Preparation method and application of environment-friendly water-based synthetic leather

Abstract

The invention discloses a preparation method and application of environment-friendly water-based synthetic leather, and relates to the technical field of high polymer materials. The raw materials comprise o-nitrobenzyl perfluorobutyl sulfonate, a wetting agent, a dispersing agent, vinyl modified silicon dioxide, a nanocellulose suspension, acrylic acid modified epoxy resin, waterborne polyurethane, a coalescing agent, a flatting agent and a defoaming agent; the production process comprises the following steps: 1) pretreatment; 2) a coating process; (3) photo-thermal synergistic curing; according to the preparation method, a novel photo-response cross-linking agent of o-nitrobenzyl perfluorobutyl sulfonate is synthesized firstly, and then the photo-response cross-linking agent is used for preparing the environment-friendly water-based synthetic leather. Through light-triggered ionic crosslinking, dynamic by-product conversion and solid component embedding, the high-strength, ultralow-VOC, stain-resistant and flame-retardant green synthetic leather is synchronously realized, and the performance and environmental protection bottlenecks of a traditional water-based system are broken through.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and in particular to a preparation method of environmentally friendly water-based synthetic leather and application thereof. Background Art

[0002] Reducing VOC requires reducing functional additives, which leads to a sharp drop in mechanical properties. Traditional fluorocarbon additives migrate to the surface to improve water resistance, but will hinder the cross-linking reaction. Multi-layer coatings require repeated drying, which consumes a lot of energy and is prone to interface defects.

[0003] Therefore, how to produce an environmentally friendly water-based synthetic leather that has mechanical properties comparable to traditional solvent-based synthetic leather while being more environmentally friendly and safe, and has strong hydrolysis resistance and is not easy to age is the current direction of research on new synthetic leather. Summary of the Invention

[0004] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a preparation method and application of an environmentally friendly water-based synthetic leather.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] The present invention first proposes an environmentally friendly water-based synthetic leather, comprising the following raw materials:

[0007] 60-70 parts of waterborne polyurethane;

[0008] 0.5-1.1 parts of wetting agent;

[0009] 1-1.4 parts of dispersant;

[0010] 5-7 parts of nanocellulose suspension;

[0011] 5-8 parts of vinyl-modified silica;

[0012] 15-21 parts of acrylic acid modified epoxy resin;

[0013] 0.3-0.5 parts of leveling agent;

[0014] 0.2-0.5 parts of defoaming agent;

[0015] 3-5 parts of film-forming aid;

[0016] 5-8 parts of o-nitrobenzyl perfluorobutanesulfonate;

[0017] Preferably, the preparation process of o-nitrobenzyl perfluorobutanesulfonate comprises the following steps:

[0018] In a dry reaction flask, dissolve o-nitrobenzyl alcohol in anhydrous dichloromethane; cool to 0°C in an ice bath, add triethylamine with stirring; slowly add perfluorobutanesulfonyl chloride dropwise, remove the ice bath after completion, and react at room temperature for 12 hours. After the reaction is complete, quench with ice water and separate the layers.

[0019] The organic phase was washed with 1 mol / L aqueous HCl, saturated NaHCO3 solution, and water, dried over anhydrous MgSO4, filtered, and concentrated under reduced pressure to obtain a crude product of o-nitrobenzyl perfluorobutanesulfonate;

[0020] The crude o-nitrobenzyl perfluorobutanesulfonate product was purified by silica gel column chromatography using a 5:1 volume ratio of petroleum ether to ethyl acetate as eluent to obtain a light yellow oil, i.e. o-nitrobenzyl perfluorobutanesulfonate.

[0021]

[0022] The molar ratio of o-nitrobenzyl alcohol, triethylamine and perfluorobutanesulfonyl chloride is 1:1.2:1.1.

[0023] The perfluorobutane sulfonate molecule contains a photosensitive o-nitrobenzyl group and a hydrophobic perfluoro chain. In the subsequent emulsification stage, the hydrophobic component will be wrapped into the interior of the WPU particles during high-speed shearing at 5000 rpm. The perfluoro chain segment points to the hydrophobic core and is positioned in the interface layer through the weak hydrogen bond between the sulfonate group and the polyurethane urea group.

[0024] Preferably, the anhydrous dichloromethane used in the preparation process of o-nitrobenzyl perfluorobutanesulfonate is distilled in a distillation tower and then recovered and reused.

[0025] The present invention also provides a method for preparing an environmentally friendly water-based synthetic leather, comprising the following steps:

[0026] S1. Preprocessing

[0027] Add vinyl-modified silica and deionized water to the reactor, adjust the solid content to 30%, and add a wetting agent and a dispersant while stirring at 400 rpm;

[0028] When a stable vortex is formed in the reactor, a nanocellulose suspension with a solid content of 5% is slowly added along the reactor wall and dispersed at a high speed of 2000 rpm for 30 min to obtain a SiO2 mixed solution;

[0029] The SiO2 mixture was ground using a sand mill until D50 was ≤ 18 nm; after cooling, a SiO2 suspension was obtained;

[0030] Add waterborne polyurethane, acrylic modified epoxy resin, and film-forming aid, stir at 600 rpm for 30 min, and test the viscosity, which is required to be 2500 ± 300 mPa·s;

[0031] Immediately inject o-nitrobenzyl perfluorobutane sulfonate, leveling agent, and defoamer under light-proof conditions, and stir at 300 rpm for 10 minutes to obtain a coating slurry. The surface of the coating slurry has a uniform pearl luster and is free of bubbles and scum, and then enters the coating process;

[0032] S2, coating process

[0033] Acrylic-based, 180g / m 2 , a microfiber non-woven fabric with a thickness of 0.8±0.1mm was used as the substrate, infrared preheating was performed at 80℃ for 120s, the moisture adsorbed on the microfiber non-woven fabric was evaporated to make the moisture content ≤0.5%, and the microfiber non-woven fabric was subjected to plasma treatment with an air medium at a power of 2kW to obtain a pretreated non-woven fabric;

[0034] The bottom layer was coated by dip roller coating, and a 0.25 mm thick wet film was applied to the pretreated non-woven fabric, followed by hot air drying at 80°C for 120 seconds. The second layer was coated by micro-gravure transfer coating, and a 0.18 mm thick wet film was applied, followed by hot air drying at 90°C for 60 seconds to obtain coated synthetic leather.

[0035] S3, light-heat synergistic curing

[0036] The coated synthetic leather was photocured using an LED array with a peak wavelength of 250 ± 5 nm, and the irradiation intensity was set to 120 mW / cm 2 , irradiation distance 10cm, transmission speed 1.2m / s, exposure time 5 seconds;

[0037]

[0038] Photocatalytic decomposition of o-nitrosobenzyl perfluorobutanesulfonate to generate o-nitrosobenzaldehyde and perfluorobutanesulfonic acid;

[0039] Perfluorobutane sulfonic acid, as a strong proton acid, catalyzes the ring-opening of the epoxy groups in acrylic modified epoxy resin, initiating cationic polymerization and forming a cross-linked network. At the same time, its sulfonate groups form strong ionic bonds with the -NH- groups in the polyurethane urea chain, anchoring them to the WPU molecular chains through ionic bonds, thereby enhancing the tensile strength of the product. Furthermore, since the fluoride ion is a hydrophobic and inert group, it is encapsulated within the WPU particles. Its low surface energy drives the fluorine chains toward the hydrophobic core, forming a dense fluorocarbon layer that is directionally arranged at the particle interface, forming a hydrophobic barrier that physically blocks the penetration of water molecules, thereby increasing solvent resistance, stain resistance, and flame retardancy.

[0040]

[0041] After self-coupling, o-nitrosobenzaldehyde undergoes Norrish I-type cleavage under the influence of light to produce benzoyl radicals and nitroso radicals. These radicals can initiate the polymerization of vinyl silica to form an inorganic-organic hybrid cross-linked structure. In the subsequent curing process, they are connected to the polyurethane chain through a high-temperature neutralization reaction, or undergo an addition reaction with the epoxy acrylate prepolymer obtained by ring-opening of the acrylic modified epoxy resin.

[0042] The coated synthetic leather after light curing was heat cured using a three-zone hot air circulation drying tunnel. The temperature curve was set as 60±5°C in zone 1, with a dwell time of 40s; 100±2°C in zone 2, with a dwell time of 60s; and 80±3°C in zone 3, with a dwell time of 20s. The wind speed was controlled at 2m / s.

[0043] Thermal curing promotes the reaction of hydroxyl groups generated by epoxy ring-opening polymerization with -NCO groups in the polyurethane chain, the free radical polymer of vinyl silica is connected with the ester bond of acrylic modified epoxy resin, and the perfluorobutyl sulfonic acid ion bond is further stabilized and coordinated at high temperature.

[0044] The water-based synthetic leather obtained after thermal curing is the product.

[0045] Preferably, in S1, the coating process needs to ensure that the residual moisture between layers is ≤8%, and the total coating amount is 60±5g / m 2 .

[0046] Preferably, the wetting agent is polyether-modified polysiloxane; the dispersant is DISPERBYK-2155; the defoaming agent is a mineral oil / polyether complex; the film-forming aid is dipropylene glycol butyl ether; and the leveling agent is BYK-333.

[0047] The environmentally friendly water-based synthetic leather prepared by the preparation method proposed in the present invention is suitable for the fields of high-end shoes, bags, and furniture decoration.

[0048] Compared with the prior art, the present invention has the following beneficial effects:

[0049] The present invention realizes the core component linkage mechanism and performance gain by designing a photosensitive crosslinking agent o-nitrobenzyl perfluorobutane sulfonate.

[0050] Specifically, the perfluorobutanesulfonic acid produced by the decomposition of the photosensitive crosslinker forms a strong ionic bond with the urea groups in the waterborne polyurethane molecular chain. It also catalyzes the ring-opening polymerization of the acrylic-modified epoxy resin and interpenetrates with the nanocellulose-vinyl silica hybrid network, creating a three-dimensional crosslinked structure that is both rigid and flexible. This synergistic effect significantly enhances the tensile strength, elongation at break, tear resistance, and resilience of the synthetic leather.

[0051] After photolysis, the perfluorobutyl chains migrate directionally to the coating's surface, where their ultra-low surface energy drives the formation of a dense fluorocarbon barrier. The micro- and nano-rough surface constructed by nanocellulose and silica synergizes with the fluorocarbon chains to form a Cassie-Baxter hydrophobic structure, achieving a self-cleaning effect. It resists everyday stains, especially oily ones, and exhibits strong anti-fouling properties.

[0052] The dense fluorocarbon layer physically blocks the penetration of corrosive media, the sulfonate ion bond enhances the acid and alkali resistance of the coating, and the highly cross-linked IPN network inhibits solvent swelling.

[0053] During combustion, nanocellulose carbonizes and forms a Si-OC ceramic layer with vinyl silica, isolating oxygen (condensed phase flame retardant); the perfluoro chain decomposes under heat to release free radical quenchers such as PF3, interrupting the combustion chain reaction (gas phase flame retardant); and has excellent fire resistance.

[0054] In summary, the present invention achieves high-strength, ultra-low VOC, stain-resistant and flame-retardant green synthetic leather through light-triggered ionic crosslinking, dynamic by-product conversion, and solid-state component intercalation, breaking through the performance and environmental protection bottlenecks of traditional water-based systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 The figure is the nuclear magnetic hydrogen spectrum of o-nitrobenzyl perfluorobutane sulfonate produced by the present invention. DETAILED DESCRIPTION

[0056] The following will be combined with the accompanying drawings in the embodiments of the present invention. Figure 1 As shown, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0057] The purity of the drugs used in the experiment and their manufacturers are shown in Table 1:

[0058] Table 1. Raw material drug information

[0059]

[0060] Example 1:

[0061] S1. Preprocessing

[0062] Add 8 kg of vinyl-modified silica and deionized water to the reactor, adjust the solid content to 30%, and add 0.5 kg of wetting agent and 1.4 kg of dispersant while stirring at 400 rpm;

[0063] When a stable vortex is formed in the reactor, 7 kg of nanocellulose suspension with a solid content of 5% is slowly added along the reactor wall and dispersed at a high speed of 2000 rpm for 30 min to obtain a SiO2 mixed solution;

[0064] The SiO2 mixture was ground using a sand mill until D50 was ≤ 18 nm; after cooling, a SiO2 suspension was obtained;

[0065] Add 60 kg of waterborne polyurethane, 15 kg of acrylic modified epoxy resin, and 5 kg of film-forming aid, stir at 600 rpm for 30 min, and test the viscosity, which is required to be 2500 ± 300 mPa·s;

[0066] Immediately inject 8 kg of o-nitrobenzyl perfluorobutyl sulfonate, 0.5 kg of leveling agent, and 0.2 kg of defoamer under light-proof conditions, and stir at 300 rpm for 10 minutes to obtain a coating slurry. The surface of the coating slurry has a uniform pearl luster and is free of bubbles and scum, and then enters the coating process;

[0067] S2, coating process

[0068] Acrylic-based, 180g / m 2 , a microfiber non-woven fabric with a thickness of 0.8±0.1mm was used as the substrate, infrared preheating was performed at 80℃ for 120s, the moisture adsorbed on the microfiber non-woven fabric was evaporated to make the moisture content ≤0.5%, and the microfiber non-woven fabric was subjected to plasma treatment with an air medium at a power of 2kW to obtain a pretreated non-woven fabric;

[0069] The bottom layer was coated by dip roller coating, and a 0.25 mm thick wet film was applied to the pretreated non-woven fabric, followed by hot air drying at 80°C for 120 seconds. The second layer was coated by micro-gravure transfer coating, and a 0.18 mm thick wet film was applied, followed by hot air drying at 90°C for 60 seconds to obtain coated synthetic leather.

[0070] S3, light-heat synergistic curing

[0071] The coated synthetic leather was photocured using an LED array with a peak wavelength of 250 ± 5 nm, and the irradiation intensity was set to 120 mW / cm 2 , irradiation distance 10cm, transmission speed 1.2m / s, exposure time 5 seconds;

[0072] The coated synthetic leather after light curing was heat cured using a three-zone hot air circulation drying tunnel. The temperature curve was set as 60±5°C in zone 1, with a dwell time of 40s; 100±2°C in zone 2, with a dwell time of 60s; and 80±3°C in zone 3, with a dwell time of 20s. The wind speed was controlled at 2m / s.

[0073] The water-based synthetic leather obtained after thermal curing is the product.

[0074] Example 2

[0075] S1. Preprocessing

[0076] Add 6.5 kg of vinyl-modified silica and deionized water to the reactor, adjust the solid content to 30%, and add 0.8 kg of wetting agent and 1.25 kg of dispersant while stirring at 400 rpm;

[0077] When a stable vortex is formed in the reactor, 6 kg of nanocellulose suspension with a solid content of 5% is slowly added along the reactor wall and dispersed at a high speed of 2000 rpm for 30 min to obtain a SiO2 mixed solution;

[0078] The SiO2 mixture was ground using a sand mill until D50 was ≤ 18 nm; after cooling, a SiO2 suspension was obtained;

[0079] Add 65 kg of waterborne polyurethane, 18 kg of acrylic modified epoxy resin, and 4 kg of film-forming aid, stir at 600 rpm for 30 min, and test the viscosity, which is required to be 2500 ± 300 mPa·s;

[0080] Immediately inject 6.5 kg of o-nitrobenzyl perfluorobutyl sulfonate, 0.4 kg of leveling agent, and 0.35 kg of defoamer under light-proof conditions, and stir at 300 rpm for 10 minutes to obtain a coating slurry. The surface of the coating slurry has a uniform pearl luster and is free of bubbles and scum, and then enters the coating process;

[0081] S2, coating process

[0082] Acrylic-based, 180g / m 2 , a microfiber non-woven fabric with a thickness of 0.8±0.1mm was used as the substrate, infrared preheating was performed at 80℃ for 120s, the moisture adsorbed on the microfiber non-woven fabric was evaporated to make the moisture content ≤0.5%, and the microfiber non-woven fabric was subjected to plasma treatment with an air medium at a power of 2kW to obtain a pretreated non-woven fabric;

[0083] The bottom layer was coated by dip roller coating, and a 0.25 mm thick wet film was applied to the pretreated non-woven fabric, followed by hot air drying at 80°C for 120 seconds. The second layer was coated by micro-gravure transfer coating, and a 0.18 mm thick wet film was applied, followed by hot air drying at 90°C for 60 seconds to obtain coated synthetic leather.

[0084] S3, light-heat synergistic curing

[0085] The coated synthetic leather was photocured using an LED array with a peak wavelength of 250 ± 5 nm, and the irradiation intensity was set to 120 mW / cm 2 , irradiation distance 10cm, transmission speed 1.2m / s, exposure time 5 seconds;

[0086] The coated synthetic leather after light curing was heat cured using a three-zone hot air circulation drying tunnel. The temperature curve was set as 60±5°C in zone 1, with a dwell time of 40s; 100±2°C in zone 2, with a dwell time of 60s; and 80±3°C in zone 3, with a dwell time of 20s. The wind speed was controlled at 2m / s.

[0087] The water-based synthetic leather obtained after thermal curing is the product.

[0088] Example 3

[0089] S1. Preprocessing

[0090] Add 5 kg of vinyl-modified silica and deionized water to the reactor, adjust the solid content to 30%, and add 1.1 kg of wetting agent and 1 kg of dispersant while stirring at 400 rpm;

[0091] When a stable vortex is formed in the reactor, 5 kg of nanocellulose suspension with a solid content of 5% is slowly added along the reactor wall and dispersed at a high speed of 2000 rpm for 30 min to obtain a SiO2 mixed solution;

[0092] The SiO2 mixture was ground using a sand mill until D50 was ≤ 18 nm; after cooling, a SiO2 suspension was obtained;

[0093] Add 70 kg of waterborne polyurethane, 21 kg of acrylic modified epoxy resin, and 3 kg of film-forming aid, stir at 600 rpm for 30 min, and test the viscosity, which is required to be 2500 ± 300 mPa·s;

[0094] Immediately inject 5 kg of o-nitrobenzyl perfluorobutyl sulfonate, 0.3 kg of leveling agent, and 0.5 kg of defoamer under light-proof conditions, and stir at 300 rpm for 10 minutes to obtain a coating slurry. The surface of the coating slurry has a uniform pearl luster and is free of bubbles and scum, and then enters the coating process;

[0095] S2, coating process

[0096] Acrylic-based, 180g / m 2 , a microfiber non-woven fabric with a thickness of 0.8±0.1mm was used as the substrate, infrared preheating was performed at 80℃ for 120s, the moisture adsorbed on the microfiber non-woven fabric was evaporated to make the moisture content ≤0.5%, and the microfiber non-woven fabric was subjected to plasma treatment with an air medium at a power of 2kW to obtain a pretreated non-woven fabric;

[0097] The bottom layer was coated by dip roller coating, and a 0.25 mm thick wet film was applied to the pretreated non-woven fabric, followed by hot air drying at 80°C for 120 seconds. The second layer was coated by micro-gravure transfer coating, and a 0.18 mm thick wet film was applied, followed by hot air drying at 90°C for 60 seconds to obtain coated synthetic leather.

[0098] S3, light-heat synergistic curing

[0099] The coated synthetic leather was photocured using an LED array with a peak wavelength of 250 ± 5 nm, and the irradiation intensity was set to 120 mW / cm 2 , irradiation distance 10cm, transmission speed 1.2m / s, exposure time 5 seconds;

[0100] The coated synthetic leather after light curing was heat cured using a three-zone hot air circulation drying tunnel. The temperature curve was set as 60±5°C in zone 1, with a dwell time of 40s; 100±2°C in zone 2, with a dwell time of 60s; and 80±3°C in zone 3, with a dwell time of 20s. The wind speed was controlled at 2m / s.

[0101] The water-based synthetic leather obtained after thermal curing is the product.

[0102] Also designed accordingly:

[0103] Comparative Example 1: The formulation and experimental method are the same as those in Example 2, but insufficient waterborne polyurethane is added;

[0104] Comparative Example 2: The formulation and experimental method are the same as those in Example 2, but an excess of waterborne polyurethane is added;

[0105] Comparative Example 3: The formulation and experimental method are the same as those in Example 2, but insufficient o-nitrobenzyl perfluorobutanesulfonate is added;

[0106] Comparative Example 4: The formulation and experimental method are the same as those in Example 2, except that an excess of o-nitrobenzyl perfluorobutanesulfonate is added;

[0107] Comparative Example 5: The formulation and experimental method are the same as those in Example 2, but insufficient vinyl-modified silica is added;

[0108] Comparative Example 6: The formulation and experimental method are the same as those in Example 2, but an excess of vinyl-modified silica is added;

[0109] The specific formula is shown in Table 2:

[0110] Table 2. Formula of an environmentally friendly water-based synthetic leather

[0111]

[0112] According to ISO 3376:2020 "Leather - Determination of tensile strength and elongation", ISO 17074:2019 "Leather - Determination of abrasion resistance", ISO 2419:2012 "Leather - Physical test - Determination of hydrolysis resistance", GB / T 14522-2008 "Artificial weathering test methods for plastics, coatings and rubber materials for use in mechanical industrial products", GB / T 5455-2014 "Fire performance of textiles - Determination of vertical damage length, etc.", EU 2017 / 1000 PFOA-related annexes, and GB 33372-2020 "Limits of volatile organic compounds in adhesives", the present invention was tested for mechanical properties, abrasion resistance, UV aging resistance, flame retardancy, VOC emissions, perfluorinated compounds (PFAS) residues, and hydrolysis resistance.

[0113] The corresponding results and data are summarized and plotted in Table 3:

[0114] Table 3. Performance test data of water-based synthetic leather

[0115]

[0116] Data analysis shows that:

[0117] The WPU dosage in Comparative Example 1 is insufficient, the cross-linking point density is too low, the shear resistance is weak, the viscosity collapses during grinding and injection molding, and the subsequent finished product is poor. When put into use, the colloid viscosity is low and cannot adhere well to the mold.

[0118] In Comparative Example 2, the amount of waterborne polyurethane used exceeded the applicable range, and the free waterborne polyurethane destroyed the cross-linking network, resulting in a decrease in the mechanical strength of the product and a loss of film-forming continuity.

[0119] Comparative Example 3 lacks o-nitrobenzyl perfluorobutane sulfonate, resulting in significant degradation of all properties. The tensile strength is greatly reduced due to the lack of ionic bond anchoring reinforcement, the fluorocarbon-free hydrophobic barrier is difficult to form, and the hydrolysis resistance is reduced.

[0120] The o-nitrobenzyl perfluorobutane sulfonate of Comparative Example 4 had an excessive amount of residual PFOA due to incomplete reaction. Moreover, the excessive fluorine chain aggregation caused interface defects and deteriorated hydrolysis resistance.

[0121] In Comparative Examples 5 and 6, the amount of inorganic filler used exceeds the applicable range. The product lacks hard support points and has poor wear resistance. When the amount exceeds the limit, the rigidity is overloaded and the elongation decreases, but the damaged length improves.

[0122] In summary, the synthetic leather of the present invention, through light-triggered ionic crosslinking, dynamic by-product conversion, and solid-state component intercalation, simultaneously achieves high-strength, ultra-low VOC, stain-resistant and flame-retardant green synthetic leather, breaking through the performance and environmental protection bottlenecks of traditional water-based systems.

[0123] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. An environmentally friendly water-based synthetic leather, characterized in that: The invention comprises the following raw materials in parts by weight: 60-70 parts of waterborne polyurethane; 0.5-1.1 parts of wetting agent; 1-1.4 parts of dispersant; 5-7 parts of nanocellulose suspension; 5-8 parts of vinyl-modified silica; 15-21 parts of acrylic acid modified epoxy resin; 0.3-0.5 parts of leveling agent; 0.2-0.5 parts of defoaming agent; 3-5 parts of film-forming aid; 5-8 parts of o-nitrobenzyl perfluorobutanesulfonate; The preparation process of the o-nitrobenzyl perfluorobutane sulfonate comprises the following steps: In a dry reaction flask, dissolve o-nitrobenzyl alcohol in anhydrous dichloromethane; cool to 0°C in an ice bath, add triethylamine with stirring; slowly add perfluorobutanesulfonyl chloride dropwise, remove the ice bath after completion, and react at room temperature for 12 hours. After the reaction is complete, quench with ice water and separate the layers. The organic phase was washed with 1 mol / L aqueous HCl, saturated NaHCO3 solution, and water, dried over anhydrous MgSO4, filtered, and concentrated under reduced pressure to obtain a crude product of o-nitrobenzyl perfluorobutanesulfonate; The crude o-nitrobenzyl perfluorobutanesulfonate product was purified by silica gel column chromatography using a 5:1 volume ratio of petroleum ether to ethyl acetate as eluent to obtain a light yellow oil, i.e. o-nitrobenzyl perfluorobutanesulfonate. The molar ratio of o-nitrobenzyl alcohol, triethylamine and perfluorobutanesulfonyl chloride is 1:1.2:1.

1.

2. The environmentally friendly water-based synthetic leather according to claim 1, characterized in that: In the preparation process of the o-nitrobenzyl perfluorobutane sulfonate, anhydrous dichloromethane is distilled in a distillation tower and then recovered and reused.

3. A method for preparing an environmentally friendly water-based synthetic leather, for preparing an environmentally friendly water-based synthetic leather as claimed in any one of claims 1 to 2, characterized in that: The following steps are involved: S1. Preprocessing Add vinyl-modified silica and deionized water to the reactor, adjust the solid content to 30%, and add a wetting agent and a dispersant while stirring at 400 rpm; When a stable vortex is formed in the reactor, a nanocellulose suspension with a solid content of 5% is slowly added along the reactor wall and dispersed at a high speed of 2000 rpm for 30 min to obtain a SiO2 mixed solution; The SiO2 mixture was ground using a sand mill until D50 was ≤ 18 nm; after cooling, a SiO2 suspension was obtained; Add waterborne polyurethane, acrylic modified epoxy resin, and film-forming aid, stir at 600 rpm for 30 min, and test the viscosity, which is required to be 2500 ± 300 mPa·s; Immediately inject o-nitrobenzyl perfluorobutane sulfonate, leveling agent, and defoamer under light-proof conditions, and stir at 300 rpm for 10 minutes to obtain a coating slurry. The surface of the coating slurry has a uniform pearl luster and is free of bubbles and scum, and then enters the coating process; S2, coating process Acrylic-based, 180g / m 2 , a microfiber non-woven fabric with a thickness of 0.8±0.1mm was used as the substrate, infrared preheating was performed at 80℃ for 120s, the moisture adsorbed on the microfiber non-woven fabric was evaporated to make the moisture content ≤0.5%, and the microfiber non-woven fabric was subjected to plasma treatment with an air medium at a power of 2kW to obtain a pretreated non-woven fabric; The bottom layer was coated by dip roller coating, and a 0.25 mm thick wet film was applied to the pretreated non-woven fabric, followed by hot air drying at 80°C for 120 seconds. The second layer was coated by micro-gravure transfer coating, and a 0.18 mm thick wet film was applied, followed by hot air drying at 90°C for 60 seconds to obtain coated synthetic leather. S3, light-heat synergistic curing The coated synthetic leather was photocured using an LED array with a peak wavelength of 250 ± 5 nm, and the irradiation intensity was set to 120 mW / cm 2 , irradiation distance 10cm, transmission speed 1.2m / s, exposure time 5 seconds; The coated synthetic leather after light curing was heat cured using a three-zone hot air circulation drying tunnel. The temperature curve was set as 60±5°C in zone 1, with a dwell time of 40s; 100±2°C in zone 2, with a dwell time of 60s; and 80±3°C in zone 3, with a dwell time of 20s. The wind speed was controlled at 2m / s. The water-based synthetic leather obtained after thermal curing is the product.

4. The method for preparing an environmentally friendly water-based synthetic leather according to claim 3, characterized in that: In S1, the coating process must ensure that the residual moisture between layers is ≤8%, and the total coating amount is 60±5g / m 2 .

5. The method for preparing an environmentally friendly water-based synthetic leather according to claim 3, characterized in that: The wetting agent is polyether-modified polysiloxane; the dispersant is DISPERBYK-2155; the defoaming agent is a mineral oil / polyether complex; the film-forming aid is dipropylene glycol butyl ether; and the leveling agent is BYK-333.

6. The environmentally friendly water-based synthetic leather prepared by the preparation method according to claim 3 is used in the fields of high-end shoes, bags, and furniture decoration.

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