Polyester fiber fabric preparation method

Abstract

The invention relates to the technical field of polyester fibers, and discloses a preparation method of a polyester fiber fabric. A waterproof antibacterial copolyester polymer with a structure similar to that of PET polyester is obtained through esterification condensation polymerization of raw materials such as N, N '-di-Boc-S-methyl isothiourea and dimethyl terephthalate, the structure of the waterproof antibacterial copolyester polymer contains quaternary ammonium salt, guanidyl and a hydrophobic long-chain structure, the waterproof antibacterial copolyester polymer can be uniformly distributed in a polyester fiber matrix, migration of antibacterial groups is avoided, and the antibacterial property of the polyester fiber is improved. The antibacterial performance on bacteria is better exerted; the C-F bond energy is high, fluorine atoms are more easily embedded into a polymer, a channel for water molecules to migrate into a coating film is blocked, a stable protection layer can be formed on the surface of the fiber fabric, fibers are wrapped, moisture is prevented from permeating into the fibers, and therefore the waterproof effect is achieved; meanwhile, the hydrophobic layer also has certain durability and does not lose efficacy after being washed with water for many times.

Description

[0001] This application is a divisional application of the application with the application number 2024114045976, the application date of October 10, 2024, and the invention name of "A Waterproof and Antibacterial Polyester Fiber Fabric and Its Preparation Method". Technical Field

[0002] The present invention relates to the technical field of polyester fibers, and specifically to a method for preparing a polyester fiber fabric. Background Art

[0003] Polyester, also known as polyethylene terephthalate (PET), is a polyester formed by the polycondensation of organic dibasic acids and diols and obtained by spinning. It has advantages such as good wrinkle resistance and shape retention, high strength, and strong elastic recovery ability, and is firm and durable, wrinkle-resistant and non-ironing. It can be spun alone or blended with other fibers, so it is widely used in the fields of clothing, home textiles, decoration, and industry; however, polyester fibers also have some inherent disadvantages, especially poor waterproof and antibacterial properties; the presence of sweat or moisture on polyester fibers provides suitable conditions for the growth of microorganisms, and the attachment of bacteria and other microorganisms will form a biofilm on the fabric that is difficult to remove, endangering human health; therefore, it is urgent to develop a polyester fiber fabric with both waterproof and antibacterial functions.

[0004] The chemical structure of polyester fibers is stable and not easily reactive with chemical reagents such as acids and bases. At the same time, the surface of polyester fibers is smooth and not easily adsorbent to antibacterial agents; currently, antibacterial agents applied to fiber products are divided into three categories: inorganic antibacterial agents represented by silver nanoparticles, although having excellent antibacterial effects, have deficiencies such as high price, weak adhesion, and poor durability, and some inorganic antibacterial agents will also pose safety hazards to the human body due to their own toxicity; natural antibacterial agents derived from cyclodextrin and chitosan have poor thermal stability, complicated processing processes, and are difficult to use and produce in large quantities for a long time; organic synthetic antibacterial agents mainly based on polyethyleneimine and alkylguanidine are restricted in their development in actual production applications due to poor heat resistance and complicated finishing processes.

[0005] Polyester fibers themselves do not have waterproof properties. The linear molecules in their molecular structure have no large branches, and the lack of hydrophilic groups results in poor moisture absorption properties of polyester fibers. Their swelling property in water is also poor. This structural feature determines that when polyester fibers encounter moisture, it is not easy to form an effective waterproof layer, thus being prone to water seepage. Patent No. CN118087074A discloses an antibacterial polyester fiber and its preparation method. By synthesizing quaternary ammonium salt-ester group polymer modified chitosan, the hydrophilicity of polyester fibers and their fabric materials can be effectively improved, the moisture regain rate is significantly increased, and it contains quaternary ammonium salt antibacterial groups, which are evenly distributed in the polyester fiber matrix, significantly improving the antibacterial properties of polyester fiber fabric materials against Escherichia coli and Staphylococcus aureus. However, it does not significantly improve the waterproof performance of the fiber fabric, and only contains a single quaternary ammonium salt antibacterial group, with limited antibacterial effect. The present invention aims to utilize the principle that fluorine atoms in organofluorine are easily embedded in polymers to block the channels for water molecules to migrate into the coating film. An organofluorine long chain, quaternary ammonium salt, and guanidine compound are introduced into a glycol structure, and esterification polycondensation is carried out with dimethyl terephthalate. After melt spinning, a polyester fiber fabric is obtained. By using the synergistic antibacterial effect of quaternary ammonium salt and guanidine, the prepared polyester fiber has both waterproof and antibacterial properties. Summary of the Invention

[0006] The purpose of the present invention is to solve the problems existing in the above-mentioned prior art, and to provide a waterproof and antibacterial polyester fiber fabric and its preparation method, preparing a polyester fiber fabric with good waterproof performance and excellent antibacterial performance, and broadening its application scope.

[0007] The present invention is achieved through the following technical solutions: A preparation method of a waterproof and antibacterial polyester fiber fabric includes the following steps: Step (1): Under a nitrogen atmosphere, add dimethyl terephthalate and a perfluoro intermediate of biguanol quaternary ammonium salt to a reaction flask, heat until the raw materials melt, add zinc acetate, heat to 210 - 225 °C for an ester exchange reaction for 3 - 6 h, add ethylene glycol antimonate, raise the temperature to 270 - 290 °C, reduce the pressure to 80 - 100 Pa and react for 1 - 3 h, cool to room temperature, and obtain a waterproof and antibacterial copolyester polymer after drying.

[0008] Step (2): Place the vacuum-dried PET polyester chips and the waterproof and antibacterial copolyester polymer in a twin-screw extruder for melt blending, extrude and pelletize, and then carry out melt spinning on a high-speed composite spinning machine. The spinning speed is 800 - 1200 m / min, the temperature of the spinning machine is 260 - 290 °C. After the nascent fibers are balanced, carry out stretching and winding forming on a parallel drawing machine to obtain a waterproof and antibacterial polyester fiber fabric.

[0009] Further, in step (1), the proportional relationship of dimethyl terephthalate, perfluoro intermediate of biguanol quaternary ammonium salt, zinc acetate, and antimony glycolate is 1 mol:(0.95 - 1.1) mol:(0.003 - 0.005) mol:(0.008 - 0.012) mol.

[0010] Further, in step (2), the proportional relationship of PET polyester chips and waterproof and antibacterial copolyester polymer is 100 g:(5 - 25) g.

[0011] Further, in step (2), the screw temperature of the twin-screw extruder is 240 - 260 °C, and the screw speed is set at 25 - 40 r / min; the temperature of the hot roller of the drawing machine is 80 - 90 °C, the drawing speed is 300 - 400 m / min, and the drawing ratio is 5.5 - 6.5.

[0012] Further, the preparation method of the perfluoro intermediate of biguanol quaternary ammonium salt in step (1) includes the following steps: Step S1: Under a nitrogen atmosphere, add N,N′-bis(2-hydroxyethyl)ethylenediamine and dichloromethane to a reaction flask. After stirring evenly, add N,N-diisopropylethylamine and N,N′-bis(2-hydroxyethyl)ethylenediamine, and stir to react. After the reaction is completed, concentrate under reduced pressure and purify by column chromatography to obtain the biguanol tertiary amine intermediate. The preparation reaction formula is as follows: Step S2: Under a nitrogen atmosphere, add the biguanol tertiary amine intermediate and N,N-dimethylformamide to a reaction flask. After stirring evenly, add perfluorodecylethyl iodide, and stir to react. After the reaction is completed, concentrate under reduced pressure and dry to obtain the perfluoro intermediate of biguanol quaternary ammonium salt. The preparation reaction formula is as follows: Further, in step S1, the proportional relationship of N,N′-bis(2-hydroxyethyl)ethylenediamine, N,N-diisopropylethylamine, and N,N'-di-Boc-S-methylisothiourea is 1 mol:(2.5 - 3.5) mol:(2.05 - 2.2) mol.

[0013] Further, in step S1, the reaction temperature is 20 - 35 °C, and the reaction time is 8 - 16 h.

[0014] Further, in step S2, the proportional relationship of the biguanol tertiary amine intermediate and perfluorodecylethyl iodide is 1 mol:(2.3 - 2.8) mol.

[0015] Further, in step S2, the reaction temperature is 110 - 130 °C, and the reaction time is 24 - 48 h.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: First, the present invention uses N,N′-bis(2-hydroxyethyl)ethylenediamine to react with N,N'-di-Boc-S-methylisothiourea under the action of N,N-diisopropylethylamine to obtain a biguanol tertiary amine intermediate. Then, it undergoes a quaternization reaction with perfluorodecylethyl iodide to obtain a perfluoro intermediate of biguanol quaternary salt. Next, it reacts with dimethyl terephthalate through esterification and polycondensation reactions to obtain a waterproof and antibacterial copolyester polymer. Finally, it is melt-spun with PET polyester chips to obtain a waterproof and antibacterial polyester fiber fabric.

[0017] The waterproof and antibacterial copolyester polymer contains quaternary ammonium salt, guanidine group and hydrophobic long-chain structure. Among them, the quaternary ammonium salt adsorbs to negatively charged bacteria through electrostatic force, hydrogen bond force, etc., aggregates on the cell wall, hinders the action of cell lysozyme, and destroys the cell surface structure, resulting in the basic function of the cell membrane being affected; the guanidine group can destroy the biological activity of phospholipids and the structure of the cell membrane, quickly adsorb to the negatively charged bacterial cell membrane, and undergo ion exchange with cations inside the cell membrane, resulting in an increase in the permeability of the cell membrane and the leakage of substances inside the cell; the hydrophobic long-chain is embedded on the surface of the bacteria, combines with the phospholipid bilayer in the cell membrane, produces a steric hindrance effect, and blocks the exchange of substances inside and outside the cell, ultimately killing the bacteria.

[0018] The waterproof and antibacterial copolyester polymer has a similar structure to PET polyester, and the two have good compatibility. The copolymer containing quaternary ammonium salt and guanidine antibacterial groups can be evenly distributed in the polyester fiber matrix, avoiding the migration of antibacterial groups and better exerting the antibacterial performance against bacteria; the C-F bond energy in the waterproof and antibacterial copolyester polymer is high. Compared with hydrogen atoms, fluorine atoms are more likely to be embedded in the polymer, blocking the channel for water molecules to migrate into the coating film, and a stable protective layer can be formed on the surface of the fiber fabric to wrap the fiber and prevent water from penetrating into the fiber interior, thereby playing a waterproof role; in addition, the alkyl long-chain provides a hydrophobic group, which can construct a uniform polymer network hydrophobic layer on the fiber surface, reduce the surface free energy of the fiber, limit the diffusion and penetration of water droplets on the fiber fabric; at the same time, this hydrophobic layer also has a certain durability and can withstand multiple washes without failure. Detailed embodiments

[0019] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention will be further described in detail below in combination with specific embodiments. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

[0020] Unless otherwise specified, the raw materials and reagents used in the present application are all commercially available products or can be prepared by known methods.

[0021] N,N′-bis(2-hydroxyethyl)ethylenediamine, CAS number: 4439-20-7.

[0022] N,N'-Di-Boc-S-methylisothiourea, with CAS number 107819-90-9.

[0023] Perfluorodecylethyl iodide, with CAS number 2043-54-1.

[0024] Example 1 (1) Under a nitrogen atmosphere, 85 mmol of N,N′-bis(2-hydroxyethyl)ethylenediamine and 680 mL of dichloromethane were added to a reaction flask. After stirring evenly, 255 mmol of N,N-diisopropylethylamine and 180.2 mmol of N,N'-di-Boc-S-methylisothiourea were added. The reaction was carried out at 25 °C for 12 h, concentrated under reduced pressure, and purified by column chromatography (the volume ratio of n-hexane to ethyl acetate was 2:1) to obtain the biguanol tertiary amine intermediate.

[0025] (2) Under a nitrogen atmosphere, 80 mmol of the biguanol tertiary amine intermediate and 1200 mL of N,N-dimethylformamide were added to a reaction flask. After stirring evenly, 200 mmol of perfluorodecylethyl iodide was added. The reaction was carried out at 120 °C for 32 h, concentrated under reduced pressure, and dried to obtain the biguanol quaternary ammonium salt perfluoro intermediate.

[0026] (3) Under a nitrogen atmosphere, 10 mmol of dimethyl terephthalate and 9.5 mol of the biguanol quaternary ammonium salt perfluoro intermediate were added to a reaction flask. The raw materials were heated until melted, 0.04 mmol of zinc acetate was added, and the transesterification reaction was carried out at 215 °C for 5 h. 0.09 mmol of antimony glycolate was added, the temperature was raised to 280 °C, and the pressure was reduced to 90 Pa for 2 h. After cooling to room temperature and drying, the waterproof and antibacterial copolyester polymer was obtained.

[0027] (4) 100 g of PET polyester chips after vacuum drying and 5 g of the waterproof and antibacterial copolyester polymer were placed in a twin-screw extruder for melt blending, and then pelletized. The screw temperature of the twin-screw extruder was 250 °C, and the screw speed was set at 30 r / min. Then, melt spinning was carried out on a high-speed composite spinning machine, the spinning speed was 1000 m / min, and the spinning machine temperature was 280 °C. After the nascent fiber was balanced, it was drawn and wound on a parallel drawing machine. The hot roll temperature of the drawing machine was 85 °C, the drawing speed was 350 m / min, and the drawing ratio was 6 to obtain the waterproof and antibacterial polyester fiber fabric.

[0028] Example 2 (1) Under a nitrogen atmosphere, 120 mmol of N,N′-bis(2-hydroxyethyl)ethylenediamine and 600 mL of dichloromethane were added to a reaction flask. After stirring evenly, 300 mmol of N,N-diisopropylethylamine and 246 mmol of N,N'-di-Boc-S-methylisothiourea were added, and the reaction was carried out at 35 °C for 8 h. Then, it was concentrated under reduced pressure and purified by column chromatography (the volume ratio of n-hexane to ethyl acetate was 2:1) to obtain the biguanol tertiary amine intermediate.

[0029] (2) Under a nitrogen atmosphere, 110 mmol of the biguanol tertiary amine intermediate and 1320 mL of N,N-dimethylformamide were added to a reaction flask. After stirring evenly, 253 mmol of perfluorodecylethyl iodide was added, and the reaction was carried out at 130 °C for 24 h. Then, it was concentrated under reduced pressure and dried to obtain the perfluoro intermediate of biguanol quaternary ammonium salt.

[0030] (3) Under a nitrogen atmosphere, 10 mmol of dimethyl terephthalate and 10 mol of the perfluoro intermediate of biguanol quaternary ammonium salt were added to a reaction flask. It was heated until the raw materials melted, 0.03 mmol of zinc acetate was added, and the transesterification reaction was carried out at 225 °C for 3 h. Then, 0.08 mmol of antimony glycolate was added, the temperature was raised to 270 °C, and the reaction was carried out under a reduced pressure of 100 Pa for 1 h. After cooling to room temperature and drying, the waterproof and antibacterial copolyester polymer was obtained.

[0031] (4) 100 g of PET polyester chips after vacuum drying and 10 g of the waterproof and antibacterial copolyester polymer were placed in a twin-screw extruder for melt blending, and then pelletized. The screw temperature of the twin-screw extruder was 260 °C, and the screw speed was set at 40 r / min. Then, melt spinning was carried out on a high-speed composite spinning machine, the spinning speed was 1200 m / min, and the temperature of the spinning machine was 290 °C. After the nascent fiber was balanced, it was drawn and wound on a parallel drawing machine. The temperature of the hot roller of the drawing machine was 90 °C, the drawing speed was 400 m / min, and the drawing ratio was 6.5 to obtain the waterproof and antibacterial polyester fiber fabric.

[0032] Example 3 (1) Under a nitrogen atmosphere, 60 mmol of N,N′-bis(2-hydroxyethyl)ethylenediamine and 600 mL of dichloromethane were added to a reaction flask. After stirring evenly, 210 mmol of N,N-diisopropylethylamine and 132 mmol of N,N'-di-Boc-S-methylisothiourea were added, and the reaction was carried out at 20 °C for 16 h. Then, it was concentrated under reduced pressure and purified by column chromatography (the volume ratio of n-hexane to ethyl acetate was 2:1) to obtain the biguanol tertiary amine intermediate.

[0033] (2) Under a nitrogen atmosphere, 50 mmol of the biguanol tertiary amine intermediate and 1000 mL of N,N-dimethylformamide were added to the reaction flask. After stirring evenly, 140 mmol of perfluorodecylethyl iodide was added, and the reaction was carried out at 110 °C for 48 h. After concentration under reduced pressure and drying, the perfluoro intermediate of the biguanol quaternary ammonium salt was obtained.

[0034] (3) Under a nitrogen atmosphere, 40 mmol of dimethyl terephthalate and 42 mol of the perfluoro intermediate of the biguanol quaternary ammonium salt were added to the reaction flask. After heating until the raw materials melted, 0.2 mmol of zinc acetate was added, and the transesterification reaction was carried out at 210 °C for 6 h. Then 0.48 mmol of ethylene glycol antimony was added, the temperature was raised to 270 °C, and the pressure was reduced to 8 Pa for 3 h. After cooling to room temperature and drying, the waterproof and antibacterial copolyester polymer was obtained.

[0035] (4) 100 g of PET polyester chips after vacuum drying and 15 g of the waterproof and antibacterial copolyester polymer were placed in a twin-screw extruder for melt blending, and then pelletized. The screw temperature of the twin-screw extruder was 240 °C, and the screw speed was set at 25 r / min. Then melt spinning was carried out on a high-speed composite spinning machine, the spinning speed was 800 m / min, and the spinning machine temperature was 260 °C. After the nascent fibers were balanced, drawing and winding were carried out on a parallel drawing machine. The hot roller temperature of the drawing machine was 80 °C, the drawing speed was 300 m / min, and the drawing ratio was 5.5, obtaining the waterproof and antibacterial polyester fiber fabric.

[0036] Example 4 (1) Under a nitrogen atmosphere, 35 mmol of N,N′-bis(2-hydroxyethyl)ethylenediamine and 220 mL of dichloromethane were added to the reaction flask. After stirring evenly, 110 mmol of N,N-diisopropylethylamine and 76.3 mmol of N,N'-di-Boc-S-methylisothiourea were added, and the reaction was carried out at 30 °C for 15 h. After concentration under reduced pressure and purification by column chromatography (the volume ratio of n-hexane to ethyl acetate was 2:1), the biguanol tertiary amine intermediate was obtained.

[0037] (2) Under a nitrogen atmosphere, 28 mmol of the biguanol tertiary amine intermediate and 460 mL of N,N-dimethylformamide were added to the reaction flask. After stirring evenly, 74.2 mmol of perfluorodecylethyl iodide was added, and the reaction was carried out at 125 °C for 32 h. After concentration under reduced pressure and drying, the perfluoro intermediate of the biguanol quaternary ammonium salt was obtained.

[0038] (3) Under a nitrogen atmosphere, 10 mmol of dimethyl terephthalate and 10.8 mol of perfluorinated intermediate of bisguanidyl alcohol quaternary ammonium salt were added to a reaction flask. After heating until the raw materials melted, 0.035 mmol of zinc acetate was added. The mixture was heated to 215 °C for 4 h for transesterification reaction. Then 0.1 mmol of antimony glycolate was added, the temperature was raised to 275 °C, the pressure was reduced to 95 Pa, and the reaction was carried out for 3 h. After cooling to room temperature and drying, a waterproof and antibacterial copolyester polymer was obtained.

[0039] (4) 100 g of PET polyester chips after vacuum drying and 20 g of waterproof and antibacterial copolyester polymer were placed in a twin-screw extruder for melt blending, and then pelletized. The screw temperature of the twin-screw extruder was 245 °C, and the screw speed was set at 35 r / min. Then melt spinning was carried out on a high-speed composite spinning machine, the spinning speed was 1100 m / min, and the temperature of the spinning machine was 280 °C. After the as-spun fibers were balanced, drawing and winding were carried out on a parallel drawing machine. The temperature of the hot roller of the drawing machine was 90 °C, the drawing speed was 360 m / min, and the drawing ratio was 5.8, obtaining a waterproof and antibacterial polyester fiber fabric.

[0040] Example 5 (1) Under a nitrogen atmosphere, 25 mmol of N,N′-bis(2-hydroxyethyl)ethylenediamine and 200 mL of dichloromethane were added to a reaction flask. After stirring evenly, 80 mmol of N,N-diisopropylethylamine and 54 mmol of N,N'-di-Boc-S-methylisothiourea were added, and the reaction was carried out at 35 °C for 12 h. After concentration under reduced pressure, purification by column chromatography (the volume ratio of n-hexane to ethyl acetate was 2:1) was carried out to obtain the bisguanidyl alcohol tertiary amine intermediate.

[0041] (2) Under a nitrogen atmosphere, 20 mmol of bisguanidyl alcohol tertiary amine intermediate and 350 mL of N,N-dimethylformamide were added to a reaction flask. After stirring evenly, 56 mmol of perfluorodecylethyl iodide was added, and the reaction was carried out at 125 °C for 48 h. After concentration under reduced pressure and drying, the perfluorinated intermediate of bisguanidyl alcohol quaternary ammonium salt was obtained.

[0042] (3) Under a nitrogen atmosphere, 10 mmol of dimethyl terephthalate and 11 mol of perfluorinated intermediate of bisguanidyl alcohol quaternary ammonium salt were added to a reaction flask. After heating until the raw materials melted, 0.05 mmol of zinc acetate was added. The mixture was heated to 220 °C for 6 h for transesterification reaction. Then 0.11 mmol of antimony glycolate was added, the temperature was raised to 280 °C, the pressure was reduced to 100 Pa, and the reaction was carried out for 2 h. After cooling to room temperature and drying, a waterproof and antibacterial copolyester polymer was obtained.

[0043] (4) 100 g of PET polyester chips after vacuum drying and 25 g of the waterproof and antibacterial copolyester polymer were placed in a twin-screw extruder for melt blending and pelletizing. The screw temperature of the twin-screw extruder was 255 °C, and the screw speed was set at 30 r / min. Then, melt spinning was carried out on a high-speed composite spinning machine at a spinning speed of 950 m / min and a spinning machine temperature of 275 °C. After the as-spun fibers were balanced, drawing and winding were carried out on a parallel drawing machine. The hot roller temperature of the drawing machine was 90 °C, the drawing speed was 350 m / min, and the draw ratio was 6, obtaining a waterproof and antibacterial polyester fiber fabric.

[0044] Comparative Example 1 (1) Under a nitrogen atmosphere, 10 mmol of dimethyl terephthalate and 9.5 mol of the biguanol tertiary amine intermediate (prepared in Example 1) were added to a reaction flask. The mixture was heated until the raw materials melted, 0.04 mmol of zinc acetate was added, and the transesterification reaction was carried out at 215 °C for 5 h. Then, 0.09 mmol of ethylene glycol antimony was added, the temperature was raised to 280 °C, and the pressure was reduced to 90 Pa for 2 h. After cooling to room temperature and drying, the copolyester polymer was obtained.

[0045] (2) 100 g of PET polyester chips after vacuum drying and 5 g of the copolyester polymer were placed in a twin-screw extruder for melt blending and pelletizing. The screw temperature of the twin-screw extruder was 250 °C, and the screw speed was set at 30 r / min. Then, melt spinning was carried out on a high-speed composite spinning machine at a spinning speed of 1000 m / min and a spinning machine temperature of 280 °C. After the as-spun fibers were balanced, drawing and winding were carried out on a parallel drawing machine. The hot roller temperature of the drawing machine was 85 °C, the drawing speed was 350 m / min, and the draw ratio was 6, obtaining a polyester fiber fabric.

[0046] Comparative Example 2 (1) Under a nitrogen atmosphere, 10 mmol of dimethyl terephthalate and 9.5 mol of N,N′-bis(2-hydroxyethyl)ethylenediamine were added to a reaction flask. The mixture was heated until the raw materials melted, 0.04 mmol of zinc acetate was added, and the transesterification reaction was carried out at 215 °C for 5 h. Then, 0.09 mmol of ethylene glycol antimony was added, the temperature was raised to 280 °C, and the pressure was reduced to 90 Pa for 2 h. After cooling to room temperature and drying, the copolyester polymer was obtained.

[0047] (2) 100 g of PET polyester chips after vacuum drying and 5 g of copolyester polymer were placed in a twin-screw extruder for melt blending, and then pelletized. The screw temperature of the twin-screw extruder was 250 °C, and the screw speed was set at 30 r / min. Then, melt spinning was carried out on a high-speed composite spinning machine at a spinning speed of 1000 m / min and a spinning machine temperature of 280 °C. After the nascent fibers were balanced, drawing and winding were carried out on a parallel drawing machine. The hot roller temperature of the drawing machine was 85 °C, the drawing speed was 350 m / min, and the drawing ratio was 6, obtaining a polyester fiber fabric.

[0048] Antibacterial performance test: The test was carried out with reference to the standard GB / T 20944.3-2008 "Evaluation of Antibacterial Properties of Textiles - Part 3: Oscillation Flask Method". The antibacterial rates of the polyester fiber fabrics prepared in the examples and comparative examples against Escherichia coli and Staphylococcus aureus were tested respectively.

[0049] Table 1 Antibacterial Rate Test It can be seen from the test results in the above table that with the increase in the content of the waterproof and antibacterial copolyester polymer, the antibacterial performance of the polyester fiber fabric gradually increases. Among them, in Example 4, the antibacterial rate against Escherichia coli reached 99.9%, and the antibacterial rate against Staphylococcus aureus reached 98.2%. This is because on the one hand, the waterproof and antibacterial copolyester polymer contains quaternary ammonium salts, guanidine groups and hydrophobic long-chain structures. Among them, the quaternary ammonium salts are adsorbed to the negatively charged bacteria through electrostatic force, hydrogen bond force, etc., and accumulate on the cell wall, hindering the action of cell lysozyme, and the cell surface structure is damaged, resulting in the basic function of the cell membrane being affected; the guanidine group can destroy the biological activity of phospholipids and the structure of the cell membrane, quickly adsorb to the negatively charged bacterial cell membrane, and carry out ion exchange with the cations inside the cell membrane, resulting in an increase in the permeability of the cell membrane and the leakage of substances inside the cell; the hydrophobic long-chain is embedded on the surface of the bacteria and combines with the phospholipid bilayer in the cell membrane, producing a steric hindrance effect, and the exchange of substances inside and outside the cell is blocked, ultimately killing the bacteria. In Comparative Example 1, only the guanidine antibacterial group is contained, and the antibacterial effect is limited; in Comparative Example 2, no antibacterial group is contained, and it has no antibacterial effect.

[0050] Antibacterial durability test: The prepared polyester fiber fabric was cut into a size of 5 cm × 5 cm, placed in a beaker with a diameter of 50 cm, washed with 50 mL of a 2% sodium dodecyl sulfate aqueous solution, stirred at 300 rpm and 25 °C, with each 10 minutes as a washing cycle, and then washed with deionized water. After drying, the washed samples were subjected to an antibacterial durability test with reference to the standard GB / T20944.3-2008 "Evaluation of Antibacterial Properties of Textiles - Part 3: Oscillation Flask Method".

[0051] Table 2 Antibacterial Durability Test As can be seen from the test results in the above table, with the increase in the content of the waterproof and antibacterial copolyester polymer, the antibacterial durability of the polyester fiber fabric gradually increases. After 50 washes, the polyester fiber fabric still has a high antibacterial rate against Escherichia coli and Staphylococcus aureus. This is because the waterproof and antibacterial copolyester polymer has a similar structure to PET polyester, and the two have good compatibility. The copolymer containing quaternary ammonium salt and guanidine antibacterial groups can be evenly distributed in the polyester fiber matrix, avoiding the migration of antibacterial groups and better exerting the antibacterial performance against bacteria.

[0052] Water absorption rate test: Cut the prepared polyester fiber fabric into a size of 5 cm × 5 cm, put it into a beaker with a diameter of 200 cm filled with deionized water, calculate the weight difference after completely soaking for 30 min to calculate the water absorption rate, and measure it 3 times and take the average value. The water absorption rate = (W2 - W1) / W1 × 100%, where W1 and W2 are the weights of the fiber fabric before and after soaking, respectively.

[0053] Contact angle test: Use a contact angle tester to measure the water contact angle of the fiber fabric with deionized water (3 μL) at 25 °C and standard atmospheric pressure, and measure it 3 times and take the average value.

[0054] Table 3 Waterproof performance test Water absorption rate (%) Contact angle (°) Example 1 8.29 112.2 Example 2 5.01 125.3 Example 3 3.87 139.4 Example 4 1.32 153.0 Example 5 0.16 155.1 Comparative Example 1 15.32 80.7 Comparative Example 2 16.55 78.4 As can be seen from the test results in the above table, with the increase in the content of the waterproof and antibacterial copolyester polymer, the waterproof performance of the polyester fiber fabric gradually increases. This is because the waterproof and antibacterial copolyester polymer contains organic fluorine, and the C-F bond energy is high. Compared with hydrogen atoms, fluorine atoms are more likely to be embedded in the polymer, blocking the channels for water molecules to migrate into the coating film. A stable protective layer can be formed on the surface of the fiber fabric to wrap the fibers and prevent water from penetrating into the fiber interior, thus playing a waterproof role. In addition, the alkyl long chain provides hydrophobic groups, which can construct a uniform polymer network hydrophobic layer on the fiber surface, reduce the surface free energy of the fiber, and limit the diffusion and penetration of water droplets on the fiber fabric. At the same time, this hydrophobic layer also has a certain durability and can withstand multiple washes without failure.

[0055] The above are only the preferred embodiments of the present invention and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to the above-disclosed technical content to be equivalent embodiments with equivalent changes within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A method for preparing a polyester fiber fabric, characterized in that: The preparation method comprises the following steps: Step (1), under a nitrogen atmosphere, add dimethyl terephthalate and biguanide quaternary ammonium salt perfluoro intermediate into a reaction flask, heat until the raw materials melt, add zinc acetate, heat to 210-225° C. to carry out ester exchange reaction for 3-6 hours, add ethylene glycol antimony, heat to 270-290° C., reduce the pressure to 80-100 Pa, react for 1-3 hours, cool to room temperature, and dry to obtain a waterproof and antibacterial copolyester polymer; In the step (1), the ratio of dimethyl terephthalate, biguanide quaternary ammonium salt perfluoro intermediate, zinc acetate, and ethylene glycol antimony is 1 mol: (0.95-1.1) mol: (0.003-0.005) mol: (0.008-0.012) mol; Step (2), placing the vacuum-dried PET polyester chips and the waterproof and antibacterial copolyester polymer in a twin-screw extruder for melt blending, extrusion granulation, and then melt spinning on a high-speed composite spinning machine, and then drawing and winding to obtain a waterproof and antibacterial polyester fiber fabric; The method for preparing the biguanide quaternary ammonium salt perfluoro intermediate in step (1) comprises the following steps: Step S1, under a nitrogen atmosphere, add N,N′-bis(2-hydroxyethyl)ethylenediamine and dichloromethane to a reaction flask, stir evenly, then add N,N-diisopropylethylamine and N,N′-di-Boc-S-methylisothiourea, stir to react, and after the reaction is completed, concentrate under reduced pressure, and purify by column chromatography to obtain a biguanide alcohol tertiary amine intermediate; Step S2: under nitrogen atmosphere, add the biguanide alcohol tertiary amine intermediate and N,N-dimethylformamide into a reaction flask, stir evenly, add perfluorodecylethyl iodide, stir to react, after the reaction is completed, concentrate under reduced pressure, and dry to obtain the biguanide alcohol quaternary ammonium salt perfluoro intermediate.

2. The method for preparing the polyester fiber fabric according to claim 1, characterized in that: In the step (2), the spinning speed is 800-1200 m / min, the spinning machine temperature is 260-290° C., and after the primary fibers are balanced, they are stretched and wound on a parallel stretching machine; the ratio of PET polyester chips to waterproof and antibacterial copolyester polymer is 100 g: (5-25) g; the screw temperature of the twin-screw extruder is 240-260° C., and the screw speed is set to 25-40 r / min; the hot roller temperature of the stretching machine is 80-90° C., the stretching speed is 300-400 m / min, and the stretching multiple is 5.5-6.

5.

3. The method for preparing the polyester fiber fabric according to claim 2, characterized in that: In the step S1, the ratio of N,N′-bis(2-hydroxyethyl)ethylenediamine, N,N-diisopropylethylamine, and N,N′-di-Boc-S-methylisothiourea is 1 mol: (2.5-3.5) mol: (2.05-2.2) mol.

4. The method for preparing the polyester fiber fabric according to claim 3, characterized in that: In step S1, the reaction temperature is 20-35° C. and the reaction time is 8-16 h.

5. The method for preparing the polyester fiber fabric according to claim 4, characterized in that: In the step S2, the ratio of the biguanidine alcohol tertiary amine intermediate to perfluorodecylethyl iodide is 1 mol: (2.3-2.8) mol, the reaction temperature is 110-130° C., and the reaction time is 24-48 h.

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