Functional modified regenerated cellulose fiber as well as preparation method and application thereof

Abstract

The invention relates to the technical field of regenerated cellulose, in particular to functional modified regenerated cellulose fiber as well as a preparation method and application thereof, and the functional modified regenerated cellulose fiber is prepared from the following raw materials in parts by mass: 100-120 parts of regenerated cellulose fiber, 2-5 parts of antibacterial agent and 1250-1350 parts of ionic liquid. The regenerated cellulose fiber disclosed by the invention is good in tensile property, can be attached to other functional materials, and has relatively good antibacterial property and heat-resistant stability.

Description

Technical Field

[0001] The invention relates to the technical field of regenerated cellulose, and in particular to a functional modified regenerated cellulose fiber and a preparation method and application thereof. Background Art

[0002] Regenerated cellulose fiber is a fiber extracted from natural cellulose resources and obtained through chemical treatment and mechanical processing. The production process of this fiber does not change the chemical structure of cellulose, but only changes its physical form to produce textile materials with better performance. The structural composition of regenerated cellulose fiber is similar to that of cotton, but compared with cotton fiber, it has better moisture absorption and air permeability, and is known as "breathing fabric". In addition, regenerated cellulose fiber also has some excellent properties of silk, such as soft feel, plump texture and smooth touch, as well as excellent drape and silk-like luster. Regenerated cellulose fiber has high thermal stability and light stability, and its strength and elongation can meet the needs of most textiles. The environmental protection characteristics of regenerated cellulose fiber also make it one of the sustainable development textile materials. Due to its wide range of raw materials, including wood, bamboo, cotton linters, etc., the production of regenerated cellulose fiber has relatively little impact on the environment, and its waste can be naturally biodegraded, without additives, heavy metals, harmful chemicals, skin affinity and non-irritating, it is an excellent environmentally friendly "green" fiber.

[0003] Despite this, there are still many areas that need to be improved for regenerated cellulose fiber to be more suitable for use by contemporary people. For example, when it is used in textiles, it is essential to constantly wash and rub it, which is easy to produce deformation and wrinkles that cannot be restored. In response to this problem, patent number CN110616466B discloses "a regenerated cellulose strong yarn and its preparation method". It is made by spinning solution, spinning, and stretching. The regenerated cellulose strong yarn can simultaneously meet the requirements of high strength and high modulus and low fibrillation, and has high breaking strength. For example, CN102586919B discloses "a dimensionally stable regenerated cellulose fiber and its preparation method". The cellulose raw material is subjected to impregnation, pressing, crushing, aging, yellowing, continuous dissolution, filtration, and degassing processes to prepare spinning viscose, and then spinning, and then adding some denaturants, cross-linking agents, etc. to obtain the regenerated cellulose fiber. The regenerated cellulose fiber has the characteristics of small wet tensile elongation, good stability, and low hygroscopic expansion rate.

[0004] However, in the process of making textiles from regenerated cellulose fibers, some functional materials have poor compatibility with the regenerated cellulose fibers. After being made into textiles, the regenerated cellulose fibers have poor heat resistance, and the growth of bacteria during use has an impact on human health. In addition, the textiles after soaking and washing need to be aired, which is prone to aging and yellowing, affecting their use. The above-mentioned patents do not mention and solve the problems of poor heat resistance, antibacterial properties, anti-aging and yellowing, and poor compatibility with other functional materials.

[0005] Therefore, it is urgent to develop a functional modified regenerated cellulose fiber that has good tensile strength, can adhere to other functional materials, and has good antibacterial properties and heat resistance. Summary of the invention

[0006] The main purpose of the present invention is to provide a functional modified regenerated cellulose fiber and its preparation method and application. The regenerated cellulose fiber has good tensile strength, can be attached to other functional materials, and has good antibacterial properties and heat resistance stability.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] On one hand, the present invention provides a functional modified regenerated cellulose fiber, comprising the following raw materials in parts by weight: 100-120 parts of modified regenerated cellulose fiber, 2-5 parts of antibacterial agent and 1250-1350 parts of ionic liquid.

[0009] Textiles can be seen everywhere in people's daily lives. Regenerated cellulose fiber has gradually become one of the main raw materials for textiles due to its environmental protection, high hygroscopicity, skin-friendliness and easy dyeing. However, there are still many problems with regenerated cellulose fiber that need to be improved. For example, when it is used in textiles, it is essential to constantly wash and rub it, which can easily cause deformation and wrinkles that cannot be restored. At the same time, after regenerated cellulose fiber is made into textiles, it will affect human health due to the growth of bacteria when used.

[0010] The functional modified regenerated cellulose fiber of the present application is prepared with modified regenerated cellulose fiber, antibacterial agent and ionic liquid as main raw materials, has good tensile strength, can be attached to other functional materials, and has good antibacterial performance and heat stability.

[0011] In some embodiments, the ionic liquid is any one of [BMIM]Cl, [EMIM][DEP], [Mmim]Cl, and [BMIM]Ac.

[0012] In some embodiments, the method for preparing the antibacterial agent comprises the following steps:

[0013] A1. Mix chitosan, epichlorohydrin, glycidyltrimethylammonium chloride, sodium bicarbonate and isopropanol, heat to 30-40°C and stir for 12-14h. After the reaction is completed, filter, rinse with ethanol and dry to obtain epoxy-modified chitosan quaternary ammonium salt;

[0014] A2. Add the epoxy-modified chitosan quaternary ammonium salt and 4,4'-oxydiphthalic anhydride in step A1 into N,N-dimethylformamide, raise the temperature to 100-110°C and stir at a constant temperature for 15-17 hours. After the reaction is completed, reduce the pressure, concentrate and dry, wash with ethanol and then dry to obtain an antibacterial agent.

[0015] Chitosan is a natural biodegradable polymer compound that is widely used in the field of textiles. It has certain antibacterial properties, but its antibacterial ability is limited. At the same time, its tensile properties are not applicable when used in textiles.

[0016] The antibacterial agent of the present application not only has excellent antibacterial properties, but also has higher tensile properties. The reason may be that the applicant uses chitosan, epichlorohydrin, and epoxypropyltrimethylammonium chloride as main raw materials, so that the prepared epoxy-modified chitosan quaternary ammonium salt contains a large amount of quaternary ammonium salt structure, which improves its antibacterial properties. At the same time, the epoxy group reacts with 4,4'-oxydiphthalic anhydride to cross-link the chitosan, thereby improving its tensile properties.

[0017] In addition, on the one hand, the carboxyl groups can also interact with the hydroxyl groups on the surface of the modified regenerated cellulose fibers; on the other hand, the surface of the modified regenerated cellulose fibers is loaded with a large amount of porous silica, which can adsorb antibacterial agents, thereby improving the ability of the antibacterial agents to adhere to the modified regenerated cellulose fibers and improving the antibacterial stability of the functional modified regenerated cellulose fibers.

[0018] In some embodiments, in step A1, the mass ratio of chitosan, epichlorohydrin and glycidyltrimethylammonium chloride is 1:(1-3):(2-4).

[0019] Preferably, in step A1, the mass ratio of chitosan, epichlorohydrin and glycidyltrimethylammonium chloride is 1:2:3.

[0020] In some embodiments, in step A1, the molar ratio of sodium bicarbonate to epichlorohydrin is (1.2-1.4):1.

[0021] Preferably, in step A1, the molar ratio of sodium bicarbonate to epichlorohydrin is 1.3:1.

[0022] In some embodiments, the molar ratio of epichlorohydrin to 4,4'-oxydiphthalic anhydride is 1:(1-1.3).

[0023] Preferably, the molar ratio of epichlorohydrin to 4,4'-oxydiphthalic anhydride is 1:1.2.

[0024] In some embodiments, the method for preparing modified regenerated cellulose fiber comprises the following steps:

[0025] B1. Dissolve 0.032g TEMPO and 0.2g NaBr in 200ml deionized water, heat to 35-45°C and stir to dissolve, then add 1g regenerated cellulose fiber and stir evenly to obtain material A;

[0026] B2, prepare 1-2 mmol / L NaClO solution, and adjust the pH value of the system to 10-11 to obtain material B;

[0027] B3, adding material B to material A, adjusting the pH value of the system to 10-11 with sodium hydroxide solution, reacting until the pH does not change, then adding 10 mL of ethanol, filtering, washing with ethanol, and drying to obtain oxidized regenerated cellulose fibers;

[0028] B4, placing the porous silica in an environment of 200-300°C for 13-16 hours, cooling to room temperature, adding it to dichlorothionyl at -10-0°C, then heating to room temperature and stirring at a constant temperature for 2-5 hours, filtering after the reaction is completed, and drying to obtain chlorinated porous silica;

[0029] B5. Mix the chlorinated porous silica and diamine compound in step B4 and the oxidized regenerated cellulose fiber in step B3 and add them into N,N-dimethylformamide, heat to 55-65°C, add N,N'-dicyclohexylcarbodiimide, stir at constant temperature for 18-20 hours, filter after the reaction is completed, wash with water and dry to obtain modified regenerated cellulose fiber.

[0030] Functional fibers are a popular research and development direction in the current spinning industry. Functional fibers usually achieve their functions by adding specific functional particles, coatings or special spinning technologies during the fiber manufacturing process. For example, by adding antibacterial agents to the fibers, fibers with antibacterial functions can be produced, and by coating the fiber surface with anti-ultraviolet materials, anti-ultraviolet fibers can be produced. However, in the actual research and development process, the compatibility of regenerated cellulose fibers with some functional materials is low, which seriously affects the stability of the fabric.

[0031] The functional modified regenerated cellulose fiber of the present application can be adapted to more functional materials, solving the problem of poor compatibility between the above-mentioned regenerated cellulose fiber and functional materials. The reason may be that the modified regenerated cellulose fiber has its surface functional groups' activity increased by oxidation, and then the silica with adsorption function is stably grafted onto the surface of the regenerated cellulose fiber by amidation reaction. When the modified cellulose fiber is in use, the porous silica on its surface can adsorb functional materials, thereby improving the compatibility between the functional materials and the regenerated cellulose fiber and improving the stability of the fabric.

[0032] In some embodiments, in step B5, the diamine compound is any one of 1,3-phenylenediamine, 4-aminobenzylamine and 3-aminobenzylamine.

[0033] The present application selects specific diamine compounds as modifiers for modifying regenerated cellulose fibers, which can not only stably graft porous silica onto the surface of the regenerated cellulose fibers, but also improve the heat resistance stability of the functional modified regenerated cellulose fibers.

[0034] In some embodiments, in step B5, the mass ratio of the chlorinated porous silica, the diamine compound and the oxidized regenerated cellulose fiber is 1:(1-1.4):(4-6).

[0035] Preferably, in step B5, the mass ratio of the chlorinated porous silica, the diamine compound and the oxidized regenerated cellulose fiber is 1:1.2:5.

[0036] On the other hand, the present invention provides a method for preparing functional modified regenerated cellulose fibers, comprising the following steps: mixing the dried modified regenerated cellulose fibers and an antibacterial agent, adding an ionic liquid, vacuum kneading and dissolving at 95-100° C. for 3-5 hours, then degassing, and then dry-jet wet spinning at 90-95° C. to obtain functional modified regenerated cellulose fibers.

[0037] In another aspect, the present invention provides a use of functional modified regenerated cellulose fiber in fabrics.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] (1) The functional modified regenerated cellulose fiber of the present invention uses modified regenerated cellulose fiber, antibacterial agent and ionic liquid as main raw materials, and is obtained by vacuum kneading, degassing and spinning. The functional regenerated cellulose fiber has good tensile strength, can be attached to other functional materials, and has good antibacterial properties and heat stability.

[0040] (2) The antibacterial agent of the present invention is prepared using chitosan, epichlorohydrin, and epoxypropyltrimethylammonium chloride as main raw materials. The epoxy-modified chitosan quaternary ammonium salt contains a large amount of quaternary ammonium salt structure to improve its antibacterial properties. At the same time, the epoxy group reacts with 4,4'-oxydiphthalic anhydride to cross-link the chitosan, thereby improving its tensile properties. In addition, the carboxyl group therein can also interact with the hydroxyl group on the surface of the modified regenerated cellulose fiber, and the surface of the modified regenerated cellulose fiber is loaded with a large amount of porous silica, which can adsorb other functional materials such as antibacterial agents, thereby improving the ability of functional materials such as antibacterial agents to adhere to the modified regenerated cellulose fiber, improving the antibacterial stability of the modified regenerated cellulose fiber, and having good compatibility with other functional materials.

[0041] (3) The modified regenerated cellulose fiber of the present invention increases the activity of its surface functional groups through oxidation, and then utilizes an amidation reaction to stably graft silica with adsorption function onto the surface of the regenerated cellulose fiber. When the modified cellulose fiber is in use, the porous silica on its surface can adsorb functional materials, thereby improving the compatibility of functional materials with the regenerated cellulose fiber and improving the stability of the fabric.

[0042] (4) The present invention selects specific diamine compounds to prepare modified regenerated cellulose fibers, which can improve the heat resistance and stability of functional modified regenerated cellulose fibers. DETAILED DESCRIPTION

[0043] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] In the following preparation examples, embodiments and comparative examples, chitosan was purchased from Huantai County Jinhu Crust Products Co., Ltd.; [BMIM]Cl was purchased from Wuhan Haishan Technology Co., Ltd.; and regenerated cellulose fiber was purchased from Shandong Xuzheng Textile Co., Ltd.

[0045] Preparation Example 1

[0046] The preparation method of the antibacterial agent comprises the following steps:

[0047] A1, 10g chitosan, 20g epichlorohydrin, 30g glycidyl trimethylammonium chloride, 23.6g sodium bicarbonate and 800mL isopropanol were mixed, the temperature was raised to 35°C and stirred at constant temperature for 13h, after the reaction was completed, the mixture was filtered, rinsed with ethanol and dried to obtain epoxy-modified chitosan quaternary ammonium salt;

[0048] A2. Add the epoxy-modified chitosan quaternary ammonium salt in step A1 and 80.5 g of 4,4'-oxydiphthalic anhydride to 1 L of N,N-dimethylformamide, heat to 105° C. and stir at constant temperature for 16 h. After the reaction is completed, concentrate and dry under reduced pressure, wash with ethanol and then dry to obtain an antibacterial agent.

[0049] Preparation Example 2

[0050] The preparation method of the antibacterial agent is the same as that of Preparation Example 1, except that the amount of glycidyltrimethylammonium chloride is 15 g.

[0051] Preparation Example 3

[0052] The preparation method of the antibacterial agent is the same as that of Preparation Example 1, except that the amount of glycidyltrimethylammonium chloride is 45 g.

[0053] Preparation Example 4

[0054] The preparation method of the antibacterial agent is the same as that of Preparation Example 1, except that the amount of 4,4'-oxydiphthalic anhydride is 90 g.

[0055] Preparation Example 5

[0056] The preparation method of modified regenerated cellulose fiber comprises the following steps:

[0057] B1. Dissolve 30 g of TEMPO and 20 g of NaBr in 3 L of deionized water, heat to 40 °C and stir to dissolve, then add 100 g of regenerated cellulose fiber and stir evenly to obtain material A;

[0058] B2, prepare 5L 1.5mmol / L NaClO solution, and adjust the pH value of the system to 10.5 with 1mol / L hydrochloric acid solution to obtain material B;

[0059] B3, adding material B to material A, adjusting the pH value of the system to 10.5 with 1 mol / L sodium hydroxide solution, reacting until the pH does not change, then adding 1.5 L ethanol, filtering, washing with ethanol, and drying to obtain oxidized regenerated cellulose fibers;

[0060] B4, placing 40g of porous silica in a 250°C environment for 15h, cooling to room temperature, adding to 600mL of -5°C thionyl chloride, then heating to room temperature and stirring at a constant temperature for 3h, filtering after the reaction is completed, and drying to obtain chlorinated porous silica;

[0061] B5. Mix 20 g of the chlorinated porous silica prepared in step B4, 24 g of 1,3-phenylenediamine and 100 g of the oxidized regenerated cellulose fiber prepared in step B3 and add them to 2 L of N,N-dimethylformamide. Heat the mixture to 60°C, add 60 g of N,N'-dicyclohexylcarbodiimide and stir at the constant temperature for 19 h. After the reaction is completed, filter the mixture, wash it with water and dry it to obtain modified regenerated cellulose fiber.

[0062] Preparation Example 6

[0063] The preparation method of the modified regenerated cellulose fiber has the same specific implementation as that of Preparation Example 5, except that an equal mass of 1,5-diaminopentane is used instead of 1,3-phenylenediamine.

[0064] Preparation Example 7

[0065] The method for preparing modified regenerated cellulose fiber has the same specific implementation as that of Preparation Example 5, except that the mass of the oxidized regenerated cellulose fiber in step B5 is 70 g.

[0066] Example 1

[0067] A functional modified regenerated cellulose fiber comprises the following raw materials in parts by weight: 110 parts of modified regenerated cellulose fiber, 3 parts of antibacterial agent and 1300 parts of [BMIM]Cl.

[0068] Among them, the antibacterial agent is prepared by Preparation Example 1, and the modified regenerated cellulose fiber is prepared by Preparation Example 5.

[0069] The preparation method of functional modified regenerated cellulose fiber comprises the following steps: mixing the dried modified regenerated cellulose fiber and the antibacterial agent, adding [BMIM]Cl, kneading and dissolving in a 98°C experimental kneader in a vacuum for 4 hours, then degassing, and then performing dry-jet wet spinning through a porous spinning device at 92°C to obtain the modified regenerated cellulose fiber.

[0070] Example 2

[0071] A functional modified regenerated cellulose fiber comprises the following raw materials in parts by weight: 100 parts of modified regenerated cellulose fiber, 2 parts of antibacterial agent and 1250 parts of [BMIM]Cl.

[0072] Among them, the antibacterial agent is prepared by Preparation Example 1, and the modified regenerated cellulose fiber is prepared by Preparation Example 5.

[0073] The preparation method of functional modified regenerated cellulose fiber comprises the following steps: mixing the dried modified regenerated cellulose fiber and the antibacterial agent and adding [BMIM]Cl, kneading and dissolving in a 95°C experimental kneader under vacuum for 5 hours, then degassing, and then performing dry-jet wet spinning through a 90°C porous spinning device to obtain the modified regenerated cellulose fiber.

[0074] Example 3

[0075] A functional modified regenerated cellulose fiber comprises the following raw materials in parts by weight: 120 parts of modified regenerated cellulose fiber, 5 parts of antibacterial agent and 1350 parts of [BMIM]Cl.

[0076] Among them, the antibacterial agent is prepared by Preparation Example 1, and the modified regenerated cellulose fiber is prepared by Preparation Example 5.

[0077] The preparation method of functional modified regenerated cellulose fiber comprises the following steps: mixing the dried modified regenerated cellulose fiber and the antibacterial agent and adding [BMIM]Cl, kneading and dissolving in a 100°C experimental kneader in a vacuum for 3 hours, then degassing, and then performing dry-jet wet spinning in a 95°C porous spinning device to obtain the modified regenerated cellulose fiber.

[0078] Example 4

[0079] A functional modified regenerated cellulose fiber and a preparation method thereof. The specific implementation manner is the same as that of Example 1, except that the antibacterial agent is prepared by Preparation Example 2.

[0080] Example 5

[0081] A functional modified regenerated cellulose fiber and a preparation method thereof. The specific implementation manner is the same as that of Example 1, except that the antibacterial agent is prepared by Preparation Example 3.

[0082] Example 6

[0083] A functional modified regenerated cellulose fiber and a preparation method thereof. The specific implementation manner is the same as that of Example 1, except that the antibacterial agent is prepared by Preparation Example 4.

[0084] Example 7

[0085] A functional modified regenerated cellulose fiber and a preparation method thereof. The specific implementation manner is the same as that of Example 1, except that the modified regenerated cellulose fiber is prepared by Preparation Example 6.

[0086] Example 8

[0087] A functional modified regenerated cellulose fiber and a preparation method thereof. The specific implementation manner is the same as that of Example 1, except that the modified regenerated cellulose fiber is prepared by Preparation Example 7.

[0088] Comparative Example 1

[0089] A functional modified regenerated cellulose fiber and a preparation method thereof. The specific implementation manner is the same as that of Example 1, except that an equal mass portion of chitosan is used instead of an antibacterial agent.

[0090] Comparative Example 2

[0091] A functional modified regenerated cellulose fiber and a preparation method thereof. The specific implementation manner is the same as that of Example 1, except that an equal mass portion of regenerated cellulose fiber is used instead of the modified regenerated cellulose fiber.

[0092] Performance Test:

[0093] (1) Antibacterial rate: Refer to the standard GB / T20944.3-2008 "Evaluation of antibacterial properties of textiles Part 3: Oscillation method" to test the antibacterial rate of regenerated cellulose fiber against Escherichia coli and Staphylococcus aureus;

[0094] (2) Anti-aging performance: Refer to GB / T18830-2009 “Evaluation of UV protection performance of textiles” to test the anti-aging performance of the samples to be tested;

[0095] (3) Breaking strength: Refer to GB / T14344-2008 "Test method for tensile properties of chemical fiber filaments" to test the breaking strength;

[0096] (4) Heat resistance test: The functional modified regenerated cellulose fiber was placed in a 200°C environment for 10 min, and the breaking strength performance in method (3) was tested again;

[0097] (5) Tensile resilience test: Cut a 10 cm long piece of regenerated cellulose fiber, clamp its two ends in a tensile testing machine, and stretch it 50 times. Then, calculate the tensile resilience according to the following formula:

[0098] Tensile resilience (%) = (rebound length - initial length) / initial length × 100%.

[0099] The regenerated cellulose fibers of the embodiments and comparative examples were tested according to the above test method. The results are shown in Table 1.

[0100] Table 1

[0101]

[0102] According to the above results, it is found that the functional modified regenerated cellulose fibers of Examples 1 to 3 have good heat stability, anti-aging performance, antibacterial performance and mechanical properties; in Example 4, due to the change in the mass ratio of chitosan, epichlorohydrin and epoxypropyltrimethylammonium chloride, the antibacterial performance of the functional modified regenerated cellulose fiber decreases, but the resilience and breaking strength are slightly improved; in Example 5, due to the change in the mass ratio of chitosan, epichlorohydrin and epoxypropyltrimethylammonium chloride, the content of epoxypropyltrimethylammonium chloride increases, resulting in a slight decrease in the resilience of the functional modified regenerated cellulose fiber; in Example 6, due to the change in the molar ratio of epichlorohydrin to 4,4'-oxydiphthalic anhydride, the crosslinking density of the functional modified regenerated cellulose fiber is too large, which makes Its rebound performance is reduced; in Example 7, due to the use of equal mass of 1,5-diaminopentane instead of 1,3-phenylenediamine, the heat resistance of the functional modified regenerated cellulose fiber is reduced; in Example 8, due to the change of the mass ratio of chlorinated porous silica, diamine compounds and oxidized regenerated cellulose fibers, the breaking strength and rebound performance of the functional modified regenerated cellulose fibers are reduced, but the heat resistance is enhanced; in Comparative Example 1, due to the use of equal mass parts of chitosan instead of antibacterial agent, the breaking strength and antibacterial performance of the regenerated cellulose fiber are reduced; in Comparative Example 2, due to the use of equal mass parts of regenerated cellulose fibers instead of modified regenerated cellulose fibers, the anti-aging performance and heat resistance of the functional modified regenerated fiber are reduced, but the breaking strength and rebound performance at room temperature are slightly enhanced.

[0103] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A functional modified regenerated cellulose fiber, characterized in that: The invention comprises the following raw materials in parts by weight: 100 to 120 parts of modified regenerated cellulose fibers, 2 to 5 parts of antibacterial agents and 1250 to 1350 parts of ionic liquids.

2. The functional modified regenerated cellulose fiber according to claim 1, characterized in that The preparation method of the antibacterial agent comprises the following steps: A1. Mix chitosan, epichlorohydrin, glycidyltrimethylammonium chloride, sodium bicarbonate and isopropanol, heat to 30-40°C and stir for 12-14h. After the reaction is completed, filter, rinse with ethanol and dry to obtain epoxy-modified chitosan quaternary ammonium salt; A2. Add the epoxy-modified chitosan quaternary ammonium salt and 4,4'-oxydiphthalic anhydride in step A1 into N,N-dimethylformamide, raise the temperature to 100-110°C and stir at a constant temperature for 15-17 hours. After the reaction is completed, reduce the pressure, concentrate and dry, wash with ethanol and then dry to obtain an antibacterial agent.

3. The functional modified regenerated cellulose fiber according to claim 2, characterized in that In step A1, the mass ratio of chitosan, epichlorohydrin and glycidyltrimethylammonium chloride is 1:(1-3):(2-4).

4. The functional modified regenerated cellulose fiber according to claim 2, characterized in that In step A1, the molar ratio of sodium bicarbonate to epichlorohydrin is (1.2-1.4):

1.

5. The functional modified regenerated cellulose fiber according to claim 2, characterized in that: The molar ratio of epichlorohydrin to 4,4'-oxydiphthalic anhydride is 1:(1-1.3).

6. The functional modified regenerated cellulose fiber according to claim 1, characterized in that: The method for preparing the modified regenerated cellulose fiber comprises the following steps: B1. Dissolve TEMPO and NaBr in deionized water, heat to 35-45°C and stir to dissolve, then add regenerated cellulose fiber and stir evenly to obtain material A; B2, prepare 1-2 mmol / L NaClO solution, and adjust the pH value of the system to 10-11 to obtain material B; B3, adding material B to material A, adjusting the pH value of the system to 10-11 with sodium hydroxide solution, reacting until the pH does not change, then adding ethanol, filtering, washing with ethanol, and drying to obtain oxidized regenerated cellulose fiber; B4, placing the porous silica in an environment of 200-300°C for 13-16 hours, cooling to room temperature, adding it to dichlorothionyl at -10-0°C, then heating to room temperature and stirring at a constant temperature for 2-5 hours, filtering after the reaction is completed, and drying to obtain chlorinated porous silica; B5. Mix the chlorinated porous silica and diamine compound in step B4 and the oxidized regenerated cellulose fiber in step B3 and add them into N,N-dimethylformamide, heat to 55-65°C, add N,N'-dicyclohexylcarbodiimide, stir at constant temperature for 18-20 hours, filter after the reaction is completed, wash with water and dry to obtain modified regenerated cellulose fiber.

7. The functional modified regenerated cellulose fiber according to claim 6, characterized in that In step B5, the diamine compound is any one of 1,3-phenylenediamine, 4-aminobenzylamine and 3-aminobenzylamine.

8. The functional modified regenerated cellulose fiber according to claim 6, characterized in that In step B5, the mass ratio of the chlorinated porous silica, the diamine compound and the oxidized regenerated cellulose fiber is 1:(1-1.4):(4-6).

9. A method for preparing the functional modified regenerated cellulose fiber according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: mixing the dried modified regenerated cellulose fiber and the antibacterial agent, adding the ionic liquid, kneading and dissolving in vacuum at 95-100° C. for 3-5 hours, then degassing, and then performing dry-jet wet spinning at 90-95° C. to obtain functional modified regenerated cellulose fiber.

10. Use of the functional modified regenerated cellulose fiber according to any one of claims 1 to 8 in fabrics.

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