A wear-resistant slow-release microcapsule, a preparation method and application thereof

Abstract

The present application belongs to the technical field of biomedical textile materials, and relates to a wear-resistant slow-release microcapsule, a preparation method and application thereof. The wear-resistant slow-release microcapsule has a core-shell structure, and the shell layer is composed of an inner shell layer and an outer shell layer. The core layer is an antibacterial essential oil, the inner shell layer is an organic material layer with water-swelling properties, and the outer shell layer is a silicon dioxide layer. In the preparation, when the antibacterial essential oil is in the state of emulsion droplets, the organic material with water-swelling properties is wrapped on the surface of the antibacterial essential oil by a complex coagulation method to obtain an intermediate product, and then the silicon dioxide is wrapped on the surface of the intermediate product by a tetraethyl orthosilicate hydrolysis method, so that the wear-resistant slow-release microcapsule is obtained. In the application, the wear-resistant slow-release microcapsule is arranged on the fabric by a padding method to prepare a high-wear-resistant antifungal fabric. The preparation method is simple. The product has a slow-release effect and high friction durability. In the application, the fabric has good antifungal effect.

Description

Technical Field

[0001] This invention belongs to the field of biomedical textile materials technology, and relates to a wear-resistant sustained-release microcapsule, its preparation method and application. Background Technology

[0002] Integrating antibacterial drugs into fabrics via cross-linking or impregnation is a common method for preparing antibacterial fabrics. Military training is often lengthy and intense, leading to increased friction between fabrics. Therefore, military antifungal textiles require higher abrasion resistance than general antifungal textiles. Microencapsulation technology refers to a technique that uses polymers or inorganic materials as wall materials to encapsulate specific substances as a core. Microencapsulation technology can alter the physical properties of the core material, improve its stability, reduce its potential reaction with external factors, and slow down the release rate of the core material.

[0003] Traditional microcapsules are generally made of organic or inorganic wall materials. Organic wall material microcapsules have good sustained-release properties, but they have certain defects in strength and wear resistance, such as acrylic microcapsules (CN103458684A, CN120040139A) and natural polymer wall material microcapsules (CN102824332A, CN104153032A). Inorganic wall materials, although they have good thermal conductivity and high strength, have certain defects in sustained-release properties due to their semi-enclosed nature, such as silica microcapsules (CN119281241A, CN118698454A).

[0004] CN102367632A relates to a natural antibacterial textile containing tangerine peel extract, comprising a base fabric and microcapsules attached to the fibers of the base fabric. The microcapsules are made by emulsion polymerization of tangerine peel extract, polyvinyl alcohol, glutaraldehyde, and an emulsifier. Methods for attaching the microcapsules to the base fabric include impregnation, padding, and printing. The resulting textile exhibits strong antifungal activity, maintaining an inhibition rate of over 80% against *Trichophyton rubrum* and *Microsporum simsii* after 20 washes. It is safe, environmentally friendly, and wash-resistant, and the preparation process is simple, suitable for large-scale industrial production. The shortcomings of this patent are that the antifungal agent is tangerine peel extract, failing to utilize the synergistic effect between antifungal agents. Furthermore, in vitro experiments showed that 25% and 50% concentrations of tangerine peel extract had no inhibitory effect on *Candida albicans*. Additionally, the wall materials of the microcapsules, polyvinyl alcohol and glutaraldehyde, have limited mechanical strength, making it impossible to maintain antifungal activity under prolonged friction on the textile.

[0005] In Reference 1 (Preparation of Bergamot Polyurea Microcapsules and Their Application in Viscose Spunlace Nonwovens [D], 2025.), researchers prepared bergamot polyurea microcapsules using interfacial polymerization for antibacterial purposes in viscose spunlace nonwovens. Using bergamot essential oil as the functional core material, isophorone diisocyanate (IPDI) and monomeric amine (DETA) underwent interfacial polymerization to form the wall material, encapsulating bergamot essential oil to form bergamot polyurea microcapsules. Further, a modification layer was formed by reacting the microcapsule wall material with the natural biological extract polylysine (ε-PL). Finally, the microcapsule was grafted onto an aldehyde-based oxidized viscose spunlace nonwoven material via Schiff base reaction using an impregnation method, resulting in an antibacterial aromatic composite functional material with both sustained-release and reactive-release properties, good mechanical properties, hydrophilicity, and high water and oil absorption rates. In this paper, researchers used a Martindale abrasion tester and applied a 9 kPa load (594 g) to the surface, which is approximately 10.31 N of pressure applied to a surface measuring 6.44 × 10⁻⁶ mm². -4 m 2 The friction area was measured, and 50 rubs were used to simulate the friction effect applied in a real-life usage scenario. The release of the main volatile substances in the sample after friction was significantly increased. At 30℃, the release amount reached 276.24μg, which is 30.72 times that at the same temperature without friction. At 70℃, it reached a maximum of 521.75μg, indicating poor friction durability.

[0006] In Reference 2 (Microencapsulation of multi-component traditional Chinese herbs extracts and its application to traditional Chinese medicines loaded textiles[J]. Colloid Surface B, 2024, 240.), researchers used important extracts containing different active ingredients as the core material of microcapsules, β-cyclodextrin as the wall material, and polyacrylate as a binder to load the microcapsules onto fabrics. Simulating the controlled release of microcapsules under different conditions may provide new potential applications for the material. The results showed that the constructed microcapsules had smooth surfaces without depressions and could continuously release for more than 30 days. The release behavior of the microcapsules followed different release mechanisms and could be modulated by temperature and water molecules. The abrasion resistance test was conducted according to standard ISO 105-X12:2016 (which describes a method for determining the rubbing fastness of textiles). After 50 rubbing cycles under a load of 9±0.2 N, the fabric loaded with microcapsules showed a high essential oil loss rate of 27.5%.

[0007] Therefore, existing sustained-release microcapsules cannot simultaneously possess excellent sustained-release performance and high wear resistance, and cannot achieve stable drug release under prolonged friction. Researching a wear-resistant sustained-release microcapsule, its preparation method, and its application to solve the problems existing in the current technology is of great significance. Summary of the Invention

[0008] The purpose of this invention is to solve the problems existing in the prior art and to provide a wear-resistant sustained-release microcapsule, its preparation method and application.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0010] A wear-resistant sustained-release microcapsule has a core-shell structure, with the shell consisting of an inner shell layer and an outer shell layer; the core layer is an antibacterial essential oil, the inner shell layer is an organic material layer with water-swelling properties, and the outer shell layer is a silica layer.

[0011] In an aqueous environment, the wear-resistant sustained-release microcapsules of this invention exhibit an inner shell that expands upon contact with water, increasing the inter-chain distance within the inner shell and allowing antibacterial essential oils to penetrate it. The outer shell is a silica layer, an amorphous silica network (in microcapsule technology, the silica layer is an amorphous silica network) with nanoscale pores and a network structure, giving it flexibility and deformability, enabling it to withstand certain internal stresses without brittle fracture. Therefore, after the inner shell expands, the outer shell experiences uniform tensile stress, undergoing elastic expansion and slight elastic deformation (i.e., the network structure is slightly "stretched out"), thereby increasing the porosity between molecular chains and providing more channels for the release of antibacterial essential oils. Thus, in an aqueous environment, compared to microcapsules with only an inorganic shell, the wear-resistant sustained-release microcapsules of this invention demonstrate superior drug release capability.

[0012] Because the outer shell of the wear-resistant sustained-release microcapsules of the present invention is a silicon dioxide layer, it is more wear-resistant than the microcapsules of the prior art that only have an organic shell layer.

[0013] Therefore, in an aqueous environment, the wear-resistant sustained-release microcapsules of the present invention possess both excellent sustained-release performance and high wear resistance.

[0014] As a preferred technical solution:

[0015] The wear-resistant sustained-release microcapsule described above contains antibacterial essential oils of Cnidium monnieri essential oil and / or Sophora flavescens essential oil.

[0016] The wear-resistant sustained-release microcapsule described above contains an antibacterial essential oil that is a mixture of Cnidium monnieri essential oil and Sophora flavescens essential oil in a volume ratio of 6:1 to 1:6.

[0017] The wear-resistant sustained-release microcapsule described above has an organic material layer with water-swelling properties formed by a network structure of chitosan (CS), gum arabic (GA), and glutaraldehyde. Chitosan and gum arabic are linked by ionic bonds, while glutaraldehyde and chitosan are linked by covalent bonds. Specifically, in acidic solutions, the -NH2 group in the chitosan molecule combines with hydrogen ions to produce -NH4+. 3+ Glutaraldehyde carries a positive charge; gum arabic molecules have -COOH groups, which are generally negatively charged in aqueous solutions, allowing chitosan and gum arabic to be linked by ionic bonds. The two -CHO groups of glutaraldehyde react with the -NH2 groups of chitosan to form C=N, thus achieving covalent cross-linking. Both chitosan and gum arabic are natural polymers, biodegradable and non-toxic, meeting the safety requirements for textiles. Chitosan is positively charged, while gum arabic is negatively charged. When the human body sweats profusely, the sweat is weakly alkaline, which weakens the positive charge of chitosan, thus reducing the electrostatic interaction between chitosan and gum arabic. This results in a greater expansion of the inner shell, facilitating the diffusion of the core layer. Glutaraldehyde enhances the mechanical properties of the organic layer by forming covalent bonds stronger than ionic bonds. Furthermore, when in contact with weakly alkaline sweat, the ionic bonds are weakened while the covalent bonds ensure that the expansion process only involves swelling, preventing the network structure from disintegrating.

[0018] The wear-resistant sustained-release microcapsule described above has a core layer diameter of 0.93±0.40μm, an inner shell layer thickness of 0.70+0.22μm, and an outer shell layer thickness of 0.53±0.29μm.

[0019] The present invention also provides a method for preparing a wear-resistant sustained-release microcapsule as described in any of the preceding claims. When the antibacterial essential oil is in the form of droplets, an organic material with water-swelling properties is coated on the surface of the antibacterial essential oil by a complex coagulation method to obtain an intermediate product. Then, silica is coated on the surface of the intermediate product by a tetraethyl orthosilicate (TEOS) hydrolysis method to obtain the wear-resistant sustained-release microcapsule.

[0020] As a preferred technical solution:

[0021] The steps for coating the surface of the antibacterial essential oil with an organic material that swells upon contact with water, as described above, are as follows:

[0022] (a) Gum arabic is added to water to prepare an aqueous solution of gum arabic under water bath heating to 30-60°C. Then, while maintaining the water bath heating temperature, antibacterial essential oil and emulsifier are added to the aqueous solution of gum arabic. The mixture is stirred at 5000-15000 rpm for 1-10 min. Then, a glacial acetic acid solution of chitosan is added dropwise at 1-2 mL / min at 5000-15000 rpm to obtain a mixture. The emulsifier is used to uniformly disperse the originally immiscible antibacterial essential oil and aqueous solution of gum arabic into countless tiny oil droplets to form a relatively stable, milk-like emulsion.

[0023] (b) Continue to maintain the water bath heating temperature of step (a), adjust the pH of the mixture to 4.0-6.0 with pH adjuster A (5-30 wt% sodium hydroxide aqueous solution), and react for 15-120 min. Then, cool the mixture to 0-10°C in an ice-water bath, and adjust the pH of the mixture to above 7 with pH adjuster A during the cooling process to alkalize it (the combination of cooling and alkalization is to terminate the above reaction. If only alkalization is performed without cooling, the size of the intermediate product obtained later will be uneven, or it may even break). Then, add glutaraldehyde aqueous solution dropwise to the mixture at a speed of 300-500 rpm and a drop rate of 1-2 mL / min. Then, centrifuge, filter, wash with water and freeze dry in sequence to obtain the intermediate product.

[0024] The ratio of the mass of the antibacterial essential oil to the total mass of gum arabic and chitosan is 1:0.67 to 1:1.5; the mass ratio of chitosan to gum arabic is 1:1 to 1:7; the mass of the emulsifier is 0.5% to 10% of the mass of the antibacterial essential oil; and the mass of glutaraldehyde is 2.5% to 5% of the total mass of chitosan and gum arabic.

[0025] The emulsifier is Tween 80, the concentration of gum arabic aqueous solution is 1~5wt%, the concentration of chitosan glacial acetic acid solution is 1~5wt%, and the concentration of glutaraldehyde aqueous solution is 20~25wt%.

[0026] Complex coagulation, a type of aqueous phase separation method, primarily utilizes the electrostatic interaction between two oppositely charged polymers to create cross-linking, causing the polymer to precipitate from the system and form microcapsules. Chitosan is a common cationic polysaccharide; in acidic solutions, the -NH2 group in the chitosan molecule combines with hydrogen ions to produce -NH4+. 3+ It carries a positive charge; gum arabic molecules have -COOH in their structure and are generally negatively charged in aqueous solution. Intermediate products are prepared using chitosan and gum arabic as wall materials.

[0027] Water bath heating has three functions: (I) accelerating the dissolution of gum arabic; (II) reducing the viscosity of the solution, making it easier to disperse essential oils and Tween 80 and facilitating the homogenization and emulsification of essential oils; and (III) maintaining the fluidity of the emulsion and improving the uniformity of the reaction between chitosan and gum arabic.

[0028] The specific process of coating the intermediate product with silica as described above is as follows: After dispersing the intermediate product in ultrapure water, tetraethyl orthosilicate is added dropwise at a rate of 1-2 mL / min while stirring at 300-500 rpm. Then, the pH of the system is adjusted to 2-3 using pH adjuster B (a 1-10 wt% hydrochloric acid aqueous solution). The mixture is then stirred at 300-500 rpm for 36-48 h at 30-40 °C. Afterward, the mixture is centrifuged, filtered, washed with water, and freeze-dried to obtain wear-resistant sustained-release microcapsules. The mass-to-volume ratio of the intermediate product to tetraethyl orthosilicate is 1 g: 2-6 mL.

[0029] The present invention also provides an application of abrasion-resistant sustained-release microcapsules as described in any of the preceding claims, wherein the abrasion-resistant sustained-release microcapsules are applied to a fabric by padding to obtain a highly abrasion-resistant and antifungal fabric.

[0030] As a preferred technical solution:

[0031] As described above, the specific preparation steps for the high abrasion-resistant and antifungal fabric are as follows:

[0032] (1) Clean the polyester-containing fabric, air dry it naturally, and then treat it in an ultraviolet crosslinker with an ultraviolet wavelength of 254nm and an energy of 90J for 0.5~9h. After that, soak it in a lipase solution with a concentration of 1~10g / L and let it stand at 25~60℃ for 0.5~9h.

[0033] (2) A finishing solution is obtained by mixing abrasion-resistant slow-release microcapsules, citric acid and ultrapure water, and the fabric obtained in step (1) is treated by two dips and two nips, and then baked to obtain a high abrasion-resistant and antifungal fabric; wherein, in the finishing solution, the content of abrasion-resistant slow-release microcapsules is 20~60g / L, the content of citric acid is 20~60g / L, the bath ratio is 1:10~40, the baking temperature is 110~150℃, and the baking time is 1~5min.

[0034] The current combat uniform is made of a polyester / cotton / vinyl alcohol ternary blend woven fabric with a blend ratio of 60 / 20 / 20. Since polyester accounts for 60% of the blend, and polyester fibers have few surface active groups and poor hydrophilicity, it is difficult to achieve satisfactory results during the finishing process. Therefore, in order to obtain a better antifungal finishing effect for the combat uniform fabric, the military combat uniform needs to be pretreated before microcapsule modification treatment.

[0035] The effects of treating polyester-containing fabrics with ultraviolet crosslinking and immersing them in lipase solution are the same: to break the ester bonds in the polyester macromolecules, generating polar groups, thereby improving the hydrophilicity and activation ability of the polyester fiber surface. The generated polar groups (-OH and -COOH) are hydrophilic and act as active sites, forming stable chemical bonds with the microcapsule wall material and crosslinking agent (citric acid). For example, the chitosan microcapsule wall material contains -NH2 and -OH, which can form hydrogen bonds with -COOH or -OH on the fiber surface, enhancing physical adsorption. The crosslinking agent (citric acid) used in the finishing process contains -COOH, which can undergo esterification or amidation reactions with the polar groups on the fiber surface and in the microcapsules, forming covalent bonds, thus firmly fixing the wear-resistant, slow-release microcapsules to the fiber.

[0036] The efficiency of using UV crosslinking or enzyme treatment (immersion in lipase solution) alone is very low. This invention uses both in series. UV treatment slightly disrupts the crystalline regions of the macromolecular chains on the fiber surface, making the fiber surface microscopically rough and partially relaxing the fiber structure. Then, enzyme treatment is used to allow enzyme molecules to penetrate deeper into the fiber (which is still part of the fiber surface compared to the large size of polyester fibers), improving the effect of enzyme treatment and thus increasing the fiber surface activity.

[0037] As described above, the high-abrasion-resistant antifungal fabric exhibits an antibacterial rate of 85.70–95.74% against Candida albicans and 83.05–95.10% against Trichophyton rubrum. The release of antibacterial essential oils from the abrasion-resistant sustained-release microcapsules in the fabric is slow. At 37°C, the initial release rate (first week) is relatively fast, with a release amount of 29.4%. As time progresses, the release rate slows down, but the release duration is longer. After 30 days at 37°C, the release rate of antibacterial essential oils from the abrasion-resistant sustained-release microcapsules is 34.70–37.04%. Due to the high essential oil content in the microcapsules at the initial release stage, the concentration difference between the inside and outside of the microcapsules is the largest, creating a strong diffusion driving force. As time progresses, the concentration difference between the inside and outside of the microcapsules decreases. The reduced pressure difference leads to a slower release rate, achieving a sustained release effect. After 50 cycles of friction under a load of 260g, the release rate of antibacterial essential oil in the abrasion-resistant sustained-release microcapsules of the high-abrasion-resistant antifungal fabric is 17.32%~23.32%; after 50 cycles of friction under a load of 595g, the release rate of antibacterial essential oil in the abrasion-resistant sustained-release microcapsules is 19.21%~24.09%; after 50 cycles of friction under a load of 795g, the release rate of antibacterial essential oil in the abrasion-resistant sustained-release microcapsules is 22.03%~27.87%; after 50 cycles of friction under a load of 795g, the high-abrasion-resistant antifungal fabric shows an inhibition rate of 70.18%~77.83% against Candida albicans and 69.89%~76.33% against Trichophyton rubrum.

[0038] The wear-resistant slow-release microcapsules in high wear-resistant and antifungal fabrics are more wear-resistant. In addition to their good mechanical properties (high strength and better toughness under shear force), the fabric surface has more active sites after ultraviolet radiation and enzyme pretreatment. The wear-resistant slow-release microcapsules can penetrate into the fabric gaps through the surface, greatly reducing the direct force during friction and making the wear-resistant slow-release microcapsules less prone to damage.

[0039] Different intensities of training will cause varying degrees of friction to clothing. These varying intensities of friction will generate different levels of shear force on the abrasion-resistant, sustained-release microcapsules. The greater the shear force, the greater the degree of rupture, and the more essential oils are released. Therefore, the higher the training intensity, the more antibacterial essential oils are released, and the better the antifungal effect.

[0040] Beneficial effects:

[0041] (1) A method for preparing wear-resistant sustained-release microcapsules according to the present invention is to synthesize CS-GA-SiO2 antifungal microcapsules by complex coagulation method, which is simple process.

[0042] (2) The wear-resistant sustained-release microcapsule of the present invention has a sustained-release effect and high friction durability.

[0043] (3) The application of a wear-resistant slow-release microcapsule of the present invention, the preparation of a high wear-resistant antifungal fabric, the release rate of essential oil in the microcapsules on the fabric increases with the increase of friction number and friction pressure, and the antifungal effect is better. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the synthesis of CS-GA microcapsules in Example 1;

[0045] Figure 2 This is a schematic diagram of the synthesis of CS-GA-SiO2 microcapsules in Example 1;

[0046] Figure 3 The diameter of the inhibition zone of Cnidium monnieri-Sophora flavescens compound essential oil at different volume ratios against Candida albicans (a) and Trichophyton rubrum (b);

[0047] Figure 4 The size and dispersion of CS-GA microcapsules at different emulsification times: 1 min (a), 3 min (b), 5 min (c), 8 min (d), and 10 min (e).

[0048] Figure 5The size and dispersion of CS-GA microcapsules under different Tween 80 dosages: 1% (a), 1.5% (b), 2% (c), 2.5% (d), 5% (e), and 10% (f);

[0049] Figure 6 The size and dispersion of CS-GA microcapsules at different emulsification speeds: 5000 rpm (a), 8000 rpm (b), 10000 rpm (c), 13000 rpm (d) and 15000 rpm (e).

[0050] Figure 7 The effect of wall material ratio on condensed phase yield, system transmittance (a) and system potential (b);

[0051] Figure 8 The effect of reaction pH on the yield of condensed phase, light transmittance of the system (a) and potential of the system (b) in the complex condensation process;

[0052] Figure 9 The effect of reaction time on the yield of condensed phase, light transmittance (a) and potential (b) of the system in the complex condensation process;

[0053] Figure 10 The effect of reaction temperature on the yield of condensed phase, light transmittance of the system (a) and potential of the system (b) in the complex condensation process;

[0054] Figure 11 The effect of tetraethyl orthosilicate dosage on microcapsule morphology was investigated; (a) tetraethyl orthosilicate dosage was 0; (b) the mass-to-volume ratio of intermediate product to tetraethyl orthosilicate was 1 g: 2 mL; (c) the mass-to-volume ratio of intermediate product to tetraethyl orthosilicate was 1 g: 4 mL; and (d) the mass-to-volume ratio of intermediate product to tetraethyl orthosilicate was 1 g: 6 mL.

[0055] Figure 12 The release curves of essential oils from CS-GA microcapsules and CS-GA-SiO2 microcapsules over time;

[0056] Figure 13 A schematic diagram of antifungal finishing on fabrics;

[0057] Figure 14 The effects of UV radiation time (a) and enzyme treatment time (b) on weight gain and strength of training uniform fabric (i.e., the high abrasion-resistant and antifungal fabric of this invention);

[0058] Figure 15 The effects of enzyme treatment temperature (a) and lipase concentration (b) on the weight gain and breaking strength of training uniform fabric;

[0059] Figure 16The effect of CS-GA-SiO2 microcapsule concentration on fabric weight gain;

[0060] Figure 17 The antibacterial rate of training uniform fabric treated with different concentrations of CS-GA-SiO2 microcapsules;

[0061] Figure 18 Antibacterial effects of training uniform fabric treated with CS-GA microcapsules against Candida albicans (A) and Trichophyton rubrum (B); microcapsule concentrations were 0 g / L (a), 20 g / L (b), 30 g / L (c), 40 g / L (d), 50 g / L (e) and 60 g / L (f).

[0062] Figure 19 The antibacterial rate of training uniform fabrics treated with different CS-GA microcapsule concentrations;

[0063] Figure 20 The frictional durability of microcapsules loaded on the training uniform fabric was tested; 260g, 595g and 795g were the release rates of CS-GA-SiO2 microcapsules at 260g, 595g and 795g, respectively.

[0064] Figure 21 The antibacterial effect of the training uniform fabric treated with CS-GA-SiO2 microcapsules in Example 1 on Candida albicans (A) and Trichophyton rubrum (B) after washing; the number of washes were 5 (b), 10 (c), 15 (d), 20 (e), and 30 (f), respectively. (a) is the untreated physical training uniform fabric.

[0065] Figure 22 The antibacterial rate of training uniform fabric under different washing cycles;

[0066] Figure 23 SEM image (a) and EDS elemental distribution map (b) of CS-GA-SiO2 microcapsules in Example 1;

[0067] Figure 24 The images show SEM images of the training uniform fabric before and after the microcapsule antifungal treatment in Example 7: (a) before treatment, (b) after treatment. Detailed Implementation

[0068] The present invention will be further described below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0069] Antifungal performance test: The antibacterial test was conducted in accordance with GB 20944.3-2008 "Evaluation of antibacterial properties of textiles - Part 3: Oscillation method" with appropriate modifications. The specific operation is as follows:

[0070] (1) Experimental preparation: Sterilize the pipette tips, centrifuge tubes, spreaders, PBS, SDA agar plates, etc. required for the experiment at 121℃ for 30 min. Place the remaining materials in a laminar flow hood for sterilization before use.

[0071] (2) The activated Candida albicans and Trichophyton rubrum were counted using a hemocytometer and diluted with PBS to a concentration of 2.5-3 × 10⁻⁶. 5 CFU / mL was used to obtain bacterial culture A.

[0072] (3) Take 0.05g of the treated fabric for testing, and take the untreated fabric as a control sample. Cut the two fabrics into pieces and put them into a test tube respectively. Then add 1mL of bacterial solution A to each test tube, mix well, and culture on a shaker at 30℃ and 200rpm for 18h to obtain the experimental bacterial solution and the control bacterial solution.

[0073] Take 0.1 mL of the experimental bacterial culture and the control bacterial culture respectively and perform the following operations: Incubate with PBS for 10... 1 10 2 and 10 3 After diluting the experimental or control bacterial suspension by 10 times, take 0.1 mL of each diluted suspension and spread it onto an SDA agar plate using a spreader. Prepare three parallel samples simultaneously, i.e., 10 1 10 2 and 10 3 Each of the three dilutions was plated once and incubated at 30°C for 24–48 hours. The colony counts that could be recorded using a bacterial counter were then recorded in the three parallel samples, thus obtaining W. t and Q t ;

[0074] W t Q represents the concentration of the control bacterial culture (CFU / mL). t The concentration of the bacterial culture in the experimental sample is (CFU / mL).

[0075] (4) Zero contact time: Take 0.1 mL of bacterial culture A and use PBS for 10 minutes. 1 10 2 and 10 3 Dilute 0.1 mL of the diluted bacterial culture A and spread it onto Sabouraud agar medium using a spreader. Prepare three parallel samples simultaneously, i.e., 10 samples each. 1 10 2 and 103 Each sample was diluted and spread once, then placed in an incubator at 30°C for 24-48 hours. The number of colonies that could be recorded using a bacterial counter was then recorded in the three parallel samples to obtain W0.

[0076] W0 represents the fungal concentration (CFU / mL) of the control sample at 0 contact time.

[0077] (5) Validity judgment: Calculate the growth value F of the test strain according to formula 1-1. For Candida albicans, the experiment is valid when F≥0.7.

[0078] (1-1);

[0079] (6) Antibacterial rate: The antibacterial rate Y of the test sample is calculated according to formula 1-2.

[0080] (1-2).

[0081] Friction durability test: The friction resistance of the fabric was tested according to GB / T 21196-2007 "Textiles - Martindale Method for Determination of Abrasion Resistance of Fabrics". Since the training uniform fabric has excellent abrasion resistance, the abrasive was replaced with 1000-grit sandpaper. The fabric was rubbed 50 times under three different weights (260g, 595g, and 795g) of loading blocks. The release rate of essential oil after different cycles of rubbing under different pressures was tested to evaluate the friction durability of the microcapsules on the fabric surface.

[0082] Washability test: The fabric was cut into 20cm*20cm pieces and hand-washed to simulate the actual washing method used by soldiers. The treated fabric was placed in deionized water and rubbed at room temperature (25±2℃) to ensure that the resultant force applied to the main rubbing direction of the fabric was between 200 and 300N. Every ten rubs were recorded as one washing cycle. After 5, 10, 15, 20, and 30 washing cycles, the fabric samples were dried at room temperature and then subjected to the antifungal washability test as described above to assess the antifungal washability of the training uniform fabric.

[0083] Tensile strength: The experiment was conducted according to GB / T 3923.1-2013 "Determination of tensile strength and elongation at break of fabrics - strip method". The fabric to be tested was cut into 5.5cm × 15cm pieces, and the yarns were unraveled along the edges until the sample width reached 5cm. Tensile testing was performed on a YG026MB electronic fabric tensile testing machine at a stretching rate of 100mm / min and a stretching interval of 100mm to obtain the tensile tensile strength of the modified pretreated fabric.

[0084] Antibacterial zone diameter: The antibacterial properties of the essential oil were tested using the filter paper disc method. Activated Candida albicans and Trichophyton rubrum were diluted to 2×10⁻⁶. 5CFU / mL, take 1 mL of bacterial suspension and disperse it on an SDA plate. After standing for 10 min to allow the bacterial suspension to settle, aspirate the excess liquid and dry the SDA agar plate. Disperse 10 μL of Cnidium monnieri and Sophora flavescens compound essential oils on filter paper at volume ratios of 6:1, 4:1, 2:1, 1:1, 1:2, 1:4, and 1:6, respectively. Use 10 μL of PBS (pH=7.4) as a control. Incubate Candida albicans at 30℃ for 48 h and Trichophyton rubrum at 30℃ for 4 days. Observe and measure the diameter of the inhibition zone around the filter paper; the larger the diameter, the better the antibacterial effect.

[0085] like Figure 3 As shown, the antibacterial effects of Cnidium monnieri and Sophora flavescens essential oils mixed at different volume ratios on Candida albicans and Trichophyton rubrum are observed. When the volume ratio of Cnidium monnieri to Sophora flavescens is 2:1 and 4:1, the antibacterial activity against Candida albicans is the highest, and the diameter of the inhibition zone is the largest. When the volume ratio of Cnidium monnieri to Sophora flavescens is 1:1 and 2:1, the antibacterial activity against Trichophyton rubrum is the highest.

[0086] The lipase used in this invention is from Bieder Pharmaceuticals, CAS number 9001-62-1; the gum arabic is from Ron Reagents, brand name R003199-500g; and the chitosan is from Maclean, brand name C804726-100g. Unless otherwise specified, all raw materials used in this invention are commercially available products well-known in the art, and unless explicitly limited, the solvent is assumed to be water.

[0087] Example 1

[0088] A method for preparing wear-resistant sustained-release microcapsules, the specific steps of which are as follows:

[0089] (1) When the antibacterial essential oil is in the form of emulsion droplets, an intermediate product is obtained by coating the surface of the antibacterial essential oil with an organic material that has water-swelling properties through the complex coagulation method;

[0090] (a) such as Figure 1 As shown, gum arabic was added to water to prepare a gum arabic aqueous solution under water bath heating to 50°C. Then, while maintaining the water bath heating temperature, antibacterial essential oil and Tween 80 were added to the 1 wt% gum arabic aqueous solution. The solution was emulsified at 8000 rpm for 3 min. Then, a chitosan glacial acetic acid solution was added dropwise at 1 mL / min at 8000 rpm to obtain a mixture.

[0091] The antibacterial essential oil was a mixture of Cnidium monnieri essential oil and Sophora flavescens essential oil in a volume ratio of 2:1; the mass ratio of the antibacterial essential oil to the total mass of gum arabic and chitosan was 1:1.12; the mass ratio of chitosan to gum arabic was 1:5.92; the mass of Tween 80 was 2.5% of the mass of the antibacterial essential oil; and the concentration of the chitosan glacial acetic acid solution was 1 wt%.

[0092] (b) Continue to maintain the water bath heating temperature of step (a), adjust the pH of the mixture to 4.8 with pH adjuster A (10wt% sodium hydroxide aqueous solution), and react for 30 min. Then, cool the mixture to 5°C and adjust the pH of the mixture to 8 with pH adjuster A during the cooling process. Then, add glutaraldehyde aqueous solution dropwise to the mixture at a speed of 400 rpm and a drop rate of 1.5 mL / min and continue stirring for 3 h. Then, centrifuge, filter, wash with water and freeze dry to obtain the intermediate product (CS-GA microcapsules).

[0093] The glutaraldehyde content is 2.5% of the total mass of chitosan and gum arabic; the concentration of the glutaraldehyde aqueous solution is 25 wt%.

[0094] (2) Coating the surface of the intermediate product with silica by the hydrolysis of tetraethyl orthosilicate;

[0095] like Figure 2 As shown, after dispersing the intermediate product in ultrapure water, tetraethyl orthosilicate was added dropwise at a rate of 1 mL / min while stirring at 500 rpm. The pH of the system was then adjusted to 2.5 using pH adjuster B (a 1 wt% hydrochloric acid aqueous solution). The mixture was then stirred at 500 rpm for 40 h at 35 °C. Subsequently, the mixture was centrifuged, filtered, washed with water, and freeze-dried to obtain wear-resistant sustained-release microcapsules (CS-GA-SiO2 microcapsules). The mass-to-volume ratio of the intermediate product to ultrapure water was 1 g:60 mL, and the mass-to-volume ratio of the intermediate product to tetraethyl orthosilicate was 1 g:4 mL.

[0096] The final wear-resistant sustained-release microcapsules have a core-shell structure, with the shell consisting of an inner shell and an outer shell. The core layer is an antibacterial essential oil, the inner shell is an organic material layer with water-swellable properties, and the outer shell is a silica layer. The organic material layer with water-swellable properties is a network structure formed by chitosan, gum arabic, and glutaraldehyde. Chitosan and gum arabic are connected by ionic bonds, while glutaraldehyde and chitosan are connected by covalent bonds. The core layer has a diameter of 0.93 μm, the inner shell has a thickness of 0.70 μm, and the outer shell has a thickness of 0.53 μm.

[0097] Some process parameters in step (1) were obtained through factor experiments, as follows:

[0098] like Figure 4 As shown, with increasing emulsification time, the emulsion droplets gradually become smaller. When the emulsification time is 3 minutes, the droplets are evenly dispersed and have a uniform particle size. With further extension of time, obvious demulsification was observed, and the particle size difference of CS-GA microcapsules gradually increased, with obvious unemulsified essential oil visible on the liquid surface. In conclusion, the optimal emulsification time is 3 minutes.

[0099] like Figure 5 As shown, when the amount of Tween 80 is 2.5% of the essential oil mass, the number of emulsion droplets increases, and the particle size difference is small, with droplets independently dispersed in the solution without aggregation. When the amount of Tween 80 is less than 2.5%, the particle size difference of the emulsion droplets is large, accompanied by partial aggregation. The addition of Tween 80 can significantly increase the stability of essential oil in gum arabic solution. However, when the amount of Tween 80 gradually increases to 10% of the essential oil mass, the particle size difference gradually increases with the increase of Tween 80, and droplet aggregation becomes obvious. In conclusion, using 2.5% of the essential oil mass of Tween 80 can achieve a good homogeneous emulsification effect.

[0100] like Figure 6 As shown, when the emulsification speed is 5000 rpm, the resulting emulsion droplets are of varying sizes. However, when the average speed is increased to 8000 rpm, the optimal emulsification effect is achieved, with uniformly dispersed droplets. With further increases in speed, the particle size difference increases, and the distribution becomes uneven, exhibiting significant agglomeration, which is detrimental to the re-coagulation reaction. In conclusion, Tween 80 achieves a good homogeneous emulsification effect at an emulsification speed of 8000 rpm.

[0101] like Figure 7 As shown, with the increase of gum arabic dosage, the potential in the system after the reaction gradually decreases, indicating that when the CS:GA ratio varies from 1:1 to 1:5, the charge in the system cannot reach equilibrium, and the coagulation reaction fails to occur completely. Correspondingly, with the gradual increase of gum arabic dosage, the yield of the condensed phase gradually increases. When the CS:GA ratio reaches 1:6, the system yield reaches its maximum, and the transmittance of the supernatant is at its maximum, indicating that the maximum coagulation reaction occurs at this point. When the CS:GA ratio is further increased, the yield decreases instead, and the potential becomes negative, indicating that the chitosan in the system has completely undergone a secondary coagulation reaction, and there is excess gum arabic. Therefore, it can be considered that in this reaction system, when the CS:GA ratio is 1:6 to 1:7, the amount of charge in the solution reaches equilibrium.

[0102] like Figure 8 As shown, Figure 8Figure (a) shows the effect of pH on the yield and transmittance of the system. When the pH of the system is between 4.5 and 5.0, the coagulation reaction occurs well, and both the yield and transmittance of the condensed phase are relatively high. When the pH of the system is 4.5, the yield and transmittance are the highest, indicating that the coagulation reaction occurs to the greatest extent at this point, and the condensed phase is the most stable. When the pH of the system is below 4.5, the yield of the condensed phase decreases, which may be due to the presence of H+ in the solution. + This is due to the inhibition of carboxyl ionization in gum arabic, which affects the electrostatic interaction between the two. Figure 8 (b) shows the effect of pH ratio on the system potential. The experimental results further show that when the pH is below 4.5, there are more positive charges in the system and the amino protonation is obvious; when the pH is above 5.0, the negative charges in the system gradually increase, indicating that the amino protonation of chitosan is weakened at this time, the degree of carboxyl ionization in gum arabic increases, thereby inhibiting the formation of condensed phase and the yield of condensed phase also decreases accordingly.

[0103] like Figure 9 As shown, when the reaction time is 15 min, the system yield is low and the zeta potential is high, indicating that chitosan and gum arabic are reacting at this time. When the reaction time is greater than 30 min, the system yield and transmittance reach their maximum. With the extension of time, the system yield and transmittance decrease slightly, and the zeta potential does not change significantly, indicating that the reaction of the two wall materials is almost complete at 30 min. Therefore, the optimal time for the complex coagulation reaction can be determined to be 30 min.

[0104] like Figure 10 As shown, the system yield increases significantly with increasing reaction temperature, indicating that higher temperature favors the complex condensation reaction. At lower temperatures, the complex condensation reaction may be insufficient due to slow molecular motion. When the temperature increases to 60℃, the yield decreases, and the system potential increases significantly, indicating that intermolecular motion intensifies at this temperature, leading to the disruption of intermolecular forces. The resulting condensed phase is unstable, and the product is dispersed in the solution, making separation by centrifugation impossible. At a reaction temperature of 50℃, the zeta potential is lowest, along with the system yield and transmittance, indicating that the complex condensation reaction can occur to the greatest extent possible.

[0105] Some process parameters in step (2) were obtained through factor experiments, as follows:

[0106] like Figure 11As shown, when the mass-to-volume ratio of intermediate product to tetraethyl orthosilicate is 1 g:2 mL, the microcapsule surface shows obvious damage and poor strength. This may be due to the addition of hydrochloric acid during the reaction, which damages the CS-GA microcapsule structure, and the silica generated from the hydrolysis of tetraethyl orthosilicate is insufficient to repair the damaged microcapsules. When the mass-to-volume ratio of intermediate product to tetraethyl orthosilicate is 1 g:6 mL, silica particles are found on the microcapsule surface, and the silica distribution is uneven. When the mass-to-volume ratio of intermediate product to tetraethyl orthosilicate is 1 g:4 mL, the CS-GA-SiO2 microcapsules are uniform in size, well dispersed, and have a smooth surface.

[0107] from Figure 23 As shown in (a), when the mass-to-volume ratio of the intermediate product to tetraethyl orthosilicate is 1 g:4 mL, the CS-GA-SiO2 microcapsules are uniform in size, well-dispersed, and have a smooth surface. Figure 23 Figure (b) shows that the surface silicon element distribution is consistent with the microcapsule distribution in Figure (a), indicating the successful preparation of CS-GA-SiO2 microcapsules.

[0108] Comparative Example 1

[0109] A method for preparing microcapsules is basically the same as in Example 1, except that step (1) is omitted and silica is directly coated on the surface of the antibacterial essential oil.

[0110] Comparative Example 2

[0111] A method for preparing CS-GA microcapsules is basically the same as in Example 1, except that step (2) is omitted.

[0112] like Figure 12 As shown, the release of essential oils from the CS-GA microcapsules in Comparative Example 2 and the CS-GA-SiO2 microcapsules in Example 1 exhibits a slow release pattern. At a relatively high human-adaptable temperature of 37°C, the release rate is faster in the initial stage (first week), with release amounts of 29.8% and 29.4% for the CS-GA and CS-GA-SiO2 microcapsules, respectively. As time progresses, the release rate slows down, and the sustained release time is longer. After 30 days at 37°C, the total release amounts are 35.5% and 35.1%, respectively. This is mainly because the high essential oil content in the microcapsules at the initial stage leads to relatively vigorous molecular movement and significant release. As time progresses, the concentration difference between the internal and external essential oils decreases, resulting in a slower release rate and achieving sustained release. Notably, the release rate of the double-layered CS-GA-SiO2 microcapsules, due to the presence of a layer of silica particles on their surface, is slightly lower than that of the single-layered CS-GA microcapsules at different times.

[0113] Example 2

[0114] A method for preparing wear-resistant sustained-release microcapsules, the specific steps of which are as follows:

[0115] (1) When the antibacterial essential oil is in the form of emulsion droplets, an intermediate product is obtained by coating the surface of the antibacterial essential oil with an organic material that has water-swelling properties through the complex coagulation method;

[0116] (a) Gum arabic was added to water to prepare an aqueous solution of gum arabic under water bath heating to 30°C. Then, while maintaining the water bath heating temperature, antibacterial essential oil and Tween 80 were added to the 1 wt% aqueous solution of gum arabic. The mixture was emulsified at 5000 rpm for 1 min. Then, a glacial acetic acid solution of chitosan was added dropwise at 1.2 mL / min at 5000 rpm to obtain a mixture.

[0117] The antibacterial essential oil is a mixture of Cnidium monnieri essential oil and Sophora flavescens essential oil in a volume ratio of 6:1; the mass ratio of the antibacterial essential oil to the total mass of gum arabic and chitosan is 1:1.5; the mass ratio of chitosan to gum arabic is 1:1; the mass of Tween 80 is 1% of the mass of the antibacterial essential oil; and the concentration of the glacial acetic acid solution of chitosan is 1 wt%.

[0118] (b) Continue to maintain the water bath heating temperature of step (a), adjust the pH of the mixture to 4 with pH adjuster A (5wt% sodium hydroxide aqueous solution) and react for 15 min. Then cool the mixture to 0°C and adjust the pH of the mixture to 7 with pH adjuster A during the cooling process. Then add glutaraldehyde aqueous solution dropwise to the mixture at a speed of 300 rpm and a drop rate of 2 mL / min and continue stirring for 1 h. Then centrifuge, filter, wash with water and freeze dry to obtain the intermediate product.

[0119] The glutaraldehyde content is 3 wt% of the total mass of chitosan and gum arabic; the concentration of the glutaraldehyde aqueous solution is 20 wt%.

[0120] (2) Coating the surface of the intermediate product with silica by the hydrolysis of tetraethyl orthosilicate;

[0121] After dispersing the intermediate product in ultrapure water, tetraethyl orthosilicate was added dropwise at a rate of 2 mL / min while stirring at 300 rpm. The pH of the system was then adjusted to 2 using pH adjuster B (a 2 wt% hydrochloric acid aqueous solution). The mixture was then stirred at 300 rpm for 48 h at 30 °C. Subsequently, the mixture was centrifuged, filtered, washed with water, and freeze-dried to obtain wear-resistant sustained-release microcapsules. The mass-to-volume ratio of the intermediate product to ultrapure water was 1 g:40 mL, and the mass-to-volume ratio of the intermediate product to tetraethyl orthosilicate was 1 g:2 mL.

[0122] The final wear-resistant sustained-release microcapsules have a core-shell structure, with the shell consisting of an inner shell and an outer shell. The core layer is an antibacterial essential oil, the inner shell is an organic material layer with water-swellable properties, and the outer shell is a silica layer. The organic material layer with water-swellable properties is a network structure formed by chitosan, gum arabic, and glutaraldehyde. Among them, chitosan and gum arabic are connected by ionic bonds, and glutaraldehyde and chitosan are connected by covalent bonds. The diameter of the core layer is 1.35 μm, the thickness of the inner shell is 0.85 μm, and the thickness of the outer shell is 0.28 μm.

[0123] Example 3

[0124] A method for preparing wear-resistant sustained-release microcapsules, the specific steps of which are as follows:

[0125] (1) When the antibacterial essential oil is in the form of emulsion droplets, an intermediate product is obtained by coating the surface of the antibacterial essential oil with an organic material that has water-swelling properties through the complex coagulation method;

[0126] (a) Gum arabic was added to water to prepare an aqueous solution of gum arabic under water bath heating to 35°C. Then, while maintaining the water bath heating temperature, antibacterial essential oil and Tween 80 were added to the 2wt% aqueous solution of gum arabic. The mixture was emulsified at 10,000 rpm for 3 min. Then, a glacial acetic acid solution of chitosan was added dropwise at 8,000 rpm at a rate of 1.5 mL / min to obtain a mixture.

[0127] The antibacterial essential oil was a mixture of Cnidium monnieri essential oil and Sophora flavescens essential oil in a volume ratio of 4:1; the mass ratio of the antibacterial essential oil to the total mass of gum arabic and chitosan was 1:1.085; the mass ratio of chitosan to gum arabic was 1:2; the mass of Tween 80 was 1.5% of the mass of the antibacterial essential oil; and the concentration of the chitosan glacial acetic acid solution was 2 wt%.

[0128] (b) Continue to maintain the water bath heating temperature of step (a), adjust the pH of the mixture to 4.5 with pH adjuster A (15wt% sodium hydroxide aqueous solution) and react for 30 min. Then, cool the mixture to 3°C and adjust the pH of the mixture to 7.5 with pH adjuster A during the cooling process. Then, add glutaraldehyde aqueous solution dropwise to the mixture at a speed of 350 rpm and a drop rate of 1.75 mL / min and continue stirring for 2 h. Then, centrifuge, filter, wash with water and freeze dry to obtain the intermediate product.

[0129] The glutaraldehyde content was 3.5% of the total mass of chitosan and gum arabic; the concentration of the glutaraldehyde aqueous solution was 21 wt%.

[0130] (2) Coating the surface of the intermediate product with silica by the hydrolysis of tetraethyl orthosilicate;

[0131] After dispersing the intermediate product in ultrapure water, tetraethyl orthosilicate was added dropwise at a rate of 1.75 mL / min while stirring at 350 rpm. The pH of the system was then adjusted to 2.2 using pH adjuster B (4 wt% hydrochloric acid aqueous solution). The mixture was then stirred at 350 rpm for 46 h at 32 °C. Subsequently, the mixture was centrifuged, filtered, washed with water, and freeze-dried to obtain wear-resistant sustained-release microcapsules. The mass-to-volume ratio of the intermediate product to ultrapure water was 1 g: 50 mL, and the mass-to-volume ratio of the intermediate product to tetraethyl orthosilicate was 1 g: 3 mL.

[0132] The final wear-resistant sustained-release microcapsules have a core-shell structure, with the shell consisting of an inner shell and an outer shell. The core layer is an antibacterial essential oil, the inner shell is an organic material layer with water-swellable properties, and the outer shell is a silica layer. The organic material layer with water-swellable properties is a network structure formed by chitosan, gum arabic, and glutaraldehyde. Among them, chitosan and gum arabic are connected by ionic bonds, and glutaraldehyde and chitosan are connected by covalent bonds. The diameter of the core layer is 0.89 μm, the thickness of the inner shell is 0.68 μm, and the thickness of the outer shell is 0.39 μm.

[0133] Example 4

[0134] A method for preparing wear-resistant sustained-release microcapsules, the specific steps of which are as follows:

[0135] (1) When the antibacterial essential oil is in the form of emulsion droplets, an intermediate product is obtained by coating the surface of the antibacterial essential oil with an organic material that has water-swelling properties through the complex coagulation method;

[0136] (a) Gum arabic was added to water to prepare an aqueous solution of gum arabic under water bath heating to 40°C. Then, while maintaining the water bath heating temperature, antibacterial essential oil and Tween 80 were added to the 3wt% aqueous solution of gum arabic. The mixture was emulsified at 12000 rpm for 5 min. Then, a glacial acetic acid solution of chitosan was added dropwise at 10000 rpm at a dropping rate of 1.6 mL / min to obtain a mixture.

[0137] The antibacterial essential oil was a mixture of Cnidium monnieri essential oil and Sophora flavescens essential oil in a 1:1 volume ratio; the mass ratio of the antibacterial essential oil to the total mass of gum arabic and chitosan was 1:0.67; the mass ratio of chitosan to gum arabic was 1:3; the mass of Tween 80 was 2.5% of the mass of the antibacterial essential oil; and the concentration of the chitosan glacial acetic acid solution was 3 wt%.

[0138] (b) Continue to maintain the water bath heating temperature of step (a), adjust the pH of the mixture to 5 with pH adjuster A (20wt% sodium hydroxide aqueous solution) and react for 60 min. Then, cool the mixture to 6°C and adjust the pH of the mixture to 8 with pH adjuster A during the cooling process. Then, add glutaraldehyde aqueous solution dropwise to the mixture at a speed of 450 rpm and a drop rate of 1.5 mL / min and continue stirring for 3 h. Then, centrifuge, filter, wash with water and freeze dry to obtain the intermediate product.

[0139] The glutaraldehyde content is 4% of the total mass of chitosan and gum arabic; the concentration of the glutaraldehyde aqueous solution is 22 wt%.

[0140] (2) Coating the surface of the intermediate product with silica by the hydrolysis of tetraethyl orthosilicate;

[0141] After dispersing the intermediate product in ultrapure water, tetraethyl orthosilicate was added dropwise at a rate of 1.5 mL / min while stirring at 400 rpm. The pH of the system was then adjusted to 2.3 using pH adjuster B (6 wt% hydrochloric acid aqueous solution). The mixture was then stirred at 400 rpm for 44 h at 35 °C. Subsequently, the mixture was centrifuged, filtered, washed with water, and freeze-dried to obtain wear-resistant sustained-release microcapsules. The mass-to-volume ratio of the intermediate product to ultrapure water was 1 g: 60 mL, and the mass-to-volume ratio of the intermediate product to tetraethyl orthosilicate was 1 g: 4 mL.

[0142] The final wear-resistant sustained-release microcapsules have a core-shell structure, with the shell consisting of an inner shell and an outer shell. The core layer is an antibacterial essential oil, the inner shell is an organic material layer with water-swellable properties, and the outer shell is a silica layer. The organic material layer with water-swellable properties is a network structure formed by chitosan, gum arabic, and glutaraldehyde. Chitosan and gum arabic are connected by ionic bonds, while glutaraldehyde and chitosan are connected by covalent bonds. The core layer has a diameter of 0.76 μm, the inner shell has a thickness of 0.53 μm, and the outer shell has a thickness of 0.47 μm.

[0143] Example 5

[0144] A method for preparing wear-resistant sustained-release microcapsules, the specific steps of which are as follows:

[0145] (1) When the antibacterial essential oil is in the form of emulsion droplets, an intermediate product is obtained by coating the surface of the antibacterial essential oil with an organic material that has water-swelling properties through the complex coagulation method;

[0146] (a) Gum arabic was added to water to prepare an aqueous solution of gum arabic under water bath heating to 45°C. Then, while maintaining the water bath heating temperature, antibacterial essential oil and Tween 80 were added to the 4 wt% aqueous solution of gum arabic. The mixture was emulsified at 13,000 rpm for 8 min. Then, a glacial acetic acid solution of chitosan was added dropwise at 1.8 mL / min at 13,000 rpm to obtain a mixed solution.

[0147] The antibacterial essential oil is a mixture of Cnidium monnieri essential oil and Sophora flavescens essential oil in a volume ratio of 1:4; the mass ratio of the antibacterial essential oil to the total mass of gum arabic and chitosan is 1:1; the mass ratio of chitosan to gum arabic is 1:4; the mass of Tween 80 is 5% of the mass of the antibacterial essential oil; and the concentration of the chitosan glacial acetic acid solution is 4 wt%.

[0148] (b) Continue to maintain the water bath heating temperature of step (a), adjust the pH of the mixture to 5.5 with pH adjuster A (25wt% sodium hydroxide aqueous solution) and react for 90 min. Then, cool the mixture to 8°C and adjust the pH of the mixture to 8.5 with pH adjuster A during the cooling process. Then, add glutaraldehyde aqueous solution dropwise to the mixture at a speed of 475 rpm and a drop rate of 1.25 mL / min and continue stirring for 4 h. Then, centrifuge, filter, wash with water and freeze dry to obtain the intermediate product.

[0149] The glutaraldehyde content was 4.5% of the total mass of chitosan and gum arabic; the concentration of the glutaraldehyde aqueous solution was 23 wt%.

[0150] (2) Coating the surface of the intermediate product with silica by the hydrolysis of tetraethyl orthosilicate;

[0151] After dispersing the intermediate product in ultrapure water, tetraethyl orthosilicate was added dropwise at a rate of 1.25 mL / min while stirring at 450 rpm. The pH of the system was then adjusted to 2.8 using pH adjuster B (8 wt% hydrochloric acid aqueous solution). The mixture was then stirred at 450 rpm for 42 h at 38 °C. Subsequently, the mixture was centrifuged, filtered, washed with water, and freeze-dried to obtain wear-resistant sustained-release microcapsules. The mass-to-volume ratio of the intermediate product to ultrapure water was 1 g:70 mL, and the mass-to-volume ratio of the intermediate product to tetraethyl orthosilicate was 1 g:5 mL.

[0152] The final wear-resistant sustained-release microcapsules have a core-shell structure, with the shell consisting of an inner shell and an outer shell. The core layer is an antibacterial essential oil, the inner shell is an organic material layer with water-swellable properties, and the outer shell is a silica layer. The organic material layer with water-swellable properties is a network structure formed by chitosan, gum arabic, and glutaraldehyde. Among them, chitosan and gum arabic are connected by ionic bonds, and glutaraldehyde and chitosan are connected by covalent bonds. The diameter of the core layer is 0.68 μm, the thickness of the inner shell is 1.34 μm, and the thickness of the outer shell is 0.68 μm.

[0153] Example 6

[0154] A method for preparing wear-resistant sustained-release microcapsules, the specific steps of which are as follows:

[0155] (1) When the antibacterial essential oil is in the form of emulsion droplets, an intermediate product is obtained by coating the surface of the antibacterial essential oil with an organic material that has water-swelling properties through the complex coagulation method;

[0156] (a) Gum arabic was added to water to prepare an aqueous solution of gum arabic under water bath heating to 60°C. Then, while maintaining the water bath heating temperature, antibacterial essential oil and Tween 80 were added to the 5 wt% aqueous solution of gum arabic. The mixture was emulsified at 15,000 rpm for 10 min. Then, a glacial acetic acid solution of chitosan was added dropwise at 2 mL / min at 15,000 rpm to obtain a mixture.

[0157] The antibacterial essential oil is a mixture of Cnidium monnieri essential oil and Sophora flavescens essential oil in a volume ratio of 1:6; the mass ratio of the antibacterial essential oil to the total mass of gum arabic and chitosan is 1:1.25; the mass ratio of chitosan to gum arabic is 1:5; the mass of Tween 80 is 10% of the mass of the antibacterial essential oil; and the concentration of the chitosan glacial acetic acid solution is 5 wt%.

[0158] (b) Continue to maintain the water bath heating temperature of step (a), adjust the pH of the mixture to 6 with pH adjuster A (30wt% sodium hydroxide aqueous solution) and react for 120 min. Then, cool the mixture to 10°C and adjust the pH of the mixture to 9 with pH adjuster A during the cooling process. Then, add glutaraldehyde aqueous solution dropwise to the mixture at a speed of 500 rpm and a drop rate of 1 mL / min and continue stirring for 5 h. Then, centrifuge, filter, wash with water and freeze dry to obtain the intermediate product.

[0159] The glutaraldehyde content is 5% of the total mass of chitosan and gum arabic, and the concentration of the glutaraldehyde aqueous solution is 24 wt%.

[0160] (2) Coating the surface of the intermediate product with silica by the hydrolysis of tetraethyl orthosilicate;

[0161] After dispersing the intermediate product in ultrapure water, tetraethyl orthosilicate was added dropwise at a rate of 1 mL / min while stirring at 500 rpm. The pH of the system was then adjusted to 3 using pH adjuster B (a 10 wt% hydrochloric acid aqueous solution). The mixture was then stirred at 500 rpm for 36 h at 40 °C. Subsequently, the mixture was centrifuged, filtered, washed with water, and freeze-dried to obtain wear-resistant sustained-release microcapsules. The mass-to-volume ratio of the intermediate product to ultrapure water was 1 g: 80 mL, and the mass-to-volume ratio of the intermediate product to tetraethyl orthosilicate was 1 g: 6 mL.

[0162] The final wear-resistant sustained-release microcapsules have a core-shell structure, with the shell consisting of an inner shell and an outer shell. The core layer is an antibacterial essential oil, the inner shell is an organic material layer with water-swellable properties, and the outer shell is a silica layer. The organic material layer with water-swellable properties is a network structure formed by chitosan, gum arabic, and glutaraldehyde. Among them, chitosan and gum arabic are connected by ionic bonds, and glutaraldehyde and chitosan are connected by covalent bonds. The diameter of the core layer is 0.62 μm, the thickness of the inner shell is 0.31 μm, and the thickness of the outer shell is 0.81 μm.

[0163] Example 7

[0164] An application of wear-resistant sustained-release microcapsules, such as Figure 13 As shown, the abrasion-resistant slow-release microcapsules of Example 1 were applied to the fabric by padding to obtain a highly abrasion-resistant and antifungal fabric. The specific steps are as follows:

[0165] (1) Clean the polyester-containing fabric, air dry it naturally, and then treat it in an ultraviolet crosslinker with an ultraviolet wavelength of 254nm and an energy of 90J for 2 hours. After that, soak it in a lipase solution with a concentration of 2g / L and let it stand at 30℃ for 6 hours.

[0166] (2) A finishing solution is obtained by mixing abrasion-resistant slow-release microcapsules, citric acid and ultrapure water, and the fabric obtained in step (1) is treated by two dips and two nips, and then baked to obtain a high abrasion-resistant and antifungal fabric; wherein, the content of abrasion-resistant slow-release microcapsules in the finishing solution is 50 g / L, the content of citric acid is 40 g / L, the bath ratio is 1:40, the baking temperature is 120℃, and the baking time is 3 min.

[0167] The final high-abrasion-resistant antifungal fabric exhibited an inhibition rate of 93.90% against Candida albicans and 92.03% against Trichophyton rubrum. After being placed at 37°C for 30 days, the release rate of antibacterial essential oil from the abrasion-resistant sustained-release microcapsules was 35.02%. After 50 cycles of friction under a load of 260g, the release rate was 20.01%. After 50 cycles of friction under a load of 595g, the release rate was 21.92%. After 50 cycles of friction under a load of 795g, the release rate was 24.95%. After 50 cycles of friction under a load of 795g, the high-abrasion-resistant antifungal fabric showed an inhibition rate of 75.53% against Candida albicans and 74.93% against Trichophyton rubrum.

[0168] Depend on Figure 14 As shown in (a), under otherwise constant conditions, the fabric weight gain increases and the strength decreases with prolonged UV irradiation time. When the UV irradiation time is 4 hours, the fabric breaking strength drops below 1400 N, which does not meet the strength requirements for military-grade training uniforms. Therefore, to maximize the loading of microcapsules while minimizing the impact on fabric strength, the optimal UV irradiation time for training uniforms is 2 hours, at which point the strength of the training uniform is 1415 N. Figure 14 As shown in (b), under the conditions of 2 hours of UV irradiation, 30°C of enzyme treatment, and 2 g / L of lipase, the fabric weight gain rate showed a linear correlation with the enzyme treatment time. The longer the enzyme treatment time, the greater the microcapsule loading. When the enzyme treatment time exceeded 6 hours, the microcapsule loading rate tended to level off. This may be due to the hydrolysis of polyester fiber ester bonds caused by the extended reaction time. Furthermore, after 6 hours, the number of hydrolyzable ester bonds on the fiber surface decreased, hence the gradual flattening of the trend. At a treatment time of 6 hours, the strength of the treated training uniform fabric exceeded 1400 N, and the maximum microcapsule loading was achieved at this time. Therefore, the optimal enzyme treatment time for the training uniform was 6 hours.

[0169] like Figure 15 As shown in Figure (a), under the conditions of 6 hours of enzyme treatment, 2 g / L of lipase, and 2 hours of UV pretreatment, changing the enzyme treatment temperature revealed that the loading capacity of microcapsules first increased and then decreased with increasing temperature. Conversely, the strength of the treated fabric first decreased and then increased. This is because temperature has a bidirectional effect on lipase activity; higher temperatures promote increased enzyme activity, but excessively high temperatures can lead to enzyme inactivation or denaturation, preventing it from hydrolyzing ester bonds. Figure 15As shown in (b), the fabric strength first decreases and then increases with the increase of lipase concentration. This may be because when the enzyme concentration is low, the increase of concentration is conducive to the binding of lipase to the active sites on the fiber surface, thereby hydrolyzing the fiber. When the concentration is high enough, there are not enough active sites on the fiber surface, and the enzyme cannot enter the fiber to react. Therefore, its catalytic hydrolysis efficiency decreases, which leads to a decrease in the loading rate of microcapsules. When the lipase concentration is 2 g / L, the fabric modification effect is the best and the microcapsule loading is the largest.

[0170] like Figure 16 As shown, the fabric weight gain rate is linearly correlated with the concentration of CS-GA-SiO2 microcapsules, and increasing the microcapsule concentration is beneficial for the loading of microcapsules onto the fabric surface. However, an increase in the microcapsule loading rate leads to a decrease in fabric comfort; therefore, the amount of microcapsules used should be minimized while meeting antifungal requirements. Subsequent tests will examine the antifungal properties of training uniforms treated with different concentrations of microcapsules to determine the optimal dosage.

[0171] like Figure 17 As shown, the antibacterial properties of the training uniform fabric loaded with CS-GA-SiO2 microcapsules significantly improved with increasing microcapsule concentration. When the CS-GA-SiO2 microcapsule concentration reached 50 g / L, the inhibition rate against both pathogenic fungi reached over 90%, meeting the antibacterial rate requirements (≥80%) for Trichophyton rubrum and Candida albicans in the QB / T2881-2013 standard "Technical Conditions for Antibacterial Performance of Footwear and Footwear Components". Therefore, a CS-GA-SiO2 microcapsule concentration of 50 g / L was selected for antifungal finishing of the training uniform fabric.

[0172] Figure 21 and Figure 22 The images show the antibacterial effect and antibacterial rate of the training uniform fabric after different washing cycles. Similar to the physical training uniform fabric, the antibacterial rate of the fabric decreases with increasing washing cycles. This may be because with increasing washing cycles, microcapsules on the fabric surface gradually detach, and microcapsules deep inside the fabric rupture under pressure, reducing the amount of antifungal active ingredients and thus decreasing the antibacterial rate. After 20 washes, the antibacterial rate of the training uniform fabric against Candida albicans remains at 75%. After 30 washes, the antibacterial rate against Trichophyton rubrum still reaches over 70%, still meeting the requirements for antibacterial fabrics.

[0173] In conclusion, the addition of a silica shell does not affect the antibacterial effect of the microcapsules. The training uniforms treated with CS-GA-SiO2 microcapsules have excellent antifungal durability and can meet the requirements for long-term use in missions.

[0174] like Figure 24As shown, after being treated with CS-GA-SiO2 microcapsules, the fiber surface is covered with a layer of microcapsules, and some microcapsules penetrate into the gaps in the fabric, thus giving the training uniform a long-lasting antifungal function.

[0175] Comparative Example 3

[0176] The application of a microcapsule is basically the same as in Example 7, except that the wear-resistant sustained-release microcapsule of Example 1 is replaced with the microcapsule of Comparative Example 1.

[0177] The final antifungal fabric exhibited an inhibition rate of 83.55% against Candida albicans and 80.34% against Trichophyton rubrum. After being placed at 37°C for 30 days, the release rate of antibacterial essential oil from the microcapsules was 29.16%. After 50 rubs under a load of 260g, the release rate was 18.02%. After 50 rubs under a load of 595g, the release rate was 19.94%. After 50 rubs under a load of 795g, the release rate was 22.65%. After 50 rubs under a load of 795g, the antifungal fabric showed an inhibition rate of 66.36% against Candida albicans and 64.90% against Trichophyton rubrum.

[0178] Comparing Comparative Example 3 and Example 7, it can be found that the antibacterial rate of Comparative Example 3 and the antibacterial rate after 50 rubs are both lower than those of Example 7. This is because Comparative Example 3 does not have an organic shell, making drug release more difficult.

[0179] Comparative Example 4

[0180] The application of a microcapsule is basically the same as in Example 7, except that the wear-resistant sustained-release microcapsule of Example 1 is replaced with the microcapsule of Comparative Example 2.

[0181] The final antifungal fabric showed an inhibition rate of 96.70% against Candida albicans and 92.60% against Trichophyton rubrum. After being placed at 37°C for 30 days, the release rate of antibacterial essential oil from the microcapsules was 36.53%. After being rubbed 50 times under a load of 795g, the release rate of antibacterial essential oil from the microcapsules was 35.12%.

[0182] Comparing Comparative Example 4 and Example 7, it can be found that the antibacterial rates of Example 7 and Comparative Example 4 are almost the same. However, after 50 rubs under a load of 795g, the release rate of the antibacterial essential oil in Comparative Example 4 is much greater than that in Example 7. This is because the microcapsules in Example 7 have an inorganic silica layer that provides excellent wear resistance, while Comparative Example 4 has no silica layer, resulting in its wear resistance being inferior to that of Example 7.

[0183] The antibacterial effects of fabrics treated with different concentrations of CS-GA microcapsules on Candida albicans and Trichophyton rubrum were tested using the oscillation method. The test results are as follows: Figure 18 and Figure 19 As shown in the figure. Experiments revealed that untreated training uniform fabric lacked antifungal properties, while the survival rate of fungi decreased with increasing microcapsule concentration in treated fabrics. When the CS-GA microcapsule dosage reached 40 g / L (corresponding to response ratio 4), the fabric's inhibition rates against *Candida albicans* and *Trichophyton rubrum* were 96.7% and 92.6%, respectively, far exceeding the antibacterial rate requirements for *Candida albicans* (≥60%) in the national standard GB / T20944.3-2008 "Evaluation of Antimicrobial Properties of Textiles Part 3: Shaking Method" and the antimicrobial rate requirements for *Candida albicans* (≥80%) in the standard QB / T2881-2013 "Technical Conditions for Antimicrobial Properties of Footwear and Footwear Components". With increasing CS-GA microcapsule concentration, the microcapsule loading rate on the fabric gradually increased, and the fabric's antibacterial rate also increased accordingly. However, when the CS-GA microcapsule concentration exceeded 40 g / L, the maximum microcapsule loading rate was reached, therefore the antibacterial rate did not increase significantly.

[0184] The fabric's abrasion resistance was tested according to GB / T21196-2007 "Textiles - Martindale Method for Determination of Abrasion Resistance of Fabrics". Figure 20 As can be seen, the release of essential oils from the microcapsules in the training uniform fabric (i.e., high abrasion-resistant and antifungal fabric) treated with CS-GA-SiO2 microcapsules gradually increases with the number of friction cycles. Using 1000-grit sandpaper as the abrasive, after 50 cycles of friction with loading blocks of 260g, 595g, and 795g respectively, the essential oil release reached 20.01%, 21.92%, and 24.95%, respectively, demonstrating good friction durability. This may be due to the high strength of the double-layer CS-GA-SiO2 microcapsules, resulting in better toughness under shear force; on the other hand, it may be due to the increased number of active sites on the fabric surface after UV radiation and enzyme pretreatment, allowing some microcapsules to penetrate deep into the fabric gaps, thus significantly reducing the direct force during friction. Increased pressure leads to increased release of essential oils from the microcapsules. This may be due to the increased shear force experienced by the fabric and lining during friction, causing the CS-GA-SiO2 microcapsule shells to rupture under shear force, releasing the internal essential oils. Therefore, the release of antifungal essential oils from the fabric varies under different training intensities, and the antifungal effect increases accordingly with increasing training intensity. After 50 cycles of vigorous friction under a load of 795g, the antifungal rates of the training uniform fabric against Candida albicans and Trichophyton rubrum remained at 75.53% and 74.93%, respectively, exceeding the national standard requirement for antifungal fabrics (60%). Therefore, the antifungal fabric exhibits good friction durability.

[0185] Comparative Example 5

[0186] The application of a wear-resistant sustained-release microcapsule is basically the same as in Example 7, except that the treatment time in the UV crosslinker in step (1) is 8 hours and the lipase solution is not soaked.

[0187] Compared to Example 7, the strength of the training uniform fabric in this case was 1492.3 N, and the weight gain was 4.6%, while in Example 7 the strength was 1416.0 N and the weight gain was 7.2%. While both examples met the strength requirements of military fabrics for training uniforms, the weight gain of Comparative Example 5 was less than that of Example 7. This is because, unlike Example 7, Comparative Example 5 was not treated with lipase solution soaking, and the ultraviolet crosslinking treatment lacked specificity, making it difficult to break the ester bonds in the polyester molecular chain in a large number and in a directional manner. This resulted in a limited increase in the number of active groups on the fiber surface, making it difficult to combine with a large number of wear-resistant slow-release microcapsules or citric acid.

[0188] Comparative Example 6

[0189] The application of a wear-resistant sustained-release microcapsule is basically the same as in Example 7, except that the soaking time of the lipase solution in step (1) is 8 hours, and no ultraviolet crosslinking treatment is performed.

[0190] Compared to Example 7, the strength of the training uniform fabric in this case was 1443.8 N, with a weight gain of 5.0%, while in Example 7 the strength was 1416.0 N and the weight gain was 7.2%. While both examples met the strength requirements of military fabrics for training uniforms, the weight gain of Comparative Example 6 was lower than that of Example 7. This is because, compared to Example 7, Comparative Example 5 did not undergo UV crosslinking treatment. UV crosslinking treatment can make the fiber surface rougher, increase the specific surface area, expose more ester bonds that can interact with enzymes, and at the same time, to a certain extent, destroy the crystalline region of the fiber, allowing the enzyme to penetrate deeper into the fiber. The lack of UV crosslinking treatment will significantly reduce the effective action sites of the enzyme, preventing the enzyme molecules from fully contacting potential reaction sites. Therefore, the efficiency of Comparative Example 6 is lower than that of Example 7.

[0191] Example 8

[0192] An application of abrasion-resistant sustained-release microcapsules involves applying the abrasion-resistant sustained-release microcapsules from Example 2 onto a fabric via a padding method to obtain a highly abrasion-resistant and antifungal fabric. The specific steps are as follows:

[0193] (1) Clean the polyester-containing fabric, air dry it naturally, and then treat it in an ultraviolet crosslinker with an ultraviolet wavelength of 254nm and an energy of 90J for 0.5h. After that, soak it in a lipase solution with a concentration of 1g / L and let it stand at 25℃ for 9h.

[0194] (2) A finishing solution is obtained by mixing abrasion-resistant slow-release microcapsules, citric acid and ultrapure water, and the fabric obtained in step (1) is treated by two dips and two nips, and then baked to obtain a high abrasion-resistant and antifungal fabric; wherein, the content of abrasion-resistant slow-release microcapsules in the finishing solution is 20g / L, the content of citric acid is 20g / L, the bath ratio is 1:20, the baking temperature is 110℃, and the baking time is 5min.

[0195] The final high-abrasion-resistant antifungal fabric exhibited an inhibition rate of 85.70% against Candida albicans and 83.05% against Trichophyton rubrum. After being placed at 37°C for 30 days, the release rate of antibacterial essential oil from the abrasion-resistant sustained-release microcapsules was 34.7%. After 50 cycles of friction under a load of 260g, the release rate was 17.32%. After 50 cycles of friction under a load of 595g, the release rate was 19.21%. After 50 cycles of friction under a load of 795g, the release rate was 22.03%. After 50 cycles of friction under a load of 795g, the high-abrasion-resistant antifungal fabric showed an inhibition rate of 70.18% against Candida albicans and 69.89% against Trichophyton rubrum.

[0196] Example 9

[0197] An application of abrasion-resistant sustained-release microcapsules involves applying the abrasion-resistant sustained-release microcapsules from Example 3 to a fabric via padding to obtain a highly abrasion-resistant and antifungal fabric. The specific steps are as follows:

[0198] (1) Clean the polyester-containing fabric, air dry it naturally, and then treat it in an ultraviolet crosslinker with an ultraviolet wavelength of 254nm and an energy of 90J for 1.5h. After that, soak it in a lipase solution with a concentration of 2g / L and let it stand at 35℃ for 5h.

[0199] (2) A finishing solution is obtained by mixing abrasion-resistant slow-release microcapsules, citric acid and ultrapure water, and the fabric obtained in step (1) is treated by two dips and two nips, and then baked to obtain a high abrasion-resistant and antifungal fabric; wherein, the content of abrasion-resistant slow-release microcapsules in the finishing solution is 30 g / L, the content of citric acid is 30 g / L, the bath ratio is 1:30, the baking temperature is 120℃, and the baking time is 4 min.

[0200] The final high-abrasion-resistant antifungal fabric exhibited an inhibition rate of 88.12% against Candida albicans and 86.03% against Trichophyton rubrum. After being placed at 37°C for 30 days, the release rate of antibacterial essential oil from the abrasion-resistant sustained-release microcapsules was 35%. After 50 rubs under a load of 260g, the release rate was 18.01%. After 50 rubs under a load of 595g, the release rate was 20.28%. After 50 rubs under a load of 795g, the release rate was 23.05%. After 50 rubs under a load of 795g, the high-abrasion-resistant antifungal fabric showed an inhibition rate of 72.84% against Candida albicans and 71.50% against Trichophyton rubrum.

[0201] Example 10

[0202] An application of abrasion-resistant sustained-release microcapsules involves applying the abrasion-resistant sustained-release microcapsules from Example 4 onto a fabric via a padding method to obtain a highly abrasion-resistant and antifungal fabric. The specific steps are as follows:

[0203] (1) Clean the polyester-containing fabric, air dry it naturally, and then treat it in an ultraviolet crosslinker with an ultraviolet wavelength of 254nm and an energy of 90J for 3 hours. After that, soak it in a lipase solution with a concentration of 4g / L and let it stand at 40℃ for 3 hours.

[0204] (2) A finishing solution is obtained by mixing abrasion-resistant slow-release microcapsules, citric acid and ultrapure water, and the fabric obtained in step (1) is treated by two dips and two nips, and then baked to obtain a high abrasion-resistant and antifungal fabric; wherein, the content of abrasion-resistant slow-release microcapsules in the finishing solution is 40 g / L, the content of citric acid is 40 g / L, the bath ratio is 1:40, the baking temperature is 130℃, and the baking time is 3 min.

[0205] The final high-abrasion-resistant antifungal fabric exhibited an inhibition rate of 90.52% against Candida albicans and 90.03% against Trichophyton rubrum. After being placed at 37°C for 30 days, the release rate of antibacterial essential oil from the abrasion-resistant sustained-release microcapsules was 35.84%. After 50 cycles of friction under a load of 260g, the release rate was 19.07%. After 50 cycles of friction under a load of 595g, the release rate was 21.09%. After 50 cycles of friction under a load of 795g, the release rate was 24.55%. After 50 cycles of friction under a load of 795g, the high-abrasion-resistant antifungal fabric showed an inhibition rate of 74.01% against Candida albicans and 73.02% against Trichophyton rubrum.

[0206] Example 11

[0207] An application of abrasion-resistant sustained-release microcapsules involves applying the abrasion-resistant sustained-release microcapsules from Example 5 onto a fabric via a padding method to obtain a highly abrasion-resistant and antifungal fabric. The specific steps are as follows:

[0208] (1) Clean the polyester-containing fabric, air dry it naturally, and then treat it in an ultraviolet crosslinker with an ultraviolet wavelength of 254nm and an energy of 90J for 6 hours. After that, soak it in a lipase solution with a concentration of 8g / L and let it stand at 50℃ for 1 hour.

[0209] (2) A finishing solution is obtained by mixing abrasion-resistant slow-release microcapsules, citric acid and ultrapure water, and the fabric obtained in step (1) is treated by two dips and two nips, and then baked to obtain a high abrasion-resistant and antifungal fabric; wherein, the content of abrasion-resistant slow-release microcapsules in the finishing solution is 50 g / L, the content of citric acid is 50 g / L, the bath ratio is 1:50, the baking temperature is 140℃, and the baking time is 2 min.

[0210] The final high-abrasion-resistant antifungal fabric exhibited an inhibition rate of 94.10% against Candida albicans and 93.03% against Trichophyton rubrum. After being placed at 37℃ for 30 days, the release rate of antibacterial essential oil from the abrasion-resistant sustained-release microcapsules was 36.2%. After 50 cycles of friction under a load of 260g, the release rate was 21.2%. After 50 cycles of friction under a load of 595g, the release rate was 23.46%. After 50 cycles of friction under a load of 795g, the release rate was 26.98%. After 50 cycles of friction under a load of 795g, the high-abrasion-resistant antifungal fabric showed an inhibition rate of 75.83% against Candida albicans and 75.08% against Trichophyton rubrum.

[0211] Example 12

[0212] An application of abrasion-resistant sustained-release microcapsules involves applying the abrasion-resistant sustained-release microcapsules from Example 6 to a fabric via padding to obtain a highly abrasion-resistant and antifungal fabric. The specific steps are as follows:

[0213] (1) Clean the polyester-containing fabric, air dry it naturally, and then treat it in an ultraviolet crosslinker with an ultraviolet wavelength of 254nm and an energy of 90J for 9 hours. After that, soak it in a lipase solution with a concentration of 10g / L and let it stand at 60℃ for 0.5 hours.

[0214] (2) A finishing solution is obtained by mixing abrasion-resistant slow-release microcapsules, citric acid and ultrapure water, and the fabric obtained in step (1) is treated by two dips and two nips, and then baked to obtain a high abrasion-resistant and antifungal fabric; wherein, the content of abrasion-resistant slow-release microcapsules in the finishing solution is 60 g / L, the content of citric acid is 60 g / L, the bath ratio is 1:60, the baking temperature is 150℃, and the baking time is 1 min.

[0215] The final high-abrasion-resistant antifungal fabric exhibited an inhibition rate of 95.74% against Candida albicans and 95.10% against Trichophyton rubrum. After being placed at 37°C for 30 days, the release rate of antibacterial essential oil from the abrasion-resistant sustained-release microcapsules was 37.04%. After 50 cycles of friction under a load of 260g, the release rate was 22.82%. After 50 cycles of friction under a load of 595g, the release rate was 24.09%. After 50 cycles of friction under a load of 795g, the release rate was 27.87%. After 50 cycles of friction under a load of 795g, the high-abrasion-resistant antifungal fabric showed an inhibition rate of 77.83% against Candida albicans and 76.33% against Trichophyton rubrum.

Claims

1. A wear-resistant sustained-release microcapsule, characterized in that, It has a core-shell structure, with the shell consisting of an inner shell and an outer shell; the core layer is an antibacterial essential oil, the inner shell is an organic material layer with water-swelling properties, and the outer shell is a silica layer.

2. The wear-resistant sustained-release microcapsule according to claim 1, characterized in that, The antibacterial essential oils are Cnidium monnieri essential oil and / or Sophora flavescens essential oil.

3. The wear-resistant sustained-release microcapsule according to claim 1, characterized in that, The organic material layer with water-swelling properties is a network structure formed by chitosan, gum arabic, and glutaraldehyde; chitosan and gum arabic are connected by ionic bonds, while glutaraldehyde and chitosan are connected by covalent bonds.

4. The wear-resistant sustained-release microcapsule according to claim 1, characterized in that, The core layer has a diameter of 0.62~1.35μm, the inner shell layer has a thickness of 0.31~1.34μm, and the outer shell layer has a thickness of 0.28~0.81μm.

5. A method for preparing a wear-resistant sustained-release microcapsule as described in any one of claims 1 to 4, characterized in that, When the antibacterial essential oil is in the form of emulsion droplets, an intermediate product is obtained by coating the surface of the antibacterial essential oil with an organic material that has water-swelling properties through a complex coagulation method. Then, silica is coated on the surface of the intermediate product by a tetraethyl orthosilicate hydrolysis method to obtain wear-resistant sustained-release microcapsules.

6. The method according to claim 5, characterized in that, The steps for coating the surface of antibacterial essential oils with an organic material that swells upon contact with water are as follows: (a) Under the condition of heating in a water bath to 30~60℃, add gum arabic to water to prepare gum arabic aqueous solution, then maintain the water bath heating temperature, add antibacterial essential oil and emulsifier to gum arabic aqueous solution, stir at 5000~15000rpm for 1~10min, and then add chitosan glacial acetic acid solution at 5000~15000rpm at a dropping rate of 1~2mL / min to obtain a mixture; (b) Continue to maintain the water bath heating temperature of step (a), adjust the pH of the mixture to 4.0~6.0 with pH adjuster A, and react for 15~120 min. Then, cool the mixture to 0~10℃, and adjust the pH of the mixture to above 7 with pH adjuster A during the cooling process. Then, add glutaraldehyde aqueous solution to the mixture dropwise at a speed of 1~2 mL / min at a speed of 300~500 rpm to obtain the intermediate product.

7. The method according to claim 6, characterized in that, The mass ratio of antibacterial essential oil to the total mass of gum arabic and chitosan is 1:0.67 to 1:1.5; the mass ratio of chitosan to gum arabic is 1:1 to 1:7; the mass of emulsifier is 0.5 to 10% of the mass of antibacterial essential oil; and the mass of glutaraldehyde is 2.5 to 5% of the total mass of chitosan and gum arabic.

8. The method according to claim 5, characterized in that, The specific process of coating the intermediate product with silica is as follows: after dispersing the intermediate product in ultrapure water, tetraethyl orthosilicate is added dropwise at a rate of 1-2 mL / min while stirring at 300-500 rpm. Then, the pH of the system is adjusted to 2-3 using pH adjuster B. After stirring at 300-500 rpm for 36-48 h at 30-40℃, wear-resistant sustained-release microcapsules are obtained. The mass-volume ratio of the intermediate product to tetraethyl orthosilicate is 1 g: 2-6 mL.

9. The application of the wear-resistant sustained-release microcapsule as described in any one of claims 1 to 4, characterized in that, Abrasion-resistant, slow-release microcapsules are applied to fabrics using a padding method to produce highly abrasion-resistant and antifungal fabrics.

10. The application according to claim 9, characterized in that, The specific preparation steps for high abrasion-resistant and antifungal fabric are as follows: (1) Place the polyester-containing fabric in an ultraviolet crosslinker with an ultraviolet light wavelength of 254nm and an energy of 90J for 0.5~9h, then soak it in lipase solution and let it stand at 25~60℃ for 0.5~9h; (2) A finishing solution is obtained by mixing abrasion-resistant slow-release microcapsules, citric acid and ultrapure water, and the fabric obtained in step (1) is treated by two dips and two nips, and then baked to obtain a high abrasion-resistant and antifungal fabric; wherein, in the finishing solution, the content of abrasion-resistant slow-release microcapsules is 20~60g / L, the content of citric acid is 20~60g / L, the bath ratio is 1:10~40, the baking temperature is 110~150℃, and the baking time is 1~5min.

Images