UHMWPE fiber containing GO / MOFs antibacterial composite material and application of UHMWPE fiber

Abstract

The invention belongs to the technical field of fiber processing, and particularly discloses a UHMWPE fiber containing a GO / MOFs antibacterial composite material and application of the UHMWPE fiber. A preparation method of the UHMWPE fiber containing the GO / MOFs antibacterial composite material comprises the following steps: (1) preparation of the GO / MOFs antibacterial composite material: dispersing GO and antibacterial MOFs into a solvent, performing ultrasonic treatment for 2-3 hours, filtering and drying to obtain the GO / MOFs antibacterial composite material; and (2) dispersing the GO / MOFs antibacterial composite material in white oil, adding a dispersing agent, mechanically stirring at normal temperature for 30-35 minutes, adding PE powder, mixing, heating and stirring to form a UHMWPE swelling solution, performing twin-screw extrusion, spinning and cooling molding to obtain gel fibers, and performing pre-stretching, extraction, drying and multi-stage hot stretching to obtain the UHMWPE fibers. The fiber prepared by the invention has creep-resistant and antibacterial effects.

Description

Technical Field

[0001] This application relates to the technical field of fiber processing, and in particular to a UHMWPE fiber containing GO / MOFs antibacterial composite material and its applications. Background Technology

[0002] UHMWPE fiber, or ultra-high molecular weight polyethylene fiber, is a high-performance fiber made from polyethylene resin with a molecular weight of over 1 million. It has high strength, light weight, and corrosion resistance, and is mainly used in protective, outdoor, and industrial fields. However, its insufficient creep resistance limits its application.

[0003] In existing technologies, inorganic nanomaterials, such as nano-silica (SiO2) and carbon nanotubes (CNTs), are often combined with UHMWPE fibers to improve their creep resistance. However, this approach suffers from problems such as easy agglomeration and insufficient design flexibility, which in turn leads to a deterioration in their creep resistance. Summary of the Invention

[0004] To improve the poor creep resistance of UHMWPE fibers, this application provides a UHMWPE fiber containing GO / MOF antibacterial composite material and its application.

[0005] This application provides a UHMWPE fiber containing GO / MOFs antibacterial composite material and its application, using the following technical solution: A UHMWPE fiber fabric containing GO / MOFs antibacterial composite material includes the following steps: (1) Preparation of GO / MOFs antibacterial composite material: GO and antibacterial MOFs were dispersed in a solvent, sonicated for 2-3 hours, filtered and dried to obtain GO / MOFs antibacterial composite material; The solvent is one of water, ethanol, or dimethyl sulfoxide.

[0006] (2) Disperse the GO / MOFs antibacterial composite material in white oil, add 0.1-0.5wt% dispersant, mechanically stir at room temperature for 30-35 min at a stirring rate of 150-200 r / min, add PE powder, mix and heat, stirring at a stirring speed of 50-60 r / min, stirring temperature of 100-120℃, stirring time of 60-100 min to form a UHMWPE swelling solution, which is then extruded by twin screws, spun, cooled and shaped to obtain gel fiber, and then pre-stretched, extracted, dried and multi-stage hot stretched to obtain UHMWPE fiber.

[0007] By employing the above technical solutions, MOFs possess a porous structure and high specific surface area, enabling them to load and slowly release antibacterial ions, thereby exerting an antibacterial effect. GO (graphene oxide) exhibits excellent physical barrier properties and certain antibacterial activity; its oxygen-containing functional groups can combine with MOF materials to form stable composite materials, while simultaneously enhancing the dispersibility of the material. The addition of dispersants helps to uniformly disperse GO and MOFs in the subsequent matrix, preventing aggregation and ensuring the uniformity of the antibacterial effect.

[0008] GO / MOFs antibacterial composite materials were dispersed in white oil, and mechanical stirring was used to improve dispersion uniformity and stability. PE powder was added to the white oil and heated to allow the PE powder to swell, forming a homogeneous swollen solution. The melt was extruded through a spinneret and rapidly cooled to form gel fibers. The gel fibers underwent preliminary stretching to improve fiber orientation and mechanical properties. Residual solvents (such as white oil) were extracted from the fibers to ensure fiber purity and stability. Multi-stage thermal stretching further improved the fiber strength and modulus, while optimizing the distribution and fixation of the antibacterial material.

[0009] GO exhibits poor thermal stability in air. In oxygen-rich environments above 200°C, its oxygen-containing functional groups decompose significantly, releasing substances such as CO, CO2, and H2O, resulting in a mass loss exceeding 30%, while the carbon skeleton also begins to shrink. However, GO dispersed in white oil, due to the isolation from oxygen, demonstrates significantly improved thermal stability. Under processing conditions not exceeding 300°C, GO experiences only slight weight loss, with the carbon skeleton remaining largely intact and showing no obvious oxidation. The resulting UHMWPE fibers not only retain the excellent properties of UHMWPE, such as high strength and high abrasion resistance, but also possess a long-lasting antibacterial effect due to the addition of the GO / MOFs antibacterial composite material.

[0010] GO / MOF composite antibacterial materials exhibit superior dispersibility and can achieve broader functionalization through the diverse selectivity of metal centers and ligands. Furthermore, their porous structure and polar groups can more effectively form a stable structure with fibers, thereby further improving the mechanical properties, antibacterial properties, and creep resistance of UHMWPE fibers.

[0011] Preferably, the twin-screw extrusion parameters are: rotation speed 200-220 r / min, temperature segmentation set to 150-160℃, 230-240℃, 290-300℃, and 270-280℃; spinning parameters: spinning temperature 230-240℃; and pre-stretching parameters: nozzle stretch ratio 1.5-2.

[0012] By adopting the above technical solution, the rotational speed range is moderate, which can ensure good dispersion of GO / MOF antibacterial composite material in UHMWPE matrix, while avoiding thermal degradation or filler structure damage caused by excessive shear. Low-temperature feeding prevents premature melting of PE powder and ensures stable conveying; gradual heating promotes melting of PE swell and thorough mixing with antibacterial slurry; high temperature ensures complete melting, reduces melt viscosity, and is conducive to uniform dispersion of GO / MOFs.

[0013] Preferred extraction parameters: extraction temperature 25-35℃, fiber feed speed 50-65m / min.

[0014] By adopting the above technical solution, the purpose of extraction is to remove the white oil (dispersion medium) in the gel fiber, form a porous structure, provide space for the orientation of macromolecular chains during subsequent thermal stretching, and at the same time avoid the loss of antibacterial components (GO / MOFs).

[0015] Preferred multi-stage thermal stretching parameters: three-stage and four-stage segmented stretching: temperature 125-145℃, total stretching ratio 5.5-7.

[0016] By adopting the above technical solution, three- or four-stage segmented stretching is selected to gradually release the internal stress of the fiber, improve the orientation degree while avoiding excessive crystallization, reduce the shearing of antibacterial components (GO / MOFs) due to instantaneous shear force, disperse GO / MOFs in the PE matrix, and gradually stretching can make PE chain segments wrap antibacterial particles, thereby improving the interfacial bonding force.

[0017] Secondly, this application also provides the application of UHMWPE fibers containing GO / MOFs antibacterial composite materials in composite yarns.

[0018] Thirdly, this application also provides a composite yarn, which is a core-spun yarn made from the UHMWPE fiber and natural fiber; the natural fiber is soaked in a modifying solution for 5-8 minutes and then dried to obtain the treated fiber; the modifying solution includes a modifier and water, and the modifier includes a mixture of Centella asiatica compound extract, seashell powder-loaded sodium alginate, and hyaluronic acid in a mass ratio of 1:0.59-0.73:0.12-0.34.

[0019] Natural fibers are one of the following: cotton, wool, silk, and linen.

[0020] By adopting the above technical solution, the modified liquid is coated on the surface of natural fibers, which improves the antibacterial properties, mechanical properties and durability of the fibers.

[0021] Centella asiatica extract is typically rich in triterpenoids and flavonoids, possessing broad-spectrum antibacterial, anti-inflammatory, and wound-healing bioactivities, providing antibacterial functionality. Shell powder loaded with sodium alginate offers antibacterial properties, adhesion, and mechanical strength, providing a large specific surface area to adsorb and stabilize the active ingredients, while its microstructure enhances the mechanical properties of the fiber surface. Hyaluronic acid molecules contain numerous hydrophilic groups, which can improve the dryness caused by the hydrophobicity of UHMWPE fibers, and synergistically form a hydrophilic film with sodium alginate, reducing the volatilization of active ingredients.

[0022] Centella asiatica extract is adsorbed onto the surface of sodium alginate loaded with shell powder. Sodium alginate and hyaluronic acid are mixed to form a film that wraps around the fiber, locking the active substances such as Centella asiatica extract and shell powder onto the fiber surface, forming a durable functional coating that subsequently improves the antibacterial properties, mechanical properties and abrasion resistance of the composite yarn.

[0023] Preferably, the preparation method of the Centella asiatica compound extract includes the following steps: (1) Crush the Centella asiatica, disperse it in deionized water, sonicate for 30-35 min, stir at 90-95℃ for 3-4 h, filter, obtain the supernatant, concentrate, freeze dry, and obtain Centella asiatica extract. (2) Disperse the Centella asiatica extract in deionized water, stir for 20-25 min, then add chitosan mixture, dry, grind to obtain Centella asiatica complex extract; The method for preparing the chitosan mixture includes the following steps: dispersing chitosan in an acetic acid solution, adding polyvinylpyrrolidone and silica microspheres, and stirring at a temperature of 55-60℃ for 30-45 minutes to obtain the chitosan mixture.

[0024] By adopting the above technical solutions, pulverization increases the contact area between Centella asiatica and other components, which helps with extraction. Ultrasound makes it easier for the effective components in the cells (such as triterpenoid saponins, flavonoids, etc.) to be released into water. Heating and stirring further promote the extraction of plant active ingredients by water. Freeze-drying preserves the chemical structure of heat-sensitive active ingredients to the maximum extent and obtains a loose, porous powder, which is convenient for subsequent reconstitution and compounding.

[0025] The addition of a chitosan mixture allows the positively charged chitosan to tightly bind with the negatively charged Centella asiatica extract through electrostatic interactions. The chitosan forms a film that encapsulates and cross-links the Centella asiatica extract and silica microspheres, creating a unified three-dimensional network structure. This ultimately enhances the antibacterial properties, flexibility, strength, and toughness of the Centella asiatica composite extract, subsequently allowing it to stably combine with shell powder, hyaluronic acid, and other components to exert a lasting effect.

[0026] In addition, chitosan exhibits excellent film-forming properties, biocompatibility, and natural antibacterial activity in the chitosan mixture, while polyvinylpyrrolidone enhances the stability of the mixture and prevents component aggregation. Silica microspheres provide a rigid framework, enhance mechanical strength, and significantly increase the specific surface area of ​​the material, offering more sites for subsequent loading of Centella asiatica extract.

[0027] Preferably, the method for preparing the shell powder loaded with sodium alginate includes the following steps: Disperse shell powder in sodium hydroxide solution, soak for 1-2 hours, wash with water, calcine at 500-510℃ for 1-2 hours to obtain nano-shell powder, disperse nano-shell powder in deionized water, add carbon nanotubes, stir for 30-35 minutes, filter, dry to obtain composite shell powder. The composite shell powder was dispersed in a sodium alginate solution, stirred for 3-5 minutes, filtered, and dried to obtain shell powder loaded with sodium alginate.

[0028] By employing the above technical solution, sodium hydroxide solution can effectively decompose and dissolve organic impurities in seashells, leaving a pure inorganic framework. It also removes grease and pollutants, exposing more active sites. High-temperature calcination thoroughly removes organic matter, increases porosity and activity, making it more porous and thus a more efficient nanoscale adsorbent carrier.

[0029] Carbon nanotubes can significantly improve the strength and toughness of composite materials. They can wrap around porous nano-shell powder to form a micron-nano hierarchical pore structure, which further increases the specific surface area, adsorption capacity and mechanical properties of the material.

[0030] When composite shell powder is dispersed in a sodium alginate solution, sodium alginate molecules penetrate into the pores of the shell powder and carbon nanotubes, and due to their adhesiveness, adhere tightly to their entire surface. The resulting shell powder loaded with sodium alginate exhibits high antibacterial properties, adhesiveness, and mechanical properties, which subsequently improves the adhesion between the coating and fibers, thereby enhancing the coating's durability.

[0031] Preferably, the mass ratio of the shell powder, carbon nanotubes, and sodium alginate solution is 1:0.32-0.43:35-38.

[0032] By employing the above technical solution and further limiting the mass ratio of shell powder, carbon nanotubes, and sodium alginate solution, the resulting shell powder loaded with sodium alginate exhibits excellent comprehensive performance. After activation, the nano-shell powder possesses a high specific surface area and porous structure, enabling it to adsorb carbon nanotubes. The high mechanical strength and fibrous structure of the carbon nanotubes allow them to interweave between the nano-shell powder particles, forming a network support and increasing the antibacterial properties, mechanical strength, and abrasion resistance of the shell powder. Sodium alginate is an anionic polysaccharide; its carboxyl groups can form hydrogen bonds with the hydroxyl groups on the surface of the nano-shell powder, and simultaneously form electrostatic interactions with chitosan in the Centella asiatica compound extract, allowing the components to firmly bind and form stable composite particles. The shell powder loaded with sodium alginate formed by mixing these three components enhances structural stability, improves the adhesion between fibers and functional components, and subsequently enhances the composite function of the fabric.

[0033] In summary, this application has the following beneficial effects: 1. The UHMWPE fiber prepared in this application not only retains the excellent properties of UHMWPE such as high strength and high wear resistance, but also has a long-lasting antibacterial effect due to the addition of GO / MOFs antibacterial composite material.

[0034] 2. The GO dispersed in white oil in this application exhibits significantly improved thermal stability due to the isolation from oxygen. Under processing conditions with temperatures not exceeding 300°C, GO experiences only slight weight loss, its carbon skeleton remains largely intact, and there is no significant oxidation. Its sharp edges can cause cell membrane rupture through direct puncture, and its surface rich in oxygen-containing functional groups can trigger oxidative stress responses within microorganisms, both of which lead to bacterial death and exert an antibacterial effect.

[0035] 3. In this application, Ag-MOF has a porous structure and high specific surface area, which can load and slowly release antibacterial ions, thereby exerting an antibacterial effect. Attached Figure Description

[0036] Figure 1 Stress-strain curves and TG curves of the antibacterial modified fiber prepared in Example 1.

[0037] Figure 2 SEM images of fibers prepared in Examples 1-3 and Comparative Example 1: (a) 0 wt%, (b) 0.5 wt%, (c) 1.0 wt%, (d) 1.5 wt%. Detailed Implementation

[0038] The present application will be further described in detail below with reference to the embodiments.

[0039] The raw materials used in the examples and comparative examples are all commercially available.

[0040] Preparation Example 1-1 of Centella Asiatica Complex Extract The preparation method of Centella asiatica compound extract includes the following steps: (1) 10 kg of Centella asiatica was crushed, dispersed in 25 L of deionized water, sonicated for 32 min, stirred at 93 °C for 3.5 h, filtered, and the supernatant was obtained. The supernatant was concentrated and freeze-dried at -40 °C to obtain Centella asiatica extract. (2) Disperse the Centella asiatica extract in 30L of deionized water, stir for 22min, then add 3kg of chitosan mixture, dry, grind, and obtain Centella asiatica compound extract; The preparation method of the chitosan mixture includes the following steps: 5 kg of chitosan is dispersed in 13 L of 2% acetic acid solution, 1 kg of polyvinylpyrrolidone and 3 kg of silica microspheres are added, and the mixture is stirred at 58℃ for 40 min to obtain the chitosan mixture. The mass ratio of Centella asiatica extract to chitosan mixture is 1:0.06.

[0041] Preparation Examples 1-2 The difference from preparation example 1-1 is that silica microspheres are not added in step (2).

[0042] Preparation Examples 1-3 The difference from preparation example 1-1 is that chitosan mixture is not added in step (2).

[0043] Preparation Example 2-1 of Sodium Alginate Loaded on Shell Powder The preparation method of sodium alginate loaded on shell powder includes the following steps: 8 kg of shell powder was dispersed in 20 L of 5% sodium hydroxide solution and soaked for 1.5 h. After washing with water, the powder was calcined at 510 °C for 1.5 h to obtain nano-shell powder. The nano-shell powder was dispersed in 15 L of deionized water, 2.5 kg of carbon nanotubes were added, the mixture was stirred for 35 min, filtered, and dried to obtain composite shell powder. The composite shell powder was dispersed in 16L of sodium alginate solution, stirred for 5 minutes, filtered, and dried to obtain shell powder-loaded sodium alginate; Sodium alginate solution: 2kg of sodium alginate was dispersed in 10L of deionized water and stirred at 60℃ for 20 minutes to obtain sodium alginate solution.

[0044] The mass ratio of shell powder, carbon nanotubes, and sodium alginate solution is 1:0.32:38.

[0045] Preparation Example 2-2 The difference from preparation example 2-1 is that no carbon nanotubes are added.

[0046] Preparation Examples 2-3 The difference from Preparation Example 2-1 is that sodium alginate solution is not added.

[0047] Preparation Examples 2-4 The difference from Preparation Example 2-1 is that the mass ratio of shell powder, carbon nanotubes, and sodium alginate solution is 1:0.43:35.

[0048] Preparation Examples 2-5 The difference from Preparation Example 2-1 is that the mass ratio of shell powder, carbon nanotubes, and sodium alginate solution is 1:0.08:50. Example

[0049] Example 1 A UHMWPE fiber containing GO / MOFs antibacterial composite material includes the following steps: (1) Preparation of GO / MOF antibacterial composite material: 1 kg of GO and Ag-MOF (mass ratio of GO to Ag-MOF is 1:10) were dispersed in 10 L of ethanol, sonicated for 2.5 h, filtered and dried to obtain GO / MOF antibacterial composite material; (2) Disperse 0.5 kg of GO / MOFs antibacterial composite material in 900 L of white oil, add 0.3 wt% of dispersant (fatty alcohol polyoxyethylene ether) of the total mass of the system, mechanically stir at room temperature for 30 min at a stirring rate of 180 r / min, mix with 100 kg of PE powder, heat and stir at a stirring speed of 55 r / min, temperature of 110 °C, time of 80 min to form UHMWPE swelling solution, extrude by twin screw, spin, cool and form to obtain gel fiber, and then obtain UHMWPE fiber by pre-stretching, extraction, drying and multi-stage hot stretching.

[0050] The preparation method of Ag-MOF is as follows: 57g of silver nitrate was dissolved in 2L of double-distilled water to obtain a metal solution. 1kg of 2-methylimidazole was dissolved in 10L of double-distilled water to obtain a ligand solution. The metal solution was added dropwise to the ligand solution and reacted at room temperature for 10min. The mixture was magnetically stirred until it turned milky white. The precipitate Ag-MOF was obtained by centrifugation at 12000rpm for 8min. The precipitate was washed three times with double-distilled water and dried to obtain the final product.

[0051] Twin-screw extrusion parameters: rotation speed 210 r / min, temperature segments set to 150℃, 240℃, 290℃, 280℃; spinning parameters: spinning temperature 235℃; pre-stretching parameters: nozzle stretch ratio 1.8.

[0052] Extraction parameters: White oil removal (extractant is dichloromethane, temperature is 30℃, extractant replenishment is 100kg / h, and fiber feed speed is 60m / min).

[0053] Multi-stage hot stretching parameters: three-stage and four-stage segmented stretching, stretching temperature 130℃, total stretching ratio 6.3.

[0054] Example 2 A UHMWPE fiber containing GO / MOFs antibacterial composite material differs from Example 1 in that it includes the following steps: (1) Preparation of GO / MOF antibacterial composite material: 1 kg of GO and Ag-MOF (the mass ratio of GO and Ag-MOF is 1:15) were dispersed in 10 L of ethanol, sonicated for 3 h, filtered and dried to obtain GO / MOF antibacterial composite material; (2) 1.0 kg of GO / MOFs antibacterial composite material was dispersed in 900 L of white oil, and 0.5 wt% of dispersant (fatty alcohol polyoxyethylene ether) of the total mass of the system was added. The mixture was mechanically stirred at room temperature for 30 min at a stirring rate of 200 r / min. It was then mixed with 100 kg of PE powder and heated and stirred at a stirring speed of 50 r / min, a temperature of 120 °C, and a time of 60 min to form a UHMWPE swelling solution. The solution was then extruded by a twin-screw extruder, spun, cooled and shaped to obtain gel fiber. UHMWPE fiber was then obtained by pre-stretching, extraction, drying and multi-stage hot stretching.

[0055] Twin-screw extrusion parameters: rotation speed 200 r / min, temperature segments set to 150℃, 240℃, 290℃, 280℃; spinning parameters: spinning temperature 230℃; pre-stretching parameters: nozzle stretch ratio 1.5.

[0056] Extraction parameters: white oil removal, temperature 27℃, extractant replenishment 110kg / h, fiber feed speed 50m / min.

[0057] Multi-stage hot stretching parameters: three-stage and four-stage segmented stretching, temperature 135℃, total stretching ratio 6.5.

[0058] Example 3 A UHMWPE fiber containing GO / MOFs antibacterial composite material differs from Example 1 in that it includes the following steps: (1) Preparation of GO / MOF antibacterial composite material: 1 kg of GO and Ag-MOF (the mass ratio of GO and Ag-MOF is 1:4) were dispersed in 10 L of ethanol, sonicated for 2 h, filtered and dried to obtain GO / MOF antibacterial composite material; (2) 1.5 kg of GO / MOFs antibacterial composite material was dispersed in 900 L of white oil, and 0.1 wt% of dispersant (fatty alcohol polyoxyethylene ether) of the total mass of the system was added. The mixture was mechanically stirred at room temperature for 35 min at a stirring rate of 150 r / min. It was then mixed with 100 kg of PE powder and heated and stirred at a stirring speed of 60 r / min, a temperature of 100 °C, and a time of 100 min to form a UHMWPE swelling solution. The solution was then extruded by a twin-screw extruder, spun, cooled and shaped to obtain gel fiber. UHMWPE fiber was then obtained by pre-stretching, extraction, drying and multi-stage hot stretching.

[0059] Twin-screw extrusion parameters: rotation speed 220 r / min, temperature segments set to 160℃, 230℃, 300℃, 270℃; spinning parameters: spinning temperature 240℃; pre-stretching parameters: nozzle stretch ratio 2.

[0060] Extraction parameters: white oil removal, temperature 35℃, extractant replenishment 95kg / h, fiber feed speed 65m / min.

[0061] Multi-stage hot stretching parameters: three-stage and four-stage segmented stretching, temperature 125℃, total stretching ratio 6.

[0062] Application Example 1 A composite yarn is made by spinning core-spun yarn from UHMWPE fiber obtained in Example 1 and natural fiber; the natural fiber (wool fiber) is soaked in a modifying solution for 8 minutes and then dried to obtain the treated fiber; the modifying solution includes 6 kg of modifier and 20 L of water, and the modifier is a mixture of Centella asiatica compound extract, seashell powder-loaded sodium alginate and hyaluronic acid in a mass ratio of 1:0.59:0.34.

[0063] Natural fibers are coated onto the surface of UHMWPE fibers to obtain composite yarn with a fineness of 55 Nm, and the spinning method is core-spun yarn.

[0064] The Centella asiatica compound extract was prepared in Example 1-1, and the seashell powder loaded with sodium alginate was prepared in Example 2-1.

[0065] Application Example 2 A composite yarn differs from Application Example 1 in that the natural fibers are soaked in a modifying solution for 5 minutes and then dried to obtain the treated fibers. The modifying solution includes 7 kg of modifier and 20 L of water. The modifier is a mixture of Centella asiatica compound extract, seashell powder-loaded sodium alginate, and hyaluronic acid in a mass ratio of 1:0.73:0.12.

[0066] Application Example 3 A composite yarn, which differs from Application Example 1 in that the Centella Asiatica composite extract is prepared using Examples 1-2.

[0067] Application Example 4 A composite yarn, which differs from Application Example 1 in that the Centella Asiatica composite extract is prepared using Examples 1-3.

[0068] Application Example 5 A composite yarn, which differs from Application Example 1 in that the seashell powder loaded with sodium alginate is prepared in Preparation Example 2-2.

[0069] Application Example 6 A composite yarn differs from Application Example 1 in that the seashell powder loaded with sodium alginate is prepared using Examples 2-3.

[0070] Application Example 7 A composite yarn, which differs from Application Example 1 in that the seashell powder loaded with sodium alginate is prepared in Examples 2-4.

[0071] Application Example 8 A composite yarn, which differs from Application Example 1 in that the seashell powder loaded with sodium alginate is prepared in Examples 2-5.

[0072] Comparative Example Comparative Example 1 A UHMWPE fiber containing GO / MOFs antibacterial composite material differs from Example 1 in that it does not contain MOFs.

[0073] Performance testing The performance of UHMWPE fibers containing GO / MOFs antibacterial composites prepared in Examples 1-3, Application Examples 1-8 and Comparative Example 1 was tested. The mechanical and thermal properties of the fibers were tested according to GB / T 33269-2016 "Ultra-high molecular weight polyethylene filament"; the antibacterial properties of the fibers were tested according to GB / T 20944.3-2008 "Evaluation of antibacterial properties of textiles - Part 3: Vibration method". The test results are shown in Table 1.

[0074] Table 1 Test data for the examples and comparative examples As shown in Table 1, the UHMWPE fiber fabrics containing GO / MOF antibacterial composite materials prepared in Examples 1-3 of this application exhibit good mechanical properties and thermal stability. Specifically, in Example 1, when the MOF content is 0.5%, the UHMWPE fiber achieves an inhibition rate of over 99% against Escherichia coli and Staphylococcus aureus, with a strain of 1.69% and an initial decomposition temperature of 428℃. The tensile creep and TG curves are shown below. Figure 1 (The stress-strain curve and TG curve of the antibacterial modified fiber are shown.) The addition of MOF significantly improves the antibacterial properties, creep resistance and thermal stability of UHMWPE fiber, which provides a reliable basis for subsequent fiber modification.

[0075] We also found that the elongation at break of antibacterial modified UHMWPE fibers decreased. From a theoretical perspective, a small amount of nanoparticles can act as nucleating agents, thereby increasing the crystallinity of the fiber and consequently increasing its tensile strength. However, when the MOF addition amount was 0.5% and 1.5%, the fiber tensile strengths were 28.70 cN / dtex and 27.91 cN / dtex, respectively; with increasing MOF addition, the mechanical properties decreased. Figure 2 As can be seen from the SEM images (a) 0 wt%, (b) 0.5 wt%, (c) 1.0 wt%, (d) 1.5 wt%), when the MOF content reaches 1.5%, the agglomeration phenomenon is severe, which is the main reason for the decline in fiber mechanical properties. Therefore, optimizing the dispersion process of antibacterial materials is very important.

[0076] In Application Examples 1-2, composite yarns were prepared by combining UHMWPE antibacterial modified fibers with natural fibers. Table 1 shows that Application Example 1 achieved an antibacterial rate of 99% against Escherichia coli, 99% against Staphylococcus aureus, and 98% against Candida albicans, with a strain of 0.56%, a breaking strength of 38.9 cN / dtex, and a breaking elongation of 5.66%. These performance tests were significantly better than those in Examples 1-3, indicating that Centella asiatica extract is adsorbed onto the surface of sodium alginate supported by shell powder. The sodium alginate and hyaluronic acid are mixed to form a film that wraps around the fibers, locking the active substances such as Centella asiatica extract and shell powder onto the fiber surface, forming a durable functional coating that subsequently improves the antibacterial and mechanical properties of the fabric.

[0077] In the preparation methods of the Centella asiatica compound extract in Application Examples 3-4, neither silica microspheres nor chitosan mixture was added. Table 1 shows that the antibacterial rates against *E. coli*, *Staphylococcus aureus*, and *Candida albicans*, as well as the performance in strain, tensile strength, and elongation at break in Application Examples 3-4 were inferior to those in Application Examples 1-2, but superior to those in Examples 1-3. This indicates that the Centella asiatica extract itself possesses antibacterial properties and can be loaded onto the surface of natural fibers. The silica microspheres exhibit good mechanical properties and abrasion resistance, while chitosan possesses film-forming and antibacterial properties. This results in a tight bond between the Centella asiatica extract, silica microspheres, and natural fibers, not only improving the antibacterial properties of the subsequent Centella asiatica compound extract but also enhancing the corresponding mechanical properties.

[0078] Application Examples 5-6 show the preparation methods of shell powder loaded with sodium alginate without the addition of carbon nanotubes and sodium alginate solution, while Application Examples 7-8 show the changes in the mass ratio of shell powder, carbon nanotubes, and sodium alginate solution. Table 1 shows that the performance of Application Examples 5-6 in terms of antibacterial rates against *E. coli*, *Staphylococcus aureus*, and *Candida albicans*, as well as strain, tensile strength, and elongation at break, is inferior to Application Examples 1-2 and 7, but superior to Examples 1-3. Application Example 8, on the other hand, shows superior performance in all corresponding performance tests compared to Application Examples 5-6, but inferior to Application Examples 1-2. This indicates that the carboxyl groups of sodium alginate can form hydrogen bonds with the hydroxyl groups on the surface of nano-shell powder, and simultaneously form electrostatic interactions with chitosan in the *Centella asiatica* composite extract, allowing the components to firmly bind and form stable composite particles. The shell powder loaded with sodium alginate formed after mixing these three components enhances structural stability, improves the adhesion between fibers and functional components, and subsequently enhances the composite function of the fabric.

[0079] Comparative Example 1, without MOFs, showed the following results in Table 1: 56% antibacterial rate against *Escherichia coli*, 50% against *Staphylococcus aureus*, and 48% against *Candida albicans*; strain 2.32%; tensile strength 22.7 cN / dtex; elongation at break 3.06%; initial decomposition temperature 386℃; and melting point 158.2℃. This indicates that the addition of MOFs significantly improved the antibacterial properties, creep resistance, and thermal stability of UHMWPE fibers, while the absence of MOFs significantly affected the overall performance of the fibers.

[0080] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A UHMWPE fiber containing a GO / MOF antibacterial composite material, characterized in that, Includes the following steps: (1) Preparation of GO / MOFs antibacterial composite material: GO and antibacterial MOFs were dispersed in a solvent, sonicated for 2-3 hours, filtered and dried to obtain GO / MOFs antibacterial composite material; (2) Disperse the GO / MOFs antibacterial composite material in white oil, add 0.1-0.5wt% dispersant, mechanically stir at room temperature for 30-35 min at a stirring rate of 150-200 r / min, add PE powder, mix and heat, stirring at a stirring speed of 50-60 r / min, stirring temperature of 100-120℃, stirring time of 60-100 min to form a UHMWPE swelling solution, which is then extruded by twin screws, spun, cooled and shaped to obtain gel fiber, and then pre-stretched, extracted, dried and multi-stage hot stretched to obtain UHMWPE fiber.

2. The UHMWPE fiber containing GO / MOFs antibacterial composite material according to claim 1, characterized in that, Twin-screw extrusion parameters: rotation speed 200-220 r / min, temperature segments set to 150-160℃, 230-240℃, 290-300℃, 270-280℃; spinning parameters: spinning temperature 230-240℃; pre-stretching parameters: nozzle stretch ratio 1.5-2.

3. The UHMWPE fiber containing GO / MOFs antibacterial composite material according to claim 1, characterized in that, Extraction parameters: Extraction temperature 25-35℃, fiber feed speed 50-65 m / min.

4. The UHMWPE fiber containing GO / MOFs antibacterial composite material according to claim 1, characterized in that, Multi-stage hot stretching parameters: three-stage and four-stage segmented stretching: temperature 125-145℃, total stretching ratio 5.5-7.

5. The application of UHMWPE fiber containing GO / MOFs antibacterial composite material as described in claims 1-4 in composite yarn.

6. A composite yarn according to claim 5, characterized in that, The core-spun yarn is made from the UHMWPE fiber and natural fiber; the natural fiber is soaked in the modification solution for 5-8 minutes and then dried to obtain the treated fiber; the modification solution includes a modifier and water, and the modifier is a mixture of Centella asiatica compound extract, seashell powder-loaded sodium alginate, and hyaluronic acid in a mass ratio of 1:0.59-0.73:0.12-0.

34.

7. A composite yarn according to claim 6, characterized in that, The preparation method of the Centella asiatica compound extract includes the following steps: (1) Pulverize Centella asiatica, disperse it in deionized water, sonicate for 30-35 min, stir at 90-95℃ for 3-4 h, filter, obtain supernatant, concentrate, freeze dry to obtain Centella asiatica extract; (2) Disperse the Centella asiatica extract in deionized water, stir for 20-25 min, then add chitosan mixture, dry, grind to obtain Centella asiatica complex extract; The method for preparing the chitosan mixture includes the following steps: dispersing chitosan in an acetic acid solution, adding polyvinylpyrrolidone and silica microspheres, and stirring at a temperature of 55-60℃ for 30-45 minutes to obtain the chitosan mixture.

8. A composite yarn according to claim 6, characterized in that, The method for preparing the seashell powder loaded with sodium alginate includes the following steps: Disperse shell powder in sodium hydroxide solution, soak for 1-2 hours, wash with water, calcine at 500-510℃ for 1-2 hours to obtain nano-shell powder, disperse nano-shell powder in deionized water, add carbon nanotubes, stir for 30-35 minutes, filter, dry to obtain composite shell powder. The composite shell powder was dispersed in a sodium alginate solution, stirred for 3-5 minutes, filtered, and dried to obtain shell powder loaded with sodium alginate.

9. A composite yarn according to claim 8, characterized in that, The mass ratio of the shell powder, carbon nanotubes, and sodium alginate solution is 1:0.32-0.43:35-38.

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