Preparation method of antibacterial and antiviral degradable bacterial grass fiber blended yarn material

Abstract

The application relates to the field of functional textile yarn preparation technology and discloses a preparation method of an antibacterial and antiviral degradable bacteria grass fiber blended yarn material, which comprises the following steps: sequentially performing alkali treatment, bleaching, oxygen removal, enzymatic hydrolysis softening, drying and opening treatment on short pieces of naturally dried giant bacteria grass to obtain unmodified spinnable bacteria grass fiber; immersing and padding the unmodified spinnable bacteria grass fiber in a composite working solution containing citric acid, sodium hypophosphite, quaternary ammonium chitosan, tannic acid, nano zinc oxide, polyethylene glycol and glycerol, then performing pre-drying and baking; performing closed steam moisturizing forced residence treatment on the bacteria grass fiber after the baking treatment, and cooling to obtain modified bacteria grass fiber; and mixing the modified bacteria grass fiber with raw cotton fiber and polylactic acid fiber, and performing a spinning process to obtain the blended yarn material. In the application, sodium hypophosphite is used as a catalyst and plays a certain reduction role, citric acid is used as a crosslinking agent, functional components form a stable combination structure, and the stability of the antibacterial and antiviral functions is improved.

Description

Technical Field

[0001] This invention relates to the field of functional textile yarn preparation technology, specifically a method for preparing an antibacterial and antiviral biodegradable fungal and grass fiber blended yarn material. Background Technology

[0002] With the increasing demand for daily hygiene and protection, textiles with antibacterial and antiviral functions are being used in clothing, home textiles, and public health products. Natural plant fibers, characterized by their skin-friendliness, breathability, and biodegradability, have application value in the field of green textile materials. Giant Napier grass is widely available and has a high biomass; after pretreatment, it can yield Napier grass fibers with a certain length and spinnability. Blending these fibers with raw cotton, polylactic acid fibers, and other materials can be used to prepare textile yarns that are both functional and biodegradable.

[0003] Existing antibacterial finishing processes for plant fibers typically employ impregnation, padding, or coating methods to load inorganic antibacterial agents, quaternary ammonium salt antibacterial agents, or plant polyphenol functional components onto the fiber surface. These processes are relatively simple, require minimal modification to existing spinning equipment, and the finished fibers can achieve a certain initial antibacterial effect.

[0004] However, relying solely on physical adsorption or surface adhesion methods results in insufficient bonding strength between functional components and plant fibers, leading to easy loss during subsequent washing and a reduced retention rate of antibacterial and antiviral functions. To improve the wash resistance of functional components, existing technologies also employ crosslinking agents or high-temperature baking processes to enhance their fixation on the fibers. However, in composite working solutions containing quaternary ammonium compounds, polyphenols, and inorganic nanoparticles, different functional components are prone to aggregation or sedimentation, affecting the uniformity of the padding process. Simultaneously, polyphenols are prone to oxidative browning during high-temperature baking, affecting the appearance and color of the modified fibers. Furthermore, after high-temperature baking and crosslinking treatment, the moisture content of plant fibers decreases, restricting fiber chain movement and easily leading to a decrease in fiber flexibility. For Juncao fiber, it needs to withstand carding, drafting, and twisting during subsequent mechanical processing such as carding, drawing, roving, and spinning. If the modified fiber strength and elongation are insufficient, it can easily lead to increased carding waste, increased short fibers, and decreased yarn evenness and strength. Therefore, existing technologies still require a method for preparing Juncao fiber blended yarn that can balance the wash resistance retention of functional components, working solution stability, modified fiber flexibility, and blended yarn processing adaptability. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method for preparing a biodegradable blended yarn material of antibacterial and antiviral fungi and grass fibers. This method solves the problems of insufficient wash resistance of functional components, poor stability of composite working solutions, easy embrittlement of fibers after high-temperature crosslinking, and insufficient adaptability of modified fibers to spinning and processing in existing antibacterial and antiviral finishing of plant fibers.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A method for preparing an antibacterial and antiviral biodegradable spunbond fiber blended yarn material includes the following steps: S1. Naturally dried short sections of giant reed grass are subjected to alkali treatment, bleaching, deoxygenation, enzymatic softening, drying and opening treatment in sequence to obtain unmodified spinnable reed grass fiber. S2. The unmodified spinnable Juncao fiber is impregnated in the composite working solution, and then pre-dried and baked to obtain baked Juncao fiber; the composite working solution contains citric acid, sodium hypophosphite, quaternized chitosan, tannic acid, nano zinc oxide, polyethylene glycol and glycerin. S3. The baked Juncao fiber is subjected to closed steam humidification forced retention treatment, and after cooling, modified Juncao fiber is obtained. S4. The modified Juncao fiber is mixed with raw cotton fiber and polylactic acid fiber, and the antibacterial and antiviral biodegradable Juncao fiber blended yarn material is obtained through a spinning process.

[0007] By adopting the above technical solution, the present invention connects the pretreatment of Juncao fiber, fixation of functional components, post-baking humidification control and subsequent blending and spinning processes, so that Juncao fiber can obtain antibacterial and antiviral functions while maintaining a fiber state suitable for subsequent mechanical spinning processing.

[0008] Specifically, in the functional cross-linking process, the macromolecules of Juncao fiber contain hydroxyl groups on their surface, quaternized chitosan contains hydroxyl and amino groups, and tannic acid contains polyphenolic hydroxyl groups. Under baking conditions, sodium hypophosphite acts as a catalyst, and citric acid acts as a multifunctional cross-linking agent, participating in the esterification or amidation reactions between these groups. Citric acid undergoes dehydration and activation under heating conditions, forming an anhydride-based active intermediate. This anhydride-based active intermediate can undergo esterification with the hydroxyl groups on the Juncao cellulose molecular chain, forming an ester-bonded structure on the fiber surface and in the amorphous region of the fiber. Simultaneously, the unreacted carboxyl groups in the citric acid molecule can continue to undergo condensation reactions with the hydroxyl and amino groups in the quaternized chitosan molecule and the polyphenolic hydroxyl groups in the tannic acid, thereby forming a multi-component solid-phase cross-linked structure. Nano-zinc oxide is confined within this cross-linked structure through dispersion, complexation, or encapsulation, improving the fixation stability of the functional components on the Juncao fiber.

[0009] The aforementioned cross-linked structure facilitates the fixation of cationic antibacterial components, polyphenolic antiviral components, and nano-zinc oxide onto the Juncao fiber, thereby improving the retention of functional components after washing. Simultaneously, sodium hypophosphite possesses certain reducing properties, which, under high-temperature aerobic baking conditions, helps reduce the degree of oxidative browning of the tannic acid polyphenol structure, thus improving the color stability of the modified fiber.

[0010] Regarding the stability of the working solution and the enhancement of fiber flexibility, the composite working solution contains quaternized chitosan, tannic acid, and nano-zinc oxide. Quaternized chitosan contains cationic groups, tannic acid contains polyphenolic hydroxyl groups, and nano-zinc oxide is easily affected by its dispersion state in an aqueous system. Polyethylene glycol contains ether bonds and terminal hydroxyl groups, and glycerol contains polyhydroxy structures. Both can form multi-point interactions with water molecules and functional components, reducing the degree of aggregation between components, improving the dispersion stability of the composite working solution, and reducing the sedimentation rate of the effective components. During the pre-drying and baking stages, polyethylene glycol and glycerol can enter the pores and amorphous regions of the Juncao fiber, regulating the interactions between fiber segments, thereby reducing the impact of cross-linking treatment on fiber flexibility.

[0011] Regarding the fiber state after heat treatment, the Juncao fiber, after baking, is in a high-temperature, low-moisture state, and is prone to localized internal stress during heat treatment and cross-linking. Through closed-loop steam humidification and forced retention treatment, moisture enters the fiber capillaries and amorphous regions, plasticizing the fiber macromolecular segments. This facilitates the transition of the fiber from a high-temperature, low-moisture state to a balanced rehydration state and promotes the release of internal stress after heat treatment. This process helps improve the breaking elongation and breaking strength of individual fibers.

[0012] Based on the combined effects of chemical fixation and physical regulation, the modified Juncao fiber retains good machinability while acquiring antibacterial and antiviral functions. During subsequent blending and mechanical carding processes, fiber breakage is reduced, which helps control cotton waste and short fiber increase rate, and provides conditions for preparing blended yarns with uniform yarn evenness and stable strength.

[0013] Preferably, the composite working fluid is prepared by mixing the following components in parts by weight: 1000 parts water; 10 to 30 parts citric acid; 5 to 15 parts sodium hypophosphite; 2 to 20 parts tannic acid; 5 to 30 parts quaternized chitosan; 1 to 15 parts nano zinc oxide; 10 to 20 parts polyethylene glycol; and 3 to 10 parts glycerol.

[0014] By adopting the above technical solution, the components are combined in a set ratio to form a composite finishing system. The combined use of citric acid and sodium hypophosphite is beneficial for promoting esterification and crosslinking under conventional baking conditions; the combined use of tannic acid, quaternized chitosan, and nano zinc oxide is beneficial for improving the antibacterial and antiviral properties of the yarn; the addition of polyethylene glycol and glycerin is beneficial for improving the dispersion stability of the working solution and reducing the impact of crosslinking treatment on fiber flexibility.

[0015] Preferably, each raw material component satisfies the following characteristic parameters: the average particle size of the nano zinc oxide is 30 to 50 nanometers; the polyethylene glycol is PEG-400 with an average molecular weight of 380 to 420; the length of the naturally dried short segments of giant reed grass is 30 to 80 millimeters; the length of the unmodified spinnable reed grass fiber is 25 to 45 millimeters; the length of the raw cotton fiber is 27 to 31 millimeters; and the fineness of the polylactic acid fiber is 1.2 to 1.5D, with a weight-average molecular weight of 100,000 to 150,000.

[0016] By adopting the above technical solutions, nano zinc oxide has a high specific surface area, which is beneficial to improving its efficiency on the fiber surface; PEG-400 has good water solubility and fluidity, which is convenient to disperse in the working solution and penetrate into the fiber pores; the length and fineness parameters of giant reed fiber, raw cotton fiber and polylactic acid fiber are matched with each other, which is beneficial to improve the motion consistency of multi-component fibers in the mixing, carding and drafting process, thereby reducing yarn evenness fluctuation.

[0017] Preferably, the degree of quaternization substitution of the quaternized chitosan is 42% to 78%.

[0018] By employing the above technical solution, when the degree of quaternization substitution is controlled within the aforementioned range, quaternized chitosan exhibits good water solubility and cationic group content, while retaining a certain number of amino and hydroxyl groups. These amino and hydroxyl groups can serve as cross-linking reaction sites, participating in esterification or amidation reactions with citric acid, thereby improving the binding stability of quaternized chitosan on Juncao fiber.

[0019] Preferably, the method for preparing the quaternized chitosan includes the following steps: (1) Disperse chitosan in an aqueous acetic acid solution, heat to 60 to 70 degrees Celsius and stir until completely dissolved to obtain a chitosan acetic acid solution; (2) Add 19 to 57 parts by weight of 3-chloro-2-hydroxypropyltrimethylammonium chloride aqueous solution to the system according to the ratio of 10 parts by weight of chitosan. Then add sodium hydroxide aqueous solution to adjust the pH of the system to 8.0 to 9.0. Recycle under closed reflux at a constant temperature of 70 to 85 degrees Celsius for 8 to 12 hours. (3) After the reaction is completed, cool to room temperature, precipitate in anhydrous acetone, collect the precipitate and redissolve it in deionized water, dialyze it with a dialysis bag for 3 to 5 days, and freeze dry to obtain quaternized chitosan.

[0020] By employing the above technical solution, 3-chloro-2-hydroxypropyltrimethylammonium chloride can form a reactive epoxidation intermediate in a weakly alkaline environment. The amino and hydroxyl groups on the chitosan molecular chain can undergo a ring-opening grafting reaction with this intermediate, thereby introducing a quaternary ammonium salt structure into the chitosan backbone. By limiting the system pH to 8.0 to 9.0 and controlling the reflux temperature, the grafting reaction efficiency can be improved, and the adverse effects of strongly alkaline conditions on the chitosan backbone can be reduced.

[0021] Preferably, in step S1, the alkali treatment uses a sodium hydroxide aqueous solution with a mass concentration of 2% to 8% and is treated at 95 to 100 degrees Celsius for 45 to 60 minutes; the bleaching uses a hydrogen peroxide aqueous solution with a mass concentration of 2% to 4% and is treated at 70 to 80 degrees Celsius for 40 to 60 minutes; the deoxygenation uses catalase, wherein the enzyme activity of the catalase is greater than or equal to 50,000 U / g; and the enzymatic hydrolysis softening uses cellulase and xylanase, wherein the enzyme activity of the cellulase is greater than or equal to 10,000 U / g and the enzyme activity of the xylanase is greater than or equal to 50,000 U / g.

[0022] By employing the above technical solutions, alkali treatment can remove some lignin, hemicellulose, and impurities from giant reed grass, while bleaching treatment can reduce the impact of residual pigments on the fiber appearance. Catalase treatment is used to decompose residual hydrogen peroxide after bleaching, reducing its impact on subsequent enzymatic hydrolysis steps. The combined use of cellulase and xylanase can regulate the inter-fiber bundle binding structure, promote fiber bundle dispersion and softening, and improve the uniformity of subsequent padding modification.

[0023] Preferably, step S2 is implemented as follows: the unmodified spinnable fungus fiber is immersed in the composite working solution for 15 to 30 minutes and then rolled to control the roll residue rate to 70% to 80%; then pre-drying is carried out at 70 to 80 degrees Celsius, and the moisture regain rate of the fiber after pre-drying is controlled to be 8% to 12%; and then baking is carried out at 130 to 140 degrees Celsius for 3 to 5 minutes.

[0024] By adopting the above technical solutions, controlling the roll-off rate is beneficial to ensure that the composite working solution is uniformly loaded in the Juncao fiber; the pre-drying treatment is used to remove some free water and reduce the migration of solutes on the fiber surface before high-temperature baking; the baking treatment provides thermal conditions for the citric acid crosslinking reaction, which is beneficial to the formation of a more stable fixed structure of functional components on the fiber surface and in the fiber pores.

[0025] Preferably, step S3 is implemented as follows: the roasted mushroom fiber is introduced into a closed steam humidification chamber while it is still hot, the ambient temperature inside the closed steam humidification chamber is controlled at 40 to 50 degrees Celsius and the relative humidity is 85% to 95%, and the forced residence treatment is carried out for 10 to 15 minutes, and then cooled to room temperature.

[0026] By adopting the above technical solution, the baked fibers are in a high-temperature, low-moisture state. Timely closed-loop steam humidification treatment facilitates the entry of moisture into the fiber pores and amorphous regions, thereby reducing the rigidity of the fibers after heat treatment and promoting the release of internal stress. This treatment is beneficial for improving the breaking elongation and subsequent carding adaptability of the modified Juncao fiber.

[0027] Preferably, in step S4, the composition of each fiber in the blended yarn material by weight percentage is as follows: 30% to 50% modified hygroscopic fiber; 35% to 55% raw cotton fiber; 10% to 15% polylactic acid fiber; the sum of the weight percentages of the above components is 100%.

[0028] By adopting the above technical solutions, modified Juncao fiber provides antibacterial and antiviral functions, raw cotton fiber improves the moisture absorption and spinning cohesion of blended yarn, and polylactic acid fiber increases the proportion of biodegradable fiber components in the yarn and provides a certain degree of support for the yarn. The combination of these three fibers in the above proportions is beneficial for balancing functionality, biodegradability, and yarn processing performance.

[0029] Preferably, in step S4, the spinning process sequentially includes opening and cleaning, carding, drawing, roving, spinning, winding, and twisting; wherein, in the carding process, the cylinder speed is 280 to 380 revolutions per minute, the doffer speed is 15 to 30 revolutions per minute, and the flats speed is 100 to 140 millimeters per minute; the roving twist coefficient is 80 to 120, the spinning twist coefficient is 330 to 420, and 10 to 60 count blended yarn is spun.

[0030] By adopting the above technical solutions, controlling the speed of the cylinder, doffer, and flats in the carding process helps to reduce mechanical damage to the straw fibers during the carding process; controlling the twist coefficient of the roving and yarn helps to improve the cohesion between heterogeneous fibers and improve the evenness and breaking strength of the blended yarn.

[0031] This invention provides a method for preparing an antibacterial and antiviral biodegradable spunbond fiber blended yarn material. It has the following beneficial effects: 1. This invention uses sodium hypophosphite as a catalytic reducing agent and citric acid as a crosslinking agent. Under baking conditions, a bond structure containing ester or amide bonds is formed between the Juncao fiber, quaternized chitosan, and tannic acid. This also fixes nano-zinc oxide onto the fiber surface and within the fiber pores, which is beneficial for improving the binding stability of cationic antibacterial components, polyphenolic antiviral components, and nano-zinc oxide on the fiber, thereby improving the retention rate of antibacterial and antiviral functions of the blended yarn after multiple washes. Simultaneously, sodium hypophosphite helps reduce the degree of oxidative browning of the tannic acid polyphenol structure during baking, improving the color stability of the modified Juncao fiber. 2. This invention utilizes polyethylene glycol and glycerol in the composite working solution. Polyethylene glycol and glycerol can form multi-point interactions with quaternized chitosan, tannic acid, nano-zinc oxide, and water molecules, reducing the aggregation degree between functional components, improving the dispersion stability of the composite working solution, and reducing the sedimentation rate of the effective components. During pre-drying and baking, polyethylene glycol and glycerol can penetrate the pores and amorphous regions of the Juncao fiber, regulating the interactions between fiber segments, thereby reducing the impact of crosslinking treatment on fiber flexibility and maintaining the mechanical properties of the modified Juncao fiber suitable for subsequent carding and spinning processes. 3. This invention applies a closed-loop steam humidification forced retention treatment to the roasted Juncao fiber, allowing moisture to enter the internal pores and amorphous regions of the fiber in a high-temperature, low-moisture state. This promotes the transition of the fiber from a high-temperature, low-moisture state to a balanced rehydration state and helps release the localized internal stress formed after the roasting treatment. This improves the breaking elongation and breaking strength of the modified Juncao fiber. At the same time, combined with the control of the blending ratio and carding process parameters, it helps to reduce the cotton waste rate and short fiber increase rate during mechanical carding, and improves the evenness and breaking strength of the blended yarn. Attached Figure Description

[0032] Figure 1 The image shows a comparison of the infrared spectra of unmodified spinnable Juncao fiber and modified Juncao fiber from Example 1. Detailed Implementation

[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] The main raw materials and reagents used in the following examples and comparative examples are as follows. Unless otherwise stated, all chemical reagents are commercially available analytical grade or higher products, and all fiber raw materials are commercially available industrial products.

[0035] (1) Juncao raw material: short sections of naturally dried giant Juncao harvested in industry, which are physically cut and have a length of 30-80mm; (2) Raw cotton fiber: Natural cotton fiber that has not undergone chemical modification, with a length of 27-31 mm; (3) Polylactic acid fiber: Polylactic acid fiber, also known as polylactide fiber, is a linear aliphatic polyester polymer compound formed by ring-opening polymerization of lactide. Its CAS number is 26100-51-6, its weight-average molecular weight is 100,000-150,000, its spinning fineness is 1.2-1.5D, and its cutting length is 38mm. (4) Chitosan: Deacetylated chitin, CAS number 9012-76-4, degree of deacetylation ≥85%, weight average molecular weight 100,000-300,000; (5) 3-Chloro-2-hydroxypropyltrimethylammonium chloride: CAS number 3327-22-8, in the form of a 60% aqueous solution; (6) Nano zinc oxide: CAS number 1314-13-2, average particle size 30-50nm, purity ≥99%; (7) Polyethylene glycol: PEG-400, a polyether compound formed by the polymerization of ethylene oxide, with ether bonds and terminal hydroxyl groups in its molecular structure, CAS number 25322-68-3, and average molecular weight of 380-420; (8) Cellulase: CAS No. 9012-54-8, in the form of solid powder, enzyme activity ≥10000U / g; (9) Xylanase: CAS No. 9025-57-4, in the form of solid powder, enzyme activity ≥50000U / g; (10) Catalase: CAS number 9001-05-2, in the form of solid powder, enzyme activity ≥50000U / g.

[0036] Preparation Example 1: This preparation example provides a method for preparing quaternized chitosan, including the following steps: (1) Disperse 10.0g of chitosan powder in 490g of 1% acetic acid aqueous solution, heat the system to 65℃ and stir continuously for 2h to completely dissolve it, and obtain chitosan acetic acid solution; (2) Slowly add 38.0 g of 60% 3-chloro-2-hydroxypropyltrimethylammonium chloride aqueous solution to the system, controlling the addition time to 30 min. After the addition is completed, slowly add 10% sodium hydroxide aqueous solution to adjust the pH of the system to 8.5. Recycle in a closed reflux reaction at 80℃ for 10 h. (3) After the reaction was completed, the mixture was cooled to room temperature and slowly poured into 2000 mL of anhydrous acetone for precipitation. The slightly yellow flocculent precipitate was collected by filtration. The precipitate was redissolved in 500 mL of deionized water, placed in a dialysis bag with a molecular weight cutoff of 3500 Da, and dialyzed with deionized water for 4 days. After freeze-drying, quaternized chitosan solid powder was obtained. The degree of quaternization was determined to be 60% by potentiometric titration.

[0037] Preparation Example 2: This preparation example provides a method for preparing quaternized chitosan, including the following steps: (1) Disperse 10.0g of chitosan powder in 490g of 1% acetic acid aqueous solution, heat the system to 60℃ and stir continuously for 2h to completely dissolve it, and obtain chitosan acetic acid solution; (2) Slowly add 19.0 g of 60% 3-chloro-2-hydroxypropyltrimethylammonium chloride aqueous solution to the system, controlling the addition time to 30 min. After the addition is completed, slowly add 10% sodium hydroxide aqueous solution to adjust the pH of the system to 8.0. Then, reflux the reaction under a closed water bath at 70℃ for 8 h. (3) After the reaction, the mixture was cooled to room temperature and slowly poured into 2000 mL of anhydrous acetone for precipitation. The slightly yellow flocculent precipitate was collected by filtration. The precipitate was redissolved in 500 mL of deionized water, placed in a dialysis bag with a molecular weight cutoff of 3500 Da, and dialyzed with deionized water for 3 days. After freeze-drying, quaternized chitosan solid powder was obtained. The degree of quaternization was determined to be 42% by potentiometric titration.

[0038] Preparation Example 3: This preparation example provides a method for preparing quaternized chitosan, including the following steps: (1) Disperse 10.0g of chitosan powder in 490g of 1% acetic acid aqueous solution, heat the system to 70℃ and stir continuously for 2h to completely dissolve it, and obtain chitosan acetic acid solution; (2) Slowly add 57.0 g of 60% 3-chloro-2-hydroxypropyltrimethylammonium chloride aqueous solution to the system, controlling the addition time to 30 min. After the addition is completed, slowly add 10% sodium hydroxide aqueous solution to adjust the pH of the system to 9.0. Then, reflux the reaction in a closed water bath at 85℃ for 12 h. (3) After the reaction, the mixture was cooled to room temperature and slowly poured into 2000 mL of anhydrous acetone for precipitation. The slightly yellow flocculent precipitate was collected by filtration. The precipitate was redissolved in 500 mL of deionized water, placed in a dialysis bag with a molecular weight cutoff of 3500 Da, and dialyzed with deionized water for 5 days. After freeze-drying, quaternized chitosan solid powder was obtained. The degree of quaternization was determined to be 78% by potentiometric titration.

[0039] Example 1: This example provides a method for preparing an antibacterial and antiviral biodegradable fungal grass fiber blended yarn material, including the following steps: (1) Cut 10.0 kg of Juncao raw material into short segments with a length of 30-80 mm, put them into a reaction vessel, add 150 L of sodium hydroxide aqueous solution with a mass concentration of 5%, keep it at 98℃ for 50 min, and then wash it with water until neutral; add 150 L of hydrogen peroxide aqueous solution with a mass concentration of 3%, and bleach it at 75℃ for 50 min; after draining the liquid, replace it with 150 L of water, add 45.0 g of catalase, and treat it at 45℃ for 18 min to remove residual hydrogen peroxide; adjust the pH of the bath liquid to 4.8, add 200.0 g of compound enzyme preparation (composed of 120.0 g of cellulase and 80.0 g of xylanase), treat it at 50℃ for 40 min, and then raise the temperature to 85℃ to inactivate it; wash the treated fiber thoroughly with water, centrifuge to dehydrate, dry it at 65℃, and open it with a cotton opener to obtain spinnable Juncao fiber with a length of 25-45 mm; (2) Preparation of Solution A: Add 5L of deionized water to the mixing tank, then add 100.0g of tannic acid and 80.0g of nano zinc oxide sequentially. Stir at 400r / min for 40min at 45℃ to obtain a brownish-yellow sol. Preparation of Solution B: Add 5L of deionized water to another mixing tank with a cooling jacket, then add 150.0g of quaternized chitosan obtained in Preparation Example 1 and stir to dissolve. After complete dissolution, slowly add 200.0g of citric acid, 100.0g of sodium hypophosphite, 150.0g of polyethylene glycol and 60.0g of glycerol sequentially. Turn on the jacket cooling and control the solution temperature at 25℃. Under continuous stirring, pump Solution A into Solution B at a uniform rate to obtain a composite working solution. The pH of the composite working solution is 4.5, and the temperature is maintained at 25℃. (3) The spinnable Juncao fiber prepared in step (1) is continuously passed through the composite working liquid impregnation tank in the form of a mesh belt, the impregnation temperature is controlled at 25℃, the impregnation time is 20min, and the residual rate of the double roller water mill is controlled at 75%; the fiber is conveyed to the mesh belt pre-drying box and dried with hot air at 75℃, and the moisture regain of the fiber after exiting the box is controlled at 10%; the pre-dried fiber is continuously fed into the baking machine and baked at 135℃ for 4min; after the fiber exits the baking machine, it is immediately introduced into the closed steam humidification box while hot, the ambient temperature in the humidification box is set at 45℃, the relative humidity is set at 90%, and the forced residence treatment is performed for 12min, and then cooled to room temperature through the cold air trough to obtain modified Juncao fiber; (4) Weigh 40% modified Juncao fiber, 45% cotton fiber and 15% polylactic acid fiber by mass percentage. Before mixing, control the balance moisture regain of each component in an independent humidity conditioning room. The modified Juncao fiber is controlled at 10%, the cotton fiber at 7.5% and the polylactic acid fiber at 1.2%. After mixing, the mixture is opened and mixed in the opening and cleaning process, and then sent to the carding machine for carding. (5) The carding machine cylinder speed is set to 330 r / min, the doffer speed is set to 22 r / min, and the cover speed is set to 120 mm / min. The machine undergoes two drawing processes. In the roving process, the roving twist coefficient is controlled at 100. In the spinning process, ring spinning is used, and the spinning twist coefficient is controlled at 380 to produce 30-count blended bobbin yarn. (6) After the blended yarn obtained from the fine spinning process is wound into a winding tube, it is placed in a vacuum steaming box and treated under saturated steam at 70°C for 30 minutes to complete the twisting and obtain the finished blended yarn material.

[0040] Example 2: This example provides a method for preparing an antibacterial and antiviral biodegradable fungal grass fiber blended yarn material, including the following steps: (1) Cut 10.0 kg of Juncao raw material into short segments with a length of 30-80 mm, put them into a reaction vessel, add 150 L of sodium hydroxide aqueous solution with a mass concentration of 2%, keep it at 95℃ for 45 min, and then wash it with water until neutral; add 150 L of hydrogen peroxide aqueous solution with a mass concentration of 2%, and bleach it at 70℃ for 40 min; after draining the liquid, replace it with 150 L of water, add 15.0 g of catalase, and treat it at 40℃ for 15 min to remove residual hydrogen peroxide; adjust the pH of the bath liquid to 4.5, add 100.0 g of compound enzyme preparation (composed of 50.0 g of cellulase and 50.0 g of xylanase), treat it at 45℃ for 30 min, and then raise the temperature to 85℃ to inactivate it; wash the treated fiber thoroughly with water, centrifuge to dehydrate, dry it at 60℃, and open it with a cotton opener to obtain spinnable Juncao fiber with a length of 25-45 mm; (2) Preparation of Solution A: Add 5L of deionized water to the mixing tank, then add 20.0g of tannic acid and 10.0g of nano zinc oxide sequentially. Stir at 300r / min for 30min at 40℃ to obtain a brownish-yellow sol. Preparation of Solution B: Add 5L of deionized water to another mixing tank with a cooling jacket, then add 50.0g of quaternized chitosan obtained in Preparation Example 2 and stir to dissolve. After complete dissolution, slowly add 100.0g of citric acid, 50.0g of sodium hypophosphite, 100.0g of polyethylene glycol and 30.0g of glycerol sequentially. Turn on the jacket cooling and control the solution temperature at 20℃. Under continuous stirring, pump Solution A into Solution B at a uniform rate to obtain a composite working solution. The pH of the composite working solution is 4.8, and the temperature is maintained at 20℃. (3) The spinnable Juncao fiber prepared in step (1) is continuously passed through the composite working liquid impregnation tank in the form of a mesh belt, the impregnation temperature is controlled at 20℃, the impregnation time is 15min, and the residual rate of the double roller water mill is controlled at 70%; the fiber is conveyed to the mesh belt pre-drying box and dried with hot air at 70℃, and the moisture regain of the fiber after exiting the box is controlled at 8%; the pre-dried fiber is continuously fed into the baking machine and baked at 130℃ for 3min; after the fiber exits the baking machine, it is immediately introduced into the closed steam humidification box while hot, the ambient temperature in the humidification box is set at 40℃, the relative humidity is set at 85%, and the forced residence treatment is performed for 10min, and then cooled to room temperature through the cold air trough to obtain modified Juncao fiber; (4) Weigh 30% modified Juncao fiber, 55% cotton fiber and 15% polylactic acid fiber by mass percentage. Before mixing, control the balance moisture regain of each component in an independent humidity conditioning room. Control the modified Juncao fiber to 8%, the cotton fiber to 6% and the polylactic acid fiber to 0.5%. After mixing, loosen and mix through the opening and cleaning process, and then send it to the carding machine for carding. (5) The carding machine cylinder speed is set to 280 r / min, the doffer speed is set to 15 r / min, and the cover speed is set to 100 mm / min. The machine undergoes two drawing processes. In the roving process, the roving twist coefficient is controlled at 80. In the spinning process, ring spinning is used, and the spinning twist coefficient is controlled at 330 to produce 10-count blended bobbin yarn. (6) After the blended yarn obtained from the fine spinning process is wound into a winding tube, it is placed in a vacuum steaming box and treated under saturated steam at 60°C for 20 minutes to complete the twisting and obtain the finished blended yarn material.

[0041] Example 3: This example provides a method for preparing an antibacterial and antiviral biodegradable spunbond fiber blended yarn material, including the following steps: (1) Cut 10.0 kg of Juncao raw material into short segments with a length of 30-80 mm, put them into a reaction vessel, add 150 L of sodium hydroxide aqueous solution with a mass concentration of 8%, keep it at 100 °C for 60 min, and then wash it with water until neutral; add 150 L of hydrogen peroxide aqueous solution with a mass concentration of 4%, and bleach it at 80 °C for 60 min; after draining the liquid, replace it with 150 L of water, add 75.0 g of catalase, and treat it at 50 °C for 20 min to remove residual hydrogen peroxide; adjust the pH of the bath liquid to 5.0, add 300.0 g of compound enzyme preparation (composed of 200.0 g of cellulase and 100.0 g of xylanase), treat it at 55 °C for 50 min, and then raise the temperature to 85 °C to inactivate it; wash the treated fiber thoroughly with water, centrifuge to dehydrate, dry it at 70 °C, and open it with a cotton opener to obtain spinnable Juncao fiber with a length of 25-45 mm; (2) Preparation of solution A: Add 5L of deionized water to the mixing tank, then add 200.0g of tannic acid and 150.0g of nano zinc oxide in sequence. Stir at 500r / min for 45min at 50℃ to obtain a brownish-yellow sol. Preparation of solution B: Add 5L of deionized water to another mixing tank with a cooling jacket, then add 300.0g of quaternized chitosan obtained in Preparation Example 3 and stir to dissolve. After complete dissolution, slowly add 300.0g of citric acid, 150.0g of sodium hypophosphite, 200.0g of polyethylene glycol and 100.0g of glycerol in sequence. Turn on the jacket cooling and control the solution temperature at 30℃. Under continuous stirring, pump solution A into solution B at a uniform rate to obtain a composite working solution. The pH of the composite working solution is 4.2, and the temperature is maintained at 30℃. (3) The spinnable Juncao fiber prepared in step (1) is continuously passed through the composite working liquid impregnation tank in the form of a mesh belt, the impregnation temperature is controlled at 30℃, the impregnation time is 30min, and the residual rate of the double roller water mill is controlled at 80%; the fiber is transported to the mesh belt pre-drying box and dried with hot air at 80℃, and the moisture regain of the fiber after exiting the box is controlled at 12%; the pre-dried fiber is continuously fed into the baking machine and baked at 140℃ for 5min; after the fiber exits the baking machine, it is immediately introduced into the closed steam humidification box while hot, the ambient temperature in the humidification box is set at 50℃, the relative humidity is set at 95%, and the forced residence treatment is performed for 15min, and then cooled to room temperature through the cold air trough to obtain modified Juncao fiber; (4) Weigh 50% modified Juncao fiber, 35% cotton fiber and 15% polylactic acid fiber by mass percentage. Before mixing, control the balance moisture regain of each component in an independent humidity conditioning room. The modified Juncao fiber is controlled at 13%, the cotton fiber at 9% and the polylactic acid fiber at 2.0%. After mixing, the mixture is opened and mixed in the opening and cleaning process, and then sent to the carding machine for carding. (5) The carding machine cylinder speed is set to 380 r / min, the doffer speed is set to 30 r / min, and the cover speed is set to 140 mm / min. After three drawing processes, the roving twist coefficient is controlled at 120 in the roving process. In the spinning process, ring spinning is used and the spinning twist coefficient is controlled at 420 to produce 60 count blended bobbin yarn. (6) After the blended yarn obtained from the fine spinning process is wound into a winding tube, it is placed in a vacuum steaming box and treated under saturated steam at 85°C for 40 minutes to complete the twisting and obtain the finished blended yarn material.

[0042] Example 4: This example provides a method for preparing an antibacterial and antiviral biodegradable fungal grass fiber blended yarn material, including the following steps: (1) Prepare spinnable fungal grass fibers according to the method in step (1) of Example 1; (2) Prepare the composite working solution according to the method in step (2) of Example 1; (3) Prepare modified Juncao fiber according to the method in step (3) of Example 1; (4) Weigh 45% modified Juncao fiber, 45% cotton fiber and 10% polylactic acid fiber by mass percentage. Before mixing, control the balance moisture regain of each component in an independent humidity conditioning room. The modified Juncao fiber is controlled at 12%, the cotton fiber at 8%, and the polylactic acid fiber at 1.5%. After mixing, the mixture is opened and mixed in the opening and cleaning process, and then sent to the carding machine for carding. (5) The carding machine cylinder speed is set to 330 r / min, the doffer speed is set to 22 r / min, and the cover speed is set to 120 mm / min. After three drawing processes, the roving twist coefficient is controlled at 100 in the roving process. In the spinning process, ring spinning is used and the spinning twist coefficient is controlled at 380 to produce 40 count blended bobbin yarn. (6) After the blended yarn obtained from the fine spinning process is wound into a winding tube, it is placed in a vacuum steaming box and treated under saturated steam at 70°C for 30 minutes to complete the twisting and obtain the finished blended yarn material.

[0043] Comparative Example 1: Compared with Example 1, the difference is that in step (2) when preparing solution B, polyethylene glycol and glycerin are not added, while the other steps and process parameters are the same.

[0044] Comparative Example 2: Compared with Example 1, the difference is that sodium hypophosphite is not added when preparing solution B in step (2), while the other steps and process parameters are the same.

[0045] Comparative Example 3: Compared with Example 1, the difference is that after the fiber leaves the baking machine in step (3), it is not subjected to forced residence treatment in a closed steam humidification box, but is directly cooled to room temperature through a cold air trough. The other steps and process parameters are the same.

[0046] Comparative Example 4: Compared with Example 1, the difference is that citric acid and sodium hypophosphite are not added when preparing solution B in step (2), and the step of baking at 135°C for 4 minutes is cancelled in step (3). The pre-dried fiber is directly introduced into a closed steam humidifier for treatment. The remaining steps and process parameters are the same.

[0047] Test Example 1: Test objective: To verify the effect of polyethylene glycol and glycerin on the dispersion stability of multi-component composite working fluid.

[0048] The testing steps are as follows: 1. Take the composite working solutions prepared in Examples 1, 2, 3, 4 and Comparative Example 1 as test objects, measure 250 mL of each working solution and put it into a stoppered ground glass colorimetric tube, seal it and place it in a 25℃ constant temperature water bath for standing. 2. Using a UV-Vis spectrophotometer with deionized water as a reference, take 1.0 mL of each working solution and dilute it to 100 mL with deionized water to obtain a 100-fold dilution. Measure the transmittance of each sample at a wavelength of 600 nm after standing for 0 h, 4 h, 8 h, 12 h and 24 h. 3. After the static test, accurately weigh 100.0g of the mixture after 24 hours of static standing in each group, place it in a centrifuge tube, and centrifuge at 4000r / min for 15min. After discarding the supernatant, wash the bottom precipitate twice with deionized water, transfer it to a pre-dried weighing bottle to constant weight, and dry it in a vacuum oven at 80℃ to constant weight. Calculate the ratio of the mass of the dried precipitate to the initial theoretical total mass of the corresponding 100.0g working solution, and count it as the effective component sedimentation rate.

[0049] The test data is shown in Table 1.

[0050] .

[0051] According to the data in Table 1, the transmittance of the composite working solutions of Examples 1 to 4, after being diluted 100 times, was all above 97% at 0 h; after standing for 24 h, the transmittance remained between 92.3% and 96.8%, and the sedimentation rate of the effective components was between 0.9% and 3.4%. These results indicate that the composite working solutions of Examples 1 to 4 have good dispersion stability during the standing process.

[0052] Compared to Example 1, Comparative Example 1 did not add polyethylene glycol and glycerin when preparing solution B. The transmittance of the 100-fold diluted solution of Comparative Example 1 decreased from 85.3% at 0 h to 5.2% at 24 h, and the sedimentation rate of the active ingredient was 68.7%. These results indicate that, without the addition of polyethylene glycol and glycerin, the active ingredients in the composite working solution are more prone to aggregation and sedimentation, and the stability of the working solution is significantly reduced.

[0053] The composite working solution contains components such as quaternized chitosan, tannic acid, and nano-zinc oxide. Quaternized chitosan contains cationic groups, tannic acid contains polyphenolic hydroxyl groups, and nano-zinc oxide is easily affected by its dispersion state in an aqueous system. The polyethylene glycol added in the examples contains ether bonds and terminal hydroxyl groups, and glycerol contains a polyhydroxy structure. Both can form multi-point interactions with water molecules and functional components, which helps reduce the degree of aggregation between components, thereby improving the dispersion stability of the composite working solution.

[0054] Therefore, the results of Test Example 1 show that the addition of polyethylene glycol and glycerin helps to reduce the sedimentation rate of the active ingredients in the composite working solution and improve the stability of the composite working solution during the standing process.

[0055] Test Example 2: Test objective: To verify the introduction of functional components and the formation of cross-linked structures in the modified Juncao fiber of Example 1.

[0056] The testing steps are as follows: 1. Take 5.0g each of unmodified spinnable Juncao fiber and modified Juncao fiber prepared in Example 1, place them in deionized water containing 0.2% nonionic detergent by volume, wash continuously for 30min in a constant temperature water bath at 60℃, repeat the washing 3 times, and then transfer them to a vacuum drying oven at 60℃ to dry for 24h to reduce the influence of physically adsorbed components on the test results. 2. Cut the two dried fiber samples into small pieces, crush them using a micro pulverizer and pass them through a 200-mesh sieve. Accurately weigh 1.8 mg of sample powder and mix and grind it with 180.5 mg of potassium bromide powder that has been spectrally dried in an agate mortar until uniform. 3. Transfer the ground and mixed powder into a mold, and press it into a translucent sample sheet using a tablet press at 15 MPa. Fix the pressed sheet in the optical path of the Fourier transform infrared spectrometer, and set the spectral scanning range to 4000 cm⁻¹. -1 Up to 500cm -1 The number of scans was 32, and the resolution was 4cm. -1 Perform a scan and save the infrared transmittance data.

[0057] The test data are shown in Table 2, and the infrared spectral comparison results are as follows: Figure 1 As shown.

[0058] .

[0059] According to the data in Table 2, the unmodified spinnable sedge fiber has a thickness of 3348.6 cm. -1 and 1056.4cm -1 The infrared spectra at 1734.5 cm⁻¹ exhibit absorption peaks for both OH and COC stretching vibrations, reflecting the basic infrared characteristics of cellulose fibers. Example 1, modified Juncao fiber, retains the aforementioned characteristic peaks of the cellulose skeleton, and shows an absorption peak at 1734.5 cm⁻¹. -1 An absorption peak for the C=O stretching vibration of the ester bond was observed. This result indicates that an ester-bonded structure was formed in the modified Juncao fiber after treatment with citric acid, sodium hypophosphite, and baking.

[0060] Example 1: The modified Juncao fiber still measures 1612.4 cm. -1 and 1515.7cm-1 An absorption peak for the C=C stretching vibration of the benzene ring skeleton appears at 1478.2 cm⁻¹. -1 An absorption peak of CN bending vibration of quaternary ammonium group appeared at the location. The above characteristic peak corresponds to the structural characteristics of tannic acid and quaternized chitosan, indicating that tannic acid and quaternized chitosan were introduced into the modified Juncao fiber, and the corresponding characteristic signals can still be detected in the fiber sample after washing.

[0061] Combined with 1734.5cm -1 The absorption peaks of the C=O ester bond and the characteristic peaks related to tannic acid and quaternized chitosan indicate that a solid-bonded structure containing ester bonds was formed in the modified Juncao fiber of Example 1, and the binding strength of the functional components on the fiber was improved. These results demonstrate that the baking treatment with citric acid and sodium hypophosphite is beneficial to improving the fixation stability of functional components such as quaternized chitosan and tannic acid on Juncao fiber.

[0062] Test Example 3: Test objective: To investigate the effect of sodium hypophosphite on the color stability of Juncao fiber after high-temperature baking treatment.

[0063] The testing steps are as follows: 1. Take the unmodified spinnable Juncao fiber after bleaching, enzymatic softening and opening treatment in step (1), and the modified Juncao fiber obtained after treatment in Examples 1 to 4, Comparative Example 2 and Comparative Example 4 as test samples; balance each group of loose fibers in a humidified environment for 24 hours, and then use a parallel carder to card the fibers into a fiber web with uniform thickness and flat surface. 2. Turn on the desktop spectrophotometer. After it has warmed up and stabilized, use the standard black and white boards provided with the instrument to perform basic calibration. Set the measurement conditions to D65 standard light source, 10° standard observer's viewing angle, and exclude specular reflection mode. 3. Place the prepared fiber mesh flat on the test hole of the colorimeter and apply constant pressure to make the sample fit with the test hole; randomly select 5 test points on the surface of each group of samples for optical measurement, record the CIE whiteness value, and calculate the yellowness index YI according to the ASTM E313 standard. The arithmetic mean of the 5 test results is used as the final optical index data of the corresponding sample.

[0064] The test data is shown in Table 3.

[0065] .

[0066] According to the data in Table 3, the CIE whiteness values ​​of the modified Juncao fibers in Examples 1 to 4 ranged from 72.1 to 75.6, and the yellowness index ranged from 7.9 to 9.4. Compared with the unmodified spinnable Juncao fibers, the whiteness values ​​of Examples 1 to 4 decreased and the yellowness index increased, but the overall changes were small, indicating that the fibers still maintained good appearance and color after functionalization treatment.

[0067] Comparative Example 2, which did not add sodium hypophosphite when preparing the composite working solution, had a CIE whiteness value of 41.8 and a yellowness index of 38.5. Compared with Examples 1 to 4, the whiteness value of Comparative Example 2 was significantly lower and the yellowness index was significantly higher, indicating that under high-temperature baking conditions, the absence of sodium hypophosphite would cause more obvious yellowing or browning of the modified Juncao fiber.

[0068] Tannic acid molecules contain polyphenolic hydroxyl groups, and their color stability is affected by heat and oxygen during baking at 130°C to 140°C. In Examples 1 to 4, the addition of sodium hypophosphite resulted in a low yellowness index for the fibers, indicating that sodium hypophosphite in the citric acid crosslinking baking system helps reduce the high-temperature browning of tannic acid-related components and maintains the color stability of the modified Juncao fiber.

[0069] Comparative Example 4, without the addition of citric acid and sodium hypophosphite, and without the 135℃ baking step for 4 min, had a CIE whiteness value of 71.5 and a yellowness index of 9.7. This result indicates that the fiber color change was relatively small after eliminating the high-temperature baking. However, combined with the infrared test results of Test Example 2 and the subsequent wash resistance test results, it is clear that high-temperature baking treatment is beneficial for the fixation of functional components on the fiber. Therefore, the data in Table 3 demonstrates that the addition of sodium hypophosphite helps to improve the color stability of the modified Juncao fiber while maintaining the cross-linking baking effect.

[0070] Test Example 4: Test objective: To investigate the effects of polyethylene glycol, glycerin, and forced humidification treatment after baking on the mechanical properties of modified Juncao fiber.

[0071] The testing steps are as follows: 1. The final modified Juncao fiber was obtained as a test sample from the processing flow of Examples 1 to 4, Comparative Examples 1, 3 and 4. The loose fibers of each group were placed in a standard constant temperature and humidity chamber with a temperature of 20°C and a relative humidity of 65% for 24 hours to equilibrate and adjust the humidity. 2. Using the mid-section cutting and weighing method combined with a vibratory fineness tester, randomly select fiber samples from each group after humidification, measure the linear density of each fiber, and record the linear density data of a single fiber after removing outliers. 3. Fix both ends of the single fiber whose linear density has been measured in the upper and lower clamps of the single fiber strength tester. Set the clamp spacing to 20mm and the tensile speed to 10mm / min. Start the instrument to perform constant speed tensile until the fiber breaks. Record the absolute strength and elongation at the time of breakage. 4. For each sample group, 50 single fibers were repeatedly measured. The breaking strength was calculated by dividing the absolute strength by the linear density of the corresponding single fiber. The arithmetic mean of the 50 valid test results was calculated to obtain the single fiber breaking strength and breaking elongation of each group of modified Juncao fiber.

[0072] The test data is shown in Table 4.

[0073] .

[0074] According to the data in Table 4, the single-fiber breaking strength of the modified Juncao fibers in Examples 1 to 4 ranged from 3.86 cN / dtex to 4.18 cN / dtex, and the elongation at break ranged from 10.7% to 12.4%. Compared with Comparative Example 4, the breaking strength and elongation at break of Examples 1 to 4 were reduced; compared with Comparative Examples 1 and 3, the breaking strength and elongation at break of Examples 1 to 4 were significantly improved. These results indicate that adding polyethylene glycol and glycerol during crosslinking modification, combined with forced humidification treatment after baking, is beneficial for improving the mechanical properties of the modified Juncao fibers.

[0075] Comparative Example 1, without the addition of polyethylene glycol and glycerol to the composite working solution, exhibited a single fiber tensile strength of 3.12 cN / dtex and an elongation at break of 5.7%. Compared to Example 1, both the tensile strength and elongation at break of Comparative Example 1 were reduced. These results indicate that the addition of polyethylene glycol and glycerol helps reduce the impact of crosslinking treatment on fiber flexibility and helps maintain the deformability of the modified Juncao fiber during stretching.

[0076] Comparative Example 3, which eliminated the forced residence treatment in a closed steam humidification chamber after baking, exhibited a single fiber breaking strength of 2.75 cN / dtex and a breaking elongation of 4.6%. Compared to Example 1, the mechanical properties of Comparative Example 3 showed a more significant decrease. This result indicates that the forced humidification treatment after baking is beneficial for improving stress release during the fiber's transition from a high-temperature, low-moisture state to a room-temperature equilibrium state, thereby increasing the breaking elongation and breaking strength of the modified Juncao fiber.

[0077] Comparative Example 4, without the addition of citric acid and sodium hypophosphite, and without the 135℃ baking step for 4 min, showed a single fiber breaking strength of 4.35 cN / dtex and a breaking elongation of 12.6%. This result indicates that the fiber mechanical properties were well maintained without cross-linking baking treatment. However, combined with the results of Test Example 2 and subsequent wash resistance tests, it is clear that cross-linking baking treatment is beneficial for improving the fixation stability of the functional components on the Juncao fiber. Therefore, Examples 1 to 4, while maintaining the fixation effect of the functional components, ensured that the modified Juncao fiber retained mechanical properties suitable for subsequent spinning processing.

[0078] Test Example 5: Test objective: To investigate the processing adaptability of the modified Juncao fiber blended yarn prepared by the method of this invention during carding and yarn forming.

[0079] The testing steps are as follows: 1. The semi-finished cotton webs prepared by scaling up the same process in the blended production process of Examples 1 to 4 and Comparative Examples 1 to 4, as well as the finally spun blended yarn tubes, were used as test objects. 2. In the carding process, collect the waste cotton generated from the machine body, the cover plate, and the dust suction after each group processes 100kg of mixed raw materials. Weigh and calculate the percentage of the total waste cotton weight to the total weight of the fed raw materials. Record this as the waste cotton rate in the carding process. 3. Randomly select a sample of the mixed cotton layer at the inlet of the carding machine and a sample of the sliver at the outlet of the carding machine. Use a single fiber tester to measure the weight percentage of short fibers with a length of less than 16 mm in the cotton layer and the sliver respectively. Calculate the difference between the short fiber percentage of the sliver and the short fiber percentage of the cotton layer and record it as the short fiber increase rate. 4. Take the final spun yarn bobbins from each group and place them on a yarn evenness tester. Set the test speed to 400 m / min and the test time to 1 min. Measure and record the coefficient of variation (CV%) of the yarn evenness. 5. Draw a single yarn from each group of yarn bobbins, fix it between the upper and lower clamps of the single yarn strength tester, set the clamping distance to 500mm, the stretching speed to 500mm / min, test the breaking strength of the single yarn, and calculate the breaking strength in combination with the yarn linear density.

[0080] The test data are shown in Tables 5-1 and 5-2.

[0081] .

[0082] According to the data in Table 5-1, Example 1 and Comparative Examples 1 to 4 are all 30-count blended yarns, representing a comparison of the same specifications. In Example 1, the carding process waste rate was 4.8%, the short fiber increase rate was 2.5%, the yarn evenness CV was 14.6%, and the yarn breaking strength was 15.2 cN / tex. Compared to Example 1, Comparative Examples 1 to 4 showed varying degrees of increase in carding process waste rate, short fiber increase rate, and yarn evenness CV, while all showed varying degrees of decrease in yarn breaking strength. These results indicate that Example 1 exhibits good processing stability during carding and yarn forming.

[0083] According to the data in Table 5-2, Examples 2 to 4 produced 10-count, 60-count, and 40-count blended yarns, respectively. The carding process waste rate was 4.5% to 5.2%, the short fiber increase rate was 2.1% to 2.8%, the yarn evenness CV was 14.2% to 15.1%, and the yarn breaking strength was 14.8 cN / tex to 15.6 cN / tex. These results demonstrate that the method of the present invention can maintain good carding and yarn processing performance in the preparation of blended yarns of different counts.

[0084] Comparative Example 1, without the addition of polyethylene glycol and glycerin to the composite working solution, exhibited a cotton waste rate of 12.6% during the carding process, a short fiber increase rate of 9.7%, a yarn evenness CV of 18.8%, and a yarn breaking strength of 10.5 cN / tex. Compared to Example 1, Comparative Example 1 showed reduced processing stability and yarn quality, indicating that the addition of polyethylene glycol and glycerin is beneficial for improving the flexibility and yarn stability of the modified fibers during carding and drafting processes.

[0085] Comparative Example 3, which eliminated the forced residence treatment in a closed steam humidification box after baking, had a cotton waste rate of 14.3%, a short fiber increase rate of 11.4%, a yarn evenness CV of 19.5%, and a yarn breaking strength of 9.2 cN / tex. Compared with Example 1, Comparative Example 3 showed increased cotton waste rate, short fiber increase rate, and evenness CV, but decreased yarn breaking strength. These results indicate that forced humidification treatment after baking helps reduce fiber breakage during subsequent mechanical carding and improves yarn quality.

[0086] Comparative Example 4, without the addition of citric acid and sodium hypophosphite, and without the 135°C baking step for 4 minutes, showed a short fiber increase rate of 3.1%, close to that of Example 1. However, the cotton waste rate during the carding process was 10.8%, the yarn evenness CV was 17.2%, and the yarn breaking strength was 14.3 cN / tex. These results indicate that without crosslinking baking, the fiber's own breakage is relatively low, but the binding stability of functional components on the fiber is insufficient, affecting the stability of the carding process and the uniformity of the yarn.

[0087] The data from Tables 5-1 and 5-2 show that the combination of polyethylene glycol, glycerin, forced humidification treatment after baking, and cross-linking baking treatment with citric acid / sodium hypophosphite is beneficial in reducing the cotton loss rate and short fiber increase rate of modified Juncao fiber during the carding process, and is also beneficial in improving the yarn evenness and breaking strength of blended yarn.

[0088] Test Example 6: Test objective: To examine the antibacterial properties, antiviral properties, and functional retention of blended yarns after multiple standard washes.

[0089] The testing steps are as follows: 1. Using the blended yarns spun in Examples 1 to 4, Comparative Example 2 and Comparative Example 4 as test samples, and referring to GB / T 8629-2017 "Domestic Washing and Drying Procedures for Textile Testing", the yarns of each group were unwound into skeins and placed in a standard washing machine for washing. Standard detergent was used, and the yarns were continuously washed at a water temperature of 40°C. Yarn samples were collected after unwashing and after 20 washing cycles, and dried in an oven at 60°C for later use. 2. The antibacterial properties of the yarn were determined according to GB / T 20944.3-2008 "Evaluation of antibacterial properties of textiles - Part 3: Shaking method". Staphylococcus aureus ATCC 6538 and Escherichia coli ATCC 8099 were selected as test bacteria. 0.75g of yarn was cut into pieces and immersed in an Erlenmeyer flask containing bacterial solution of the specified concentration. The flask was placed on a constant temperature shaker at 37℃ and shaken at 150r / min for 18h. The sample solution was then diluted and spread on nutrient agar medium for colony counting and antibacterial rate calculation. 3. The antiviral properties of yarn were determined according to ISO 18184 "Determination of antiviral activity of textiles", using influenza A virus H1N1 (A / PR / 8 / 34) as the test model. Yarn samples were contacted with a quantitative virus suspension and incubated at room temperature for 2 hours. The reaction was terminated using an eluent containing a neutralizing agent. The logarithmic value of the virus titer in the recovered solution was determined by the host cell pathogenesis effect method or the plaque forming unit method. The virus reduction rate was calculated by comparing with an untreated blank sample.

[0090] The test data is shown in Table 6.

[0091] .

[0092] According to the data in Table 6, under the condition of 0 washes, Examples 1 to 4 all showed antibacterial rates of over 99% against Staphylococcus aureus and Escherichia coli, and H1N1 virus reduction rates of over 99%. After 20 standard washes, the antibacterial rate and H1N1 virus reduction rate of Examples 1 to 4 remained within the range of 93.85% to 97.28%. These results indicate that the blended yarns obtained in Examples 1 to 4 have good antibacterial and antiviral properties, and maintain a high functional retention rate after multiple standard washes.

[0093] Compared with Examples 1 to 4, Comparative Example 2 showed a significant decrease in antibacterial rate and H1N1 virus reduction rate after 20 standard washes. In Comparative Example 2, without the addition of sodium hypophosphite to the composite working solution, the antibacterial rate against Staphylococcus aureus decreased from 97.43% to 86.15%, the antibacterial rate against Escherichia coli decreased from 96.52% to 84.72%, and the H1N1 virus reduction rate decreased from 95.84% to 82.63%. These results indicate that the addition of sodium hypophosphite is beneficial in improving the retention of functional components after washing.

[0094] Comparative Example 4 did not include citric acid and sodium hypophosphite, and the high-temperature baking treatment was omitted. Comparative Example 4 still exhibited a high initial antibacterial rate and virus reduction rate at 0 washes, but after 20 standard washes, the antibacterial rate against Staphylococcus aureus decreased to 34.25%, the antibacterial rate against Escherichia coli decreased to 31.84%, and the H1N1 virus reduction rate decreased to 28.56%. These results indicate that, in the absence of citric acid / sodium hypophosphite crosslinking baking treatment, the wash resistance retention of functional components on the yarn is significantly reduced.

[0095] Examples 1 to 4 employed citric acid, sodium hypophosphite, and baking treatment to create a relatively stable bond between functional components such as quaternized chitosan, tannic acid, and nano-zinc oxide and the Juncao fiber. Quaternized chitosan contains cationic groups, tannic acid contains polyphenolic structures, and nano-zinc oxide contains inorganic antibacterial components. The combined use of these components enhances the antibacterial and antiviral properties of the blended yarn. Test results after 20 standard washes demonstrate that the cross-linking baking treatment improves the wash resistance retention of the functional components on the fiber.

[0096] Test Example 7: Test objective: To investigate the quality changes and tensile strength retention of the blended yarn material prepared by this invention under soil burial conditions.

[0097] The testing steps are as follows: 1. The blended yarn materials obtained in Examples 1 to 4 were used as test samples, and ordinary polyester blended yarn was used as a control sample. Ordinary polyester blended yarn is made by blending polyester fiber, raw cotton fiber and polylactic acid fiber, wherein polyester fiber is used to replace the modified Juncao fiber in Example 1, and the proportion of other fibers and spinning process are kept the same; 2. Take 10m long skeins from each group of yarn samples, and set up 5 parallel samples in each group. Place each sample in an environment with a temperature of 20℃ and a relative humidity of 65% for 24 hours to equilibrate, and weigh the initial dry mass of the sample, which is recorded as m0; at the same time, take yarn samples from the same batch to determine the breaking strength before embedding, which is recorded as F0; 3. Place each group of yarn samples into a nylon mesh bag with a 0.5mm aperture, and mark the sample number on the outside of the bag. Use natural soil with a humus content of 8.5% to 11.0%, a moisture content of 24% to 32%, and a pH of 6.6 to 7.4 as the burial medium. Bury the mesh bags containing the samples in the soil to a depth of 10cm. Maintain the ambient temperature at 25℃ to 30℃ during the experiment, and add deionized water every 7 days to keep the soil moisture content within the range of 24% to 32%. 4. The corresponding samples were removed after 60 and 90 days of burial, respectively. After removal, the samples were gently rinsed with deionized water to remove surface soil particles, and then dried in a 60℃ oven to constant weight. The dry mass after burial was recorded as m1. The mass loss rate was calculated using the following formula: Mass loss rate = (m0 - m1) / m0 × 100%; 5. After drying, place the sample back into an environment with a temperature of 20℃ and a relative humidity of 65% for 24 hours to equilibrate. Measure the tensile strength after embedding using a single-yarn tensile testing machine, and record it as F1. During the test, the clamping distance is set to 500mm, and the tensile speed is set to 500mm / min. Calculate the strength retention rate using the following formula: Strength retention rate = F1 / F0 × 100%; 6. Calculate the average value of 5 parallel samples in each group to obtain the mass loss rate and strength retention rate of each group of yarns under different soil burial times.

[0098] The test data is shown in Table 7.

[0099] .

[0100] According to the data in Table 7, the mass loss rates of Examples 1 to 4 after 60 days of soil burial were 16.3% to 22.5%, and after 90 days of soil burial, the mass loss rates were 28.1% to 36.8%. The mass loss rates of ordinary polyester blended yarn after 60 days and 90 days of soil burial were 4.6% and 8.3%, respectively. Compared with ordinary polyester blended yarn, Examples 1 to 4 had higher mass loss rates under the same burial conditions, indicating that the prepared blended yarn materials have a more obvious structural change trend in the soil environment.

[0101] According to the data in Table 7, the strength retention rate of Examples 1 to 4 after 60 days of soil burial was 71.4% to 81.2%, and the strength retention rate after 90 days of soil burial was 52.9% to 64.6%. The strength retention rate of ordinary polyester blended yarn after 90 days of soil burial was 86.5%. The above results indicate that, in addition to a certain degree of mass loss, the mechanical properties of the yarn in Examples 1 to 4 also decreased accordingly during soil burial.

[0102] As can be seen from the fiber composition of this invention, the modified Juncao fiber and raw cotton fiber in Examples 1 to 4 are both cellulose-based plant fibers, while the polylactic acid fiber is an aliphatic polyester biodegradable fiber. Under the combined effects of soil moisture, microorganisms, and temperature, the plant fiber components and polylactic acid fiber in the yarn can undergo certain structural changes. The citric acid crosslinking and baking treatment is mainly used to improve the binding stability of functional components such as quaternized chitosan, tannic acid, and nano-zinc oxide, without changing the composition characteristics of the blended system, which is mainly composed of plant fibers and biodegradable polymers.

[0103] Further analysis of the data from each embodiment reveals that Example 3 exhibited a mass loss rate of 36.8% after 90 days of soil burial, higher than Examples 1, 2, and 4. Example 2 showed a mass loss rate of 28.1% and a strength retention rate of 64.6% after 90 days of soil burial. The differences between the various embodiments are related to the modified fungal fiber content, yarn structure density, and the influence of the functional finishing layer on soil moisture penetration into the fibers. These results provide support for the environmental degradation performance of the blended yarn material of this invention in terms of both mass loss and strength retention.

[0104] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing an antibacterial and antiviral biodegradable fungal grass fiber blended yarn material, characterized in that, Includes the following steps: S1. Naturally dried short sections of giant reed grass are subjected to alkali treatment, bleaching, deoxygenation, enzymatic softening, drying and opening treatment in sequence to obtain unmodified spinnable reed grass fiber. S2. The unmodified spinnable Juncao fiber is impregnated in the composite working solution, followed by pre-drying and baking treatment to obtain baked Juncao fiber; the composite working solution is prepared by mixing the following components in parts by weight: 1000 parts water; 10-30 parts citric acid; 5-15 parts sodium hypophosphite; 2-20 parts tannic acid; 5-30 parts quaternized chitosan; 1-15 parts nano zinc oxide; 10-20 parts polyethylene glycol; 3-10 parts glycerol; The average particle size of the nano-zinc oxide is 30-50 nm. The polyethylene glycol is PEG-400, with an average molecular weight of 380-420; The specific implementation method of step S2 is as follows: the unmodified spinnable fungus grass fiber is immersed in the composite working solution for 15-30 minutes and then rolled, and the roll residue rate is controlled at 70%-80%; then it is pre-dried at 70-80℃, and the moisture regain rate of the fiber after pre-drying is controlled at 8%-12%; then it is baked at 130-140℃ for 3-5 minutes. S3. The baked Juncao fiber is subjected to closed steam humidification forced retention treatment, and after cooling, modified Juncao fiber is obtained. The specific implementation method of step S3 is as follows: while the baked mushroom fiber is still hot, it is introduced into a closed steam humidification box, the ambient temperature inside the closed steam humidification box is controlled at 40-50℃ and the relative humidity is 85%-95%, and the forced residence treatment is carried out for 10-15 minutes, and then cooled to room temperature. S4. The modified Juncao fiber is mixed with raw cotton fiber and polylactic acid fiber, and the antibacterial and antiviral biodegradable Juncao fiber blended yarn material is obtained through a spinning process. The composition of each fiber in the blended yarn material by weight percentage is as follows: modified hyacinth fiber: 30%-50%; raw cotton fiber: 35%-55%; polylactic acid fiber: 10%-15%; the sum of the weight percentages of the above components is 100%.

2. The method for preparing the antibacterial and antiviral biodegradable fungal and grass fiber blended yarn material according to claim 1, characterized in that, Each raw material component satisfies the following characteristic parameters: The naturally dried short sections of giant reed grass are 30-80 mm in length; The length of the unmodified spinnable fungus grass fiber is 25-45 mm; The length of the raw cotton fibers is 27-31 mm; The polylactic acid fiber has a fineness of 1.2-1.5D and a weight-average molecular weight of 100,000-150,000.

3. The method for preparing the antibacterial and antiviral biodegradable fungal and grass fiber blended yarn material according to claim 1, characterized in that, The degree of quaternization substitution of the quaternized chitosan is 42%-78%.

4. The method for preparing the antibacterial and antiviral biodegradable fungal and grass fiber blended yarn material according to claim 3, characterized in that, The preparation method of the quaternized chitosan includes the following steps: (1) Disperse chitosan in an aqueous acetic acid solution, heat to 60-70℃ and stir until completely dissolved to obtain a chitosan acetic acid solution; (2) Add 19-57 parts by weight of 3-chloro-2-hydroxypropyltrimethylammonium chloride aqueous solution to the system according to the ratio of 10 parts by weight of chitosan. Then add sodium hydroxide aqueous solution to adjust the pH of the system to 8.0-9.

0. Recycle under closed reflux at a constant temperature of 70-85℃ for 8-12 hours. (3) After the reaction is completed, cool to room temperature, precipitate in anhydrous acetone, collect the precipitate and redissolve it in deionized water, dialyze it with a dialysis bag for 3-5 days, and freeze dry to obtain quaternized chitosan.

5. The method for preparing the antibacterial and antiviral biodegradable fungal and grass fiber blended yarn material according to claim 1, characterized in that, In step S1, the alkali treatment uses a sodium hydroxide aqueous solution with a mass concentration of 2%-8% and is performed at 95-100℃ for 45-60 minutes. The bleaching process uses a 2%-4% hydrogen peroxide aqueous solution and is treated at 70-80℃ for 40-60 minutes. The deoxygenation is performed using catalase, and the catalase activity is ≥50000U / g. The enzymatic hydrolysis and softening process is performed using cellulase and xylanase, wherein the cellulase activity is ≥10000U / g and the xylanase activity is ≥50000U / g.

6. The method for preparing the antibacterial and antiviral biodegradable fungal grass fiber blended yarn material according to claim 1, characterized in that, In step S4, the spinning process sequentially includes opening and cleaning, carding, drawing, roving, spinning, winding, and twisting; wherein, in the carding process, the cylinder speed is 280-380 r / min, the doffer speed is 15-30 r / min, and the flats speed is 100-140 mm / min; the roving twist coefficient is 80-120, the spinning twist coefficient is 330-420, and 10-60 count blended yarn is spun.

Images