A waterproof and antibacterial polyester fiber fabric and preparation method thereof

Abstract

The invention relates to the technical field of polyester fibers, and discloses a waterproof and antibacterial polyester fiber fabric and a preparation method thereof. N,N'-bis(2-hydroxyethyl)ethylenediamine, N,N'-di-Boc-S-methylisothiourea and the like are used as raw materials, and the raw materials are subjected to an esterification polycondensation reaction with dimethyl terephthalate to obtain a waterproof and antibacterial copolyester polymer having a structure similar to that of PET polyester. The waterproof and antibacterial copolyester polymer contains a quaternary ammonium salt, a guanidine group and a hydrophobic long chain structure, which can be evenly distributed in a polyester fiber matrix, thereby avoiding the migration of antibacterial groups and better exerting the antibacterial performance against bacteria. The C-F bond energy is high, and fluorine atoms are more easily embedded in the polymer, blocking the channel for water molecules to migrate into the inside of 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 inside of the fiber, thereby playing a waterproof role. At the same time, the hydrophobic layer also has certain durability and can withstand multiple washings without failure.

Description

Technical Field

[0001] The invention relates to the technical field of polyester fibers, in particular to a waterproof and antibacterial polyester fiber fabric and a preparation method thereof. Background Art

[0002] Polyester, also known as polyester (PET, polyethylene terephthalate) fiber, is obtained by spinning polyester formed by the condensation of organic dibasic acids and diols. It has the advantages of good wrinkle resistance and shape retention, high strength, strong elastic recovery ability, etc., and is durable, wrinkle-resistant and iron-free. It can be spun purely or blended with other fibers. Therefore, it is widely used in clothing, home textiles, decoration and industry. However, polyester fibers also have some inherent disadvantages, especially in terms of waterproof and antibacterial properties. Sweat or humidity on polyester fibers provide suitable conditions for the growth of microorganisms, and the attachment of bacteria and other microorganisms will form difficult-to-remove biofilms on the fabric, which is harmful to human health. Therefore, it is urgent to develop polyester fiber fabrics with both waterproof and antibacterial functions.

[0003] The chemical structure of polyester fiber is stable and it is not easy to react with chemical reagents such as acids and alkalis. At the same time, the surface of polyester fiber is smooth and it is not easy to adsorb antibacterial agents. The antibacterial agents currently used in fiber products are divided into three categories: although inorganic antibacterial agents represented by silver nanoparticles have excellent antibacterial effects, they are expensive, have weak adhesion, and poor durability. Some inorganic antibacterial agents may 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, cumbersome processing, and are difficult to use for a long time and mass produce; organic synthetic antibacterial agents based on polyethyleneimine and alkylguanidine have poor heat resistance and complex finishing processes, which limit their development in actual production applications.

[0004] Polyester fiber itself does not have waterproof properties. The linear molecules and lack of large side chains in its molecular structure, as well as the lack of hydrophilic groups, make the moisture absorption performance of polyester fiber poor and its swelling performance in water poor. This structural feature determines that when polyester fiber encounters moisture, it is not easy to form an effective waterproof layer, and it is easy to seep water. Patent No. CN118087074A discloses an antibacterial polyester fiber and a preparation method thereof. By synthesizing quaternary ammonium salt-ester polymer modified chitosan, the hydrophilicity of polyester fiber and its fabric can be effectively improved, the moisture regain rate is significantly improved, and it contains quaternary ammonium salt antibacterial groups, which are evenly distributed in In the polyester fiber matrix, the antibacterial performance of the polyester fiber fabric against Escherichia coli and Staphylococcus aureus is significantly improved, but the waterproof performance of the fiber fabric is not significantly improved, and only a single quaternary ammonium salt antibacterial group is contained, and the antibacterial effect is limited; the present invention aims to utilize the principle that fluorine atoms in organic fluorine are easily embedded in polymers and block the channels for water molecules to migrate into the coating film, introduce organic fluorine long chains, quaternary ammonium salts and guanidine compounds into the diol structure, and esterify and condense with dimethyl terephthalate, and obtain polyester fiber fabric after melt spinning, and utilize quaternary ammonium salts and guanidine groups for synergistic antibacterial effect, so that the prepared polyester fiber has both waterproof and antibacterial properties. Summary of the invention

[0005] 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 a preparation method thereof, so as to prepare a polyester fiber fabric with good waterproof and antibacterial properties, thereby broadening its application range.

[0006] The present invention is achieved through the following technical solutions:

[0007] A method for preparing a waterproof and antibacterial polyester fiber fabric comprises the following steps:

[0008] 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.

[0009] 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, the spinning speed is 800-1200m / min, the spinning machine temperature is 260-290°C, after the primary fibers are balanced, drawing and winding are performed on a parallel drawing machine to obtain a waterproof and antibacterial polyester fiber fabric.

[0010] Furthermore, in 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.

[0011] Furthermore, in step (2), the ratio of PET polyester chips to waterproof and antibacterial copolyester polymer is 100 g: (5-25) g.

[0012] Furthermore, in step (2), 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 drawing machine is 80-90°C, the drawing speed is 300-400 m / min, and the drawing multiple is 5.5-6.5.

[0013] Furthermore, the method for preparing the biguanide quaternary ammonium salt perfluoro intermediate in step (1) comprises the following steps:

[0014] Step S1: In a nitrogen atmosphere, N, N'-bis (2-hydroxyethyl) ethylenediamine and dichloromethane are added to a reaction flask, and after stirring, N, N'-diisopropylethylamine and N, N'-bis (2-hydroxyethyl) ethylenediamine are added, and the mixture is stirred for reaction. After the reaction is completed, the mixture is concentrated under reduced pressure and purified by column chromatography to obtain a biguanidine tertiary amine intermediate. The preparation reaction formula is as follows:

[0015]

[0016] Step S2: under nitrogen atmosphere, add biguanide alcohol tertiary amine intermediate and N,N-dimethylformamide to the reaction flask, stir evenly, add perfluorodecylethyl iodide, stir to react, after the reaction is completed, reduce pressure and concentrate, dry to obtain biguanide alcohol quaternary ammonium salt perfluoro intermediate. The preparation reaction formula is as follows:

[0017]

[0018] Furthermore, in 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.

[0019] Furthermore, in step S1, the reaction temperature is 20-35° C., and the reaction time is 8-16 h.

[0020] Furthermore, in step S2, the ratio of the biguanidine alcohol tertiary amine intermediate to perfluorodecylethyl iodide is 1 mol: (2.3-2.8) mol.

[0021] Furthermore, in step S2, the reaction temperature is 110-130° C., and the reaction time is 24-48 h.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The invention firstly utilizes N,N′-bis(2-hydroxyethyl)ethylenediamine and N,N′-di-Boc-S-methylisothiourea to react under the action of N,N-diisopropylethylamine to obtain a biguanidine alcohol tertiary amine intermediate, then undergoes a quaternization reaction with perfluorodecylethyl iodide to obtain a biguanidine alcohol quaternary ammonium salt perfluoro intermediate, then undergoes an esterification and polycondensation reaction with dimethyl terephthalate to obtain a waterproof and antibacterial copolyester polymer, and finally undergoes melt spinning with PET polyester chips to obtain a waterproof and antibacterial polyester fiber fabric.

[0024] The waterproof and antibacterial copolyester polymer contains quaternary ammonium salt, guanidine group and hydrophobic long chain structure. The quaternary ammonium salt is adsorbed to the negatively charged bacteria through electrostatic force, hydrogen bond force and the like, and aggregates on the cell wall, thereby hindering the action of cell lysozyme and destroying the cell surface structure, which affects the basic functions of the cell membrane. The guanidine group can destroy the biological activity of phospholipids and the structure of the cell membrane, and quickly adsorbs to the negatively charged bacterial cell membrane, and exchanges ions with the cations in the cell membrane, resulting in increased permeability of the cell membrane and leakage of substances in the cell. The hydrophobic long chain is embedded in the bacterial surface and combines with the phospholipid bilayer in the cell membrane, producing a chamber resistance effect, which hinders the exchange of substances inside and outside the cell and ultimately kills the bacteria.

[0025] The waterproof and antibacterial copolyester polymer has a similar structure to PET polyester, and the two have good compatibility. The copolymer containing quaternary ammonium salts and guanidine antibacterial groups can be evenly distributed in the polyester fiber matrix to avoid the migration of antibacterial groups and better exert the antibacterial performance against bacteria; the CF bond energy in the waterproof and antibacterial copolyester polymer is high. Compared with hydrogen atoms, fluorine atoms are more easily embedded in the polymer, blocking the channels for water molecules to migrate into the coating, and can form a stable protective layer on the surface of the fiber fabric to wrap the fiber and prevent water from penetrating into the fiber, thereby playing a waterproof role; in addition, the long alkyl 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, 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 washings without failure. DETAILED DESCRIPTION

[0026] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0027] Unless otherwise specified, the raw materials and reagents used in this application are commercially available or can be prepared by known methods.

[0028] N,N′-bis(2-hydroxyethyl)ethylenediamine, CAS number is 4439-20-7.

[0029] N,N'-Di-Boc-S-methylisothiourea, CAS number is 107819-90-9.

[0030] Perfluorodecylethyl iodide, CAS number is 2043-54-1.

[0031] Example 1

[0032] (1) Under nitrogen atmosphere, 85 mmol of N,N′-bis(2-hydroxyethyl)ethylenediamine and 680 mL of dichloromethane were added to a reaction flask. After stirring, 255 mmol of N,N-diisopropylethylamine and 180.2 mmol of N,N′-di-Boc-S-methylisothiourea were added. The mixture was reacted 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 a biguanide alcohol tertiary amine intermediate.

[0033] (2) Under nitrogen atmosphere, add 80 mmol of biguanide tertiary amine intermediate and 1200 mL of N,N-dimethylformamide into a reaction flask, stir evenly, add 200 mmol of perfluorodecylethyl iodide, react at 120 °C for 32 h, concentrate under reduced pressure, and dry to obtain the biguanide quaternary ammonium salt perfluoro intermediate.

[0034] (3) Under nitrogen atmosphere, 10 mmol of dimethyl terephthalate and 9.5 mol of biguanide quaternary ammonium salt perfluoro intermediate were added to the reaction flask, and the mixture was heated until the raw materials melted. 0.04 mmol of zinc acetate was added, and the mixture was heated to 215°C for ester exchange reaction for 5 h. 0.09 mmol of ethylene glycol antimony was added, and the mixture was heated to 280°C and reduced in pressure to 90 Pa for reaction for 2 h. The mixture was cooled to room temperature and dried to obtain a waterproof and antibacterial copolyester polymer.

[0035] (4) 100 g of vacuum-dried PET polyester chips and 5 g of waterproof and antibacterial copolyester polymer were placed in a twin-screw extruder for melt blending and extrusion granulation. The screw temperature of the twin-screw extruder was 250°C and the screw speed was set to 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, they were stretched and wound on a parallel stretching machine. The hot roller temperature of the stretching machine was 85°C, the stretching speed was 350 m / min, and the stretching multiple was 6 to obtain a waterproof and antibacterial polyester fiber fabric.

[0036] Example 2

[0037] (1) Under nitrogen atmosphere, 120 mmol of N,N′-bis(2-hydroxyethyl)ethylenediamine and 600 mL of dichloromethane were added to a reaction flask. After stirring, 300 mmol of N,N-diisopropylethylamine and 246 mmol of N,N′-di-Boc-S-methylisothiourea were added. The mixture was reacted at 35°C for 8 h, concentrated under reduced pressure, and purified by column chromatography (the volume ratio of n-hexane to ethyl acetate was 2:1) to obtain a biguanide alcohol tertiary amine intermediate.

[0038] (2) Under nitrogen atmosphere, 110 mmol of the biguanide alcohol tertiary amine intermediate and 1320 mL of N,N-dimethylformamide were added to a reaction flask. After stirring, 253 mmol of perfluorodecylethyl iodide was added. The mixture was reacted at 130 °C for 24 h. The mixture was concentrated under reduced pressure and dried to obtain the biguanide alcohol quaternary ammonium salt perfluoro intermediate.

[0039] (3) Under nitrogen atmosphere, 10 mmol of dimethyl terephthalate and 10 mol of biguanide quaternary ammonium salt perfluoro intermediate were added to the reaction flask, and the mixture was heated until the raw materials melted. 0.03 mmol of zinc acetate was added, and the mixture was heated to 225°C for ester exchange reaction for 3 h. 0.08 mmol of ethylene glycol antimony was added, and the mixture was heated to 270°C and reduced in pressure to 100 Pa for reaction for 1 h. The mixture was cooled to room temperature and dried to obtain a waterproof and antibacterial copolyester polymer.

[0040] (4) 100 g of vacuum-dried PET polyester chips and 10 g of waterproof and antibacterial copolyester polymer were placed in a twin-screw extruder for melt blending and extrusion granulation. The screw temperature of the twin-screw extruder was 260°C and the screw speed was set to 40 r / min. Then, melt spinning was carried out on a high-speed composite spinning machine at a spinning speed of 1200 m / min and a spinning machine temperature of 290°C. After the nascent fibers were balanced, they were stretched and wound on a parallel stretching machine. The hot roller temperature of the stretching machine was 90°C, the stretching speed was 400 m / min, and the stretching multiple was 6.5 to obtain a waterproof and antibacterial polyester fiber fabric.

[0041] Example 3

[0042] (1) Under nitrogen atmosphere, 60 mmol of N,N′-bis(2-hydroxyethyl)ethylenediamine and 600 mL of dichloromethane were added to a reaction flask. After stirring, 210 mmol of N,N-diisopropylethylamine and 132 mmol of N,N′-di-Boc-S-methylisothiourea were added. The mixture was reacted at 20°C for 16 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 biguanide alcohol tertiary amine intermediate.

[0043] (2) Under nitrogen atmosphere, 50 mmol of the biguanide tertiary amine intermediate and 1000 mL of N,N-dimethylformamide were added to a reaction flask. After stirring evenly, 140 mmol of perfluorodecylethyl iodide was added. The mixture was reacted at 110 °C for 48 h. The mixture was concentrated under reduced pressure and dried to obtain the biguanide quaternary ammonium salt perfluoro intermediate.

[0044] (3) Under nitrogen atmosphere, 40 mmol of dimethyl terephthalate and 42 mol of biguanide quaternary ammonium salt perfluoro intermediate were added to the reaction flask, and the mixture was heated until the raw materials melted. 0.2 mmol of zinc acetate was added, and the mixture was heated to 210°C for ester exchange reaction for 6 h. 0.48 mmol of ethylene glycol antimony was added, and the mixture was heated to 270°C and decompressed to 8 Pa for 3 h. The mixture was cooled to room temperature and dried to obtain a waterproof and antibacterial copolyester polymer.

[0045] (4) 100 g of vacuum-dried PET polyester chips and 15 g of waterproof and antibacterial copolyester polymer were placed in a twin-screw extruder for melt blending and extrusion granulation. The screw temperature of the twin-screw extruder was 240°C and the screw speed was set to 25 r / min. Then, melt spinning was carried out on a high-speed composite spinning machine at a spinning speed of 800 m / min and a spinning machine temperature of 260°C. After the nascent fibers were balanced, they were stretched and wound on a parallel stretching machine. The hot roller temperature of the stretching machine was 80°C, the stretching speed was 300 m / min, and the stretching multiple was 5.5 to obtain a waterproof and antibacterial polyester fiber fabric.

[0046] Example 4

[0047] (1) Under nitrogen atmosphere, 35 mmol of N,N′-bis(2-hydroxyethyl)ethylenediamine and 220 mL of dichloromethane were added to a reaction flask. After stirring, 110 mmol of N,N-diisopropylethylamine and 76.3 mmol of N,N′-di-Boc-S-methylisothiourea were added. The mixture was reacted at 30°C for 15 h, concentrated under reduced pressure, and purified by column chromatography (the volume ratio of n-hexane to ethyl acetate was 2:1) to obtain a biguanide alcohol tertiary amine intermediate.

[0048] (2) Under nitrogen atmosphere, 28 mmol of the biguanide alcohol tertiary amine intermediate and 460 mL of N,N-dimethylformamide were added to a reaction flask. After stirring, 74.2 mmol of perfluorodecylethyl iodide was added. The mixture was reacted at 125 °C for 32 h. The mixture was concentrated under reduced pressure and dried to obtain the biguanide alcohol quaternary ammonium salt perfluoro intermediate.

[0049] (3) Under nitrogen atmosphere, 10 mmol of dimethyl terephthalate and 10.8 mol of biguanide quaternary ammonium salt perfluoro intermediate were added to the reaction flask, and the mixture was heated until the raw materials melted. 0.035 mmol of zinc acetate was added, and the mixture was heated to 215°C for ester exchange reaction for 4 h. 0.1 mmol of ethylene glycol antimony was added, and the mixture was heated to 275°C and decompressed to 95 Pa for reaction for 3 h. The mixture was cooled to room temperature and dried to obtain a waterproof and antibacterial copolyester polymer.

[0050] (4) 100 g of vacuum-dried PET polyester chips and 20 g of waterproof and antibacterial copolyester polymer were placed in a twin-screw extruder for melt blending and extrusion granulation. The screw temperature of the twin-screw extruder was 245°C and the screw speed was set to 35 r / min. Then, melt spinning was carried out on a high-speed composite spinning machine at a spinning speed of 1100 m / min and a spinning machine temperature of 280°C. After the nascent fibers were balanced, they were stretched and wound on a parallel stretching machine. The hot roller temperature of the stretching machine was 90°C, the stretching speed was 360 m / min, and the stretching multiple was 5.8 to obtain a waterproof and antibacterial polyester fiber fabric.

[0051] Example 5

[0052] (1) Under nitrogen atmosphere, 25 mmol of N,N′-bis(2-hydroxyethyl)ethylenediamine and 200 mL of dichloromethane were added to a reaction flask. After stirring, 80 mmol of N,N-diisopropylethylamine and 54 mmol of N,N′-di-Boc-S-methylisothiourea were added. The mixture was reacted at 35°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 a biguanide alcohol tertiary amine intermediate.

[0053] (2) Under nitrogen atmosphere, 20 mmol of the biguanide alcohol tertiary amine intermediate and 350 mL of N,N-dimethylformamide were added to a reaction flask. After stirring, 56 mmol of perfluorodecylethyl iodide was added. The mixture was reacted at 125 °C for 48 h. The mixture was concentrated under reduced pressure and dried to obtain the biguanide alcohol quaternary ammonium salt perfluoro intermediate.

[0054] (3) Under nitrogen atmosphere, add 10 mmol of dimethyl terephthalate and 11 mol of biguanide quaternary ammonium salt perfluoro intermediate into a reaction flask, heat until the raw materials melt, add 0.05 mmol of zinc acetate, heat to 220°C for ester exchange reaction for 6 h, add 0.11 mmol of ethylene glycol antimony, heat to 280°C, reduce pressure to 100 Pa and react for 2 h, cool to room temperature, and dry to obtain a waterproof and antibacterial copolyester polymer.

[0055] (4) 100 g of vacuum-dried PET polyester chips and 25 g of waterproof and antibacterial copolyester polymer were placed in a twin-screw extruder for melt blending and extrusion granulation. The screw temperature of the twin-screw extruder was 255°C and the screw speed was set to 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 nascent fibers were balanced, they were stretched and wound on a parallel stretching machine. The hot roller temperature of the stretching machine was 90°C, the stretching speed was 350 m / min, and the stretching multiple was 6, to obtain a waterproof and antibacterial polyester fiber fabric.

[0056] Comparative Example 1

[0057] (1) Under nitrogen atmosphere, 10 mmol of dimethyl terephthalate and 9.5 mol of biguanidine tertiary amine intermediate (prepared in Example 1) were added to a reaction flask, heated until the raw materials melted, 0.04 mmol of zinc acetate was added, heated to 215°C for ester exchange reaction for 5 h, 0.09 mmol of ethylene glycol antimony was added, the temperature was raised to 280°C, the pressure was reduced to 90 Pa, the reaction was carried out for 2 h, the reaction was cooled to room temperature, and the copolyester polymer was obtained after drying.

[0058] (2) 100 g of vacuum-dried PET polyester chips and 5 g of copolyester polymer were placed in a twin-screw extruder for melt blending and extrusion granulation. The screw temperature of the twin-screw extruder was 250°C and the screw speed was set to 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, they were stretched and wound on a parallel stretching machine. The hot roller temperature of the stretching machine was 85°C, the stretching speed was 350 m / min, and the stretching multiple was 6, thereby obtaining a polyester fiber fabric.

[0059] Comparative Example 2

[0060] (1) Under nitrogen atmosphere, 10 mmol of dimethyl terephthalate and 9.5 mol of N,N′-bis(2-hydroxyethyl)ethylenediamine were added to a reaction flask and heated until the raw materials melted. 0.04 mmol of zinc acetate was added and heated to 215°C for ester exchange reaction for 5 h. 0.09 mmol of antimony glycol was added and the temperature was raised to 280°C and the pressure was reduced to 90 Pa for reaction for 2 h. The mixture was cooled to room temperature and dried to obtain a copolyester polymer.

[0061] (2) 100 g of vacuum-dried PET polyester chips and 5 g of copolyester polymer were placed in a twin-screw extruder for melt blending and extrusion granulation. The screw temperature of the twin-screw extruder was 250°C and the screw speed was set to 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, they were stretched and wound on a parallel stretching machine. The hot roller temperature of the stretching machine was 85°C, the stretching speed was 350 m / min, and the stretching multiple was 6 to obtain a polyester fiber fabric.

[0062] Antibacterial performance test: The test was conducted with reference to the standard GB / T 20944.3-2008 "Evaluation of antibacterial properties of textiles Part 3: Oscillating bottle method", and the antibacterial rates of the polyester fiber fabrics prepared in the examples and comparative examples against Escherichia coli and Staphylococcus aureus were tested respectively.

[0063] Table 1 Antibacterial rate test

[0064]

[0065] It can be seen from the test results in the above table that with the increase of the content of the waterproof and antibacterial copolyester polymer, the antibacterial property of the polyester fiber fabric is gradually enhanced, wherein the antibacterial rate of Escherichia coli in Example 4 reaches 99.9%, and the antibacterial rate of Staphylococcus aureus reaches 98.2%. This is because on the one hand, the waterproof and antibacterial copolyester polymer contains quaternary ammonium salt, guanidine group and hydrophobic long chain structure, wherein the quaternary ammonium salt is adsorbed with negatively charged bacteria by electrostatic force, hydrogen bond force and the like, aggregated on the cell wall, hindering the action of cell lysozyme, destroying the cell surface structure, so that the basic function of the cell membrane is affected; guanidine group can destroy the biological activity of phospholipids and the structure of cell membrane, quickly adsorb to the negatively charged bacterial cell membrane, and exchange ions with cations in the cell membrane, resulting in increased permeability of the cell membrane, so that the substances in the cell leak out; the hydrophobic long chain is embedded in the bacterial surface, combined with the phospholipid bilayer in the cell membrane, producing a chamber resistance effect, hindering the exchange of substances inside and outside the cell, and finally killing the bacteria. Comparative Example 1 contains only guanidine antibacterial groups and has limited antibacterial effect; Comparative Example 2 does not contain any antibacterial groups and has no antibacterial effect.

[0066] Antibacterial durability test: The prepared polyester fiber fabric was cut into a size of 5cm×5cm, placed in a beaker with a diameter of 50cm, washed with 50mL of a 2% sodium dodecyl sulfate aqueous solution, stirred at 300rpm and 25°C, and each 10 minutes was a washing cycle. After that, it was washed with deionized water, and after drying, the washed samples were tested for antibacterial durability according to the standard GB / T20944.3-2008 "Evaluation of Antibacterial Properties of Textiles Part 3: Oscillating Bottle Method".

[0067] Table 2 Antimicrobial persistence test

[0068]

[0069] From the test results in the above table, it can be seen that with the increase of the content of waterproof and antibacterial copolyester polymer, the antibacterial and durable performance of polyester fiber fabric is gradually enhanced. After 50 washes, the polyester fiber fabric still has a high inhibition 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 to avoid the migration of antibacterial groups and better exert the antibacterial performance against bacteria.

[0070] Water absorption test: Cut the prepared polyester fiber fabric into a size of 5cm×5cm, put it into a beaker with a diameter of 200cm filled with deionized water, and completely soak it for 30 minutes. Calculate the weight difference to calculate the water absorption rate. Measure 3 times and take the average value. Water absorption rate = (W2-W1) / W1×100%, where W1 and W2 are the weight of the fiber fabric before and after soaking, respectively.

[0071] 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 3 times to take the average value.

[0072] Table 3 Waterproof performance test

[0073]

[0074] From the test results in the above table, it can be seen that with the increase of the content of waterproof and antibacterial copolyester polymer, the waterproof performance of polyester fiber fabric is gradually enhanced. This is because the waterproof and antibacterial copolyester polymer contains organic fluorine and the CF bond energy is high. Compared with hydrogen atoms, fluorine atoms are more easily embedded in the polymer, blocking the channels for water molecules to migrate into the coating. A stable protective layer can be formed on the surface of the fiber fabric, wrapping the fiber to prevent water from penetrating into the fiber, thereby playing a waterproof role; in addition, the long alkyl 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, 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 washings without failure.

[0075] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for preparing a waterproof and antibacterial 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; 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, the spinning speed is 800-1200m / min, the spinning machine temperature is 260-290°C, after the primary fibers are balanced, drawing and winding are performed on a parallel drawing machine to obtain a waterproof and antibacterial polyester fiber fabric.

2. The method for preparing the waterproof and antibacterial polyester fiber fabric according to claim 1, characterized in that: 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.

3. The method for preparing the waterproof and antibacterial polyester fiber fabric according to claim 1, characterized in that: In the step (2), the ratio of PET polyester chips to waterproof and antibacterial copolyester polymer is 100g:(5-25)g.

4. The method for preparing the waterproof and antibacterial polyester fiber fabric according to claim 1, characterized in that: In the step (2), 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 drawing machine is 80-90°C, the drawing speed is 300-400 m / min, and the drawing multiple is 5.5-6.

5.

5. The method for preparing the waterproof and antibacterial polyester fiber fabric according to claim 1, characterized in that: 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.

6. The method for preparing the waterproof and antibacterial polyester fiber fabric according to claim 5, 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.

7. The method for preparing the waterproof and antibacterial polyester fiber fabric according to claim 5, characterized in that: In step S1, the reaction temperature is 20-35° C. and the reaction time is 8-16 h.

8. The method for preparing the waterproof and antibacterial polyester fiber fabric according to claim 5, 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.

9. The method for preparing the waterproof and antibacterial polyester fiber fabric according to claim 5, characterized in that: In step S2, the reaction temperature is 110-130° C. and the reaction time is 24-48 hours.

10. A waterproof and antibacterial polyester fiber fabric, characterized in that: Obtained by the preparation method according to any one of claims 1 to 9.

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