Preparation method of antibacterial and antioxidant cotton fiber modified by organic acid

Abstract

The invention discloses a preparation method of organic acid modified antibacterial and antioxidant cotton fibers, which comprises the following steps: (1) taking a certain amount of cotton fibers for later use; (2) soaking and alkalizing the cotton fibers in a sodium hydroxide aqueous solution, and reacting at 30-40 DEG C for 10-20 minutes, so that alcoholic hydroxyl groups form alcohol anions, and reaction active centers in a cellulose structure are increased; (3) adjusting the temperature to 50-70 DEG C, adding 5-chlorosalicylic acid, and carrying out etherification reaction for 1-6 hours to remove halogen and form an ether bond with alkali cellulose; (4) after the reaction is finished, taking out the cotton fibers, washing and drying; and (5) preparing the antibacterial and antioxidant cotton fiber modified by the organic acid. The salicylic acid modified antibacterial cotton fiber provided by the invention can show long-term and lasting excellent antibacterial performance on the basis of keeping an inherent morphology structure, and has good anti-inflammatory and anti-oxidation effects and biological safety at the same time.

Description

Technical Field

[0001] The invention belongs to the technical field of functional fibers, and in particular relates to a method for preparing organic acid-modified antibacterial and antioxidant cotton fibers. Background Art

[0002] As people's living standards gradually improve, personal hygiene and health issues are increasingly valued. As a necessity of human life, fiber textiles are increasingly valued for their safety and hygiene functions. Under this social trend, the research on various antibacterial fabrics has developed rapidly in the past two decades. The antibacterial properties of fiber textiles have also received more extensive attention, so it is extremely important to carry out antibacterial research on textiles.

[0003] Cotton fiber is one of the most important natural textile materials in the world. It has been widely used in various fields due to its excellent properties such as comfort, warmth retention, moisture absorption and perspiration removal. However, good moisture absorption also creates suitable breeding conditions for microorganisms, which poses many safety hazards during use. Therefore, developing the antibacterial ability of cotton fiber is of great significance to expand its application range.

[0004] At present, the preparation methods of antibacterial fabrics can be roughly divided into two methods: physical modification and chemical modification. The physical method is to add antibacterial agents to fabric fibers, and the fibers and antibacterial agents are combined by physical action. The specific implementation methods include co-spinning, fiber surface modification, etc. The chemical method is to link the antibacterial agent to the fabric fibers in a chemically bonded manner. The specific implementation methods include fiber surface grafting modification, surface finishing, etc. However, the antibacterial agents used in these methods are all metal-based (silver, zinc, copper, etc.) or chemical reagent antibacterial agents (such as quaternary ammonium salts, biquadrons), all of which have certain cytotoxicity, and are therefore not suitable for occasions that are in direct contact with human skin (such as underwear worn next to the skin, etc.). For example, CN117802771A uses a sol spray growth method and a plasma surface modification method to prepare a cotton fabric with unidirectional moisture absorption and perspiration and antibacterial functions. The antibacterial rates of the treated cotton fabric against Staphylococcus aureus and Escherichia coli can reach 89.22% and 92.61%. CN118373821A discloses a method for preparing a cationic perylene diimide antibacterial agent, and grafting it onto polydopamine-modified cotton fabric to make it have good water-resistant and antibacterial properties. CN114164655B impregnates a synthetic antibacterial agent solution onto cotton fabric, so that the cotton fabric still exhibits a good antibacterial effect after washing 100 times. Patent CN114575149B first prepares a phosphate-based antibacterial sol, and then uses ultraviolet light to graft phosphate inorganic particles onto cotton fibers to obtain Ag-based phosphate-based inorganic antibacterial coupled cotton fibers.

[0005] In general, most of the current antibacterial cotton fiber products are produced by adding antibacterial agents or performing antibacterial modification on cellulose. The antibacterial durability of the former and the basic properties of cotton fiber products are greatly affected by the antibacterial agents, while the latter usually has complex processes and harsh production conditions. Salicylic acid, as an organic acid, has excellent antibacterial, anti-inflammatory and antioxidant effects and has been widely used in various fields such as medicine. In daily chemical products, it usually acts on the surface of human skin in a dissolving manner, showing temporary effects. Therefore, how to utilize the antibacterial, anti-inflammatory and antioxidant properties of salicylic acid and use it in cotton fibers in order to give cotton fibers long-lasting excellent antibacterial properties, while having good anti-inflammatory, antioxidant effects and biosafety, while not affecting the mechanical properties and wearing properties of cotton fibers, has become a difficult problem that technical personnel in the field of functional fibers need to solve urgently. Summary of the invention

[0006] In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is to provide a method for preparing organic acid-modified antibacterial and antioxidant cotton fibers which have long-lasting excellent antibacterial properties, good anti-inflammatory and antioxidant effects and biological safety.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is: a method for preparing an organic acid-modified antibacterial and antioxidant cotton fiber, comprising the following steps:

[0008] (1) Take a certain amount of cotton fiber and set aside;

[0009] (2) Soak the cotton fiber in a sodium hydroxide aqueous solution for alkalization and react it at 30-40°C for 10-20 minutes to form alcohol anions at the alcohol hydroxyl groups, thereby increasing the reactive centers in the cellulose structure;

[0010] (3) Adjust the temperature to 50-70°C, add 5-chlorosalicylic acid, and carry out etherification reaction for 1-6 hours to remove the halogen and form an ether bond with the alkali cellulose;

[0011] (4) After the reaction is completed, the cotton fibers are taken out for washing and drying;

[0012] (5) Produce organic acid-modified antibacterial and antioxidant cotton fibers.

[0013] In the method for preparing the above-mentioned organic acid-modified antibacterial and antioxidant cotton fibers, in the step (2), the concentration of the sodium hydroxide aqueous solution is 5%-30%, and the reaction is carried out at 35° C. for 15 minutes.

[0014] In the above-mentioned method for preparing the organic acid-modified antibacterial and antioxidant cotton fiber, in the step (3), the etherification reaction temperature is 60° C. and the reaction time is 3 hours.

[0015] In the method for preparing the above-mentioned organic acid-modified antibacterial and antioxidant cotton fiber, in the step (3), the mass ratio of the cotton fiber to 5-chlorosalicylic acid is 1:0.5-4.

[0016] In the above-mentioned method for preparing the organic acid-modified antibacterial and antioxidant cotton fiber, in the step (3), the mass ratio of the cotton fiber to 5-chlorosalicylic acid is 1:2.5.

[0017] In the method for preparing the above-mentioned organic acid-modified antibacterial and antioxidant cotton fibers, in the step (4), the residual solution on the surface of the cotton fibers is washed clean with ethanol and deionized water in sequence, and then the fibers are wrung out and placed in a cool and ventilated place to dry or dried at 40°C.

[0018] The preparation method of the above-mentioned organic acid-modified antibacterial and antioxidant cotton fibers, the cotton fibers include cotton bulk fibers or products containing cotton bulk fibers, specifically including cotton yarn or cotton blended yarn prepared from cotton bulk fibers as raw materials through processes such as carding, pre-drawing, strip winding, drawing, roving, spun yarn, and bobbin winding.

[0019] The preparation method of the organic acid-modified antibacterial and antioxidant cotton fiber of the present invention has the advantages that: the cotton fiber is alkalized in a sodium hydroxide aqueous solution, the alcohol hydroxyl group forms an alcohol anion, the reactive center in the cellulose structure is increased, and then chlorosalicylic acid is added to remove the halogen and form an ether bond with the alkali cellulose to obtain salicylic acid-modified antibacterial cotton fiber. The antibacterial cotton fiber of the present invention is obtained by grafting salicylic acid on the modified fiber surface by means of an etherification reaction under alkaline conditions. The present invention uses a simple and convenient method, a low production cost, and a fast process flow, and utilizes an etherification reaction to graft and modify salicylic acid and the cellulose molecules of the cotton fiber, so that the cotton fiber exhibits an excellent long-term antibacterial effect. While having anti-inflammatory properties, antioxidant properties and biosafety, the fiber still has a smooth and continuous twisted structure after modification, which is similar to the structure of natural cotton fibers, ensuring that the cotton fiber still has ideal mechanical properties and wearing properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the reaction mechanism of salicylic acid modified antibacterial cotton fiber of the present invention;

[0021] Figure 2 The DPPH free radical scavenging rate curve of the modified antibacterial cotton fiber obtained under different salicylic acid dosages;

[0022] Figure 3 It is a comparison chart of the survival rates of L929 cells after one day and three days of culture on the modified antibacterial cotton fiber surface obtained under different salicylic acid dosages;

[0023] Figure 4It is a comparison chart of ELISA test results after culturing macrophages with modified antibacterial cotton fibers obtained under different salicylic acid dosages;

[0024] Figure 5 This is an electron microscope photo of cotton fiber when the mass ratio of cotton fiber to 5-chlorosalicylic acid is 1:1.5;

[0025] Figure 6 This is an electron microscope photo of cotton fiber when the mass ratio of cotton fiber to 5-chlorosalicylic acid is 1:2;

[0026] Figure 7 This is an electron microscope photo of cotton fiber when the mass ratio of cotton fiber to 5-chlorosalicylic acid is 1:2.5;

[0027] Figure 8 This is an electron microscope photograph of cotton fiber when the mass ratio of cotton fiber to 5-chlorosalicylic acid is 1:3. DETAILED DESCRIPTION

[0028] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] In the present invention, unless otherwise stated, directional words such as "upper" and "lower" generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the attached drawings; while "inside" and "outside" refer to the outline of the device. In addition, in the description of this application, the term "including" means "including but not limited to". The terms first, second, third, etc. are used only as labels and do not impose numerical requirements or establish an order. The term "plurality" means "two or more".

[0030] like Figure 1 As shown, a method for preparing an organic acid-modified antibacterial and antioxidant cotton fiber comprises the following steps:

[0031] (1) Take a certain amount of cotton fiber and set aside;

[0032] (2) Soak the cotton fiber in a sodium hydroxide aqueous solution for alkalization and react it at 30-40°C for 10-20 minutes to form alcohol anions at the alcohol hydroxyl groups, thereby increasing the reactive centers in the cellulose structure;

[0033] (3) Adjust the temperature to 50-70°C, add 5-chlorosalicylic acid, and carry out etherification reaction for 1-6 hours to remove the halogen and form an ether bond with the alkali cellulose;

[0034] (4) After the reaction is completed, the cotton fibers are taken out for washing and drying;

[0035] (5) Produce organic acid-modified antibacterial and antioxidant cotton fibers.

[0036] Among them, cotton fibers include cotton bulk fibers or products containing cotton bulk fibers, specifically including cotton yarn or cotton blended yarn prepared with cotton bulk fibers as raw materials through processes such as cleaning and carding, pre-striping, strip winding, drawing, coarse yarn, spun yarn, and bobbin winding.

[0037] The present invention utilizes a one-step grafting modification process to fix salicylic acid in the cellulose macromolecular chain, which can enable the cotton fiber to obtain long-lasting and stable antibacterial, anti-inflammatory and antioxidant functions, while simplifying the process flow, reducing production costs, and ensuring the basic performance of the cotton fiber, laying the foundation for the subsequent development of a series of products.

[0038] The present application is described in detail below through specific embodiments. The following embodiments are only partial embodiments of the present application and are not limitations of the present application.

[0039] Example 1

[0040] A method for preparing organic acid-modified antibacterial and antioxidant cotton fibers comprises the following steps:

[0041] (1) taking a certain amount of cotton fiber for standby use, wherein the cotton fiber includes cotton bulk fiber or products containing cotton bulk fiber, specifically including cotton yarn or cotton blended yarn prepared from cotton bulk fiber as raw material through processes such as blowing and carding, pre-drawing, strip and winding, drawing, roving, spun yarn, and bobbin winding;

[0042] (2) Soak the cotton fiber in a 5% sodium hydroxide aqueous solution for alkalization and react it at 30°C for 20 minutes to form alcohol anions from the alcohol hydroxyl groups, thereby increasing the reactive centers in the cellulose structure;

[0043] (3) adjusting the temperature to 50°C, adding 5-chlorosalicylic acid, and carrying out etherification reaction for 6 hours to remove the halogen and form an ether bond between the cotton fiber and the alkali cellulose; the mass ratio of the cotton fiber to the 5-chlorosalicylic acid is 1:0.5;

[0044] (4) After the reaction is completed, the cotton fiber is taken out for washing and drying; the residual solution on the surface of the cotton fiber is washed clean with ethanol and deionized water in sequence, and then the cotton fiber is placed in a cool and ventilated place to dry or dried at 40°C after being wrung out;

[0045] (5) Produce organic acid-modified antibacterial and antioxidant cotton fibers.

[0046] Example 2

[0047] A method for preparing organic acid-modified antibacterial and antioxidant cotton fibers comprises the following steps:

[0048] (1) taking a certain amount of cotton fiber for standby use, wherein the cotton fiber includes cotton bulk fiber or products containing cotton bulk fiber, specifically including cotton yarn or cotton blended yarn prepared from cotton bulk fiber as raw material through processes such as blowing and carding, pre-drawing, strip and winding, drawing, roving, spun yarn, and bobbin winding;

[0049] (2) Soak the cotton fiber in a 15% sodium hydroxide aqueous solution for alkalization and react it at 35°C for 15 minutes to form alcohol anions from the alcohol hydroxyl groups, thereby increasing the reactive centers in the cellulose structure;

[0050] (3) Adjust the temperature to 60°C, add 5-chlorosalicylic acid, and perform etherification reaction for 3 hours to remove the halogen and form an ether bond with alkali cellulose; the mass ratio of cotton fiber to 5-chlorosalicylic acid is 1:2.5;

[0051] (4) After the reaction is completed, the cotton fiber is taken out for washing and drying; the residual solution on the surface of the cotton fiber is washed clean with ethanol and deionized water in turn, and the cotton fiber is placed in a cool and ventilated place to dry or dried at 40°C after being wrung out.

[0052] (5) Produce organic acid-modified antibacterial and antioxidant cotton fibers.

[0053] Example 3

[0054] A method for preparing organic acid-modified antibacterial and antioxidant cotton fibers comprises the following steps:

[0055] (1) taking a certain amount of cotton fiber for standby use; wherein the cotton fiber includes cotton bulk fiber or products containing cotton bulk fiber, specifically including cotton yarn or cotton blended yarn prepared from cotton bulk fiber as raw material through processes such as blowing and carding, pre-drawing, strip and winding, drawing, roving, spun yarn, and bobbin winding;

[0056] (2) Soak the cotton fiber in a 30% sodium hydroxide aqueous solution for alkalization and react it at 40°C for 10 minutes to form alcohol anions from the alcohol hydroxyl groups, thereby increasing the reactive centers in the cellulose structure;

[0057] (3) Adjust the temperature to 70°C, add 5-chlorosalicylic acid, and perform etherification reaction for 1 hour to remove the halogen and form an ether bond with alkali cellulose; the mass ratio of cotton fiber to 5-chlorosalicylic acid is 1:4;

[0058] (4) After the reaction is completed, the cotton fiber is taken out for washing and drying; the residual solution on the surface of the cotton fiber is washed clean with ethanol and deionized water in sequence, and then the cotton fiber is placed in a cool and ventilated place to dry or dried at 40°C after being wrung out;

[0059] (5) Produce organic acid-modified antibacterial and antioxidant cotton fibers.

[0060] The performance test results of various antibacterial and antioxidant cotton fibers obtained by using different amounts of 5-chlorosalicylic acid under the process conditions of Example 2 of the present invention are as follows:

[0061] 1. Long-lasting antibacterial and washable performance:

[0062] 1. The mass ratio of cotton fiber to 5-chlorosalicylic acid is 1:0.5.

[0063] 10g cotton fiber was soaked in 100mL 15% sodium hydroxide solution, reacted at 35℃ for 15min, then heated to 60℃, 5g 5-chlorosalicylic acid was added, and the reaction was continued for 3h to obtain 5% salicylic acid modified antibacterial cotton fiber. After the reaction, the residual solution on the surface of the cotton fiber was washed clean with ethanol and deionized water in turn, and then wrung out and placed in a cool and ventilated place to dry or dried at 40℃.

[0064] Antibacterial performance test: The antibacterial and washable antibacterial properties of salicylic acid grafted modified antibacterial cotton fibers were tested according to FZ / T 73023-2006. At the same time, the antibacterial cotton fibers of the same batch were stored in a cool and ventilated place, and the antibacterial performance was tested after standing for 6 months and 12 months. The antibacterial rates are shown in Table 1. All samples showed washable and long-lasting antibacterial effects, but the overall antibacterial effect was poor.

[0065] Table 1 Antibacterial effect of 5% salicylic acid modified antibacterial cotton fiber

[0066] Antibacterial rate (%) Escherichia coli Staphylococcus aureus Candida albicans 5% Salicylic Acid 71.4 63.9 61.8 5% Salicylic Acid - After 6 months 70.9 63.0 60.5 5% Salicylic Acid - After 12 months 69.5 61.7 59.4 5% Salicylic Acid - 50 washes 69.8 59.3 60.2 5% Salicylic Acid - 100 washes 68.3 58.6 60.0

[0067] 2. The mass ratio of cotton fiber to 5-chlorosalicylic acid is 1:1.

[0068] 5g 5-chlorosalicylic acid was replaced with 10g 5-chlorosalicylic acid to obtain 10% salicylic acid modified antibacterial cotton fiber, which was tested for antibacterial properties, and the antibacterial rates were shown in Table 2. All samples showed washability and long-lasting antibacterial effects, but the overall antibacterial effect was poor.

[0069] Table 2 Antibacterial effect of 10% salicylic acid modified antibacterial cotton fiber

[0070] Antibacterial rate (%) Escherichia coli Staphylococcus aureus Candida albicans 10% Salicylic Acid 84.0 75.8 73.8 10% Salicylic Acid - After 6 months 81.2 74.6 70.3 10% Salicylic Acid - After 12 months 80.7 73.1 69.1 10% Salicylic Acid - 50 washes 82.8 75.7 71.5 10% Salicylic Acid - 100 washes 81.3 75.6 71.0

[0071] 3. The mass ratio of cotton fiber to 5-chlorosalicylic acid is 1:1.5.

[0072] 5g 5-chlorosalicylic acid was replaced by 15g 5-chlorosalicylic acid to obtain 15% salicylic acid modified antibacterial cotton fiber, which was tested for antibacterial properties. The antibacterial rates were shown in Table 3, and the antibacterial grade reached AAA level of FZ / T73023-2006 standard.

[0073] Table 3 Antibacterial effect of 15% salicylic acid modified antibacterial cotton fiber

[0074]

[0075]

[0076] 4. The mass ratio of cotton fiber to 5-chlorosalicylic acid is 1:2.

[0077] 5g 5-chlorosalicylic acid was replaced by 20g 5-chlorosalicylic acid to obtain 20% salicylic acid modified antibacterial cotton fiber, which was tested for antibacterial properties. The antibacterial rates were shown in Table 4, and the antibacterial level reached AAA level of FZ / T73023-2006 standard.

[0078] Table 4 Antibacterial effect of 20% salicylic acid modified antibacterial cotton fiber

[0079] Antibacterial rate (%) Escherichia coli Staphylococcus aureus Candida albicans 20% Salicylic Acid 98.5 98.0 98.6 20% Salicylic Acid - After 6 months 97.5 97.4 96.8 20% Salicylic Acid - After 12 months 96.2 95.9 95.2 20% Salicylic Acid - 50 washes 98.4 97.2 98.4 20% Salicylic Acid - 100 washes 97.5 97.1 97.4

[0080] 5. The mass ratio of cotton fiber to 5-chlorosalicylic acid is 1:2.5.

[0081] 5g 5-chlorosalicylic acid was replaced by 25g 5-chlorosalicylic acid to obtain 25% salicylic acid modified antibacterial cotton fiber, which was tested for antibacterial properties. The antibacterial rates were shown in Table 5, and the antibacterial grade reached AAA level of FZ / T73023-2006 standard.

[0082] Table 5 Antibacterial effect of 25% salicylic acid modified antibacterial cotton fiber

[0083] Antibacterial rate (%) Escherichia coli Staphylococcus aureus Candida albicans 25% Salicylic Acid ≥99.9 ≥99.9 ≥99.9 25% Salicylic Acid - After 6 months ≥99.9 ≥99.9 ≥99.9 25% Salicylic Acid - After 12 months ≥99.9 ≥99.9 ≥99.9 25% Salicylic Acid - 50 washes ≥99.9 ≥99.9 ≥99.9 25% Salicylic Acid - 100 washes ≥99.9 ≥99.9 ≥99.9

[0084] 6. The mass ratio of cotton fiber to 5-chlorosalicylic acid is 1:3.

[0085] 5g 5-chlorosalicylic acid was replaced by 30g 5-chlorosalicylic acid to obtain 30% salicylic acid modified antibacterial cotton fiber, which was tested for antibacterial properties. The antibacterial rates were shown in Table 6, and the antibacterial level reached AAA level of FZ / T73023-2006 standard.

[0086] Table 6 Antibacterial effect of 30% salicylic acid modified antibacterial cotton fiber

[0087] Antibacterial rate (%) Escherichia coli Staphylococcus aureus Candida albicans 30% Salicylic Acid ≥99.9 ≥99.9 ≥99.9 30% Salicylic Acid - After 6 months ≥99.9 ≥99.9 ≥99.9 30% Salicylic Acid - After 12 months ≥99.9 ≥99.9 ≥99.9 30% Salicylic Acid - 50 washes ≥99.9 ≥99.9 ≥99.9 30% Salicylic Acid - 100 washes ≥99.9 ≥99.9 ≥99.9

[0088] 7. The mass ratio of cotton fiber to 5-chlorosalicylic acid is 1:3.5.

[0089] 5g 5-chlorosalicylic acid was replaced with 35g 5-chlorosalicylic acid to obtain 35% salicylic acid modified antibacterial cotton fiber, which was tested for antibacterial properties. The antibacterial rates were shown in Table 7, and the antibacterial grade reached AAA level according to FZ / T73023-2006 standard.

[0090] Table 7 Antibacterial effect of 35% salicylic acid modified antibacterial cotton fiber

[0091] Antibacterial rate (%) Escherichia coli Staphylococcus aureus Candida albicans 35% Salicylic Acid ≥99.9 ≥99.9 ≥99.9 35% Salicylic Acid - After 6 months ≥99.9 ≥99.9 ≥99.9 35% Salicylic Acid - After 12 months ≥99.9 ≥99.9 ≥99.9 35% Salicylic Acid - 50 washes ≥99.9 ≥99.9 ≥99.9 35% Salicylic Acid - 100 washes ≥99.9 ≥99.9 ≥99.9

[0092] 8. The mass ratio of cotton fiber to 5-chlorosalicylic acid is 1:4.

[0093] 5g 5-chlorosalicylic acid was replaced by 40g 5-chlorosalicylic acid to obtain 40% salicylic acid modified antibacterial cotton fiber, which was tested for antibacterial properties. The antibacterial rate was shown in Table 8, and the antibacterial level reached AAA level of FZ / T73023-2006 standard.

[0094] Table 8 Antibacterial effect of 40% salicylic acid modified antibacterial cotton fiber

[0095] Antibacterial rate (%) Escherichia coli Staphylococcus aureus Candida albicans 40% Salicylic Acid ≥99.9 ≥99.9 ≥99.9 40% Salicylic Acid - After 6 months ≥99.9 ≥99.9 ≥99.9 40% Salicylic Acid - After 12 months ≥99.9 ≥99.9 ≥99.9 40% Salicylic Acid - 50 washes ≥99.9 ≥99.9 ≥99.9 40% Salicylic Acid - 100 washes ≥99.9 ≥99.9 ≥99.9

[0096] 2. Antioxidant properties:

[0097] Prepare 0.1mM DPPH methanol solution, weigh 1.875mg, 3.75mg, 7.5mg, 15mg and 30mg of 5% salicylic acid modified antibacterial cotton fiber, 10% salicylic acid modified antibacterial cotton fiber, 15% salicylic acid modified antibacterial cotton fiber, 20% salicylic acid modified antibacterial cotton fiber, 25% salicylic acid modified antibacterial cotton fiber, 30% salicylic acid modified antibacterial cotton fiber, 35% salicylic acid modified antibacterial cotton fiber, 40% salicylic acid modified antibacterial cotton fiber, add to 3mL DPPH solution, set 3mL DPPH solution as blank control, soak in light at room temperature for 30min, read the absorbance at 517nm, and calculate the scavenging rate of the sample for DPPH free radicals using the following formula.

[0098]

[0099] A0 is the average absorbance of the control group, A e is the average absorbance measured in the experimental group, and the DPPH removal rate of each gradient leaching solution is calculated as follows: Figure 2 As shown. The cotton fiber grafted with low concentration salicylic acid has almost no antioxidant effect. As the concentration of salicylic acid grafting increases, the DPPH removal effect is significantly improved, and as the fiber soaking concentration increases, the DPPH removal rate gradually increases. The DPPH removal rate of the antibacterial cotton fiber modified with 40% salicylic acid at 30 mg / mL reaches a maximum of 84.7±6.8%. It can be seen that the cotton fiber prepared by the present invention has ideal antioxidant properties.

[0100] 3. Cytotoxicity test:

[0101] Referring to the cytotoxicity test method of GBT 16886.5-2017, various antibacterial cotton fibers were made into a 20g / m2 The spunlace fabric was cut into discs with a diameter of 1 cm. After high-pressure sterilization, cells were evenly seeded on the sample surface and cultured for three consecutive days for in vitro cytotoxicity test. The cell survival rate was calculated according to the following formula.

[0102]

[0103] Among them A e is the average absorbance measured in the experimental group, A0 is the average absorbance measured in the control group on the first day, and the cell survival rate is calculated as Figure 3 As shown. Figure 3 It can be seen that all concentrations of salicylic acid-modified cotton fibers have good cell compatibility. When co-cultured with fibroblasts for 1 day, the cell survival rate is higher than 98%. When co-cultured for 3 days, the cell survival rate decreases slightly, but is still higher than 92%. It can be seen that the cotton fiber of the present invention has excellent biological safety.

[0104] 4. Anti-inflammatory performance test

[0105] Various antibacterial cotton fibers are made into a gram weight of 20g / m 2 The spunlace fabric was cut into 1 cm diameter discs and sterilized by high pressure. 5 The cells were uniformly seeded on the cotton fibers at a density of 10 cells / cell. After 72 hours of culture, the culture medium was taken for ELISA test to characterize the secretion levels of pro-inflammatory factors interleukin-6 (IL-6), tumor necrosis factor (TNF-α) and anti-inflammatory factors interleukin-10 (IL-10) and interleukin-13 (IL-13). The blank control group was set as a sample of ordinary cotton fiber spunlace cloth with the same gram weight, and the concentrations of various inflammatory factors were obtained. Figure 4 As shown. The secretion levels of various inflammatory factors were similar in the ordinary cotton fiber, 5% salicylic acid modified cotton fiber, 10% salicylic acid modified cotton fiber, and 15% salicylic acid modified cotton fiber groups. When the salicylic acid concentration reached 20% or above, the concentrations of pro-inflammatory factors TNF-α and IL-6 decreased rapidly, and the concentrations of anti-inflammatory factors IL-10 and IL-13 increased rapidly, and the anti-inflammatory performance was significantly enhanced. This shows that when the concentration of salicylic acid grafting reaches the critical value of 20%, the modified cotton fiber begins to show good anti-inflammatory effects, and as the concentration of salicylic acid is further increased, the anti-inflammatory ability is also slightly enhanced.

[0106] The performance test results show that:

[0107] The salicylic acid modified antibacterial cotton fiber provided by the present invention can show long-lasting excellent antibacterial performance on the basis of maintaining the inherent morphology and structure, and has good anti-inflammatory and antioxidant effects and biological safety. Through comparative analysis, the addition amount of 5-chlorosalicylic acid has a significant effect on the antibacterial, anti-inflammatory and antioxidant properties. As the addition ratio of 5-chlorosalicylic acid increases, the antibacterial, anti-inflammatory and antioxidant effects of the modified cotton fiber are enhanced, and the mass ratio of cotton fiber to 5-chlorosalicylic acid is at least 1:2.5.

[0108] The surface morphology of the modified antibacterial cotton fiber obtained when the ratio of cotton fiber to salicylic acid addition was 1:1.5-3 was as follows: Figure 5-8 As shown in the figure, it can be clearly seen that the fiber still has a smooth and continuous twisted structure after modification, which is similar to the structure of untreated natural cotton fibers. It can be concluded that the modified cotton fiber guarantees basic mechanical properties, machinability and wearing performance. The salicylic acid modified antibacterial cotton fiber provided by the present invention can show long-lasting excellent antibacterial properties on the basis of maintaining the inherent morphology and structure, and has good anti-inflammatory, antioxidant effects and biological safety.

[0109] The invention is based on the fact that after the cotton fiber is alkalized, alcohol hydroxyl groups form alcohol anions, so that the cellulose has more reactive active groups for subsequent etherification reaction, the degree of substitution increases, and 5-chlorosalicylic acid forms an ether bond with alkali cellulose in an alkaline environment to obtain salicylic acid-modified antibacterial cotton fiber. The cellulose and salicylic acid in the cotton fiber are connected by ether bonds to establish a stable molecular structure. The modified cotton fiber has excellent antibacterial effect, is washable, and can achieve long-term antibacterial; the surface morphology does not change significantly; it has certain antioxidant properties; it has excellent biocompatibility; and it exhibits certain anti-inflammatory effects. By establishing an ether bond between cellulose and salicylic acid, a functional cotton fiber with a stable structure and firmness is obtained, so that its antibacterial, antimicrobial and antioxidant properties remain long-lasting and effective. The production process is short, the process is convenient, and mass production can be achieved.

[0110] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Any changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention should fall within the protection scope of the present invention.

Claims

1. A method for preparing an organic acid-modified antibacterial and antioxidant cotton fiber, characterized in that: The steps include: (1) Take a certain amount of cotton fiber and set aside; (2) Soak the cotton fiber in a sodium hydroxide aqueous solution for alkalization and react it at 30-40°C for 10-20 minutes to form alcohol anions at the alcohol hydroxyl groups, thereby increasing the reactive centers in the cellulose structure; (3) Adjust the temperature to 50-70°C, add 5-chlorosalicylic acid, and carry out etherification reaction for 1-6 hours to remove the halogen and form an ether bond with the alkali cellulose; (4) After the reaction is completed, the cotton fibers are taken out for washing and drying; (5) Produce organic acid-modified antibacterial and antioxidant cotton fibers.

2. The method for preparing the organic acid-modified antibacterial and antioxidant cotton fiber according to claim 1, characterized in that: In the step (2), the concentration of the sodium hydroxide aqueous solution is 5%-30%, and the reaction is carried out at 35° C. for 15 minutes.

3. The method for preparing the organic acid-modified antibacterial and antioxidant cotton fiber according to claim 1, characterized in that: In the step (3), the etherification reaction temperature is 60° C. and the reaction time is 3 h.

4. The method for preparing the organic acid-modified antibacterial and antioxidant cotton fiber according to claim 1, characterized in that: In the step (3), the mass ratio of cotton fiber to 5-chlorosalicylic acid is 1:0.5-4.

5. The method for preparing the organic acid-modified antibacterial and antioxidant cotton fiber according to claim 1, characterized in that: In the step (3), the mass ratio of cotton fiber to 5-chlorosalicylic acid is 1:2.

5.

6. The method for preparing the organic acid-modified antibacterial and antioxidant cotton fiber according to claim 1, characterized in that: In the step (4), the residual solution on the surface of the cotton fiber is washed clean with ethanol and deionized water in sequence, and then placed in a cool and ventilated place to dry or dried at 40°C after being wrung out.

7. The method for preparing the organic acid-modified antibacterial and antioxidant cotton fiber according to claim 1, characterized in that: The cotton fibers include cotton bulk fibers or products containing cotton bulk fibers, specifically cotton yarn or cotton blended yarn prepared from cotton bulk fibers as raw materials through processes such as blowing and carding, pre-drawing, strip winding, drawing, roving, spun yarn, and bobbin winding.

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