Rubbing-resistant organosilicon-based vehicle fabric and preparation method thereof

Abstract

The invention discloses a rubbing-resistant organosilicon-based vehicle fabric and a preparation method thereof, and relates to the technical field of layered products. The gradient composite coating comprises a polyester base material layer and a gradient composite coating, the gradient composite coating is formed by sequentially superposing an adhesion bottom layer, an elastic middle layer and a wear-resistant surface layer, each layer takes modified organic silicon resin as a substrate material, and the modified organic silicon resin is prepared by firstly carrying out chain extension reaction on hydroxyl-terminated organic silicon resin and an amino silane coupling agent to introduce an anchoring group and then carrying out chain extension reaction on the hydroxyl-terminated organic silicon resin and the amino silane coupling agent. Then carrying out a cross-linking reaction with an isocyanate cross-linking agent to form a three-dimensional network molecular structure, so as to strengthen interlayer bonding and structural stability; through cooperative application of core technologies such as anchoring, cross-linking modification, gradient coating function integration and three-wavelength ultraviolet gradient curing, multi-performance cooperative optimization of rubbing resistance, interlayer binding strength, extreme environment adaptability and VOCs release amount of the vehicle fabric is achieved.

Description

Technical Field

[0001] This invention relates to the field of layered product technology, particularly to the field of automotive functional fabric technology, specifically to a rub-resistant silicone-based automotive fabric and its preparation method. Background Technology

[0002] Currently, most mainstream automotive fabrics are prepared using polyurethane coating or ordinary silicone coating processes. These fabrics have inherent technical shortcomings: the coating and the substrate only have physical adsorption, and the molecular bonding force is weak. In the high-frequency contact and repeated rubbing scenarios of automotive interiors, failure phenomena such as coating peeling, flaking, surface fuzzing and pilling are prone to occur, and the service life is generally less than 3 years. In low-temperature environments below -20℃, the coating is prone to brittleness and the substrate is prone to hardening. In high-temperature environments above 70℃, it is prone to releasing VOCs and irritating odors, which cannot meet the high requirements of new energy vehicles for interior quality and environmental protection standards.

[0003] Existing technologies for improving the abrasion resistance of fabrics have significant limitations: some technologies improve abrasion resistance by increasing coating thickness, but this results in a stiff fabric feel, reduced flexibility, and exacerbated stress concentration between layers, which in turn reduces coating adhesion. Other technologies improve coating elasticity by optimizing a single silicone formulation, but it is difficult to balance abrasion resistance and substrate adhesion, failing to achieve synergistic optimization of multiple properties. From an industry perspective, the domestic high-end automotive functional fabric market has long been monopolized by foreign companies. Core modified resin formulations and gradient coating processes are dependent on foreign suppliers. Imported products are not only expensive (3-5 times more expensive than domestic ordinary fabrics), but also have long delivery cycles and slow customization responses, severely restricting the independent and high-end development of the domestic automotive interior industry chain.

[0004] As the global automotive industry transforms towards high-end, intelligent, and green technologies, automotive interior fabrics, as core components affecting driving experience and interior durability, are facing continuously upgrading performance requirements. Weather resistance, mechanical abrasion resistance, low VOC emissions, and stability in extreme environments have become the direction that the industry is constantly pursuing for progress. Therefore, there is an urgent need to develop an organosilicon-based automotive fabric that combines high abrasion resistance, strong interlayer bonding strength, excellent adaptability to extreme environments, and low VOC emissions. At the same time, it is necessary to construct a manufacturing process that can be industrialized and scaled up, thereby breaking through existing technological bottlenecks and import dependence, and promoting the upgrading of the automotive fabric industry towards high-end technologies. Summary of the Invention

[0005] The purpose of this invention is to provide a rub-resistant silicone-based automotive fabric and its preparation method, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a rub-resistant silicone-based automotive fabric, wherein the fabric comprises, from bottom to top, a polyester substrate layer, an adhesive underlayer, an elastic intermediate layer, and an abrasion-resistant surface layer, with the following thickness percentages for each layer: polyester substrate layer 85-90%, adhesive underlayer 2-3%, elastic intermediate layer 4-6%, and abrasion-resistant surface layer 3-5%;

[0007] The polyester substrate layer is made of woven polyester fiber fabric, and the side that contacts the substrate is pretreated in preparation for bonding with the substrate. The substrate, by weight, includes 80-100 parts modified silicone resin, 8-10 parts titanium dioxide filler, and 1-1.5 parts photocrosslinking agent, with a dry film thickness of 8-10 μm. The elastic intermediate layer, by mass parts, includes 30-50 parts of modified silicone resin, 50-70 parts of polydimethylsiloxane elastomer, and 1 part of ultraviolet absorber, wherein the total amount of modified silicone resin and polydimethylsiloxane elastomer is 100 parts, and the dry film thickness of the coating is 15-20 μm. The wear-resistant surface layer, by weight, includes 90-95 parts of modified silicone resin and 5-10 parts of nano-silicon carbide particles, with a dry film thickness of 12-15 μm. The modified organosilicon resins are all hydroxyl-terminated organosilicon resins. They first undergo a chain extension reaction with an aminosilane coupling agent to introduce amino anchoring groups, and then undergo a cross-linking reaction with an isocyanate cross-linking agent to form a three-dimensional network molecular structure.

[0008] Preferably, the basis weight of the polyester fiber woven fabric is 260–300 g / m². 2 The pretreatment includes degreasing, mechanical roughening, and plasma activation. The surface roughness is controlled at 1.2–1.6 μm, and the water contact angle is ≤30°.

[0009] Preferably, the hydroxyl-terminated silicone resin is a hydroxyl-terminated polydimethylsiloxane resin with a molecular weight of 120,000 to 150,000, and the aminosilane coupling agent is KH-560, with a mass ratio of (95-98):(2-5); the amount of isocyanate crosslinking agent added is 1.5-2.5% of the total mass of the modified silicone resin, and 0.3-0.8% of the total mass of the modified silicone resin is added during the crosslinking reaction.

[0010] Preferably, the photocrosslinking agent is 1-hydroxycyclohexylphenyl ketone, the titanium dioxide filler has a particle size of 1-3 μm, the solid content of the underlying slurry is controlled at 55%±2%, the polydimethylsiloxane elastomer has a Shore hardness of 50-60A, the ultraviolet absorber is UV-327, and the nano-silicon carbide particles have a particle size of 50-100 nm.

[0011] Preferably, the overall thickness of the above-mentioned fabric is 1.2 to 1.5 mm, and after 50,000 Martindale rubbing tests, the coating is intact, without peeling or pilling, the pilling level is not lower than level 4, and the breaking strength retention rate is ≥85%.

[0012] Another technical solution provided by the present invention: The preparation method of the above-mentioned rub-resistant silicone-based automotive fabric includes the following steps: 1) The polyester substrate layer is subjected to degreasing, mechanical roughening, and plasma activation pretreatment in sequence; 2) Synthesis of modified organosilicon resin: Hydroxyl-terminated organosilicon resin and aminosilane coupling agent were reacted under nitrogen protection, at 75±2℃ and 300~500r / min with constant stirring until the chain extension reaction was completed; after adding isocyanate crosslinking agent, the temperature was raised to 85±2℃ and the reaction was continued at a constant temperature until 1720cm -1 The reaction was stopped when the characteristic absorption peak of urethane ester appeared nearby. A dispersant was added to adjust the rotational viscosity of the slurry to 2800–3200 cP. 3) Gradient coating slurry preparation: Prepare the adhesion base layer, elastic intermediate layer, and wear-resistant surface layer slurries according to the specified proportions, and disperse them evenly. 4) Coating each layer sequentially onto the polyester substrate layer. The underlayer is coated with high-pressure airless spraying. After coating, it is pre-baked to remove volatile components from the slurry while retaining the coating's tackiness. The elastic intermediate layer is coated with rollers. After coating, it is pre-baked to achieve initial interlayer bonding. The abrasion-resistant surface layer is coated with a precision doctor blade. After coating, the coating temperature is kept at a suitable temperature to prevent slurry from dripping or clumping. 5) The coated fabric undergoes a three-stage UV curing process under nitrogen protection. The first stage uses UV light with a wavelength of 320nm and an irradiation intensity of 800±50mJ / cm². 2 The curing time is 1.5–2.5 min, the second stage of ultraviolet light wavelength is 365 nm, and the irradiation intensity is 1000 ± 50 mJ / cm². 2 The curing time is 2.5–3.5 min, the wavelength of the third ultraviolet light is 395 nm, and the irradiation intensity is 600 ± 50 mJ / cm². 2 The curing time is 0.5–1.5 min, and the gel rate of the cured coating is ≥95%. 6) After curing, the product is obtained by hot pressing and surface treatment.

[0013] Preferably, the pretreatment includes first immersing the polyester substrate layer in a neutral degreasing agent solution at 50±2℃ for 20 minutes, with a bath ratio of 1:20, and using ultrasonic power of 200W to assist in degreasing, removing oil, wax, and impurities from the substrate surface; then performing double-sided mechanical roughening treatment with 120-grit white corundum sandpaper, controlling the sanding rate at 1.5m / min; finally placing it in a plasma treatment device and treating it for 30 seconds under an argon atmosphere with a power of 300W; and finally placing the pretreated substrate in a standard environment for 30 minutes to eliminate surface stress.

[0014] Preferably, the slurry adhering to the bottom layer is dispersed in a high-speed disperser at 2000 r / min for 20 min, and then ground by a three-roll mill with a gap of 5-10 μm; the slurry of the elastic intermediate layer is dispersed in an ultrasonic disperser for 15 min at a power of 500 W, and then stirred at a constant temperature of 60°C and 300 r / min for 10 min; the slurry of the wear-resistant surface layer is first dispersed in a high-speed disperser at 3000 r / min for 30 min, and then dispersed in an ultrasonic disperser for 20 min at a power of 800 W, controlling the agglomeration particle size of the nanoparticles to be ≤200 nm.

[0015] Preferably, the spraying pressure for the substrate is 0.5MPa±0.05MPa, the distance between the spray gun and the substrate is 250mm±10mm, the spraying rate is 1.2m / min, and the coating is pre-baked at 60±2℃ for 3min; the elastic intermediate layer is coated by a double roller with a roller speed ratio of 1:1.5, a coating pressure of 0.1MPa, and the coating is pre-baked at 70±2℃ for 2min; the coating blade gap for the wear-resistant surface layer is 20μm±2μm, the coating speed is 1.5m / min, and the coating temperature is maintained at 40±5℃ after coating.

[0016] Preferably, the hot pressing in step 6) is performed at a temperature of 120±2℃ and a pressure of 0.2±0.02MPa for 5 minutes; the surface treatment is performed by spraying with a fluorinated silane finishing agent and then drying.

[0017] Compared with the prior art, the beneficial effects of the present invention are: 1. This rub-resistant silicone-based automotive fabric and its preparation method integrate the molecular design of "anchoring-crosslinking" modified silicone resin with gradient coating function. The wear-resistant surface layer forms a wear-resistant skeleton with nano-silicon carbide particles, the elastic middle layer buffers the rubbing stress, and the adhesion bottom layer strengthens the bonding strength, thus synergistically improving the fabric's rub resistance performance, resulting in a significant leap in the fabric's rub resistance performance. After 50,000 Martindale rub tests, the coating remains intact, without peeling or pilling, the breaking strength retention rate is ≥85%, the pilling level reaches level 4 or above, and the service life can be extended to more than 8 years, which can perfectly meet the usage needs of high-frequency contact scenarios in automotive interiors.

[0018] 2. This rub-resistant silicone-based automotive fabric and its preparation method exhibit excellent interlayer bonding strength. The amino anchoring groups of the modified silicone resin form chemical bonds with the active sites on the surface of the pretreated substrate. Combined with a three-dimensional network cross-linking structure and a three-step substrate activation process, the peel strength between the coating and the substrate is ≥5.5N / 25mm. After aging treatment by storing at -30℃ for 24 hours and at 80℃ for 24 hours, the peel strength retention rate is still ≥80%, completely solving the technical problems of easy peeling and curling of traditional fabric coatings.

[0019] 3. This rub-resistant silicone-based automotive fabric combines extreme environmental adaptability with environmental friendliness: the elastic intermediate layer of PDMS elastomer gives the fabric excellent temperature deformation resistance, while the UV absorber enhances its resistance to light aging, ensuring stable performance of the fabric in environments ranging from -30 to 80℃, without brittleness or odor; the solvent-free formula design, combined with precise process control, results in a finished product with formaldehyde release ≤0.02mg / m³ and total VOCs release ≤0.5mg / m³, meeting the EU E1 environmental standard and low VOCs requirements for automotive interiors.

[0020] 4. The rub-resistant silicone-based automotive fabric and its preparation method adopt a three-wavelength ultraviolet gradient curing method, which shortens the traditional ultraviolet curing time from 20 minutes to about 6 minutes and reduces energy consumption by more than 30%. It can realize continuous industrial production, and the product performance is stable and controllable, which is conducive to reducing automobile production costs.

[0021] 5. This rub-resistant silicone-based automotive fabric and its preparation method, through the synergistic application of core technologies such as "anchoring-crosslinking" modification, gradient coating functional integration, and three-wavelength ultraviolet gradient curing, achieves multi-performance optimization of automotive fabrics in terms of rub resistance, interlayer bonding strength, extreme environmental adaptability, and VOCs emission. Compared with existing technologies, it has significant technical advantages and industrial value, and is especially suitable for application in the field of high-end new energy vehicle interiors, promoting the quality improvement of automotive functional fabrics. Detailed Implementation

[0022] To overcome the technical deficiencies of existing automotive fabrics mentioned in the background section, this invention achieves a synergistic improvement in multiple properties of the fabric, including abrasion resistance, elasticity, adhesion, and environmental friendliness, through the molecular design of "anchoring-crosslinking" modified silicone resin, functional integration of gradient coating, and synergistic optimization of multiple processes. Specifically, the abrasion-resistant silicone-based automotive fabric of this invention includes a substrate layer and a gradient coating. From bottom to top (here, "top" and "bottom" are for ease of description and do not refer to actual spatial relationships), the layers are a polyester substrate layer, an adhesion underlayer, an elastic intermediate layer, and an abrasion-resistant surface layer. The thickness percentages of each layer are: polyester substrate layer 85-90%, adhesion underlayer 2-3%, elastic intermediate layer 4-6%, and abrasion-resistant surface layer 3-5%. The overall fabric thickness can be controlled within 1.2-1.5 mm, balancing structural stability and flexibility. The specific composition of each layer and the slurry preparation process are as follows: The polyester substrate layer is selected with a basis weight of 260-300 g / m². 2The high-density polyester fiber woven fabric has a side that is in contact with the substrate that is pretreated as preparation for bonding with the substrate. More preferably, the pretreatment can be carried out in three steps of fine operation: degreasing, mechanical roughening and plasma activation. The purpose is to control the surface roughness of the substrate after pretreatment to 1.2 to 1.6 μm and the water contact angle ≤30°, so as to ensure that the substrate surface has excellent coating wettability and bonding sites. For reference, the pretreatment can be carried out as follows: First, immerse the polyester substrate layer in a degreasing agent solution at 50±2℃ for 20 minutes. The degreasing agent can be a neutral degreasing agent such as fatty alcohol polyoxyethylene ether, with a bath ratio of 1:20. Use ultrasonic-assisted degreasing, and the ultrasonic power can be set to 200W to remove oil, wax and impurities from the substrate surface. Then, use 120-grit white corundum sandpaper for double-sided mechanical roughening treatment, controlling the sanding rate at 1.5m / min. Finally, place it in a plasma treatment device and treat it under an argon atmosphere for 30 seconds. The argon flow rate can be controlled at 10~15L / min, and the power can be controlled at 300W. After pretreatment, place the substrate in a standard environment (temperature 23±2℃, relative humidity 50±5%RH) and let it stand for 30 minutes to eliminate surface stress.

[0023] The substrate, by weight, comprises 80-100 parts modified silicone resin, 8-10 parts titanium dioxide filler, and 1-1.5 parts photocrosslinking agent, with a dry film thickness of 8-10 μm. Optionally, the photocrosslinking agent is 1-hydroxycyclohexylphenyl ketone to ensure efficient UV curing, and the titanium dioxide filler has a particle size of 1-3 μm to improve the coating's hiding power and adhesion to the substrate. For reference, the solid content of the substrate slurry should be controlled at 55% ± 2%. The slurry is dispersed in a high-speed disperser at 2000 r / min for 20 min, and then ground by a three-roll mill with a gap of 5-10 μm. The elastic interlayer, by weight, comprises 30-50 parts of modified silicone resin, 50-70 parts of polydimethylsiloxane (PDMS) elastomer, and 1 part of UV absorber, wherein the total amount of modified silicone resin and PDMS elastomer is 100 parts, and the dry film thickness of the coating is 15-20 μm. More preferably, the PDMS elastomer has a Shore hardness of 50-60A, which imparts excellent flexibility and deformation resistance to the fabric. The UV absorber is UV-327, which enhances the fabric's resistance to light aging. For reference, the slurry of the elastic interlayer is dispersed in an ultrasonic disperser for 15 minutes at a power of 500W, followed by constant temperature stirring at 60°C and 300 rpm for 10 minutes. The wear-resistant surface layer, by mass parts, includes 90-95 parts of modified silicone resin and 5-10 parts of nano-silicon carbide particles, with a dry film thickness of 12-15 μm. The preferred particle size of the nano-silicon carbide particles is 50-100 nm. For preparation, the slurry can be dispersed for 30 min at 3000 r / min using a high-speed disperser, followed by 20 min using an ultrasonic disperser with a power of 800 W, to control the agglomeration particle size of the nanoparticles to ≤200 nm. The modified silicone resins used in each of the above layers are all hydroxyl-terminated silicone resins that undergo a chain extension reaction with an amino silane coupling agent to introduce amino anchoring groups, and then undergo a cross-linking reaction with an isocyanate cross-linking agent to form a three-dimensional network molecular structure. Specifically, the following steps can be referenced: Hydroxyl-terminated polydimethylsiloxane resin with a molecular weight of 120,000 to 150,000 is used as raw material, and mixed with an amino silane coupling agent (preferably KH-560) at a mass ratio of (95-98):(2-5). The mixture is placed in a reaction vessel and stirred at a constant temperature of 75±2℃ and a rotation speed of 300-500 r / min until the chain extension reaction is complete. Amino anchoring groups are introduced onto the lipid molecular chain; subsequently, 1.5–2.5% of an isocyanate crosslinking agent (preferably hexamethylene diisocyanate trimer) is added by mass of the total resin, and the temperature is raised to 85±2℃ for a continued isothermal reaction to form a three-dimensional network crosslinked structure; during the reaction, 0.3–0.8% of a composite dispersant (ammonium polyacrylate and glycerol in a 1:1 mass ratio) is added by mass of the total resin to control the rotational viscosity of the slurry between 2800 and 3200 cP, ensuring uniform dispersion and coating stability of the resin system. The specific timing of addition can be detected by Fourier transform infrared spectroscopy (FT-IR), when the viscosity is 1720 cm⁻¹. -1 The reaction is stopped when the characteristic absorption peak of urethane ester appears nearby. After each layer of slurry is prepared, the coatings are sequentially applied to the treated polyester substrate layer. The following coating methods are preferred for each layer: The substrate is coated with high-pressure airless spraying, and then pre-baked to remove volatile components from the slurry while retaining the coating's tackiness. The elastic intermediate layer is coated by roller coating, and pre-baking after coating achieves initial bonding between layers; The wear-resistant surface layer is coated with a precision scraper, and the coating temperature is kept at a suitable temperature after coating to prevent the slurry from dripping or clumping. In a preferred embodiment, the spraying pressure for the substrate is 0.5 MPa ± 0.05 MPa, the distance between the spray gun and the substrate is 250 mm ± 10 mm, the spraying rate is 1.2 m / min, and the coating is pre-baked at 60 ± 2℃ for 3 min after coating to remove volatile components from the slurry and retain the coating's tackiness; the elastic intermediate layer is coated by a double roller with a roller speed ratio of 1:1.5 and a coating pressure of 0.1 MPa, and is pre-baked at 70 ± 2℃ for 2 min after coating to achieve initial interlayer bonding; the coating blade gap for the wear-resistant surface layer is 20 μm ± 2 μm, the coating speed is 1.5 m / min, and the coating temperature is monitored in real time by an infrared thermometer and maintained at 40 ± 5℃ to prevent slurry sagging or clumping.

[0024] In addition to the above processes, this invention also significantly improves production efficiency. Traditional UV curing takes 20 minutes, while the fabric coated by this invention undergoes a three-stage UV curing process under nitrogen protection (to prevent the coating from oxidizing and yellowing). The first stage uses UV light with a wavelength of 320nm and an irradiation intensity of 800±50mJ / cm. 2 The curing time is 1.5–2.5 minutes, achieving initial curing of the adhesion layer and enhancing the bonding strength with the substrate. The second stage uses ultraviolet light with a wavelength of 365 nm and an irradiation intensity of 1000±50 mJ / cm². 2 The curing time is 2.5–3.5 min, achieving deep curing of the elastic intermediate layer and the wear-resistant surface layer, forming a stable cross-linked structure. The third segment of ultraviolet light has a wavelength of 395 nm and an irradiation intensity of 600 ± 50 mJ / cm. 2 The curing time is 0.5–1.5 min, which eliminates internal stress in the coating, improves structural stability, and results in a coating gel rate of ≥95% after curing. After curing, the fabric is sent to a hot-pressing and setting equipment, where it is hot-pressed and set for 5 minutes at a temperature of 120±2℃ and a pressure of 0.2±0.02MPa to improve the density of the coating and the smoothness of the fabric. Subsequently, a 1% concentration of fluorinated silane finishing agent (preferably perfluorooctyltriethoxysilane) can be applied by spraying, with a preferred spraying amount of 10-15g / ㎡. The fabric is then dried at 80±2℃ for 5 minutes to make the water contact angle of the fabric surface ≥110°, giving it hydrophobic and stain-resistant properties. Finally, the fabric is cut to the size according to automotive interior specifications, and its appearance is inspected through a 5x magnifying glass. The absence of defects such as pinholes, scratches, and coating runs indicates that the product is qualified. Randomly selected samples are subjected to a rubbing test (Martindale tester, pressure 12kPa). The absence of coating peeling and pilling indicates that the product is a finished product.

[0025] The technical solution of the present invention will be further described in detail below with reference to specific embodiments, but its protection scope is not limited thereto. Experimental methods in the embodiments that do not specify specific conditions are all performed according to conventional methods and conditions commonly used in the prior art; all raw materials used are commercially available conventional raw materials that can be directly purchased and obtained, wherein: Hydroxyl-terminated polydimethylsiloxane resin: Yunnan Energy Investment Green New Materials Co., Ltd. Aminosilane coupling agents: Nanjing Shuguang Chemical Group Co., Ltd. Nano-silicon carbide particles: Zhejiang Zhoushan Hongbo New Materials Co., Ltd. Polydimethylsiloxane elastomer: Shenzhen Ruihuatai Thin Film Technology Co., Ltd. 1-Hydroxycyclohexylphenyl ketone: Shanghai Tongyuan Chemical Co., Ltd. Fatty alcohol polyoxyethylene ether (neutral degreasing agent): Guangzhou Langqi Industrial Co., Ltd. Perfluorooctyltriethoxysilane: Experimental factory of the Institute of Organosilicon Materials, Hangzhou Normal University All embodiments and comparative examples were prepared according to the above-described scheme, and the technical effects of the present invention were verified through performance testing.

[0026] The detection methods in the following examples and comparative cases include: Martindale rubbing test: GB / T 21196.2-2007 "Textiles - Martindale Method for Determination of Abrasion Resistance of Fabrics - Part 2: Determination of Specimen Breakage"; Tensile strength retention rate: GB / T 3923.1-2013 "Textiles - Tensile properties of fabrics - Part 1: Determination of tensile strength and elongation at break - Strip method"; Peel strength: GB / T 3923.1-2013 "Textiles - Tensile properties of fabrics - Part 1: Determination of breaking strength and elongation at break - Strip method"; High and low temperature aging: GB / T 2423.1-2008 "Environmental Testing for Electrical and Electronic Products - Part 2"; Pilling: GB / T 4802.1-2008 "Textiles - Testing for Pilling - Part 1: Circular Trajectory Method"; Formaldehyde content: GB / T 2912.1-2009 "Textiles - Determination of formaldehyde - Part 1: Free and hydrolyzed formaldehyde (water extraction method)" Example 1 The preparation method adopts the process in the above embodiments, wherein the polyester substrate layer is selected with a strength of 280 g / m². 2 High-density polyester fiber woven fabric with a gradient composite coating total dry film thickness of 40μm (adhesive bottom layer 9μm, elastic intermediate layer 18μm, abrasion-resistant surface layer 13μm), and an overall fabric thickness of 1.3mm. The hydroxyl-terminated polydimethylsiloxane resin has a molecular weight of 130,000. The mass ratio of hydroxyl-terminated polydimethylsiloxane resin to KH-560 is 97:3. The crosslinking agent is hexamethylene diisocyanate trimer, which is added at 2% of the total resin mass. The dispersant is added at 0.5% of the total resin mass. The viscosity of the resin slurry is adjusted to 2800 cP. The substrate consists of modified silicone resin, titanium dioxide filler, and photocrosslinking agent in a mass ratio of 90:9:1; the elastic intermediate layer consists of modified silicone resin, polydimethylsiloxane (PDMS) elastomer, and ultraviolet absorber in a mass ratio of 40:60:1; and the wear-resistant surface layer consists of modified silicone resin and nano-silicon carbide particles in a mass ratio of 92:8. The wear-resistant surface layer contains nano-silicon carbide particles with a diameter of 80 nm. After ultrasonic dispersion, the agglomerated particle size is controlled to ≤180 nm. The nitrogen flow rate at the three-station UV curing stage is stabilized at 18 L / min, and the irradiation intensity of each stage is 800 mJ / cm². 2 1000mJ / cm 2 600mJ / cm 2 .

[0027] Finished product testing: After 50,000 Martindale rubbing tests, the coating remained intact without peeling or fuzzing; the tensile strength retention rate was 87%; the peel strength was 5.8 N / 25 mm; there was no cracking at -30℃; there was no odor at 80℃; and the formaldehyde release was 0.018 mg / m³. 3 It has a pilling rating of 4.5 and all performance characteristics meet the requirements of high-end automotive interiors.

[0028] Example 2 Compared with Example 1, this implementation differs only in the following aspects: ① The molecular weight of the hydroxyl-terminated polydimethylsiloxane resin was adjusted to 140,000; ② The particle size of the wear-resistant surface nano-silicon carbide particles was adjusted to 60 nm; ③ The irradiation intensity of the first stage of UV curing was adjusted to 850 mJ / cm². 2 The remaining process parameters, coating thickness, etc. are completely consistent with those in Example 1.

[0029] Finished product testing results: After 50,000 Martindale rubbing tests, the coating remained intact without peeling or fuzzing, with a tensile strength retention rate of 87% and a peel strength of 5.6 N / 25 mm; after aging at 80℃ for 24 hours, the peel strength retention rate was 82%, the surface showed no yellowing or irritating odor, and the formaldehyde release was 0.019 mg / m³. 3 The pilling level is 4, and all performance characteristics meet the requirements of high-end automotive interiors, proving that the process of this invention has good stability.

[0030] Example 3 Compared with Example 1, this implementation differs only in the following ways: ① The total dry film thickness of the gradient composite coating is adjusted to 42 μm, with the corresponding thicknesses of the bottom layer (10 μm), the elastic intermediate layer (20 μm), and the wear-resistant surface layer (12 μm); ② The molecular weight of the hydroxyl-terminated polydimethylsiloxane resin is adjusted to 120,000; ③ The particle size of the nano-silicon carbide particles in the wear-resistant surface layer is adjusted to 100 nm; ④ The irradiation intensity of the second stage of UV curing is adjusted to 1050 mJ / cm². 2⑤ The Shore hardness of the PDMS elastomer in the elastic intermediate layer was adjusted to 55A; the remaining process parameters, coating thickness, etc., were completely consistent with those in Example 1.

[0031] Finished product testing results: After 50,000 Martindale rubbing tests, the coating remained intact without peeling or fuzzing; the tensile strength retention rate was 86%, and the peel strength was 5.7 N / 25 mm; after 10 cycles of high and low temperature aging from -30℃ to 80℃, the peel strength retention rate was 81%, the surface showed no yellowing or deformation, and the formaldehyde release was 0.019 mg / m³. 3 The pilling level is 4, which meets the performance requirements of high-end automotive interiors, verifying that the process parameters of this invention have broad applicability.

[0032] Comparative Example 1 This comparative example uses a traditional polyurethane coating process to prepare automotive fabric. Compared with Example 1, the main differences are as follows: ① There is no gradient coating structure. A single polyurethane coating (dry film thickness 40μm) is used instead of a gradient composite coating. Specifically, it is Stahl XF series polyurethane from Stahl Fine Coatings (Suzhou) Co., Ltd. The same precision scraper coating method as the wear-resistant surface layer in Example 1 is used; ② There is no silicone modification and "anchoring-crosslinking" process. A traditional thermosetting process (curing at 120℃ for 20min) is used instead of three-wavelength UV gradient curing; only the substrate and its pretreatment steps are consistent with Example 1 to ensure a unified comparison benchmark.

[0033] Performance test results: After 50,000 Martindale rubbing tests, the coating showed obvious peeling and fuzzing, with a tensile strength retention rate of only 62% and a peel strength of 2.8 N / 25 mm; the coating became brittle at -30℃ and released a slight irritating odor at 80℃, with a formaldehyde release of 0.05 mg / m³. 3 The pilling level is 2, which cannot meet the requirements of high-end automotive interiors for durability, environmental friendliness, and adaptability to extreme environments.

[0034] Comparative Example 2 Compared with Example 1, this comparative example has the following differences: ① the substrate, gradient coating structure, thickness of each layer, and all process parameters are completely consistent with those of Example 1; ② the silicone resin was not modified by "chain extension-crosslinking", and hydroxyl-terminated polydimethylsiloxane resin was directly used to prepare the slurry of each layer, thus eliminating interference from other factors.

[0035] Performance test results: After 50,000 Martindale rubbing tests, the coating edges showed obvious lifting, the tensile strength retention rate was 73%, and the peel strength was 3.5 N / 25 mm. After high and low temperature aging, the peel strength retention rate dropped to 65%, which, although better than the traditional polyurethane fabric in Comparative Example 1, was significantly lower than the product performance of Examples 1-3. These results demonstrate that "anchoring-crosslinking" modification can effectively strengthen the chemical bond between the resin and the substrate and the stability of the interlayer structure, and is a core technology for improving the fabric's rubbing resistance and environmental adaptability.

[0036] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

[0037] Any aspects of this invention not described in detail are well-known to those skilled in the art.

Claims

1. A rub-resistant silicone-based automotive fabric, characterized in that: The fabric consists of a polyester base layer, an adhesive underlayer, an elastic intermediate layer, and an abrasion-resistant surface layer from bottom to top. The thickness percentages of each layer are as follows: polyester base layer 85-90%, adhesive underlayer 2-3%, elastic intermediate layer 4-6%, and abrasion-resistant surface layer 3-5%. The polyester substrate layer is made of woven polyester fiber fabric, and the side that contacts the substrate is pretreated in preparation for bonding with the substrate. The substrate, by weight, includes 80-100 parts modified silicone resin, 8-10 parts titanium dioxide filler, and 1-1.5 parts photocrosslinking agent, with a dry film thickness of 8-10 μm. The elastic intermediate layer, by mass parts, includes 30-50 parts of modified silicone resin, 50-70 parts of polydimethylsiloxane elastomer, and 1 part of ultraviolet absorber, wherein the total amount of modified silicone resin and polydimethylsiloxane elastomer is 100 parts, and the dry film thickness of the coating is 15-20 μm. The wear-resistant surface layer, by weight, includes 90-95 parts of modified silicone resin and 5-10 parts of nano-silicon carbide particles, with a dry film thickness of 12-15 μm. The modified organosilicon resins are all hydroxyl-terminated organosilicon resins. They first undergo a chain extension reaction with an aminosilane coupling agent to introduce amino anchoring groups, and then undergo a cross-linking reaction with an isocyanate cross-linking agent to form a three-dimensional network molecular structure.

2. The abrasion-resistant silicone-based automotive fabric according to claim 1, characterized in that: The woven polyester fiber fabric has a basis weight of 260–300 g / m². 2 The pretreatment includes degreasing, mechanical roughening, and plasma activation. The surface roughness is controlled at 1.2–1.6 μm, and the water contact angle is ≤30°.

3. The abrasion-resistant silicone-based automotive fabric according to claim 1, characterized in that: The hydroxyl-terminated silicone resin is a hydroxyl-terminated polydimethylsiloxane resin with a molecular weight of 120,000 to 150,000. The aminosilane coupling agent is KH-560, and the mass ratio of the two is (95-98):(2-5). The amount of isocyanate crosslinking agent added is 1.5-2.5% of the total mass of the modified silicone resin. During the crosslinking reaction, 0.3-0.8% of the total mass of the modified silicone resin is added as a dispersant.

4. The abrasion-resistant silicone-based automotive fabric according to claim 1, characterized in that: The photocrosslinking agent is 1-hydroxycyclohexylphenyl ketone, the titanium dioxide filler has a particle size of 1-3 μm, the solid content of the underlying slurry is controlled at 55%±2%, the polydimethylsiloxane elastomer has a Shore hardness of 50-60A, the ultraviolet absorber is UV-327, and the nano-silicon carbide particles have a particle size of 50-100 nm.

5. The abrasion-resistant silicone-based automotive fabric according to claim 1, characterized in that: The fabric has an overall thickness of 1.2 to 1.5 mm. After 50,000 Martindale rubbing tests, the coating remains intact, without peeling or pilling, and the pilling level is not lower than level 4. The tensile strength retention rate is ≥85%.

6. The method for preparing the abrasion-resistant silicone-based automotive fabric according to any one of claims 1 to 5, characterized in that, Includes the following steps: 1) The polyester substrate layer is subjected to degreasing, mechanical roughening, and plasma activation pretreatment in sequence; 2) Synthesis of modified organosilicon resin: Hydroxyl-terminated organosilicon resin and aminosilane coupling agent were reacted under nitrogen protection, at 75±2℃ and 300~500r / min with constant stirring until the chain extension reaction was completed; after adding isocyanate crosslinking agent, the temperature was raised to 85±2℃ and the reaction was continued at a constant temperature until 1720cm -1 The reaction was stopped when the characteristic absorption peak of urethane ester appeared nearby. A dispersant was added to adjust the rotational viscosity of the slurry to 2800–3200 cP. 3) Gradient coating slurry preparation: Prepare the adhesion base layer, elastic intermediate layer, and wear-resistant surface layer slurries according to the specified proportions, and disperse them evenly. 4) Coating each layer sequentially onto the polyester substrate layer. The underlayer is coated with high-pressure airless spraying. After coating, it is pre-baked to remove volatile components from the slurry while retaining the coating's tackiness. The elastic intermediate layer is coated with rollers. After coating, it is pre-baked to achieve initial interlayer bonding. The abrasion-resistant surface layer is coated with a precision doctor blade. After coating, the coating temperature is kept at a suitable temperature to prevent slurry from dripping or clumping. 5) The coated fabric undergoes a three-stage UV curing process under nitrogen protection. The first stage uses UV light with a wavelength of 320nm and an irradiation intensity of 800±50mJ / cm². 2 The curing time is 1.5–2.5 min, the second stage of ultraviolet light wavelength is 365 nm, and the irradiation intensity is 1000 ± 50 mJ / cm². 2 The curing time is 2.5–3.5 min, the wavelength of the third ultraviolet light is 395 nm, and the irradiation intensity is 600 ± 50 mJ / cm². 2 The curing time is 0.5–1.5 min, and the gel rate of the cured coating is ≥95%. 6) After curing, the product is obtained by hot pressing and surface treatment.

7. The preparation method according to claim 6, characterized in that: The pretreatment includes first immersing the polyester substrate layer in a neutral degreasing agent solution at 50±2℃ for 20 minutes, with a bath ratio of 1:20, and using ultrasonic power of 200W to assist in degreasing, removing oil, wax, and impurities from the substrate surface; then performing double-sided mechanical roughening treatment with 120-grit white corundum sandpaper, controlling the sanding rate at 1.5m / min; finally, placing it in a plasma treatment device and treating it for 30 seconds under an argon atmosphere with a power of 300W; and finally, placing the pretreated substrate in a standard environment and letting it stand for 30 minutes to eliminate surface stress.

8. The preparation method according to claim 6, characterized in that: The slurry of the attached bottom layer is dispersed in a high-speed disperser at 2000 r / min for 20 min, and then ground by a three-roll mill with a gap of 5-10 μm; the slurry of the elastic intermediate layer is dispersed in an ultrasonic disperser for 15 min at a power of 500 W, and then stirred at a constant temperature of 60°C and 300 r / min for 10 min; the slurry of the wear-resistant surface layer is first dispersed in a high-speed disperser at 3000 r / min for 30 min, and then dispersed in an ultrasonic disperser for 20 min at a power of 800 W, controlling the agglomeration particle size of the nanoparticles to be ≤200 nm.

9. The preparation method according to claim 6, characterized in that: The spraying pressure of the substrate is 0.5MPa±0.05MPa, the distance between the spray gun and the substrate is 250mm±10mm, the spraying rate is 1.2m / min, and it is pre-baked at 60±2℃ for 3min after coating; the elastic intermediate layer is coated by roller coating with two rollers, the roller speed ratio is 1:1.5, the coating pressure is 0.1MPa, and it is pre-baked at 70±2℃ for 2min after coating; the gap between the doctor blades for coating the wear-resistant surface layer is 20μm±2μm, the coating speed is 1.5m / min, and the coating temperature is maintained at 40±5℃ after coating.

10. The preparation method according to claim 6, characterized in that, In step 6): the hot pressing is performed at a temperature of 120±2℃ and a pressure of 0.2±0.02MPa for 5 minutes; the surface treatment is performed by spraying with a fluorinated silane finishing agent and then drying.