Antibacterial sunscreen composite fabric and preparation method thereof

Abstract

This invention relates to the field of layered materials technology and discloses an antibacterial and sun-protective composite fabric and its preparation method. The preparation method of the antibacterial and sun-protective composite fabric includes the following steps: preparing a spinning solution using recycled flax fiber and chlorinated organic-inorganic composite material as raw materials; spinning to obtain a cooling antibacterial regenerated fiber; blending cotton fiber and the cooling antibacterial regenerated fiber to obtain an inner layer; impregnating the inner layer in a protective liquid, and after impregnation, pre-baking and baking to obtain a modified inner layer; blending modified polyester fiber and the cooling antibacterial regenerated fiber to obtain a surface layer; impregnating the surface layer in a hydrophobic finishing agent, and after impregnation, pre-baking and baking to obtain a modified surface layer; bonding the modified inner layer and the modified surface layer together, aligning the layers, and laminating to obtain the antibacterial and sun-protective composite fabric. The antibacterial and sun-protective composite fabric of this invention has excellent long-lasting antibacterial properties, sun protection, and a cooling thermal conductivity, and also possesses hydrophobic and stain-resistant properties and wearing comfort.

Description

Technical Field

[0001] This invention relates to the field of layered materials technology, specifically to an antibacterial and sun-protective composite fabric and its preparation method. Background Technology

[0002] There are many varieties of textile fabrics. As people's living standards improve, the demand for textile fabrics is developing towards fashion, diversification and functionality. For example, after a long period of use, fabrics are prone to the growth of a large number of bacteria or microorganisms, which will affect their practicality and safety. Therefore, antibacterial fabrics are becoming increasingly popular.

[0003] For example, Chinese patent CN106515152B describes a method for preparing a highly breathable and antibacterial functional composite fabric, belonging to the field of textile fabric technology. This invention involves polymerizing polyether diol and diisocyanate in a reactor, adding dimethylacetamide and stirring, then reacting it with ethylenediamine and cyclohexylamine under heat to obtain a thermoplastic polyurethane elastomer. Polyester staple fiber, jade fiber, etc., are then mixed, sprayed with an antibacterial aqueous solution, and baked. After twisting, spinning, and setting, a structure with inner and outer functional fabrics and a middle layer of thermoplastic polyurethane elastomer is obtained through hot-melt bonding, resulting in a highly breathable and antibacterial functional composite fabric. However, the use of antibacterial finishing agents on both inner and outer layers can weaken the antibacterial effect during wear and washing. Furthermore, with the depletion of the ozone layer in recent years, its ability to absorb and block short-wave ultraviolet radiation has decreased. Long-term exposure to ultraviolet radiation can cause skin problems and increase the risk of skin cancer. Therefore, while addressing the issue of durable antibacterial properties, improving the fabric's sun protection performance is also crucial. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a method for preparing an antibacterial and sun-protective composite fabric, comprising the following steps:

[0005] Step (1): A spinning solution is prepared using recycled flax fiber, 1-butyl-3-methylimidazolium acetate, and chlorinated organic-inorganic composite material as raw materials. The solution is then spun to obtain a cooling, antibacterial, regenerated fiber. The preparation method of the chlorinated organic-inorganic composite material includes the following steps:

[0006] Step B1: Guanidine carbonate reacts with α-acetyl-γ-butyrolactone to give an intermediate product; the intermediate product reacts with acryloyl chloride to give an N-haloamine precursor.

[0007] Step B2: 4-Aminobutane-1-thiol reacts with 4-pyridinecarboxaldehyde to give a Schiff base-pyridine compound, which then reacts with an N-haloamine precursor, and finally undergoes a quaternization reaction to give a Schiff base-pyridine quaternary ammonium salt-haloamine precursor.

[0008] Step B3: Melamine diborate is prepared using boric acid and melamine as raw materials. After the melamine diborate coats the nano copper powder, it is calcined to obtain modified copper powder. The modified copper powder is then processed to obtain aminated modified copper powder.

[0009] Aminated modified copper powder and graphene oxide were assembled to obtain a multi-component composite powder; glutaraldehyde was used as a crosslinking agent to combine the multi-component composite powder with a Schiff base-pyridine quaternary ammonium salt-haloamine compound precursor to obtain an organic-inorganic composite material, which was then treated with sodium hypochlorite to obtain a chlorinated organic-inorganic composite material.

[0010] Step (2): Blend cotton fiber and cool-feeling antibacterial regenerated fiber into yarn, knit to obtain the inner layer; immerse the inner layer in a protective liquid, and after immersion, pre-bake and bake to obtain the modified inner layer;

[0011] Step (3): Blend modified polyester fiber and cool-feeling antibacterial regenerated fiber into yarn, knit to obtain the surface layer; immerse the surface layer in a hydrophobic finishing agent, and after immersion, pre-bake and bake to obtain the modified surface layer;

[0012] The modified inner layer and modified outer layer are bonded together, aligned, and laminated to obtain an antibacterial and sun-protective composite fabric.

[0013] Preferably, in step (1), the preparation method of the cool-feeling antibacterial regenerated fiber is as follows: recycled flax fiber is mixed with 1-butyl-3-methylimidazolium acetate, stirred at a speed of 500-600 r / min for 1.5-2.5 h in a constant temperature water bath at 75-85℃, dimethyl sulfoxide is added, and stirring is continued for 2.5-3.5 h, then chlorinated organic-inorganic composite material is added, stirred for 20-40 min, and defoamed at 35-45℃ for 10-15 h to obtain spinning solution, and spinning is performed; wherein, in the spinning solution, the mass ratio of recycled flax fiber, 1-butyl-3-methylimidazolium acetate, dimethyl sulfoxide, and chlorinated organic-inorganic composite material is 1:(18-22):(54-66):(0.5-0.7).

[0014] Preferably, in step (1), the preparation method of the chlorinated organic-inorganic composite material is as follows:

[0015] Step B1: Guanidine carbonate, α-acetyl-γ-butyrolactone, triethylamine, and ethanol are mixed in a mass ratio of (11.3-22.6):(2.4-4.8):(3.8-7.6):(23-46). The mixture is stirred at 28-32℃ for 40-80 min, then the temperature is raised to 75-85℃ and the reaction is stirred for 20-30 h to obtain a pale yellow suspension. The suspension is filtered, washed, and dried to obtain the intermediate product. The intermediate product is then added to tetrahydro-... Triethylamine was added to furan, and the mixture was stirred in an ice-water bath for 20-40 min. Acryloyl chloride was then added, and the mixture was stirred in an ice-water bath for 50-70 min, followed by stirring at room temperature for 20-24 h. The mixture was then filtered, washed, and vacuum dried to obtain the N-haloamine precursor. The mass ratio of the intermediate, tetrahydrofuran, triethylamine, and acryloyl chloride was (15-30):(150-250):(10.1-20.1):(9-18).

[0016] In the above process, guanidine carbonate and α-acetyl-γ-butyrolactone react to obtain an intermediate product; the hydroxyl group in the intermediate product reacts with the acyl chloride of acryloyl chloride to obtain an N-haloamine precursor containing an amino group and a carbon-carbon double bond.

[0017] Step B2: Add 4-aminobutane-1-thiol to ethanol, sonicate for 20-40 min, then add 4-pyridinecarboxaldehyde, stir and react at 50-60℃ for 8-12 h. After the reaction is complete, remove the solvent by vacuum distillation to obtain Schiff base-pyridine compound; wherein the mass ratio of 4-aminobutane-1-thiol, ethanol and 4-pyridinecarboxaldehyde is (10.5-21):(150-250):(10.7-21.4);

[0018] The N-haloamine precursor was added to ethanol, sonicated for 20-40 min, heated to 50-80℃, and then azobisisobutyronitrile and Schiff base-pyridine compound were added. The mixture was stirred for 3-5 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain the Schiff base-pyridine-haloamine precursor. The mass ratio of the N-haloamine precursor, ethanol, azobisisobutyronitrile, and Schiff base-pyridine compound was (11.2-22.4):(150-200):(0.2-0.5):(9.7-19.4).

[0019] Schiff base-pyridine-haloamine precursor and bromotetradecane were added to dimethyl sulfoxide at a mass ratio of (10.2-20.2):(10.4-17.3):(150-250) and reacted at 80-90℃ for 24-30 h. After the reaction was completed, the mixture was filtered, washed and dried to obtain Schiff base-pyridine quaternary ammonium salt-haloamine precursor.

[0020] In the above process, the amino group of 4-aminobutane-1-thiol reacts with the aldehyde group of 4-pyridinecarboxaldehyde to generate a Schiff base-pyridine compound; the thiol group in the Schiff base-pyridine compound undergoes a thiol-ene click reaction with the carbon-carbon double bond of the N-haloamine compound precursor to obtain the Schiff base-pyridine-haloamine compound precursor; the Schiff base-pyridine-haloamine compound precursor reacts with bromotetradecane through a quaternization reaction to generate a Schiff base-pyridine quaternary ammonium salt-haloamine compound precursor containing a long alkyl chain;

[0021] Step B3: Mix boric acid, melamine, and deionized water in a mass ratio of (1.9-3.8):(2.5-4.5):(200-300), heat to 100-110℃ and stir at 200-400 r / min for 7-9 h, cool naturally to room temperature, precipitate the crude product, filter, and dry to obtain melamine diborate.

[0022] Nano copper powder, melamine diborate, and deionized water are mixed in a mass ratio of (2-4):(0.2-0.4):(200-300) and stirred at a speed of 150-250 r / min. The mixture is heated at 240-260℃ until the deionized water is completely evaporated to obtain melamine diborate-coated copper powder. The melamine diborate-coated copper powder is heated to 900-1100℃ and kept in an argon and hydrogen flow for 2.5-3.5 h to obtain modified copper powder. The argon flow rate is 200 sccm and the hydrogen flow rate is 10 sccm.

[0023] Modified copper powder was ultrasonically mixed with 30wt% hydrogen peroxide aqueous solution at a mass ratio of 1:100 for 10-15 h, and reacted at 105-110℃ for 20-24 h. After the reaction was completed, hydroxylated modified copper powder was obtained. Hydroxylated modified copper powder, ethanol, and N-(2-aminoethyl)-3-aminopropyltrimethoxysilane were mixed at a mass ratio of (15-20):(50-60):(1.5-2.5), and stirred and reacted at 60-70℃ for 30-60 min in a light-protected environment and nitrogen atmosphere. After filtration, washing, and drying, amino-modified copper powder was obtained.

[0024] In the above process, melamine diborate generated by the reaction of boric acid and melamine is coated on copper powder. Melamine diborate serves as a precursor for boron nitride, and nano-boron nitride is grown in situ on the copper powder to obtain modified copper powder. The modified copper powder is then treated with N-(2-aminoethyl)-3-aminopropyltrimethoxysilane to introduce amino groups onto the surface of the modified copper powder.

[0025] Aminated modified copper powder and graphene oxide powder were ultrasonically dispersed in deionized water to obtain aminated modified copper powder dispersion and graphene oxide dispersion with concentrations of 2-5 mg / mL. The aminated modified copper powder dispersion was added dropwise to the graphene oxide dispersion at a rate of 1-2 mL / min, stirred at a speed of 400-600 r / min for 5-15 min, ultrasonically treated at a power of 150-250 W for 5-15 min, and then ultrasonically treated in an ice-water bath at a pH of 7-8 and an ultrasonic power of 50-70 W for 10-20 min. After centrifugation, the supernatant was removed, and the mixture was dried to obtain a multi-component composite powder.

[0026] The multi-component composite powder was mixed with ethanol containing 5 wt% glutaraldehyde at a ratio of (2-4) g:(30-60) mL and reacted at 95-105℃ for 8-12 h. After filtration and washing, the modified multi-component composite powder was obtained. The Schiff base-pyridine quaternary ammonium salt-haloamine compound precursor, dimethyl sulfoxide, and the modified multi-component composite powder were mixed at a mass ratio of (5-10):(100-120):(3-5) and stirred at 45-55℃ for 10-16 h. After filtration, washing, and drying, the organic-inorganic composite material was obtained.

[0027] The organic-inorganic composite material was added to a 10wt% sodium hypochlorite aqueous solution at a solid-liquid ratio of 1:(25-35), and the pH was adjusted to 7 with acetic acid. The mixture was stirred at room temperature for 1.5-2.5 h, filtered, washed, and dried to obtain the chlorinated organic-inorganic composite material.

[0028] In the above process, the aminated modified copper powder and graphene oxide powder self-assemble through hydrogen bonds and electrostatic interactions between amino and carboxyl groups, depositing the aminated modified copper powder on graphene oxide nanoparticles to form a multi-component composite powder. Using glutaraldehyde as a crosslinking agent, it reacts with the Schiff base-pyridine quaternary ammonium salt-haloamine compound precursor and the amino groups of the multi-component composite powder to graft the Schiff base-pyridine quaternary ammonium salt-haloamine compound precursor onto the multi-component composite powder and introduce more Schiff base structures to obtain an organic-inorganic composite material. Furthermore, the organic-inorganic composite material is subjected to chlorination treatment with sodium hypochlorite, and the -NH of the N-haloamine compound precursor in the Schiff base-pyridine quaternary ammonium salt-haloamine compound precursor on its surface is converted to -NCl.

[0029] Preferably, in step (2), the mass ratio of cotton fiber to cool-feeling antibacterial regenerated fiber is (60-70):(30-40), and the English count of the blended yarn is 40-60S; the weight of the inner layer is 80-100g / m². 2 The protective liquid is prepared by mixing polydimethylsiloxane, cyclohexane, and double-doped carbon dots in a mass ratio of (8-12):(88-92):(0.5-2).

[0030] Preferably, in step (2), the impregnation conditions are: impregnation at room temperature for 20-30 minutes, one impregnation and one rolling, with a roll-off rate of 90-95% and a bath ratio of 1:(15-25).

[0031] Preferably, in step (3), the mass ratio of the modified polyester fiber to the cool-feeling antibacterial regenerated fiber is (75-85):(15-25), the English count of the blended yarn is 60-80S, and the basis weight of the surface layer is 100-120g / m². 2 The hydrophobic finishing agent is obtained by mixing polydimethylsiloxane and isopropanol in a volume ratio of 10:25.

[0032] Preferably, in step (3), the impregnation conditions are: impregnation at room temperature for 20-30 minutes, one impregnation and one rolling, with a roll residue of 75-88% and a bath ratio of 1:(15-25).

[0033] Preferably, in step (3), the method for preparing the modified polyester fiber includes the following steps:

[0034] Step A1: Wash freshly picked guava leaves with water, dry them in the sun, grind them to obtain guava leaf powder, mix the guava leaf powder with deionized water, boil at 90-95℃ for 4.5-5.5h, filter, heat at 65-75℃ to concentrate the filtrate to 5-10mL, then add manganese sulfate monohydrate and titanium dioxide nanoparticles, keep at 180-190℃ for 5-6h, filter, dry, and obtain double-doped carbon dots; wherein, the mass ratio of guava leaf powder, deionized water, manganese sulfate monohydrate, and titanium dioxide nanoparticles is (15-20):(60-80):(0.03-0.06):(0.05-0.08);

[0035] The double-doped carbon dots, activated polyester fibers, p-toluenesulfonic acid, and cyclohexane were mixed in a mass ratio of (1-2):(10-15):(0.1-0.2):(150-200). The mixture was stirred and reacted at 120-140℃ for 3-5 hours under a nitrogen atmosphere. After the reaction was completed, the mixture was filtered, washed, and dried to obtain surface-modified polyester fibers.

[0036] In the above process, guava leaf powder, manganese sulfate monohydrate and titanium dioxide nanoparticles were used as raw materials to prepare carbon dots containing manganese and nano titanium dioxide. The carboxyl groups on the surface of the activated polyester fiber and the hydroxyl groups of the double-doped carbon dots underwent an esterification reaction, and the double-doped carbon dots were grafted onto the polyester fiber by the formation of chemical bonds.

[0037] Step A2: Mix 3-aminopropyltriethoxysilane and ethanol at a ratio of (8-16) g:(20-50) mL, then add acetic acid to adjust the pH to 3.8-4.2 to obtain a mixture; add surface-modified polyester fibers to the above mixture at a solid-liquid ratio of 1:(15-25), immerse at 65-75℃ for 40-80 min, remove, wash, and dry to obtain amino-modified polyester fibers;

[0038] Protocatechuic aldehyde was dissolved in deionized water to obtain a treatment solution with a concentration of 5-8 mg / mL. Amino-modified polyester fibers were added to the treatment solution at a solid-liquid ratio of 1:(10-20). The solution was stirred at 45-55℃ for 10-15 h, then removed and dried at 55-65℃ for 50-70 min. After washing, protocatechuic aldehyde-modified polyester fibers were obtained. The protocatechuic aldehyde-modified polyester fibers were then soaked in a 0.2 mol / L ferric chloride aqueous solution at 75-85℃ with a solid-liquid ratio of 1:(10-20) for 1-2 h. After soaking, the fibers were dried at 55-65℃ for 50-70 min, washed, and dried again to obtain modified polyester fibers.

[0039] In the above process, 3-aminopropyltriethoxysilane hydrolyzes to generate silanol bonds, which react with the surface-modified polyester fibers to introduce amino groups into the surface-modified polyester fibers, thus obtaining amino-modified polyester fibers. The amino groups of the amino-modified polyester fibers react with the aldehyde groups of protocatechuic aldehyde to introduce a catechol structure into the surface of the polyester fibers. Furthermore, the phenolic hydroxyl groups in the catechol structure chelate with the iron ions in ferric chloride to form modified polyester fibers.

[0040] Further, in step (3), the method for preparing the activated polyester fiber is as follows: the polyester fiber is immersed in a sodium hydroxide aqueous solution with a concentration of 20 g / L, and after alkali immersion treatment at 90-100℃ for 20-40 min, it is transferred into a deionized water mixture of choline chloride and oxalic acid, and deep-treated at 40-80℃ for 0.5-2 h, washed, and dried to obtain the activated polyester fiber. In the deionized water mixture of choline chloride and oxalic acid, the mass ratio of choline chloride to oxalic acid is 3:2, the total concentration of choline chloride and oxalic acid is 50 g / L, and the bath ratio of alkali immersion treatment and deep treatment is (25-35):1.

[0041] During the above process, the polyester fiber surface generates abundant hydroxyl and carboxyl groups after activation treatment.

[0042] The antibacterial and sun-protective composite fabric is prepared using the aforementioned method.

[0043] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0044] 1. This invention uses recycled flax fiber as raw material to prepare cool-feeling antibacterial regenerated fiber, avoiding the waste of natural fibers. It utilizes ionic liquid to dissolve cellulose, which has the advantages of good solubility, recyclability, and environmental friendliness.

[0045] 2. This invention involves in-situ growth of boron nitride nanoparticles on copper powder to obtain modified copper powder. The boron nitride coating prevents oxidation of the copper nanoparticles, maintaining stable antibacterial properties. Furthermore, the modified copper powder exhibits better thermal conductivity compared to regular copper powder. The modified copper powder is then deposited onto thermally conductive and antibacterial graphene oxide nanosheets through self-assembly, forming "point and surface" thermal conduction channels, which facilitates the establishment of thermal conduction paths, resulting in a multi-component composite powder with high thermal conductivity and antibacterial rate. Further, the multi-component composite powder is combined with a Schiff base-pyridine quaternary ammonium salt-haloamine compound precursor and then chlorinated to obtain a chlorinated organic-inorganic composite material. Organic grafting of the inorganic multi-component composite powder improves the interfacial effect between the multi-component composite powder and cellulose, enhancing the chlorinated organic-inorganic composite material's properties. The inorganic composite material forms hydrogen bonds with the cellulose surface, and the pyridine quaternary ammonium salt, N-haloamine, and Schiff base in the chlorinated organic-inorganic composite material have complementary and synergistic effects. The quaternary ammonium salt attracts bacteria to the N-haloamine site through electrostatic attraction, rapidly killing them and thus effectively improving its antibacterial activity. The presence of the Schiff base structure can effectively improve the stability and durability of the antibacterial agent and enhance the antibacterial and antioxidant activity of the quaternary ammonium salt. Therefore, spinning the chlorinated organic-inorganic composite material of the present invention with recycled flax fiber yields a cool-feeling antibacterial regenerated fiber with a long-lasting antibacterial effect and a thermally conductive cooling effect. Furthermore, the long alkyl chains in the Schiff base-pyridine quaternary ammonium salt-haloamine compound endow the cool-feeling antibacterial regenerated fiber with good hydrophobicity and softness.

[0046] 3. This invention uses guava leaves as raw material to prepare dual-doped carbon dots containing nano-titanium dioxide and manganese. The doping of nano-titanium dioxide and manganese promotes the generation of active oxygen, thereby improving the antibacterial effect of the carbon dots. Furthermore, the doping of nano-titanium dioxide can improve the ultraviolet shielding efficiency of the carbon dots. Grafting the dual-doped carbon dots onto polyester fibers yields surface-modified polyester fibers, which can improve the antibacterial and sun protection properties of the polyester fibers. In addition, protocatechuic aldehyde is inoculated onto the surface-modified polyester fibers and iron ions are chelated. The protocatechuic aldehyde structure has excellent antibacterial and ultraviolet absorption capabilities due to its benzene ring and phenolic hydroxyl groups. The chelation of iron ions can enhance bacterial adsorption and improve the antibacterial effect. On the other hand, iron ions can increase the reflection and scattering of ultraviolet rays on the surface of polyester fibers, thereby improving the sun protection effect. Therefore, the modified polyester fibers of this invention have permanent antibacterial and sun protection properties.

[0047] 4. A cotton fiber and a cooling antibacterial regenerated fiber are blended to obtain an inner layer. The inner layer is then immersed in a protective liquid composed of polydimethylsiloxane, cyclohexane, and dual-doped carbon dots, which imparts better hydrophobicity, softness, and antibacterial and sun protection effects to the inner layer. A modified polyester fiber and a cooling antibacterial regenerated fiber are blended to obtain an outer layer. The outer layer is then immersed in a hydrophobic finishing agent, which imparts better hydrophobicity and softness to the outer layer. Therefore, the antibacterial and sun protection composite fabric of the present invention not only has excellent long-lasting antibacterial properties, sun protection, and thermal cooling effects, but also has hydrophobic and stain-resistant properties and wearing comfort. Attached Figure Description

[0048] Figure 1 This is a process flow diagram of the preparation method of the antibacterial and sun-protective composite fabric of the present invention;

[0049] Figure 2 This is a schematic diagram illustrating the synthesis of the N-haloamine compound precursor of the present invention;

[0050] Figure 3 This is a schematic diagram illustrating the synthesis of the Schiff base-pyridine quaternary ammonium salt-haloamine compound precursor of the present invention;

[0051] Figure 4 This is a comparison chart of the antibacterial rate test results of the antibacterial and sun-protective composite fabrics of Examples 3-5 and Comparative Examples 7-13 of the present invention;

[0052] Figure 5 This is a comparison chart of the UPF test results of the antibacterial and sun-protective composite fabrics of Examples 3-5 and Comparative Examples 7-13 of the present invention;

[0053] Figure 6 This is a comparison chart of the contact cooling coefficient test results of the antibacterial and sun-protective composite fabrics of Examples 3-5 and Comparative Examples 7-13 of the present invention. Detailed Implementation

[0054] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0055] Example 1

[0056] This embodiment discloses a method for preparing modified polyester fibers, including the following steps:

[0057] Step A1: Wash freshly picked guava leaves with water and dry them in the sun. Grind them to obtain guava leaf powder. Mix 17.5g of guava leaf powder with 70g of deionized water and boil at 93℃ for 5 hours. Filter the mixture and heat it at 70℃ to concentrate the filtrate to 7.5mL. Then add 0.04g of manganese sulfate monohydrate and 0.07g of titanium dioxide nanoparticles. Keep the mixture at 185℃ for 5.5 hours, filter the mixture, and dry it to obtain double-doped carbon dots.

[0058] Polyester fibers were immersed in a 20 g / L sodium hydroxide aqueous solution and treated with alkali at 95°C for 30 min. Then, they were transferred to a deionized water mixture of choline chloride and oxalic acid and treated with deep treatment at 60°C for 1 h. After washing and drying, activated polyester fibers were obtained. The mass ratio of choline chloride to oxalic acid in the deionized water mixture of choline chloride and oxalic acid was 3:2, the total concentration of choline chloride and oxalic acid was 50 g / L, and the bath ratio of alkali immersion treatment and deep treatment was 30:1.

[0059] 1.5g of double-doped carbon dots, 12.5g of activated polyester fiber, 0.15g of p-toluenesulfonic acid, and 180g of cyclohexane were mixed and stirred at 130°C for 4 hours under a nitrogen atmosphere. After the reaction was completed, the mixture was filtered, washed, and dried to obtain surface-modified polyester fiber.

[0060] Step A2: Mix 3-aminopropyltriethoxysilane and ethanol at a ratio of 12g:35mL, then add acetic acid to adjust the pH to 4 to obtain a mixture; add the surface-modified polyester fiber to the above mixture at a solid-liquid ratio of 1:20, immerse it at 70℃ for 60min, remove it, wash it, and dry it to obtain amino-modified polyester fiber.

[0061] Protocatechuic aldehyde was dissolved in deionized water to obtain a treatment solution with a concentration of 6.5 mg / mL. Amino-modified polyester fiber was added to the treatment solution at a solid-liquid ratio of 1:15. After stirring at 50°C for 12.5 h, the solution was removed, dried at 60°C for 60 min, and washed to obtain protocatechuic aldehyde-modified polyester fiber. The protocatechuic aldehyde-modified polyester fiber was then treated by soaking in a 0.2 mol / L ferric chloride aqueous solution at 80°C with a solid-liquid ratio of 1:15 for 1.5 h. After soaking, the solution was removed, dried at 60°C for 60 min, washed, and dried to obtain modified polyester fiber.

[0062] Example 2

[0063] This embodiment discloses a method for preparing a chlorinated organic-inorganic composite material, including the following steps:

[0064] Step B1: 17g guanidine carbonate, 3.6g α-acetyl-γ-butyrolactone, 5.7g triethylamine, and 34.5g ethanol were stirred and mixed at 30℃ for 60min, then the temperature was raised to 80℃ and stirred for 25h to obtain a pale yellow suspension. The suspension was filtered, and the obtained solid was washed 6 times with ethanol and dried under vacuum at 50℃ for 12h to obtain an intermediate product. 22.5g of the intermediate product was added to 200g tetrahydrofuran, and 15.1g triethylamine was added. The mixture was stirred in an ice-water bath for 30min, and 13.5g acryloyl chloride was added. The mixture was stirred in an ice-water bath for 60min, and then stirred at room temperature for 22h. The mixture was filtered, and the filtered product was washed with tetrahydrofuran and acetone in sequence and dried under vacuum to obtain an N-haloamine precursor.

[0065] Step B2: 115.8 g of 4-aminobutane-1-thiol was added to 200 g of ethanol and sonicated for 30 min. Then 16.1 g of 4-pyridinecarboxaldehyde was added, and the mixture was stirred at 55 °C for 10 h. After the reaction was completed, the solvent was removed by vacuum distillation at 70 °C to obtain the Schiff base-pyridine compound. 16.8 g of the N-haloamine compound precursor was added to 175 g of ethanol and sonicated for 30 min. The mixture was heated to 65 °C, and then 0.3 g of azobisisobutyronitrile and 13.6 g of the Schiff base-pyridine compound were added. The mixture was stirred for 4 h. After the reaction was completed, the mixture was filtered, and the resulting solid was washed four times with ethanol and dried under vacuum at 55 °C to obtain the Schiff base-pyridine-haloamine compound precursor.

[0066] 15.2 g of Schiff base-pyridine-haloamine precursor and 13.9 g of bromotetradecane were added to 200 g of dimethyl sulfoxide and reacted at 85 °C for 26 h. After the reaction was completed, the mixture was filtered, and the resulting solid product was washed with ethanol and dried to obtain Schiff base-pyridine quaternary ammonium salt-haloamine precursor.

[0067] Step B3: Add 2.9g boric acid and 3.5g melamine to 250g deionized water, heat to 105℃ and stir at 300r / min for 8h, cool naturally to room temperature, precipitate crude product, filter, and dry the obtained crude product at 75℃ for 25h to obtain melamine diborate.

[0068] 3g of nano copper powder, 0.3g of melamine diborate, and 250g of deionized water were mixed and stirred at 200r / min. The mixture was heated at 250℃ until the deionized water was completely evaporated to obtain melamine diborate-coated copper powder. The melamine diborate-coated copper powder was placed in a tube furnace and heated to 1000℃. The furnace was kept in an argon and hydrogen flow for 3 hours to obtain modified copper powder. The argon flow rate was 200sccm and the hydrogen flow rate was 10sccm.

[0069] Modified copper powder was ultrasonically mixed with 30wt% hydrogen peroxide aqueous solution at a mass ratio of 1:100 for 12.5 h, and reacted at 108℃ for 22 h. After the reaction was completed, hydroxylated modified copper powder was obtained. Hydroxylated modified copper powder, ethanol, and N-(2-aminoethyl)-3-aminopropyltrimethoxysilane were mixed at a mass ratio of 17.5:55:2 and stirred at 65℃ for 45 min in a light-protected environment and nitrogen atmosphere. After filtration, washing, and drying, amino-modified copper powder was obtained.

[0070] Aminated modified copper powder and graphene oxide powder were ultrasonically dispersed in deionized water to obtain aminated modified copper powder dispersion and graphene oxide dispersion, both with a concentration of 3.5 mg / mL. The aminated modified copper powder dispersion was added dropwise to the graphene oxide dispersion at a rate of 1.5 mL / min, stirred at 500 r / min for 10 min, ultrasonically treated at 200 W for 10 min, and then ultrasonically treated in an ice-water bath at pH 7.5 and ultrasonic power of 60 W for 15 min. After centrifugation, the supernatant was removed, and the powder was dried to obtain a multi-component composite powder.

[0071] 3g of multi-component composite powder was dispersed in 45mL of ethanol containing 5wt% glutaraldehyde and reacted at 100℃ for 10h. After filtration and washing, the modified multi-component composite powder was obtained. 7.5g of Schiff base-pyridine quaternary ammonium salt-haloamine compound precursor was added to 110g of dimethyl sulfoxide, and then 4g of modified multi-component composite powder was added. The mixture was stirred and reacted at 50℃ for 13h. After filtration, washing and drying, the organic-inorganic composite material was obtained.

[0072] The organic-inorganic composite material was added to a 10wt% sodium hypochlorite aqueous solution at a solid-liquid ratio of 1:30, and the pH was adjusted to 7 with acetic acid. The mixture was stirred at room temperature for 2 hours, filtered, washed, and dried to obtain the chlorinated organic-inorganic composite material.

[0073] Example 3

[0074] This embodiment discloses a method for preparing an antibacterial and sun-protective composite fabric, including the following steps:

[0075] Step (1): The recycled flax fiber is mixed with 1-butyl-3-methylimidazolium acetate and stirred at 500 r / min for 1.5 h in a constant temperature water bath at 75 °C. Dimethyl sulfoxide is added and stirring is continued for 2.5 h. Then, chlorinated organic-inorganic composite material is added and stirred for 20 min. The mixture is defoamed at 40 °C for 10 h to obtain a spinning solution. The fiber is spun to obtain a cool-feeling antibacterial regenerated fiber. The mass ratio of recycled flax fiber, 1-butyl-3-methylimidazolium acetate, dimethyl sulfoxide, and chlorinated organic-inorganic composite material in the spinning solution is 1:18:54:0.5.

[0076] Step (2): Blend cotton fiber and cool-feeling antibacterial regenerated fiber at a mass ratio of 60:40 to form a yarn with an English count of 40S, knit it, and obtain a weight of 80g / m². 2 The inner layer is immersed in a protective liquid. After immersion, it is pre-baked and then baked to obtain the modified inner layer. The protective liquid is prepared by mixing polydimethylsiloxane, cyclohexane, and dual-doped carbon dots in a mass ratio of 8:92:0.5. The immersion conditions are: immersion at room temperature for 20 minutes, one immersion and one roll, with a roll residue of 90% and a bath ratio of 1:15.

[0077] Step (3): Blend modified polyester fiber and cool-feeling antibacterial regenerated fiber at a mass ratio of 75:25 to form a yarn with an English count of 60S, knit it, and obtain a weight of 100g / m². 2 The surface layer is immersed in a hydrophobic finishing agent. After immersion, it is pre-baked and baked to obtain a modified surface layer. The hydrophobic finishing agent is obtained by mixing polydimethylsiloxane and isopropanol in a volume ratio of 10:25. The immersion conditions are: immersion at room temperature for 20 minutes, one dip and one roll, roll residue of 75%, and bath ratio of 1:15.

[0078] The modified inner layer and modified outer layer are bonded together, aligned, and laminated to obtain an antibacterial and sun-protective composite fabric.

[0079] Example 4

[0080] This embodiment discloses a method for preparing an antibacterial and sun-protective composite fabric, including the following steps:

[0081] Step (1): The recycled flax fiber is mixed with 1-butyl-3-methylimidazolium acetate and stirred at 600 r / min for 2.5 h in a constant temperature water bath at 85 °C. Dimethyl sulfoxide is added and stirring is continued for 3.5 h. Then, chlorinated organic-inorganic composite material is added and stirred for 40 min. The mixture is defoamed at 45 °C for 15 h to obtain spinning solution. Spinning is performed to obtain cool-feeling antibacterial regenerated fiber. The mass ratio of recycled flax fiber, 1-butyl-3-methylimidazolium acetate, dimethyl sulfoxide, and chlorinated organic-inorganic composite material in the spinning solution is 1:22:66:0.7.

[0082] Step (2): Blend cotton fiber and cool-feeling antibacterial regenerated fiber at a mass ratio of 70:30 to form a yarn with an English count of 60S, knit it, and obtain a weight of 100g / m². 2 The inner layer is immersed in a protective liquid. After immersion, it is pre-baked and then baked to obtain the modified inner layer. The protective liquid is prepared by mixing polydimethylsiloxane, cyclohexane, and dual-doped carbon dots in a mass ratio of 12:88:2. The immersion conditions are: immersion at room temperature for 30 minutes, one immersion and one roll, with a roll residue of 95% and a bath ratio of 1:25.

[0083] Step (3): Blend modified polyester fiber and cool-feeling antibacterial regenerated fiber at a mass ratio of 85:15 to form a yarn with an English count of 80S, knit it, and obtain a weight of 120g / m². 2 The surface layer is immersed in a hydrophobic finishing agent. After immersion, it is pre-baked and baked to obtain a modified surface layer. The hydrophobic finishing agent is obtained by mixing polydimethylsiloxane and isopropanol in a volume ratio of 10:25. The immersion conditions are: immersion at room temperature for 30 minutes, one immersion and one roll, with a roll-off rate of 88% and a bath ratio of 1:25.

[0084] The modified inner layer and modified outer layer are bonded together, aligned, and laminated to obtain an antibacterial and sun-protective composite fabric.

[0085] Example 5

[0086] This embodiment discloses a method for preparing an antibacterial and sun-protective composite fabric, including the following steps:

[0087] Step (1): The recycled flax fiber is mixed with 1-butyl-3-methylimidazolium acetate and stirred at 550 r / min for 2 h in a constant temperature water bath at 80℃. Dimethyl sulfoxide is added and stirring is continued for 3 h. Then, chlorinated organic-inorganic composite material is added and stirred for 30 min. The mixture is defoamed at 40℃ for 12.5 h to obtain spinning solution. Spinning is performed to obtain cool-feeling antibacterial regenerated fiber. The mass ratio of recycled flax fiber, 1-butyl-3-methylimidazolium acetate, dimethyl sulfoxide and chlorinated organic-inorganic composite material in the spinning solution is 1:20:60:0.6.

[0088] Step (2): Blend cotton fiber and cool-feeling antibacterial regenerated fiber at a mass ratio of 65:35 to form a yarn with an English count of 50S, knit it, and obtain a weight of 90g / m². 2 The inner layer is immersed in a protective liquid, and after immersion, it is pre-baked and baked to obtain the modified inner layer. The protective liquid is prepared by mixing polydimethylsiloxane, cyclohexane, and dual-doped carbon dots in a mass ratio of 10:90:1.2. The immersion conditions are: immersion at room temperature for 25 minutes, one immersion and one roll, with a roll residue of 93% and a bath ratio of 1:20.

[0089] Step (3): Blend modified polyester fiber and cool-feeling antibacterial regenerated fiber at a mass ratio of 80:20 to form a yarn with an English count of 90S, knit it, and obtain a weight of 110g / m². 2 The surface layer is immersed in a hydrophobic finishing agent. After immersion, it is pre-baked and baked to obtain a modified surface layer. The hydrophobic finishing agent is obtained by mixing polydimethylsiloxane and isopropanol in a volume ratio of 10:25. The immersion conditions are: immersion at room temperature for 25 minutes, one immersion and one roll, with a roll-off rate of 81% and a bath ratio of 1:20.

[0090] The modified inner layer and modified outer layer are bonded together, aligned, and laminated to obtain an antibacterial and sun-protective composite fabric.

[0091] The modified polyester fiber and chlorinated organic-inorganic composite material in Examples 3-5 above were prepared using the modified polyester fiber prepared in Example 1 and the chlorinated organic-inorganic composite material prepared in Example 2, respectively.

[0092] Comparative Example 1

[0093] Compared with Example 1, Comparative Example 1 did not add manganese sulfate monohydrate during the preparation of dual-doped carbon dots, while other conditions remained unchanged.

[0094] Comparative Example 2

[0095] Compared with Example 1, Comparative Example 2 did not add titanium dioxide nanoparticles during the preparation of dual-doped carbon dots, while other conditions remained unchanged.

[0096] Comparative Example 3

[0097] Compared with Example 1, Comparative Example 3 used amino-modified polyester fiber instead of protocatechuic aldehyde-modified polyester fiber in the preparation of modified polyester fiber, while other conditions remained unchanged.

[0098] Comparative Example 4

[0099] Compared with Example 2, in the preparation of organic-inorganic composite materials, Comparative Example 4 used Schiff base-pyridine-haloamine compound precursor instead of Schiff base-pyridine quaternary ammonium salt-haloamine compound precursor, while other conditions remained unchanged.

[0100] Comparative Example 5

[0101] Compared with Example 2, Comparative Example 5 used nano copper powder instead of hydroxylated modified copper powder in the preparation of aminated modified copper powder, while other conditions remained unchanged.

[0102] Comparative Example 6

[0103] Compared with Example 2, Comparative Example 6 used aminated modified copper powder instead of multi-component composite powder in the preparation of organic-inorganic composite material, while other conditions remained unchanged.

[0104] Comparative Example 7

[0105] Compared with Example 5, Comparative Example 7 used the modified polyester fiber prepared in Comparative Example 1 in the preparation of the surface layer, while other conditions remained unchanged.

[0106] Comparative Example 8

[0107] Compared with Example 5, Comparative Example 8 used the modified polyester fiber prepared in Comparative Example 2 in the preparation of the surface layer, while other conditions remained unchanged.

[0108] Comparative Example 9

[0109] Compared with Example 5, Comparative Example 9 used protocatechuic aldehyde modified polyester fiber instead of modified polyester fiber in the preparation of the surface layer, while other conditions remained unchanged.

[0110] Comparative Example 10

[0111] Compared with Example 5, Comparative Example 10 used the modified polyester fiber prepared in Comparative Example 3 in the preparation of the surface layer, while other conditions remained unchanged.

[0112] Comparative Example 11

[0113] Compared with Example 5, Comparative Example 11 used the chlorinated organic-inorganic composite material prepared in Comparative Example 4 in the process of producing cool-feeling antibacterial regenerated fiber, while other conditions remained unchanged.

[0114] Comparative Example 12

[0115] Compared with Example 5, Comparative Example 12 used the chlorinated organic-inorganic composite material prepared in Comparative Example 5 in the process of producing cool-feeling antibacterial regenerated fiber, while other conditions remained unchanged.

[0116] Comparative Example 13

[0117] Compared with Example 5, Comparative Example 13 used the chlorinated organic-inorganic composite material prepared in Comparative Example 6 in the process of producing cool-feeling antibacterial regenerated fiber, while keeping other conditions unchanged.

[0118] In the above examples and comparative examples, the graphene oxide powder, with a purity of 99% and a particle size of >5μm, catalog number 133423, brand: Kramar, was sourced from Shanghai Ziyi Reagent Factory; the nano-copper powder, with a spherical microstructure and an average particle size of 100nm, catalog number LF-Cu-N100, was sourced from Qinghe County Chaotai Metal Materials Co., Ltd.; the recycled flax fiber, which was degummed recycled flax fiber, was sourced from Hangzhou Shanglu Silk Co., Ltd.; and the titanium dioxide nanoparticles, which were high-purity anatase type with a particle size of 10-20nm, were sourced from Qinghe County Chaotai Metal Materials Co., Ltd.

[0119] Experimental Example

[0120] Test 1: Performance tests were conducted on the antibacterial and sun-protective composite fabrics prepared in Examples 3-5 and Comparative Examples 7-13.

[0121] 1. Antibacterial performance test: The antibacterial effect of each group of fabric samples against Escherichia coli and Staphylococcus aureus after 100 washes was tested according to GB / T 20944.3-2008.

[0122] 2. Sun protection performance test: UPF (ultraviolet protection factor) test was conducted in accordance with GB / T 18830-2009, with a sample size of 5cm×5cm.

[0123] 3. Contact cooling coefficient: The test was conducted in accordance with GB / T 35263-2017. The temperature of the sample stage was 20℃ and the temperature of the thermal detection plate was 35℃. The contact cooling coefficient was tested using a contact cooling and warming tester.

[0124] The test results are shown in Table 1:

[0125] Table 1

[0126]

[0127] As shown in Table 1, the antibacterial and sun-protective composite fabrics prepared in Examples 3-5 of this invention have excellent long-lasting antibacterial properties, sun protection properties, and a cooling sensation. A comparison between Comparative Examples 7-8 and Example 5 shows that the doping of nano-titanium dioxide and manganese in the dual-doped carbon dots improves the antibacterial effect of the carbon dots by promoting the generation of active oxygen. Furthermore, the doping of nano-titanium dioxide improves the ultraviolet shielding efficiency of the carbon dots. Therefore, grafting dual-doped carbon dots onto polyester fibers to obtain surface-modified polyester fibers can improve the antibacterial and sun-protective properties of the polyester fibers. A comparison between Comparative Examples 9-10 and Example 5 shows that incorporating protocatechuic aldehyde and chelating iron ions onto the surface-modified polyester fibers, the protocatechuic aldehyde structure, due to its benzene ring and phenolic hydroxyl groups, has excellent antibacterial and ultraviolet absorption capabilities. The chelation of iron ions enhances the adsorption of bacteria and improves the antibacterial effect. On the other hand, iron ions increase the reflection and scattering of ultraviolet rays on the surface of the polyester fibers, improving the sun protection effect. A comparison between Comparative Example 11 and Example 5 shows that... As can be seen, the quaternary ammonium salt in the chlorinated organic-inorganic composite material attracts bacteria to the N-halogen amine sites through electrostatic attraction, rapidly killing them and thus effectively improving its antibacterial activity, thereby improving the antibacterial performance of the fabric. As can be seen from the comparison between Comparative Example 12 and Example 5, boron nitride coating avoids the oxidation of nano copper powder, maintaining its stable antibacterial performance. Moreover, the modified copper powder has better thermal conductivity than copper powder, thereby improving the contact cooling coefficient and antibacterial properties of the fabric. As can be seen from the comparison between Comparative Example 13 and Example 5, depositing modified copper powder on graphene oxide nanosheets with thermal conductivity and antibacterial properties forms a thermally conductive channel with "points and surfaces". The combination of modified copper powder and graphene oxide is conducive to establishing a thermally conductive path, resulting in a multi-component composite powder with high thermal conductivity and antibacterial rate, thereby improving the contact cooling coefficient and antibacterial properties of the fabric.

[0128] Test 2: Hydrophobicity and softness tests were conducted on the antibacterial and sun-protective composite fabrics prepared in Examples 3-5.

[0129] 1. Hydrophobicity test: The water contact angle is measured using a 4μL water droplet with a water contact angle meter;

[0130] 2. Softness test: using The system performs hand property tests, sampling at a frequency of 10 times per second. The test samples are circular with an area of ​​approximately 100 square meters, conforming to the T / ZFB 003-2019 standard, and the softness of each group of fabrics is scored.

[0131] The test results are shown in Table 2:

[0132] Table 2

[0133] Water contact angle / ° Softness rating / points Example 3 163.6 74.84±0.22 Example 4 165.2 75.26±0.29 Example 5 164.4 75.92±0.26

[0134] As can be seen from the test results in Table 2, the antibacterial and sun-protective composite fabrics prepared in Examples 3-5 of the present invention have both good hydrophobicity, stain resistance and softness.

[0135] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing an antibacterial and sun-protective composite fabric, characterized in that, Includes the following steps: Step (1): Prepare spinning solution using recycled flax fiber, 1-butyl-3-methylimidazolium acetate, and chlorinated organic-inorganic composite material as raw materials; spin to obtain cool-feeling antibacterial regenerated fiber; wherein, the preparation method of chlorinated organic-inorganic composite material includes the following steps: Step B1: Guanidine carbonate reacts with α-acetyl-γ-butyrolactone to give an intermediate product; the intermediate product reacts with acryloyl chloride to give an N-haloamine precursor. Step B2: 4-Aminobutane-1-thiol reacts with 4-pyridinecarboxaldehyde to give a Schiff base-pyridine compound, which then reacts with an N-haloamine precursor, and finally undergoes a quaternization reaction to give a Schiff base-pyridine quaternary ammonium salt-haloamine precursor. Step B3: Melamine diborate is prepared using boric acid and melamine as raw materials. After the melamine diborate coats the nano copper powder, it is calcined to obtain modified copper powder. The modified copper powder is then processed to obtain aminated modified copper powder. Aminated modified copper powder and graphene oxide were assembled to obtain a multi-component composite powder; glutaraldehyde was used as a crosslinking agent to combine the multi-component composite powder with a Schiff base-pyridine quaternary ammonium salt-haloamine compound precursor to obtain an organic-inorganic composite material, which was then treated with sodium hypochlorite to obtain a chlorinated organic-inorganic composite material. Step (2): Blend cotton fiber and cool-feeling antibacterial regenerated fiber into yarn, knit to obtain the inner layer; immerse the inner layer in a protective liquid, and after immersion, pre-bake and bake to obtain the modified inner layer; Step (3): Blend modified polyester fiber and cool-feeling antibacterial regenerated fiber into yarn, knit to obtain the surface layer; immerse the surface layer in a hydrophobic finishing agent, and after immersion, pre-bake and bake to obtain the modified surface layer; The modified inner layer and modified outer layer are laminated, aligned, and combined to obtain an antibacterial and sun-protective composite fabric. The method for preparing the modified polyester fiber includes the following steps: Step A1: Wash freshly picked guava leaves with water, dry them in the sun, grind them to obtain guava leaf powder, mix the guava leaf powder with deionized water, boil at 90-95℃ for 4.5-5.5h, filter, heat at 65-75℃ to concentrate the filtrate to 5-10mL, then add manganese sulfate monohydrate and titanium dioxide nanoparticles, keep at 180-190℃ for 5-6h, filter, dry, and obtain double-doped carbon dots; wherein, the mass ratio of guava leaf powder, deionized water, manganese sulfate monohydrate, and titanium dioxide nanoparticles is (15-20):(60-80):(0.03-0.06):(0.05-0.08); The double-doped carbon dots, activated polyester fibers, p-toluenesulfonic acid, and cyclohexane were mixed in a mass ratio of (1-2):(10-15):(0.1-0.2):(150-200). The mixture was stirred and reacted at 120-140℃ for 3-5 hours under a nitrogen atmosphere. After the reaction was completed, the mixture was filtered, washed, and dried to obtain surface-modified polyester fibers. Step A2: Mix 3-aminopropyltriethoxysilane and ethanol at a ratio of (8-16) g:(20-50) mL, then add acetic acid to adjust the pH to 3.8-4.2 to obtain a mixture; add surface-modified polyester fibers to the above mixture at a solid-liquid ratio of 1:(15-25), immerse at 65-75℃ for 40-80 min, remove, wash, and dry to obtain amino-modified polyester fibers; Protocatechuic aldehyde was dissolved in deionized water to obtain a treatment solution with a concentration of 5-8 mg / mL. Amino-modified polyester fibers were added to the treatment solution at a solid-liquid ratio of 1:(10-20). The solution was stirred at 45-55℃ for 10-15 h, then removed and dried at 55-65℃ for 50-70 min. After washing, protocatechuic aldehyde-modified polyester fibers were obtained. The protocatechuic aldehyde-modified polyester fibers were then soaked in a 0.2 mol / L ferric chloride aqueous solution at 75-85℃ with a solid-liquid ratio of 1:(10-20) for 1-2 h. After soaking, the fibers were dried at 55-65℃ for 50-70 min, washed, and dried again to obtain modified polyester fibers.

2. The method for preparing the antibacterial and sun-protective composite fabric according to claim 1, characterized in that, In step (1), the preparation method of the cool-feeling antibacterial regenerated fiber is as follows: recycled flax fiber is mixed with 1-butyl-3-methylimidazolium acetate, and stirred at a speed of 500-600 r / min for 1.5-2.5 h in a constant temperature water bath at 75-85℃. Dimethyl sulfoxide is added, and stirring is continued for 2.5-3.5 h. Then, chlorinated organic-inorganic composite material is added, and stirring is carried out for 20-40 min. The mixture is defoamed at 35-45℃ for 10-15 h to obtain a spinning solution, which is then spun. The mass ratio of recycled flax fiber, 1-butyl-3-methylimidazolium acetate, dimethyl sulfoxide, and chlorinated organic-inorganic composite material in the spinning solution is 1:(18-22):(54-66):(0.5-0.7).

3. The method for preparing the antibacterial and sun-protective composite fabric according to claim 1, characterized in that, In step (1), the preparation method of the chlorinated organic-inorganic composite material is as follows: Step B1: Guanidine carbonate, α-acetyl-γ-butyrolactone, triethylamine, and ethanol are mixed in a mass ratio of (11.3-22.6):(2.4-4.8):(3.8-7.6):(23-46). The mixture is stirred at 28-32℃ for 40-80 min, then the temperature is raised to 75-85℃ and the reaction is stirred for 20-30 h to obtain a pale yellow suspension. The suspension is filtered, washed, and dried to obtain the intermediate product. The intermediate product is then added to tetrahydro-... Triethylamine was added to furan, and the mixture was stirred in an ice-water bath for 20-40 min. Acryloyl chloride was then added, and the mixture was stirred in an ice-water bath for 50-70 min, followed by stirring at room temperature for 20-24 h. The mixture was then filtered, washed, and vacuum dried to obtain the N-haloamine precursor. The mass ratio of the intermediate, tetrahydrofuran, triethylamine, and acryloyl chloride was (15-30):(150-250):(10.1-20.1):(9-18). Step B2: Add 4-aminobutane-1-thiol to ethanol, sonicate for 20-40 min, then add 4-pyridinecarboxaldehyde, stir and react at 50-60℃ for 8-12 h. After the reaction is complete, remove the solvent by vacuum distillation to obtain Schiff base-pyridine compound; wherein the mass ratio of 4-aminobutane-1-thiol, ethanol and 4-pyridinecarboxaldehyde is (10.5-21):(150-250):(10.7-21.4); The N-haloamine precursor was added to ethanol, sonicated for 20-40 min, heated to 50-80℃, and then azobisisobutyronitrile and Schiff base-pyridine compound were added. The mixture was stirred for 3-5 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain the Schiff base-pyridine-haloamine precursor. The mass ratio of the N-haloamine precursor, ethanol, azobisisobutyronitrile, and Schiff base-pyridine compound was (11.2-22.4):(150-200):(0.2-0.5):(9.7-19.4). Schiff base-pyridine-haloamine precursor and bromotetradecane were added to dimethyl sulfoxide at a mass ratio of (10.2-20.2):(10.4-17.3):(150-250) and reacted at 80-90℃ for 24-30 h. After the reaction was completed, the mixture was filtered, washed and dried to obtain Schiff base-pyridine quaternary ammonium salt-haloamine precursor. Step B3: Mix boric acid, melamine, and deionized water in a mass ratio of (1.9-3.8):(2.5-4.5):(200-300), heat to 100-110℃ and stir at 200-400 r / min for 7-9 h, cool naturally to room temperature, precipitate the crude product, filter, and dry to obtain melamine diborate. Nano copper powder, melamine diborate, and deionized water are mixed in a mass ratio of (2-4):(0.2-0.4):(200-300) and stirred at a speed of 150-250 r / min. The mixture is heated at 240-260℃ until the deionized water is completely evaporated to obtain melamine diborate-coated copper powder. The melamine diborate-coated copper powder is heated to 900-1100℃ and kept in an argon and hydrogen flow for 2.5-3.5 h to obtain modified copper powder. The argon flow rate is 200 sccm and the hydrogen flow rate is 10 sccm. Modified copper powder was ultrasonically mixed with 30wt% hydrogen peroxide aqueous solution at a mass ratio of 1:100 for 10-15 h, and reacted at 105-110℃ for 20-24 h. After the reaction was completed, hydroxylated modified copper powder was obtained. Hydroxylated modified copper powder, ethanol, and N-(2-aminoethyl)-3-aminopropyltrimethoxysilane were mixed at a mass ratio of (15-20):(50-60):(1.5-2.5), and stirred and reacted at 60-70℃ for 30-60 min in a light-protected environment and nitrogen atmosphere. After filtration, washing, and drying, amino-modified copper powder was obtained. Aminated modified copper powder and graphene oxide powder were ultrasonically dispersed in deionized water to obtain aminated modified copper powder dispersion and graphene oxide dispersion with concentrations of 2-5 mg / mL. The aminated modified copper powder dispersion was added dropwise to the graphene oxide dispersion at a rate of 1-2 mL / min, stirred at a speed of 400-600 r / min for 5-15 min, ultrasonically treated at a power of 150-250 W for 5-15 min, and then ultrasonically treated in an ice-water bath at a pH of 7-8 and an ultrasonic power of 50-70 W for 10-20 min. After centrifugation, the supernatant was removed, and the mixture was dried to obtain a multi-component composite powder. The multi-component composite powder was mixed with ethanol containing 5wt% glutaraldehyde at a ratio of (2-4)g:(30-60)mL and reacted at 95-105℃ for 8-12h. After filtration and washing, the modified multi-component composite powder was obtained. The Schiff base-pyridine quaternary ammonium salt-haloamine compound precursor, dimethyl sulfoxide, and the modified multi-component composite powder were mixed at a mass ratio of (5-10):(100-120):(3-5) and stirred at 45-55℃ for 10-16h. After filtration, washing, and drying, the organic-inorganic composite material was obtained. The organic-inorganic composite material was added to a 10wt% sodium hypochlorite aqueous solution at a solid-liquid ratio of 1:(25-35), and the pH was adjusted to 7 with acetic acid. The mixture was stirred at room temperature for 1.5-2.5 h, filtered, washed, and dried to obtain the chlorinated organic-inorganic composite material.

4. The method for preparing the antibacterial and sun-protective composite fabric according to claim 1, characterized in that, In step (2), the mass ratio of cotton fiber to cool-feeling antibacterial regenerated fiber is (60-70):(30-40), the English count of the blended yarn is 40-60S, and the weight of the inner layer is 80-100g / m². 2 The protective liquid is prepared by mixing polydimethylsiloxane, cyclohexane, and double-doped carbon dots in a mass ratio of (8-12):(88-92):(0.5-2).

5. The method for preparing the antibacterial and sun-protective composite fabric according to claim 1, characterized in that, In step (2), the impregnation conditions are: impregnation at room temperature for 20-30 minutes, one impregnation and one rolling, with a roll-off rate of 90-95% and a bath ratio of 1:(15-25).

6. The method for preparing the antibacterial and sun-protective composite fabric according to claim 1, characterized in that, In step (3), the mass ratio of the modified polyester fiber to the cool-feeling antibacterial regenerated fiber is (75-85):(15-25), and the English count of the blended yarn is 60-80S; the basis weight of the surface layer is 100-120g / m². 2 The hydrophobic finishing agent is obtained by mixing polydimethylsiloxane and isopropanol in a volume ratio of 10:

25.

7. The method for preparing the antibacterial and sun-protective composite fabric according to claim 1, characterized in that, In step (3), the impregnation conditions are: impregnation at room temperature for 20-30 minutes, one impregnation and one rolling, with a roll residue of 75-88% and a bath ratio of 1:(15-25).

8. The method for preparing the antibacterial and sun-protective composite fabric according to claim 1, characterized in that, In step A1, the method for preparing the activated polyester fiber is as follows: the polyester fiber is immersed in a sodium hydroxide aqueous solution with a concentration of 20 g / L, and after alkali immersion treatment at 90-100℃ for 20-40 min, it is transferred to a deionized water mixture of choline chloride and oxalic acid, and deep-treated at 40-80℃ for 0.5-2 h. After washing and drying, the activated polyester fiber is obtained. The mass ratio of choline chloride to oxalic acid in the deionized water mixture of choline chloride and oxalic acid is 3:2, the total concentration of choline chloride and oxalic acid is 50 g / L, and the bath ratio of alkali immersion treatment and deep treatment is (25-35):

1.

9. An antibacterial and sun-protective composite fabric prepared by the method of preparing antibacterial and sun-protective composite fabric as described in any one of claims 1-8.

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