Graphene functionalized reinforced modified polyester fiber and method of making the same

Abstract

The application discloses a graphene functionalized reinforced modified polyester fiber and a preparation method thereof. The method comprises the following steps: 1) using dimethyl phthalate, ethylene glycol, a catalyst and a multi-component composite modifier as raw materials to polymerize functionalized modified polyester master batches; and 2) melting and spinning the functionalized modified polyester master batches to obtain graphene functionalized reinforced modified polyester fibers. The self-made multi-component composite modifier is used to prepare the functionalized modified polyester master batches, and then the polyester fibers are prepared, so that the product with excellent mechanical properties, flame-retardant properties, ultraviolet resistance and thermal-oxidative aging resistance can be obtained, the performance requirements of the polyester fibers in larger application scenarios can be better met, and the application prospect of the polyester fibers can be widened.

Description

Technical Field

[0001] This invention relates to the field of polyester fiber materials, and in particular to a graphene-functionalized reinforced modified polyester fiber and its preparation method. Background Technology

[0002] Polyester fiber, commonly known as "polyester," is a synthetic fiber made from organic diacids and diols through chemical polycondensation. It belongs to the category of polymer compounds. Polyester fiber has excellent wrinkle resistance and shape retention, making clothing made from it less prone to wrinkling during wear and able to maintain its original shape. Secondly, polyester fiber has high strength and elastic recovery capabilities, making woven fabrics strong and durable while quickly returning to their original shape. Furthermore, polyester fiber is also abrasion-resistant and lint-free, resulting in a cleaner and neater appearance for fabrics.

[0003] Besides its application in the textile industry, polyester fiber is also finding increasing use in the industrial sector. In the automotive industry, it is used in the manufacture of key components such as interior parts and seat belts. In the construction industry, it is used as a reinforcing material in waterproof membranes and thermal insulation layers. Polyester fiber fabrics are also used as rubber reinforcing materials (such as tire cords and conveyor belts).

[0004] To improve the performance or expand the functions of polyester fibers, reinforcing with inorganic materials is a common method. Graphene, a two-dimensional material composed of a single layer of carbon atoms, possesses excellent thermal, mechanical, electrical, and optical properties. Far-infrared polyester fibers prepared using graphene exhibit excellent far-infrared warmth retention, antistatic, and antibacterial properties, while also enhancing their flame retardancy to a certain extent. For example, patent CN107988650B discloses a method for preparing graphene-reinforced polyester fibers, CN119102002B discloses a graphene-modified multifunctional polyester fiber and its preparation method, as well as its application in down fillings, and CN119082920A discloses a multifunctional polyester fiber based on modified graphene and its preparation method.

[0005] However, the poor compatibility between graphene and polyester systems limits their application to some extent. Furthermore, due to limitations in the amount of graphene added, its improvement on the flame retardant properties of polyester fibers is limited. In addition, UV aging and thermo-oxidative aging are unavoidable problems for polyester. Ultraviolet light causes the polyester fiber molecular chains to break, leading to aging; high-temperature environments cause oxidation reactions, also resulting in fiber aging. Aging of polyester fibers shortens their service life and affects their performance. Patent CN119102002B addresses the poor compatibility issue between graphene and polyester fiber systems to some extent, but it does not improve their aging resistance. Further enhancing the flame retardant ability of polyester fibers could improve their performance and broaden their application areas.

[0006] Therefore, it is now necessary to improve existing technologies to provide more reliable solutions. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a graphene-functionalized reinforced modified polyester fiber and its preparation method, addressing the shortcomings of the prior art.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a method for preparing graphene functionalized reinforced modified polyester fiber, characterized by comprising the following steps:

[0009] 1) Functionalized modified polyester masterbatch was obtained by polymerization using dimethyl terephthalate, ethylene glycol, catalyst and multi-component composite modifier as raw materials;

[0010] 2) Graphene-functionalized reinforced polyester fibers are obtained by melt spinning of functionalized modified polyester masterbatch;

[0011] The multi-component composite modified material is prepared through the following steps:

[0012] S1. Zn-doped carbon dots are grafted onto graphene using a hydrothermal method to obtain a graphene-carbon dot composite.

[0013] S2. Deposit rare earth-doped antimony trioxide nanoparticles on the graphene-carbon dot composite to obtain a graphene-based multi-component composite intermediate.

[0014] S3. Graft tung oil-modified phenolic resin onto a graphene-based multi-component composite intermediate to obtain a multi-component composite modified material.

[0015] Preferably, the multi-component composite modified material is prepared through the following steps:

[0016] S1. Preparation of graphene-carbon dot composite:

[0017] S1-1. Soak graphene in hydrochloric acid, remove it, wash and dry it to obtain pretreated graphene.

[0018] S1-2. Take the pretreated graphene and zinc acetate and add them to an ethanol aqueous solution. Disperse them by ultrasonication. Then add dopamine hydrochloride, lutein, glucose and 3,5-diaminobenzoic acid and disperse them by ultrasonication. Transfer the resulting mixture to a reaction vessel and react it under heating to obtain a graphene-carbon dot composite.

[0019] S2. Preparation of graphene-based multi-component composite intermediates:

[0020] S2-1. Add graphene-carbon dot composite, antimony chloride, lanthanum nitrate, cerium nitrate, and PVP (polyvinylpyrrolidone) to ethanol and disperse by ultrasonication.

[0021] S2-2. Add alkali to the product of step S2-1 under stirring to adjust the pH and obtain a precursor mixture;

[0022] S2-3. The precursor mixture is transferred to a reaction vessel and reacted under heating to obtain a graphene-based multi-component composite intermediate.

[0023] S3. Grafting tung oil-modified phenolic resin onto a graphene-based multi-component composite intermediate:

[0024] S3-1. Mix phenol, tung oil and p-toluenesulfonic acid evenly, heat and stir to react, and obtain the intermediate product;

[0025] S3-2. Take the graphene-based multi-component composite intermediate and add it to formaldehyde. Disperse it by ultrasonication. Add the resulting dispersion mixture to the intermediate product, add sodium hydroxide, and stir under heating to obtain the multi-component composite modified material.

[0026] Preferably, step S1 specifically includes:

[0027] S1-1. Place graphene in hydrochloric acid with a mass concentration of 5-20% and soak it under ultrasound for 1-4 hours. After taking it out, wash it with deionized water until neutral and vacuum dry it at 70-100℃ for 4-16 hours to obtain pretreated graphene.

[0028] S1-2. Take 1-4g of pretreated graphene and 0.1375-0.55g of zinc acetate and add them to 50-200mL of an ethanol-water solution composed of ethanol and deionized water in a volume ratio of 1:1. Disperse the mixture ultrasonically for 15-60min. Then add 0.19-0.76g of dopamine hydrochloride, 0.2845-1.138g of lutein, 0.36-1.44g of glucose, and 0.152-0.608g of 3,5-diaminobenzoic acid. Disperse the mixture ultrasonically for 5-30min. Transfer the resulting mixture to a polytetrafluoroethylene-lined reactor and react at 170-210℃ for 4-16h. Cool to room temperature, centrifuge and filter. Wash the solid product sequentially with deionized water and ethanol, and vacuum dry at 70-100℃ for 6-24h to obtain the graphene-carbon dot composite.

[0029] Preferably, step S2 specifically includes:

[0030] S2-1. Add 0.5-2g of graphene-carbon dot composite, 0.039-0.156g of antimony chloride, 0.029-0.116g of lanthanum nitrate, 0.022-0.086g of cerium nitrate, and 0.15-0.6g of PVP to 75-300mL of ethanol and ultrasonically disperse for 15-60min.

[0031] S2-2. Add a sodium hydroxide solution with a concentration of 0.5-2 mol / L dropwise to the product of step S2-1 under stirring, adjust the pH to 8-9, and obtain a precursor mixture;

[0032] S2-3. The precursor mixture is transferred to a polytetrafluoroethylene-lined reactor and reacted at 185-230℃ for 6-24 hours. After cooling to room temperature, the mixture is filtered, the solid product is washed with ethanol, and dried under vacuum at 60-90℃ to constant weight to obtain a graphene-based multi-component composite intermediate.

[0033] Preferably, step S3 specifically includes:

[0034] S3-1. Take 2.575-10.3g of phenol, 0.75-3g of tung oil, and 0.005-0.02g of p-toluenesulfonic acid and mix them in a reaction vessel. Stir until homogeneous and react at 100-110℃ for 1.5-6h. Cool to room temperature to obtain the intermediate product.

[0035] S3-2. Take 1.25-5g of graphene-based multi-component composite intermediate and add it to 4.3-17.2g of formaldehyde. Disperse the mixture by ultrasonication for 0.5-2h. Add the resulting dispersion mixture to the intermediate product under stirring. After stirring for 15-60min, add 0.025-0.1g of sodium hydroxide. Stir and react at 80-100℃ for 2-8h. Cool to room temperature, wash and filter the product with ethanol, and vacuum dry at 50-80℃ for 6-24h to obtain the multi-component composite modified material.

[0036] Preferably, the multi-component composite modified material is prepared through the following steps:

[0037] S1. Preparation of graphene-carbon dot composite:

[0038] S1-1. Place graphene in 10% hydrochloric acid and immerse it under ultrasound for 2 hours. After removing it, wash it with deionized water until neutral and dry it under vacuum at 90°C for 8 hours to obtain pretreated graphene.

[0039] S1-2. Take 2g of pretreated graphene and 0.275g of zinc acetate and add them to 100mL of an ethanol-water solution composed of ethanol and deionized water in a volume ratio of 1:1. Disperse the mixture by sonication for 30min. Then add 0.38g of dopamine hydrochloride, 0.569g of lutein, 0.72g of glucose, and 0.304g of 3,5-diaminobenzoic acid. Disperse the mixture by sonication for 15min. Transfer the resulting mixture to a reaction vessel lined with polytetrafluoroethylene and react at 190℃ for 8h. Cool to room temperature, centrifuge and filter. Wash the solid product with deionized water and ethanol in sequence. Dry it under vacuum at 80℃ for 12h to obtain the graphene-carbon dot composite.

[0040] S2. Preparation of graphene-based multi-component composite intermediate: S2-1. Add 1g of graphene-carbon dot composite, 0.078g of antimony chloride, 0.058g of lanthanum nitrate, 0.043g of cerium nitrate, and 0.3g of PVP to 150mL of ethanol and ultrasonically disperse for 30min.

[0041] S2-2. Add 1 mol / L sodium hydroxide solution dropwise to the product of step S2-1 under stirring, adjust the pH to 8, and obtain the precursor mixture.

[0042] S2-3. The precursor mixture was transferred to a polytetrafluoroethylene-lined reactor and reacted at 210°C for 12 hours. After cooling to room temperature, the mixture was filtered, the solid product was washed with ethanol, and dried under vacuum at 70°C to constant weight to obtain a graphene-based multi-component composite intermediate.

[0043] S3. Grafting tung oil-modified phenolic resin onto a graphene-based multi-component composite intermediate:

[0044] S3-1. Take 5.15g of phenol, 1.5g of tung oil and 0.01g of p-toluenesulfonic acid and mix them in a reaction vessel. Stir well and react at 105℃ for 3h. Cool to room temperature to obtain the intermediate product.

[0045] S3-2. Take 2.5g of graphene-based multi-component composite intermediate and add it to 8.6g of formaldehyde. Disperse the mixture by ultrasonication for 1h. Add the resulting dispersion mixture to the intermediate product under stirring. After stirring for 30min, add 0.05g of sodium hydroxide. Stir and react at 90℃ for 4h. Cool to room temperature, wash and filter the product with ethanol, and vacuum dry at 60℃ for 12h to obtain the multi-component composite modified material.

[0046] The main synthesis mechanism of the multi-component composite modified material provided by this invention is as follows:

[0047] First, the graphene is acid-washed, and then Zn-doped carbon dots are synthesized in situ on the graphene using a one-pot hydrothermal method. During this process, graphene acid and zinc acetate are mixed, and Zn... 2+ Zn is attached to graphene through electrostatic adsorption, coordination, and other interactions with functional groups such as hydroxyl groups on the graphene surface. Similarly, with the addition of carbon dot materials (dopamine hydrochloride, lutein, glucose, 3,5-diaminobenzoic acid), the carbon dot materials can also bind to Zn through interactions with functional groups such as hydroxyl, amino, and carboxyl groups. 2+ Electrostatic adsorption, coordination and other effects bind to Zn 2+ Finally, carbon dots are generated on the surface through a hydrothermal reaction, allowing the carbon dots to be uniformly and extensively loaded on the graphene to obtain a graphene-carbon dot composite.

[0048] Then, using the graphene-carbon dot composite as a carrier, antimony chloride as the antimony source, PVP (polyvinylpyrrolidone) as the surfactant, and lanthanum and cerium as rare earth doping components, a high-temperature hydrothermal reaction was carried out under alkaline conditions to deposit rare earth lanthanum and cerium oxide-doped nano-antimony trioxide on the graphene-carbon dot composite, thus obtaining a graphene-based multi-component composite intermediate.

[0049] Finally, phenol and tung oil are reacted with p-toluenesulfonic acid as a catalyst to obtain the tung oil-phenol reaction product. Then, formaldehyde and phenol are polymerized in situ under the catalysis of sodium hydroxide, an alkaline catalyst, and tung oil-modified phenolic resin is grafted onto the graphene-based multi-component composite intermediate to obtain the final multi-component composite modified material.

[0050] The multi-component composite modified material prepared in this invention uses graphene as a base carrier, on which Zn-doped carbon dots are uniformly loaded. Then, rare earth lanthanum cerium oxide-doped nano-antimony trioxide particles are deposited on the Zn-doped carbon dots and graphene. Finally, tung oil-modified phenolic resin is grafted onto the graphene to form a multi-component composite multi-effect reinforced structure system. The main reinforcing components in this structure system include: graphene, Zn-doped carbon dots, lanthanum cerium oxide-doped nano-antimony trioxide particles, and tung oil-modified phenolic resin. The mechanism of action of each component is analyzed and explained below to facilitate understanding of this invention.

[0051] 1. In the multi-component composite modified material of the present invention, graphene has excellent mechanical, thermal and electrical properties, and its addition can improve the mechanical strength and flame retardant properties of the fiber.

[0052] 2. The carbon dots in the multi-component composite modified material of the present invention are prepared from dopamine hydrochloride, lutein, glucose and 3,5-diaminobenzoic acid as the main raw materials. They inherit the reducing properties of lutein and 3,5-diaminobenzoic acid and can provide good antioxidant properties for the system. The antioxidant properties can play the following roles: (1) In the synthesis of PET (polyethylene terephthalate), it can help reduce the side reactions caused by thermal degradation or oxidation and reduce product impurities. This role can be combined with the role of Sb2O3 in PET synthesis; (2) In the subsequent application process, the carbon dots with antioxidant properties can capture free radicals with strong oxidizing effect in the system, prevent them from damaging the polymer system, slow down the degradation or oxidation of the polymer, and improve the aging resistance of PET.

[0053] Meanwhile, the carbon dots can efficiently absorb ultraviolet light, giving the system excellent UV protection. On the other hand, the grafting of carbon dots onto graphene can also increase the specific surface area, providing more loading sites for the deposition of lanthanum cerium oxide-doped nano-antimony trioxide particles, and promoting the uniform dispersion of lanthanum cerium oxide-doped nano-antimony trioxide particles.

[0054] The Zn doped in the carbon dots is mainly ZnO nanoparticles, which can play the following roles:

[0055] (1) ZnO itself is a natural ultraviolet absorber, which can further enhance the UV resistance and provide the polymer in the system with durability; ZnO can remove free radicals by absorption or reaction and improve thermal stability, which can complement the antioxidant properties of carbon dots.

[0056] (2) Zinc doping can passivate carbon dot surface defects and reduce non-radiative recombination centers. At the same time, it can suppress carbon dot aggregation through electrostatic repulsion and maintain a high specific surface area (Yang Mingxi. Study on metal ion doped carbon dots prepared based on gluconate and their structure and properties [D]. Jilin University [2025-04-25].); Zn doping can also increase electron cloud density and provide electron transport rate, thereby enhancing the reducibility of carbon dots;

[0057] (3) In the subsequent in-situ grafting of tung oil to modify phenolic resin, during the polymerization of phenolic resin, hydroxymethylphenols form methylene bridges (-CH2-) or ether bonds (-O-) through dehydration condensation. Zinc oxide may accelerate the condensation reaction by activating the hydroxyl groups in hydroxymethyl groups, thereby playing a catalytic role in the polymerization of phenolic resin. Since the nanoparticles of ZnO can be uniformly dispersed in the system of multi-component composite modified materials, this can enhance the above-mentioned role played by ZnO.

[0058] 3. In the multi-component composite modified material of the present invention, one of the roles of Sb2O3 is as a catalyst in the PET synthesis during the preparation stage. In the system of the present invention, since Sb2O3 has a nano-sized structure and is uniformly dispersed, it can contact the reactants more fully, which is beneficial to improving its catalytic efficiency. On the other hand, in the polyester fiber application stage, Sb2O3 plays the role of flame retardant filler. Loading Sb2O3 into the multi-component composite modified material system can achieve its uniform dispersion. This uniform dispersion characteristic can improve the catalytic efficiency in the polyester preparation stage and better exert its flame retardant performance in the subsequent use stage, while reducing its adverse effects on the mechanical properties of the polyester fiber system.

[0059] The lanthanum and cerium rare earth elements doped in it can at least play the following roles:

[0060] (1) For Sb2O3, the doping and composite of rare earth elements can reduce the activation energy of the polycondensation reaction, enabling the reaction to achieve a high-efficiency catalytic effect at a lower temperature. Rare earth elements have abundant outer electron energy levels and variable valence states, which can enhance the redox activity of Sb3⁺ by forming coordinate bonds or electron transfer channels with Sb³⁺ in antimony trioxide, thereby improving the catalytic activity of Sb2O3. Rare earth oxides have high specific surface area and abundant lattice oxygen defects, which can promote the dispersion of antimony trioxide particles and increase the density of active sites in the catalytic system. At the same time, the alkaline sites provided by rare earths help to neutralize the acidic byproducts generated in the reaction and suppress side reactions.

[0061] (2) For carbon dots, the doped rare earth elements are partially attached to the surface of the carbon dots in situ. The rare earth elements are anchored on the surface of the carbon dots in a monodisperse form, forming a highly active metal-carbon interface. The π-conjugated system of rare earth and carbon dots enhances electron delocalization through energy transfer, thereby increasing the electron migration rate and enhancing the reducibility of carbon dots. At the same time, rare earth elements can also stabilize oxygen vacancies in the carbon dot lattice, further enhancing the reducibility of carbon dots.

[0062] (3) For ZnO, doping with rare earth elements can increase the density of hydroxyl groups on the ZnO surface and improve its adsorption capacity for ultraviolet light. At the same time, rare earth oxides themselves also have strong anti-ultraviolet ability (Sun Haiyun. Ultraviolet absorbers and their application in leather chemicals [J]. Leather and Chemical Industry, 2014, 31(5):7.DOI:10.3969 / j.issn.1674-0939.2014.05.003.). Therefore, the combination of rare earth and ZnO can improve the anti-ultraviolet performance of the system.

[0063] (4) Rare earth oxides have high melting points, which can improve high-temperature stability, slow down the degradation rate of materials, and achieve a certain flame retardant and synergistic effect.

[0064] 4. In the multi-component composite modified material of the present invention, the tung oil modified phenolic resin grafted in situ onto the graphene-based multi-component composite intermediate can improve the compatibility of the graphene-based multi-component composite intermediate with the organic system and promote its uniform dispersion in the polyester fiber system, thereby solving the defect of the difficulty in dispersing inorganic components such as graphene, Zn-doped carbon dots, and lanthanum cerium oxide-doped nano-antimony trioxide particles in the polyester organic system.

[0065] The uniform loading of Zn-doped carbon dots and lanthanum-cerium oxide-doped antimony trioxide nanoparticles on graphene can mechanically pull the two-dimensional graphene structure, promote the spread of graphene, reduce its curling and entanglement, and thus enhance its performance.

[0066] Meanwhile, the phenolic resin molecule contains benzene rings and phenolic hydroxyl groups, which gives it high thermal stability and oxygen index. Phenolic resin decomposes at high temperatures to produce acidic substances, which further decompose to produce non-flammable gases such as carbon dioxide and water vapor, giving it certain flame retardant properties. Therefore, the addition of tung oil-modified phenolic resin can improve the heat resistance and flame retardant properties of polyester.

[0067] Furthermore, modification with tung oil can improve toughness, adhesion, and flame retardancy. When the prepared PET fibers are used as rubber reinforcement materials (e.g., tire cords, conveyor belts, etc.), the addition of tung oil-modified phenolic resin to the PET system can improve the bonding performance between the prepared polyester fibers and the rubber interface (Lu Qinwei. Synthesis of phenolic resin and its influence on the interfacial properties of PET reinforced composite materials [D]. Anhui University of Technology, 2016.), which is beneficial to improving the application effect of polyester fibers in different application scenarios.

[0068] The main principle behind tung oil's ability to improve flame retardancy is as follows: α-tung acid and other unsaturated fatty acids in tung oil form a dense carbon layer through pyrolysis, which effectively isolates oxygen from contact with the substrate and slows down heat transfer; epoxidation and ring-opening reactions cause the tung oil molecular chains to form a cross-linked structure, improving the thermal stability of the material and delaying the thermal decomposition process.

[0069] Analysis of the mechanism of action of each major component in the multi-component composite modified material of the present invention shows that the present invention constructs a composite system with a special structure by means of graphene, Zn-doped carbon dots, lanthanum cerium oxide-doped nano-antimony trioxide particles and tung oil-modified phenolic resin. While giving full play to the reinforcing effect of each component, it can also play a synergistic role in improving the flame retardant performance, antioxidant performance and UV resistance of the prepared polyester fiber by means of the mutual cooperation and complementary reinforcement between the components.

[0070] Preferably, the preparation method of the graphene-functionalized reinforced modified polyester fiber includes the following steps:

[0071] 1) Dimethyl terephthalate, ethylene glycol, and catalyst are mixed and heated to carry out transesterification reaction. Then, multi-component composite modifier is added, stirred evenly, and heated to carry out polycondensation reaction. After the reaction is completed, the material is discharged, cooled, and pelletized to obtain functionalized modified polyester masterbatch.

[0072] 2) The functionalized modified polyester masterbatch is dried, and then melt-spun, wound, and stretched in a melt spinning machine to obtain graphene functionalized reinforced modified polyester fiber.

[0073] Preferably, the catalyst is one or both of zinc acetate and manganese acetate.

[0074] Preferably, the preparation method of the graphene-functionalized reinforced modified polyester fiber includes the following steps:

[0075] 1) Take 50-200g of dimethyl terephthalate, 34-136g of ethylene glycol, and 0.09-0.36g of zinc acetate and add them to the reaction vessel. Perform transesterification reaction at 200-250℃ for 1-4 hours. Then add 0.25-9.0g of multi-component composite modifier, stir evenly, heat to 255-290℃, and polycondense for 1-4 hours. After the reaction is completed, pressurize with nitrogen to discharge the material, cool it, and granulate it to obtain functionalized modified polyester masterbatch.

[0076] 2) The functionalized modified polyester masterbatch is dried at 80-110℃ for 2-8 hours, and then melt-spun, wound and stretched in a melt spinning machine to obtain graphene functionalized reinforced modified polyester fiber; wherein the spinning temperature is 270-300℃, the winding rate is 600-2400m / min, the stretching ratio is 1-3 times, and the stretching rate is 350-1400m / min.

[0077] The present invention also provides a graphene-functionalized reinforced modified polyester fiber, which is prepared by the method described above.

[0078] The beneficial effects of this invention are:

[0079] This invention provides a graphene-functionalized reinforced and modified polyester fiber and its preparation method. This invention uses a self-made multi-component composite modified material to prepare a functionalized modified polyester masterbatch, and then prepares polyester fiber. This can obtain a product with excellent mechanical properties, flame retardant properties, UV resistance and thermo-oxidative aging resistance, which can better meet the performance requirements of polyester fiber in a wider range of application scenarios and broaden the application prospects of polyester fiber.

[0080] This invention uses graphene as a base carrier, uniformly loading Zn-doped carbon dots onto it. Then, rare earth lanthanum cerium oxide-doped nano-antimony trioxide particles are deposited on the Zn-doped carbon dots and graphene. Finally, tung oil-modified phenolic resin is grafted onto the graphene, resulting in a multi-component composite multi-effect reinforcing system with a special structure. The multi-component components—graphene, Zn-doped carbon dots, lanthanum cerium oxide-doped nano-antimony trioxide particles, and tung oil-modified phenolic resin—fully utilize their individual reinforcing effects while also complementing and reinforcing each other. This results in a synergistic enhancement effect on the flame retardant, antioxidant, and UV-resistant properties of the prepared polyester fibers, thereby significantly improving the overall performance of the prepared polyester fibers. Attached Figure Description

[0081] Figure 1 The infrared absorption spectrum of the graphene-based multi-component composite intermediate prepared in Example 1;

[0082] Figure 2 The ultraviolet-visible absorption spectra of the multi-component composite modified materials prepared in Example 1, Comparative Example 3, and Comparative Example 4 are shown.

[0083] Figure 3 The antioxidant performance test results are for the multi-component composite modified materials prepared in Example 1, Comparative Example 2, Comparative Example 3, and Comparative Example 4.

[0084] Figure 4 The intrinsic viscosity test results are for the functionalized modified polyester masterbatches prepared in the examples and comparative examples;

[0085] Figure 5 The end carboxyl group values ​​of the functionalized modified polyester masterbatches prepared in the examples and comparative examples are shown in the test results.

[0086] Figure 6 The tensile strength test results are for the polyester fibers prepared in the examples and comparative examples;

[0087] Figure 7 The limiting oxygen index test results are for the polyester fibers prepared in the examples and comparative examples;

[0088] Figure 8 The UV resistance test results are for the polyester fibers prepared in the examples and comparative examples;

[0089] Figure 9 The results of the thermo-oxidative aging performance tests of the polyester fibers prepared in the examples and comparative examples are shown. Detailed Implementation

[0090] The present invention will be further described in detail below with reference to embodiments, so that those skilled in the art can implement it based on the description.

[0091] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0092] Unless otherwise specified, the experimental methods used in the following examples are conventional methods. Unless otherwise specified, the materials and reagents used in the following examples are commercially available. For examples where specific conditions are not specified, conventional conditions or conditions recommended by the manufacturer are followed. For reagents or instruments whose manufacturers are not specified, they are all commercially available products.

[0093] The sources of some of the raw materials involved in the following examples and comparative examples are as follows:

[0094] Dimethyl terephthalate, brand: SK Korea, purchased from Shanghai Fengrui Chemical Co., Ltd.;

[0095] Graphene, with an average particle size of 20 μm, was purchased from Shanghai Fengguang Plastic Technology Co., Ltd.

[0096] Antimony trioxide, with an average particle size of 200 nm, was purchased from Shanghai Naio Nanotechnology Co., Ltd.

[0097] Tung oil, industrial grade (content > 99%), purchased from Shandong Jibei New Materials Co., Ltd.

[0098] Phenol, Shanghai Hengxinde Chemical Co., Ltd.

[0099] Example 1

[0100] A method for preparing graphene-functionalized reinforced polyester fiber includes the following steps:

[0101] 1) Take 100g of dimethyl terephthalate, 68g of ethylene glycol and 0.18g of zinc acetate and add them to the reactor. Perform transesterification reaction at 225℃ for 2 hours. Then add 4.5g of multi-component composite modifier, stir evenly, heat to 270℃ and polycondense for 2 hours. After the reaction is completed, pressurize with nitrogen to discharge the material, cool it, and granulate it to obtain functionalized modified polyester masterbatch.

[0102] 2) The functionalized modified polyester masterbatch was dried at 100℃ for 4 hours, and then melt-spun, wound and stretched in a melt spinning machine to obtain graphene functionalized reinforced modified polyester fiber; wherein the spinning temperature was 290℃, the winding rate was 1200m / min, the stretching ratio was 2 times and the stretching rate was 700m / min.

[0103] The multi-component composite modified material is prepared through the following steps:

[0104] S1. Preparation of graphene-carbon dot composite:

[0105] S1-1. Place graphene in 10% hydrochloric acid and immerse it under ultrasound for 2 hours. After removing it, wash it with deionized water until neutral and dry it under vacuum at 90°C for 8 hours to obtain pretreated graphene.

[0106] S1-2. Take 2g of pretreated graphene and 0.275g of zinc acetate and add them to 100mL of an ethanol-water solution composed of ethanol and deionized water in a volume ratio of 1:1. Disperse the mixture by sonication for 30min. Then add 0.38g of dopamine hydrochloride, 0.569g of lutein, 0.72g of glucose, and 0.304g of 3,5-diaminobenzoic acid. Disperse the mixture by sonication for 15min. Transfer the resulting mixture to a reaction vessel lined with polytetrafluoroethylene and react at 190℃ for 8h. Cool to room temperature, centrifuge and filter. Wash the solid product with deionized water and ethanol in sequence. Dry it under vacuum at 80℃ for 12h to obtain the graphene-carbon dot composite.

[0107] S2. Preparation of graphene-based multi-component composite intermediates:

[0108] S2-1. Add 1g of graphene-carbon dot composite, 0.078g of antimony chloride, 0.058g of lanthanum nitrate, 0.043g of cerium nitrate, and 0.3g of PVP to 150mL of ethanol and sonicate for 30min.

[0109] S2-2. Add 1 mol / L sodium hydroxide solution dropwise to the product of step S2-1 under stirring, adjust the pH to 8, and obtain the precursor mixture.

[0110] S2-3. The precursor mixture was transferred to a polytetrafluoroethylene-lined reactor and reacted at 210°C for 12 hours. After cooling to room temperature, the mixture was filtered, the solid product was washed with ethanol, and dried under vacuum at 70°C to constant weight to obtain a graphene-based multi-component composite intermediate.

[0111] S3. Grafting tung oil-modified phenolic resin onto a graphene-based multi-component composite intermediate:

[0112] S3-1. Take 5.15g of phenol, 1.5g of tung oil and 0.01g of p-toluenesulfonic acid and mix them in a reaction vessel. Stir well and react at 105℃ for 3h. Cool to room temperature to obtain the intermediate product.

[0113] S3-2. Take 2.5g of graphene-based multi-component composite intermediate and add it to 8.6g of formaldehyde. Disperse the mixture by ultrasonication for 1h. Add the resulting dispersion mixture to the intermediate product under stirring. After stirring for 30min, add 0.05g of sodium hydroxide. Stir and react at 90℃ for 4h. Cool to room temperature, wash and filter the product with ethanol, and vacuum dry at 60℃ for 12h to obtain the multi-component composite modified material.

[0114] Example 2

[0115] A method for preparing graphene-functionalized reinforced polyester fiber includes the following steps:

[0116] 1) Take 100g of dimethyl terephthalate, 68g of ethylene glycol and 0.18g of zinc acetate and add them to the reaction vessel. Perform transesterification reaction at 225℃ for 2 hours. Then add 4.0g of multi-component composite modifier, stir evenly, heat to 275℃ and polycondense for 2 hours. After the reaction is completed, pressurize with nitrogen to discharge the material, cool it, and granulate it to obtain functionalized modified polyester masterbatch.

[0117] 2) The functionalized modified polyester masterbatch was dried at 100℃ for 4 hours, and then melt-spun, wound and stretched in a melt spinning machine to obtain graphene functionalized reinforced modified polyester fiber; wherein the spinning temperature was 290℃, the winding rate was 1200m / min, the stretching ratio was 2 times and the stretching rate was 700m / min.

[0118] The multi-component composite modified material is prepared through the following steps:

[0119] S1. Preparation of graphene-carbon dot composite:

[0120] S1-1. Place graphene in 10% hydrochloric acid and immerse it under ultrasound for 2 hours. After removing it, wash it with deionized water until neutral and dry it under vacuum at 90°C for 8 hours to obtain pretreated graphene.

[0121] S1-2. Take 2g of pretreated graphene and 0.25g of zinc acetate and add them to 100mL of an ethanol-water solution composed of ethanol and deionized water in a volume ratio of 1:1. Disperse the mixture by sonication for 30min. Then add 0.38g of dopamine hydrochloride, 0.569g of lutein, 0.72g of glucose, and 0.304g of 3,5-diaminobenzoic acid. Disperse the mixture by sonication for 15min. Transfer the resulting mixture to a reaction vessel lined with polytetrafluoroethylene and react at 190℃ for 8h. Cool to room temperature, centrifuge and filter. Wash the solid product with deionized water and ethanol in sequence. Dry it under vacuum at 80℃ for 12h to obtain the graphene-carbon dot composite.

[0122] S2. Preparation of graphene-based multi-component composite intermediates:

[0123] S2-1. Add 1.2g graphene-carbon dot composite, 0.078g antimony chloride, 0.058g lanthanum nitrate, 0.043g cerium nitrate, and 0.3g PVP to 150mL of ethanol and sonicate for 30min.

[0124] S2-2. Add 1 mol / L sodium hydroxide solution dropwise to the product of step S2-1 under stirring, adjust the pH to 8, and obtain the precursor mixture;

[0125] S2-3. The precursor mixture was transferred to a polytetrafluoroethylene-lined reactor and reacted at 210°C for 12 hours. After cooling to room temperature, the mixture was filtered, the solid product was washed with ethanol, and dried under vacuum at 70°C to constant weight to obtain a graphene-based multi-component composite intermediate.

[0126] S3. Grafting tung oil-modified phenolic resin onto a graphene-based multi-component composite intermediate:

[0127] S3-1. Take 5.15g of phenol, 1.5g of tung oil and 0.01g of p-toluenesulfonic acid and mix them in a reaction vessel. Stir well and react at 105℃ for 3h. Cool to room temperature to obtain the intermediate product.

[0128] S3-2. Take 2.5g of graphene-based multi-component composite intermediate and add it to 8.6g of formaldehyde. Disperse the mixture by ultrasonication for 1h. Add the resulting dispersion mixture to the intermediate product under stirring. After stirring for 30min, add 0.05g of sodium hydroxide. Stir and react at 90℃ for 4h. Cool to room temperature, wash and filter the product with ethanol, and vacuum dry at 60℃ for 12h to obtain the multi-component composite modified material.

[0129] Example 3

[0130] A method for preparing graphene-functionalized reinforced polyester fiber includes the following steps:

[0131] 1) Take 100g of dimethyl terephthalate, 68g of ethylene glycol and 0.16g of zinc acetate and add them to the reactor. Perform transesterification reaction at 210℃ for 2.5h. Then add 4.5g of multi-component composite modifier, stir evenly, heat to 275℃ and polycondense for 2h. After the reaction is completed, pressurize with nitrogen to discharge the material, cool it, and granulate it to obtain functionalized modified polyester masterbatch.

[0132] 2) The functionalized modified polyester masterbatch was dried at 100℃ for 4 hours, and then melt-spun, wound and stretched in a melt spinning machine to obtain graphene functionalized reinforced modified polyester fiber; wherein the spinning temperature was 290℃, the winding rate was 1000m / min, the stretching ratio was 2 times and the stretching rate was 800m / min.

[0133] The preparation method of the multi-component composite modified material is the same as that in Example 1.

[0134] Comparative Example 1

[0135] A method for preparing modified polyester fiber includes the following steps:

[0136] 1) Take 100g of dimethyl terephthalate, 68g of ethylene glycol and 0.18g of zinc acetate and add them to the reaction vessel. The transesterification reaction is carried out at 225℃ for 2h. Then add 0.2g of antimony trioxide and 2g of graphene, stir evenly, heat to 270℃ and polycondense for 2h. After the reaction is completed, pressurize with nitrogen to discharge the material, cool it, and granulate it to obtain functionalized modified polyester masterbatch.

[0137] 2) The functionalized modified polyester masterbatch was dried at 100℃ for 4 hours, and then melt-spun, wound and stretched in a melt spinning machine to obtain graphene functionalized reinforced modified polyester fiber; wherein the spinning temperature was 290℃, the winding rate was 1200m / min, the stretching ratio was 2 times and the stretching rate was 700m / min.

[0138] Comparative Example 2

[0139] The only difference between this example and Example 1 is that:

[0140] The multi-component composite modified material in this example was prepared through the following steps:

[0141] S1. Place the graphene in 10% hydrochloric acid and immerse it under ultrasound for 2 hours. After removing it, wash it with deionized water until neutral and dry it under vacuum at 90°C for 8 hours to obtain pretreated graphene.

[0142] S2. Preparation of graphene-based multi-component composite intermediates:

[0143] S2-1. Add 1g of pretreated graphene, 0.078g of antimony chloride, 0.058g of lanthanum nitrate, 0.043g of cerium nitrate, and 0.3g of PVP to 150mL of ethanol and ultrasonically disperse for 30min.

[0144] S2-2. Add 1 mol / L sodium hydroxide solution dropwise to the product of step S2-1 under stirring, adjust the pH to 8, and obtain the precursor mixture.

[0145] S2-3. The precursor mixture was transferred to a polytetrafluoroethylene-lined reactor and reacted at 210°C for 12 hours. After cooling to room temperature, the mixture was filtered, the solid product was washed with ethanol, and dried under vacuum at 70°C to constant weight to obtain a graphene-based multi-component composite intermediate.

[0146] S3. Graft tung oil-modified phenolic resin onto the graphene-based multi-component composite intermediate, following the same steps as in Example 1.

[0147] Comparative Example 3

[0148] The only difference between this example and Example 1 is that:

[0149] The multi-component composite modified material in this example was prepared through the following steps:

[0150] S1. Preparation of graphene-carbon dot composite:

[0151] S1-1. Place graphene in 10% hydrochloric acid and immerse it under ultrasound for 2 hours. After removing it, wash it with deionized water until neutral and dry it under vacuum at 90°C for 8 hours to obtain pretreated graphene.

[0152] S1-2. Take 2g of pretreated graphene and add it to 100mL of an ethanol-water solution composed of ethanol and deionized water in a volume ratio of 1:1. Disperse the solution by sonication for 30min. Then add 0.38g of dopamine hydrochloride, 0.569g of lutein, 0.72g of glucose, and 0.304g of 3,5-diaminobenzoic acid. Disperse the solution by sonication for 15min. Transfer the resulting mixture to a reaction vessel lined with polytetrafluoroethylene and react at 190℃ for 8h. Cool to room temperature, centrifuge and filter. Wash the solid product with deionized water and ethanol in sequence. Dry it under vacuum at 80℃ for 12h to obtain the graphene-carbon dot composite.

[0153] S2. Preparation of graphene-based multi-component composite intermediates, the steps are the same as in Example 1;

[0154] S3. Graft tung oil-modified phenolic resin onto the graphene-based multi-component composite intermediate, following the same steps as in Example 1.

[0155] Comparative Example 4

[0156] The only difference between this example and Example 1 is that:

[0157] The multi-component composite modified material in this example was prepared through the following steps:

[0158] S1. Prepare graphene-carbon dot composite, following the same steps as in Example 1;

[0159] S2. Preparation of graphene-based multi-component composite intermediates:

[0160] S2-1. Add 1g of graphene-carbon dot composite, 0.078g of antimony chloride, and 0.3g of PVP to 150mL of ethanol and sonicate for 30min.

[0161] S2-2. Add 1 mol / L sodium hydroxide solution dropwise to the product of step S2-1 under stirring, adjust the pH to 8, and obtain the precursor mixture.

[0162] S2-3. The precursor mixture was transferred to a polytetrafluoroethylene-lined reactor and reacted at 210°C for 12 hours. After cooling to room temperature, the mixture was filtered, the solid product was washed with ethanol, and dried under vacuum at 70°C to constant weight to obtain a graphene-based multi-component composite intermediate.

[0163] S3. Graft tung oil-modified phenolic resin onto the graphene-based multi-component composite intermediate, following the same steps as in Example 1.

[0164] Comparative Example 5

[0165] The only difference between this example and Example 1 is that this example uses the graphene-based multi-component composite intermediate prepared in Example 1 as the multi-component composite modification material.

[0166] Comparative Example 6

[0167] The multi-component composite modified material in this example was prepared through the following steps:

[0168] S1. Prepare graphene-carbon dot composite, following the same steps as in Example 1;

[0169] S2. Preparation of graphene-based multi-component composite intermediates, the steps are the same as in Example 1;

[0170] S3. Grafting phenolic resin onto a graphene-based multi-component composite intermediate:

[0171] 2.5g of graphene-based multi-component composite intermediate was added to 8.6g of formaldehyde and ultrasonically dispersed for 1h. The resulting dispersion mixture was added to 5.15g of phenol under stirring. After stirring for 30min, 0.05g of sodium hydroxide was added. The mixture was stirred at 90℃ for 4h and cooled to room temperature. The product was washed with ethanol, filtered, and vacuum dried at 60℃ for 12h to obtain the multi-component composite modified material.

[0172] I. Performance Characterization

[0173] 1. Reference Figure 1 The image shows the infrared absorption spectrum of the graphene-based multi-component composite intermediate prepared in Example 1, at 1585 cm⁻¹. 1 1040cm- 1 The characteristic peaks in the vicinity originate from the sp2 and sp3 hybridized C-C bonds in graphene; the characteristic peaks of amino, carboxyl, hydroxyl, and benzene rings originate from the functional groups on the carbon dots, indicating the successful synthesis of the carbon dots; the appearance of the Zn-O characteristic peak indicates the successful doping of Zn, and the appearance of the characteristic peaks of Sb-O, Ce-O, and La-O indicates the successful deposition of rare earth lanthanum cerium oxide-doped nano-antimony trioxide; in summary, this indicates the successful preparation of a graphene-based multi-component composite intermediate.

[0174] 2. Ultraviolet absorption spectrum

[0175] Reference Figure 2 The figures show the UV-Vis absorption spectra of the multi-component composite modified materials prepared in Examples 1, 3, and 4. It can be seen that the UV absorption capacity of Example 1 is stronger than that of Comparative Examples 3 and 4.

[0176] 3. Antioxidant properties

[0177] The antioxidant properties of the multi-component composite modified materials prepared in Example 1, Comparative Example 2, Comparative Example 3, and Comparative Example 4 were tested using the following methods:

[0178] The prepared multi-component composite modified material was added to ethanol and ultrasonically dispersed to prepare a dispersion with a concentration of 1 mg / mL. The antioxidant performance of the dispersion over a certain period of time was tested using a DPPH free radical scavenging ability test kit (catalog number LE-1-168, Hefei Lier Biotechnology Co., Ltd.).

[0179] Measurement principle: DPPH free radicals have unpaired electrons, and their alcoholic solution is purple. They have strong absorption at 515 nm. When antioxidants are present, DPPH free radicals are scavenged, the solution color becomes lighter, and the absorbance at 515 nm decreases. Within a certain range, the change in absorbance is directly proportional to the degree of free radical scavenging. Specifically, the lower the absorbance at 515 nm, the stronger the antioxidant performance.

[0180] Test results are as follows Figure 3 As shown in the test results, the antioxidant properties of the multi-component composite modified material in Example 1 are stronger than those of Comparative Examples 2, 3, and 4, and Comparative Example 2 has virtually no antioxidant properties, indicating that the antioxidant properties mainly come from carbon dots.

[0181] II. Performance Testing

[0182] 1. Intrinsic viscosity and terminal carboxyl group value of functionalized modified polyester masterbatch

[0183] The intrinsic viscosity and terminal carboxyl group value of the functionalized modified polyester masterbatches prepared in the examples and comparative examples were tested according to the standard GB / T 14190-2008 "Test Methods for Fiber Grade Polyester Chips (PET)". The test results are shown in Table 1 below. Figures 4-5 As shown:

[0184] Table 1

[0185] Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 intrinsic viscosity dL / g 1.19 1.15 1.18 0.64 0.95 0.87 0.82 0.69 1.06 Terminal carboxyl group value (mol / t) 21.04 20.35 20.95 11.32 18.27 15.38 14.50 13.02 19.22

[0186] The test results show that the intrinsic viscosity and terminal carboxyl group value of the functionalized modified polyester masterbatches prepared in Comparative Examples 1-6 decreased to varying degrees compared with those in the Examples.

[0187] 2. Properties of polyester fibers

[0188] (1) Mechanical properties

[0189] The breaking strength of the polyester fibers prepared in the examples and comparative examples was measured in accordance with the standard GB / T 14344-2022 Test Method for Tensile Properties of Chemical Fiber Filaments.

[0190] (2) Flame retardant properties

[0191] The limiting oxygen index (LOI) of the polyester fibers prepared in the examples and comparative examples was determined using an oxygen index tester.

[0192] (3) UV protection

[0193] The UV resistance of the polyester fibers prepared in the examples and comparative examples was measured: UV irradiation was performed with the UV lamp 20 cm away from the sample, the power was 30 W, and the UV irradiation treatment lasted for 48 h; then the breaking strength after UV irradiation treatment was measured according to the standard "GB / T 14344-2022 Test Method for Tensile Properties of Chemical Fiber Filaments", and the breaking strength retention rate was calculated.

[0194] (4) Thermo-oxidative aging performance

[0195] The thermo-oxidative aging properties of the polyester fibers prepared in the examples and comparative examples were measured: The samples were placed at 150°C in an air atmosphere for 120 hours for thermo-oxidative aging treatment. Then, the breaking strength after thermo-oxidative aging treatment was measured in accordance with the standard GB / T 14344-2022 Test Method for Tensile Properties of Chemical Fiber Filaments, and the breaking strength retention rate was calculated.

[0196] The test results are shown in Table 2 below. Figures 6-9 As shown:

[0197] Table 2

[0198] Fracture strength (cN / detx) LOI (%) Fracture strength retention rate after ultraviolet irradiation (%) Fracture strength retention rate after thermo-oxidative aging (%) Example 1 4.9 35.3 96.2 95.5 Example 2 4.6 34.2 95.4 94.9 Example 3 4.8 35 96.1 95.2 Comparative Example 1 2.7 23.4 62.7 64.1 Comparative Example 2 4.1 31.5 81.4 80.2 Comparative Example 3 3.5 33.7 85.6 87.0 Comparative Example 4 3.4 29 84.2 85.5 Comparative Example 5 2.9 26.3 89.5 89.9 Comparative Example 6 4.5 30.8 94.4 92.3

[0199] The test results show that the polyester fibers prepared in Examples 1-3 have excellent mechanical and flame retardant properties, as well as good UV resistance and thermo-oxidative aging resistance. However, the overall performance of the polyester fibers prepared in each comparative example showed a decline to varying degrees.

[0200] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details.

Claims

1. A method for preparing graphene-functionalized reinforced modified polyester fiber, characterized in that, Includes the following steps: 1) Functionalized modified polyester masterbatch was obtained by polymerization using dimethyl terephthalate, ethylene glycol, catalyst and multi-component composite modifier as raw materials; 2) Graphene-functionalized reinforced polyester fibers are obtained by melt spinning of functionalized modified polyester masterbatch; The multi-component composite modified material is prepared through the following steps: S1. Preparation of graphene-carbon dot composite: S1-1. Soak graphene in hydrochloric acid, remove it, wash and dry it to obtain pretreated graphene. S1-2. Take the pretreated graphene and zinc acetate and add them to an ethanol aqueous solution. Disperse them by ultrasonication. Then add dopamine hydrochloride, lutein, glucose and 3,5-diaminobenzoic acid and disperse them by ultrasonication. Transfer the resulting mixture to a reaction vessel and react it under heating to obtain a graphene-carbon dot composite. S2. Preparation of graphene-based multi-component composite intermediates: S2-1. Add graphene-carbon dot composite, antimony chloride, lanthanum nitrate, cerium nitrate, and PVP to ethanol and disperse by ultrasonication. S2-2. Add alkali to the product of step S2-1 under stirring to adjust the pH and obtain a precursor mixture; S2-3. The precursor mixture is transferred to a reaction vessel and reacted under heating to obtain a graphene-based multi-component composite intermediate. S3. Grafting tung oil-modified phenolic resin onto a graphene-based multi-component composite intermediate: S3-1. Mix phenol, tung oil and p-toluenesulfonic acid evenly, heat and stir to react, and obtain the intermediate product; S3-2. Take the graphene-based multi-component composite intermediate and add it to formaldehyde. Disperse it by ultrasonication. Add the resulting dispersion mixture to the intermediate product, add sodium hydroxide, and stir under heating to obtain the multi-component composite modified material.

2. The method for preparing graphene-functionalized reinforced modified polyester fiber according to claim 1, characterized in that, Step S1 is as follows: S1-1. Place graphene in hydrochloric acid with a mass concentration of 5-20% and soak it under ultrasound for 1-4 hours. After taking it out, wash it with deionized water until neutral and vacuum dry it at 70-100℃ for 4-16 hours to obtain pretreated graphene. S1-2. Take 1-4g of pretreated graphene and 0.1375-0.55g of zinc acetate and add them to 50-200mL of an ethanol-water solution composed of ethanol and deionized water in a volume ratio of 1:

1. Disperse the mixture ultrasonically for 15-60min. Then add 0.19-0.76g of dopamine hydrochloride, 0.2845-1.138g of lutein, 0.36-1.44g of glucose, and 0.152-0.608g of 3,5-diaminobenzoic acid. Disperse the mixture ultrasonically for 5-30min. Transfer the resulting mixture to a polytetrafluoroethylene-lined reactor and react at 170-210℃ for 4-16h. Cool to room temperature, centrifuge and filter. Wash the solid product sequentially with deionized water and ethanol, and vacuum dry at 70-100℃ for 6-24h to obtain the graphene-carbon dot composite.

3. The method for preparing graphene-functionalized reinforced modified polyester fiber according to claim 1, characterized in that, Step S2 is as follows: S2-1. Add 0.5-2g of graphene-carbon dot composite, 0.039-0.156g of antimony chloride, 0.029-0.116g of lanthanum nitrate, 0.022-0.086g of cerium nitrate, and 0.15-0.6g of PVP to 75-300mL of ethanol and ultrasonically disperse for 15-60min. S2-2. Add a sodium hydroxide solution with a concentration of 0.5-2 mol / L dropwise to the product of step S2-1 under stirring, adjust the pH to 8-9, and obtain a precursor mixture; S2-3. The precursor mixture is transferred to a polytetrafluoroethylene-lined reactor and reacted at 185-230℃ for 6-24 hours. After cooling to room temperature, the mixture is filtered, the solid product is washed with ethanol, and dried under vacuum at 60-90℃ to constant weight to obtain a graphene-based multi-component composite intermediate.

4. The method for preparing graphene-functionalized reinforced modified polyester fiber according to claim 1, characterized in that, Step S3 is as follows: S3-1. Take 2.575-10.3g of phenol, 0.75-3g of tung oil, and 0.005-0.02g of p-toluenesulfonic acid and mix them in a reaction vessel. Stir until homogeneous and react at 100-110℃ for 1.5-6h. Cool to room temperature to obtain the intermediate product. S3-2. Take 1.25-5g of graphene-based multi-component composite intermediate and add it to 4.3-17.2g of formaldehyde. Disperse the mixture by ultrasonication for 0.5-2h. Add the resulting dispersion mixture to the intermediate product under stirring. After stirring for 15-60min, add 0.025-0.1g of sodium hydroxide. Stir and react at 80-100℃ for 2-8h. Cool to room temperature, wash and filter the product with ethanol, and vacuum dry at 50-80℃ for 6-24h to obtain the multi-component composite modified material.

5. The method for preparing graphene-functionalized reinforced modified polyester fiber according to claim 1, characterized in that, The multi-component composite modified material is prepared through the following steps: S1. Preparation of graphene-carbon dot composite: S1-1. Place graphene in 10% hydrochloric acid and immerse it under ultrasound for 2 hours. After removing it, wash it with deionized water until neutral and dry it under vacuum at 90°C for 8 hours to obtain pretreated graphene. S1-2. Take 2g of pretreated graphene and 0.275g of zinc acetate and add them to 100mL of an ethanol-water solution composed of ethanol and deionized water in a volume ratio of 1:

1. Disperse the mixture by sonication for 30min. Then add 0.38g of dopamine hydrochloride, 0.569g of lutein, 0.72g of glucose, and 0.304g of 3,5-diaminobenzoic acid. Disperse the mixture by sonication for 15min. Transfer the resulting mixture to a reaction vessel lined with polytetrafluoroethylene and react at 190℃ for 8h. Cool to room temperature, centrifuge and filter. Wash the solid product with deionized water and ethanol in sequence. Dry it under vacuum at 80℃ for 12h to obtain the graphene-carbon dot composite. S2. Preparation of graphene-based multi-component composite intermediate: S2-1. Add 1g of graphene-carbon dot composite, 0.078g of antimony chloride, 0.058g of lanthanum nitrate, 0.043g of cerium nitrate, and 0.3g of PVP to 150mL of ethanol and ultrasonically disperse for 30min. S2-2. Add 1 mol / L sodium hydroxide solution dropwise to the product of step S2-1 under stirring, adjust the pH to 8, and obtain the precursor mixture; S2-3. The precursor mixture was transferred to a polytetrafluoroethylene-lined reactor and reacted at 210°C for 12 hours. After cooling to room temperature, the mixture was filtered, the solid product was washed with ethanol, and dried under vacuum at 70°C to constant weight to obtain a graphene-based multi-component composite intermediate. S3. Grafting tung oil-modified phenolic resin onto a graphene-based multi-component composite intermediate: S3-1. Take 5.15g of phenol, 1.5g of tung oil and 0.01g of p-toluenesulfonic acid and mix them in a reaction vessel. Stir well and react at 105℃ for 3h. Cool to room temperature to obtain the intermediate product. S3-2. Take 2.5g of graphene-based multi-component composite intermediate and add it to 8.6g of formaldehyde. Disperse the mixture by ultrasonication for 1h. Add the resulting dispersion mixture to the intermediate product under stirring. After stirring for 30min, add 0.05g of sodium hydroxide. Stir and react at 90℃ for 4h. Cool to room temperature, wash and filter the product with ethanol, and vacuum dry at 60℃ for 12h to obtain the multi-component composite modified material.

6. The method for preparing graphene-functionalized reinforced modified polyester fiber according to claim 1, characterized in that, Includes the following steps: 1) Dimethyl terephthalate, ethylene glycol, and catalyst are mixed and heated to carry out transesterification reaction. Then, multi-component composite modifier is added, stirred evenly, and heated to carry out polycondensation reaction. After the reaction is completed, the material is discharged, cooled, and pelletized to obtain functionalized modified polyester masterbatch. 2) The functionalized modified polyester masterbatch is dried, and then melt-spun, wound, and stretched in a melt spinning machine to obtain graphene functionalized reinforced modified polyester fiber.

7. The method for preparing graphene-functionalized reinforced modified polyester fiber according to claim 6, characterized in that, The catalyst is one or both of zinc acetate and manganese acetate.

8. The method for preparing graphene-functionalized reinforced modified polyester fiber according to claim 7, characterized in that, Includes the following steps: 1) Take 50-200g of dimethyl terephthalate, 34-136g of ethylene glycol, and 0.09-0.36g of zinc acetate and add them to the reaction vessel. Perform transesterification reaction at 200-250℃ for 1-4 hours. Then add 0.25-9.0g of multi-component composite modifier, stir evenly, heat to 255-290℃, and polycondense for 1-4 hours. After the reaction is completed, pressurize with nitrogen to discharge the material, cool it, and granulate it to obtain functionalized modified polyester masterbatch. 2) The functionalized modified polyester masterbatch is dried at 80-110℃ for 2-8 hours, and then melt-spun, wound and stretched in a melt spinning machine to obtain graphene functionalized reinforced modified polyester fiber; wherein the spinning temperature is 270-300℃, the winding rate is 600-2400m / min, the stretching ratio is 1-3 times, and the stretching rate is 350-1400m / min.

9. A graphene-functionalized reinforced modified polyester fiber, characterized in that, It is prepared by the method described in any one of claims 1-8.

Images