Bio-based wear-resistant fabric and preparation method thereof

Abstract

The invention discloses a bio-based wear-resistant fabric and a preparation method thereof, and relates to the technical field of textile, the bio-based wear-resistant fabric comprises a bio-based nylon fabric layer, a polytetrafluoroethylene electrostatic spinning nano-film layer and nylon warp-knitted ground yarn which are arranged in sequence; the teflon electrostatic spinning nano film layer is a middle layer, and the bio-based nylon fabric layer and the nylon warp-knitted ground yarn are respectively attached to two sides of the teflon electrostatic spinning nano film layer by using bio-based hot melt adhesive; hydrophobic silicon dioxide nanoparticles modified by a silane coupling agent are respectively added into the bio-based hot melt adhesive and the polytetrafluoroethylene electrostatic spinning nano film layer; wherein the silicon dioxide nanoparticles added in the nano film layer are also subjected to modification treatment to form a core-shell structure; the bio-based wear-resistant fabric with high waterproof and moisture permeable performance, good wear resistance and difficult-to-block gaps is prepared by combining introduction and modification treatment of hydrophobic silicon dioxide nanoparticles, the overall performance of the fabric is improved, and the service life of the fabric is prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of textiles, and in particular to a bio-based wear-resistant fabric and a preparation method thereof. Background Art

[0002] Fabric is the material used to make clothing. As one of the three elements of clothing, fabric can not only interpret the style and characteristics of clothing, but also directly influence the color and shape of clothing. Among them, functional fabric refers to fabric with certain special properties and uses, such as waterproof, windproof, breathable, moisture permeable, warm, oil-proof, easy to clean, anti-bacteria and deodorizing, UV protection, anti-static, radiation protection, flame retardant, high temperature resistance, acid and alkali resistance, etc. The functional fabrics on the market are mainly clothing fabrics, mostly used in outdoor sportswear and high-end casual wear.

[0003] With the increasing global awareness of sustainable development and environmental protection, the replacement of traditional petroleum-based materials has become a research hotspot. Bio-based materials, which are derived from renewable resources and have environmentally friendly and degradable characteristics, have gradually become an important direction for the development of new materials; bio-based materials are new materials that use renewable materials such as straw and other agricultural and forestry waste, biogas, biodiesel, bioplastics, etc. as raw materials for biological, physical or chemical treatment. The environmental protection, recycling and renewable characteristics of biological and material materials meet the contemporary requirements for the ecological environment, and therefore have a good market development prospect.

[0004] For example, the Chinese patent with application number CN202210935077.2, a highly permeable bio-based nylon fabric and its preparation method, discloses a highly permeable bio-based nylon fabric, comprising: a bio-based nylon fabric layer, a PTFE electrospun nano-membrane layer and a nylon warp-knitted bottom yarn arranged in sequence, wherein the bio-based nylon fabric layer is selected from one or more of bio-based nylon 56, bio-based nylon 66 or bio-based nylon 1010. The highly permeable bio-based nylon fabric uses a bio-based nylon fabric raw material obtained by microbial fermentation and purification of agricultural, forestry and waste. The bio-based nylon fabric is not only light and wear-resistant, but also human-friendly, and can realize resource recycling. At the same time, the polytetrafluoroethylene (PTFE) electrospun nano-membrane is not only strong and chemically resistant, but also has nano-scale pores with high waterproof, high permeability and breathability, and can be widely used in clothing for extreme environments such as leisure sports or outdoor adventures.

[0005] The above scheme optimizes the void structure by stretching the PTFE membrane, which has advantages in waterproofness and moisture permeability. However, hot melt adhesive can easily penetrate into the voids of the PTFE membrane during high-temperature bonding, blocking the moisture permeability channel and affecting long-term performance. It also has insufficient wear resistance, is easy to wear, and has a short service life. Summary of the invention

[0006] The embodiments of the present application provide a bio-based wear-resistant fabric and a preparation method thereof, thereby solving the problems of insufficient waterproof and moisture permeability, insufficient wear resistance, gap clogging and insufficient interface bonding strength in the prior art. By adopting a bio-based nylon fabric layer, a PTFE electrospun nanomembrane layer and a nylon warp knitted base yarn composite structure, combined with the introduction and modification of hydrophobic silica nanoparticles, a bio-based wear-resistant fabric with high waterproof and moisture permeability, good wear resistance and non-easy gap clogging is prepared, thereby improving the overall performance and service life of the fabric.

[0007] The embodiment of the present application provides a bio-based wear-resistant fabric, comprising a bio-based nylon fabric layer, a polytetrafluoroethylene electrospun nano-membrane layer and a nylon warp-knitted base yarn arranged in sequence; The polytetrafluoroethylene electrospun nano-membrane layer is the middle layer, and the bio-based nylon fabric layer and the nylon warp-knitted bottom yarn are respectively attached to the two sides of the polytetrafluoroethylene electrospun nano-membrane layer using bio-based hot melt adhesive; Hydrophobic silica nanoparticles modified by silane coupling agent are added to the bio-based hot melt adhesive and polytetrafluoroethylene electrospun nanofilm layer respectively; Among them, the silicon dioxide nanoparticles added to the polytetrafluoroethylene electrospun nanomembrane layer are also coated with graphene oxide to form a core-shell structure.

[0008] Furthermore, the particle size of the silicon dioxide nanoparticles is 10-50 nm.

[0009] Furthermore, the amount of silicon dioxide nanoparticles added to the bio-based hot melt adhesive is 5-10% of the total mass of the bio-based hot melt adhesive, preferably 8%.

[0010] Furthermore, the silicon dioxide nanoparticles are pretreated before being added to the bio-based hot melt adhesive, and the specific steps are as follows: Premixing: premix the hydrophobic silica nanoparticles with the bio-based hot melt adhesive and stir at a low speed; Ultrasonic dispersion: The mixture is dispersed by ultrasound; Degassing by standing: After dispersion, let it stand to eliminate bubbles in the colloid.

[0011] Furthermore, the concentration of silicon dioxide nanoparticles added to the polytetrafluoroethylene electrospun nanofilm layer is 1-3wt%, preferably 2wt%.

[0012] Furthermore, the core layer of the core-shell structure is hydrophobic silica nanoparticles, and the shell layer is graphene oxide.

[0013] Furthermore, the mass ratio of silica nanoparticles to graphene oxide in the core-shell structure is 5:1.

[0014] Further, the preparation of the core-shell structure comprises the following specific steps: Hydrophobic modification of silica nanoparticles: disperse silica nanoparticles in ethanol, add silane coupling agent, stir, centrifuge and wash, and then dry; Graphene oxide coating: hydrophobically modified silica nanoparticles and graphene oxide were added to deionized water and ultrasonically dispersed; A cross-linking agent is added, the mixture is centrifuged and freeze-dried to obtain a core-shell structure.

[0015] Furthermore, the silica nanoparticles in the bio-based hot melt adhesive have different particle sizes from the silica nanoparticles added to the polytetrafluoroethylene electrospun nanofilm layer, wherein the silica nanoparticles in the bio-based hot melt adhesive have a particle size of 10-30 nm, and the silica nanoparticles in the polytetrafluoroethylene electrospun nanofilm layer have a particle size of 50-80 nm.

[0016] A method for preparing a bio-based wear-resistant fabric, the specific steps are: S1. Preparation of bio-based nylon fabric layer: one or more of bio-based nylon 56, bio-based nylon 66 or bio-based nylon 1010 are subjected to fabric joining, desizing, dyeing, drying, intermediate inspection, shaping and final inspection to obtain a bio-based nylon fabric layer; S2. Preparation of polytetrafluoroethylene electrospun nanofilm layer: a polytetrafluoroethylene aqueous emulsion, a polyvidone aqueous solution and an antistatic additive are blended to obtain an electrospinning solution, and the electrospinning solution is prepared by an electrospinning process. The prepared polytetrafluoroethylene electrospun nanofilm layer is stretched in a single direction for the first time, and allowed to stand for finalization; and then stretched for a second time in the direction of the first stretching; S3, gluing and laminating: placing the stretched polytetrafluoroethylene electrospun nano-membrane layer on a laminating machine, heating and melting the pretreated bio-based hot melt adhesive and evenly coating it on the surface of the membrane layer, and laminating the bio-based nylon fabric layer and the nylon warp knitted base yarn with the polytetrafluoroethylene electrospun nano-membrane layer coated with the hot melt adhesive; S4. Curing: Place the laminated bio-based wear-resistant fabric in a curing room for curing, and the fabric will be ready after curing.

[0017] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages: First, by introducing hydrophobic silica nanoparticles into bio-based hot melt adhesives, the problems of gap blockage, insufficient interface bonding, poor heat resistance and insufficient wear resistance in fabric preparation are solved, an anti-blocking protective layer is formed, and the interface bonding and fabric wear resistance are enhanced, thereby improving the overall performance and service life of the fabric. Secondly, by adding silica nanoparticles to the PTFE electrospun nanofilm layer, the problems of hot melt adhesive infiltration into the gaps, poor gap stability and insufficient wear resistance in fabric preparation are solved, which has the effects of improving gap stability, maintaining moisture permeability, enhancing anti-colloid penetration ability and improving wear resistance. The hydrophobic silica nanoparticles evenly cover the gap surface of the PTFE electrospun nanofilm through van der Waals force and surface adsorption. The size of the nanoparticles is smaller than the gap width and will not block the gap channel, but can fill the microscopic defects such as cracks or irregular edges on the gap surface. At the same time, it can form a physical barrier layer to prevent the bio-based hot melt adhesive from penetrating into the gap during the bonding process; Thirdly, by constructing a core-shell structure with hydrophobic silica nanoparticles as the core and graphene oxide as the shell, and introducing a PTFE electrospun nanomembrane layer, the problems of poor void stability, low mechanical strength, and insufficient waterproof and breathable performance were solved; void support, fiber network bonding, and interface bonding were enhanced, tear resistance, abrasion resistance, moisture permeability, and hydrophobicity were improved, and the overall performance of the fabric was improved; Fourthly, by differentially regulating the particle size of silica nanoparticles in the PTFE electrospun nanomembrane layer and the bio-based hot melt adhesive, the synergistic optimization of high moisture permeability and high waterproof bio-based nylon composite fabrics was achieved; the small-size silica nanoparticles in the PTFE membrane layer are more easily embedded in the microscopic defects of the PTFE fiber network and the surface of the voids, filling the edges of the voids and enhancing the local mechanical strength; the small particle size is not easy to block the void channels (width 200-400 nm), so it can maintain high moisture permeability; the large silica nanoparticles in the bio-based hot melt adhesive form a wider physical barrier through the steric hindrance effect, occupy more colloid flow paths, and reduce the migration of colloids into the voids through physical blocking. DETAILED DESCRIPTION

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which the present invention belongs; the terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the term "and / or" used herein includes any and all combinations of one or more related listed items.

[0019] Embodiment 1: A bio-based wear-resistant fabric, comprising: a bio-based nylon fabric layer, a polytetrafluoroethylene (PTFE) electrospun nano-membrane layer and a nylon warp-knitted base yarn arranged in sequence; The bio-based nylon fabric layer is one or more of bio-based nylon 56, bio-based nylon 66 or bio-based nylon 1010; The PTFE electrospinning nano-membrane layer is prepared by mixing an electrospinning solution obtained by mixing a PTFE aqueous emulsion, a polyvinylpyrrolidone (PVP) aqueous solution and an antistatic additive, and is prepared by an electrospinning process. The voids of the PTFE electrospinning nano-membrane layer are nanoscale, and the aspect ratio thereof is 1.5:1-3:1; The PTFE electrospun nano-membrane layer is used as the middle layer, and the bio-based nylon fabric layer and the nylon warp-knitted base yarn are respectively attached to both sides of the PTFE electrospun nano-membrane layer using a bio-based hot melt adhesive; The bio-based hot melt adhesive contains silicon dioxide nanoparticles with a particle size of 10-50 nm. The surface of the silicon dioxide nanoparticles is modified by a silane coupling agent KH-570 to form hydrophobic silicon dioxide nanoparticles. The amount of silicon dioxide nanoparticles added is 5-10% of the total mass of the bio-based hot melt adhesive. The PTFE electrospun nanofilm layer is stretched in a single direction; The gap width of the PTFE electrospun nano-membrane layer is 200-400 nanometers, and the gap length of the PTFE electrospun nano-membrane layer is 300-1200 nanometers; The preparation method of the bio-based wear-resistant fabric comprises the following specific steps: S1. Preparation of bio-based nylon fabric layer: one or more of bio-based nylon 56, bio-based nylon 66 or bio-based nylon 1010 are subjected to fabric joining, desizing, dyeing, drying, intermediate inspection, shaping and final inspection to obtain a bio-based nylon fabric layer; S11, desizing treatment: use alkaline additives, enzyme preparations and surfactants to treat at 100°C for 30 minutes to remove sizing and grease residues; Among them, the alkaline auxiliary agent is NaOH, the enzyme preparation is lipase, and the surfactant is sodium fatty alcohol polyoxyethylene ether sulfate (AES); S12, dyeing and reduction cleaning: dyeing with leveling agent and dispersant, followed by removal of floating color with reduction cleaning agent; Among them, the leveling agent is sodium alkyl sulfonate, the dispersant is sodium lignin sulfonate, and the reducing cleaning agent is sodium disulfite; S13, water-repellent treatment: Dip and roll with fluorine-free ecological waterproof agent, concentration 40g / L, liquid rate 50-80%, and form a hydrophobic layer by baking at 180℃; Among them, the main chain of the fluorine-free ecological waterproofing agent is an acrylate copolymer, specifically, methyl methacrylate / butyl methacrylate copolymer; the usage of the fluorine-free ecological waterproofing agent is 60-80g / L; S14, drying and shaping: drying at 170°C, and adjusting the width and warp and weft density through a stenter shaping machine to enhance wear resistance, thereby obtaining a bio-based nylon fabric layer; Among them, the setting temperature of the stenter setting machine is 140-180℃, and the speed is 40-60m / min; S2, preparation of PTFE electrospinning nano-membrane layer: PTFE aqueous emulsion, PVP aqueous solution and antistatic additive are blended, ultrasonicated in a water bath for 20-40 minutes, mixed to obtain an electrospinning solution, and prepared by an electrospinning process, the prepared PTFE electrospinning nano-membrane layer is stretched in a single direction for the first time, and the stretched PTFE electrospinning nano-membrane layer is allowed to stand for finalization; Then the PTFE electrospun nanofilm layer is stretched a second time in the direction of the first stretching; Among them, the concentration of PTFE aqueous emulsion is 65-85%, the concentration of PVP aqueous solution is 10-15%, the concentration of antistatic additive is 0.5-1%, the electrospinning process voltage is 17.5-21.5kV, the flow rate is 0.5-0.8mL / h, the spinning time is 2-3h, and the receiving distance is 20-25cm; the first stretching stretching amplitude is 1.3-2 times the original length, and the second stretching stretches the void aspect ratio of the PTFE electrospinning nanofilm layer to 1.5:1-3:1; S3, gluing and laminating: placing the PTFE electrospun nano-membrane layer on a laminating machine, heating and melting the pretreated bio-based hot melt adhesive and evenly coating it on the surface of the PTFE electrospun nano-membrane layer, and laminating the bio-based nylon fabric layer and the nylon warp knitted base yarn with the PTFE electrospun nano-membrane layer coated with the hot melt adhesive; Among them, the bio-based hot melt adhesive is pretreated before coating, and the pretreatment is specifically as follows: S31. Premixing: premixing the hydrophobic silica nanoparticles with the bio-based hot melt adhesive at 40-60° C. and stirring at a low speed of 200-400 rpm for 10-15 minutes; S32. Ultrasonic dispersion: The mixture was placed in an ultrasonic disperser at a power of 300 W and a temperature of 25-40°C for 40 minutes to ensure that the nanoparticles were evenly dispersed; S33. Standing degassing: After dispersion, stand for 12-24 hours to eliminate bubbles in the colloid and avoid defects during coating; The heating temperature of the bio-based hot melt adhesive is 150-170°C, the viscosity is 4500-6500mPa.s, the dispensing amount is 6-8g, and the nylon warp knitting base yarn is one of 15D, 20D or 30D; S4, maturation: placing the laminated bio-based wear-resistant fabric in a maturation room for maturation; The aging temperature is 40-50°C, the humidity is 70-90%, and the aging time is 36-48 hours.

[0020] Experiments were conducted on the above technical solution, and the experimental parameters were specifically as follows: S1, preparation of bio-based nylon fabric layer; S11, desizing treatment: NaOH concentration: 5% (w / v), lipase concentration: 2% (w / v), surfactant (AES) concentration: 1% (w / v), temperature: 100°C, time: 30 minutes; S12, dyeing and reduction cleaning: the concentration of the leveling agent sodium alkyl sulfonate is 1.5% (owf), the concentration of the dispersant sodium lignin sulfonate is 2% (owf), the concentration of the reduction cleaning agent sodium disulfite is 3 g / L, the temperature is 60°C, and the time is 15 minutes; S13, water-repellent treatment: fluorine-free water-repellent concentration: 70 g / L, padding liquid rate: 65%, baking temperature: 180°C, time: 2 minutes; S2, preparation of PTFE electrospinning nano-membrane layer; Spinning solution formula: PTFE aqueous emulsion: 75% (solid content 60%), PVP aqueous solution: 12%, antistatic additive: 0.8%; Electrospinning parameters: voltage: 20 kV, flow rate: 0.6 mL / h, receiving distance: 22 cm, spinning time: 2.5 h; Stretching process: First stretching: stretch to 1.5 times the original length, let stand for 30 minutes to set; Second stretching: adjust the gap aspect ratio to 2:1; S3, gluing and laminating; The addition amounts of silica nanoparticles were: 0, 5%, 8%, and 10%; Pretreatment parameters: premixing: 50 °C, 300 rpm stirring for 12 minutes, ultrasonic dispersion: power 300 W, temperature 30 °C, time 40 minutes, static degassing: 18 hours; The heating temperature of the bio-based hot melt adhesive is 160°C, the viscosity is 5500mPa.s, the dispensing amount is 7g, and the nylon warp knitting base yarn is 15D; S4, aging: aging temperature is 45°C, humidity is 80%, and aging time is 42 hours; The performance of the bio-based wear-resistant fabric prepared by the above scheme was tested: 1. Moisture permeability: Water vapor transmission rate test, according to GB / T 12704.1-2009; 2. Waterproofness: spray method (water repellency grade) GB / T 4745-2012; 3. Abrasion resistance: Martindale abrasion test (wool abrasive, 155g) GB / T 4802.2; The test results are shown in Table 1 below: Table 1

[0021] The technical solutions in the above embodiments of the present application have at least the following technical effects or advantages: Hydrophobic silica nanoparticles (10-50 nm in diameter) are dispersed in the colloid through the steric effect to form a physical barrier. The size of the nanoparticles (much smaller than the pore width of the PTFE membrane 200-400 nm) and their hydrophobicity allow them to cover the colloid surface, preventing the molten colloid from penetrating into the PTFE membrane pores. The repulsive effect between the particles (van der Waals force + hydrophobic effect) limits the fluidity of the colloid, avoids pore blockage, and forms an anti-blocking protective layer. In addition, the high thermal conductivity of silica nanoparticles (about 1.4 W / m·K) accelerates heat transfer. Nanoparticles act as heat conduction pathways to quickly conduct heat from the inside of the colloid, shortening the curing time (basically reducing it by more than 15%), thereby forming a heat conduction network, reducing the flow time of the colloid at high temperatures, and reducing the risk of void penetration. Third, the silanol groups (-Si-OH) on the surface of silica form hydrogen bonds with the polar groups of the colloid (such as starch hydroxyl groups), which enhance the adhesion between the adhesive layer and the PTFE membrane through chemical bonding. The formed hydrogen bond network can improve the interfacial binding energy and increase the peel strength by about 20-30%; Therefore, the fabrics made by adding silica nanoparticles to bio-based hot melt adhesives have the following advantages: High moisture permeability and waterproofness: PTFE membrane pore blockage is reduced, water vapor permeability is increased, and water repellency is improved; Improved wear resistance: The rubber layer and PTFE membrane are tightly combined, and the wear resistance is improved; Aging resistance: Silica nanoparticles enhance the heat resistance of the adhesive layer and reduce the risk of high temperature deformation; Interface stability: Hydrogen bond network resists delamination in hot and humid environments.

[0022] Silica nanoparticles enhance the adhesion between the adhesive layer and the PTFE film layer, reduce the delamination and peeling caused by friction, and thus improve the wear resistance of the fabric. The uniform dispersion of nanoparticles in the colloid makes the adhesive layer more uniform and compact, further improving the wear resistance and durability of the fabric. The introduction of silica nanoparticles effectively prevents the bio-based hot melt adhesive from clogging the gaps in the PTFE film during the curing process, thereby maintaining the high moisture permeability of the fabric. The high thermal conductivity of silica nanoparticles significantly shortens the curing time of the bio-based hot melt adhesive, reduces the risk of colloid flow at high temperatures, and improves the heat resistance of the fabric. Through the above scheme, a bio-based wear-resistant and water-repellent material was successfully developed. Its wear resistance is better than some traditional petroleum-based similar products on the market, and its water-repellent level meets international standards. It has significant environmental performance, and the carbon emissions and chemical usage in the entire production process are greatly reduced. The material itself is degradable, which is in line with the concept of circular economy.

[0023] Example 2: The above-mentioned Example 1 solves the problems of gap clogging, insufficient interface bonding, poor heat resistance and insufficient wear resistance in fabric preparation by introducing hydrophobic silica nanoparticles into the bio-based hot melt adhesive, forms an anti-clogging protective layer, enhances the interface bonding and wear resistance of the fabric, and improves the overall performance and service life of the fabric. In order to further improve the overall performance of the fabric, further improvements are made on the basis of Example 1.

[0024] Silica nanoparticles are added to the PTFE electrospun nanofilm layer, and the surface of the silica nanoparticles is modified by silane coupling agent KH-570 to form hydrophobic silica nanoparticles; the added concentration of the silica nanoparticles is 1-3wt%; The step of adding silicon dioxide nanoparticles to the PTFE electrospun nanofilm layer is specifically: Preparation of silica nanoparticle dispersion: adding 1-3 wt% of silica nanoparticles to a mixed solution of ethanol and water, and performing ultrasonic dispersion to form a dispersion; The volume ratio of ethanol to water was 7:3, the ultrasonic power was 300 W, and the time was 30 min; Addition of PTFE electrospun nano-membrane layer: immerse the PTFE electrospun nano-membrane in the dispersion for 5-10 seconds; dry at 70-90°C for 10 minutes to make the silicon dioxide nano-particles firmly adhere to the gap edge or surface defects to form a nano-scale protective layer.

[0025] Based on the experiment in Example 1 in which the amount of silicon dioxide nanoparticles added to the bio-based hot melt adhesive was 8%, the technical solution of this embodiment was used to conduct an experiment. The difference between the experiment in this embodiment and the experiment in Example 1 is that silicon dioxide nanoparticles are also added to the PTFE electrospun nanofilm layer in this embodiment, and the added concentrations of silicon dioxide nanoparticles are 0, 1wt%, 2wt%, and 3wt% respectively; The fabric prepared in this embodiment was tested for performance, and the test results are shown in Table 2 below: Table 2

[0026] The technical solutions in the above embodiments of the present application have at least the following technical effects or advantages: Hydrophobic silica nanoparticles are evenly covered on the interstitial surface of the PTFE electrospun nanomembrane (interstitial width 200-400 nm) through van der Waals force and surface adsorption. Since the size of the nanoparticles is much smaller than the interstitial width, they will not block the interstitial channels, but can fill the microscopic defects on the interstitial surface (such as cracks or irregular edges), forming a continuous physical barrier layer to prevent the bio-based hot melt adhesive from penetrating into the interstitial during the bonding process. In addition, the hydrophobic surface of the silica nanoparticles modified by silane coupling agent has a repulsive effect with the polar groups of the hot melt adhesive (such as starch hydroxyl groups). The hydrophobic nanoparticles reduce the physical contact between the colloid and the PTFE membrane by reducing the affinity between the colloid and the void surface. At the same time, the spatial arrangement between the particles forms a flow barrier, limiting the flow path of the colloid. Third, the silanol groups (-Si-OH) on the surface of silica nanoparticles form hydrogen bonds or dipole interactions with the weak polar areas on the surface of the PTFE membrane. The hydrogen bond network enhances the bonding strength between the PTFE membrane and the nanoparticles, preventing the particles from falling off. After the nanoparticles fill the surface defects of the voids, the overall mechanical stability of the PTFE membrane is improved. At the same time, the high mechanical strength of silica nanoparticles (Mohs hardness 7) enhances the local compressive resistance of the pore edges. The particles are embedded in the PTFE fibers, enhancing the stability of the pore structure and preventing collapse or deformation caused by external forces during processing or use. Therefore, the fabric with the addition of silica nanoparticles in the PTFE electrospun nanofilm layer has the following advantages: The pore structure is stable and can still effectively block liquid water and discharge sweat after long-term use; silica nanoparticles improve the heat resistance of PTFE membrane (no deformation at 180°C) and extend the life of the fabric; The pore edges are more resistant to pressure due to the filling of silica nanoparticles, which reduces fiber breakage caused by local stress concentration. The hot melt adhesive does not penetrate into the pores, the adhesive layer and the PTFE membrane interface are more evenly bonded, and the peel strength is improved (increased by about 10%), which indirectly reduces the wear caused by delamination. The stability of the pore structure of the PTFE membrane reduces the shedding of fibers and the expansion of pores during friction, and the wear resistance is further improved.

[0027] Example 3: The above-mentioned Example 2 solves the problems of hot melt adhesive infiltration into gaps, poor gap stability and insufficient wear resistance in fabric preparation by adding silica nanoparticles to the PTFE electrospun nanofilm layer, thereby improving gap stability, maintaining moisture permeability, enhancing resistance to colloid penetration and improving wear resistance, thereby improving the overall performance and service life of the fabric. In order to further improve the overall performance of the fabric, further improvements are made on the basis of Example 2.

[0028] The silicon dioxide nanoparticles added to the PTFE electrospun nanofilm layer are also modified with graphene oxide to form a core-shell structure in which the core layer is hydrophobic silicon dioxide nanoparticles and the shell layer is coated with graphene oxide; the mass ratio of silicon dioxide nanoparticles to graphene oxide is 5:1; The preparation of the core-shell structure, the specific steps are: Hydrophobic modification of silica nanoparticles: disperse silica nanoparticles in ethanol, add silane coupling agent KH-570 at 5% by mass of silica, stir at 60°C for 2 hours, centrifuge and wash, and then dry; Graphene oxide coating: hydrophobically modified silica nanoparticles and graphene oxide were added to deionized water and ultrasonically dispersed; The mass ratio of silicon dioxide nanoparticles to graphene oxide was 5:1; the ultrasonic dispersion power was 500 W and the time was 1 hour; EDC and NHS crosslinking agent were added in a molar ratio of 1:1 and reacted at room temperature for 12 hours to make graphene oxide covalently bonded to the hydroxyl groups on the surface of silica through carboxyl groups; Centrifugal separation and freeze-drying to obtain a core-shell structure; In step S2, the PTFE aqueous emulsion, the PVP aqueous solution, the core-shell structure and the antistatic additive are blended, ultrasonically dispersed in a 50° C. water bath with an ultrasonic power of 400 W for 1 hour to obtain an electrospinning solution.

[0029] The technical scheme of this embodiment is used to conduct an experiment based on the experiment in which the amount of silicon dioxide nanoparticles added to the PTFE electrospun nanofilm layer in Example 2 is 2wt%. The difference between this embodiment and the experiment in Example 2 is that the silicon dioxide nanoparticles added to the TFE electrospun nanofilm layer in this embodiment are also modified with graphene oxide to form a core layer of hydrophobic silicon dioxide nanoparticles and a shell layer of graphene oxide-coated core-shell structure; the mass ratio of silicon dioxide nanoparticles to graphene oxide is 5:1; After testing, the test results of the fabric prepared in this embodiment are shown in Table 3 below: Table 3

[0030] The technical solutions in the above embodiments of the present application have at least the following technical effects or advantages: Silica nanoparticles are introduced into the PTFE electrospun nano-membrane layer and modified to form a core-shell structure in which the core layer is hydrophobic silica nanoparticles and the shell layer is coated with graphene oxide. The core layer silica nanoparticles fill the microscopic defects on the surface of the PTFE membrane voids through hydrophobic modification to form a rigid support layer to prevent the voids from collapsing; the shell layer graphene oxide uses its two-dimensional sheet structure to embed into the PTFE fiber network to form a "skeleton support" to limit fiber slippage, improve the tear resistance of the membrane layer, and enhance the overall mechanical properties of the membrane layer. In addition, the surface functional groups (-COOH, -OH) of graphene oxide and the CF bonds of PTFE enhance the interfacial bonding through hydrogen bonds and dipole interactions, while forming chemical bonds with the polar groups of the hot melt adhesive; the hydrophobic surface of graphene oxide (contact angle of about 127°) is superimposed on PTFE (contact angle of about 118°) to form a superhydrophobic interface, which further inhibits the penetration of liquid water; Therefore, the two-dimensional sheets of graphene oxide in the core-shell structure form "pinning points" in the PTFE fiber network, limiting the slippage of the fiber during stretching or friction, dispersing external stress, and the silica core fills the weak areas on the surface of the voids to form a rigid support, reducing the risk of void deformation; the -COOH of graphene oxide forms hydrogen bonds with the CF bonds of PTFE to enhance the bonding between fibers; graphene oxide forms stable chemical bonds with polar groups such as starch hydroxyl groups of the hot melt adhesive to enhance interlayer adhesion; the bonding strength between the unmodified PTFE membrane and the hot melt adhesive layer is increased by about 30%; Therefore, after the modification, the core-shell structure formed is added to the PTFE electrospun nano-membrane layer, and the fabric has the following advantages: The tear resistance, tensile strength and other mechanical properties of the membrane layer are further improved, so that the fabric can maintain stable performance even in extreme environments. The hydrophobicity of the fabric is further enhanced, the permeability is reduced, high moisture permeability and super hydrophobicity coexist, and the interlayer bonding strength is high, so that the fabric can still maintain stable performance after multiple washing or friction; As a hard reinforcing phase, graphene oxide sheets can disperse external friction stress and reduce direct wear of PTFE fibers. At the same time, the silica core layer fills the edges of the gaps to prevent cracking of the edges of the gaps during friction. The hydrogen bond network and mechanical interlocking enhance the bonding force between fibers. The graphene oxide sheets guide the external force to be evenly dispersed along the fiber network, avoiding rapid wear caused by local stress concentration, thereby improving the wear resistance and service life of the fabric.

[0031] Example 4: The above three examples solve the problems of poor void stability, low mechanical strength and insufficient waterproof and moisture permeability by constructing a core-shell structure with hydrophobic silica nanoparticles as the core and graphene oxide as the shell, and introducing a PTFE electrospun nanomembrane layer; enhance void support, fiber network bonding and interface bonding, improve tear resistance, wear resistance, moisture permeability and hydrophobicity, and achieve an improvement in the comprehensive performance of the fabric. In order to further improve the overall performance of the fabric, further improvements are made on the basis of Example 3.

[0032] The silica nanoparticles in the bio-based hot melt adhesive have different particle sizes from the silica nanoparticles added to the PTFE electrospun nanofilm layer, wherein the silica nanoparticles in the bio-based hot melt adhesive have a particle size of 10-30 nm, and the silica nanoparticles in the PTFE electrospun nanofilm layer have a particle size of 50-80 nm.

[0033] The technical solution of this embodiment is used to conduct an experiment based on the experiment of Example 3. The difference between the experiment of this embodiment and the experiment of Example 3 is that the particle size of the silicon dioxide nanoparticles in the bio-based hot melt adhesive is 10-30nm, and the particle size of the silicon dioxide nanoparticles in the PTFE electrospun nanofilm layer is 50-80nm; After testing, the test results of the fabric prepared in this embodiment are shown in Table 4 below: Table 4

[0034] The technical solutions in the above embodiments of the present application have at least the following technical effects or advantages: By differentially regulating the particle size of the PTFE electrospun nanomembrane layer and the silica nanoparticles in the bio-based hot melt adhesive, the synergistic optimization of the highly moisture permeable and highly waterproof bio-based nylon composite fabric was achieved; the small-sized silica nanoparticles in the PTFE membrane layer are more easily embedded in the microscopic defects of the PTFE fiber network and the surface of the voids, filling the edges of the voids and enhancing the local mechanical strength; the small particle size is not easy to block the void channels (width 200-400 nm), so it can maintain high moisture permeability; the large silica nanoparticles in the bio-based hot melt adhesive form a wider physical barrier through the steric effect, occupy more colloid flow paths, and reduce the migration of colloids into the voids through physical blocking; the high specific surface area and thermal conductivity (about 1.4 W / m·K) of the large particles accelerate the curing of the colloid (curing time is shortened by about 25%), reduce the fluidity of the colloid at high temperature, and enhance the heat resistance of the adhesive layer; Silica nanoparticles of different sizes produce synergistic effects to achieve graded protection and interface complementarity. Small particles protect the void structure, and large particles block colloid penetration, thereby further improving the comprehensive performance of the fabric. At the same time, small particles in the PTFE membrane layer can enhance the fiber-fiber bonding, and large particles in the adhesive layer strengthen the fiber-adhesive layer interface. Therefore, by differentially regulating the particle size of the PTFE electrospun nanofilm layer and the silica nanoparticles in the bio-based hot melt adhesive, the fabric has the following advantages: Small-sized silica nanoparticles maintain the smoothness of the gaps, ensuring smooth water vapor penetration and maintaining high moisture permeability. Large-sized silica nanoparticles strengthen the hydrophobic interface, reduce the liquid water permeability, and improve waterproofness. The two work synergistically to further enhance the high moisture permeability and waterproofness of the fabric. Small-sized silica nanoparticles enhance the tear resistance of the PTFE membrane, repair the void structure, and improve the local mechanical strength. Large-sized silica nanoparticles disperse the stress of the adhesive layer, absorb and disperse external friction through physical cross-linking points, delay the wear of the adhesive layer, and improve the stability of the fabric.

[0035] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A bio-based wear-resistant fabric, characterized in that: It includes a bio-based nylon fabric layer, a polytetrafluoroethylene electrospun nano-membrane layer and a nylon warp-knitted base yarn arranged in sequence; The polytetrafluoroethylene electrospun nano-membrane layer is the middle layer, and the bio-based nylon fabric layer and the nylon warp-knitted bottom yarn are respectively attached to the two sides of the polytetrafluoroethylene electrospun nano-membrane layer using a bio-based hot melt adhesive; Hydrophobic silica nanoparticles modified by silane coupling agent are added to the bio-based hot melt adhesive and polytetrafluoroethylene electrospun nanofilm layer respectively; Among them, the silicon dioxide nanoparticles added to the polytetrafluoroethylene electrospun nanofilm layer are also coated with graphene oxide to form a core-shell structure.

2. The bio-based wear-resistant fabric according to claim 1, characterized in that: The particle size of silica nanoparticles is 10-50 nm.

3. The bio-based wear-resistant fabric according to claim 1, characterized in that: The amount of silica nanoparticles added to the bio-based hot melt adhesive is 5-10% of the total mass of the bio-based hot melt adhesive.

4. The bio-based wear-resistant fabric according to claim 1, characterized in that: The silica nanoparticles are pretreated before being added to the bio-based hot melt adhesive. The specific steps are as follows: Premixing: premix the hydrophobic silica nanoparticles with the bio-based hot melt adhesive and stir at a low speed; Ultrasonic dispersion: The mixture is dispersed by ultrasound; Degassing by standing: After dispersion, let it stand to eliminate bubbles in the colloid.

5. The bio-based wear-resistant fabric according to claim 1, characterized in that: The concentration of silicon dioxide nanoparticles added to the polytetrafluoroethylene electrospun nanofilm layer is 1-3wt%.

6. The bio-based wear-resistant fabric according to claim 1, characterized in that: The core layer of the core-shell structure is hydrophobic silica nanoparticles, and the shell layer is graphene oxide.

7. The bio-based wear-resistant fabric according to claim 6, characterized in that: The mass ratio of silica nanoparticles to graphene oxide in the core-shell structure is 5:

1.

8. The bio-based wear-resistant fabric according to claim 1, characterized in that: The preparation of the core-shell structure, the specific steps are: Hydrophobic modification of silica nanoparticles: disperse silica nanoparticles in ethanol, add silane coupling agent, stir, centrifuge and wash, and then dry; Graphene oxide coating: hydrophobically modified silica nanoparticles and graphene oxide were added to deionized water and ultrasonically dispersed; A cross-linking agent is added, the mixture is centrifuged and freeze-dried to obtain a core-shell structure.

9. The bio-based wear-resistant fabric according to claim 1, characterized in that: The silica nanoparticles in the bio-based hot melt adhesive have different particle sizes from the silica nanoparticles added to the polytetrafluoroethylene electrospun nanofilm layer. The silica nanoparticles in the bio-based hot melt adhesive have a particle size of 10-30 nm, while the silica nanoparticles in the polytetrafluoroethylene electrospun nanofilm layer have a particle size of 50-80 nm.

10. A method for preparing the bio-based wear-resistant fabric according to any one of claims 1 to 9, characterized in that: The specific steps are: S1. Preparation of bio-based nylon fabric layer: one or more of bio-based nylon 56, bio-based nylon 66 or bio-based nylon 1010 are subjected to fabric joining, desizing, dyeing, drying, intermediate inspection, shaping and final inspection to obtain a bio-based nylon fabric layer; S2. Preparation of polytetrafluoroethylene electrospun nanofilm layer: a polytetrafluoroethylene aqueous emulsion, a polyvidone aqueous solution and an antistatic additive are blended to obtain an electrospinning solution, and the electrospinning solution is prepared by an electrospinning process. The prepared polytetrafluoroethylene electrospun nanofilm layer is stretched in a single direction for the first time, and allowed to stand for finalization; and then stretched for a second time in the direction of the first stretching; S3, gluing and laminating: placing the stretched polytetrafluoroethylene electrospun nano-membrane layer on a laminating machine, heating and melting the pretreated bio-based hot melt adhesive and evenly coating it on the surface of the membrane layer, and laminating the bio-based nylon fabric layer and the nylon warp knitted base yarn with the polytetrafluoroethylene electrospun nano-membrane layer coated with the hot melt adhesive; S4. Curing: Place the laminated bio-based wear-resistant fabric in a curing room for curing, and the fabric will be ready after curing.

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