performance, successfully solves the problem of affecting the foaming and vulcanization process of silicone rubber foam after the introduction of common fluxing agents, and prepares a silicone rubber foam material with high flame retardance and fire resistance.

[0007] Silicone rubber foam has excellent flame retardance due to the inorganic siloxane backbone, which is a non-flammable component, compared to other polymer materials, and is often used as a sealing material.However, the organic groups contained in the side chain of silicone rubber foam are flammable components, and the foam itself has numerous pores with a large contact area with air, so relying solely on the non-flammable components in the inorganic siloxane backbone to achieve flame retardance cannot meet the application requirements.At present, flame retardants are mainly added to improve the flame retardance of silicone rubber foam.However, traditional flame retardant fillers such as magnesium hydroxide and aluminum hydroxide need to be added in large quantities to be effective, which not only easily causes agglomeration, but also damages the mechanical properties of the material, and has a negative impact on the foaming process. SUMMARY

[0008] In view of the above-mentioned defects of the prior art, the technical problem to be solved by the present application is to provide a silicone rubber foaming material and a preparation method thereof.

[0009] In order to solve the balance between the flame retardant performance and the mechanical property of the silicone rubber foam material, the application provides a modified polysiloxane, the modified polysiloxane is introduced with B-O, B-B and Si-O-B bonds, and the B-O bond, as a dynamic covalent bond, shows stronger electronic defects and higher electronegativity because they have more valence orbitals. At the same time, the B-O bond forms a dynamic crosslinking network in the silicone rubber foam material, so that the material has better elasticity and shape recovery ability. The reversibility of the B-O dynamic coordination bond is enhanced by the synergistic coordination of boron, and the energy is consumed by the fracture-recombination under stress. The boron in the Si-O-B bond can generate boric acid and boric oxide at high temperature, capture active free radicals (such as ·OH and ·H) in the combustion process, interrupt the combustion chain reaction, and form a protective layer by ceramicization at high temperature. In addition, boron catalyzes the dehydration crosslinking of siloxane chains in the silicone rubber matrix to accelerate the formation of Si-O-Si network and thus play a synergistic flame retardant effect, thereby achieving high-efficiency flame retardation.

[0010] The application introduces the flame-retardant component by chemical crosslinking instead of physical blending, and the silicone rubber foam material is prepared by preparing the modified polysiloxane and polymerizing with hydroxyl silicone oil, hydrogen-containing silicone oil and other components, so that the flame-retardant performance is improved without causing the decrease of the mechanical property. In order to achieve the above purpose, the application provides a silicone rubber foam material, which is prepared from the following raw materials by weight: 1-60 parts of hydroxyl silicone oil, 10-60 parts of vinyl silicone oil, 1-15 parts of hydrogen-containing silicone oil, 1-5 parts of methyl silicone oil, 0.5-1 part of inhibitor, 0.25-0.5 part of platinum catalyst, 5-15 parts of modified polysiloxane and 10-30 parts of white carbon black.

[0011] The preparation method of the modified polysiloxane comprises the following steps: The vinyl monomer and tetrahydroxy diboron are added into 30wt% ethanol aqueous solution, and the pH is adjusted to 3-4 by adding acid, then stirred at room temperature for 10-14h, and then stirred at elevated temperature for 4-8h, and the modified polysiloxane is obtained by distillation and drying after the reaction is completed.

[0012] Further, the vinyl monomer is one of vinyl trimethoxysilane, vinyl dimethylethoxysilane and vinyl phenyl methyl methoxysilane.

[0013] Further, the mass ratio of the vinyl monomer, tetrahydroxy diboron and ethanol aqueous solution is 1:0.04-0.08:1-3.

[0014] Preferably, the preparation method of the modified polysiloxane comprises the following steps: Vinyl monomer and tetrahydroxy diboron are added into 30wt% ethanol aqueous solution, the mass ratio of vinyl monomer, tetrahydroxy diboron, and ethanol aqueous solution is 1:0.04-0.08:1-3, after adding acid to adjust pH to 3-4, stirring at room temperature for 10-14h, then heating to 85-95℃ and stirring for 4-8h, after the reaction is completed, distillation under reduced pressure, drying to obtain modified polysiloxane.

[0015] Further, the hydroxyl silicone oil is a small molecular weight hydroxyl silicone oil, and the viscosity is 5000-10000 Pa·s.

[0016] Further, the viscosity of the vinyl silicone oil is 10000 Pa·s.

[0017] Further, the hydrogen content of the hydrogen-containing silicone oil is 0.1-2%.

[0018] Further, the viscosity of the methyl silicone oil is 500 Pa·s.

[0019] Further, the inhibitor is an addition type inhibitor.

[0020] Further, the content of the platinum catalyst Pt is 3000 ppm.

[0021] A preparation method of a silicone foam material, comprising the following steps: S1, mixing the hydroxyl silicone oil and white carbon black according to the proportion, and stirring with the remaining components for 10-20min at a speed of 1000r / min; S2, preheating the mixture in a mold at 90-100℃ for 5-10min to foam; S3, after curing at 140-160℃ for 5-10min, cooling, and demolding, the silicone rubber foam material is obtained.

[0022] The beneficial effects of the present application are: 1. Compared with the prior art, the present application introduces a flame-retardant component by chemical crosslinking, which improves the flame-retardant performance without causing a decrease in mechanical properties.

[0023] 2. The present application introduces B-B and Si-O-B bonds in the silicone rubber, the B-O bond forms a dynamic crosslinking network in the silicone rubber foam material, and the double boron cooperates to enhance the reversibility of the B-O dynamic coordination bond, which breaks and recombines under stress to consume energy, thereby making the material have better elasticity and shape recovery ability. Boron in the Si-O-B bond can generate boric acid and boric oxide at high temperature, capture active free radicals (such as ·OH, ·H) in the combustion process, interrupt the combustion chain reaction, and also form a protective layer by ceramicization at high temperature. In addition, boron catalyzes the dehydration crosslinking of siloxane chains in the silicone rubber matrix to accelerate the formation of Si-O-Si network, thereby playing a synergistic flame-retardant effect, and achieving high-efficiency flame retardation. DETAILED DESCRIPTION

[0024] Tetrahydroxydiboron, CAS No.: 13675-18-8.

[0025] Vinylphenylmethylmethoxysilane, CAS No.: 80252-60-4.

[0026] Hydroxyl silicone oil, 8000 Pa·s, Model No. 107, from Dow Corning.

[0027] White carbon black, Catalog No. A200, from WACKER, Germany.

[0028] Vinyl silicone oil, 10000 Pa·s, Model No. JP-01V, from Shenzhen Jipeng Silicon Fluoride Material Co., Ltd.

[0029] Hydrosilicone oil, hydrogen content 1.5%, Model No. JP-202, from Shenzhen Jipeng Silicon Fluoride Material Co., Ltd.

[0030] Methyl silicone oil, 500 Pa·s, Model No. 201, from Dow Corning.

[0031] Platinum gold catalyst, 3000 ppm, Catalog No. XH-PT, from Shenzhen Jipeng Silicon Fluoride Material Co., Ltd.

[0032] Example 1 A preparation method of a silicone foam material, comprising the following steps, in terms of weight parts: S1, mixing hydroxyl silicone oil 5 parts and white carbon black 30 parts, and then stirring together with vinyl silicone oil 60 parts, hydrosilicone oil 15 parts, methyl silicone oil 2 parts, modified polysiloxane 10 parts, ethynylcyclohexanol 0.5 parts, and platinum gold catalyst 0.25 parts for 15 min at a speed of 1000 r / min; S2, preheating the mixture in a mold at 100℃ for 10 min to foam; S3, after curing at 150℃ for 10 min, cooling, and then demolding, a silicone rubber foam material is obtained.

[0033] The preparation method of the modified polysiloxane comprises the following steps: Vinyltrimethoxysilane and tetrahydroxydiboron are added to a 30 wt% ethanol aqueous solution, the mass ratio of the vinyltrimethoxysilane, tetrahydroxydiboron, and the ethanol aqueous solution is 1:0.065:2, after adjusting the pH to 3.5 by adding acetic acid, stirring at room temperature for 12 h, and then stirring at 90℃ for 6 h, the modified polysiloxane is obtained after distillation and drying under reduced pressure.

[0034] Example 2 A preparation method of a silicone foam material, comprising the following steps, in terms of weight parts: S1, 5 parts of hydroxyl silicone oil and 30 parts of white carbon black were mixed and then stirred with 60 parts of vinyl silicone oil, 15 parts of hydrogen-containing silicone oil, 2 parts of methyl silicone oil, 10 parts of modified polysiloxane, 0.5 parts of ethynyl cyclohexanol and 0.25 parts of platinum catalyst for 15 min at a speed of 1000 r / min; S2, the mixture was loaded into a mold and preheated at 100℃ for 10 min; S3, after curing at 150℃ for 10 min, the mold was removed after cooling to obtain a silicone rubber foaming material.

[0035] The preparation method of the modified polysiloxane comprises the following steps: Vinyl dimethyl ethoxy silane and tetrahydroxy diboron were added to a 30wt% ethanol aqueous solution, the mass ratio of vinyl dimethyl ethoxy silane, tetrahydroxy diboron and the ethanol aqueous solution was 1:0.065:2, acetic acid was added to adjust the pH to 3.5, then stirred at room temperature for 12 h, then heated to 90℃ and stirred for 6 h, after the reaction was completed, vacuum distillation and drying were performed to obtain the modified polysiloxane.

[0036] Example 3 A preparation method of a silica gel foaming material, comprising the following steps, in terms of weight parts: S1, 5 parts of hydroxyl silicone oil and 30 parts of white carbon black were mixed and then stirred with 60 parts of vinyl silicone oil, 15 parts of hydrogen-containing silicone oil, 2 parts of methyl silicone oil, 10 parts of modified polysiloxane, 0.5 parts of ethynyl cyclohexanol and 0.25 parts of platinum catalyst for 15 min at a speed of 1000 r / min; S2, the mixture was loaded into a mold and preheated at 100℃ for 10 min; S3, after curing at 150℃ for 10 min, the mold was removed after cooling to obtain a silicone rubber foaming material.

[0037] The preparation method of the modified polysiloxane comprises the following steps: Vinyl dimethyl ethoxy silane and tetrahydroxy diboron were added to a 30wt% ethanol aqueous solution, the mass ratio of vinyl dimethyl ethoxy silane, tetrahydroxy diboron and the ethanol aqueous solution was 1:0.065:2, acetic acid was added to adjust the pH to 3.5, then stirred at room temperature for 12 h, then heated to 90℃ and stirred for 6 h, after the reaction was completed, vacuum distillation and drying were performed to obtain the modified polysiloxane.

[0038] Comparative Example 1 A preparation method of a silica gel foaming material, comprising the following steps, in terms of weight parts: S1, 5 parts of hydroxyl silicone oil and 30 parts of white carbon black were mixed and then stirred with 60 parts of vinyl silicone oil, 15 parts of hydrogen-containing silicone oil, 2 parts of methyl silicone oil, 10 parts of modified polysiloxane, 0.5 parts of ethynyl cyclohexanol and 0.25 parts of platinum catalyst for 15 min at a speed of 1000 r / min; S2, the mixture is loaded into the mold 100℃ preheating foaming 10 min; S3, after curing at 150℃ for 10 min, cooling and demolding to obtain the silicone rubber foaming material.

[0039] Comparative Example 2 A preparation method of a silicone rubber foaming material, comprising the following steps, in parts by weight: S1, after mixing hydroxyl silicone oil 5 parts and white carbon black 30 parts, stirring with vinyl silicone oil 60 parts, hydrogen-containing silicone oil 15 parts, methyl silicone oil 2 parts, magnesium hydroxide 10 parts, acetylene cyclohexanol 0.5 parts, platinum catalyst 0.25 parts for 15 min, the speed is 1000 r / min; S2, the mixture is loaded into the mold 100℃ preheating foaming 10 min; S3, after curing at 150℃ for 10 min, cooling and demolding to obtain the silicone rubber foaming material.

[0040] Comparative Example 3 A preparation method of a silicone rubber foaming material, comprising the following steps, in parts by weight: S1, after mixing hydroxyl silicone oil 5 parts and white carbon black 30 parts, stirring with vinyl silicone oil 60 parts, hydrogen-containing silicone oil 15 parts, methyl silicone oil 2 parts, magnesium hydroxide 40 parts, acetylene cyclohexanol 0.5 parts, platinum catalyst 0.25 parts for 15 min, the speed is 1000 r / min; S2, the mixture is loaded into the mold 100℃ preheating foaming 10 min; S3, after curing at 150℃ for 10 min, cooling and demolding to obtain the silicone rubber foaming material.

[0041] Comparative Example 4 A preparation method of a silicone rubber foaming material, comprising the following steps, in parts by weight: S1, after mixing hydroxyl silicone oil 5 parts and white carbon black 30 parts, stirring with vinyl silicone oil 60 parts, hydrogen-containing silicone oil 15 parts, methyl silicone oil 2 parts, modified polysiloxane 10 parts, acetylene cyclohexanol 0.5 parts, platinum catalyst 0.25 parts for 15 min, the speed is 1000 r / min; S2, the mixture is loaded into the mold 100℃ preheating foaming 10 min; S3, after curing at 150℃ for 10 min, cooling and demolding to obtain the silicone rubber foaming material.

[0042] The preparation method of the modified polysiloxane, comprising the following steps: Vinyl trimethoxysilane and boric acid were added into 30wt% aqueous ethanol solution, the mass ratio of vinyl trimethoxysilane, boric acid and aqueous ethanol solution was 1:0.065:2, after adding acetic acid to adjust the pH to 3.5, stirring at room temperature for 12h, then heating to 90℃ and stirring for 6h, after the reaction was completed, vacuum distillation and drying to obtain modified polysiloxane.

[0043] Test Example 1 The tensile strength and elongation at break of the silicone rubber foamed materials prepared in the examples and the control example were tested according to GB / T 528-2009 “Determination of tensile stress-strain properties of vulcanized or thermoplastic rubbers”, and the compression performance was tested according to GB / T 7759-2015 “Determination of compression set of vulcanized or thermoplastic rubbers”.

[0044] Tensile strength is used to determine the maximum stress that a material can withstand before it breaks under tension. The test uses a standard dumbbell-shaped specimen that is clamped in the grips of a tensile testing machine and subjected to continuous, uniform tension until it breaks. Tensile strength is calculated by dividing the maximum force recorded during the test (F m ) by the original cross-sectional area of the specimen (A0), TS = Fm / A0. Elongation at break is used to determine the percentage (%) of elongation of a material relative to its original length at the point of tensile failure. The test uses the same dumbbell-shaped specimen, temperature conditions, and rate of extension as the tensile strength test. The original gauge length (L0) is marked on the specimen before testing. During the test, the tensile testing machine continuously stretches the specimen until it breaks. When the specimen breaks, the distance between the two marks at the instant of break (L u ) is measured. Elongation at break (Eb) = [(L u -L0) / L0] x 100%.

[0045] The test method for compression set is to prepare a standard cylindrical or ring-shaped specimen, measure the original thickness (h0), place the specimen in the grips and compress it to a specified deformation rate using a limiter, at which time the thickness is h1; place it in a constant temperature environment for a specified time, immediately unload after taking it out, and recover for 30 minutes; measure the final thickness (h2), and calculate the result according to the formula K (%) = [(h0-h2) / (h0-h1)] x 100%.

[0046] Table 1

[0047] The present application adopts high-viscosity vinyl silicone oil to provide base skeleton strength, hydrogen-containing silicone oil to provide controllable cross-linking density, and white carbon black as a filler to improve dimensional stability, so that the prepared silicone rubber foam material has strength in a medium-low load interval, but can provide high deformation tolerance and good compressibility, and is suitable for the field of electronic packaging which requires sealing, light weight, and high deformation.

[0048] As can be seen from Table 1, the mechanical properties and compression properties of the examples are better than those of the control examples. In the control examples, magnesium hydroxide is added as a flame retardant. However, in order to reduce the combustion temperature, magnesium hydroxide needs to absorb a large amount of heat. However, the heat release rate of the silicone rubber foam is fast during combustion, and the heat absorption capacity per unit mass is limited. Therefore, a high amount of magnesium hydroxide must be added to offset the heat. However, the small particle size and large specific surface area of magnesium hydroxide result in poor compatibility between the polar surface and the non-polar silicone rubber. A large amount of magnesium hydroxide will cause serious agglomeration, forming stress concentration points and accelerating material fracture. Therefore, the mechanical properties of the control example 3 are the worst. In the examples, the flame-retardant component is introduced by chemical cross-linking instead of physical blending through modified polysiloxane and hydrogen-containing silicone oil, which improves the flame-retardant properties without causing a decrease in mechanical properties. The B atom has a lack of electrons, and forms a reversible coordination bond with the oxygen atom. The bond breaks / recombines under stress, achieving energy absorption. The reversible B-O dynamic coordination bond is enhanced by the synergistic coordination of the two boron atoms. Therefore, the stress can be better released during stretching, thereby improving the mechanical and compression properties. Compared with examples 1-2, example 3 uses a vinyl monomer containing a phenyl group, which increases the supportability of the cell structure after foaming. Therefore, the overall tensile resistance and resilience are better, and the mechanical properties and compression properties are better. Compared with control example 4, the four-hydroxy diboron in example 1 makes the modified polysiloxane also have a B-B bond. The reason why the tensile resistance and compression deformation capacity of example 1 are better may be that the reversible B-O dynamic coordination bond is enhanced by the synergistic coordination of the two boron atoms, which breaks and recombines under stress to consume energy and avoid permanent sliding of the molecular chain, so that the overall performance of the sample of example 1 is better.

[0049] Test Example 2 The silicone rubber foam materials prepared in the examples and the control examples were tested for flame retardant properties and limiting oxygen index according to GB / T 10707-2008 “Determination of Combustion Behavior of Rubber”. The flame retardant properties were tested by vertical combustion method. The standard size rubber sample (130 mm x 13 mm x 3 mm) was vertically fixed on the support, and the lower end was aligned with the flame nozzle. The center of the lower end of the sample was ignited with a methane flame for 10 seconds, and the flaming combustion time (t1) was recorded after the flame was removed. After the flaming combustion stopped, the sample was ignited again for 10 seconds, and the second flaming combustion time (t2) and the flameless combustion time (t3) were recorded after the flame was removed. Finally, according to the total combustion time (t1+t2), whether the molten droplets ignited the cotton below, and other behaviors, the flame retardant properties were determined according to the FV-0, FV-1, FV-2 grades.

[0050] Limiting Oxygen Index (LOI) test refers to GB / T 2406.1-2008 "Plastics - Determination of the burning behavior in an oxygen environment - Part 1: Guidance", standard sample (100mm x 8mm x 6mm) is vertically fixed at the top of the transparent combustion cylinder, and oxygen-nitrogen mixed gas with a preset oxygen concentration is passed at a constant flow rate; the top end of the sample is ignited with an igniter, and the burning behavior is observed (if the continuous burning is ≥3min or the burning length is ≥50mm, it is determined to be successful); the minimum oxygen volume percentage required for the sample to maintain flaming combustion in the nitrogen-oxygen mixed gas is determined, which is the limiting oxygen index (LOI).

[0051] Table 2

[0052] It can be found by comparing the examples and the comparative examples that a large amount of magnesium hydroxide needs to be added to achieve good flame-retardant effect, while the modified polysiloxane in the examples can achieve good flame-retardant effect even without a large amount of addition, which is because the Si-O-B bond and boron in the B-O bond can generate boric acid and boric oxide at high temperature, capture active free radicals (such as ·OH and ·H) in the combustion process, and interrupt the combustion chain reaction. In addition, boron can catalyze the dehydration and crosslinking of siloxane chains in the silicone rubber matrix, accelerate the formation of Si-O-Si network, and thus play a synergistic flame-retardant effect, thereby achieving high-efficiency flame retardation. The vinyl monomer in Example 3 has better high-temperature resistance and better flame-retardant effect due to the high-thermal-stability phenyl group.

[0053] The above describes the preferred embodiments of the present application in detail. It should be understood that those skilled in the art can make many modifications and changes without creative labor based on the concept of the present application. Therefore, any technical solution obtained by logical analysis, reasoning or limited experiment based on the prior art according to the concept of the present application shall be within the protection scope defined by the claims.

Claims

1. A silicone rubber foam material, characterized in that: The invention is prepared from the following raw materials in parts by weight: 1-60 parts of hydroxy silicone oil, 10-60 parts of vinyl silicone oil, 1-15 parts of hydrogenated silicone oil, 1-5 parts of methyl silicone oil, 0.5-1 parts of inhibitor, 0.25-0.5 parts of platinum catalyst, 5-15 parts of modified polysiloxane and 10-30 parts of white carbon black.

2. The silicone rubber foam material according to claim 1, wherein The preparation method of the modified polysiloxane comprises the following steps: The vinyl monomer and tetrahydroxydiboron were added to a 30 wt% ethanol aqueous solution, and the pH was adjusted to 3-4 by adding acid. The mixture was stirred at room temperature for 10-14 hours, and then heated and stirred for 4-8 hours. After the reaction was completed, the modified polysiloxane was obtained by vacuum distillation and drying.

3. The silicone rubber foam material according to claim 2, wherein: The vinyl monomer is one of vinyl trimethoxy silane, vinyl dimethyl ethoxy silane or vinyl phenyl methyl methoxy silane.

4. The silicone rubber foam material according to claim 2, wherein: The mass ratio of the vinyl monomer to tetrahydroxydiboron and the ethanol aqueous solution is 1:0.04-0.08:1-3.

5. The silicone rubber foam material according to claim 1, wherein The hydroxy silicone oil is a small molecular weight hydroxy silicone oil with a viscosity of 5000-10000 Pa·s.

6. The silicone rubber foam material according to claim 1, wherein: The viscosity of the vinyl silicone oil is 10000 Pa·s.

7. The silicone rubber foam material according to claim 1, wherein The hydrogen content of the hydrogen-containing silicone oil is 0.1-2%.

8. The silicone rubber foam material according to claim 1, wherein The viscosity of the methyl silicone oil is 500 Pa·s.

9. The silicone rubber foam material according to claim 1, wherein: The inhibitor is an addition-type inhibitor; the Pt content of the platinum catalyst is 3000 ppm.

10. The method for preparing the silicone rubber foam material according to any one of claims 1 to 9, wherein: The steps include: S1. Mix hydroxy silicone oil and white carbon black in proportion and stir with the remaining components for 10-20 minutes at a speed of 1000 r / min; S2. Place the mixed material into a mold and preheat at 90-100°C for 5-10 minutes; S3. Curing at 140-160°C for 5-10 minutes, cooling, and demoulding to obtain the silicone rubber foam material.

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