Medical natural antibacterial and antiviral mildew-proof wet non-woven fabric, preparation method and application thereof

Abstract

The application discloses a medical natural antibacterial and antiviral mildew-proof wet non-woven fabric and a preparation method and application thereof, and belongs to the technical field of medical polymer materials and textiles. The non-woven fabric is prepared from the following raw materials: polyethylene terephthalate long fibers, polyethylene terephthalate short fibers, vinylon fibers and natural antibacterial and antiviral ultraviolet slow-release glue solution. The non-woven fabric is endowed with natural and non-toxic antibacterial and antiviral effects by using the extract of Chinese herbal medicine effective components. Meanwhile, the mechanical properties and the antibacterial and antiviral capacity of the non-woven fabric can be effectively improved by adding nano materials with far infrared function after surface modification to prepare high-efficiency natural antibacterial and antiviral ultraviolet slow-release microcapsule glue solution. The method improves the added value and application field of the wet non-woven fabric and is convenient for large-scale processing and production. The prepared wet non-woven fabric has excellent performance indexes, good air permeability and an antibacterial and antiviral efficiency of 99.99%.

Description

Technical Field

[0001] This invention belongs to the field of medical polymer materials and textile technology, specifically relating to a medical natural antibacterial, antiviral and mildew-resistant wet-laid nonwoven fabric, its preparation method and application. Background Technology

[0002] In recent years, with the continuous improvement of people's living standards and the advancement of technology, the market demand for antibacterial and antiviral functions in the field of air purification is constantly rising. As a non-woven fabric product with high stiffness, wet-laid non-woven fabric is widely used as a skeleton material in composite filter elements in the fields of air purifiers, household air conditioners, automotive air conditioners, vacuum cleaners, and air purification in large clean rooms.

[0003] Traditional filter-based air purifiers primarily use fans to draw air through various stages of materials with filtration or adsorption functions to purify the air. However, after a period of use, the filter materials accumulate large amounts of small particles, fibers, microorganisms, and viruses, making them highly susceptible to bacterial and other harmful microorganisms in warm and humid environments. This poses a new threat to human health. Developing air filter materials with antibacterial and antiviral properties can significantly reduce the levels of bacteria, microorganisms, and viruses in the living environment, playing a crucial role in creating a new, livable microenvironment and protecting human health.

[0004] Currently, most antibacterial nonwoven fabrics on the market are prepared by blending inorganic antibacterial agents (spunbond or meltblown, etc.) or by finishing with antibacterial agents such as quaternary ammonium salts and complexed iodine. Examples include the medical protective antibacterial polypropylene fiber material QY40S developed in cooperation with Qingyang Petrochemical Company by the Lanzhou Chemical Research Center of the Petrochemical Research Institute of China National Petroleum Corporation; the organic nonwoven fabric made from silver ion zeolite from Ningbo University; and the electrostatic nanofiber nonwoven fabric with antibacterial and antiviral functions developed by the Jinhua Branch of the Beijing Research Institute of New Materials and Industrial Technology. While these nonwoven fabrics offer good antibacterial properties, their stiffness is insufficient to fulfill the role of a skeleton material due to limitations in their molding methods, and insufficient virus resistance is also a drawback restricting their application in the medical field.

[0005] For example, Chinese patent CN202010308442.8 discloses a method for preparing antibacterial meltblown nonwoven fabric, including the following steps: (1) treating polypropylene nonwoven fabric with oxygen plasma, and then grafting and modifying it to obtain modified polypropylene nonwoven fabric; (2) using propylenediamine and methyl methacrylate as raw materials, polymerizing them into an amino-terminated hyperbranched polymer, and then preparing the modified hyperbranched polymer by polycondensation reaction of carboxymethyl chitosan and the amino-terminated hyperbranched polymer; (3) adding copper chloride solution to the modified hyperbranched polymer aqueous solution, and adding sodium borohydride solution dropwise under nitrogen protection and ice bath conditions. After the reaction is completed, the modified polypropylene nonwoven fabric is immersed in the modified hyperbranched polymer aqueous solution for impregnation treatment, and then dried to obtain antibacterial meltblown nonwoven fabric.

[0006] To date, no research or preparation methods have been reported for the large-scale industrial production of natural antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabrics. Developing a wet-laid nonwoven fabric with natural antibacterial, antiviral, and mildew-resistant functions has broad market prospects. Summary of the Invention

[0007] This invention aims to fill the market gap in industrialized wet-laid nonwoven fabrics with antibacterial, antiviral, and anti-mildew properties, and to meet the demand for nonwoven fabrics with natural antibacterial, antiviral, and anti-mildew properties in modern civilian and medical fields. It provides a wet-laid nonwoven fabric with natural antibacterial, antiviral, and anti-mildew properties and high stiffness, along with its preparation method. The nonwoven fabric with natural antibacterial, antiviral, and anti-mildew properties of this invention, while possessing high air permeability, also exhibits high stiffness due to the unique structural design of wet-laid nonwoven fabrics, ensuring mechanical properties while maintaining gas permeability. Furthermore, the nonwoven fabric of this invention also has advantages such as chemical stability, resistance to light aging, and low moisture regain.

[0008] To achieve the above-mentioned technical objectives, the technical solution adopted by the present invention is as follows:

[0009] A medical-grade natural antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabric is prepared from the following raw materials: polyethylene terephthalate long fibers, polyethylene terephthalate short fibers, vinylon fibers, and natural antibacterial, antiviral, and UV-controlled adhesive liquid.

[0010] Furthermore, the mass ratio of the polyethylene terephthalate long fiber, polyethylene terephthalate short fiber, vinylon fiber, and natural antibacterial and antiviral UV sustained-release adhesive is (2-3):(1-2):(2-3):(3-4).

[0011] Furthermore, the length of the long polyethylene terephthalate fiber is 11-14 mm, and the length of the short polyethylene terephthalate fiber is 5-8 mm.

[0012] Furthermore, the preparation method of the natural antibacterial and antiviral UV sustained-release adhesive is as follows:

[0013] (1) Preparation of surface-modified nanomaterials: The nanomaterial powder and the dispersant are mixed at a mass ratio of (5-50):1, and then added to a nanoball mill and ground until uniformly dispersed to prepare surface-modified nanomaterials;

[0014] (2) Extraction of natural antibacterial and antiviral components: After mixing the Chinese herbal medicines, they are crushed and ground into powder. The solid powder is soaked in distilled water and heated and distilled at 80-100℃. The distillate is the water extract of the Chinese herbal medicines. The residue is then added to an ethanol solution with a mass fraction of 50-60% and 3-5 times its weight and refluxed three times. The reflux extraction is assisted by ultrasound with a power of 80-100W and a frequency of 20-50KHz. The mixture is filtered, centrifuged and the ethanol is recovered under reduced pressure to obtain the alcohol extract of the Chinese herbal medicines. The water extract and the alcohol extract are mixed evenly to obtain an aqueous solution containing natural antibacterial and antiviral components such as chlorogenic acid, forsythoside, glycyrrhizic acid, tryptophan, and caffeic acid, which are the natural antibacterial and antiviral components.

[0015] (3) Preparation of natural antibacterial and antiviral UV sustained-release adhesive by improved multiphase emulsion method: The nanomaterial dispersant and natural antibacterial and antiviral components are dispersed in the low-toxicity solvent ethyl acetate and emulsified to obtain the primary emulsion; Collagen, melamine, crosslinking agent and water are mixed evenly in a mass ratio of (10):(0.5-2):(0.1-2):(100) to obtain a mixed aqueous solution; The primary emulsion is dispersed in the mixed aqueous solution, and Lewis acid and emulsifying dispersant are added, and the mixture is continuously stirred and heated (heating temperature not higher than 70℃) to make the solvent evaporate. During the phase inversion process, the nanomaterial dispersant and the effective antiviral components are uniformly mixed and form natural antibacterial and antiviral microcapsules to prepare a natural antibacterial and antiviral UV sustained-release adhesive suitable for wet nonwoven fabrics.

[0016] A schematic diagram of the improved multiphase emulsion preparation method of this invention is shown below. Figure 1 As shown, traditional microcapsule preparation methods, such as Figure 2 As shown.

[0017] Furthermore, the nanomaterial powder is one or more of graphene, zinc oxide, or zirconium oxide; and the dispersant is one or more of polyoxyethylene octylphenol ether, fatty alcohol polyoxyethylene ether, and castor oil polyoxyethylene ether.

[0018] Furthermore, the Chinese herbal medicine mentioned in step (2) is one or more of the following: Isatis root, honeysuckle, dandelion, mugwort, and chinaberry leaves.

[0019] Furthermore, the crosslinking agent in step (3) is an organic compound containing at least 2 aldehyde groups (-CHO); the emulsifying dispersant is a nonionic surfactant, such as castor oil polyoxyethylene ether.

[0020] Furthermore, the crosslinking agent in step (3) is one or more of glyoxal, glutaraldehyde, and triacetaldehyde.

[0021] Furthermore, in step (3), the ratio of surface-modified nanomaterials, natural antibacterial and antiviral components, and ethyl acetate is 1g:10mL:50mL; the volume ratio of the colostrum and the mixed aqueous solution is 1:1; and the amount of Lewis acid and emulsifying dispersant added is 0.1%-2% of the total mass of the colostrum and the mixed aqueous solution.

[0022] Furthermore, Lewis acids can be selected from aluminum chloride, ferric chloride, boron trifluoride, niobium pentachloride, and trifluoromethanesulfonates of lanthanides. As reaction catalysts, Lewis acids can lower the reaction temperature to below 70°C, ensuring that collagen and natural antibacterial and antiviral components are not decomposed.

[0023] A method for preparing a medical-grade natural antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabric includes the following preparation steps:

[0024] (1) Preparation of natural antibacterial and antiviral UV sustained-release gel;

[0025] (2) The raw materials, polyethylene terephthalate long fibers, polyethylene terephthalate short fibers, vinylon fibers, and natural antibacterial and antiviral UV slow-release adhesive, are ultrasonically dispersed in a raw material tank according to the proportion, and then formed into a web and cured in a wet nonwoven fabric production line. The prepared wet nonwoven fabric is washed with water, ultrasonically removed for impurities and defects, and then subjected to thermal stretching and shaping treatment to obtain the medical natural antibacterial, antiviral and mildew-resistant wet nonwoven fabric.

[0026] This invention relates to the application of a medical-grade, natural, antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabric, used as an air filtration material, catalyst carrier, or adsorbent. This nonwoven fabric can be used as a catalyst carrier to prepare high-performance catalysts via vapor deposition, or as a substrate to enhance functionality through other loading methods, thus preparing air filtration materials, catalytic materials, adsorbent materials, etc., with multiple functions.

[0027] Beneficial effects

[0028] (1) This invention utilizes extracts from traditional Chinese medicine to prepare antibacterial and antiviral adhesives, endowing nonwoven fabrics with highly efficient antibacterial and antiviral effects. First, inorganic materials with far-infrared release functions are used to prepare nano-dispersed materials. The selection of nanomaterials with far-infrared functions, such as graphene, zinc oxide, and zirconium oxide, can effectively stimulate the efficacy of effective active antibacterial and antiviral components in traditional Chinese medicines such as Isatis indigotica, honeysuckle, and dandelion, and the two have a synergistic effect. Subsequently, the volatile oil of the compound plant extract prepared under the optimal process is encapsulated by acid and alkali resistant melamine microcapsule technology using a multiphase emulsion method, and combined with UV-degradable protein materials to prepare natural antibacterial and antiviral UV sustained-release microcapsules. These natural antibacterial and antiviral UV sustained-release microcapsules not only have a smooth and round surface, but also can slowly degrade under sunlight (UV) irradiation, which facilitates the outward diffusion of the effective core material during use and slow release, so as to achieve the long-lasting and highly efficient antibacterial and antiviral function of this product within the designed service life.

[0029] (2) At the same time, the natural antibacterial and antiviral components and nanomaterials encapsulated in the microcapsules can effectively improve the mechanical properties and antibacterial and antiviral capabilities of the nonwoven fabric. The medical-grade natural antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabric of the present invention has a fiber fineness of 12-40μm, a breaking strength greater than 130N / 50mm and a transverse strength greater than 90N / 50mm, an air permeability greater than 3500mm / s, a pressure difference less than 130MPa, and a stiffness greater than 210mg in the longitudinal direction and greater than 100mg in the transverse direction, with excellent comprehensive performance.

[0030] (3) The method of this invention is applicable to the preparation of medical-grade natural antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabrics, which improves the added value and application fields of wet-laid nonwoven fabrics, facilitates large-scale processing and production, and is simple, easy to operate, and convenient to implement. The prepared medical-grade natural antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabric has excellent performance in all indicators, good air permeability, and antibacterial and antiviral efficiency of up to 99.99%. Attached Figure Description

[0031] Figure 1 A schematic diagram of the improved multiphase emulsion preparation method;

[0032] Figure 2 This is a schematic diagram of a traditional microcapsule preparation method;

[0033] Figure 3 Photograph of the wet-laid nonwoven fabric with natural antibacterial, antiviral, and mildew-resistant properties of this invention;

[0034] Figure 4 Microscopic photograph of ordinary wet-laid nonwoven fabric;

[0035] Figure 5 Microscopic image of a wet-laid nonwoven fabric with natural antibacterial, antiviral, and mildew-resistant properties, showing a large number of microcapsule structures mixed in. Detailed Implementation

[0036] The technical solution of the present invention will be further described below with reference to specific embodiments, but it is not limited thereto.

[0037] Example 1

[0038] A medical-grade natural antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabric is prepared from the following raw materials: polyethylene terephthalate long fibers, polyethylene terephthalate short fibers, vinylon fibers, and natural antibacterial, antiviral, and UV-controlled adhesive liquid.

[0039] The mass ratio of polyethylene terephthalate long fibers, polyethylene terephthalate short fibers, vinylon fibers, and natural antibacterial and antiviral UV sustained-release adhesive is 3:1:3:3.

[0040] The length of the long polyethylene terephthalate fiber is 12 mm, and the length of the short polyethylene terephthalate fiber is 6 mm.

[0041] The preparation method of the natural antibacterial and antiviral UV sustained-release adhesive is as follows:

[0042] (1) Preparation of nanomaterial dispersant: The nanomaterial powder and the dispersant are mixed at a mass ratio of 5:1, and then added to a nanoball mill and ground until uniformly dispersed to prepare nanomaterial dispersant;

[0043] (2) Extraction of natural antibacterial and antiviral components: The same amount of Isatis root and honeysuckle were mixed and ground into powder. The solid powder was soaked in distilled water and heated and distilled at 80-100℃. The distillate was the water extract of Chinese herbal medicine. The residue was then added to a 50% ethanol solution with a mass fraction of 3 times its weight and refluxed three times. The reflux extraction was assisted by ultrasound with a power of 80W and a frequency of 20KHz. The mixture was filtered, centrifuged and the ethanol was recovered under reduced pressure to obtain the alcohol extract of Chinese herbal medicine. The water extract and the alcohol extract were mixed evenly to obtain the natural antibacterial and antiviral components.

[0044] (3) Preparation of natural antibacterial and antiviral UV sustained-release gel by improved multiphase emulsion method: The nanomaterial dispersant and natural antibacterial and antiviral components are dispersed in the solvent ethyl acetate and emulsified to obtain the primary emulsion; collagen, melamine, crosslinking agent and water are mixed evenly in a mass ratio of 10:0.5:0.1:100 to obtain a mixed aqueous solution; the primary emulsion is dispersed into the mixed aqueous solution, and Lewis acid and emulsifying dispersant are added, and the mixture is continuously stirred and heated to allow the solvent to evaporate, thereby obtaining the natural antibacterial and antiviral UV sustained-release gel.

[0045] The nanomaterial is graphene, and the dispersant is polyoxyethylene octylphenol ether.

[0046] The emulsifying dispersant is castor oil polyoxyethylene ether.

[0047] The crosslinking agent in step (3) is glyoxal.

[0048] In step (3), the ratio of surface-modified nanomaterials, natural antibacterial and antiviral components, and ethyl acetate is 1g:10mL:50mL; the volume ratio of the colostrum and the mixed aqueous solution is 1:1; and the amount of Lewis acid and emulsifying dispersant added is 0.1% of the total mass of the colostrum and the mixed aqueous solution.

[0049] Lewis acid is aluminum chloride.

[0050] A method for preparing a medical-grade natural antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabric includes the following preparation steps:

[0051] (1) Preparation of natural antibacterial and antiviral UV sustained-release gel;

[0052] (2) The raw materials, polyethylene terephthalate long fibers, polyethylene terephthalate short fibers, vinylon fibers, and natural antibacterial and antiviral UV slow-release adhesive, are ultrasonically dispersed in a raw material tank according to the proportion, and then formed into a web and cured in a wet nonwoven fabric production line. The prepared wet nonwoven fabric is washed with water, ultrasonically removed for impurities and defects, and then subjected to thermal stretching and shaping treatment to obtain the medical natural antibacterial, antiviral and mildew-resistant wet nonwoven fabric.

[0053] The nonwoven fabric of this invention can be used as a catalyst carrier to prepare high-performance catalysts through vapor deposition, or as a substrate to improve functionality through other loading methods, to prepare air filter materials, catalytic materials, adsorbent materials, etc. with multiple functions.

[0054] Example 2

[0055] A medical-grade natural antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabric is prepared from the following raw materials: polyethylene terephthalate long fibers, polyethylene terephthalate short fibers, vinylon fibers, and natural antibacterial, antiviral, and UV-controlled adhesive liquid.

[0056] The mass ratio of polyethylene terephthalate long fibers, polyethylene terephthalate short fibers, vinylon fibers, and natural antibacterial and antiviral UV sustained-release adhesive is 3:1:2:4.

[0057] The length of the long polyethylene terephthalate fiber is 11 mm, and the length of the short polyethylene terephthalate fiber is 8 mm.

[0058] The preparation method of the natural antibacterial and antiviral UV sustained-release adhesive is as follows:

[0059] (1) Preparation of nanomaterial dispersant: The nanomaterial powder and the dispersant are mixed at a mass ratio of 50:1, and then added to a nanoball mill and ground until uniformly dispersed to prepare nanomaterial dispersant;

[0060] (2) Extraction of natural antibacterial and antiviral components: Licorice, honeysuckle and dandelion are mixed in equal weight and then ground into powder. The solid powder is soaked in distilled water and heated and distilled at 80-100℃. The distillate is the water extract of Chinese herbal medicine. The residue is then added to a 55% ethanol solution with a mass fraction of 4 times its weight and refluxed three times. The reflux extraction is assisted by ultrasound with a power of 90W and a frequency of 40KHz. After filtration, centrifugation and ethanol recovery under reduced pressure, the alcohol extract of Chinese herbal medicine is obtained. The water extract and alcohol extract are mixed evenly to obtain natural antibacterial and antiviral components.

[0061] (3) Preparation of natural antibacterial and antiviral UV sustained-release gel by improved multiphase emulsion method: The nanomaterial dispersant and natural antibacterial and antiviral components are dispersed in the solvent ethyl acetate and emulsified to obtain the primary emulsion; collagen, melamine, crosslinking agent and water are mixed evenly in a mass ratio of 10:1:1:100 to obtain a mixed aqueous solution; the primary emulsion is dispersed into the mixed aqueous solution, and Lewis acid and emulsifying dispersant are added, and the mixture is continuously stirred and heated to allow the solvent to evaporate, thereby obtaining the natural antibacterial and antiviral UV sustained-release gel.

[0062] The nanomaterial is zinc oxide; the dispersant is fatty alcohol polyoxyethylene ether.

[0063] The emulsifying dispersant is a nonionic surfactant, fatty acid monoglyceride.

[0064] The crosslinking agent in step (3) is glutaraldehyde.

[0065] In step (3), the ratio of surface-modified nanomaterials, natural antibacterial and antiviral components, and ethyl acetate is 1g:10mL:50mL; the volume ratio of the colostrum and the mixed aqueous solution is 1:1; and the amount of Lewis acid and emulsifying dispersant added is 1% of the total mass of the colostrum and the mixed aqueous solution.

[0066] Lewis acid is ferric chloride

[0067] A method for preparing a medical-grade natural antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabric includes the following preparation steps:

[0068] (1) Preparation of natural antibacterial and antiviral UV sustained-release gel;

[0069] (2) The raw materials, polyethylene terephthalate long fibers, polyethylene terephthalate short fibers, vinylon fibers, and natural antibacterial and antiviral UV slow-release adhesive, are ultrasonically dispersed in a raw material tank according to the proportion, and then formed into a web and cured in a wet nonwoven fabric production line. The prepared wet nonwoven fabric is washed with water, ultrasonically removed for impurities and defects, and then subjected to thermal stretching and shaping treatment to obtain the medical natural antibacterial, antiviral and mildew-resistant wet nonwoven fabric.

[0070] Example 3

[0071] A medical-grade natural antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabric is prepared from the following raw materials: polyethylene terephthalate long fibers, polyethylene terephthalate short fibers, vinylon fibers, and natural antibacterial, antiviral, and UV-controlled adhesive liquid.

[0072] The mass ratio of polyethylene terephthalate long fibers, polyethylene terephthalate long fibers, vinylon fibers, and natural antibacterial and antiviral UV sustained-release adhesive is 2:2:2:4.

[0073] The length of the long polyethylene terephthalate fiber is 14 mm, and the length of the short polyethylene terephthalate fiber is 5 mm.

[0074] The preparation method of the natural antibacterial and antiviral UV sustained-release adhesive is as follows:

[0075] (1) Preparation of nanomaterial dispersant: The nano powder and the dispersant are mixed at a mass ratio of 40:1, and then added to a nanoball mill and ground until uniformly dispersed to prepare nanomaterial dispersant;

[0076] (2) Extraction of natural antibacterial and antiviral components: Honeysuckle, Artemisia argyi and Isatis indigotica were mixed in a mass ratio of 1:10:1 and then ground into powder. The solid powder was soaked in distilled water and heated and distilled at 80-100℃. The distillate was the water extract of Chinese herbal medicine. The residue was then added to a 60% ethanol solution with a mass fraction of 5 times its weight and refluxed three times. The reflux extraction was assisted by ultrasound with a power of 100W and a frequency of 50KHz. The mixture was filtered, centrifuged and the ethanol was recovered under reduced pressure to obtain the alcohol extract of Chinese herbal medicine. The water extract and the alcohol extract were mixed evenly to obtain the natural antibacterial and antiviral components.

[0077] (3) Preparation of natural antibacterial and antiviral UV sustained-release gel by improved multiphase emulsion method: The nanomaterial dispersant and natural antibacterial and antiviral components are dispersed in the solvent ethyl acetate and emulsified to obtain the primary emulsion; collagen, melamine, crosslinking agent and water are mixed evenly in a mass ratio of 10:2:2:100 to obtain a mixed aqueous solution; the primary emulsion is dispersed into the mixed aqueous solution, and Lewis acid and emulsifying dispersant are added, and the mixture is continuously stirred and heated to allow the solvent to evaporate, thereby obtaining the natural antibacterial and antiviral UV sustained-release gel.

[0078] The nanomaterial is zirconium oxide; the dispersant is castor oil polyoxyethylene ether.

[0079] The emulsifying dispersant is castor oil polyoxyethylene ether.

[0080] The crosslinking agent in step (3) is tricornaldehyde.

[0081] In step (3), the ratio of surface-modified nanomaterials, natural antibacterial and antiviral components, and ethyl acetate is 1g:10mL:50mL; the volume ratio of the colostrum and the mixed aqueous solution is 1:1; and the amount of Lewis acid and emulsifying dispersant added is 2% of the total mass of the colostrum and the mixed aqueous solution.

[0082] The Lewis acid is boron trifluoride.

[0083] A method for preparing a medical-grade natural antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabric includes the following preparation steps:

[0084] (1) Preparation of natural antibacterial and antiviral UV sustained-release gel;

[0085] (2) The raw materials, polyethylene terephthalate long fibers, polyethylene terephthalate short fibers, vinylon fibers, and natural antibacterial and antiviral UV slow-release adhesive, are ultrasonically dispersed in a raw material tank according to the proportion, and then formed into a web and cured in a wet nonwoven fabric production line. The prepared wet nonwoven fabric is washed with water, ultrasonically removed for impurities and defects, and then subjected to thermal stretching and shaping treatment to obtain the medical natural antibacterial, antiviral and mildew-resistant wet nonwoven fabric.

[0086] This invention relates to the application of a medical-grade, natural, antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabric, used as an air filtration material, catalyst carrier, or adsorbent. This nonwoven fabric can be used as a catalyst carrier to prepare high-performance catalysts via vapor deposition, or as a substrate to enhance functionality through other loading methods, thus preparing air filtration materials, catalytic materials, adsorbent materials, etc., with multiple functions.

[0087] Comparative Example 1

[0088] A medical-grade natural antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabric is prepared from the following raw materials: polyethylene terephthalate long fibers, polyethylene terephthalate short fibers, vinylon fibers, and natural antibacterial, antiviral, and UV-controlled adhesive liquid.

[0089] The mass ratio of polyethylene terephthalate long fibers, polyethylene terephthalate long fibers, vinylon fibers, and natural antibacterial and antiviral UV sustained-release adhesive is 2:2:2:4.

[0090] The length of the long polyethylene terephthalate fiber is 14 mm, and the length of the short polyethylene terephthalate fiber is 5 mm.

[0091] The preparation method of the natural antibacterial and antiviral UV sustained-release adhesive is as follows:

[0092] (1) Extraction of natural antibacterial and antiviral components: Honeysuckle, Artemisia argyi and Isatis indigotica were mixed in a mass ratio of 1:10:1 and then ground into powder. The solid powder was soaked in distilled water and heated and distilled at 80-100℃. The distillate was a water extract of Chinese herbal medicine. The residue was then added to a 60% ethanol solution with a mass fraction of 5 times its weight and refluxed three times. The reflux extraction was assisted by ultrasound with a power of 100W and a frequency of 50KHz. The mixture was filtered, centrifuged and the ethanol was recovered under reduced pressure to obtain an alcohol extract of Chinese herbal medicine. The water extract and the alcohol extract were mixed evenly to obtain natural antibacterial and antiviral components.

[0093] (2) Preparation of natural antibacterial and antiviral UV sustained-release gel by improved multiphase emulsion method: The natural antibacterial and antiviral components are dispersed in the solvent ethyl acetate and emulsified to obtain the primary emulsion; collagen, melamine, crosslinking agent and water are mixed evenly in a mass ratio of 10:2:2:100 to obtain a mixed aqueous solution; the primary emulsion is dispersed into the mixed aqueous solution, and Lewis acid and emulsifying dispersant are added, and the mixture is continuously stirred and heated to allow the solvent to evaporate, thereby obtaining the natural antibacterial and antiviral UV sustained-release gel.

[0094] The nanomaterial is zirconium oxide; the dispersant is castor oil polyoxyethylene ether.

[0095] The emulsifying dispersant is castor oil polyoxyethylene ether.

[0096] The crosslinking agent in step (2) is tricornaldehyde.

[0097] Step (2) The ratio of natural antibacterial and antiviral components to ethyl acetate is 10 mL: 50 mL; the volume ratio of colostrum to mixed aqueous solution is 1:1; the amount of Lewis acid and emulsifying dispersant added is 2% of the total mass of colostrum and mixed aqueous solution.

[0098] The Lewis acid is boron trifluoride.

[0099] A method for preparing a medical-grade natural antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabric includes the following preparation steps:

[0100] (1) Preparation of natural antibacterial and antiviral UV sustained-release gel;

[0101] (2) The raw materials, polyethylene terephthalate long fibers, polyethylene terephthalate short fibers, vinylon fibers, and natural antibacterial and antiviral UV slow-release adhesive, are ultrasonically dispersed in a raw material tank according to the proportion, and then formed into a web and cured in a wet nonwoven fabric production line. The prepared wet nonwoven fabric is washed with water, ultrasonically removed for impurities and defects, and then subjected to thermal stretching and shaping treatment to obtain the medical natural antibacterial, antiviral and mildew-resistant wet nonwoven fabric.

[0102] In this comparative example, except that no nanomaterial dispersant was added during the preparation of the natural antibacterial and antiviral UV sustained-release adhesive, the other raw materials and preparation methods were the same as in Example 3.

[0103] Comparative Example 2

[0104] A medical-grade natural antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabric is prepared from the following raw materials: polyethylene terephthalate long fibers, polyethylene terephthalate short fibers, vinylon fibers, and natural antibacterial and antiviral adhesive.

[0105] The mass ratio of polyethylene terephthalate long fibers, polyethylene terephthalate long fibers, vinylon fibers, and natural antibacterial and antiviral adhesive is 2:2:2:4.

[0106] The length of the long polyethylene terephthalate fiber is 14 mm, and the length of the short polyethylene terephthalate fiber is 5 mm.

[0107] The preparation method of the natural antibacterial and antiviral adhesive is as follows:

[0108] (1) Preparation of nanomaterial dispersant: The nanomaterial and the dispersant are mixed at a mass ratio of 40:1, and then added to a nanoball mill and ground until uniformly dispersed to prepare nanomaterial dispersant;

[0109] (2) Extraction of natural antibacterial and antiviral components: Honeysuckle, Artemisia argyi and Isatis indigotica were mixed in a mass ratio of 1:10:1 and ground into powder. The solid powder was soaked in distilled water and heated and distilled at 80-100℃. The distillate was a water extract of Chinese herbal medicine. The residue was then added to a 60% ethanol solution with a mass fraction of 5 times its weight and refluxed three times. The reflux extraction was assisted by ultrasound with a power of 100W and a frequency of 50KHz. The mixture was filtered, centrifuged and the ethanol was recovered under reduced pressure to obtain an alcohol extract of Chinese herbal medicine. The water extract and the alcohol extract were mixed evenly to obtain natural antibacterial and antiviral components.

[0110] (3) Preparation of natural antibacterial and antiviral gels using traditional microencapsulation methods:

[0111] The natural antibacterial and antiviral components are dispersed in the solvent ethyl acetate and emulsified to obtain the primary emulsion; formaldehyde (37% aqueous solution), melamine, alkaline catalyst and water are mixed evenly in a mass ratio of 10:2:2:100 to obtain a mixed solution; the primary emulsion is dispersed into the mixed solution, and the mixture is continuously stirred and heated to allow the solvent to evaporate, thus obtaining a natural antibacterial and antiviral adhesive.

[0112] The nanomaterial is zirconium oxide; the dispersant is castor oil polyoxyethylene ether.

[0113] The emulsifying dispersant is castor oil polyoxyethylene ether.

[0114] The alkaline catalyst in step (3) is sodium hydroxide.

[0115] In step (3), the ratio of surface-modified nanomaterials, natural antibacterial and antiviral components, and ethyl acetate is 1g:10mL:50mL; the volume ratio of the primary emulsion and the mixed aqueous solution is 1:1; and the amount of alkaline catalyst and emulsifying dispersant added is 2% of the total mass of the primary emulsion and the mixed aqueous solution.

[0116] A method for preparing a medical-grade natural antibacterial, antiviral, and mildew-resistant wet-laid nonwoven fabric includes the following preparation steps:

[0117] (1) Preparation of natural antibacterial and antiviral adhesive liquid;

[0118] (2) The raw materials, polyethylene terephthalate long fibers, polyethylene terephthalate short fibers, vinylon fibers, and natural antibacterial and antiviral adhesive, are ultrasonically dispersed in a raw material tank according to the proportion, and then formed into a web and solidified in a wet nonwoven fabric production line. The prepared wet nonwoven fabric is washed with water, ultrasonically removed for impurities and defects, and then subjected to thermal stretching and shaping treatment to obtain the medical natural antibacterial, antiviral and mildew-resistant wet nonwoven fabric.

[0119] In this comparative example, except that the improved multiphase emulsion method was not used in the preparation of the natural antibacterial and antiviral UV sustained-release adhesive during the preparation of the antibacterial and antiviral adhesive, i.e., the traditional method was used, all other raw materials and preparation methods were the same as in Example 3.

[0120] Performance testing

[0121] The nonwoven fabrics obtained in the examples and comparative examples were subjected to performance tests, and the test methods are as follows: antibacterial performance test GB / T20944.2-2007 "Evaluation of antibacterial properties of textiles - Part II: Absorption method"; antiviral performance test according to ISO18184:2019; strength performance test according to FZ / T 60005-1991 "Determination of breaking strength and elongation at break of nonwoven fabrics"; air permeability test according to GB / T 24218.15-2018 "Textiles - Test methods for nonwoven fabrics".

[0122] Table 1 Performance Test Results

[0123]

[0124] As can be seen from the data in the table, the nonwoven fabrics in the embodiments of the present invention exhibit good mechanical properties, stiffness, and antibacterial and antiviral capabilities. However, in Comparative Example 1, which lacks nano-modification, and Comparative Example 2, which alters the preparation method of the antibacterial and antiviral adhesive, the antibacterial and antiviral capabilities of the nonwoven fabrics are significantly reduced, and other basic properties are also somewhat diminished.

[0125] It should be noted that the above embodiments are merely some preferred embodiments of the present invention, and not all embodiments. Obviously, based on the above embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

Claims

1. A medical natural antibacterial and antiviral and mildew-proof wet nonwoven fabric, characterized by comprising: a natural fiber web; and a natural antibacterial and antiviral and mildew-proof agent. It is prepared by the following raw materials: polyethylene terephthalate long fiber, polyethylene terephthalate short fiber, vinylon fiber, and natural antibacterial and antiviral ultraviolet slow-release microcapsule glue solution; the preparation method of the natural antibacterial and antiviral ultraviolet slow-release microcapsule glue solution is: (1) Preparation of surface-modified nanomaterials: blend nanomaterial powder and dispersant at a mass ratio of (5-50):1, then add to a nanoball mill for grinding to uniform dispersion, to prepare surface-modified nanomaterials; (2) Extraction of natural antibacterial and antiviral components: grind Chinese herbal medicine into powder, immerse the solid powder in distilled water, and heat distill at 80-100℃, the distillate being a Chinese herbal medicine water extract; then add 3-5 times the weight of a 50-60% mass fraction ethanol solution to the residue and reflux extract 3 times, using ultrasonic assisted reflux extraction with a power of 80-100W and a frequency of 20-50KHz, filter, centrifuge and recover ethanol under reduced pressure to obtain a Chinese herbal medicine alcohol extract, mix the water extract and alcohol extract evenly to obtain natural antibacterial and antiviral components; (3) Preparation of natural antibacterial and antiviral ultraviolet slow-release microcapsule glue solution by improved multiple emulsion method: disperse the surface-modified nanomaterials and natural antibacterial and antiviral components in solvent ethyl acetate, emulsify to obtain a primary emulsion; mix collagen, melamine, crosslinking agent and water at a mass ratio of (10):(0.5-2):(0.1-2):(100) to obtain a mixed aqueous solution; disperse the primary emulsion into the mixed aqueous solution, add Lewis acid and emulsifying dispersant, continuously stir and heat to volatilize the solvent, to obtain a natural antibacterial and antiviral ultraviolet slow-release microcapsule glue solution suitable for wet non-woven fabric; The mass ratio of the polyethylene terephthalate long fiber, polyethylene terephthalate short fiber, vinylon fiber, and natural antibacterial and antiviral ultraviolet slow-release microcapsule glue solution is 3:1:3:

3.

2. The medical natural antibacterial and antiviral and mildew-proof wet nonwoven fabric according to claim 1, wherein The length of the polyethylene terephthalate long fiber is 11-14mm, and the length of the polyethylene terephthalate short fiber is 5-8mm.

3. The medical natural antibacterial and antiviral and mildew-proof wet nonwoven fabric according to claim 1, wherein In step (1), the nanomaterial powder is one or more of graphene, zinc oxide or zirconium oxide, and the dispersant is one or more of polyoxyethylene octylphenol ether, fatty alcohol polyoxyethylene ether, and castor oil polyoxyethylene ether.

4. The medical natural antibacterial and antiviral and mildew-proof wet nonwoven fabric according to claim 1, wherein In step (2), the Chinese herbal medicine is one or more of isatis root, honeysuckle, dandelion, wormwood, and neem leaves.

5. The medical natural antibacterial and antiviral and mildew-proof wet nonwoven fabric according to claim 1, wherein In step (3), the crosslinking agent is an organic compound containing an aldehyde group -CHO in an amount of not less than 2, and the emulsifying dispersant is a non-ionic surfactant.

6. The medical natural antibacterial and antiviral and mildew-proof wet nonwoven fabric according to claim 1, wherein In step (3), the amount of surface-modified nanomaterials, natural antibacterial and antiviral components, and ethyl acetate is 1g:10mL:50mL; the volume ratio of the primary emulsion to the mixed aqueous solution is 1:1; and the amount of Lewis acid and emulsifying dispersant added is 0.1%-2% of the total mass of the primary emulsion and the mixed aqueous solution.

7. A method for preparing the medical natural antibacterial and antiviral and mildew-proof wet nonwoven fabric according to any one of claims 1 to 6, characterized in that, It comprises the following preparation steps: (1) Preparation of natural antibacterial and antiviral ultraviolet slow-release microcapsule glue solution; (2) proportionally disperse raw material polyethylene terephthalate long fibers, polyethylene terephthalate short fibers, vinylon fibers, natural antibacterial and antiviral ultraviolet slow-release microcapsule glue in a raw material tank by ultrasonic dispersion, and form a network and solidify in a wet non-woven fabric production line, the prepared wet non-woven fabric is subjected to washing, ultrasonic impurity removal and defect removal treatment, and then is subjected to heat drawing and setting treatment, to obtain the medical wet non-woven fabric with natural antibacterial and antiviral mildew resistance.

8. The use of the medical natural antibacterial and antiviral and mildew-proof wet nonwoven fabric according to any one of claims 1 to 6, characterized in that, Use as air filtration material, catalyst carrier or adsorption material.

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