Wear-resistant and high-temperature-resistant polyester fiber and preparation method thereof

Abstract

The application discloses a wear-resistant and high-temperature-resistant polyester fiber and a preparation method thereof, and belongs to the technical field of polyester processing, and is used for solving the technical problem that the wear resistance and high-temperature resistance of the polyester fiber in the prior art need to be further improved, and specifically comprises the following steps: adding modified PET, modified filler and auxiliary additive into a double-screw extruder, melt-extruding, spinning, and obtaining a polyester fiber precursor; the application is characterized in that an epoxy group is modified on a carboxylated carbon nanotube through a free radical polymerization reaction to obtain a modified filler, and the modified filler, the auxiliary additive and the modified PET are melt-spun together to obtain the polyester fiber precursor, a modified antibacterial agent is prepared through a coprecipitation method, an antibacterial liquid is further prepared, and the polyester fiber precursor is immersed in the antibacterial liquid to obtain the polyester fiber, so that the wear resistance and high-temperature resistance of the polyester fiber are improved, and the antibacterial performance of the polyester fiber is also improved.

Description

Technical Field

[0001] This invention relates to the field of polyester processing technology, specifically to a wear-resistant and high-temperature-resistant polyester fiber and its preparation method. Background Technology

[0002] Polyester fiber (polyethylene terephthalate fiber, PET) is widely used in clothing, industrial fabrics, geotextiles and high-performance composite materials due to its excellent mechanical properties, chemical resistance and molding and processing performance.

[0003] With the increasing demands on material performance in various applications, especially in harsh environments such as high temperature and high wear, the abrasion resistance and thermal stability of traditional polyester fibers have gradually become important factors limiting their further development. To improve their abrasion resistance and high temperature resistance, researchers have carried out a variety of modification methods, such as blending reinforcement, nanofiller filling, hot stretching orientation, and surface coating treatment. These methods have advantages such as mature technology, controllable cost, and ease of large-scale application, and have become important means to improve the overall performance of polyester.

[0004] In the existing technology, although the above-mentioned modification methods improve the wear resistance and heat resistance of polyester fibers to a certain extent, there are still many shortcomings: First, nanoparticles are prone to agglomeration in the filler blending method, resulting in uneven dispersion, which in turn affects the continuity and mechanical stability of the fiber. Second, although the surface coating can improve wear resistance in the short term, its bonding force with the matrix is ​​limited and it is easy to fall off during friction or washing, reducing durability. In addition, the added reinforcing filler has poor interfacial compatibility with the PET matrix and weak interfacial bonding force.

[0005] To address this technical deficiency, a solution is proposed. Summary of the Invention

[0006] The purpose of this invention is to provide a wear-resistant and high-temperature-resistant polyester fiber and its preparation method, in order to solve the technical problem that the wear resistance and high-temperature resistance of polyester fibers in the prior art need to be further improved.

[0007] The objective of this invention can be achieved through the following technical solution: a method for preparing wear-resistant and high-temperature-resistant polyester fibers, comprising the following steps:

[0008] S1. Place terephthalic acid, ethylene glycol, 1,4-butenediol and catalyst in a reaction vessel under nitrogen atmosphere and stir. Heat to 250-260℃ and keep the reaction at this temperature for 2-3 hours to obtain the prepolymer.

[0009] S2. Place the prepolymer in a nitrogen-protected reactor and stir. Evacuate the reactor to a vacuum, add trimethyl phosphate, heat to 280-290℃, and keep the temperature for 4-6 hours. Then, perform post-treatment to obtain modified PET.

[0010] The reaction formula for the preparation of modified PET is:

[0011]

[0012] The reaction principle for the preparation of modified PET is as follows:

[0013] During the reaction, under high temperature and the action of a catalyst, phthalic acid, ethylene glycol and 1,4-butenediol undergo esterification, releasing water and partially condensing to form a linear prepolymer. Trimethyl phosphate is added as a stabilizer, and the temperature is further increased and a vacuum is drawn to promote the condensation reaction to the right, increasing the molecular weight and obtaining modified PET.

[0014] S3. Modified PET, modified filler and auxiliary additives are added to a twin-screw extruder, melt extruded and spun to obtain polyester fiber precursor;

[0015] The reaction principle for preparing polyester fibers is as follows:

[0016] During the reaction, under high temperature, the hydroxyl groups of the modified PET undergo a ring-opening reaction with the epoxy functional groups in the modified filler, forming covalent bonds. After melt spinning, polyester fibers are obtained.

[0017] S4. The polyester fiber precursor is immersed in an antibacterial solution and then post-treated to obtain polyester fiber.

[0018] The reaction principle for preparing polyester fibers is as follows:

[0019] During the reaction, under the irradiation of ultraviolet light, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide is cleaved into free radicals, which initiate a mercapto-olefin click reaction between the unsaturated double bonds of the olefins in the polyester fiber precursor and the antibacterial solution, thus obtaining polyester fibers.

[0020] Further, in step S1, the weight ratio of terephthalic acid, ethylene glycol, 1,4-butenediol and catalyst is 6-8:2-4:1-2:0.5-1, and the catalyst is antimony trioxide; in step S2, the weight ratio of prepolymer and trimethyl phosphate is 8-10:0.2-0.4, and the post-processing step includes: after the reaction is completed, after the reaction system cools to room temperature, the reaction solution is transferred to a rotary evaporator at a temperature of 80-100℃, and distilled under reduced pressure until no liquid is collected to obtain modified PET;

[0021] Further, in step S3, the weight ratio of the modified PET, modified filler, and auxiliary additives is 60-80:10-15:5-10. The auxiliary additives are composed of antioxidants, lubricants, antistatic agents, and UV absorbers in a mass ratio of 1:2:1:3. The antioxidants are one or more of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], N,N'-diphenyl-p-phenylenediamine, and N,N'-diphenyl-p-phenylenediamine. The lubricants are one or more of oleamide, paraffin wax, and polyethylene wax. The antistatic agents are one or more of amide phosphate, tricresyl phosphate, and alkylphenol polyoxyethylene ether. The UV absorbers are one or more of 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole, bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate, and 2-hydroxy-4-methoxybenzophenone.

[0022] Furthermore, the temperatures of the eight temperature zones of the twin-screw extruder from the feed inlet to the discharge outlet are 280℃, 280℃, 285℃, 285℃, 295℃, 295℃, 300℃, and 300℃ respectively. The main engine speed of the twin-screw extruder is 80-120 rpm, and the pressure is 100-150 bar.

[0023] Furthermore, the spinning operation steps include: extruding the melt through a spinneret and transferring it to a side-blowing chamber, where it is air-cooled and solidified to obtain a polyester fiber precursor. The spinneret has circular channels with a mesh count of 36-48 and an aperture of 0.1-0.3 mm, while the spinning pressure is 80-120 bar. The atmosphere in the side-blowing chamber is air, with a relative humidity of 30-40% and a temperature of 20-30℃, while the flow rate is maintained at 5-10 m / s.

[0024] Further, in step S4, the impregnation ratio is 1:30-35, and the impregnation operation includes the following steps: impregnating the polyester fiber precursor in an antibacterial solution for 10-15 minutes, removing it, and irradiating it under a UV lamp for 1-3 minutes. The wavelength of the UV lamp is 395-400 nm, the irradiation distance is 10-15 cm, and the power is 100-500 mW / cm². The post-treatment step includes: after the reaction is completed, placing the fiber in an oven at a temperature of 40-50℃ and drying it to a constant weight to obtain polyester fiber.

[0025] Furthermore, in step S3, the modified filler is prepared by the following steps:

[0026] A1. Styrene, ethyl acetate, azobisisobutyronitrile and glycidyl methacrylate were placed in a reaction vessel and stirred. The reaction vessel was heated to 65-75℃, maleic anhydride was added, and the reaction was kept at the temperature for 1-2 hours. After post-treatment, intermediate I was obtained.

[0027] The reaction formula for the preparation of intermediate I is as follows:

[0028]

[0029] The reaction principle for the preparation of intermediate I is as follows:

[0030] During the reaction, under the action of high temperature and initiator, maleic anhydride, styrene and glycidyl methacrylate undergo free radical polymerization to obtain intermediate I.

[0031] A2. Add carboxylated carbon nanotubes to a ball mill and ball mill them to obtain activated carbon nanotubes;

[0032] A3. Place activated carbon nanotubes and acetone in a reaction vessel, stir for 20-30 minutes, add intermediate I, heat to 45-55℃, keep the temperature for 4-6 hours, and then perform post-treatment to obtain the modified filler.

[0033] The reaction principle for preparing modified fillers is as follows:

[0034] During the reaction, activated carbon nanotubes are uniformly dispersed in acetone. After the addition of intermediate I, the maleic anhydride in intermediate I undergoes a ring-opening reaction with the carboxyl and hydroxyl groups on the surface of the activated carbon nanotubes to form a covalent graft structure, thus obtaining an epoxy-modified filler.

[0035] Further, in step A1, the ratio of styrene, ethyl acetate, azobisisobutyronitrile, glycidyl methacrylate, and maleic anhydride is 4-6g:80-100mL:0.5-1g:2-4g:1-2g. The post-processing step includes: after the reaction is complete, wait for the reaction system to cool to room temperature, add the reaction solution to 200-300mL of petroleum ether to precipitate, filter, wash the filter cake 2-3 times with petroleum ether, transfer it to an oven at 30-40℃, and dry it to constant weight to obtain intermediate I; in step A2, the ball milling operation includes: activating sodium carbon... The rice nanotubes are added to a planetary ball mill with 5-10mm stainless steel grinding balls at a ball-to-material ratio of 10:1. The milling speed is set to 400-500 rpm for 1-2 hours. The nanotubes are then passed through a 300-400 mesh sieve to obtain activated carbon nanotubes. In step A3, the ratio of activated carbon nanotubes, acetone, and intermediate I is 1-2g:50-100mL:5-7g. The post-processing steps include: after the reaction is complete, the reaction system is cooled to room temperature, filtered, and the filter cake is washed 2-3 times with deionized water and ethanol. The filter cake is then transferred to an oven at 50-60℃ and dried to constant weight to obtain the modified filler.

[0036] The method for preparing the activated carbon nanotubes is as follows: carboxylated carbon nanotubes are added to a planetary ball mill, stainless steel grinding balls of 5-10 mm are added, the ball-to-material ratio is 10:1, the rotation speed is set to 400-500 rpm, the ball milling is performed for 1-2 hours, and the material is passed through a 300-400 mesh sieve to obtain activated carbon nanotubes.

[0037] In step S4, the method for preparing the antibacterial solution includes:

[0038] B1. Place β-cyclodextrin, deionized water and ethanol in a reaction vessel and stir. Heat the reaction vessel to 55-65℃ and keep it at that temperature for 15-30 min. Slowly add tea polyphenols and react in the dark for 1-2 h. Cool down to 0-5℃ and react in the dark for 10-12 h. Post-treatment yields the modified antibacterial agent.

[0039] The preparation reaction principle of the modified antibacterial agent is as follows:

[0040] During the reaction, β-cyclodextrin is a cyclic polysaccharide molecule with a hydrophilic outer shell and a hydrophobic inner cavity, possessing molecular inclusion ability. Tea polyphenols are natural antibacterial components, containing a large number of phenolic hydroxyl groups and phenyl groups within their molecules. The benzene ring of tea polyphenols enters the hydrophobic inner cavity of β-cyclodextrin, and the external hydroxyl groups of β-cyclodextrin and the phenolic hydroxyl groups of tea polyphenols form inclusion complexes through hydrogen bonding. The light-protected reaction is to avoid the oxidative decomposition of tea polyphenols, and the low temperature can promote the self-assembly and precipitation of the inclusion complex to form crystals, thus obtaining a modified antibacterial agent.

[0041] B2. Place the modified antibacterial agent, γ-mercaptopropyltriethoxysilane, ethanol and deionized water in a reaction vessel and stir. Add saturated ammonia water, heat the reaction vessel to 45-55℃, and keep it at this temperature for 1-2 hours. Then, perform post-treatment to obtain the antibacterial solution.

[0042] The reaction principle for preparing the antibacterial solution is as follows:

[0043] During the reaction, the silicon-oxygen bond of γ-mercaptopropyltriethoxysilane can be hydrolyzed into silanol under deionized water and heating conditions. The silanol further undergoes a condensation reaction with the hydroxyl group in the modified antibacterial agent, and the antibacterial solution is obtained through post-treatment.

[0044] Further, in step B1, the ratio of β-cyclodextrin, deionized water, ethanol, and tea polyphenols is 2-4g:20-30mL:15-20mL:2-4g. The post-processing steps include: after the reaction is complete, the reaction system is cooled to room temperature, filtered, the filter cake is washed 2-3 times with anhydrous ethanol, transferred to an oven at 35-45℃, and dried to constant weight to obtain the modified antibacterial agent; in step B2, the modified antibacterial agent, γ-mercaptopropyltriethoxysilane, The ratio of ethanol, deionized water, and saturated ammonia is 2-4g:0.5-1g:50-80mL:5-10mL:1-2mL. The post-processing steps include: after the reaction is completed, wait for the reaction to cool to room temperature, filter, wash the filter cake 2-3 times with deionized water and ethanol, transfer it to an oven at 50-60℃, dry it to constant weight, take out the product and add it to 150-200mL of ethanol-water solution with a volume ratio of 2:1, sonicate until the product dissolves, and obtain the antibacterial solution.

[0045] The present invention also proposes a wear-resistant and high-temperature resistant polyester fiber, which is prepared by the above-mentioned method for preparing a wear-resistant and high-temperature resistant polyester fiber.

[0046] The present invention has the following beneficial effects:

[0047] 1. This invention prepares intermediate I through free radical polymerization. Then, intermediate I is covalently grafted onto activated carbon nanotubes via an anhydride ring-opening reaction to obtain a modified filler. The carboxylated carbon nanotubes are ball-milled to break down the bundled aggregates, exfoliating them into finer, more dispersed single tubes or small bundles, increasing the exposed surface area and exposing the carboxyl groups or defect sites originally buried inside. This provides more reactive sites for anhydride ring-opening. Further covalent grafting of intermediate I with anhydride ring-opening enables the modified filler to... The modified PET matrix achieves more uniform and stable dispersion, avoiding agglomeration and improving the mechanical properties of polyester fibers. Furthermore, carbon nanotubes have excellent mechanical strength, thermal stability, and thermal conductivity, which can form a skeletal support in the polymer matrix, dispersing external impacts, reducing surface wear and scratches, and improving the wear resistance of polyester fibers. The excellent thermal stability and high thermal conductivity of carbon nanotubes help to hinder the thermal movement of polyester chain segments, improve the heat distortion temperature and thermal stability of the material, reduce the risk of deformation at high temperatures, and improve the high-temperature resistance of polyester fibers.

[0048] 2. This invention involves preparing a modified filler with epoxy groups, which is then melt-extruded and used in conjunction with modified PET and auxiliary additives to prepare a polyester fiber precursor. During the melting process, the epoxy groups in the modified filler undergo a ring-opening reaction with the hydroxyl groups in the modified PET, forming covalent bonds. This improves the interfacial bonding between the modified filler and the modified PET, further enhancing the wear resistance and mechanical properties of the polyester fiber. Simultaneously, the modified filler not only acts as a reinforcing agent in the PET matrix but also exhibits a good nucleation effect. During polyester crystallization, the abundant functional groups on the surface of the carbon nanotubes in the modified filler can serve as heterogeneous nucleation centers, inducing the ordered arrangement of the modified PET molecular chains, thereby accelerating the crystallization rate and increasing the crystallinity. The uniform dispersion of the carbon nanotubes makes the crystallization process more uniform and stable, contributing to the formation of a smaller, more uniformly distributed grain structure. The fine and dense crystal structure can effectively absorb and disperse external stress, hindering the initiation and propagation of cracks during stress, significantly improving the material's impact resistance and toughness.

[0049] 3. This invention utilizes a co-precipitation method, employing β-cyclodextrin as an inclusion compound and tea polyphenols as a natural antibacterial substance, to prepare a modified antibacterial agent through physical and hydrogen bonding interactions. A mercaptosilane coupling agent is then externally modified into the modified antibacterial agent. The agent is uniformly mixed with a solvent to obtain the antibacterial agent. A polyester fiber precursor is impregnated in the antibacterial solution and further subjected to a mercapto-olefin click reaction with the effective substances in the antibacterial solution under ultraviolet light. After drying, polyester fibers are obtained. Tea polyphenols, as a natural antibacterial agent, possess broad-spectrum antibacterial and microbial growth-inhibiting functions. The inclusion of β-cyclodextrin stabilizes its structure and allows for sustained release of its activity. The formation of covalent bonds through mercapto-olefin clicks stably grafts the antibacterial components onto the fiber surface, improving the antibacterial properties of the polyester fiber. Detailed Implementation

[0050] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] The carboxylated carbon nanotubes used in this invention have a diameter of 10-50 nm, a length of 5-20 μm, and are multi-walled. The tea polyphenols used in this invention have a molecular weight of 281.36, comply with national standards, and have a polyphenol content of ≥98%.

[0052] Example 1

[0053] This embodiment provides a method for preparing a wear-resistant and high-temperature-resistant modified filler for polyester fibers, including the following steps:

[0054] Step I: Preparation of intermediate I

[0055] Weigh out 40g of styrene, 800mL of ethyl acetate, 5g of azobisisobutyronitrile and 20g of glycidyl methacrylate and place them in a reaction vessel and stir. Heat the reaction vessel to 65℃, add 10g of maleic anhydride, and keep the reaction at this temperature for 1h. After the reaction is complete, wait for the reaction system to cool to room temperature, add the reaction solution to 2000mL of petroleum ether to precipitate, filter, wash the filter cake twice with petroleum ether, transfer it to an oven at 30℃ and dry it to constant weight to obtain intermediate I.

[0056] Step II: Preparation of activated carbon nanotubes

[0057] Carboxylated carbon nanotubes were added to a planetary ball mill with 5mm stainless steel grinding balls. The ball-to-material ratio was 10:1, the rotation speed was set to 400 rpm, and the milling was carried out for 1 hour. The resulting material was then passed through a 300-mesh sieve to obtain activated carbon nanotubes.

[0058] Step III: Preparation of modified fillers

[0059] Weigh 10g of activated carbon nanotubes and 500mL of acetone and place them in a reaction vessel. Stir for 20min, add 50g of intermediate I, heat to 45℃, and keep the temperature for 4h. After the reaction is complete, wait for the reaction system to cool to room temperature, filter, wash the filter cake twice with deionized water and ethanol, transfer it to an oven at 50℃, and dry it to constant weight to obtain the modified filler.

[0060] Example 2

[0061] This embodiment provides a method for preparing a wear-resistant and high-temperature-resistant modified filler for polyester fibers, including the following steps:

[0062] Step I: Preparation of intermediate I

[0063] Weigh out 50g of styrene, 900mL of ethyl acetate, 7g of azobisisobutyronitrile and 30g of glycidyl methacrylate and place them in a reaction vessel and stir. Heat the reaction vessel to 70℃, add 15g of maleic anhydride, and keep the reaction at this temperature for 1.5h. After the reaction is complete, wait for the reaction system to cool to room temperature, add the reaction solution to 2500mL of petroleum ether to precipitate, filter, wash the filter cake twice with petroleum ether, transfer it to an oven at 35℃ and dry it to constant weight to obtain intermediate I.

[0064] Step II: Preparation of activated carbon nanotubes

[0065] Carboxylated carbon nanotubes were added to a planetary ball mill with 7mm stainless steel grinding balls. The ball-to-material ratio was 10:1, the rotation speed was set to 450rpm, and the milling was carried out for 1.5 hours. The nanotubes were then passed through a 300-mesh sieve to obtain activated carbon nanotubes.

[0066] Step III: Preparation of modified fillers

[0067] Weigh 15g of activated carbon nanotubes and 750mL of acetone and place them in a reaction vessel. Stir for 25min, add 60g of intermediate I, heat to 50℃, and keep the temperature for 5h. After the reaction is complete, wait for the reaction system to cool to room temperature, filter, wash the filter cake three times with deionized water and ethanol, transfer it to an oven at 55℃, and dry it to constant weight to obtain the modified filler.

[0068] Example 3

[0069] This embodiment provides a method for preparing a wear-resistant and high-temperature-resistant modified filler for polyester fibers, including the following steps:

[0070] Step I: Preparation of intermediate I

[0071] Weigh out 60g of styrene, 1000mL of ethyl acetate, 10g of azobisisobutyronitrile and 40g of glycidyl methacrylate and place them in a reaction vessel and stir. Heat the reaction vessel to 75℃, add 20g of maleic anhydride, and keep the reaction at this temperature for 2 hours. After the reaction is complete, wait for the reaction system to cool to room temperature, add the reaction solution to 3000mL of petroleum ether to precipitate the precipitate, filter, wash the filter cake three times with petroleum ether, transfer it to an oven at 40℃ and dry it to constant weight to obtain intermediate I.

[0072] Step II: Preparation of activated carbon nanotubes

[0073] Carboxylated carbon nanotubes were added to a planetary ball mill with 10mm stainless steel grinding balls. The ball-to-material ratio was 10:1, the rotation speed was set to 500 rpm, and the milling was carried out for 2 hours. The resulting material was then passed through a 400-mesh sieve to obtain activated carbon nanotubes.

[0074] Step III: Preparation of modified fillers

[0075] Weigh 20g of activated carbon nanotubes and 1000mL of acetone and place them in a reaction vessel. Stir for 30min, add 70g of intermediate I, heat to 55℃, and keep the temperature for 6h. After the reaction is complete, wait for the reaction system to cool to room temperature, filter, wash the filter cake three times with deionized water and ethanol, transfer it to an oven at 60℃, and dry it to constant weight to obtain the modified filler.

[0076] Example 4

[0077] This embodiment provides a method for preparing a modified filler liquid for wear-resistant and high-temperature-resistant polyester fibers, comprising the following steps:

[0078] Step ①: Preparation of modified antibacterial agent

[0079] Weigh out 20g of β-cyclodextrin, 200mL of deionized water and 150mL of ethanol and place them in a reaction vessel. Stir the reaction vessel and heat it to 55℃. Keep the temperature for 15min. Slowly add 20g of tea polyphenols and react in the dark for 1h. Cool down to 0℃ and react in the dark for 10h. After the reaction is complete, wait for the reaction system to cool to room temperature, filter it, wash the filter cake twice with anhydrous ethanol, transfer it to an oven at 35℃ and dry it to constant weight to obtain the modified antibacterial agent.

[0080] Step 2: Preparation of antibacterial solution

[0081] Weigh out 20g of modified antibacterial agent, 5g of γ-mercaptopropyltriethoxysilane, 500mL of ethanol and 50mL of deionized water and place them in a reaction vessel and stir. Add 10mL of saturated ammonia water, heat the reaction vessel to 45℃ and keep it at that temperature for 1h. After the reaction is complete, wait for the reaction to cool to room temperature, filter, wash the filter cake twice with deionized water and ethanol, transfer it to an oven at 50℃ and dry it to constant weight. Take out the product and add it to 1500mL of ethanol-water solution with a volume ratio of 2:1. Sonicate until the product dissolves to obtain the antibacterial solution.

[0082] Example 5

[0083] This embodiment provides a method for preparing a modified filler liquid for wear-resistant and high-temperature-resistant polyester fibers, comprising the following steps:

[0084] Step ①: Preparation of modified antibacterial agent

[0085] Weigh out 30g of β-cyclodextrin, 250mL of deionized water and 170mL of ethanol and place them in a reaction vessel. Stir the reaction vessel and heat it to 60℃. Keep the temperature for 20min. Slowly add 30g of tea polyphenols and react in the dark for 1.5h. Cool down to 3℃ and react in the dark for 11h. After the reaction is complete, wait for the reaction system to cool to room temperature, filter it, wash the filter cake three times with anhydrous ethanol, transfer it to an oven at 40℃ and dry it to constant weight to obtain the modified antibacterial agent.

[0086] Step 2: Preparation of antibacterial solution

[0087] Weigh out 30g of modified antibacterial agent, 7g of γ-mercaptopropyltriethoxysilane, 650mL of ethanol and 80mL of deionized water and place them in a reaction vessel and stir. Add 15mL of saturated ammonia water, heat the reaction vessel to 50℃, and keep it at that temperature for 1.5h. After the reaction is complete, wait for the reaction to cool to room temperature, filter, wash the filter cake three times with deionized water and ethanol, transfer it to an oven at 55℃ and dry it to constant weight. Take out the product and add it to 1750mL of ethanol-water solution with a volume ratio of 2:1. Sonicate until the product dissolves to obtain the antibacterial solution.

[0088] Example 6

[0089] This embodiment provides a method for preparing a modified filler liquid for wear-resistant and high-temperature-resistant polyester fibers, comprising the following steps:

[0090] Step ①: Preparation of modified antibacterial agent

[0091] Weigh out 40g of β-cyclodextrin, 300mL of deionized water and 200mL of ethanol and place them in a reaction vessel. Stir the reaction vessel and heat it to 65℃. Keep the temperature for 30min. Slowly add 40g of tea polyphenols and react in the dark for 2h. Cool down to 5℃ and react in the dark for 12h. After the reaction is complete, wait for the reaction system to cool to room temperature, filter it, wash the filter cake three times with anhydrous ethanol, transfer it to an oven at 45℃ and dry it to constant weight to obtain the modified antibacterial agent.

[0092] Step 2: Preparation of antibacterial solution

[0093] Weigh out 40g of modified antibacterial agent, 10g of γ-mercaptopropyltriethoxysilane, 800mL of ethanol and 100mL of deionized water and place them in a reaction vessel and stir. Add 20mL of saturated ammonia water, heat the reaction vessel to 55℃ and keep it at that temperature for 2h. After the reaction is complete, wait for the reaction to cool to room temperature, filter, wash the filter cake three times with deionized water and ethanol, transfer it to an oven at 60℃ and dry it to constant weight. Take out the product and add it to 2000mL of ethanol-water solution with a volume ratio of 2:1, and sonicate until the product dissolves to obtain the antibacterial solution.

[0094] Example 7

[0095] This embodiment provides a method for preparing modified PET as a modified filler for wear-resistant and high-temperature-resistant polyester fibers, including the following steps:

[0096] Step (1) Preparation of prepolymer

[0097] Weigh out 80g of terephthalic acid, 40g of ethylene glycol, 20g of 1,4-butenediol and 10g of antimony trioxide and place them in a reaction vessel under nitrogen atmosphere protection. Stir the mixture, heat it to 260℃, and keep it at that temperature for 3 hours to obtain the prepolymer.

[0098] Step 2: Preparation of modified PET

[0099] Weigh 100g of prepolymer and place it in a nitrogen-protected reactor and stir. Evacuate to a vacuum of 0.01kPa. Add 4g of trimethyl phosphate, heat to 290℃, and maintain the temperature for 6 hours. After the reaction is complete, wait for the reaction system to cool to room temperature, transfer the reaction solution to a rotary evaporator at 100℃, and distill under reduced pressure until no liquid is collected to obtain modified PET.

[0100] Example 8

[0101] This embodiment provides a method for preparing modified PET as a modified filler for wear-resistant and high-temperature-resistant polyester fibers, including the following steps:

[0102] Step (1) Preparation of prepolymer

[0103] Weigh out 70g of terephthalic acid, 30g of ethylene glycol, 15g of 1,4-butenediol and 7g of antimony trioxide and place them in a reaction vessel under nitrogen atmosphere protection. Stir the mixture, heat it to 255℃, and keep it at that temperature for 2.5h to obtain the prepolymer.

[0104] Step 2: Preparation of modified PET

[0105] Weigh 90g of the prepolymer and place it in a nitrogen-protected reactor. Stir the mixture and evacuate it to a vacuum of 0.08kPa. Add 3g of trimethyl phosphate and heat it to 285℃. Keep the temperature for 5 hours. After the reaction is complete, wait for the reaction system to cool to room temperature and transfer the reaction solution to a rotary evaporator at 90℃. Distill under reduced pressure until no liquid is collected to obtain modified PET.

[0106] Example 9

[0107] This embodiment provides a method for preparing modified PET as a modified filler for wear-resistant and high-temperature-resistant polyester fibers, including the following steps:

[0108] Step (1) Preparation of prepolymer

[0109] Weigh out 80g of terephthalic acid, 40g of ethylene glycol, 20g of 1,4-butenediol and 10g of antimony trioxide and place them in a reaction vessel under nitrogen atmosphere protection. Stir the mixture, heat it to 260℃, and keep it at that temperature for 3 hours to obtain the prepolymer.

[0110] Step 2: Preparation of modified PET

[0111] Weigh 100g of prepolymer and place it in a nitrogen-protected reactor and stir. Evacuate to a vacuum of 0.13kPa. Add 4g of trimethyl phosphate, heat to 290℃, and keep the temperature for 6 hours. After the reaction is complete, wait for the reaction system to cool to room temperature, transfer the reaction solution to a rotary evaporator at 100℃, and distill under reduced pressure until no liquid is collected to obtain modified PET.

[0112] Example 10

[0113] This embodiment provides a method for preparing a wear-resistant and high-temperature-resistant modified filler for polyester fibers, including the following steps:

[0114] Step 10: Preparation of polyester fiber precursor

[0115] N,N'-diphenyl-p-phenylenediamine, polyethylene wax, alkylphenol polyoxyethylene ether, and bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate were mixed evenly in a mass ratio of 1:2:1:3 to obtain an auxiliary additive, which was then set aside.

[0116] The modified PET prepared in Example 7, the modified filler and auxiliary additives prepared in Example 1 were added to a twin-screw extruder at a mass ratio of 60:10:5 and melt-extruded. The melt was then transferred to a side-blowing chamber after being extruded through a spinneret and air-cooled for curing to obtain a polyester fiber precursor.

[0117] The temperatures of the eight temperature zones of the twin-screw extruder from the feed inlet to the discharge outlet are 280℃, 280℃, 285℃, 285℃, 295℃, 295℃, 300℃, and 300℃ respectively. The main motor speed of the twin-screw extruder is 80 rpm, and the pressure is 100 bar.

[0118] The spinneret has circular channels with a mesh count of 36 and an aperture of 0.1 mm. The spinneret pressure is 80 bar. The side blowing chamber has an air atmosphere with a relative humidity of 30% and a temperature of 20°C, while the flow rate is maintained at 10 m / s.

[0119] Step 10: Preparation of polyester fibers

[0120] The polyester fiber precursor was immersed in the antibacterial solution prepared in Example 4 for 10 min. After immersion, it was removed and irradiated under a UV lamp for 1 min. The UV lamp had a wavelength of 395 nm, an irradiation distance of 10 cm, and a power of 100 mW / cm². After the reaction was completed, the fiber was placed in an oven at 40 °C and dried to constant weight to obtain polyester fiber.

[0121] Example 11

[0122] This embodiment provides a method for preparing a wear-resistant and high-temperature-resistant modified filler for polyester fibers, including the following steps:

[0123] Step 10: Preparation of polyester fiber precursor

[0124] N,N'-diphenyl-p-phenylenediamine, polyethylene wax, alkylphenol polyoxyethylene ether, and bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate were mixed evenly in a mass ratio of 1:2:1:3 to obtain an auxiliary additive, which was then set aside.

[0125] The modified PET prepared in Example 8, the modified filler and auxiliary additives prepared in Example 2 were added to a twin-screw extruder at a mass ratio of 70:12:8 and melt-extruded. The melt was extruded through a spinneret and then transferred to a side-blowing chamber. After air-cooling and solidification, a polyester fiber precursor was obtained.

[0126] The temperatures of the eight temperature zones of the twin-screw extruder from the feed inlet to the discharge outlet are 280℃, 280℃, 285℃, 285℃, 295℃, 295℃, 300℃, and 300℃ respectively. The main motor speed of the twin-screw extruder is 100 rpm, and the pressure is 125 bar.

[0127] The spinneret has circular channels with a mesh count of 48 and an aperture of 0.2 mm. The spinneret pressure is 100 bar. The side blowing chamber has an air atmosphere with a relative humidity of 35% and a temperature of 25°C, while the flow rate is maintained at 7 m / s.

[0128] Step 10: Preparation of polyester fibers

[0129] The polyester fiber precursor was immersed in the antibacterial solution prepared in Example 5 for 12 minutes. After immersion, it was removed and irradiated under a UV lamp for 2 minutes. The UV lamp had a wavelength of 395 nm, an irradiation distance of 12 cm, and a power of 300 mW / cm². After the reaction was completed, the fiber was placed in an oven at 45°C and dried to constant weight to obtain polyester fiber.

[0130] Example 12

[0131] This embodiment provides a method for preparing a wear-resistant and high-temperature-resistant modified filler for polyester fibers, including the following steps:

[0132] Step 10: Preparation of polyester fiber precursor

[0133] N,N'-diphenyl-p-phenylenediamine, polyethylene wax, alkylphenol polyoxyethylene ether, and bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate were mixed evenly in a mass ratio of 1:2:1:3 to obtain an auxiliary additive, which was then set aside.

[0134] The modified PET prepared in Example 9, the modified filler and auxiliary additives prepared in Example 3 were added to a twin-screw extruder at a mass ratio of 80:15:10 and melt-extruded. The melt was extruded through a spinneret and then transferred to a side-blowing chamber. After air-cooling and solidification, a polyester fiber precursor was obtained.

[0135] The temperatures of the eight temperature zones of the twin-screw extruder from the feed inlet to the discharge outlet are 280℃, 280℃, 285℃, 285℃, 295℃, 295℃, 300℃, and 300℃ respectively. The main motor speed of the twin-screw extruder is 120 rpm, and the pressure is 150 bar.

[0136] The spinneret has circular channels with a mesh count of 48 and an aperture of 0.3 mm. The spinneret pressure is 120 bar. The side blowing chamber has an air atmosphere with a relative humidity of 40% and a temperature of 30°C, while the flow rate is maintained at 10 m / s.

[0137] Step 10: Preparation of polyester fibers

[0138] The polyester fiber precursor was immersed in the antibacterial solution prepared in Example 6 for 15 minutes. After immersion, it was removed and irradiated under a UV lamp for 3 minutes. The UV lamp had a wavelength of 400 nm, an irradiation distance of 15 cm, and a power of 500 mW / cm². After the reaction was completed, the fiber was placed in an oven at 50°C and dried to constant weight to obtain polyester fiber.

[0139] Comparative Example 1

[0140] The difference between this comparative example and Example 12 is that, in step ⒜, when preparing the polyester fiber precursor, carboxylated carbon nanotubes are used in an equal amount to replace the modified filler.

[0141] Comparative Example 2

[0142] The difference between this comparative example and Example 12 is that the addition of modified filler is omitted in step ⒜ when preparing the polyester fiber precursor.

[0143] Comparative Example 3

[0144] The difference between this comparative example and Example 12 is that polyester fiber precursor is used in place of polyester fiber in equal amounts.

[0145] Performance testing:

[0146] The tensile strength of the polyester fibers prepared in Examples 10-12 and Comparative Examples 1-3 was tested in accordance with the standard GB / T 14337-2008 "Test Method for Tensile Properties of Chemical Fibers (Short Fibers)".

[0147] The volumetric abrasion of the polyester fibers prepared in Examples 10-12 and Comparative Examples 1-3 was tested in accordance with the standard GB / T 9867-2008 "Determination of abrasion resistance of vulcanized rubber or thermoplastic rubber (rotary roller abrasion tester method)".

[0148] The antibacterial rates of polyester fibers prepared in Examples 10-12 and Comparative Examples 1-3 against Staphylococcus aureus were tested in accordance with the standard GB / T 20944.3-2008 "Evaluation of antimicrobial properties of textiles - Part 3: Vibration method".

[0149] The polyester fibers prepared in Examples 10-12 and Comparative Examples 1-3 were subjected to heat aging tests in accordance with the standard GB / T 13767-1992 "Determination of Heat Resistance of Textiles". The breaking strength retention rate and volumetric abrasion change rate of the polyester fibers after heat aging were calculated in accordance with the standards GB / T 14337-2008 and GB / T 9867-2008, respectively. The specific data are shown in Table 1.

[0150] Table 1 - Performance Test Data for Each Sample

[0151] Project Group Example 10 Example 11 Example 12 Comparative Example 1 Comparative Example 2 Comparative Example 3 Fracture strength / MPa 7.1 7.6 7.4 4.6 3.5 5.1 <![CDATA[Volume wear amount / mm 3 > 26.7 24.3 25.5 41.2 54.8 48 Antibacterial rate / % 92.6 94.3 93.7 91.5 89.9 43.5 Fracture strength retention rate / % 98.1 98.6 98.3 84.6 76.3 76.2 Volumetric wear change rate / % 102.73 101.5 101.9 129.6 138.2 128.0

[0152] Data Analysis:

[0153] A comparative analysis of the data in Table 1 reveals that the polyester fiber prepared by this invention has a breaking strength of 7.6 MPa and a volumetric abrasion loss of 24.3 mm. 3 While achieving an antibacterial rate of 94.3%, the tensile strength retention rate after thermal aging was 98.6%, and the volumetric wear change rate was 101.5%, all of which were superior to the comparative example. This invention modifies epoxy groups on carboxylated carbon nanotubes through free radical polymerization to obtain modified fillers. The modified fillers, auxiliary additives, and modified PET are then melt-spun together to obtain polyester fiber precursors. The hydroxyl groups in the modified PET form chemical bonds with the epoxy groups in the modified fillers, and a modified antibacterial agent is prepared by co-precipitation. Further, an antibacterial solution is prepared. The polyester fiber precursor is impregnated in the antibacterial solution, and under ultraviolet light irradiation, the olefins in the modified PET segments and the thiol groups in the antibacterial solution undergo a thiol-olefin click reaction to obtain polyester fibers. This not only improves the wear resistance and high temperature resistance of polyester fibers but also enhances their antibacterial properties.

[0154] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementations. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for preparing abrasion-resistant and high-temperature-resistant polyester fiber, characterized in that, Includes the following steps: S1. Place terephthalic acid, ethylene glycol, 1,4-butenediol and catalyst in a reaction vessel under nitrogen atmosphere and stir. Heat to 250-260℃ and keep the reaction at this temperature for 2-3 hours to obtain the prepolymer. S2. Place the prepolymer in a nitrogen-protected reactor and stir. Evacuate the reactor to a vacuum, add trimethyl phosphate, heat to 280-290℃, and keep the temperature for 4-6 hours. Then, perform post-treatment to obtain modified PET. S3. Modified PET, modified filler and auxiliary additives are added to a twin-screw extruder, melt extruded and spun to obtain polyester fiber precursor; S4. The polyester fiber precursor is immersed in an antibacterial solution and then post-treated to obtain polyester fiber. In step S3, the modified filler is prepared by the following steps: A1. Styrene, ethyl acetate, azobisisobutyronitrile and glycidyl methacrylate were placed in a reaction vessel and stirred. The reaction vessel was heated to 65-75℃, maleic anhydride was added, and the reaction was kept at the temperature for 1-2 hours. After post-treatment, intermediate I was obtained. A2. Add carboxylated carbon nanotubes to a ball mill and ball mill them to obtain activated carbon nanotubes; A2. Place activated carbon nanotubes and acetone in a reaction vessel, stir for 20-30 min, add intermediate I, heat to 45-55℃, keep the temperature for 4-6 h, and then process to obtain the modified filler. In step S4, the method for preparing the antibacterial solution includes: B1. Place β-cyclodextrin, deionized water and ethanol in a reaction vessel and stir. Heat the reaction vessel to 55-65℃ and keep it at that temperature for 15-30 min. Slowly add tea polyphenols and react in the dark for 1-2 h. Cool down to 0-5℃ and react in the dark for 10-12 h. Post-treatment yields the modified antibacterial agent. B2. Place the modified antibacterial agent, γ-mercaptopropyltriethoxysilane, ethanol and deionized water in a reaction vessel and stir. Add saturated ammonia water, heat the reaction vessel to 45-55℃, and keep it at this temperature for 1-2 hours. Then, perform post-treatment to obtain the antibacterial solution.

2. The method for preparing a wear-resistant and high-temperature-resistant polyester fiber according to claim 1, characterized in that, In step S1, the weight ratio of terephthalic acid, ethylene glycol, 1,4-butenediol, and catalyst is 6-8:2-4:1-2:0.5-1, and the catalyst is antimony trioxide; in step S2, the weight ratio of prepolymer and trimethyl phosphate is 8-10:0.2-0.4; in step S3, the weight ratio of modified PET, modified filler, and auxiliary additives is 60-80:10-15:5-10, and the auxiliary additives consist of antioxidants, lubricants, antistatic agents, and UV absorbers in a mass ratio of 1:2:1:3; in step S4, the impregnation ratio is 1:30-35.

3. The method for preparing abrasion-resistant and high-temperature-resistant polyester fiber according to claim 1, characterized in that, In step A1, the ratio of styrene, ethyl acetate, azobisisobutyronitrile, glycidyl methacrylate, and maleic anhydride is 4-6g:80-100mL:0.5-1g:2-4g:1-2g; in step A3, the ratio of activated carbon nanotubes, acetone, and intermediate I is 1-2g:50-100mL:5-7g.

4. The method for preparing abrasion-resistant and high-temperature-resistant polyester fiber according to claim 1, characterized in that, The method for preparing the activated carbon nanotubes is as follows: carboxylated carbon nanotubes are added to a planetary ball mill, stainless steel grinding balls of 5-10 mm are added, the ball-to-material ratio is 10:1, the rotation speed is set to 400-500 rpm, the ball milling is performed for 1-2 hours, and the material is passed through a 300-400 mesh sieve to obtain activated carbon nanotubes.

5. The method for preparing abrasion-resistant and high-temperature-resistant polyester fiber according to claim 1, characterized in that, In step B1, the ratio of β-cyclodextrin, deionized water, ethanol, and tea polyphenols is 2-4g:20-30mL:15-20mL:2-4g; in step B2, the ratio of modified antibacterial agent, γ-mercaptopropyltriethoxysilane, ethanol, deionized water, and saturated ammonia is 2-4g:0.5-1g:50-80mL:5-10mL:1-2mL.

6. A wear-resistant and high-temperature-resistant polyester fiber, characterized in that, The wear-resistant and high-temperature resistant polyester fiber is prepared by the method for preparing wear-resistant and high-temperature resistant polyester fiber as described in any one of claims 1-5.

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