Antibacterial nylon fabric and preparation method thereof

Abstract

The invention relates to the technical field of textile fabrics, in particular to an antibacterial nylon fabric and a preparation method thereof. The antibacterial nylon fabric is prepared from the following materials in parts by weight: 65 to 75 parts of nylon 66, 8 to 10 parts of modified nano zinc oxide, 2 to 3 parts of silver-loaded zirconium phosphate, 3 to 5 parts of compatilizer, 0.2 to 0.5 part of antioxidant and 0.5 to 1 part of lubricant. Wherein the modified nano-zinc oxide is obtained by firstly coating nano-zinc oxide with polydopamine and then grafting the coated nano-zinc oxide with a silane coupling agent. According to the antibacterial nylon fabric and the preparation method thereof, the durability of the antibacterial performance of the antibacterial nylon fabric is improved, and the effective antibacterial capacity is still kept after the antibacterial nylon fabric is washed for multiple times.

Description

Technical Field

[0001] This invention relates to the field of textile fabric technology, specifically to an antibacterial nylon fabric and its preparation method. Background Technology

[0002] Nylon fabric, chemically known as polyamide fiber, is a widely used synthetic fiber. Nylon fabric possesses many excellent properties, such as high abrasion resistance, strong toughness and durability, resistance to fading, deformation and aging, good waterproof and breathable properties, and the ability to keep the body dry and comfortable. Therefore, nylon fabric is widely used in various fields such as sports and outdoor products, bags, and home textiles.

[0003] With increasing demands for health and quality of life, antibacterial properties have become an important indicator for textile fabrics. Antibacterial nylon fabrics have emerged to address this need, as they can inhibit bacterial growth and reproduction to a certain extent, thus protecting consumers' health. Antibacterial nylon fabrics primarily achieve their antibacterial function by adding antibacterial agents to nylon fibers or applying antibacterial finishing agents during the fabric finishing process.

[0004] Currently, a wide variety of antibacterial agents are used in antibacterial nylon fabrics on the market, including inorganic antibacterial agents (such as nano silver, nano copper oxide, titanium dioxide, and zinc oxide), organic antibacterial agents (such as quaternary ammonium salts, guanidines, halogenated amines, and halogenated phenols), and natural antibacterial agents (such as ε-polylysine). These antibacterial agents exert their antibacterial effects through different mechanisms of action, such as disrupting bacterial cell membranes and interfering with bacterial metabolism.

[0005] The antibacterial properties of some antibacterial nylon fabrics decrease significantly after repeated washing. This is mainly because the antibacterial agent is not firmly bonded to the nylon fibers and easily detaches during washing. Therefore, this invention provides an antibacterial nylon fabric and its preparation method. Summary of the Invention

[0006] The purpose of this invention is to provide an antibacterial nylon fabric and its preparation method, which improves the durability of the antibacterial properties of the antibacterial nylon fabric and enables it to maintain effective antibacterial ability after multiple washes.

[0007] In a first aspect, the present invention provides an antibacterial nylon fabric comprising the following materials in parts by weight: 65-75 parts of nylon 66, 8-10 parts of modified nano zinc oxide, 2-3 parts of silver-loaded zirconium phosphate, 3-5 parts of compatibilizer, 0.2-0.5 parts of antioxidant, and 0.5-1 parts of lubricant; wherein the modified nano zinc oxide is obtained by first coating nano zinc oxide with polydopamine and then grafting it using a silane coupling agent.

[0008] Further, the polydopamine coating step includes: adding nano zinc oxide to Tris-HCl buffer, ultrasonically dispersing, adding dopamine hydrochloride, stirring at 200-300 rpm, reacting at room temperature for 10-12 h, maintaining pH=8.5±0.1, and after the reaction is completed, centrifuging to collect, washing, and drying to obtain PDA-coated nano zinc oxide.

[0009] Furthermore, the ratio of the amount of nano zinc oxide, dopamine hydrochloride and Tris-HCl buffer is (10-12) g: (3-4) g: (100-120) mL.

[0010] Further, the silane coupling agent grafting step includes: immersing 1g of polydopamine-coated nano zinc oxide in 20-25mL of an ethanol solution of silane coupling agent, reacting in a constant temperature water bath at 100-200rpm and 55-65℃ for 4-6h, and centrifuging, washing and drying after the reaction is completed to obtain the final product.

[0011] Furthermore, the concentration of the ethanol solution of the silane coupling agent is 5-7 g / 100 mL.

[0012] Further, the preparation method of the silver-loaded zirconium phosphate includes: pretreating zirconium phosphate by impregnation with hydrochloric acid to obtain activated zirconium phosphate, dispersing it in a 0.1-0.2 mol / L AgNO3 solution, adjusting the pH to 4-5, reacting in a constant temperature water bath at 300-400 rpm and 55-65℃ for 6-8 hours, and then centrifuging, washing, drying, and sieving to obtain the final product.

[0013] Further, the hydrochloric acid impregnation pretreatment step includes: adding 1g of zirconium phosphate powder to 9-11mL of 1-1.2mol / L hydrochloric acid aqueous solution, stirring for 2-3h, centrifuging at 5000rpm for 10-15min, washing with deionized water until neutral, and drying at 70-80℃ for 10-12h.

[0014] Furthermore, the ratio of the activated zirconium phosphate to the AgNO3 solution is 1 g: (10-12) mL.

[0015] Secondly, the present invention provides a method for preparing antibacterial nylon fabric, comprising the following steps: adding nylon 66, modified nano zinc oxide, silver-loaded zirconium phosphate, compatibilizer, antioxidant, and lubricant to a twin-screw extruder in proportion, and extruding and granulating; melting and spinning the masterbatch, and then heat-setting it by steam treatment at 125-135℃ for 30-40 minutes to obtain antibacterial nylon fiber; cutting the fiber to 38-51mm, and making yarn through opening → carding → drawing → roving → spinning → winding processes, weaving it on a loom with a warp density of 80-120 threads / inch and a weft density of 60-100 threads / inch, and obtaining the antibacterial nylon fabric after hot air setting at 180-190℃ for 30-40 seconds.

[0016] Furthermore, the twin-screw extruder has a melt temperature of 230-250℃ and a screw speed of 200-300 rpm; the spinning temperature is 240-260℃ and the draw ratio is 3:1.

[0017] The beneficial effects of this invention are as follows: This invention employs a synergistic modification strategy of polydopamine (PDA) coating and silane coupling agent grafting to construct a multi-level interface enhancement system of "PDA anchoring + silane bridging". The PDA coating layer forms a dense adsorption layer on the surface of nano-zinc oxide through π-π stacking and hydrogen bonding, significantly enhancing the initial bonding force between the filler and the nylon substrate. The silane coupling agent further grafts organic functional groups onto the surface of the PDA layer through hydrolysis and condensation reactions, forming a flexible interface layer compatible with the nylon molecular chains, effectively alleviating stress concentration.

[0018] In this invention, the anchoring mechanism of PDA coating involves the self-polymerization of dopamine under weakly alkaline conditions to form a PDA nanolayer. The catechol groups of dopamine can form a hydrogen bond network with the amide groups of nylon 66, while the π-conjugated structure of PDA enhances interfacial adhesion through π-π interactions. Experiments show that PDA coating reduces the shedding rate of nano-zinc oxide from the nylon matrix, effectively inhibiting physical loss during washing.

[0019] In this invention, the bridging effect of the silane coupling agent is achieved by the hydrolysis of the ethoxy group of the silane coupling agent KH550 to generate silanol, which then undergoes a condensation reaction with the hydroxyl groups on the PDA surface to form a Si-OC covalent bond. Meanwhile, the vinyl group at the other end undergoes free radical graft polymerization with the nylon molecular chain. This "molecular bridge" structure enhances the shear strength of the filler-substrate interface, significantly improving stress transfer efficiency.

[0020] In this invention, ZnO / ZrP-Ag was constructed. + A dual-phase antibacterial system achieves a spatiotemporal synergistic effect through the contact sterilization of nano-zinc oxide and the sustained-release sterilization of silver-loaded zirconium phosphate. Modified nano-zinc oxide surface Zn 2+ Electrostatic adsorption can disrupt bacterial cell membranes, while silver-loaded zirconium phosphate achieves Ag2 adsorption through interlayer ion exchange. + The controlled release of Zn forms a dual antibacterial defense line of "instant kill - sustained inhibition". When bacteria come into contact with the material surface, Zn... 2+ Zirconium phosphate penetrates the cell membrane via a "Trojan horse" effect, triggering an intracellular ROS burst and protein denaturation. Its layered structure, after hydrochloric acid pretreatment to induce lattice defects, still retains high Ag content even after washing. + Retention amount ensures long-lasting antibacterial properties.

[0021] This invention abandons the traditional organic antibacterial agent addition and adhesive coating process, achieving the intrinsic antibacterial function of fibers through in-situ modification. Modified nano-zinc oxide and silver-loaded zirconium phosphate are directly dispersed in nylon melt, forming a fiber structure with gradient antibacterial activity through melt spinning, avoiding the thermal decomposition of organic antibacterial agents and the aging problems of adhesives. The modified fillers are oriented along the fiber axis under shear force, forming a "core-shell" structure: a PDA / silane composite layer acts as the shell to enhance interfacial compatibility, and ZnO / ZrP-Ag... + The core layer provides antibacterial properties.

[0022] This invention constructs a three-dimensional network-reinforced structure through multi-level modification of fillers and cross-linking design of the matrix. Under humid and hot conditions, the catechol groups of PDA can undergo Michael addition reactions with the terminal amino groups of nylon to form a dynamic cross-linked network; the vinyl groups of the silane coupling agent participate in the nylon crystallization process, promote the β-crystal transformation, and improve the material's resistance to humid and hot aging. Detailed Implementation

[0023] The technical solution of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] It should be noted that the maleic anhydride-grafted polyethylene used in this invention was purchased from DuPont, USA, and is maleic anhydride-grafted low-density polyethylene, grade 4208, with a density of ρ = 0.938 g / cm³. 3 The grafting rate is 0.5%-1%. Example

[0025] This embodiment provides an antibacterial nylon fabric, comprising the following materials in parts by weight: 70 parts nylon 66, 9 parts modified nano zinc oxide, 2.5 parts silver-loaded zirconium phosphate, 4 parts compatibilizer, 0.3 parts antioxidant, and 0.7 parts lubricant; The modified nano-zinc oxide is obtained by first coating nano-zinc oxide with polydopamine and then grafting it with a silane coupling agent. Specifically, 11g of nano-zinc oxide is added to 110mL of Tris-HCl buffer, ultrasonically dispersed at 300W and 40kHz for 30min, 3.5g of dopamine hydrochloride is added, the stirring speed is controlled at 250rpm, and the reaction is carried out at room temperature (25℃) for 11h. The pH is maintained at 8.5 by adding 0.1M HCl / NaOH dropwise. After the reaction is completed, the nano-zinc oxide is collected by centrifugation at 8000rpm for 10min, washed three times with deionized water, and vacuum dried at 60℃ for 12h to obtain PDA-coated nano-zinc oxide. 6g of... KH-550 silane coupling agent was mixed with 100 mL of anhydrous ethanol and magnetically stirred for 30 minutes to obtain an ethanol solution of silane coupling agent; 1 g of nano zinc oxide coated with polydopamine was immersed in 22 mL of ethanol solution of silane coupling agent and reacted in a constant temperature water bath at 150 rpm and 60 °C for 5 h. After the reaction was completed, the mixture was centrifuged at 5000 rpm for 5 min, washed twice with ethanol, and vacuum dried at 60 °C for 6 h to obtain the final product. The preparation method of silver-loaded zirconium phosphate includes: adding 1g of zirconium phosphate powder to 10mL of 1.1mol / L hydrochloric acid aqueous solution, stirring for 2.5h, centrifuging at 5000rpm for 12.5min, washing with deionized water until neutral, drying at 75℃ for 11h to obtain activated zirconium phosphate, dispersing it in 0.15mol / L AgNO3 solution, with a volume ratio of activated zirconium phosphate to AgNO3 solution of 1g:11mL; adjusting the pH to 4.5 with ammonia water, reacting in a constant temperature water bath at 350rpm and 60℃ for 7h, centrifuging at 8000rpm for 10min, and washing three times with deionized water until the filtrate is free of Ag. + The residue (detectable with NaCl solution, no white AgCl precipitate formed) is obtained by vacuum drying at 60℃ for 12 hours and passing through a 200-mesh sieve. Among them, the compatibilizer is maleic anhydride-grafted polyethylene; the antioxidant is antioxidant 1010; and the lubricant is calcium stearate. The preparation method of this antibacterial nylon fabric includes the following steps: Nylon 66, modified nano zinc oxide, silver-loaded zirconium phosphate, compatibilizer, antioxidant, and lubricant are added to a twin-screw extruder in proportion, with a melt temperature of 240℃ and a screw speed of 250 rpm, and extruded and granulated; the masterbatch is melt-spun, with the spinning temperature controlled at 250℃ and the draw ratio at 3:1, and then heat-set by steam treatment at 130℃ for 35 minutes to obtain antibacterial nylon fibers; the fibers are cut to 44mm, and processed through opening → carding → drawing → roving → spinning → winding to make yarn, which is then woven on a loom with a warp density of 100 ends / inch and a weft density of 80 ends / inch, and then hot-set at 185℃ for 35 seconds to obtain the antibacterial nylon fabric. Example

[0026] This embodiment provides an antibacterial nylon fabric, comprising the following materials in parts by weight: 65 parts nylon 66, 8 parts modified nano zinc oxide, 2 parts silver-loaded zirconium phosphate, 3 parts compatibilizer, 0.2 parts antioxidant, and 0.5 parts lubricant; The modified nano-zinc oxide is obtained by first coating nano-zinc oxide with polydopamine and then grafting it with a silane coupling agent. Specifically, 10g of nano-zinc oxide is added to 100mL of Tris-HCl buffer, ultrasonically dispersed at 300W and 40kHz for 30min, 3g of dopamine hydrochloride is added, the stirring speed is controlled at 200rpm, and the reaction is carried out at room temperature (25℃) for 10h. The pH is maintained at 8.5 by adding 0.1M HCl / NaOH dropwise. After the reaction is completed, the nano-zinc oxide is collected by centrifugation at 8000rpm for 10min, washed three times with deionized water, and vacuum dried at 60℃ for 12h to obtain PDA-coated nano-zinc oxide. 5g of... KH-550 silane coupling agent was mixed with 100 mL of anhydrous ethanol and magnetically stirred for 30 minutes to obtain an ethanol solution of silane coupling agent; 1 g of nano zinc oxide coated with polydopamine was immersed in 20 mL of ethanol solution of silane coupling agent and reacted in a constant temperature water bath at 100 rpm and 55 °C for 4 h. After the reaction was completed, the mixture was centrifuged at 5000 rpm for 5 min, washed twice with ethanol, and vacuum dried at 60 °C for 6 h to obtain the final product. The preparation method of silver-loaded zirconium phosphate includes: adding 1g of zirconium phosphate powder to 9mL of 1mol / L hydrochloric acid aqueous solution, stirring for 2h, centrifuging at 5000rpm for 10min, washing with deionized water until neutral, drying at 70℃ for 10h to obtain activated zirconium phosphate, dispersing it in 0.1mol / L AgNO3 solution, with a volume ratio of activated zirconium phosphate to AgNO3 solution of 1g:10mL; adjusting the pH to 4 with ammonia water, reacting in a constant temperature water bath at 300rpm and 55℃ for 6h, centrifuging at 8000rpm for 10min, and washing three times with deionized water until the filtrate is free of Ag. + The residue (detectable with NaCl solution, no white AgCl precipitate formed) is obtained by vacuum drying at 60℃ for 12 hours and passing through a 200-mesh sieve. Among them, the compatibilizer is maleic anhydride-grafted polyethylene; the antioxidant is antioxidant 1010; and the lubricant is calcium stearate. The preparation method of this antibacterial nylon fabric includes the following steps: Nylon 66, modified nano zinc oxide, silver-loaded zirconium phosphate, compatibilizer, antioxidant, and lubricant are added to a twin-screw extruder in proportion, with a melt temperature of 230°C and a screw speed of 200 rpm, and extruded and granulated; the masterbatch is melt-spun, with the spinning temperature controlled at 240°C and the draw ratio at 3:1, and then heat-set by steam treatment at 125°C for 30 minutes to obtain antibacterial nylon fibers; the fibers are cut to 38 mm, and processed through opening → carding → drawing → roving → spinning → winding to form yarn, which is then woven on a loom with a warp density of 80 threads / inch and a weft density of 60 threads / inch, and then hot-set at 180°C for 30 seconds to obtain the antibacterial nylon fabric. Example

[0027] This embodiment provides an antibacterial nylon fabric, comprising the following materials in parts by weight: 75 parts nylon 66, 10 parts modified nano zinc oxide, 3 parts silver-loaded zirconium phosphate, 5 parts compatibilizer, 0.5 parts antioxidant, and 1 part lubricant; The modified nano-zinc oxide is obtained by first coating nano-zinc oxide with polydopamine and then grafting it with a silane coupling agent. Specifically, 12g of nano-zinc oxide is added to 120mL of Tris-HCl buffer, ultrasonically dispersed at 300W and 40kHz for 30min, 4g of dopamine hydrochloride is added, the stirring speed is controlled at 300rpm, and the reaction is carried out at room temperature (25℃) for 12h. The pH is maintained at 8.5 by adding 0.1M HCl / NaOH dropwise. After the reaction is completed, the nano-zinc oxide is collected by centrifugation at 8000rpm for 10min, washed three times with deionized water, and vacuum dried at 60℃ for 12h to obtain PDA-coated nano-zinc oxide. 7g of KH-550 silane coupling agent was mixed with 100 mL of anhydrous ethanol and magnetically stirred for 30 minutes to obtain an ethanol solution of silane coupling agent; 1 g of nano zinc oxide coated with polydopamine was immersed in 25 mL of ethanol solution of silane coupling agent and reacted in a constant temperature water bath at 200 rpm and 65 °C for 6 h. After the reaction was completed, the mixture was centrifuged at 5000 rpm for 5 min, washed twice with ethanol, and vacuum dried at 60 °C for 6 h to obtain the final product. The preparation method of silver-loaded zirconium phosphate includes: adding 1g of zirconium phosphate powder to 11mL of 1.2mol / L hydrochloric acid aqueous solution, stirring for 3h, centrifuging at 5000rpm for 15min, washing with deionized water until neutral, drying at 80℃ for 12h to obtain activated zirconium phosphate, dispersing it in 0.2mol / L AgNO3 solution, with a volume ratio of activated zirconium phosphate to AgNO3 solution of 1g:12mL; adjusting the pH to 5 with ammonia water, reacting in a constant temperature water bath at 400rpm and 65℃ for 8h, centrifuging at 8000rpm for 10min, and washing three times with deionized water until the filtrate is free of Ag. +The residue (detectable with NaCl solution, no white AgCl precipitate formed) is obtained by vacuum drying at 60℃ for 12 hours and passing through a 200-mesh sieve. Among them, the compatibilizer is maleic anhydride-grafted polyethylene; the antioxidant is antioxidant 1010; and the lubricant is calcium stearate. The preparation method of this antibacterial nylon fabric includes the following steps: Nylon 66, modified nano zinc oxide, silver-loaded zirconium phosphate, compatibilizer, antioxidant, and lubricant are added to a twin-screw extruder in proportion, with a melt temperature of 250°C and a screw speed of 300 rpm, and extruded and granulated; the masterbatch is melt-spun, with the spinning temperature controlled at 260°C and the draw ratio at 3:1, and then heat-set by steam treatment at 135°C for 40 minutes to obtain antibacterial nylon fibers; the fibers are cut to 51 mm, and processed through opening → carding → drawing → roving → spinning → winding to make yarn, which is then woven on a loom with a warp density of 120 ends / inch and a weft density of 100 ends / inch, and then hot-set at 190°C for 40 seconds to obtain the antibacterial nylon fabric. Example

[0028] This embodiment provides an antibacterial nylon fabric, comprising the following materials in parts by weight: 65 parts nylon 66, 10 parts modified nano zinc oxide, 2 parts silver-loaded zirconium phosphate, 5 parts compatibilizer, 0.2 parts antioxidant, and 1 part lubricant; The modified nano-zinc oxide is obtained by first coating nano-zinc oxide with polydopamine and then grafting it with a silane coupling agent. Specifically, 10g of nano-zinc oxide is added to 120mL of Tris-HCl buffer, ultrasonically dispersed at 300W and 40kHz for 30min, 3g of dopamine hydrochloride is added, the stirring speed is controlled at 300rpm, and the reaction is carried out at room temperature (25℃) for 10h. The pH is maintained at 8.5 by adding 0.1M HCl / NaOH dropwise. After the reaction is completed, the nano-zinc oxide is collected by centrifugation at 8000rpm for 10min, washed three times with deionized water, and vacuum dried at 60℃ for 12h to obtain PDA-coated nano-zinc oxide. 5g of... KH-550 silane coupling agent was mixed with 100 mL of anhydrous ethanol and magnetically stirred for 30 minutes to obtain an ethanol solution of silane coupling agent; 1 g of nano zinc oxide coated with polydopamine was immersed in 25 mL of ethanol solution of silane coupling agent and reacted in a constant temperature water bath at 100 rpm and 65 °C for 4 h. After the reaction was completed, the mixture was centrifuged at 5000 rpm for 5 min, washed twice with ethanol, and vacuum dried at 60 °C for 6 h to obtain the final product. The preparation method of silver-loaded zirconium phosphate includes: adding 1g of zirconium phosphate powder to 11mL of 1mol / L hydrochloric acid aqueous solution, stirring for 3h, centrifuging at 5000rpm for 10min, washing with deionized water until neutral, drying at 80℃ for 10h to obtain activated zirconium phosphate, dispersing it in 0.2mol / L AgNO3 solution, with a volume ratio of activated zirconium phosphate to AgNO3 solution of 1g:10mL; adjusting the pH to 4 with ammonia water, reacting in a constant temperature water bath at 55℃ and 400rpm for 8h, centrifuging at 8000rpm for 10min, and washing three times with deionized water until the filtrate is free of Ag. + The residue (detectable with NaCl solution, no white AgCl precipitate formed) is obtained by vacuum drying at 60℃ for 12 hours and passing through a 200-mesh sieve. Among them, the compatibilizer is maleic anhydride-grafted polyethylene; the antioxidant is antioxidant 1010; and the lubricant is calcium stearate. The preparation method of this antibacterial nylon fabric includes the following steps: Nylon 66, modified nano zinc oxide, silver-loaded zirconium phosphate, compatibilizer, antioxidant, and lubricant are added to a twin-screw extruder in proportion, with a melt temperature of 230℃ and a screw speed of 300 rpm, and extruded and granulated; the masterbatch is melt-spun, with the spinning temperature controlled at 240℃ and the draw ratio at 3:1, and then heat-set by steam treatment at 135℃ for 30 minutes to obtain antibacterial nylon fibers; the fibers are cut to 51mm, and processed through opening → carding → drawing → roving → spinning → winding to make yarn, which is then woven on a loom with a warp density of 80 threads / inch and a weft density of 100 threads / inch, and then hot-set at 1800℃ for 40 seconds to obtain the antibacterial nylon fabric.

[0029] Comparative Example 1 In Comparative Example 1, the nano zinc oxide was not coated with polydopamine, but otherwise it was the same as in Example 1, and the preparation steps were the same as in Example 1.

[0030] Comparative Example 2 In Comparative Example 2, the nano zinc oxide was not grafted with a silane coupling agent, and the rest was the same as in Example 1, with the same preparation steps.

[0031] Comparative Example 3 In Comparative Example 3, the modified nano zinc oxide was replaced with an equal mass of nano zinc oxide, and the rest was the same as in Example 1, with the same preparation steps.

[0032] Comparative Example 4 The raw materials in Comparative Example 4 did not contain modified nano zinc oxide, but were otherwise the same as in Example 1, and the preparation steps were the same as in Example 1.

[0033] Comparative Example 5 In Comparative Example 5, the silver-loaded zirconium phosphate was replaced with an equal mass of zirconium phosphate, and the rest was the same as in Example 1, with the same preparation steps.

[0034] Comparative Example 6 The raw materials in Comparative Example 6 do not contain silver-loaded zirconium phosphate, and the rest are the same as in Example 1. The preparation steps are the same as in Example 1.

[0035] Test Example 1: The antibacterial nylon fabrics prepared in Examples 1-4 and Comparative Examples 1-6 were tested as follows: Antimicrobial test: Referencing GB / T 20944.3-2008 "Evaluation of Antimicrobial Properties of Textiles - Shaking Method", the test strains were *Escherichia coli* (ATCC 8739) and *Staphylococcus aureus* (ATCC 6538). First, the fabric was cut into 5cm × 5cm samples, sterilized with ultraviolet light for 30 minutes, and then the bacterial solution (concentration 1×10⁻⁶) was... 5 The sample (CFU / mL) was contacted with the test sample in 0.03 mol / L PBS buffer at 150 rpm and 37°C for 18 h. The shaken solution was serially diluted and spread onto agar plates, incubated at 37°C for 24 h, and the colony count was determined. The antibacterial rate (%) = (colony count in the blank control group - colony count in the test sample group) / colony count in the blank control group × 100%. The initial antibacterial rate was obtained by directly testing the unwashed sample. The antibacterial rate after washing was tested by washing 50 times (40°C, 0.5% standard detergent) according to GB / T 8629-2017 standard. Mechanical properties: Referring to GB / T 3923.1-2013 "Textiles - Tensile Properties of Fabrics - Strip Method", a 25cm × 5cm specimen was tested using a universal testing machine (Instron 5565). The clamping distance was 20cm, and the tensile speed was 100mm / min. Tensile strength (MPa) = maximum tensile force (N) / specimen cross-sectional area (mm²) 2 ); Moist heat aging resistance test: Tensile strength was tested after being placed at 70℃ and 95% relative humidity for 168 hours, and the tensile strength retention rate was calculated.

[0036] The results are shown in Table 1 below: Table 1 Initial antibacterial rate (%) Antibacterial rate after washing (%) Tensile strength (MPa) Tensile strength retention rate (%) Example 1 99.9 98.5 48.2 92.1 Example 2 99.6 97.8 46.5 90.3 Example 3 99.8 98.2 49.1 91.5 Example 4 99.4 97.1 45.8 89.7 Comparative Example 1 95.2 78.3 41.5 82.4 Comparative Example 2 97.1 85.6 43.2 85.0 Comparative Example 3 88.7 65.4 39.8 78.9 Comparative Example 4 72.3 48.9 37.6 74.2 Comparative Example 5 84.5 62.1 42.0 80.5 Based on the above data, the initial antibacterial rate of Examples 1-4 was >99%, and the retention rate after 50 washes was >97%, indicating that the synergistic effect of modified nano-zinc oxide (PDA coating + silane grafting) and silver-loaded zirconium phosphate significantly improved the antibacterial durability. PDA coating reinforces the filler-substrate bond, reducing wash loss; the slow-release Ag from silver-loaded zirconium phosphate... +Provides long-lasting antibacterial effect. Comparative Example 1 showed an antibacterial rate of only 78.3% after washing, indicating that the uncoated nano-zinc oxide was easily detached, leading to a significant decrease in antibacterial performance. Comparative Example 2 showed an antibacterial rate higher than Comparative Example 1 but lower than the Example, indicating that the silane coupling agent further improved the filler dispersibility and interfacial bonding. Comparative Examples 3-4 showed the lowest antibacterial rates, proving that the modified nano-zinc oxide was the key antibacterial component. Comparative Examples 5-6 showed significantly lower antibacterial rates than the Example, indicating that the Ag in silver-loaded zirconium phosphate... + Sustained release is indispensable for broad-spectrum antibacterial activity.

[0037] Furthermore, the tensile strength of Examples 1-4 was significantly higher than that of the comparative examples, attributed to the improved interfacial bonding force resulting from the multi-stage modification of the filler (PDA anchoring + nylon grafting). The tensile strength retention rate after damp heat aging was >89%, indicating excellent damp heat resistance. The decreased tensile strength of Comparative Examples 1-2 suggests that incompletely modified fillers caused interfacial defects, weakening mechanical properties. The low tensile strength of Comparative Examples 3-6 was due to filler agglomeration or absence leading to matrix discontinuity.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention; those skilled in the art should understand that modifications or equivalent substitutions can still be made to the present invention; and all technical solutions and improvements that do not depart from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims

1. An antibacterial nylon fabric, characterized in that, The material comprises the following parts by weight: 65-75 parts of nylon 66, 8-10 parts of modified nano zinc oxide, 2-3 parts of silver-loaded zirconium phosphate, 3-5 parts of compatibilizer, 0.2-0.5 parts of antioxidant, and 0.5-1 parts of lubricant; wherein the modified nano zinc oxide is obtained by first coating nano zinc oxide with polydopamine and then grafting it with a silane coupling agent.

2. The antibacterial nylon fabric according to claim 1, characterized in that, The polydopamine coating step includes: adding nano zinc oxide to Tris-HCl buffer, ultrasonically dispersing, adding dopamine hydrochloride, stirring at 200-300 rpm, reacting at room temperature for 10-12 h, maintaining pH=8.5±0.1, and after the reaction is completed, collecting by centrifugation, washing, and drying to obtain PDA-coated nano zinc oxide.

3. The antibacterial nylon fabric according to claim 2, characterized in that, The ratio of the amount of nano zinc oxide, dopamine hydrochloride and Tris-HCl buffer is (10-12) g: (3-4) g: (100-120) mL.

4. The antibacterial nylon fabric according to claim 2, characterized in that, The silane coupling agent grafting step includes: immersing 1g of polydopamine-coated nano zinc oxide in 20-25mL of ethanol solution of silane coupling agent, reacting in a constant temperature water bath at 100-200rpm and 55-65℃ for 4-6h, and centrifuging, washing and drying after the reaction is completed to obtain the final product.

5. The antibacterial nylon fabric according to claim 2, characterized in that, The concentration of the ethanol solution of the silane coupling agent is 5-7 g / 100 mL.

6. The antibacterial nylon fabric according to claim 1, characterized in that, The preparation method of the silver-loaded zirconium phosphate includes: pretreating zirconium phosphate by impregnation with hydrochloric acid to obtain activated zirconium phosphate, dispersing it in a 0.1-0.2 mol / L AgNO3 solution, adjusting the pH to 4-5, reacting in a constant temperature water bath at 300-400 rpm and 55-65℃ for 6-8 hours, and then centrifuging, washing, drying, and sieving to obtain the final product.

7. The antibacterial nylon fabric according to claim 6, characterized in that, The hydrochloric acid impregnation pretreatment step includes: adding 1g of zirconium phosphate powder to 9-11mL of 1-1.2mol / L hydrochloric acid aqueous solution, stirring for 2-3h, centrifuging at 5000rpm for 10-15min, washing with deionized water until neutral, and drying at 70-80℃ for 10-12h.

8. The antibacterial nylon fabric according to claim 6, characterized in that, The ratio of activated zirconium phosphate to AgNO3 solution is 1 g : (10-12) mL.

9. A method for preparing an antibacterial nylon fabric as described in any one of claims 1-8, characterized in that, step... include: Nylon 66, modified nano zinc oxide, silver-loaded zirconium phosphate, compatibilizer, antioxidant, and lubricant are added to a twin-screw extruder in proportion and extruded and granulated. The masterbatch is melt-spun and then heat-set by steam treatment at 125-135℃ for 30-40 minutes to obtain antibacterial nylon fiber. The fiber is cut to 38-51mm and processed through opening, carding, drawing, roving, spinning, and winding to make yarn. The yarn is woven on a loom with a warp density of 80-120 threads / inch and a weft density of 60-100 threads / inch. After hot air setting at 180-190℃ for 30-40 seconds, the antibacterial nylon fabric is obtained.

10. The method for preparing antibacterial nylon fabric according to claim 9, characterized in that, The twin-screw extruder has a melt temperature of 230-250℃ and a screw speed of 200-300 rpm; the spinning temperature is 240-260℃ and the draw ratio is 3:1.