Waterproof and breathable fabric and preparation method thereof

Abstract

This invention discloses a waterproof and breathable fabric and its preparation method, belonging to the field of functional fabric technology. The fabric comprises an inner layer, a middle layer, and an outer layer. Bamboo fiber and cotton fiber are woven into a fabric to form the inner layer; nylon fiber is woven into a fabric to form the outer layer. The inner layer, a modified polytetrafluoroethylene (PTFE) film, and the outer layer are stacked sequentially and hot-pressed together using polyamide hot melt adhesive. After washing and drying, the fabric is obtained. The fabric of this invention has a three-layer composite structure. The inner layer is skin-friendly, antibacterial, breathable, and moisture-permeable; the outer layer is wear-resistant, corrosion-resistant, highly elastic, and strong; and the middle layer is a modified PTFE film. It is not only waterproof, breathable, and moisture-permeable but also possesses highly efficient and safe antibacterial properties. Therefore, the obtained fabric is not only waterproof and breathable but also antibacterial, skin-friendly, durable, and wear-resistant, making it of significant application value in outdoor sportswear and other fields.

Description

Technical Field

[0001] This invention belongs to the field of functional fabric technology, specifically relating to a waterproof and breathable fabric and its preparation method. Background Technology

[0002] Functional fabrics refer to fabrics that, in addition to their basic functional properties, also possess one or more of the following effects: antibacterial, anti-mite, anti-mildew, antiviral, mosquito-repellent, moth-repellent, flame-retardant, wrinkle-resistant and non-iron-wrapping, waterproof, UV-resistant, electromagnetic radiation-resistant, fragrant, magnetic therapy, infrared therapy, negative ion health care, etc.

[0003] Waterproof fabrics are in high demand in fields such as outdoor sportswear, casual wear, and fire protection. Most waterproof fabrics currently have a waterproof layer coated on the surface of the woven layer to give the fabric a waterproof effect. However, the waterproof layer itself is an impermeable coating, which makes the airflow between the inside and outside of the fabric poor, resulting in insufficient breathability. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a waterproof and breathable fabric and its preparation method.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A waterproof and breathable fabric includes an inner layer, a middle layer and an outer layer, which are bonded together by hot pressing with polyamide hot melt adhesive;

[0007] The inner layer is in direct contact with the human body. It is made of cotton fiber and bamboo fiber blended in a ratio of 10:8-12. Cotton fiber and bamboo fiber have high skin-friendly, breathable and moisture-wicking properties. Using the blend of the two as the inner layer makes the fabric skin-friendly and breathable and moisture-wicking. In addition, bamboo fiber has natural antibacterial, bacteriostatic and mite-removing effects, which can improve the defect of breathable fabrics that are prone to bacterial growth.

[0008] The outer layer is made of nylon fiber, which has high abrasion resistance, elasticity and corrosion resistance. As the outer layer of the fabric, it can extend the service life of the fabric.

[0009] The intermediate layer is a modified polytetrafluoroethylene (PTFE) membrane, which is prepared through the following steps:

[0010] S1. Add 2-methyl-4-carboxypyridine, triethylamine, and acetonitrile to a three-necked flask equipped with a stirrer, a reflux condenser, and a nitrogen delivery tube. Purge with nitrogen for 10 minutes, then add an acetonitrile solution of chitosan oligosaccharide and DIC (N,N-diisopropylcarbodiimide, a dehydrating agent). After the addition is complete, stir the reaction at room temperature under N2 protection for 3 hours. After the reaction is complete, remove most of the solvent (acetonitrile) by rotary evaporation, then separate by column chromatography (eluent is methanol / chloroform system), concentrate under reduced pressure to obtain intermediate product 1; the ratio of 2-methyl-4-carboxypyridine, triethylamine, chitosan oligosaccharide, and DIC is 0.1 mol: 10.1 g: 0.1 mol: 12.6 g.

[0011] Under the action of triethylamine and DIC, the -COOH on the 2-methyl-4-carboxypyridine molecule undergoes an amidation reaction with the -NH2 on the chitosan oligosaccharide molecule. By controlling the molar ratio of the two to 1:1, only one -NH2 of the chitosan oligosaccharide participates in the reaction, and intermediate product 1 is obtained, that is, a pyridine ring is introduced on the chitosan oligosaccharide molecule.

[0012] S2. Add intermediate product 1 and acetone to a three-necked flask equipped with a stirrer, stir to mix evenly and maintain the temperature at 30°C. While stirring, mix 1-chlorodecane, sodium carbonate and acetone and slowly add them dropwise to the three-necked flask using a constant pressure dropping funnel. After the addition is complete, continue stirring at 30°C for 3 hours. After the reaction is complete, remove the solvent (acetone) by rotary evaporation to obtain intermediate product 2. The ratio of intermediate product 1, 1-chlorodecane and sodium carbonate is 0.1 mol: 0.1 mol: 10.6 g.

[0013] Under the action of sodium carbonate, -NH2 on intermediate product 1 molecule and -Cl on 1-chlorodecane molecule undergo nucleophilic substitution reaction. By controlling the molar ratio of the two to 1:1, a monosubstitution reaction occurs to obtain intermediate product 2, which introduces a long fatty carbon chain onto chitosan oligosaccharide.

[0014] S3. Add intermediate product 2 and acetonitrile to a three-necked flask equipped with a stirrer. After stirring until dissolved, add iodomethane and stir the reaction at room temperature for 16 hours. Stop the reaction, concentrate under reduced pressure (to remove acetonitrile), add deionized water, and pass through anion exchange apparatus (Cl). - The modified chitosan oligosaccharide was obtained by ion exchange resin exchange and concentration under reduced pressure; the molar ratio of intermediate product 2 to iodomethane was 1:1.2.

[0015] The pyridine ring undergoes an alkylation reaction with iodomethane to give a quaternized product, thereby introducing a pyridine quaternary ammonium salt onto the surface of the chitosan oligosaccharide;

[0016] S4. Polytetrafluoroethylene dispersion resin, modified chitosan oligosaccharide, and acrylate rubber are mixed in proportion, and then premixed, extruded, calendered, biaxially stretched, and heat-set to obtain a modified polytetrafluoroethylene film.

[0017] Furthermore, by weight, the modified polytetrafluoroethylene membrane comprises the following raw materials: 100 parts of polytetrafluoroethylene dispersion resin, 6-9 parts of modified chitosan oligosaccharide, and 15-20 parts of acrylate rubber.

[0018] Polytetrafluoroethylene (PTFE) membrane is a flexible and elastic microporous material that is breathable but waterproof. Using it as a middle layer in fabrics can effectively achieve waterproof, breathable, and moisture-wicking effects. However, PTFE has a weak antibacterial property, making it susceptible to microbial contamination during the wicking process. The inner layer contains bamboo fiber, which has some antibacterial properties, while the outer layer is made of nylon, which is less prone to microbial contamination. Therefore, antibacterial modification of the PTFE membrane in the middle layer is necessary. This invention involves adding modified chitosan oligosaccharides to the PTFE membrane raw materials. Chitosan oligosaccharides themselves have high bioactivity and good antibacterial activity, but compatibility with PTFE dispersion resin is a concern. Poor dispersion makes it difficult to achieve uniform distribution. By modifying chitosan oligosaccharides and introducing long aliphatic carbon chains on their surface, these long aliphatic chains, with their high flexibility, not only become compatible with PTFE molecular chains but also flexibly insert themselves between polymer chains. This improves the interfacial compatibility between chitosan oligosaccharides and the resin matrix, promoting dispersion. In addition, quaternary ammonium salts are grafted onto the surface of chitosan oligosaccharides, which are highly effective and safe antibacterial components with different antibacterial mechanisms than chitosan oligosaccharides. Therefore, a synergistic effect is produced, further enhancing the antibacterial properties of the modified chitosan oligosaccharides and achieving high efficiency with low quantity. The resulting modified PTFE film is not only waterproof, breathable, and moisture-permeable but also possesses highly effective and safe antibacterial properties, improving the practicality and comfort of the fabric.

[0019] The preparation method of the above-mentioned waterproof and breathable fabric is as follows:

[0020] Bamboo fiber and cotton fiber are woven into fabric to form the inner layer of the fabric; nylon fiber is woven into fabric to form the outer layer of the fabric.

[0021] The inner layer, modified polytetrafluoroethylene film, and outer layer are stacked sequentially, and then hot-pressed together with polyamide hot melt adhesive. After washing and drying, the fabric is obtained.

[0022] The beneficial effects of this invention are:

[0023] The fabric of this invention has a three-layer composite structure. The inner layer is skin-friendly, antibacterial, breathable and moisture-wicking, the outer layer is wear-resistant, corrosion-resistant, highly elastic and strong, and the middle layer is a modified polytetrafluoroethylene film. It is not only waterproof, breathable and moisture-wicking, but also has highly efficient and safe antibacterial properties. Therefore, the obtained fabric is not only waterproof and breathable, but also antibacterial, skin-friendly, durable and wear-resistant, and has important application value in outdoor sportswear and other fields. Detailed Implementation

[0024] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. 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 of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0025] Example 1

[0026] Preparation of modified polytetrafluoroethylene membrane:

[0027] S1. Add 0.1 mol of 2-methyl-4-carboxypyridine, 10.1 g of triethylamine and 200 mL of acetonitrile to a three-necked flask equipped with a stirrer, a reflux condenser and a nitrogen delivery tube. Purge with nitrogen for 10 min, then add 50 mL of acetonitrile solution containing 0.1 mol of chitosan oligosaccharide and 12.6 g of DIC. After the addition is complete, stir the reaction at room temperature and under N2 protection for 3 h. After the reaction is complete, remove most of the solvent (acetonitrile) by rotary evaporation, then separate by column chromatography (elution buffer is methanol / chloroform system), concentrate under reduced pressure to obtain intermediate product 1.

[0028] S2. Add 0.1 mol of intermediate product 1 and 200 mL of acetone to a three-necked flask equipped with a stirrer. Stir to mix evenly and maintain the temperature at 30°C. While stirring, mix 0.1 mol of 1-chlorodecane, 10.6 g of sodium carbonate and 50 mL of acetone and slowly add the mixture dropwise to the three-necked flask using a constant pressure dropping funnel. After the addition is complete, continue stirring at 30°C for 3 hours. After the reaction is complete, remove the solvent (acetone) by rotary evaporation to obtain intermediate product 2.

[0029] S3. Add 0.1 mol of intermediate product 2 and 200 mL of acetonitrile to a three-necked flask equipped with a stirrer. After stirring and dissolving, add 0.12 mol of iodomethane. Stir the reaction at room temperature for 16 h, then stop the reaction. Concentrate under reduced pressure (to remove acetonitrile), add deionized water, and pass through anion exchange apparatus (Cl). - The modified chitosan oligosaccharide was obtained by ion exchange with a resin and concentration under reduced pressure.

[0030] S4. After mixing 1 kg of polytetrafluoroethylene dispersion resin, 60 g of modified chitosan oligosaccharide, and 150 g of acrylate rubber, the mixture is premixed, extruded, calendered, biaxially stretched, and heat-set to obtain a modified polytetrafluoroethylene film.

[0031] Example 2

[0032] Preparation of modified polytetrafluoroethylene membrane:

[0033] S1. Add 0.1 mol of 2-methyl-4-carboxypyridine, 10.1 g of triethylamine and 200 mL of acetonitrile to a three-necked flask equipped with a stirrer, a reflux condenser and a nitrogen delivery tube. Purge with nitrogen for 10 min, then add 50 mL of acetonitrile solution containing 0.1 mol of chitosan oligosaccharide and 12.6 g of DIC. After the addition is complete, stir the reaction at room temperature and under N2 protection for 3 h. After the reaction is complete, remove most of the solvent (acetonitrile) by rotary evaporation, then separate by column chromatography (elution buffer is methanol / chloroform system), concentrate under reduced pressure to obtain intermediate product 1.

[0034] S2. Add 0.1 mol of intermediate product 1 and 200 mL of acetone to a three-necked flask equipped with a stirrer. Stir to mix evenly and maintain the temperature at 30°C. While stirring, mix 0.1 mol of 1-chlorodecane, 10.6 g of sodium carbonate and 50 mL of acetone and slowly add the mixture dropwise to the three-necked flask using a constant pressure dropping funnel. After the addition is complete, continue stirring at 30°C for 3 hours. After the reaction is complete, remove the solvent (acetone) by rotary evaporation to obtain intermediate product 2.

[0035] S3. Add 0.1 mol of intermediate product 2 and 200 mL of acetonitrile to a three-necked flask equipped with a stirrer. After stirring and dissolving, add 0.12 mol of iodomethane. Stir the reaction at room temperature for 16 h, then stop the reaction. Concentrate under reduced pressure (to remove acetonitrile), add deionized water, and pass through anion exchange apparatus (Cl). - The modified chitosan oligosaccharide was obtained by ion exchange with a resin and concentration under reduced pressure.

[0036] S4. After mixing 1 kg of polytetrafluoroethylene dispersion resin, 75 g of modified chitosan oligosaccharide, and 175 g of acrylate rubber, the mixture is premixed, extruded, calendered, biaxially stretched, and heat-set to obtain a modified polytetrafluoroethylene film.

[0037] Example 3

[0038] Preparation of modified polytetrafluoroethylene membrane:

[0039] S1. Add 0.1 mol of 2-methyl-4-carboxypyridine, 10.1 g of triethylamine and 200 mL of acetonitrile to a three-necked flask equipped with a stirrer, a reflux condenser and a nitrogen delivery tube. Purge with nitrogen for 10 min, then add 50 mL of acetonitrile solution containing 0.1 mol of chitosan oligosaccharide and 12.6 g of DIC. After the addition is complete, stir the reaction at room temperature and under N2 protection for 3 h. After the reaction is complete, remove most of the solvent (acetonitrile) by rotary evaporation, then separate by column chromatography (elution buffer is methanol / chloroform system), concentrate under reduced pressure to obtain intermediate product 1.

[0040] S2. Add 0.1 mol of intermediate product 1 and 200 mL of acetone to a three-necked flask equipped with a stirrer. Stir to mix evenly and maintain the temperature at 30°C. While stirring, mix 0.1 mol of 1-chlorodecane, 10.6 g of sodium carbonate and 50 mL of acetone and slowly add the mixture dropwise to the three-necked flask using a constant pressure dropping funnel. After the addition is complete, continue stirring at 30°C for 3 hours. After the reaction is complete, remove the solvent (acetone) by rotary evaporation to obtain intermediate product 2.

[0041] S3. Add 0.1 mol of intermediate product 2 and 200 mL of acetonitrile to a three-necked flask equipped with a stirrer. After stirring and dissolving, add 0.12 mol of iodomethane. Stir the reaction at room temperature for 16 h, then stop the reaction. Concentrate under reduced pressure (to remove acetonitrile), add deionized water, and pass through anion exchange apparatus (Cl). - The modified chitosan oligosaccharide was obtained by ion exchange with a resin and concentration under reduced pressure.

[0042] S4. After mixing 1 kg of polytetrafluoroethylene dispersion resin, 90 g of modified chitosan oligosaccharide, and 200 g of acrylate rubber, the mixture is premixed, extruded, calendered, biaxially stretched, and heat-set to obtain a modified polytetrafluoroethylene film.

[0043] Comparative Example 1

[0044] 1 kg of polytetrafluoroethylene dispersion resin, 60 g of chitosan oligosaccharide, and 150 g of acrylate rubber were compounded and then premixed, extruded, calendered, biaxially stretched, and heat-set to obtain a polytetrafluoroethylene film.

[0045] Example 4

[0046] Preparation of waterproof and breathable fabrics:

[0047] Bamboo fiber and cotton fiber are woven into a fabric at a mass ratio of 8:10 to form the inner layer of the fabric; nylon fiber is woven into a fabric to form the outer layer of the fabric.

[0048] The inner layer, the modified polytetrafluoroethylene film prepared in Example 1, and the outer layer are stacked sequentially, and then hot-pressed together with polyamide hot melt adhesive. After cleaning and drying, the fabric is obtained.

[0049] Example 5

[0050] Preparation of waterproof and breathable fabrics:

[0051] Bamboo fiber and cotton fiber are woven into a fabric in a 10:10 mass ratio to form the inner layer of the fabric; nylon fiber is woven into a fabric to form the outer layer of the fabric.

[0052] The inner layer, the modified polytetrafluoroethylene film prepared in Example 2, and the outer layer are stacked sequentially, and then hot-pressed together with polyamide hot melt adhesive. After cleaning and drying, the fabric is obtained.

[0053] Example 6

[0054] Preparation of waterproof and breathable fabrics:

[0055] Bamboo fiber and cotton fiber are woven into a fabric at a mass ratio of 12:10 to form the inner layer of the fabric; nylon fiber is woven into a fabric to form the outer layer of the fabric.

[0056] The inner layer, the modified polytetrafluoroethylene film prepared in Example 3, and the outer layer are stacked sequentially, and then hot-pressed together with polyamide hot melt adhesive. After cleaning and drying, the fabric is obtained.

[0057] Comparative Example 2

[0058] The fabric obtained by replacing the modified polytetrafluoroethylene film in Example 4 with the polytetrafluoroethylene film prepared in the comparative example.

[0059] Comparative Example 3

[0060] The fabric obtained by replacing the modified polytetrafluoroethylene film in Example 4 with ordinary polytetrafluoroethylene film.

[0061] The fabrics obtained in Examples 4-6 and Comparative Examples 2-3 were cut into test samples and subjected to the following performance tests:

[0062] The moisture permeability was tested according to GB / T 12704-2009 "Textiles - Test methods for moisture permeability - Part 1: Moisture absorption method";

[0063] The air permeability was tested according to GB / T 5453-1997 "Textiles - Determination of air permeability of fabrics";

[0064] The breaking strength was tested according to GB / T 3923.1-2013 "Textiles - Tensile Properties of Fabrics - Part 1: Determination of Breaking Strength (Strip Method)";

[0065] Water resistance was tested according to GB / T 4745-2012 "Test and Evaluation of Water Resistance of Textiles - Water Immersion Method";

[0066] The antibacterial rate (%) of the fabric was tested according to GB / T 20944.2-2007 "Evaluation of antimicrobial properties of textiles - Part 2: Absorption method" (the tested bacteria were Escherichia coli).

[0067] The measured results are shown in the table below:

[0068] Example 4 Example 5 Example 6 Comparative Example 2 Comparative Example 3 <![CDATA[Water vapor permeability / g·m -2 ·24h -1 > 6230 6450 6570 6150 6355 <![CDATA[Air permeability / mm·s -1 > 1.3 1.4 1.4 1.3 1.3 Meridional fracture strength / N 1050 1120 1170 910 960 latitudinal fracture strength / N 720 765 790 620 670 Surface water repellency / grade 4-5 4-5 4-5 4-5 4-5 Antibacterial rate / % 94.2 95.4 96.1 91.2 86.5

[0069] As can be seen from the data in the table above, the fabric obtained by the present invention has high breathability and moisture permeability as well as good waterproofness. In addition, it also has the advantages of high strength and good antibacterial properties. Combined with the data of Comparative Example 2 and Comparative Example 3, it can be seen that after modification, chitosan oligosaccharide can be evenly dispersed, which can not only improve the antibacterial properties of polytetrafluoroethylene film, but also improve mechanical strength to a certain extent.

[0070] In the description of this specification, the references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0071] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. A waterproof and breathable fabric comprising an inner layer, a middle layer and an outer layer, characterized in that, The intermediate layer is a modified polytetrafluoroethylene (PTFE) membrane, which is prepared by the following steps: S1. Add 2-methyl-4-carboxypyridine, triethylamine and acetonitrile to a three-necked flask equipped with a stirrer, a reflux condenser and a nitrogen delivery tube. Purge with nitrogen for 10 min, then add chitosan oligosaccharide acetonitrile solution and DIC. After addition, stir the reaction at room temperature and under N2 protection for 3 h. After the reaction is complete, remove most of the solvent by rotary evaporation, then separate by column chromatography and concentrate under reduced pressure to obtain intermediate product 1. S2. Add intermediate product 1 and acetone to a three-necked flask equipped with a stirrer, stir to mix evenly and keep the temperature at 30°C. Mix 1-chlorodecane, sodium carbonate and acetone under stirring and slowly drop them into the three-necked flask using a constant pressure dropping funnel. After the addition is complete, continue to stir the reaction at 30°C for 3 hours. After the reaction is complete, remove the solvent by rotary evaporation to obtain intermediate product 2. S3. Add intermediate product 2 and acetonitrile to a three-necked flask equipped with a stirrer. After stirring and dissolving, add iodomethane and stir at room temperature for 16 hours. Stop the reaction, concentrate under reduced pressure, add deionized water, exchange with anion exchange resin, concentrate under reduced pressure, and obtain modified chitosan oligosaccharide. S4. Polytetrafluoroethylene dispersion resin, modified chitosan oligosaccharide, and acrylate rubber are mixed in proportion, and then premixed, extruded, calendered, biaxially stretched, and heat-set to obtain a modified polytetrafluoroethylene film.

2. The waterproof and breathable fabric according to claim 1, wherein, In step S1, the ratio of 2-methyl-4-carboxypyridine, triethylamine, chitosan oligosaccharide, and DIC is 0.1 mol: 10.1 g: 0.1 mol: 12.6 g.

3. The waterproof and breathable fabric of claim 1, wherein, In step S2, the ratio of intermediate product 1, 1-chlorodecane, and sodium carbonate is 0.1 mol: 0.1 mol: 10.6 g.

4. The waterproof and breathable fabric of claim 1, wherein, In step S3, the molar ratio of intermediate product 2 to iodomethane is 1:1.

2.

5. The waterproof and breathable fabric of claim 1, wherein, By weight, the modified polytetrafluoroethylene membrane comprises the following raw materials: 100 parts polytetrafluoroethylene dispersion resin, 6-9 parts modified chitosan oligosaccharide, and 15-20 parts acrylate rubber.

6. The waterproof and breathable fabric of claim 1, wherein, The inner layer is made of cotton fiber and bamboo fiber blended in a mass ratio of 10:8-12.

7. The waterproof and breathable fabric according to claim 1, characterized in that, The outer layer is made of nylon fiber.

8. The method for preparing a waterproof and breathable fabric according to claim 1, characterized in that, Specifically as follows: Bamboo fiber and cotton fiber are woven into fabric to form the inner layer of the fabric; nylon fiber is woven into fabric to form the outer layer of the fabric. The inner layer, modified polytetrafluoroethylene film, and outer layer are stacked sequentially, and then hot-pressed together with polyamide hot melt adhesive. After washing and drying, the fabric is obtained.