High and low temperature resistant self-adhesive foamed leather and preparation method thereof

Abstract

This invention relates to the field of polymer materials technology, specifically disclosing a high- and low-temperature resistant self-adhesive foamed leather and its preparation method. The foamed leather is composed of a base fabric layer, a foamed layer, a self-adhesive layer, and a release layer, layered from top to bottom. Both the foamed layer and the self-adhesive layer utilize an organosilicon system with similar chemical properties, achieving interpenetrating cross-linking between the layers to form an integrated structure. The winding and curing process ensures full cross-linking of the self-adhesive layer, resulting in more stable adhesion and stronger interlayer bonding, preventing interlayer peeling or adhesion attenuation during use. Through process optimization, the product performance is controllable and suitable for industrialization. Using conventional polymer processing equipment, it is suitable for large-scale industrial production and is environmentally friendly. The prepared product possesses properties such as high and low temperature resistance, self-adhesion, cushioning, and decoration, and can be widely used in extreme high and low temperature environments such as automotive interiors, showing broad application prospects.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, specifically to a self-adhesive foamed leather resistant to high and low temperatures and its preparation method. Background Technology

[0002] Self-adhesive leather, as a functional composite material, is widely used in automotive interiors and electronic device protection due to its ease of use and the fact that it requires no additional adhesive. On the other hand, foamed leather, with its microporous structure, possesses excellent elasticity, cushioning, soft touch, and decorative properties, making it a promising candidate for use in automotive interiors where comfort is paramount.

[0003] Currently, the foamed leather used in automotive interiors is mainly polyurethane (PU) foamed leather or polyvinyl chloride (PVC) artificial leather. Its polymer chain structure determines its narrow temperature resistance range. However, foamed leather used in automotive interiors needs to withstand extreme temperatures from low winter temperatures to intense summer sun exposure. Polyurethane foamed leather has advantages such as low raw material cost, mature processing technology, and strong decorative properties, but it is prone to softening and deformation at high temperatures and hardening, becoming brittle, and even cracking at low temperatures. Polyvinyl chloride artificial leather, on the other hand, suffers from plasticizer migration issues and is prone to volatilization and aging at high temperatures. These defects seriously affect the reliability and service life of foamed leather in the automotive field.

[0004] Chinese patent CN118065150A discloses a low-temperature resistant PVC artificial leather, comprising a PVC leather layer and a base fabric layer, which are bonded together by a PVC adhesive layer. This PVC artificial leather exhibits excellent low-temperature resistant properties, but lacks self-adhesive functionality, and the high-temperature resistance of PVC material remains poor, easily volatilizing at high temperatures. Chinese patent application CN108797147A discloses a high-temperature resistant PU artificial leather, comprising a surface layer, an intermediate layer, and a bottom layer. The surface layer is composed of polyurethane resin, aluminum dihydrogen phosphate, alumina, bentonite, toughening agent, coupling agent, accelerator, and antistatic agent. The intermediate layer is composed of polyurethane foaming resin, heavy calcium carbonate, and a foaming agent. This PU artificial leather exhibits excellent high-temperature resistance, but lacks self-adhesive functionality and has poor low-temperature resistance.

[0005] Therefore, developing a soft and elastic foamed leather that can withstand harsh high and low temperature environments while maintaining stable self-adhesive properties is of great practical significance. Summary of the Invention

[0006] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides a high- and low-temperature resistant self-adhesive foamed leather and its preparation method, which solves the problem of poor high- and low-temperature resistance of traditional foamed leather, while also having a convenient self-adhesive function.

[0007] (II) Technical Solution To achieve the above objectives, the present invention discloses a self-adhesive foamed leather resistant to high and low temperatures, which comprises, from top to bottom, a base fabric layer, a foamed layer, a self-adhesive layer, and a release layer; The foamed layer is formed by dehydrogenation foaming of organosilicon and has a density of 0.3~0.6 g / cm³. 3 The pore diameter is 50~200μm; The self-adhesive layer is an organic silicone adhesive with a thickness of 10~50μm; The release layer is a fluororesin release film with a thickness of 20~100μm.

[0008] As a further aspect of the present invention: the surface of the base fabric layer is treated with a brushing process, and the thickness of the base fabric layer is 0.1~1.0mm, including any one of knitted fabric, woven fabric, non-woven fabric, artificial leather, and animal leather.

[0009] As a further aspect of the present invention: the foamed layer comprises the following raw materials in parts by weight: 100 parts of hydroxyl-terminated polydimethylsiloxane, 1-10 parts of hydrogen-containing silicone oil, 0.01-0.5 parts of platinum catalyst, 0.001-0.1 parts of inhibitor, and 5-8 parts of modified filler.

[0010] As a further aspect of the present invention: the inhibitor in the foaming layer is tetramethyltetravinylcyclotetrasiloxane.

[0011] As a further aspect of the present invention, the method for preparing the modified filler in the foamed layer includes the following steps: S1. Graphene oxide was ultrasonically dispersed in N,N-dimethylformamide. After uniform dispersion, maleic anhydride was added, stirred and mixed, heated, and reacted. After the reaction was completed, the mixture was washed with anhydrous ethanol, freeze-dried, and ground to obtain modified graphene oxide. S2. Mix the ethanol solution and 3-aminopropyltriethoxysilane evenly, adjust the pH to 4-5 with acetic acid, add hollow glass microspheres, stir and mix to allow the reaction to occur. After the reaction is complete, filter, wash with deionized water and anhydrous ethanol, and dry to obtain modified hollow glass microspheres. S3. N,N-dimethylformamide, modified graphene oxide, modified hollow glass microspheres, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, 1-hydroxybenzotriazole, and triethylamine are stirred and mixed, heated, and reacted. After the reaction is completed, the mixture is filtered, washed with anhydrous ethanol, and dried to obtain the modified filler.

[0012] As a further aspect of the present invention: the mass ratio of graphene oxide, N,N-dimethylformamide and maleic anhydride in S1 is 100:(18000~21000):(3000~3500).

[0013] As a further aspect of the present invention: the reaction temperature in S1 is 80~90℃, and the reaction time is 2~3h.

[0014] As a further aspect of the present invention: the mass ratio of ethanol solution, 3-aminopropyltriethoxysilane and hollow glass microspheres in S2 is (1500~1800):(32~50):100.

[0015] As a further aspect of the present invention: the reaction temperature in S2 is 60~70℃, and the reaction time is 4~6h.

[0016] As a further embodiment of the present invention: the mass ratio of N,N-dimethylformamide, modified graphene oxide, modified hollow glass microspheres, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, 1-hydroxybenzotriazole and triethylamine in S3 is (2100~2500):(25~48):100:(21~30):(12~15):(58~95).

[0017] As a further aspect of the present invention: the reaction temperature in S3 is 25~35℃, and the reaction time is 6~9h.

[0018] As a further aspect of the present invention: the self-adhesive layer comprises the following raw materials in parts by weight: 100 parts of vinyl polydimethylsiloxane, 3-15 parts of hydrogen-containing silicone oil, 20-60 parts of MQ silicone resin, 0.01-0.1 parts of platinum catalyst, and 0.001-0.05 parts of inhibitor.

[0019] As a further aspect of the present invention: the inhibitor in the self-adhesive layer is tetramethyltetravinylcyclotetrasiloxane.

[0020] As a further aspect of the present invention: the release layer is a fluoropolymer release film, wherein the fluoropolymer is selected from at least one of polytetrafluoroethylene, polyvinylidene fluoride, and fluorosilicone resin.

[0021] A method for preparing the high and low temperature resistant self-adhesive foamed leather includes the following steps: Step 1: After the base fabric layer is roughened, hydroxyl-terminated polydimethylsiloxane and modified filler are mixed evenly, hydrogen-containing silicone oil, platinum catalyst and inhibitor are added, and coated on the base fabric layer. The mixture is then foamed and cured at 80~120℃ to form a foamed layer, thus obtaining a base fabric layer-foamed layer composite preform. Step 2: Mix vinyl polydimethylsiloxane and MQ silicone resin evenly, add hydrogen-containing silicone oil, platinum catalyst and inhibitor, mix to obtain self-adhesive paste, coat the self-adhesive paste on the surface of the foam layer, and cure at 80~120℃ to form a self-adhesive layer, thus obtaining a composite preform of base fabric layer-foam layer-self-adhesive layer. Step 3: Apply fluoropolymer release film to the surface of the self-adhesive layer, press and bond it with the self-adhesive layer to form a release layer, and then roll it up and cure it. The curing temperature is 25~35℃ and the curing time is 72~96h to obtain self-adhesive foamed leather that is resistant to high and low temperatures.

[0022] As a further aspect of the present invention: the stirring speed for foaming in step one is 1000~3000 rpm, and the time is 60~120s.

[0023] As a further aspect of the present invention: before coating, the base fabric layer in step one is roughened to increase the roughness and specific surface area of ​​the contact surface, so that the foam layer can better penetrate and integrate. The coating method is either scraping or roller coating.

[0024] As a further aspect of the present invention: in step one, when the foam layer is semi-cured, it can also be given a certain micro-texture structure by embossing roller, and then combined with the self-adhesive layer to increase the effective contact area.

[0025] As a further aspect of the present invention: in the process of preparing the self-adhesive layer in step two, the coating method of the self-adhesive layer is either scraping or roller coating.

[0026] (iii) Beneficial technical effects Compared with the prior art, the beneficial effects of the present invention are as follows: (1) Both the foamed layer and the self-adhesive layer in this invention adopt an organosilicon system, which can effectively improve the heat resistance and cold resistance of the material. The foamed layer is prepared by dehydrogenation foaming of organosilicon. Organosilicon material itself has excellent heat resistance and cold resistance and can maintain elasticity over a wide temperature range, so that the foamed layer does not become brittle or decompose under extreme temperatures. The modified filler in the foamed layer is significantly improved in terms of strength, toughness and thermal stability through composite modification of graphene oxide and hollow glass microspheres. Graphene oxide modification is performed by grafting maleic anhydride, which improves the compatibility and dispersibility with organosilicon and enhances the tensile strength and tear resistance of the foamed layer. Hollow glass microspheres are modified with silane coupling agents to improve the interfacial bonding with organosilicon. At the same time, the hollow structure further reduces the density and improves the thermal insulation and buffering performance. Modified graphene oxide and modified hollow glass microspheres are connected by chemical bonding. The two work synergistically in the modified filler to form a three-dimensional reinforcing network, which effectively prevents filler agglomeration and improves the uniformity and long-term durability of the foamed layer. Furthermore, nanofillers can act as physical cross-linking points, enhancing the mechanical properties of the interfacial region. The low density and fine pores of the foam layer, along with the closed-cell structure formed through dehydrogenation foaming, endow the material with lightweight properties, reducing overall weight. The uniform pores provide excellent cushioning and impact resistance, while also serving as thermal and sound insulation, making it suitable for high- or low-temperature environments in automotive, aerospace, and electronic equipment applications. The self-adhesive layer, based on vinyl polydimethylsiloxane, also possesses high and low temperature resistance. Working synergistically with the foam layer, it ensures stable adhesion of the entire material under temperature changes, preventing debonding due to thermal expansion and contraction. The self-adhesive layer and the foam layer have similar chemical properties, achieving interpenetrating cross-linking and forming an integrated structure.

[0027] (2) In this invention, the winding and curing process fully cross-links the self-adhesive layer, making the adhesion more stable and the interlayer bonding stronger, thus avoiding interlayer peeling or adhesion attenuation during use. The organosilicon material with -Si-O-Si- as the main chain has a higher bond energy than C-C and CO bonds, giving the material extremely high thermal stability. It is not easy to break or decompose at high temperatures, and it can still maintain excellent flexibility and elasticity at low temperatures, avoiding embrittlement and cracking. Moreover, the organosilicon material is non-toxic, odorless, green and environmentally friendly. The synergistic effect of each component makes the final product have a wide temperature range and is convenient to use.

[0028] (3) Through process optimization, the product performance of this invention is controllable and suitable for industrialization. Conventional polymer processing equipment is used, which is suitable for large-scale industrial production, is green and environmentally friendly, and has a wide range of applications. The prepared product has the characteristics of high and low temperature resistance, self-adhesion, cushioning, and decoration. It can be widely used in extreme high and low temperature environments such as automotive interiors, as well as in home decoration, industrial cushioning and other fields, with broad application prospects. Detailed Implementation

[0029] To facilitate understanding of the present invention, a more complete description will be provided below. Preferred embodiments of the invention are given below. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0030] Example 1 A modified filler, the preparation method of which includes the following steps: S1. Graphene oxide was ultrasonically dispersed in N,N-dimethylformamide. After uniform dispersion, maleic anhydride was added, wherein the mass ratio of graphene oxide, N,N-dimethylformamide and maleic anhydride was 100:18000:3000. The mixture was stirred and heated to 80°C for 3 hours. After the reaction was completed, the mixture was washed with anhydrous ethanol, freeze-dried, and ground to obtain modified graphene oxide. S2. Mix the ethanol solution and 3-aminopropyltriethoxysilane evenly, adjust the pH to 4 with acetic acid, and then add hollow glass microspheres. The mass ratio of ethanol solution, 3-aminopropyltriethoxysilane and hollow glass microspheres is 1500:32:100. Stir and mix, and react at 60°C for 6 hours. After the reaction is complete, filter, wash with deionized water and anhydrous ethanol, and dry to obtain modified hollow glass microspheres. S3. N,N-dimethylformamide, modified graphene oxide, modified hollow glass microspheres, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, 1-hydroxybenzotriazole, and triethylamine were mixed in a mass ratio of 2100:25:100:21:12:58 and stirred. The mixture was heated to 25°C and reacted for 9 hours. After the reaction was completed, the mixture was filtered, washed with anhydrous ethanol, and dried to obtain the modified filler.

[0031] Example 2 A modified filler, the preparation method of which includes the following steps: S1. Graphene oxide was ultrasonically dispersed in N,N-dimethylformamide. After uniform dispersion, maleic anhydride was added, wherein the mass ratio of graphene oxide, N,N-dimethylformamide and maleic anhydride was 100:20000:3200. The mixture was stirred and heated to 85°C for 2.5 h. After the reaction was completed, the mixture was washed with anhydrous ethanol, freeze-dried, and ground to obtain modified graphene oxide. S2. Mix the ethanol solution and 3-aminopropyltriethoxysilane evenly, adjust the pH to 4.5 with acetic acid, and then add hollow glass microspheres. The mass ratio of ethanol solution, 3-aminopropyltriethoxysilane and hollow glass microspheres is 1600:45:100. Stir and mix, and react at 65°C for 5 hours. After the reaction is complete, filter, wash with deionized water and anhydrous ethanol, and dry to obtain modified hollow glass microspheres. S3. N,N-dimethylformamide, modified graphene oxide, modified hollow glass microspheres, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, 1-hydroxybenzotriazole, and triethylamine were mixed in a mass ratio of 2200:40:100:26:14:85 and stirred. The mixture was heated to 30°C and reacted for 8 hours. After the reaction was completed, the mixture was filtered, washed with anhydrous ethanol, and dried to obtain the modified filler.

[0032] Example 3 A modified filler, the preparation method of which includes the following steps: S1. Graphene oxide was ultrasonically dispersed in N,N-dimethylformamide. After uniform dispersion, maleic anhydride was added, wherein the mass ratio of graphene oxide, N,N-dimethylformamide and maleic anhydride was 100:21000:3500. The mixture was stirred and heated to 90°C for 2 hours. After the reaction was completed, the mixture was washed with anhydrous ethanol, freeze-dried, and ground to obtain modified graphene oxide. S2. Mix the ethanol solution and 3-aminopropyltriethoxysilane evenly, adjust the pH to 5 with acetic acid, and then add hollow glass microspheres. The mass ratio of ethanol solution, 3-aminopropyltriethoxysilane and hollow glass microspheres is 1800:50:100. Stir and mix, and react at 70°C for 4 hours. After the reaction is complete, filter, wash with deionized water and anhydrous ethanol, and dry to obtain modified hollow glass microspheres. S3. N,N-dimethylformamide, modified graphene oxide, modified hollow glass microspheres, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, 1-hydroxybenzotriazole, and triethylamine were mixed in a mass ratio of 2500:48:100:30:15:95 and stirred. The mixture was heated to 35°C and reacted for 6 hours. After the reaction was completed, the mixture was filtered, washed with anhydrous ethanol, and dried to obtain the modified filler.

[0033] Example 4 A self-adhesive foamed leather resistant to high and low temperatures, the preparation method of which includes the following steps: Step 1: Mix 100 parts of hydroxyl-terminated polydimethylsiloxane and 5 parts of modified filler evenly. Add 1 part of hydrogen-containing silicone oil, 0.01 parts of platinum catalyst, and 0.001 parts of inhibitor tetramethyltetravinylcyclotetrasiloxane. Stir at high speed (1000 rpm) for 120 seconds to form a foamed layer. Roll-coat the foamed layer onto a roughened base fabric layer with a thickness of 0.1 mm. Cure the foamed layer at 80°C to form a foamed layer with a density of 0.3 g / cm³. 3 The foam pore diameter is 50μm, and a composite preform of base fabric layer-foamed layer is obtained; Step 2: Mix 100 parts of vinyl polydimethylsiloxane and 20 parts of MQ silicone resin evenly, add 3 parts of hydrogen-containing silicone oil, 0.01 parts of platinum catalyst and 0.001 parts of inhibitor tetramethyltetravinylcyclotetrasiloxane, mix to obtain a self-adhesive paste, roll the self-adhesive paste onto the surface of the foam layer, and cure at 80°C to form a self-adhesive layer with a thickness of 10μm, thus obtaining a composite preform of base fabric layer-foam layer-self-adhesive layer; Step 3: Apply a fluorosilicone resin release film to the surface of the self-adhesive layer, and press it together to form a release layer with a thickness of 20μm. Then, roll it up and cure it at a temperature of 25℃ for 96 hours to obtain a self-adhesive foamed leather that is resistant to high and low temperatures.

[0034] The preparation method of the modified filler in this embodiment is completely consistent with the preparation method of the modified filler in Example 1.

[0035] Example 5 A self-adhesive foamed leather resistant to high and low temperatures, the preparation method of which includes the following steps: Step 1: Mix 100 parts of hydroxyl-terminated polydimethylsiloxane and 6 parts of modified filler evenly. Add 5 parts of hydrogen-containing silicone oil, 0.2 parts of platinum catalyst, and 0.04 parts of inhibitor tetramethyltetravinylcyclotetrasiloxane. Stir at high speed (2000 rpm) for 90 seconds to form a foamed layer. Roll-coat the foamed layer onto a roughened base fabric layer with a thickness of 0.6 mm. Cure the foamed layer at 100°C to form a foamed layer with a density of 0.4 g / cm³. 3 The foam diameter is 135μm, and a composite preform of base fabric layer-foamed layer is obtained; Step 2: Mix 100 parts of vinyl polydimethylsiloxane and 32 parts of MQ silicone resin evenly, add 8 parts of hydrogen-containing silicone oil, 0.05 parts of platinum catalyst and 0.02 parts of inhibitor tetramethyltetravinylcyclotetrasiloxane, and mix to obtain a self-adhesive paste. Roll the self-adhesive paste onto the surface of the foam layer and cure it at 95°C to form a self-adhesive layer with a thickness of 45μm, thus obtaining a composite preform of base fabric layer-foam layer-self-adhesive layer. Step 3: Apply a fluorosilicone release film to the surface of the self-adhesive layer, and press it together to form a release layer with a thickness of 60μm. Then, roll it up and cure it at a temperature of 30℃ for 84 hours to obtain a self-adhesive foamed leather that is resistant to high and low temperatures.

[0036] The preparation method of the modified filler in this embodiment is completely consistent with the preparation method of the modified filler in Example 2.

[0037] Example 6 A self-adhesive foamed leather resistant to high and low temperatures, the preparation method of which includes the following steps: Step 1: Mix 100 parts of hydroxyl-terminated polydimethylsiloxane and 7 parts of modified filler evenly. Add 7 parts of hydrogen-containing silicone oil, 0.4 parts of platinum catalyst, and 0.07 parts of inhibitor tetramethyltetravinylcyclotetrasiloxane. Stir at high speed (2000 rpm) for 105 seconds to form a foamed layer. Roll-coat the foamed layer onto a roughened base fabric layer with a thickness of 0.6 mm. Cure the foamed layer at 105°C to form a foamed layer with a density of 0.5 g / cm³. 3 The foam diameter is 160μm, and a composite preform of base fabric layer-foamed layer is obtained; Step 2: Mix 100 parts of vinyl polydimethylsiloxane and 45 parts of MQ silicone resin evenly, add 12 parts of hydrogen-containing silicone oil, 0.08 parts of platinum catalyst and 0.04 parts of inhibitor tetramethyltetravinylcyclotetrasiloxane, mix to obtain a self-adhesive paste, roll the self-adhesive paste onto the surface of the foam layer, and cure at 105℃ to form a self-adhesive layer with a thickness of 45μm, thus obtaining a composite preform of base fabric layer-foam layer-self-adhesive layer; Step 3: Apply a fluorosilicone release film to the surface of the self-adhesive layer, and press it together to form a release layer with a thickness of 60μm. Then, roll it up and cure it at a temperature of 30℃ for 84 hours to obtain a self-adhesive foamed leather that is resistant to high and low temperatures.

[0038] The preparation method of the modified filler in this embodiment is completely consistent with the preparation method of the modified filler in Example 2.

[0039] Example 7 A self-adhesive foamed leather resistant to high and low temperatures, the preparation method of which includes the following steps: Step 1: Mix 100 parts of hydroxyl-terminated polydimethylsiloxane and 8 parts of modified filler evenly. Add 10 parts of hydrogen-containing silicone oil, 0.5 parts of platinum catalyst, and 0.1 parts of inhibitor tetramethyltetravinylcyclotetrasiloxane. Stir at high speed (3000 rpm) for 60 seconds to form a foamed layer. Roll-coat the foamed layer onto a roughened base fabric layer with a thickness of 1.0 mm. Cure the foamed layer at 120°C to form a foamed layer with a density of 0.6 g / cm³. 3The foam pore diameter is 200μm, and a composite preform of base fabric layer-foamed layer is obtained; Step 2: Mix 100 parts of vinyl polydimethylsiloxane and 60 parts of MQ silicone resin evenly, add 15 parts of hydrogen-containing silicone oil, 0.1 parts of platinum catalyst and 0.05 parts of inhibitor tetramethyltetravinylcyclotetrasiloxane, mix to obtain a self-adhesive paste, roll the self-adhesive paste onto the surface of the foam layer, and cure at 120°C to form a self-adhesive layer with a thickness of 50μm, thus obtaining a composite preform of base fabric layer-foam layer-self-adhesive layer; Step 3: Apply a fluorosilicone release film to the surface of the self-adhesive layer, and press it together to form a release layer with a thickness of 100μm. Then, roll it up and cure it at a temperature of 35℃ for 72 hours to obtain a self-adhesive foamed leather that is resistant to high and low temperatures.

[0040] The preparation method of the modified filler in this embodiment is completely consistent with the preparation method of the modified filler in Example 3.

[0041] Comparative Example 1 A method for preparing self-adhesive foamed leather, compared with the method for preparing self-adhesive foamed leather in Example 6, differs in the preparation method of the base fabric layer-foamed layer composite blank, while the other preparation methods are completely consistent with Example 6.

[0042] The preparation method of the base fabric-foamed layer composite preform in this comparative example includes the following steps: 100 parts polyurethane resin, 5 parts azodicarbonamide (a foaming agent), and 3 parts trimethylolpropane (a crosslinking agent) were mixed evenly and then roller-coated onto a roughened base fabric layer. The base fabric layer had a thickness of 1.0 mm. The mixture was then foamed and cured at 150°C to form a foamed layer with a density of 0.6 g / cm³. 3 A composite preform of base fabric layer-foam layer with a thickness of 0.8 mm was obtained.

[0043] Comparative Example 2 A method for preparing self-adhesive foamed leather is provided. Compared with the method for preparing self-adhesive foamed leather in Example 6, the difference lies in the preparation method of the self-adhesive layer. The other preparation methods are completely consistent with those in Example 6.

[0044] The self-adhesive layer preparation method in this comparative example includes the following steps: Mix 100 parts of acrylic pressure-sensitive adhesive and 2 parts of curing agent isocyanate evenly, apply the mixture to the surface of the foam layer, and cure at 100°C to form a self-adhesive layer with a thickness of 45 μm.

[0045] Comparative Example 3 A method for preparing self-adhesive foamed leather, compared with the method for preparing self-adhesive foamed leather in Example 6, differs in that the modified filler used in the foaming layer is different. The modified filler used in this comparative example consists of graphene oxide and hollow glass microspheres in a mass ratio of 2:5, which is an equal substitution of the modified filler used in Example 6. The other preparation methods are completely consistent with those in Example 6.

[0046] The high and low temperature resistant self-adhesive foamed leathers prepared in Examples 4-7 and Comparative Examples 1-3 were subjected to relevant performance tests, as follows: (1) Low temperature resistance test: The test standard refers to GB / T 38465-2020. The sample is placed in an environment of -40℃. After 24 hours, the test is carried out according to the above standard method A. After the sample returns to room temperature, the sample is removed and its surface condition is observed visually. (2) High temperature resistance test: The test standard refers to GB / T 3512-2014. The sample is placed in a constant temperature chamber at 150℃ for 1000h. The sample surface is observed to see if there is shrinkage, cracking, discoloration or delamination. (3) Peel strength test: The test standard refers to QB / T 2713-2018. The 180° peel method is used. A sample of the specified size is cut from the finished product or the simulation part, such as 25mm wide and 200mm long. A tensile testing machine is used to peel at a constant speed of 300mm / min. The peel strength is the average value of the stable segment of the force-displacement curve. The average value is taken three times. The test results are shown in Table 1: Table 1

[0047] As can be seen from the test results in Table 1, the samples in Examples 4-7 of this invention exhibit excellent high and low temperature resistance. No cracks or damage were observed after 24 hours at -40℃, indicating good compatibility between the modified filler and the organosilicon matrix, and excellent low-temperature toughness. No shrinkage, cracking, discoloration, or delamination were observed after 150℃×1000h, mainly due to the good synergistic heat resistance stability between the raw materials. In Comparative Example 1, the polyurethane foam layer showed significant low-temperature brittleness, cracking, and insufficient heat resistance, resulting in shrinkage and delamination. In Comparative Example 2, the acrylic pressure-sensitive adhesive exhibited poor heat resistance, discoloration, and decreased adhesion, with low peel strength. In Comparative Example 3, due to the lack of chemically bonded modified fillers, the interfacial bonding between graphene oxide and hollow glass microspheres was weak at high temperatures, leading to localized cracking. Furthermore, the unmodified filler showed poor dispersion and interfacial interaction in the system, resulting in reduced peel strength.

[0048] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. A self-adhesive foamed leather resistant to high and low temperatures, characterized in that: From top to bottom, it includes a base fabric layer, a foam layer, a self-adhesive layer, and a release layer; The foamed layer is formed by dehydrogenation foaming of organosilicon and has a density of 0.3~0.6 g / cm³. 3 The pore diameter is 50~200μm; The self-adhesive layer is an organic silicone adhesive with a thickness of 10~50μm; The release layer is a fluororesin release film with a thickness of 20~100μm.

2. The high and low temperature resistant self-adhesive foamed leather according to claim 1, characterized in that: The surface of the base fabric layer is brushed, and the thickness of the base fabric layer is 0.1~1.0mm, including any one of knitted fabric, woven fabric, non-woven fabric, artificial leather, and animal leather.

3. The high and low temperature resistant self-adhesive foamed leather according to claim 1, characterized in that: The foamed layer comprises the following raw materials in parts by weight: 100 parts of hydroxyl-terminated polydimethylsiloxane, 1-10 parts of hydrogen-containing silicone oil, 0.01-0.5 parts of platinum catalyst, 0.001-0.1 parts of inhibitor, and 5-8 parts of modified filler.

4. The high and low temperature resistant self-adhesive foamed leather according to claim 3, characterized in that: The method for preparing the modified filler in the foamed layer includes the following steps: S1. Graphene oxide was ultrasonically dispersed in N,N-dimethylformamide. After uniform dispersion, maleic anhydride was added, stirred and mixed, heated, and reacted. After the reaction was completed, the mixture was washed with anhydrous ethanol, freeze-dried, and ground to obtain modified graphene oxide. S2. Mix the ethanol solution and 3-aminopropyltriethoxysilane evenly, adjust the pH to 4-5 with acetic acid, add hollow glass microspheres, stir and mix to allow the reaction to occur. After the reaction is complete, filter, wash with deionized water and anhydrous ethanol, and dry to obtain modified hollow glass microspheres. S3. N,N-dimethylformamide, modified graphene oxide, modified hollow glass microspheres, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, 1-hydroxybenzotriazole, and triethylamine are stirred and mixed, heated, and reacted. After the reaction is completed, the mixture is filtered, washed with anhydrous ethanol, and dried to obtain the modified filler.

5. The high and low temperature resistant self-adhesive foamed leather according to claim 4, characterized in that: The mass ratio of N,N-dimethylformamide, modified graphene oxide, modified hollow glass microspheres, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, 1-hydroxybenzotriazole, and triethylamine in S3 is (2100~2500):(25~48):100:(21~30):(12~15):(58~95), the reaction temperature is 25~35℃, and the reaction time is 6~9h.

6. The high and low temperature resistant self-adhesive foamed leather according to claim 1, characterized in that: The self-adhesive layer comprises the following raw materials in parts by weight: 100 parts of vinyl polydimethylsiloxane, 3-15 parts of hydrogen-containing silicone oil, 20-60 parts of MQ silicone resin, 0.01-0.1 parts of platinum catalyst, and 0.001-0.05 parts of inhibitor.

7. The high and low temperature resistant self-adhesive foamed leather according to claim 1, characterized in that: The fluororesin is selected from at least one of polytetrafluoroethylene, polyvinylidene fluoride, and fluorosilicone resin.

8. A method for preparing high and low temperature resistant self-adhesive foamed leather as described in any one of claims 1-7, characterized in that: Includes the following steps: Step 1: After the base fabric layer is roughened, hydroxyl-terminated polydimethylsiloxane and modified filler are mixed evenly, hydrogen-containing silicone oil, platinum catalyst and inhibitor are added, and coated on the base fabric layer. The mixture is then foamed and cured at 80~120℃ to form a foamed layer, thus obtaining a base fabric layer-foamed layer composite preform. Step 2: Mix vinyl polydimethylsiloxane and MQ silicone resin evenly, add hydrogen-containing silicone oil, platinum catalyst and inhibitor, mix to obtain self-adhesive paste, coat the self-adhesive paste on the surface of the foam layer, and cure at 80~120℃ to form a self-adhesive layer, thus obtaining a composite preform of base fabric layer-foam layer-self-adhesive layer. Step 3: Apply fluoropolymer release film to the surface of the self-adhesive layer, press and bond it with the self-adhesive layer to form a release layer, and then roll it up and cure it. The curing temperature is 25~35℃ and the curing time is 72~96h to obtain self-adhesive foamed leather that is resistant to high and low temperatures.

9. The method for preparing a high and low temperature resistant self-adhesive foamed leather according to claim 8, characterized in that: In step one, the stirring speed for foaming is 1000~3000 rpm, and the time is 60~120s.

10. The method for preparing a high and low temperature resistant self-adhesive foamed leather according to claim 8, characterized in that: In step two, during the preparation of the self-adhesive layer, the coating method for the self-adhesive layer is either scraping or roller coating.

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