Automotive high-temperature-resistant organic silicon leather material and preparation method thereof

Abstract

The invention relates to a high-temperature-resistant organic silicon leather material for a vehicle and a preparation method thereof. The high-temperature-resistant organic silicon leather material for the vehicle comprises surface glue and primer. The surface adhesive is prepared from the following raw materials: high-temperature-resistant organic silicon resin, phenyl silicon resin, modified phenolic resin, a Si-H group-containing cross-linking agent, an organic solvent, an antioxidant, a heat stabilizer, an inhibitor, a platinum catalyst and filler. The primer is prepared from the following raw materials in parts by weight: high-temperature-resistant silica gel, an antioxidant, a heat stabilizer, an inhibitor, a platinum catalyst, filler, a Si-H group-containing cross-linking agent and an organic solvent. The automotive high-temperature-resistant organic silicon leather material prepared by the invention not only has basic excellent performance of conventional organic silicon leather, but also has the greatest advantage of high temperature resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of organic silicon leather, and specifically relates to a high temperature resistant organic silicon leather material for a vehicle and a preparation method thereof. Background Art

[0002] Globally, concerns about environmental protection and animal welfare are rapidly reshaping the leather industry - especially in China, the world's largest leather market. At the same time, both regular leather and current synthetic alternatives fail to meet the growing requirements of automotive and wearable electronics in terms of weather resistance, stain resistance, odor and sustainability. Regular leather is known for its soft touch and breathability, providing premium texture and comfort. However, it also has some obvious disadvantages, namely, it is not resistant to high temperatures.

[0003] Due to the need for automotive leather to be resistant to high temperatures, automotive leather sometimes not only needs to withstand long-term exposure to the outdoors and face high temperatures outdoors, but also needs to resist high temperatures from the engine. Therefore, if it is not resistant to high temperatures, it will reduce the service life of the leather and affect the physical properties of the leather.

[0004] The unique molecular structure of silicone can meet consumers' demands for leather in terms of softness, moisture permeability, stability and environmental friendliness. However, silicone leather is usually not resistant to high temperatures, which requires adding some high-temperature resistant components during the production process or improving the production method.

[0005] CN111519443A discloses an artificial leather that is resistant to high temperature, volatilization, low temperature, brittleness, and wiping, and a preparation method thereof. The leather prepared by the invention comprises the following components: polyvinyl chloride paste resin, trioctyl trimellitate, di(2-propylheptyl) adipate, stabilizer, and foaming agent. However, the high temperature resistant leather prepared by the method using PVC has poor mechanical properties, poor air permeability, and is difficult to maintain and clean. Summary of the invention

[0006] The technical problem to be solved by the present invention is that the organic silicon leather manufactured by the prior art is not very high temperature resistant, and the high temperature resistant organic silicon leather material for automobiles prepared by the present invention has a high maximum peeling load. The present invention manufactures a high temperature resistant organic silicon leather material by changing the raw materials, and also discloses a preparation method.

[0007] The present invention provides the following technical solutions:

[0008] A high temperature resistant organic silicon leather material for vehicles comprises a surface adhesive and a base adhesive.

[0009] The surface adhesive includes the following raw materials, measured in parts by weight: 5 to 20 parts of high temperature resistant silicone resin, 10 to 20 parts of phenyl silicone resin, 10 to 20 parts of modified phenolic resin, 2.5 to 5 parts of Si-H based crosslinking agent, 1 to 3 parts of organic solvent, 0.5 to 2.5 parts of antioxidant, 0.5 to 2.5 parts of heat stabilizer, 0.25 to 0.5 parts of inhibitor, 0.25 to 0.5 parts of platinum catalyst, and 4 to 8 parts of filler.

[0010] The primer includes the following raw materials, measured in parts by weight: 20 to 40 parts of high temperature resistant silicone, 0.5 to 2.5 parts of antioxidant, 0.5 to 2.5 parts of thermal stabilizer, 0.25 to 0.5 parts of inhibitor, 0.25 to 0.5 parts of platinum catalyst, 4 to 8 parts of filler, 2.5 to 5 parts of Si-H based crosslinking agent, and 1 to 5 parts of organic solvent.

[0011] The present invention also provides a method for preparing the high temperature resistant silica gel as follows, in parts by weight:

[0012] (1) 40 to 50 parts of methyl vinyl silicone rubber, 3 to 6 parts of hydroxy silicone oil with a hydroxyl content of 4 to 9%, 3 to 8 parts of dimethyldiethoxysilane as a silane coupling agent, and 1 to 3 parts of hydrogen silicone oil with a hydrogen content of 1.2 to 1.7% are stirred and kneaded for 5 to 10 minutes at a stirring speed of 300 to 500 rpm to obtain a mixture;

[0013] (2) 10 to 20 parts of a specific surface area of ​​200 to 400 m 2 / g fumed silica, 1-2 parts of zinc stearate and 20-30 parts of diatomaceous earth with a particle size of 1000-3000 mesh are mixed and added to the above (1) mixture, stirring while adding, the stirring speed is 500-600rpm, the stirring time is 20-30min, and vacuum kneading is continued to raise the temperature to 180-200°C, and the vacuum degree is adjusted to -0.09 to -0.1MPa. After stirring for 2-4h, the stirring speed is 500-600rpm, and after stirring and cooling to 40-50°C, 3-5 parts of a specific surface area of ​​50-200m 2 / g cerium oxide is stirred and kneaded for 30 to 50 minutes at a stirring speed of 300 to 500 rpm, and the material is discharged through a 200 to 400 mesh filter to obtain the high temperature resistant silica gel.

[0014] The present invention also discloses a method for preparing the high temperature resistant silicone resin:

[0015] The modifier and the silicone resin are mixed and stirred evenly in a mass ratio of 1:5 to 8, the stirring speed is 3000 to 4000 rpm, and the stirring time is 2 to 3 hours; the heat treatment is continued at 70 to 90°C for 1 to 2 hours to obtain a solidified product; the solidified product is dissolved and stirred with acetone, the stirring speed is 2500 to 3000 rpm, the stirring time is 30 to 60 minutes, and 1 to 3 g of activated bentonite is continued to be added, and the stirring is evenly stirred, the stirring speed is 10 to 20 minutes, and the stirring speed is 800 to 1000 rpm to obtain the high temperature resistant silicone resin.

[0016] The present invention also discloses a method for preparing the modifier:

[0017] S1: 103-128 g of methyltriethoxysilane, 10-12 g of deionized water and 6-8 g of anhydrous ethanol are mixed and stirred at a stirring speed of 1000-1500 rpm for 10-15 min;

[0018] S2: Add 1-1.5g of benzoyl peroxide to the mixture of S1, heat to 110-120°C, and continue stirring for 30-40min; then add 1-2g of coupling agent, adjust the temperature to 70-80°C, and keep warm for 2-3 hours; then drop 0.5-1.0g of dimethylacetamide and stir at a stirring speed of 800-1000rpm for 2-5min.

[0019] S3: The mixture obtained in S3 is subjected to ultrasonic treatment for 3 to 6 minutes, and then cooled naturally to room temperature to obtain the modifier.

[0020] Functions of each component of the modifier:

[0021] Methyltriethoxysilane: It contains hydrolyzable ethoxy groups and reactive methyl groups. Ethoxy groups will hydrolyze in water, releasing ethanol and forming silanol groups, which can further condense to form a cross-linked network structure, enhancing the heat resistance and mechanical properties of the resin. The methyl group gives the resin hydrophobicity and organic compatibility, improving its stability in non-polar media.

[0022] Anhydrous ethanol: Anhydrous ethanol mainly acts as a solvent, helping methyltriethoxysilane to disperse better and participate in its hydrolysis reaction, promoting its conversion into a more active form. At the same time, ethanol, as a reaction by-product, can be removed by evaporation in subsequent steps, which helps to adjust the viscosity and reaction conditions of the system.

[0023] Benzoyl peroxide: As a free radical initiator, benzoyl peroxide decomposes under heating conditions to produce free radicals, which can initiate polymerization or cross-linking reactions of methyltriethoxysilane or other unsaturated compounds, thereby accelerating the curing process of the resin and improving the cross-linking density and thermal stability of the modifier.

[0024] Coupling agent: The role of coupling agent here is to enhance the interfacial bonding between inorganic filler (bentonite) and silicone resin. It bridges the organic and inorganic phases through chemical action and improves the overall properties of the composite material, such as improving mechanical strength, heat resistance and anti-aging properties.

[0025] Dimethylacetamide: It has good solubility and low toxicity. On the one hand, as a solvent, it helps the components to mix evenly, especially for the components that are not easily soluble; on the other hand, its polar characteristics may promote certain chemical reactions, such as accelerating the reaction of coupling agents or promoting the interaction between other components, and ultimately optimizing the performance of the modifier. In addition, its use in the ultrasonic treatment step may help to further promote the reaction and the uniformity of the product through the mechanical effect and cavitation of ultrasound.

[0026] The coupling agent in step S2 is at least one of phenyltriethoxysilane, γ-glycidyloxypropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, and γ-mercaptopropyltrimethoxysilane; further preferably, the coupling agent in step S2 is phenyltriethoxysilane.

[0027] The phenyl silicone resin is at least one of SIC 6016, SIC 6168P, SIC 6103A, and SIC 1016; more preferably, the phenyl silicone resin is SIC 6168P.

[0028] The mass ratio of the high temperature resistant silicone resin, phenyl silicone resin and modified phenolic resin is 2-5:2-5:3-4; further preferably, the mass ratio of the high temperature resistant silicone resin, phenyl silicone resin and modified phenolic resin is 3:3:3.

[0029] The Si-H group-containing cross-linking agent is a polydimethylsiloxane having at least 3 hydrogen atoms directly connected to Si, the hydrogen atoms are located at the chain end or the side chain, and the hydrogen atom content is 0.3-2.1%; further preferably, the Si-H group-containing cross-linking agent is a polydimethylsiloxane having at least 3 hydrogen atoms directly connected to Si, the hydrogen atoms are located at the chain end or the side chain, and the hydrogen atom content is 0.8-1.5%.

[0030] The Si-H group-containing crosslinking agent used in the embodiment is hexamethyldisiloxane.

[0031] The antioxidant is at least one of BASF Irganox 245, CHIMASSORB 944, butylated hydroxytoluene and butylated hydroxyanisole; more preferably, the antioxidant is BASF Irganox 245.

[0032] The heat stabilizer is at least one of vinyl triethoxysilane, hydrogen-containing silicone oil, dibutyltin dilaurate, di-n-butyltin bis(monooctyl maleate), zinc borate, tri(nonylphenyl)phosphite, and epoxy alkyl phosphonate; further preferably, the heat stabilizer is di-n-butyltin bis(monooctyl maleate).

[0033] The platinum catalyst is at least one of chloroplatinic acid isopropanol solution, chloroplatinic acid tetrahydrofuran solution, chloroplatinic acid-divinyltetramethyldisiloxane complex, chloroplatinic acid-1,3,5,7-tetravinyl-1,3,5,7-tetramethyl-cyclotetrasiloxane, and chloroplatinic acid-divinyltetramethyldisiloxane; further preferably, the platinum catalyst is chloroplatinic acid isopropanol solution.

[0034] The inhibitor is at least one of 2-methyl-3-butyn-2-ol, ethynyl cyclohexanol, alkynyl-containing maleic acid, alkynyl-containing maleic acid derivatives, and polyvinyl polysiloxane. More preferably, the inhibitor is 2-methyl-3-butyn-2-ol.

[0035] The filler is at least one of fumed silica, ceramic powder, carbon fiber, matting powder, aluminum hydroxide, zinc borate, aluminum silicate, calcium carbonate, glass beads, barium sulfate, white carbon black, graphene, silicone resin powder, and magnesium oxide; more preferably, the filler is calcium carbonate.

[0036] The particle size of calcium carbonate used in the examples is 800 mesh.

[0037] The organic solvent is at least one of C1-C4 alkanes, C1-C4 aromatic hydrocarbons, C1-C4 ethers, C1-C4 esters, octamethylcyclotetrasiloxane and decamethylcyclopentasiloxane.

[0038] The organic solvent used in the example is octamethylcyclotetrasiloxane.

[0039] The methyl vinyl silicone rubber is at least one of MY 110, MY 112, and MY 120; further preferably, the methyl vinyl silicone rubber is MY 120.

[0040] The hydroxy silicone oil has a hydroxy content of 4 to 9%. More preferably, the hydroxy silicone oil has a hydroxy content of 5 to 9%.

[0041] The hydrogen content of the hydrogen-containing silicone oil is 1.2-1.7%; more preferably, the hydrogen content of the hydrogen-containing silicone oil is 1.5-1.7%.

[0042] The specific surface area of ​​the fumed silica is 200 to 400 m 2 / g; Further preferably, the specific surface area of ​​the fumed silica is 200 to 300 m 2 / g.

[0043] The diatomaceous earth particle size is 1000-3000 mesh, and more preferably, the diatomaceous earth particle size is 2000-3000 mesh.

[0044] The preparation method of the high temperature resistant silicone leather material for automobiles comprises the following preparation steps, calculated in parts by weight:

[0045] Step 1: 5 to 20 parts of high temperature resistant silicone resin, 10 to 20 parts of phenyl silicone resin, 10 to 20 parts of modified phenolic resin, 2.5 to 5 parts of Si-H-based crosslinking agent, 1.0 to 5.0 parts of organic solvent, 0.5 to 2.5 parts of antioxidant, 0.5 to 2.5 parts of heat stabilizer, 0.25 to 0.5 parts of inhibitor, 0.25 to 0.5 parts of platinum catalyst, and 4 to 8 parts of filler are mixed and stirred for 30 to 50 minutes at a stirring speed of 300 to 500 rpm to obtain a surface adhesive;

[0046] Step 2: Apply the adhesive obtained in step 1 on the release paper at a coating amount of 90-100 g / m 2 , continue heating and curing, the curing heating temperature is 80-160°C, the heating time is 3-10 minutes, and a cured surface layer adhesive is obtained;

[0047] Step 3: Mix and stir 20-40 parts of high temperature resistant silica gel, 0.5-2.5 parts of antioxidant, 0.5-2.5 parts of heat stabilizer, 0.25-0.5 parts of inhibitor, 0.25-0.5 parts of platinum catalyst, 4-8 parts of filler, 2.5-5 parts of Si-H-based crosslinking agent, and 1.0-5.0 parts of organic solvent for 30-50 minutes at a stirring speed of 300-500 rpm to obtain a primer;

[0048] Step 4: Apply the primer obtained in step 3 on the cured surface glue obtained in step 2 to form a primer layer. The coating amount is 90-100 g / m 2 , and then compounding the base adhesive layer with the anti-adhesive non-woven fabric of the base layer, heating and curing, the curing heating temperature is 80-160° C., the curing time is 3-10 minutes, and the release paper is peeled off to obtain the high temperature resistant silicone leather material for automobiles.

[0049] The functions of the main raw materials in the present invention are introduced as follows:

[0050] High temperature resistant silicone: provides the basic glue structure to form the base layer of leather.

[0051] High temperature resistant silicone resin: gives the material excellent properties such as high temperature resistance, weather resistance, chemical corrosion resistance and mechanical strength.

[0052] Phenyl silicone resin: Since phenyl can improve the heat resistance and hardness of silicone resin, adding phenyl silicone resin can enhance the high temperature resistance and mechanical properties of leather.

[0053] Modified phenolic resin: Generally not commonly used in silicone leather, it may be to add additional heat resistance or other specific properties, but it needs to be confirmed whether it is compatible with silicone-based materials and maintains the required performance.

[0054] Si-H-based crosslinking agent: used to achieve crosslinking and curing through the combined action of hydrogen bonds Si-H and Si-Vi to form a three-dimensional network structure and improve the strength and temperature resistance of the final product.

[0055] Antioxidant: Prevents materials from degrading due to oxidation at high temperatures or for long periods of time.

[0056] Thermal stabilizer: further enhances the stability of the material under high temperature conditions.

[0057] Platinum catalyst: catalyzes the addition reaction between the hydrogen-silicon bonds in silicone and vinyl siloxane, promoting the cross-linking curing process.

[0058] Inhibitors: Control the activity of platinum catalysts to avoid premature curing during storage and transportation.

[0059] Fillers: such as calcium carbonate, used to adjust cost, hardness, thickness and certain physical properties.

[0060] Organic solvent: acts as a carrier during the preparation process to help mix evenly, but should evaporate completely in the final product to ensure environmental protection requirements.

[0061] Beneficial effects of the present invention:

[0062] The automotive high temperature resistant organic silicon resin prepared by the present invention not only has the excellent performance of conventional resins, but also has high temperature resistance. DETAILED DESCRIPTION

[0063] In order to further understand the present invention, a high temperature resistant organic silicon leather material for automobile and a preparation method thereof provided by the present invention are described in detail below in conjunction with embodiments.

[0064] In the following statements:

[0065] Silicone resin, model: 9802, source: Hubei Longsheng Sihai New Materials Co., Ltd.

[0066] Phenyl silicone resin, model: SIC 6168P, brand: SIC.

[0067] Modified phenolic resin, homemade, preparation method reference "Qian Chunxiang, Zhao Hongkai, Xiong Youming et al. Thermal Performance Analysis of Nano-TiO2 Particle Modified Boron Phenolic Resin [J]. Functional Materials, 2006, 37 (7): 1114-1117"; the specific preparation method is as follows: add 1mL 27%wt ammonia water to 50g phenol, stir while adding, the stirring speed is 300rpm, continue to heat to 60℃, continue to add 35mL 35%wt formaldehyde aqueous solution, continue to heat to 90℃, continue to add 1g nano titanium dioxide and react at constant temperature for 20min; continue to add 10mL 35%wt formaldehyde aqueous solution, react at constant temperature for 80min, continue to add 1g boric acid and react at constant temperature for 100min; then decompress and dehydrate under 60kPa, 60℃ conditions; at 160℃, quickly discharge the prepared resin when the gel time reaches 90s.

[0068] Nano titanium dioxide, with an average particle size of 5 nm, comes from Zhejiang Zhoushan Mingri Nanomaterials Co., Ltd.

[0069] Di(octyl maleate) di-n-butyltin, CAS number: 33568-99-9.

[0070] 2-Methyl-3-butyn-2-ol, CAS number: 115-19-5.

[0071] The chloroplatinic acid isopropanol solution was prepared in-house, and the preparation method was as follows: 40.9 g of chloroplatinic acid solid was dissolved in 1.0 L of 79% wt isopropanol aqueous solution to prepare a 5% wt chloroplatinic acid isopropanol solution.

[0072] Calcium carbonate, particle size 800 mesh.

[0073] Activated bentonite, model: TY-138C, source: Anji Tianyu Bentonite Co., Ltd.

[0074] Anti-stick non-woven fabric, brand: Yiqingke, model: dry net, item number: 4106, source: Hangzhou Yiqing Filter Material Co., Ltd.

[0075] Methyl vinyl silicone rubber, model: MY 120, source: Anhui Mingyi Silicon Industry Co., Ltd.

[0076] The hydroxyl content is 8% hydroxy silicone oil, sourced from Shandong Longhui Chemical Co., Ltd.

[0077] The hydrogen content is 1.5% hydrogen-containing silicone oil, sourced from Shandong Longhui Chemical Co., Ltd.

[0078] Example 1

[0079] A method for preparing a high temperature resistant silicone leather material for a vehicle is as follows:

[0080] Step 1: 12g of high temperature resistant silicone resin, 12g of phenyl silicone resin, 12g of modified phenolic resin, 2.5g of Si-H crosslinking agent hexamethyldisiloxane, 3g of organic solvent octamethylcyclotetrasiloxane, 1.5g of antioxidant BASF Irganox245, 1.5g of heat stabilizer di(maleic acid monooctyl ester) di-n-butyltin, 0.25g of inhibitor 2-methyl-3-butyn-2-ol, 0.25g of platinum catalyst chloroplatinic acid isopropanol solution, and 5g of filler calcium carbonate are stirred for 40min at a stirring speed of 500rpm to obtain a surface adhesive;

[0081] Step 2: Apply the adhesive obtained in step 1 on the release paper with a coating amount of 100g / m 2 , continue heating and curing, the curing heating temperature is 110°C, the heating time is 8 minutes, and a cured surface layer adhesive is obtained;

[0082] Step 3: 26g of high temperature resistant silica gel, 1.5g of antioxidant BASF Irganox 245, 1.5g of heat stabilizer di(monooctyl maleate) di-n-butyltin, 0.25g of inhibitor 2-methyl-3-butyn-2-ol, 0.25g of platinum catalyst chloroplatinic acid isopropanol solution, 5g of filler calcium carbonate, 2.5g of Si-H-containing crosslinking agent hexamethyldisiloxane, and 3g of organic solvent octamethylcyclotetrasiloxane were mixed and stirred for 40min at a stirring speed of 500rpm to obtain a primer;

[0083] Step 4: Apply the primer obtained in step 3 above on the cured surface glue obtained in step 2 to form a primer layer. The coating amount is 90g / m 2 , and then compound the base adhesive layer and the anti-adhesive non-woven fabric of the base layer together, heat and cure, the curing heating temperature is 110° C., the curing time is 8 minutes, and the release paper is peeled off to obtain the high temperature resistant silicone leather material for the vehicle.

[0084] The preparation steps of the high temperature resistant silica gel in the above step 3 are as follows:

[0085] (1) 44 g of methyl vinyl silicone rubber, 5 g of hydroxy silicone oil with a hydroxyl content of 8%, 6 g of dimethyldiethoxysilane as a silane coupling agent, and 3 g of hydrogen silicone oil with a hydrogen content of 1.5% were stirred and kneaded for 10 min at a stirring speed of 500 rpm to obtain a mixture;

[0086] (2) 15g of a specific surface area of ​​300m 2 / g fumed silica, 2g zinc stearate and 20g diatomaceous earth with a particle size of 2000 mesh were mixed and added to the above (1) mixture, stirring while adding, the stirring speed was 600rpm, the stirring time was 30min, and vacuum kneading was continued to raise the temperature to 180°C, the vacuum degree was adjusted to -0.1MPa, and after stirring for 3h, the stirring speed was 600rpm, and after stirring and cooling to 50°C, 5g of a specific surface area of ​​100m 2 / g cerium oxide was stirred and kneaded for 40 minutes at a stirring speed of 500 rpm, and the material was discharged through a 200-mesh filter to obtain the high-temperature resistant silica gel.

[0087] The preparation method of the high temperature resistant silicone resin is as follows:

[0088] The modifier and the silicone resin are mixed and stirred evenly in a mass ratio of 1:5, with a stirring speed of 3000 rpm and a stirring time of 2 hours; the heat treatment is continued at 80°C for 2 hours to obtain a solidified product; the solidified product is dissolved and stirred with 300 mL of acetone, with a stirring speed of 3000 rpm and a stirring time of 30 minutes, and 1 g of activated bentonite is continued to be added, stirred evenly, with a stirring speed of 10 minutes and a stirring speed of 1000 rpm to obtain the high temperature resistant silicone resin.

[0089] The preparation method of the modifier is as follows:

[0090] 128g of methyltriethoxysilane, 12g of deionized water and 8g of anhydrous ethanol were mixed and stirred at a stirring speed of 1500rpm for 15min; then 1.5g of benzoyl peroxide was added, heated to 120°C, and stirring was continued for 30min; then 1g of coupling agent phenyltriethoxysilane was added, the temperature was adjusted to 70°C, and kept warm for 2 hours; then 0.5g of dimethylacetamide was dripped in and stirred at a stirring speed of 800rpm for 3min, ultrasonic treatment was continued for 6min, and then naturally cooled to room temperature to obtain a modifier.

[0091] Example 2

[0092] A method for preparing a high temperature resistant silicone leather material for a vehicle is as follows:

[0093] Step 1: 10.8 g of high temperature resistant silicone resin, 10.8 g of phenyl silicone resin, 14.4 g of modified phenolic resin, 2.5 g of Si-H crosslinking agent hexamethyldisiloxane, 3 g of organic solvent octamethylcyclotetrasiloxane, 1.5 g of antioxidant BASF Irganox 245, 1.5 g of heat stabilizer di(maleic acid monooctyl ester) di-n-butyltin, 0.25 g of inhibitor 2-methyl-3-butyn-2-ol, 0.25 g of platinum catalyst chloroplatinic acid isopropanol solution, and 5 g of filler calcium carbonate are stirred for 40 min at a stirring speed of 500 rpm to obtain a surface adhesive;

[0094] Step 2: Apply the adhesive obtained in step 1 on the release paper with a coating amount of 100g / m 2 , continue heating and curing, the curing heating temperature is 110°C, the heating time is 8 minutes, and a cured surface layer adhesive is obtained;

[0095] Step 3: 26 g of high temperature resistant silica gel, 1.5 g of antioxidant BASF Irganox 245, 1.5 g of heat stabilizer di(monooctyl maleate) di-n-butyltin, 0.25 g of inhibitor 2-methyl-3-butyn-2-ol, 0.25 g of platinum catalyst chloroplatinic acid isopropanol solution, 5 g of filler calcium carbonate, 2.5 g of Si-H-containing crosslinking agent hexamethyldisiloxane, and 3 g of organic solvent octamethylcyclotetrasiloxane were mixed and stirred for 40 min at a stirring speed of 500 rpm to obtain a primer;

[0096] Step 4: Apply the primer obtained in step 3 on the cured surface glue obtained in step 2 to form a primer layer. The coating amount is 90g / m 2 , and then compound the base adhesive layer and the anti-adhesive non-woven fabric of the base layer together, heat and cure, the curing heating temperature is 110° C., the curing time is 8 minutes, and the release paper is peeled off to obtain the high temperature resistant silicone leather material for the vehicle.

[0097] The preparation method of the high temperature resistant organic silicone resin and high temperature resistant silica gel is the same as that in Example 1 and will not be repeated here.

[0098] Example 3

[0099] A method for preparing a high temperature resistant silicone leather material for a vehicle is as follows:

[0100] Step 1: 7.2g of high temperature resistant silicone resin, 10.8g of phenyl silicone resin, 18g of modified phenolic resin, 2.5g of Si-H crosslinking agent hexamethyldisiloxane, 3g of organic solvent octamethylcyclotetrasiloxane, 1.5g of antioxidant BASF Irganox245, 1.5g of heat stabilizer di(maleic acid monooctyl ester) di-n-butyltin, 0.25g of inhibitor 2-methyl-3-butyn-2-ol, 0.25g of platinum catalyst chloroplatinic acid isopropanol solution, and 5g of filler calcium carbonate are stirred for 40min at a stirring speed of 500rpm to obtain a surface adhesive;

[0101] Step 2: Apply the adhesive obtained in step 1 on the release paper with a coating amount of 100g / m 2 , continue heating and curing, the curing heating temperature is 110°C, the heating time is 8 minutes, and a cured surface layer adhesive is obtained;

[0102] Step 3: 26 g of high temperature resistant silica gel, 1.5 g of antioxidant BASF Irganox 245, 1.5 g of heat stabilizer di(monooctyl maleate) di-n-butyltin, 0.25 g of inhibitor 2-methyl-3-butyn-2-ol, 0.25 g of platinum catalyst chloroplatinic acid isopropanol solution, 5 g of filler calcium carbonate, 2.5 g of Si-H-containing crosslinking agent hexamethyldisiloxane, and 3 g of organic solvent octamethylcyclotetrasiloxane were mixed and stirred for 40 min at a stirring speed of 500 rpm to obtain a primer;

[0103] Step 4: Apply the primer obtained in step 3 on the cured surface glue obtained in step 2 to form a primer layer. The coating amount is 90g / m 2 , and then compound the base adhesive layer and the anti-adhesive non-woven fabric of the base layer together, heat and cure, the curing heating temperature is 110° C., the curing time is 8 minutes, and the release paper is peeled off to obtain the high temperature resistant silicone leather material for the vehicle.

[0104] The preparation method of the high temperature resistant organic silicone resin and high temperature resistant silica gel is the same as that in Example 1 and will not be repeated here.

[0105] Example 4

[0106] The only difference between Example 4 and Example 1 is that the coupling agent used in the preparation process of the high temperature resistant silicone resin modifier is different, and γ-glycidyloxypropyltrimethoxysilane is used instead of phenyltriethoxysilane.

[0107] Example 5

[0108] The only difference between Example 5 and Example 1 is that a different coupling agent is used in the preparation process of the silicone resin modifier, and N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane is used instead of phenyltriethoxysilane.

[0109] Example 6

[0110] The only difference between Example 6 and Example 1 is that the coupling agent used in the preparation process of the silicone resin modifier is different, and γ-mercaptopropyltrimethoxysilane is used instead of phenyltriethoxysilane.

[0111] Comparative Example 1

[0112] A method for preparing a high temperature resistant silicone leather material for a vehicle is as follows:

[0113] Step 1: 18g of high temperature resistant silicone resin, 18g of phenyl silicone resin, 2.5g of Si-H crosslinking agent hexamethyldisiloxane, 3g of organic solvent octamethylcyclotetrasiloxane, 1.5g of antioxidant BASF Irganox 245, 1.5g of heat stabilizer di(maleic acid monooctyl) di-n-butyltin, 0.25g of inhibitor 2-methyl-3-butyn-2-ol, 0.25g of platinum catalyst chloroplatinic acid isopropanol solution, and 5g of filler calcium carbonate are stirred for 40min at a stirring speed of 500rpm to obtain a surface adhesive;

[0114] Step 2: Apply the adhesive obtained in step 1 on the release paper with a coating amount of 100g / m 2 , continue heating and curing, the curing heating temperature is 110°C, the heating time is 8 minutes, and a cured surface layer adhesive is obtained;

[0115] Step 3: 26 g of high temperature resistant silica gel, 1.5 g of antioxidant BASF Irganox 245, 1.5 g of heat stabilizer di(monooctyl maleate) di-n-butyltin, 0.25 g of inhibitor 2-methyl-3-butyn-2-ol, 0.25 g of platinum catalyst chloroplatinic acid isopropanol solution, 5 g of filler calcium carbonate, 2.5 g of Si-H-containing crosslinking agent hexamethyldisiloxane, and 3 g of organic solvent octamethylcyclotetrasiloxane were mixed and stirred for 40 min at a stirring speed of 500 rpm to obtain a primer;

[0116] Step 4: Apply the primer obtained in step 3 on the cured surface glue obtained in step 2 to form a primer layer. The coating amount is 90g / m 2 , and then compound the base adhesive layer and the anti-adhesive non-woven fabric of the base layer together, heat and cure, the curing heating temperature is 110° C., the curing time is 8 minutes, and the release paper is peeled off to obtain the high temperature resistant silicone leather material for the vehicle.

[0117] The preparation method of the high temperature resistant organic silicone resin and high temperature resistant silica gel is consistent with that in Embodiment 1 and will not be described in detail here.

[0118] Test Example 1: Test on the high temperature resistance of the high temperature resistant silicone leather material for automobiles prepared in the examples and comparative examples

[0119] The automotive high temperature resistant organic silicon leather materials prepared in the above-mentioned embodiments and comparative examples were subjected to high temperature tests respectively, and then the elongation at break / % and tensile strength / MPa thereof were measured to examine their high temperature resistance.

[0120] High temperature test: stand at 200℃ for 20h;

[0121] The elongation at break / % and tensile strength / MPa tests were conducted in accordance with the GB / T 38612-2020 method, and the average value of three tests was taken. The actual test results show the changes in the elongation at break and tensile strength before and after the high temperature test, as well as the elongation at break and tensile strength after the high temperature test;

[0122] Table 1 High temperature resistance test results of high temperature resistant silicone leather materials for vehicles prepared in Examples and Comparative Examples

[0123]

[0124]

[0125] It can be seen from Table 1 above that the automotive high temperature resistant organic silicon leather material prepared in Example 1 has the best high temperature resistance.

[0126] Comparing Examples 1-3, it can be seen that different compounding ratios of high-temperature resistant silicone resin, phenyl silicone resin, and modified phenolic resin will also affect the high-temperature resistance of automotive high-temperature resistant silicone leather materials. The possible reasons are: 1. Differences in chemical structure and thermal stability: High-temperature resistant silicone resin provides excellent high-temperature resistance and oxidation resistance with its unique silicon-oxygen bond as the main chain. The introduction of phenyl in phenyl silicone resin further enhances the heat resistance and light stability of the material. Modified phenolic resin has a higher thermal decomposition temperature, and its structure contains a strong conjugated system, which can enhance the high-temperature resistance of the material to a certain extent; 2. Cross-linking density and network structure: The interaction between different resins and the cross-linking method will affect the cross-linking density and network structure integrity of the final leather material, thereby affecting the thermal stability of the material. High-temperature resistant silicone resin and phenyl silicone resin can form different cross-linking networks through different cross-linking agents, and modified phenolic resin may participate in the cross-linking reaction after blending to form a more complex network structure; 3. Synergistic effect and complementary performance: The appropriate proportion of compounding can give full play to the performance advantages of various resins, form a synergistic effect, and improve the overall high-temperature resistance. If the ratio is not appropriate, the advantages of a certain resin may not be fully utilized, or some of the performance may be offset, reducing the overall heat resistance; 4. Thermal expansion coefficient and mechanical properties: Various resins have different thermal expansion coefficients. Changes in the compounding ratio will affect the thermal expansion properties of the final material, thereby affecting the dimensional stability and mechanical properties at high temperatures.

[0127] By comparing Example 1 and Examples 4-6, it can be seen that the selection of coupling agent will also affect the high temperature resistance of the high temperature resistant silicone leather material for automobiles. The possible reasons are: 1. Chemical structure of coupling agent: The phenyltriethoxysilane used in Example 1 contains a benzene ring structure. The presence of the benzene ring can increase the thermal stability of the material because the benzene ring has a higher bond dissociation energy, which makes it more stable in the molecular structure under high temperature environment, thereby improving the high temperature resistance of the material. In contrast, although the coupling agents used in Examples 4-6 are all functionalized silicone coupling agents, their side chain structures are different. For example, the γ-glycidyloxypropyltrimethoxysilane in Example 4 mainly provides epoxy groups, the N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane in Example 5 contains amino functional groups, and the γ-mercaptopropyltrimethoxysilane in Example 6 contains mercapto groups. While these groups improve the adhesion or reaction activity between the material and other substrates, they may not be as effective as benzene rings in improving the thermal stability of the material itself; 2. Reactivity of coupling agents with silicone resins: Phenyltriethoxysilane can better cross-link with silicone resins at high temperatures to form a tighter and more stable network structure, which is crucial for improving high temperature resistance. Although other coupling agents can also react with silicone resins, the thermal stability of the chemical bonds formed after the reaction may not be as stable as the benzene ring structure formed by phenylsilane; 3. The contribution of coupling agents to the thermal oxidation stability of materials: The benzene ring structure has good antioxidant properties at high temperatures, which can reduce the generation of free radicals and delay the thermal oxidation degradation process of materials in high temperature environments, thereby improving high temperature resistance; 4. The effect of coupling agents on the overall performance of materials: The functional groups introduced by different coupling agents may have different degrees of influence on the overall performance of the material (such as mechanical properties, aging resistance, etc.). These factors indirectly affect the performance of the material under high temperature conditions.

[0128] Comparing Example 1 with Comparative Example 1, although the modified phenolic resin is resistant to high temperatures, and its own high temperature resistance is helpful to the high temperature resistant silicone leather material for vehicles, the high temperature resistant silicone leather material for vehicles prepared by the present invention has significant high temperature resistance, indicating that the high temperature resistance of the high temperature resistant silicone leather material for vehicles prepared by the present invention is significantly improved compared with the modified phenolic resin.

[0129] Test Example 2: Peeling performance test of the high temperature resistant silicone leather material for automobile prepared in the embodiment and comparative example

[0130] Test method: according to the provisions of GB / T 8949-2008, cut three small leather samples of 150mm×30mm, use appropriate amount of adhesive to stick the coating with the same leather coating together (the sample must be firmly bonded), and then place the bonded samples at 135℃±5℃ for 2h, then peel the bonded samples by hand, separate the coating and base fabric of the sample to 50mm, and then clamp the separated ends on the fixture of the tensile testing machine, peel at a speed of 200mm / min, and record the maximum load of the sample peeling.

[0131] Evaluation criteria: When the maximum load of the sample is ≥18N, it is considered to meet the use requirements.

[0132] Table 2 Peeling performance test results of high temperature resistant silicone leather materials for automobiles

[0133] Maximum load / N Example 1 41 Example 2 31 Example 3 32 Example 4 24 Example 5 25 Example 6 23 Comparative Example 1 18

[0134] It can be seen from Table 2 above that the automotive high temperature resistant silicone leather material prepared in Example 1 has the largest maximum peeling load and the best quality; the leather material described in Comparative Example 1 has the smallest maximum peeling load and the worst quality.

[0135] Comparative Examples 1-3, the reasons for the different maximum peeling loads may be: 1. Complementary mechanical properties: High temperature resistant silicone resins are known for their excellent high temperature resistance, weather resistance and elasticity, and they give the material good flexibility and resilience. Phenyl silicone resin contains a benzene ring structure, which enhances the hardness, thermal stability and adhesion of the material to the pigment and substrate. Modified phenolic resin may provide high heat resistance and high strength properties, especially maintaining good mechanical properties under high temperature conditions; 2. Cross-linked network structure: The chemical structure differences between different resins determine that they form different cross-linked network structures during the curing process. Different compounding ratios will change the cross-linking density and the distribution of cross-linking bonds, thereby affecting the overall strength and peeling resistance of the material. Phenyl silicone resin and high temperature resistant silicone resin interact through various modes of action such as hydrogen bonds and van der Waals forces to increase peel strength; and modified phenolic resin may participate in the cross-linking reaction through its unique functional groups to form a tighter three-dimensional structure; 3. Compatibility and compatibility: The compatibility between various resins directly affects the uniformity and interfacial bonding of the final material. When the ratio is properly matched, the resins can fuse better, reducing defects and interface stress concentration, thereby improving peel strength; 4. Matching thermal expansion coefficients: Different resins have different thermal expansion coefficients. The appropriate ratio can optimize the thermal expansion and contraction performance and avoid peeling damage caused by thermal stress.

[0136] Comparing Example 1 with Examples 4-6, the reasons for the different maximum peeling loads may be: 1. Differences in the coupling agent structure: Phenyltriethoxysilane (Example 1) contains a phenyl group, and the benzene ring structure has a larger conjugated system, which can improve the thermal stability and rigidity of the material to a certain extent, and is conducive to forming a more stable cross-linked structure, thereby improving the heat resistance and peel strength of the material. γ-Glycidyloxypropyltrimethoxysilane (Example 4) is mainly used to improve the adhesion to substrates such as epoxy resins, but due to its short side chain, it may provide a relatively small enhancement effect when forming a cross-linked network. N-β-(Aminoethyl)-γ-aminopropylmethyldimethoxysilane (Example 5) has an amino active group, which is suitable for reacting with materials containing active hydrogen to enhance the bonding performance, but in the high temperature resistant silicone leather material system, its effect on improving the peel strength may not be as obvious as phenyltriethoxysilane. The mercapto group (-SH) of γ-mercaptopropyltrimethoxysilane (Example 6) can form a stronger chemical bond, but it may not be very stable in a high temperature environment, which may lead to a decrease in the peeling load; 2. Compatibility with high temperature resistant silicone resin: Different coupling agents have different compatibilities with high temperature resistant silicone resin, which will affect the uniformity and interfacial bonding properties of the final material. Phenyltriethoxysilane has better compatibility with high temperature resistant silicone resin due to its benzene ring structure, and the interface layer formed is more solid, so it may bring a higher peeling load; 3. Adhesion performance with the substrate: One of the main functions of the coupling agent is to improve the adhesion between the high temperature resistant silicone resin and the leather substrate or other fillers. Due to its unique chemical structure, phenyltriethoxysilane may be easier to penetrate into the surface of the substrate and form a stronger chemical bond, thereby improving the peeling strength; 4. Cross-linking efficiency: Different coupling agents have different abilities to participate in the cross-linking reaction. Phenyltriethoxysilane may have a higher cross-linking efficiency, forming a denser and more stable cross-linking network, thereby increasing the maximum peeling load of the leather material.

[0137] Comparing Example 1 with Comparative Example 1, the reasons for the difference in maximum peeling load may be: 1. Enhanced mechanical properties: Phenolic resin itself has high mechanical strength and heat resistance, and the modified phenolic resin can further improve these properties. In leather materials, phenolic resin can form a cross-linked network with high-temperature resistant silicone resin and other resins to strengthen the overall structure of the material, thereby increasing the peeling load of the leather material; 2. Thermal stability and high temperature resistance: Modified phenolic resin often has excellent high temperature resistance. Its addition can improve the stability of high-temperature resistant silicone leather materials under high temperature conditions, prevent structural relaxation and performance degradation caused by high temperature, and indirectly ensure that the material can still maintain a high peeling strength in a high temperature environment; 3. Interface bonding: Modified phenolic resin can produce a good interface bonding effect with high-temperature resistant silicone resin and other components through its chemical structure, and enhance the interaction between the components, which is crucial to increasing the peeling load. If the modified phenolic resin is missing, effective bonding may not be formed between the layers inside the leather material, resulting in a significant reduction in the peeling load; 4. Filler dispersion and loading: Modified phenolic resin may also help to disperse and load fillers such as calcium carbonate and carbon black. The presence of fillers can enhance the mechanical properties of the composite material, and the addition of modified phenolic resin may be beneficial to the uniform distribution of these fillers in the resin matrix, effectively transferring stress, thereby increasing the maximum peeling load of the material.

[0138] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Modifications, replacements, and improvements made within the principles of the present invention should all be included in the protection scope of the present invention.

Claims

1. A method for preparing a high temperature resistant silicone leather material for a vehicle, comprising the following steps: Step 1: 5-20 parts of high temperature resistant silicone resin, 10-20 parts of phenyl silicone resin, 10-20 parts of modified phenolic resin, 2.5-5 parts of Si-H-based crosslinking agent, 1-5 parts of organic solvent, 0.5-2.5 parts of antioxidant, 0.5-2.5 parts of heat stabilizer, 0.25-0.5 parts of inhibitor, 0.25-0.5 parts of platinum catalyst, and 4-8 parts of filler are mixed and stirred for 30-50 minutes at a stirring speed of 300-500 rpm to obtain a surface adhesive; Step 2: Apply the adhesive obtained in step 1 on the release paper at a coating amount of 90-100 g / m 2 , continue heating and curing, the curing heating temperature is 80-160°C, the heating time is 3-10 minutes, and a cured surface layer adhesive is obtained; Step 3: Mix and stir 20-40 parts of high temperature resistant silica gel, 0.5-2.5 parts of antioxidant, 0.5-2.5 parts of heat stabilizer, 0.25-0.5 parts of inhibitor, 0.25-0.5 parts of platinum catalyst, 4-8 parts of filler, 2.5-5 parts of Si-H-based crosslinking agent, and 1-5 parts of organic solvent for 30-50 minutes at a stirring speed of 300-500 rpm to obtain a primer; Step 4: Apply the primer obtained in step 3 on the cured surface glue obtained in step 2 to form a primer layer. The coating amount is 80-90 g / m 2 , continue to compound the base glue layer and the anti-adhesive non-woven fabric of the base layer, heat and cure, the curing heating temperature is 80 to 160° C., the curing time is 3 to 10 minutes, and the release paper is peeled off to obtain the high temperature resistant silicone leather material for automobiles; The above parts are all parts by weight.

2. The method for preparing a high temperature resistant silicone leather material for a vehicle according to claim 1, characterized in that: The preparation method of the high temperature resistant silicone resin is as follows: the modifier and the silicone resin are mixed and stirred evenly in a mass ratio of 1:5 to 8, the stirring speed is 3000 to 4000 rpm, and the stirring time is 2 to 3 hours; the heat preservation treatment is continued at 70 to 90°C for 1 to 2 hours to obtain a solidified product; the solidified product is dissolved and stirred with 200 to 500 mL of acetone, the stirring speed is 2500 to 3000 rpm, the stirring time is 30 to 60 minutes, and 1 to 3 g of activated bentonite is continuously added, and the stirring is evenly stirred at a stirring speed of 10 to 20 minutes, and the stirring speed is 800 to 1000 rpm to obtain the high temperature resistant silicone resin.

3. The method for preparing a high temperature resistant silicone leather material for a vehicle according to claim 2, characterized in that: Preparation of the modifier: S1: 103-128 g of methyltriethoxysilane, 10-12 g of water and 6-8 g of anhydrous ethanol are mixed and stirred at a stirring speed of 1000-1500 rpm for 10-15 min; S2: Add 1-1.5 g of benzoyl peroxide to the mixture obtained in step S1 above, heat to 110-120° C., and continue stirring for 30-40 min; then add 1-2 g of coupling agent, adjust the temperature to 70-80° C., and keep warm for 2-3 hours; then dropwise add 0.5-1.0 g of dimethylacetamide and stir at a stirring speed of 800-1000 rpm for 2-5 min; S3: The mixture obtained in the above step S2 is subjected to ultrasonic treatment for 3 to 6 minutes, and then cooled naturally to room temperature to obtain the modifier.

4. The method for preparing the high temperature resistant silicone leather material for automobile according to claim 3, characterized in that: The coupling agent is at least one of phenyltriethoxysilane, γ-glycidyloxypropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane and γ-mercaptopropyltrimethoxysilane.

5. The method for preparing the high temperature resistant silicone leather material for automobile according to claim 1, characterized in that: The phenyl silicone resin is at least one of SIC 6016, SIC 6168P, SIC 6103A, and SIC 1016.

6. The method for preparing the high temperature resistant silicone leather material for automobile according to claim 1, characterized in that: The mass ratio of the high temperature resistant organic silicon resin, the phenyl silicon resin and the modified phenolic resin is 2-5:2-5:3-4.

7. The method for preparing the high temperature resistant silicone leather material for automobile according to claim 1, characterized in that: The Si-H group-containing crosslinking agent is a polydimethylsiloxane having at least three hydrogen atoms directly connected to Si, wherein the hydrogen atoms are located at the chain end or the side chain, and the content of the hydrogen atoms is 0.3-2.1%; the antioxidant is at least one of BASF Irganox 245, CHIMASSORB 944, butylated hydroxytoluene, and butylated hydroxyanisole; the heat stabilizer is at least one of vinyl triethoxysilane, hydrogen-containing silicone oil, dibutyltin dilaurate, di(monooctyl maleate) di-n-butyltin, zinc borate, tri(nonylphenyl)phosphite, and epoxyalkylphosphonate; the platinum catalyst is at least one of chloroplatinic acid isopropanol solution, chloroplatinic acid tetrahydrofuran solution, chloroplatinic acid-divinyltetramethyldisiloxane complex, chloroplatinic acid-1,3,5,7-tetravinyl-1,3,5,7-tetramethyl-cyclotetrasiloxane, and chloroplatinic acid-divinyltetramethyldisiloxane.

8. The method for preparing the high temperature resistant organic silicon leather material for vehicles according to claim 1, characterized in that: The inhibitor is at least one of 2-methyl-3-butyn-2-ol, ethynyl cyclohexanol, alkynyl-containing maleic acid, alkynyl-containing maleic acid derivatives, and polyvinyl polysiloxane.

9. The method for preparing the high temperature resistant silicone leather material for automobile according to claim 1, characterized in that: The filler is at least one of fumed silica, ceramic powder, carbon fiber, matting powder, aluminum hydroxide, zinc borate, aluminum silicate, calcium carbonate, glass microspheres, barium sulfate, white carbon black, graphene, silicone resin micropowder, and magnesium oxide; the organic solvent is at least one of C1-C2 alkanes, C1-C2 aromatics, C1-C2 ethers, C1-C2 esters, octamethylcyclotetrasiloxane, and decamethylcyclopentasiloxane.

10. A high temperature resistant silicone leather material for automobiles, characterized in that: Prepared by the method according to any one of claims 1 to 9.

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