A shoe synthetic leather with persistent release of wormwood flavor and antibacterial function

Abstract

This invention discloses a synthetic leather for footwear that provides a long-lasting release of mugwort aroma and antibacterial function, belonging to the field of synthetic leather technology. The synthetic leather comprises a pre-treated non-woven fabric, a wet-laid base layer, and a functional coating layer. The wet-laid base layer is coated on the surface of the pre-treated non-woven fabric, and the functional coating layer is coated on the surface of the wet-laid base layer. Both the wet-laid base layer and the functional coating layer contain composite microcapsules. The composite microcapsules use a composition of mugwort composite core material, limonene, zeolite, and chitosan quaternary ammonium salt as the core, and an epoxy-mPHBV-sodium alginate-polyethylene glycol crosslinking system as the wall material. The synthetic leather prepared by this invention solves the problems of easy volatilization of mugwort aroma, easy loss of functional components, poor heat resistance of microcapsules, and poor functional durability in existing products. It achieves a long-lasting and stable release of mugwort aroma and antibacterial, anti-mildew, and deodorizing functions, meeting the actual needs of footwear use.

Description

Technical Field

[0001] This invention belongs to the field of synthetic leather technology, specifically relating to a synthetic leather for footwear that provides a long-lasting release of mugwort scent and antibacterial function. Background Technology

[0002] Synthetic leather for footwear is widely used in the production of uppers and linings for various types of footwear, including athletic shoes, casual shoes, and leather shoes, due to its advantages such as softness, abrasion resistance, water resistance, and ease of processing. With increasing consumer awareness of health, synthetic leather for footwear with natural fragrances, antibacterial properties, mildew resistance, and odor-eliminating functions has become a market hotspot. Artemisia argyi, as a natural herb, has essential oils with a unique aroma, and its extracts possess excellent antibacterial, mildew-eliminating, and odor-eliminating activities, making it an ideal functional additive. However, current technologies for applying the active ingredients of Artemisia argyi to synthetic leather for footwear have significant drawbacks: the processing steps of synthetic leather, such as wet coagulation, drying, and embossing, require high temperatures of 120-180℃. Artemisia argyi essential oil is prone to rapid volatilization at high temperatures, and antibacterial and antifungal active ingredients such as Artemisia argyi extract are easily oxidized, decomposed, and deactivated. Existing technologies mostly use a single capsule wall to encapsulate the active ingredients of Artemisia argyi, which can only achieve passive protection and cannot achieve the retention of active ingredients during high-temperature processing or long-term slow release during normal-temperature wear. At the same time, it is difficult to achieve the synergistic effect of the four major functions of antibacterial, antifungal, fragrance release, and odor removal, resulting in weak functions and extremely poor durability of the finished synthetic leather. The fragrance release duration is generally no more than 3 months, and the antibacterial and antifungal effects significantly decrease after 1-2 months of wear, which cannot meet the functional requirements of long-term wear of footwear.

[0003] To address the shortcomings of existing technologies, this invention provides a synthetic leather for footwear that provides a lasting release of mugwort aroma and antibacterial function, achieving a stable and long-lasting mugwort fragrance and antibacterial, anti-mildew, and deodorizing properties, and is suitable for the high-temperature processing and long-term wear requirements of synthetic leather for footwear. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a synthetic leather for footwear that offers sustained release of mugwort aroma and antibacterial properties. It utilizes a β-cyclodextrin-chitosan graft to molecularly lock in the active components of mugwort, further encapsulating them with heat-resistant composite microcapsules. Simultaneously, it incorporates synergistic functional components such as zeolite and chitosan quaternary ammonium salts. This solves the problems of volatile mugwort aroma, easy loss of functional components, microcapsules' poor heat resistance, and poor functional durability in existing products. The resulting synthetic leather can withstand high-temperature processing and maintain stable functional effects during long-term wear, achieving a sustained and stable release of mugwort aroma and antibacterial, anti-mildew, and deodorizing functions, thus meeting the practical needs of footwear use.

[0005] To solve the above technical problems, the technical solution adopted by the present invention is as follows: A synthetic leather for footwear that provides a long-lasting release of mugwort scent and antibacterial properties includes a pre-treated nonwoven fabric, a wet-laid base layer, and a functional coating layer; the wet-laid base layer is coated on the surface of the pre-treated nonwoven fabric, and the functional coating layer is coated on the surface of the wet-laid base layer; both the wet-laid base layer and the functional coating layer contain composite microcapsules. The composite microcapsule has a core-wall structure. The core of the composite microcapsule is a combination of Artemisia argyi composite core material, limonene, zeolite and chitosan quaternary ammonium salt, and the wall material is an epoxy-mPHBV-sodium alginate-polyethylene glycol crosslinking system.

[0006] The preparation method of the Artemisia argyi composite core material is as follows: disperse β-cyclodextrin-chitosan graft in water, add Artemisia argyi essential oil, stir evenly and then sonicate for 12-16 min, then add Artemisia argyi extract, adjust the stirring speed to 250-350 rpm, stir at a constant temperature of 30-35℃ for 50-70 min, and then vacuum dry at 40-50℃ to obtain Artemisia argyi composite core material. Ultrasonic treatment can induce molecular entanglement, promote the embedding of Artemisia argyi essential oil molecules into the hydrophobic cavity of the graft, form a stable inclusion complex, and change the solution from turbid to semi-transparent with no obvious oil droplets floating. The hydroxyl and amino groups in the β-cyclodextrin-chitosan graft form intermolecular hydrogen bonds with the functional components. The viscous network of chitosan will physically adsorb and fix these substances containing active groups, locking the functional components into a stable complex. The frequency of the ultrasonic treatment is 20-30kHz; The mass ratio of the β-cyclodextrin-chitosan graft, Artemisia argyi essential oil, Artemisia argyi extract, and water is 1:0.15-0.2:1.2-1.6:15-20; The Artemisia argyi extract has a particle size of 5-10 μm, and its total flavonoid content is not less than 8.0%, and its polysaccharide content is not less than 15.0%. The Artemisia argyi extract was prepared by water extraction and alcohol precipitation. During the vacuum drying process, the β-cyclodextrin-chitosan graft shrinks, which can firmly lock the essential oils and functional powders in the porous network framework formed by it, thus obtaining the composite core material.

[0007] Verification of composite effect: Take 10g of core material solution, put it into a centrifuge tube, and centrifuge at 8000rpm for 10min. No precipitation or stratification was observed, indicating that the composite is stable. The inclusion rate of Artemisia argyi active molecules can be confirmed to be ≥95% by UV-Vis spectrophotometry.

[0008] The preparation method of the β-cyclodextrin-chitosan graft is as follows: β-cyclodextrin is dissolved in a mixed solvent composed of dimethyl sulfoxide and isopropanol. Epichlorohydrin is added dropwise under stirring. After the addition is complete, the pH of the solution is adjusted to 7-8. The mixture is stirred at room temperature for 4-5 hours. Chitosan is then added to the flask. The stirring speed is maintained at 250-350 rpm. The mixture is stirred at room temperature for 4-5 hours until a uniform viscous solution is formed. After the reaction is complete, the reaction solution is filtered. The filter cake is washed with water until the pH is 6.8-7.2. It is then dried in a vacuum drying oven at 48-52℃ for 7.5-8.5 hours. After pulverizing, the product is passed through an 80-100 mesh sieve to obtain a white powdery β-cyclodextrin-chitosan graft.

[0009] The mass ratio of dimethyl sulfoxide to isopropanol in the mixed solvent is 1:0.8-1.2; The mass ratio of β-cyclodextrin, chitosan, epichlorohydrin and the mixed solvent is 1:0.8-1.2:1.2-1.5:2.2-2.6.

[0010] The preparation process of the composite microcapsules includes the preparation of wall material precursors and microcapsule molding; The method for preparing the wall material precursor is as follows: epoxy-mPHBV is added to an ethanol / water mixed solvent and stirred at 58-62℃ until completely dissolved. While keeping the temperature constant, sodium alginate oxide and PEG-4000 are added in sequence and stirred until completely dissolved. Citric acid is then added and stirred at 58-62℃ for 25-35 minutes to activate the solution and obtain a uniform and transparent wall material precursor solution. The epoxy-mPHBV is a random copolymer of 3-hydroxybutyric acid and 3-hydroxyvalerate, wherein the molar percentage of 3-hydroxyvalerate units is 12-18 mol%, the epoxy value is 0.08-0.12 eq / 100g, and the number average molecular weight is 8000-12000g / mol. The oxidized sodium alginate is sodium alginate oxidized with sodium periodate, and the aldehyde content of the oxidized sodium alginate is 0.35-0.45 mmol / g; The mass ratio of ethanol to water in the ethanol / water mixed solvent is 2.5-3:7; The mass ratio of epoxy-mPHBV, oxidized sodium alginate, PEG-4000, citric acid, and ethanol / water mixed solvent is 10:3.5-4.5:1.8-2.2:0.12-0.15:120-130.

[0011] The microcapsule forming method is as follows: water and SMA emulsifier are mixed and stirred to dissolve. A wall material precursor solution is added and mixed evenly. The temperature is maintained at 58-62℃. Then, Artemisia argyi composite core material, limonene, zeolite and chitosan quaternary ammonium salt are added. The mixture is homogenized at 7500-8500 rpm for 9-11 min. After homogenization, the reaction system is heated to 73-78℃, and epichlorohydrin is slowly added dropwise. After the addition is complete, the mixture is stirred at 300-400 rpm for 2.3-2.7 h. After the reaction is completed, the pH is adjusted to 6.8-7.2, cooled, filtered, and washed with water 3-4 times. Finally, the mixture is vacuum dried at 55-65℃ to obtain composite microcapsules. The particle size of the zeolite is 4-6 μm; The chitosan quaternary ammonium salt is 2-hydroxypropyltrimethylammonium chloride chitosan, with a degree of substitution of 60-80% and a molecular weight of 40,000-80,000 Da; The SMA emulsifier is a styrene-maleic anhydride copolymer; The mass ratio of water, SMA emulsifier, wall material precursor solution, Artemisia argyi composite core material, limonene, zeolite, chitosan quaternary ammonium salt and epichlorohydrin is 100:1-1.5:95-105:22-28:3.5-4.5:7-10:1-2:0.05-0.07; Dry, white powdery composite microcapsules were obtained, and thermogravimetric analysis showed that the 5% thermogravimetric temperature was >220℃.

[0012] Preparation method of synthetic leather for footwear: (1) Substrate pretreatment The nonwoven fabric is immersed in water at 45-55℃ for 4.5-5.5 minutes, and then dried at 75-85℃ for 2.5-3.5 minutes to obtain the pretreated nonwoven fabric. This step removes spinning oil and improves hydrophilicity.

[0013] The nonwoven fabric has a basis weight of 200-240 g / m². 2 .

[0014] (2) Preparation of wet slurry Composite microcapsules and KH-550 were added to polyurethane resin and dispersed at 1000-1200 rpm for 25-35 min to obtain wet slurry; The polyurethane resin has a solid content of 28-32 wt% and the solvent is N,N-dimethylformamide; The mass ratio of the polyurethane resin, composite microcapsules, and KH-550 is 100:5.5-6.5:0.6-0.8.

[0015] (3) Scraping and solidification The wet slurry is coated onto the pretreated nonwoven fabric, and then immersed in a coagulation bath at 23-27℃ for 14-16 minutes to form a porous wet base layer rich in microcapsules. The thickness of the wet slurry coating is 0.33-0.37 mm; The coagulation bath is an N,N-dimethylformamide solution with a concentration of 18-22 wt%.

[0016] (4) Washing and drying Wash thoroughly with running water to remove N,N-dimethylformamide, and then dry at 95-105℃ for 4-5 minutes.

[0017] (5) Formulation of functional coating layer Take the water-based coating agent, add the composite microcapsules and KH-550, and stir at 350-450 rpm for 15-25 minutes; The mass ratio of the water-based coating agent, composite microcapsules, and KH-550 is 100:3.8-4.2:0.4-0.6.

[0018] (6) Coating and drying The coating agent is applied to the base surface using a roller coating method, with a liquid concentration of 75-85 g / m². 2 Then dry at 105-115℃ for 1.8-2.2 minutes.

[0019] This step can form a dense, microcapsule-containing protective film on the surface.

[0020] (7) Low-temperature embossing Using an embossing machine, emboss for 28-32 seconds at 120-130℃ and 1.8-2.2MPa pressure.

[0021] (8) Post-processing After being hung and cured at room temperature for 22-26 hours, the product is inspected and cut to obtain the finished synthetic leather for footwear.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention uses β-cyclodextrin-chitosan graft as a molecular locking agent. The hydrophobic cavity in its molecular structure can be precisely embedded into Artemisia argyi essential oil molecules. At the same time, the hydroxyl and amino groups in the graft can form intermolecular hydrogen bonds with the flavonoids and polysaccharides in Artemisia argyi extract, fixing the active ingredients through a dual action of physical adsorption and chemical binding. Then, it is combined with the epoxy-mPHBV-sodium alginate-polyethylene glycol system wall material for secondary encapsulation, forming a double locking structure, which can effectively reduce the volatilization and loss of Artemisia argyi active ingredients during high-temperature processing and use, extend its functional period, and avoid rapid decay of active ingredients.

[0023] β-Cyclodextrin-chitosan grafts, as molecular locking agents, have a dual response mechanism to humidity and temperature. Chitosan has strong hydrophilicity and swelling properties. Foot sweat causes chitosan chains to swell, physically expanding the cyclodextrin cavity and accelerating the release of essential oils. When worn, the temperature rises in the feet, promoting the movement of chitosan chain segments, which is also conducive to release.

[0024] 2. In terms of antibacterial and antifungal properties, the product utilizes the synergistic effects of mugwort extract, chitosan quaternary ammonium salt, and zeolite. The flavonoids and polysaccharides in the mugwort extract have natural antibacterial properties, while zeolite can adsorb odor molecules and synergistically inhibit bacteria. The cationic properties of chitosan quaternary ammonium salt can adsorb bacteria and inhibit their reproduction. The combination of these three components broadens the antibacterial spectrum and enhances the antibacterial effect. At the same time, it can inhibit the germination of mold spores, avoiding the problem of mold growth in shoes after long-term wear. In terms of deodorization, the mugwort extract and zeolite can synergistically decompose odor molecules such as ammonia and acetic acid produced by the feet, rather than simply masking them. This prevents the generation of secondary odors, meeting the needs of closed-fitting footwear and improving wearing comfort.

[0025] 3. The wall material of the composite microcapsules is formed by cross-linking and curing epoxy-mPHBV-sodium alginate-polyethylene glycol. Thermogravimetric analysis shows that its 5% thermal weight loss temperature is >220℃, which is much higher than the drying and embossing process temperature of 105-130℃ in the preparation of synthetic leather. This can prevent the microcapsules from softening and breaking due to high temperature during processing. β-cyclodextrin-chitosan grafts act as molecular locking agents, forming intermolecular hydrogen bonds with antibacterial components, locking the active ingredients into a stable complex. Even if the capsule wall experiences minor damage at high temperatures, it can prevent the loss of active ingredients, achieving molecular-level activation and forming a double protection with the capsule wall, completely solving the problem of high-temperature inactivation.

[0026] 4. The epoxy-mPHBV-sodium alginate-polyethylene glycol crosslinking system wall material used in this invention can achieve stable controlled release of Artemisia argyi active ingredients. Under normal temperature storage conditions, the leakage of essential oil is low, and the effective ingredients can be released smoothly when worn and used, with good controlled release effect. It solves the problems of easy leakage and uncontrollable functional release of existing microcapsules during storage; and can reduce the loss of active ingredients in the core material during processing.

[0027] 5. The synthetic leather prepared by this invention has been tested and verified to have stable and reliable functional effects. The test data for each performance are as follows: In terms of antibacterial performance, the initial antibacterial rate of the synthetic leather is 99.6-99.9% against Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae, and 98.6-99.2% against Candida albicans. After heat aging at 70℃ and 95% relative humidity for 168 hours, the antibacterial rate is 94.0-97.3%. In terms of anti-mildew performance, the initial anti-mildew level is 0, and it becomes 1 after heat aging. In terms of mugwort fragrance, the initial level reaches 3, and it becomes 2 after heat aging. In terms of deodorization performance, the initial reduction rate of ammonia and acetic acid is 89.8-94.2%, and it becomes 84.0-89.5% after heat aging. Detailed Implementation

[0028] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention are now described.

[0029] Example 1 Preparation of composite microcapsules containing Artemisia argyi active ingredients and antibacterial materials S1. Preparation of Artemisia argyi composite core material β-cyclodextrin-chitosan graft material was dispersed in water, and Artemisia argyi essential oil was added dropwise. After stirring evenly, it was ultrasonically treated at a frequency of 20kHz for 16min. Then Artemisia argyi extract was added, the stirring speed was adjusted to 250rpm, and it was stirred at a constant temperature of 30℃ for 70min. Finally, it was vacuum dried at 40℃ to obtain Artemisia argyi composite core material. The mass ratio of the β-cyclodextrin-chitosan graft, Artemisia argyi essential oil, Artemisia argyi extract, and water is 1:0.15:1.2:15; The Artemisia argyi extract was prepared by water extraction and alcohol precipitation, with a particle size of 5 μm, a total flavonoid content of 8.2%, and a polysaccharide content of 15.4%.

[0030] The preparation method of the β-cyclodextrin-chitosan graft is as follows: β-cyclodextrin is dissolved in a mixed solvent of dimethyl sulfoxide and isopropanol. Epichlorohydrin is added dropwise under stirring. After the addition is complete, the pH of the solution is adjusted to 7 with sodium hydroxide solution. The mixture is stirred at room temperature for 4 hours. Then, chitosan is added to the flask, and the stirring speed is maintained at 250 rpm. The mixture is stirred at room temperature for 5 hours until a homogeneous viscous solution is formed. After the reaction is complete, the reaction solution is filtered. The filter cake is washed with a large amount of deionized water until the pH reaches 6.8. It is then dried in a vacuum drying oven at 48°C for 8.5 hours. After pulverization, it is passed through an 80-mesh sieve to obtain a white powdery β-cyclodextrin-chitosan graft. The mass ratio of dimethyl sulfoxide to isopropanol in the mixed solvent is 1:0.8; The mass ratio of β-cyclodextrin, chitosan, epichlorohydrin, and the mixed solvent is 1:0.8:1.2:2.2.

[0031] Verification of the composite effect of Artemisia argyi core material: Take 10g of core material solution, put it into a centrifuge tube, centrifuge at 8000rpm for 10min. No precipitation or stratification was observed, indicating that the composite material is stable. The inclusion rate of Artemisia argyi active molecules was confirmed to be ≥95% by UV-Vis spectrophotometry.

[0032] S2. Preparation of wall material precursors Epoxy-mPHBV was added to an ethanol / water mixed solvent and stirred at 58°C until completely dissolved. While keeping the temperature constant, sodium alginate oxide and PEG-4000 were added in sequence and stirred until completely dissolved. Citric acid was then added and stirred at 58°C for 35 minutes to activate the solution, resulting in a uniform and transparent wall material precursor solution. The epoxy-mPHBV is a random copolymer of 3-hydroxybutyric acid and 3-hydroxyvalerate, wherein the molar percentage of 3-hydroxyvalerate units is 12 mol%, the epoxy value is 0.08 eq / 100g, and the number average molecular weight is 8000 g / mol. The oxidized sodium alginate is sodium alginate oxidized with sodium periodate, and the aldehyde content of the oxidized sodium alginate is 0.35 mmol / g; The mass ratio of ethanol to water in the ethanol / water mixed solvent is 2.5:7; The mass ratio of epoxy-mPHBV, oxidized sodium alginate, PEG-4000, citric acid, and ethanol / water mixed solvent is 10:3.5:1.8:0.12:120.

[0033] S3, Microencapsulation Water and SMA emulsifier were mixed and stirred to dissolve. The wall material precursor solution was added and mixed evenly. The temperature was maintained at 58℃. Then, Artemisia argyi composite core material, limonene, zeolite and chitosan quaternary ammonium salt were added. The mixture was homogenized at 7500 rpm for 11 min. After homogenization, the reaction system was heated to 73℃ and epichlorohydrin was slowly added dropwise. After the addition was completed, the mixture was stirred at 300 rpm for 2.7 h. After the reaction was completed, the pH was adjusted to 7.2. The mixture was cooled, filtered, washed three times with water, and finally dried under vacuum at 55℃ to obtain composite microcapsules. The particle size of the zeolite is 4 μm; The chitosan quaternary ammonium salt is 2-hydroxypropyltrimethylammonium chloride chitosan with a degree of substitution of 60% and a molecular weight of 40,000 Da. The mass ratio of water, SMA emulsifier, wall material precursor solution, Artemisia argyi composite core material, limonene, zeolite, chitosan quaternary ammonium salt and epichlorohydrin is 100:1:95:22:3.5:7:1:0.05.

[0034] The obtained composite microcapsules were subjected to thermogravimetric analysis in an N2 atmosphere, with a heating rate of 10℃ / min and a test range of 30℃-600℃. The 5% thermogravimetric temperature was found to be 238℃.

[0035] Example 2 Preparation of composite microcapsules containing Artemisia argyi active ingredients and antibacterial materials S1. Preparation of Artemisia argyi composite core material β-cyclodextrin-chitosan graft material was dispersed in water, and Artemisia argyi essential oil was added dropwise. After stirring evenly, it was ultrasonically treated at 25kHz frequency for 14min. Then Artemisia argyi extract was added, the stirring speed was adjusted to 300rpm, and it was stirred at 32℃ for 60min. Finally, it was vacuum dried at 45℃ to obtain Artemisia argyi composite core material. The mass ratio of the β-cyclodextrin-chitosan graft, Artemisia argyi essential oil, Artemisia argyi extract, and water is 1:0.17:1.4:18. The Artemisia argyi extract was prepared by water extraction and alcohol precipitation, with a particle size of 8 μm, a total flavonoid content of 9.2%, and a polysaccharide content of 15.8%.

[0036] The preparation method of β-cyclodextrin-chitosan graft is as follows: β-cyclodextrin is dissolved in a mixed solvent composed of dimethyl sulfoxide and isopropanol, and epichlorohydrin is added dropwise under stirring. After the addition is complete, the pH of the solution is adjusted to 7.5 with sodium hydroxide solution. The mixture is stirred at room temperature for 4.5 hours. Then, chitosan is added to the flask, and the stirring speed is maintained at 300 rpm. The mixture is stirred at room temperature for 4.5 hours until a uniform viscous solution is formed. After the reaction is completed, the reaction solution is filtered, and the filter cake is washed with a large amount of deionized water until the pH is 7.0. The filter cake is then dried in a vacuum drying oven at 50°C for 8 hours. After pulverizing, the product is passed through an 80-mesh sieve to obtain a white powdery β-cyclodextrin-chitosan graft. The mass ratio of dimethyl sulfoxide to isopropanol in the mixed solvent is 1:1; The mass ratio of β-cyclodextrin, chitosan, epichlorohydrin, and the mixed solvent is 1:1:1.3:2.4.

[0037] S2. Preparation of wall material precursors Epoxy-mPHBV was added to an ethanol / water mixed solvent and stirred at 60°C until completely dissolved. While keeping the temperature constant, sodium alginate oxide and PEG-4000 were added in sequence and stirred until completely dissolved. Citric acid was then added and stirred at 60°C for 30 minutes to activate the solution, resulting in a uniform and transparent wall material precursor solution. The epoxy-mPHBV is a random copolymer of 3-hydroxybutyric acid and 3-hydroxyvalerate, wherein the molar percentage of 3-hydroxyvalerate units is 16 mol%, the epoxy value is 0.10 eq / 100g, and the number average molecular weight is 10000 g / mol. The oxidized sodium alginate is sodium alginate oxidized with sodium periodate, and the aldehyde content of the oxidized sodium alginate is 0.40 mmol / g; The mass ratio of ethanol to water in the ethanol / water mixed solvent is 2.8:7; The mass ratio of epoxy-mPHBV, oxidized sodium alginate, PEG-4000, citric acid, and ethanol / water mixed solvent is 10:4:2:0.13:125.

[0038] S3, Microencapsulation Water and SMA emulsifier were mixed and stirred to dissolve. The wall material precursor solution was added and mixed evenly. The temperature was maintained at 60℃. Then, Artemisia argyi composite core material, limonene, zeolite and chitosan quaternary ammonium salt were added. The mixture was homogenized at 8000 rpm for 10 min. After homogenization, the reaction system was heated to 75℃ and epichlorohydrin was slowly added dropwise. After the addition was completed, the mixture was stirred at 350 rpm for 2.5 h. After the reaction was completed, the pH was adjusted to 7, cooled, filtered, washed with water 3 times, and finally vacuum dried at 60℃ to obtain composite microcapsules. The particle size of the zeolite is 5 μm; The chitosan quaternary ammonium salt is 2-hydroxypropyltrimethylammonium chloride chitosan with a degree of substitution of 70% and a molecular weight of 60,000 Da. The mass ratio of water, SMA emulsifier, precursor solution, Artemisia argyi composite core material, limonene, zeolite, chitosan quaternary ammonium salt and epichlorohydrin is 100:1.2:100:25:4:8:1.5:0.06.

[0039] The obtained composite microcapsules were subjected to thermogravimetric analysis in an N2 atmosphere, with a heating rate of 10℃ / min and a test range of 30℃-600℃. The 5% thermogravimetric temperature was found to be 242℃.

[0040] Example 3 Preparation of composite microcapsules containing Artemisia argyi active ingredients and antibacterial materials S1. Preparation of Artemisia argyi composite core material β-cyclodextrin-chitosan graft material was dispersed in water, and Artemisia argyi essential oil was added dropwise. After stirring evenly, it was ultrasonically treated at 30kHz frequency for 12min. Then Artemisia argyi extract was added, the stirring speed was adjusted to 350rpm, and it was stirred at 35℃ for 50min. Finally, it was vacuum dried at 50℃ to obtain Artemisia argyi composite core material. The mass ratio of the β-cyclodextrin-chitosan graft, Artemisia argyi essential oil, Artemisia argyi extract, and water is 1:0.2:1.6:20. The Artemisia argyi extract was prepared by water extraction and alcohol precipitation, with a particle size of 10 μm, a total flavonoid content of 8.7%, and a polysaccharide content of 16.1%.

[0041] The preparation method of the β-cyclodextrin-chitosan graft is as follows: β-cyclodextrin is dissolved in a mixed solvent of dimethyl sulfoxide and isopropanol. Epichlorohydrin is added dropwise under stirring. After the addition is complete, the pH of the solution is adjusted to 8 with sodium hydroxide solution. The mixture is stirred at room temperature for 5 hours. Then, chitosan is added to the flask, and the stirring speed is maintained at 350 rpm. The mixture is stirred at room temperature for 4 hours until a homogeneous viscous solution is formed. After the reaction is complete, the reaction solution is filtered. The filter cake is washed with a large amount of deionized water until the pH reaches 7.2. It is then dried in a vacuum drying oven at 52°C for 7.5 hours. After pulverizing, it is passed through a 100-mesh sieve to obtain a white powdery β-cyclodextrin-chitosan graft. The mass ratio of dimethyl sulfoxide to isopropanol in the mixed solvent is 1:1.2; The mass ratio of β-cyclodextrin, chitosan, epichlorohydrin, and the mixed solvent is 1:1.2:1.5:2.6.

[0042] S2. Preparation of wall material precursors Epoxy-mPHBV was added to an ethanol / water mixed solvent and stirred at 62°C until completely dissolved. While keeping the temperature constant, sodium alginate oxide and PEG-4000 were added in sequence and stirred until completely dissolved. Citric acid was then added and stirred at 62°C for 25 minutes to activate the solution and obtain a uniform and transparent wall material precursor solution. The epoxy-mPHBV is a random copolymer of 3-hydroxybutyric acid and 3-hydroxyvalerate, wherein the molar percentage of 3-hydroxyvalerate units is 18 mol%, the epoxy value is 0.12 eq / 100g, and the number average molecular weight is 12000 g / mol. The oxidized sodium alginate is sodium alginate oxidized with sodium periodate, and the aldehyde content of the oxidized sodium alginate is 0.45 mmol / g; The mass ratio of ethanol to water in the ethanol / water mixed solvent is 3:7; The mass ratio of epoxy-mPHBV, oxidized sodium alginate, PEG-4000, citric acid, and ethanol / water mixed solvent is 10:4.5:2.2:0.15:130.

[0043] S3, Microencapsulation Water and SMA emulsifier were mixed and stirred to dissolve. The wall material precursor solution was added and mixed evenly. The temperature was maintained at 62℃. Then, Artemisia argyi composite core material, limonene, zeolite and chitosan quaternary ammonium salt were added. The mixture was homogenized at 8500 rpm for 9 min. After homogenization, the reaction system was heated to 78℃ and epichlorohydrin was slowly added dropwise. After the addition was completed, the mixture was stirred at 400 rpm for 2.3 h. After the reaction was completed, the pH was adjusted to 6.8, cooled, filtered, washed with water 4 times, and finally dried under vacuum at 65℃ to obtain composite microcapsules. The particle size of the zeolite is 6 μm; The chitosan quaternary ammonium salt is 2-hydroxypropyltrimethylammonium chloride chitosan with a degree of substitution of 80% and a molecular weight of 80,000 Da. The mass ratio of water, SMA emulsifier, precursor solution, Artemisia argyi composite core material, limonene, zeolite, chitosan quaternary ammonium salt and epichlorohydrin is 100:1.5:105:28:4.5:10:2:0.07.

[0044] The obtained composite microcapsules were subjected to thermogravimetric analysis in an N2 atmosphere, with a heating rate of 10℃ / min and a test range of 30℃-600℃. The 5% thermogravimetric temperature was found to be 235℃.

[0045] Example 4 This embodiment is based on Example 2, but omits the preparation steps of the Artemisia argyi composite core material and the β-cyclodextrin-chitosan graft. In the S3 microcapsule forming step, Artemisia argyi essential oil and Artemisia argyi extract of the same dosage and proportion as those used in the preparation of the Artemisia argyi composite core material are used instead of the Artemisia argyi composite core material. All other parts are the same.

[0046] The obtained composite microcapsules were subjected to thermogravimetric analysis in an N2 atmosphere, with a heating rate of 10℃ / min and a test range of 30℃-600℃. The 5% thermogravimetric temperature was found to be 236℃.

[0047] Example 5 Based on Example 2, in the preparation steps of the Artemisia argyi composite core material, the β-cyclodextrin-chitosan graft material is replaced with an equal mass of single β-cyclodextrin, while the rest are the same.

[0048] The obtained composite microcapsules were subjected to thermogravimetric analysis in an N2 atmosphere, with a heating rate of 10℃ / min and a test range of 30℃-600℃. The 5% thermogravimetric temperature was found to be 238℃.

[0049] Example 6 Based on Example 2, this embodiment omits the preparation step of the wall material precursor. In the microcapsule molding step, waterborne polyurethane prepolymer is used as the microcapsule wall material, and the rest are the same.

[0050] The microcapsule forming method is as follows: Water and SMA emulsifier were mixed and stirred to dissolve. Waterborne polyurethane prepolymer was added and mixed evenly. The temperature was maintained at 60℃. Then, Artemisia argyi composite core material, limonene, zeolite and chitosan quaternary ammonium salt were added. The mixture was homogenized at 8000 rpm for 10 min. After homogenization, the reaction system was heated to 75℃ and reacted at 350 rpm for 2.5 h. After the reaction was completed, the pH was adjusted to 6.8-7.2. The mixture was cooled, filtered, washed with water 3-4 times, and finally vacuum dried at 55-65℃ to obtain composite microcapsules. The particle size of the zeolite is 5 μm; The chitosan quaternary ammonium salt is 2-hydroxypropyltrimethylammonium chloride chitosan with a degree of substitution of 70% and a molecular weight of 60,000 Da. The mass ratio of water, SMA emulsifier, precursor solution, Artemisia argyi composite core material, limonene, zeolite and chitosan quaternary ammonium salt is 100:1.2:100:25:4:8:1.5.

[0051] The obtained composite microcapsules were subjected to thermogravimetric analysis in an N2 atmosphere, with a heating rate of 10℃ / min and a test range of 30℃-600℃. The 5% thermogravimetric temperature was found to be 192℃.

[0052] Example 7 Preparation of a synthetic leather for footwear that provides a long-lasting release of artemisia scent and antibacterial properties: (1) Substrate pretreatment With a weight of 200 g / m 2 The nonwoven fabric is immersed in water at 45℃ for 5.5 minutes and then dried at 75℃ for 3.5 minutes to obtain the pretreated nonwoven fabric.

[0053] (2) Preparation of wet slurry Add 5.5 wt% of the composite microcapsules prepared in Example 1 and 0.6 wt% of KH-550 to polyurethane resin and disperse at 1000 rpm for 35 min to obtain a wet slurry. The polyurethane resin has a solid content of 28 wt% and the solvent is N,N-dimethylformamide.

[0054] (3) Scraping and solidification The wet slurry was coated onto the pretreated nonwoven fabric to a thickness of 0.33 mm, and then immersed in a coagulation bath at 23°C for 16 min to form a porous wet base layer rich in microcapsules. The coagulation bath is an 18wt% N,N-dimethylformamide solution.

[0055] (4) Washing and drying Wash thoroughly with running water to remove N,N-dimethylformamide, and then dry at 95°C for 5 minutes.

[0056] (5) Formulation of functional coating layer Take the water-based coating agent, add 3.8 wt% of the composite microcapsules prepared in Example 1 and 0.4 wt% of KH-550, and stir at 350 rpm for 25 min.

[0057] (6) Coating and drying The coating agent was applied to the base surface using a roller coating method, with a liquid load of 75 g / m². 2 Then dry at 105℃ for 2.2 min.

[0058] (7) Low-temperature embossing Using an embossing machine, emboss for 28 seconds at 120℃ and 2.2MPa pressure.

[0059] (8) Post-processing After being hung and cured at room temperature for 22 hours, the product is inspected and cut to obtain the finished synthetic leather for footwear.

[0060] Example 8 Preparation of a synthetic leather for footwear that provides a long-lasting release of artemisia scent and antibacterial properties: (1) Substrate pretreatment With a weight of 220 g / m 2 The nonwoven fabric is immersed in water at 50°C for 5 minutes and then dried at 80°C for 3 minutes to obtain the pretreated nonwoven fabric.

[0061] (2) Preparation of wet slurry Add 6 wt% of the composite microcapsules prepared in Example 2 and 0.7 wt% of KH-550 to polyurethane resin and disperse at 1100 rpm for 30 min to obtain a wet slurry. The polyurethane resin has a solid content of 30 wt% and the solvent is N,N-dimethylformamide.

[0062] (3) Scraping and solidification The wet slurry was coated onto the pretreated nonwoven fabric to a thickness of 0.35 mm, and then immersed in a coagulation bath at 25°C for 15 min to form a porous wet base layer rich in microcapsules. The coagulation bath is a 20wt% N,N-dimethylformamide solution.

[0063] (4) Washing and drying Wash thoroughly with running water to remove N,N-dimethylformamide, and then dry at 100°C for 4.5 min.

[0064] (5) Formulation of functional coating layer Take the water-based coating agent, add 4 wt% of the composite microcapsules prepared in Example 2 and 0.5 wt% of KH-550, and stir at 400 rpm for 20 min.

[0065] (6) Coating and drying The coating agent was applied to the base surface using a roller coating method, with a liquid load of 80 g / m². 2 Then dry at 110℃ for 2 minutes.

[0066] (7) Low-temperature embossing Using an embossing machine, emboss for 30 seconds at 125℃ and 2MPa pressure.

[0067] (8) Post-processing After being hung and cured at room temperature for 24 hours, the product is inspected and cut to obtain the finished synthetic leather for footwear.

[0068] Example 9 Preparation of a synthetic leather for footwear that provides a long-lasting release of artemisia scent and antibacterial properties: (1) Substrate pretreatment With a weight of 240 g / m 2 The nonwoven fabric is immersed in water at 55℃ for 4.5 minutes and then dried at 85℃ for 2.5 minutes to obtain the pretreated nonwoven fabric.

[0069] (2) Preparation of wet slurry Add 6.5 wt% of the composite microcapsules prepared in Example 3 and 0.8 wt% of KH-550 to polyurethane resin and disperse at 1200 rpm for 25 min to obtain a wet slurry. The polyurethane resin has a solid content of 32 wt% and the solvent is N,N-dimethylformamide.

[0070] (3) Scraping and solidification The wet slurry was coated onto the pretreated nonwoven fabric to a thickness of 0.37 mm, and then immersed in a coagulation bath at 27°C for 14 min to form a porous wet base layer rich in microcapsules. The coagulation bath is a 22wt% N,N-dimethylformamide solution.

[0071] (4) Washing and drying Wash thoroughly with running water to remove N,N-dimethylformamide, and then dry at 105°C for 4 minutes.

[0072] (5) Formulation of functional coating layer Take the water-based coating agent, add 4.2 wt% of the composite microcapsules prepared in Example 3 and 0.6 wt% of KH-550, and stir at 450 rpm for 15 min.

[0073] (6) Coating and drying The coating agent was applied to the base surface using a roller coating method, with a liquid concentration of 85 g / m². 2 Then dry at 115℃ for 1.8 min.

[0074] (7) Low-temperature embossing Using an embossing machine, emboss for 32 seconds at 130℃ and 1.8MPa pressure.

[0075] (8) Post-processing After being hung and cured at room temperature for 26 hours, the product is inspected and cut to obtain the finished synthetic leather for footwear.

[0076] Example 10 Preparation of a synthetic leather for footwear that provides a long-lasting release of artemisia scent and antibacterial properties: (1) Substrate pretreatment With a weight of 220 g / m 2 The nonwoven fabric is immersed in water at 50°C for 5 minutes and then dried at 80°C for 3 minutes to obtain the pretreated nonwoven fabric.

[0077] (2) Preparation of wet slurry Add 6 wt% of the composite microcapsules prepared in Example 4 and 0.7 wt% of KH-550 to polyurethane resin and disperse at 1100 rpm for 30 min to obtain a wet slurry. The polyurethane resin has a solid content of 30 wt% and the solvent is N,N-dimethylformamide.

[0078] (3) Scraping and solidification The wet slurry was coated onto the pretreated nonwoven fabric to a thickness of 0.35 mm, and then immersed in a coagulation bath at 25°C for 15 min to form a porous wet base layer rich in microcapsules. The coagulation bath is a 20wt% N,N-dimethylformamide solution.

[0079] (4) Washing and drying Wash thoroughly with running water to remove N,N-dimethylformamide, and then dry at 100°C for 4.5 min.

[0080] (5) Formulation of functional coating layer Take the water-based coating agent, add 4 wt% of the composite microcapsules prepared in Example 4 and 0.5 wt% of KH-550, and stir at 400 rpm for 20 min.

[0081] (6) Coating and drying The coating agent was applied to the base surface using a roller coating method, with a liquid load of 80 g / m². 2 Then dry at 110℃ for 2 minutes.

[0082] (7) Low-temperature embossing Using an embossing machine, emboss for 30 seconds at 125℃ and 2MPa pressure.

[0083] (8) Post-processing After being hung and cured at room temperature for 24 hours, the product is inspected and cut to obtain the finished synthetic leather for footwear.

[0084] Example 11 Preparation of a synthetic leather for footwear that provides a long-lasting release of artemisia scent and antibacterial properties: (1) Substrate pretreatment With a weight of 220 g / m 2 The nonwoven fabric is immersed in water at 50°C for 5 minutes and then dried at 80°C for 3 minutes to obtain the pretreated nonwoven fabric.

[0085] (2) Preparation of wet slurry Add 6 wt% of the composite microcapsules prepared in Example 5 and 0.7 wt% of KH-550 to polyurethane resin and disperse at 1100 rpm for 30 min to obtain a wet slurry. The polyurethane resin has a solid content of 30 wt% and the solvent is N,N-dimethylformamide.

[0086] (3) Scraping and solidification The wet slurry was coated onto the pretreated nonwoven fabric to a thickness of 0.35 mm, and then immersed in a coagulation bath at 25°C for 15 min to form a porous wet base layer rich in microcapsules. The coagulation bath is a 20wt% N,N-dimethylformamide solution.

[0087] (4) Washing and drying Wash thoroughly with running water to remove N,N-dimethylformamide, and then dry at 100°C for 4.5 min.

[0088] (5) Formulation of functional coating layer Take the water-based coating agent, add 4 wt% of the composite microcapsules prepared in Example 5 and 0.5 wt% of KH-550, and stir at 400 rpm for 20 min.

[0089] (6) Coating and drying The coating agent was applied to the base surface using a roller coating method, with a liquid load of 80 g / m². 2 Then dry at 110℃ for 2 minutes.

[0090] (7) Low-temperature embossing Using an embossing machine, emboss for 30 seconds at 125℃ and 2MPa pressure.

[0091] (8) Post-processing After being hung and cured at room temperature for 24 hours, the product is inspected and cut to obtain the finished synthetic leather for footwear.

[0092] Example 12 Preparation of a synthetic leather for footwear that provides a long-lasting release of artemisia scent and antibacterial properties: (1) Substrate pretreatment With a weight of 220 g / m 2 The nonwoven fabric is immersed in water at 50°C for 5 minutes and then dried at 80°C for 3 minutes to obtain the pretreated nonwoven fabric.

[0093] (2) Preparation of wet slurry Add 6 wt% of the composite microcapsules prepared in Example 6 and 0.7 wt% of KH-550 to polyurethane resin and disperse at 1100 rpm for 30 min to obtain a wet slurry. The polyurethane resin has a solid content of 30 wt% and the solvent is N,N-dimethylformamide.

[0094] (3) Scraping and solidification The wet slurry was coated onto the pretreated nonwoven fabric to a thickness of 0.35 mm, and then immersed in a coagulation bath at 25°C for 15 min to form a porous wet base layer rich in microcapsules. The coagulation bath is a 20wt% N,N-dimethylformamide solution.

[0095] (4) Washing and drying Wash thoroughly with running water to remove N,N-dimethylformamide, and then dry at 100°C for 4.5 min.

[0096] (5) Formulation of functional coating layer Take the water-based coating agent, add 4 wt% of the composite microcapsules prepared in Example 6 and 0.5 wt% of KH-550, and stir at 400 rpm for 20 min.

[0097] (6) Coating and drying The coating agent was applied to the base surface using a roller coating method, with a liquid load of 80 g / m². 2 Then dry at 110℃ for 2 minutes.

[0098] (7) Low-temperature embossing Using an embossing machine, emboss for 30 seconds at 125℃ and 2MPa pressure.

[0099] (8) Post-processing After being hung and cured at room temperature for 24 hours, the product is inspected and cut to obtain the finished synthetic leather for footwear.

[0100] Experimental Example 1 For the synthetic leather prepared in Examples 7-12, the initial antibacterial and antifungal properties of the synthetic leather were tested using the test methods of standard QB / T 4341—2012 "Antibacterial Polyurethane Synthetic Leather—Test Methods and Antibacterial Effects" and GB / T 20944.3-2008 "Evaluation of Antibacterial Properties of Textiles Part 3: Vibration Method". Specifically, the detection of Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and the antifungal grade were based on standard QB / T 4341—2012, while the detection of Candida albicans was based on standard GB / T 20944.3-2008. The test results are shown in Table 1.

[0101] Table 1 Initial antibacterial and antifungal properties of synthetic leather In the initial state, Examples 7-9, which used complete β-cyclodextrin-chitosan grafts, showed antibacterial rates of over 99.6% against Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae, and over 99.0% against Candida albicans, with a mildew resistance level of 0, demonstrating the best performance. The antibacterial rates and mildew resistance levels of Example 10, which omitted the core material locking mechanism, Example 11, which used a single β-cyclodextrin as a substitute, and Example 12, which used waterborne polyurethane, showed almost no decrease.

[0102] Experimental Example 2 The synthetic leathers prepared in Examples 7-12 were aged in hot air at 70°C and 95% relative humidity for 168 hours, and their antibacterial and antifungal properties were then tested. The test results are shown in Table 2.

[0103] Table 2 Antibacterial and antifungal properties after heat aging After heat aging, the antibacterial rate of Examples 7-9 remained above 95.8%, and the anti-mildew grade was 1, demonstrating outstanding performance stability. The antibacterial rate of Example 10 decreased to 90.9%-92.6%, and the anti-mildew grade decreased to 2. The effect of Example 11 was between the two, indicating that the dual structure of core material locking and wall material protection can effectively resist the impact of high temperature and high humidity on function. The antibacterial rate of the polyurethane wall material in Example 12 decreased to about 80%, and the anti-mildew grade decreased to 3, directly proving that the heat resistance and the protective effect on the core material of the composite wall material of the present invention are far superior to those of waterborne polyurethane wall material.

[0104] Experimental Example 3 The aroma of artemisia was detected by olfactory identification of the synthetic leather prepared in Examples 7-12, and the aroma level of artemisia was also detected after aging in hot air at 70°C and 95% relative humidity for 168 hours. The test results are shown in Table 3.

[0105] Table 3. Aroma Grades of Artemisia after Heat Aging All examples initially exhibited a mugwort aroma level of 3, indicating a rich and consistent fragrance. After heat aging, the aroma of Examples 7-9 remained at level 2, showing minimal decay and retaining a clear mugwort aroma. Examples 10-11 decreased to level 1, demonstrating that the β-cyclodextrin-chitosan graft can effectively lock in mugwort essential oil and reduce aroma volatilization during heat aging. Example 12 decreased to level 0, indicating that the wall material of this invention can effectively prevent the volatilization and loss of mugwort essential oil during high-temperature processing and storage.

[0106] Test Example 4 For the synthetic leather prepared in Examples 7-12, the deodorization (ammonia and acetic acid) performance was tested. The deodorization rate was tested according to GB / T 39932-2019. In an experimental environment with a temperature of 23℃±1℃ and a relative humidity of 50%±5%, the initial deodorization rate of the samples for ammonia and acetic acid gases with an initial concentration of (50±5) ppm was measured after 24 hours of sealing. Subsequently, the same batch of samples were placed in a hot air aging chamber at 70℃ and 95% relative humidity for 168 hours to simulate accelerated aging, and their deodorization rate was measured again. The results are shown in Table 4.

[0107] Table 4. Deodorization rates for ammonia and acetic acid In the initial state, Examples 7-9, using β-cyclodextrin-chitosan grafted material as the core material locking structure and epoxy-mPHBV-sodium alginate-polyethylene glycol crosslinking system as the wall material, achieved the best deodorization effect due to the synergistic effect of Artemisia argyi, zeolite, and chitosan quaternary ammonium salt, with ammonia and acetic acid reduction rates exceeding 89.5%. Example 11, using a single β-cyclodextrin instead of the composite grafted material, had a limited locking effect and a slightly lower deodorization rate. Example 10, omitting the core material locking step, resulted in easy loss of functional components and the lowest deodorization rate.

[0108] After thermal aging, the deodorization rate of Examples 7-9 remained above 84.0%, with a small decrease, while that of Example 10 decreased to 60.7-65.2%, which fully demonstrates that the locking system can effectively improve the thermal stability of deodorization performance and meet the odor control requirements of long-term closed-loop wear of footwear; the deodorization rate of Example 12 decreased to about 50%, further verifying the long-term protective effect of the wall material of the present invention on functional components.

[0109] Experimental Example 5 For the synthetic leathers prepared in Examples 8 and 12, a simulated shoe environment was established, with a storage group at 25°C room temperature + 30% relative humidity and a simulated wearing group at 35°C foot temperature + 90% relative humidity. Samples were taken at 1, 7, 30, 60, and 90 days to detect the remaining content of eucalyptol, a characteristic marker of Artemisia argyi essential oil, in the samples. The cumulative release rate of Artemisia argyi essential oil at different time points was calculated based on the total eucalyptol content in the initial samples. The results are shown in Table 5. Table 5. Cumulative release rate of Artemisia argyi essential oil under different conditions The results of this experiment show that the synthetic leather of Example 8 of the present invention, under simulated ambient temperature storage conditions, has a cumulative release rate of only 15.7% of Artemisia argyi essential oil over 90 days, achieving efficient preservation of active ingredients during storage and effectively preventing premature loss of aroma and functional degradation during the product's shelf life. Under simulated wearing conditions of 35°C foot temperature and high humidity, Artemisia argyi essential oil can achieve stable and continuous release, with a cumulative release rate of 80.4% over 90 days, without the problems of initial explosive release or no effective release in the later stages, fully meeting the functional requirements of long-term wear of footwear products. In contrast, the conventional polyurethane wall material synthetic leather of Example 12, lacking precise controlled release design, has a cumulative release rate of 57.8% of essential oil over 90 days under ambient temperature storage conditions, with more than half of the effective active ingredients lost during storage. Under simulated wearing conditions, it exhibits severe initial explosive release, with a cumulative release rate of 73.2% after 30 days, and no effective functional release in the later stages, completely failing to meet the long-term use requirements of footwear products. The epoxy-mPHBV-sodium alginate-polyethylene glycol composite wall material of the present invention has a good controlled release effect.

[0110] Unless otherwise specified, all percentages mentioned in this application are percentages by mass.

[0111] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A synthetic leather for footwear that provides a long-lasting release of mugwort scent and antibacterial properties, characterized in that, It includes a pre-treated nonwoven fabric, a wet-laid base layer, and a functional coating layer; the wet-laid base layer is coated on the surface of the pre-treated nonwoven fabric, and the functional coating layer is coated on the surface of the wet-laid base layer; both the wet-laid base layer and the functional coating layer contain composite microcapsules. The composite microcapsule has a core-wall structure. The composite microcapsule has a core composed of a combination of Artemisia argyi composite core material, limonene, zeolite and chitosan quaternary ammonium salt, and a wall material composed of an epoxy-mPHBV-sodium alginate-polyethylene glycol crosslinking system. The preparation method of the Artemisia argyi composite core material is as follows: disperse β-cyclodextrin-chitosan graft in water, add Artemisia argyi essential oil, stir evenly and then sonicate for 12-16 min, then add Artemisia argyi extract, adjust the stirring speed to 250-350 rpm, stir at a constant temperature of 30-35℃ for 50-70 min, and then vacuum dry at 40-50℃ to obtain the Artemisia argyi composite core material.

2. The synthetic leather for footwear with a long-lasting release of mugwort scent and antibacterial function according to claim 1, characterized in that, The frequency of the ultrasonic treatment is 20-30kHz; The mass ratio of the β-cyclodextrin-chitosan graft, Artemisia argyi essential oil, Artemisia argyi extract, and water is 1:0.15-0.2:1.2-1.6:15-20; The Artemisia argyi extract has a particle size of 5-10 μm and a total flavonoid content of not less than 8.0% and a polysaccharide content of not less than 15.0%.

3. The synthetic leather for footwear with a long-lasting release of mugwort scent and antibacterial function according to claim 1, characterized in that, The preparation method of the β-cyclodextrin-chitosan graft is as follows: β-cyclodextrin is dissolved in a mixed solvent composed of dimethyl sulfoxide and isopropanol. Epichlorohydrin is added dropwise under stirring. After the addition is complete, the pH of the solution is adjusted to 7-8. The mixture is stirred at room temperature for 4-5 hours. Chitosan is then added to the flask. The stirring speed is maintained at 250-350 rpm. The mixture is stirred at room temperature for 4-5 hours until a uniform viscous solution is formed. After the reaction is complete, the reaction solution is filtered. The filter cake is washed with water until the pH is 6.8-7.

2. It is then dried in a vacuum drying oven at 48-52℃ for 7.5-8.5 hours. After pulverizing, the product is passed through an 80-100 mesh sieve to obtain a white powdery β-cyclodextrin-chitosan graft.

4. The synthetic leather for footwear with a long-lasting release of mugwort scent and antibacterial function according to claim 3, characterized in that, The mass ratio of dimethyl sulfoxide to isopropanol in the mixed solvent is 1:0.8-1.2; The mass ratio of β-cyclodextrin, chitosan, epichlorohydrin and the mixed solvent is 1:0.8-1.2:1.2-1.5:2.2-2.

6.

5. The synthetic leather for footwear with a long-lasting release of mugwort scent and antibacterial function according to claim 1, characterized in that, The preparation process of the composite microcapsules includes the preparation of the wall material precursor and the microcapsule molding. The preparation method of the wall material precursor is as follows: epoxy-mPHBV is added to an ethanol / water mixed solvent and stirred at 58-62℃ until completely dissolved. While keeping the temperature constant, sodium alginate oxide and PEG-4000 are added in sequence and stirred until completely dissolved. Then, citric acid is added and stirred at 58-62℃ for 25-35 minutes to activate the solution and obtain a uniform and transparent wall material precursor solution.

6. The synthetic leather for footwear with a long-lasting release of mugwort scent and antibacterial function according to claim 5, characterized in that, The epoxy-mPHBV is a random copolymer of 3-hydroxybutyric acid and 3-hydroxyvalerate, wherein the molar percentage of 3-hydroxyvalerate units is 12-18 mol%, the epoxy value is 0.08-0.12 eq / 100g, and the number average molecular weight is 8000-12000 g / mol. The oxidized sodium alginate is sodium alginate oxidized with sodium periodate, and the aldehyde content of the oxidized sodium alginate is 0.35-0.45 mmol / g; The mass ratio of ethanol to water in the ethanol / water mixed solvent is 2.5-3:7; The mass ratio of epoxy-mPHBV, oxidized sodium alginate, PEG-4000, citric acid, and ethanol / water mixed solvent is 10:3.5-4.5:1.8-2.2:0.12-0.15:120-130.

7. The synthetic leather for footwear with a long-lasting release of mugwort scent and antibacterial function according to claim 5, characterized in that, The microcapsule forming method is as follows: water and SMA emulsifier are mixed and stirred to dissolve. A wall material precursor solution is added and mixed evenly. The temperature is maintained at 58-62℃. Then, Artemisia argyi composite core material, limonene, zeolite, and chitosan quaternary ammonium salt are added. The mixture is homogenized at 7500-8500 rpm for 9-11 min. After homogenization, the reaction system is heated to 73-78℃, and epichlorohydrin is slowly added dropwise. After the addition is complete, the mixture is stirred at 300-400 rpm for 2.3-2.7 h. After the reaction is completed, the pH is adjusted to 6.8-7.2, cooled, filtered, and washed with water 3-4 times. Finally, the mixture is vacuum dried at 55-65℃ to obtain composite microcapsules.

8. The synthetic leather for footwear with a long-lasting release of mugwort scent and antibacterial function according to claim 7, characterized in that, The particle size of the zeolite is 4-6 μm; The chitosan quaternary ammonium salt is 2-hydroxypropyltrimethylammonium chloride chitosan, with a degree of substitution of 60-80% and a molecular weight of 40,000-80,000 Da; The mass ratio of water, SMA emulsifier, wall material precursor solution, Artemisia argyi composite core material, limonene, zeolite, chitosan quaternary ammonium salt and epichlorohydrin is 100:1-1.5:95-105:22-28:3.5-4.5:7-10:1-2:0.05-0.

07.

9. The synthetic leather for footwear according to any one of claims 1-8, characterized in that, The preparation method includes the following steps: (1) Substrate pretreatment: The nonwoven fabric is immersed in water at 45-55℃ for 4.5-5.5 min, and then dried at 75-85℃ for 2.5-3.5 min to obtain the pretreated nonwoven fabric; (2) Wet slurry preparation: Composite microcapsules and KH-550 are added to polyurethane resin and dispersed at 1000-1200 rpm for 25-35 min to obtain the wet slurry; (3) Coating and coagulation: The wet slurry is coated on the pretreated nonwoven fabric, and then immersed in a coagulation bath at 23-27℃ for 14-16 min to form a porous wet base layer rich in microcapsules; (4) Washing and drying: The nonwoven fabric is thoroughly washed with running water to remove N,N-dimethylformamide, and then dried at 95-105℃. (5) Preparation of functional coating layer: Take water-based coating agent, add composite microcapsules and KH-550, stir at 350-450 rpm for 15-25 min; (6) Coating and drying: Apply coating agent to the base surface by roller coating method, with a liquid amount of 75-85 g / m 2 Then dry at 105-115℃ for 1.8-2.2 min; (7) Low temperature embossing: use an embossing machine to emboss for 28-32 s at 120-130℃ and 1.8-2.2 MPa pressure; (8) Post-treatment: hang and mature at room temperature for 22-26 h, then inspect and cut to obtain finished synthetic leather for shoes.

10. The preparation method according to claim 9, characterized in that, The polyurethane resin has a solid content of 28-32 wt% and the solvent is N,N-dimethylformamide; The mass ratio of polyurethane resin, composite microcapsules, and KH-550 in the wet slurry is 100:5.5-6.5:0.6-0.

8. The mass ratio of water-based coating agent, composite microcapsules and KH-550 in the functional coating layer is 100:3.8-4.2:0.4-0.6.

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