Method for preparing modified fiber from plant extract and modified fiber

Abstract

The invention provides a method for preparing a modified fiber from a plant extract and the modified fiber. The method comprises the following steps: S1, obtaining a sugar-free plant extract; the main group of the plant extract contains one or two of phenolic hydroxyl and hydroxyl; s2, pretreating the plant extract and the copolymer to obtain a prepolymer mixture; the group of the copolymer can be subjected to prepolymerization reaction with the phenolic hydroxyl group and / or hydroxyl group in the plant extract, and can also be subjected to chemical reaction with the functional group in the fiber spinning solution; and S3, carrying out wet spinning on the prepolymer mixture and a fiber spinning solution to obtain the modified fiber. According to the invention, the plant extract firstly reacts with the copolymer, and then the reacted polymer reacts with the group in the spinning solution, so that chemical connection exists between the plant extract and the fiber, and the overall strength of the fiber is improved; the fiber not only has better antibacterial property, but also keeps lasting antibacterial property after being washed for multiple times.

Description

Technical Field

[0001] The present invention relates to the field of functional fiber preparation, and in particular to a method for preparing modified fiber by using plant extracts and the modified fiber. Background Art

[0002] In the extraction of beneficial ingredients from plants, in addition to polysaccharides, the core beneficial ingredients basically contain phenolic hydroxyl, hydroxyl and carboxyl groups. Such as tea polyphenols in tea, ginsenosides in ginseng, triterpenes, polyphenols, ganoderic acid in ganoderma lucidum, saponins, flavonoids, organic acids in Panax notoginseng, etc. However, with the improvement of people's living standards, in addition to the comfort, beauty, economy and durability required by traditional textiles, people often put forward higher requirements for the functionality of existing fibers, such as antibacterial, antistatic, anti-pilling and anti-fouling, etc.; especially now, people's daily life has more and more demands for antibacterial and antiviral, and the requirements are getting higher and higher.

[0003] Plant extracts contain a variety of active ingredients, such as alkaloids, flavonoids, polyphenols, terpenes, etc. These ingredients have multiple biological activities such as antibacterial, antiviral, and antioxidant. Plant extracts have natural advantages and are generally welcomed by people; however, in the prior art, in the wet spinning process, the plant extract is usually directly blended with the spinning solution and then spun. There is no chemical connection between the plant extract and the fiber. After the spun fiber is washed many times, the plant extract is easily separated from the fiber, which reduces the antibacterial property of the fiber.

[0004] The invention patent application with Chinese patent number CN 110592713 B discloses a method for preparing antibacterial polyacrylonitrile fiber, in which plant extracts are blended with spinning solution and then the spun fiber is treated with a copper ion solution to complex the hydroxyl groups in natural cellulose with copper ions. However, copper ions are heavy metal ions. For some people with sensitive skin, long-term contact with copper ion fibers may cause skin irritation or allergic reactions, such as redness, itching, pain, etc.

[0005] The invention patent application with Chinese patent number CN105803673B discloses a tea polyphenol cellulose fiber spunlace non-woven fabric and its production process. The non-woven fabric adds naturally extracted nano-grade tea polyphenols and inorganic salt composite antibacterial agents into the fiber web during the production of the spunlace non-woven fabric to form a product with high efficiency in moisture absorption, sweat conduction, antibacterial, anti-allergic and anti-inflammatory properties. The prior art only attaches tea polyphenols to cellulose, and there is no chemical connection between the fiber and the tea polyphenols. During use, the tea polyphenols are easy to fall off, the antioxidant and antibacterial stability are not high, the product shelf life is short, and the process flow is long, the production process is complicated, and the production cost is high. Summary of the invention

[0006] In view of this, the present invention aims to provide a method for preparing modified fibers by plant extracts and modified fibers, so as to solve the problem that in the prior art, in the wet spinning process, plant extracts are usually directly mixed with spinning liquid and then spun, there is no chemical connection between the plant extracts and the fibers, and the plant extracts are easily separated from the fibers after multiple washings, resulting in a decrease in the functionality of the fibers.

[0007] To achieve the above object, the technical solution of the present invention is achieved as follows: A method for preparing modified fiber by using plant extracts comprises the following steps: S1. Obtaining a sugar-free plant extract; wherein the main groups of the plant extract contain one or two of phenolic hydroxyl group and hydroxyl group; S2, pre-treating the plant extract and the copolymer to obtain a prepolymer mixture; the groups of the copolymer can undergo a prepolymerization reaction with the phenolic hydroxyl group and / or hydroxyl group in the plant extract, and can also undergo a chemical reaction with the functional groups in the fiber spinning solution; S3. Wet spinning the prepolymer mixture and the fiber spinning solution to obtain modified fibers.

[0008] This setting allows the plant extract to react with the copolymer first, and then chemically reacts the reacted polymer with the groups in the spinning solution, so that there is a chemical connection between the plant extract and the fiber, which not only improves the overall strength of the fiber; the fiber not only has good antibacterial properties, but also after multiple washings, the plant extract is not easy to separate from the fiber, thereby improving the fiber's lasting antibacterial properties.

[0009] Furthermore, the copolymer is one or both of an acrylic ester copolymer and a maleic anhydride grafted polymer.

[0010] When the copolymer is an acrylic copolymer, the copolymer (such as methyl acrylate, butyl acrylate, etc.) contains active double bonds, which can react with phenolic hydroxyl and hydroxyl groups in plant extracts through free radical polymerization to generate ester bonds or ether bonds. These copolymers can also be grafted with wet spinning solutions (such as hydroxyl groups of viscose fibers) to enhance the mechanical strength and functionality of the fibers.

[0011] When the copolymer is a maleic anhydride grafted polymer, the anhydride group in the maleic anhydride grafted polymer undergoes a ring-opening reaction with the phenolic hydroxyl group or hydroxyl group in the plant extract to generate an ester bond or anhydride group. Maleic anhydride reacts with the hydroxyl, amino or carboxyl group in the wet spinning solution, such as the hydroxyl group in viscose fiber, or the nitrile group in acrylic fiber is converted into an amide group, and the thermal stability and chemical resistance of the fiber are improved through graft copolymerization.

[0012] Furthermore, the plant extract is a plant leaf bark extract and rhizome extract, including one or more of tea extract, mulberry leaf extract, bamboo leaf extract, anthocyanin extract, paclitaxel extract, ginseng extract, ganoderma lucidum extract, dendrobium extract, and Panax notoginseng extract.

[0013] Furthermore, the modified fiber is one of viscose-based fiber, acrylic fiber, acetate fiber, cuprammonium fiber, seaweed fiber, and chitin fiber.

[0014] When the modified fiber is viscose-based fiber, the cellulose molecules of viscose-based fiber contain a large number of hydroxyl groups (-OH), so they can form stable ester bonds or ether bonds through ester exchange with ester groups (-COOR) in the copolymer, or copolymerization with anhydride groups in the copolymer. These reactions help to improve the functionality and durability of viscose fibers.

[0015] When the modified fiber is acrylic fiber, in the acrylic spinning solution, part of the nitrile group is converted into an amide group by reacting with an amine compound (such as ethylenediamine), thereby providing active sites for graft copolymerization. The generated amide group can further transesterify with the ester group (-COOR) in the copolymer and react with the anhydride pre-copolymer to form a stable graft structure.

[0016] When the modified fiber is acetate fiber, the main component of acetate fiber is cellulose acetate, which contains ester groups (-COOR). The ester groups can undergo ester exchange reactions with hydroxyl groups (-OH) in the copolymer, or copolymerize with anhydride groups. Due to the low reactivity of the ester groups, catalysts or specific conditions are generally required for effective copolymerization reactions to occur.

[0017] When the modified fiber is cuprammonium fiber, cuprammonium fiber is made of cellulose, and the cellulose molecule contains a large number of hydroxyl groups, so similar to viscose fiber, it can react with the ester group and anhydride group in the copolymer. The reactivity of the hydroxyl group makes cuprammonium fiber very effective when grafting or functionalizing.

[0018] When the modified fiber is seaweed fiber, the seaweed fiber is mainly composed of sodium alginate, which contains carboxyl and hydroxyl groups. The carboxyl group can undergo esterification or addition reaction with the anhydride group in the copolymer to form a stable covalent bond. In addition, the hydroxyl group can also react with the ester group and anhydride group in the copolymer.

[0019] When the modified fiber is chitin fiber, chitin fiber contains amino and hydroxyl groups. The amino group can react with aldehyde crosslinking agents (such as glutaraldehyde and formaldehyde) to undergo imidization reaction, and react with anhydride groups to undergo addition or esterification reaction. The hydroxyl group can also react with ester groups and anhydride groups, so that the chitin fiber has good reactivity during the functionalization and modification process.

[0020] Furthermore, the viscose-based fiber is one or more of viscose, modal, tencel, bamboo fiber, and lyocell.

[0021] Furthermore, when the modified fiber is acrylic fiber and the plant extract is tea polyphenols, the specific method is as follows: Step 1: dissolving tea polyphenols in N,N-dimethylacetamide, adding polyvinyl pyrrolidone and MOFS, stirring and dissolving to obtain a tea polyphenol mixed solution; the setting improves the dispersibility of tea polyphenols and increases the contact area between tea polyphenols and the copolymer by adding polyvinyl pyrrolidone; MOFS catalyzes the reaction between the hydroxyl group of tea polyphenols and the anhydride group of styrene-maleic anhydride in step 2; Step 2: dissolving the styrene-maleic anhydride copolymer in N,N-dimethylacetamide, and then adding the tea polyphenols mixed solution, stirring to fully mix, heating the temperature to 60-80°C, and maintaining the time for 3-5 hours. After the reaction is completed, purifying to obtain a prepolymer. This setting allows the styrene-maleic anhydride copolymer and the tea polyphenols mixed solution to fully react; Step three: adding ethylenediamine and potassium persulfate to the polyacrylonitrile spinning solution, the reaction temperature is 60-70°C, the reaction time is 3-5h, and a modified spinning solution is obtained; this setting adds ethylenediamine and potassium persulfate to the polyacrylonitrile spinning solution, so that the polyacrylonitrile undergoes sufficient amide group modification, and the generated amide group can further react with the prepolymer, thereby firmly fixing the plant extract on the fiber.

[0022] Step 4: Add prepolymer to the modified spinning solution, disperse it evenly, and then perform wet spinning to obtain modified fibers.

[0023] Furthermore, in step 1, the weight ratio of the tea polyphenols, polyvinyl pyrrolidone, MOFS, and N,N-dimethylacetamide is (3-7): (0.2-0.4): (0.4-0.6): (70-120).

[0024] Furthermore, in step 2, the weight ratio of the styrene-maleic anhydride copolymer to N,N-dimethylacetamide is (7-9): (10-100).

[0025] Furthermore, in step 2, the purification refers to first precipitation or membrane filtration and then drying.

[0026] Furthermore, in step three, the weight ratio of ethylenediamine, potassium persulfate and polyacrylonitrile spinning solution is (8-12): (1-3): (80-120).

[0027] Furthermore, the spinning solution is obtained by dissolving polyacrylonitrile in dimethyl sulfoxide, wherein the mass percentage of polyacrylonitrile in the polyacrylonitrile spinning solution is 20% to 40%.

[0028] Furthermore, in step 4, the weight ratio of the prepolymer to the spinning solution is (1-5): (10-100).

[0029] Furthermore, when the plant extract is tea polyphenols and the modified fiber is viscose fiber, the specific method is as follows: Step 1: dissolving tea polyphenol powder in an ethanol aqueous solution, adding polyacrylate, and evenly dispersing to obtain a tea polyphenol mixed solution, and then adding it to a dilute toluenesulfonic acid solution, reacting for 2 to 3 hours, to obtain a tea polyphenol treated solution, wherein the dilute toluenesulfonic acid solution is a mixture of p-toluenesulfonic acid and an ethanol aqueous solution; this setting is to promote the activation of phenolic hydroxyl groups and hydroxyl groups in tea polyphenols; Step 2: dissolving β-hydroxyethyl acrylate in an ethanol aqueous solution, then adding 1-ethyl-(3-dimethylaminopropyl) carbodiimide and polyethylene glycol N-hydroxysuccinimide ester in a certain ratio, reacting for 2-3 hours to obtain an activated cross-linking solution; the activated cross-linking solution can promote the reaction between the ester group of polyacrylate and the hydroxyl group of tea polyphenols; Step 3: Mix the tea polyphenol treatment solution and the activated cross-linking solution, react for 2-3 hours, then add an alkaline solution to adjust the pH, and control the pH between 5 and 7, then add MOFS, stir for 2-4 hours, and purify to obtain a prepolymer; This setting allows the tea polyphenols to react with the polyacrylate while the obtained prepolymer can also copolymerize with the groups of the viscose fiber, so that the plant extract is firmly fixed on the fiber; Step 4: Add the prepolymer to the viscose spinning solution and obtain the modified fiber by wet spinning.

[0030] Furthermore, the ethanol aqueous solution in step 1, step 2 and step 3 is a mixture of ethanol and water, wherein the weight ratio of ethanol to water is (50-70): (30-50).

[0031] Furthermore, when preparing the dilute toluenesulfonic acid solution, the weight ratio of p-toluenesulfonic acid to ethanol aqueous solution is (0.2-0.4): (70-120).

[0032] Furthermore, when the dilute toluenesulfonic acid solution is mixed with the tea polyphenols mixed solution, the weight ratio between the two is 1:1.

[0033] Furthermore, in step 1, the weight ratio of the tea polyphenol powder, ethanol aqueous solution, polyacrylate, and toluenesulfonic acid dilute solution is (3-7): (80-120): (0.2-0.4): (0.2-0.4).

[0034] Furthermore, in step 2, the weight ratio of β-hydroxyethyl acrylate, 1-ethyl-(3-dimethylaminopropyl)carbodiimide, polyethylene glycol N-hydroxysuccinimide ester, and ethanol aqueous solution is (6-10): (0.1-0.3): (0.1-0.2): (70-120).

[0035] Furthermore, in step three, the MOFS accounts for 0.4-0.6% of the weight of the mixed solution.

[0036] Furthermore, in step 4, the solid content is controlled at 35-45%.

[0037] Furthermore, when the plant extract is ginsenoside and the modified fiber is cellulose acetate, the specific method is as follows: Step 1: dissolve ginseng soap and methacrylic acid-maleic anhydride in N,N-dimethylacetamide, add p-toluenesulfonic acid solution, heat to 60-70°C, react for 2-3h, and purify to obtain a prepolymer; Step 2: Add the prepolymer to the acetate spinning solution, add MOFS at the same time, and wet spin to obtain acetate fiber.

[0038] In this setting, methacrylic acid-maleic anhydride contains active anhydride groups, which undergo esterification reaction with the hydroxyl groups in ginseng soap to generate a prepolymer. The prepolymer contains anhydride groups. The main component of acetate fiber is cellulose acetate, which contains ester groups (-COOR). The ester groups and anhydride groups undergo copolymerization reaction, making the ginseng soap more firmly present in the fiber.

[0039] Furthermore, the weight ratio of the ginsenoside, methacrylic acid-maleic anhydride, and N,N-dimethylacetamide is (4-7): (6-10): (70-120).

[0040] Furthermore, the MOFS catalyst accounts for 0.3-0.7% of the total weight of the prepolymer and the acetate spinning solution.

[0041] Furthermore, the prepolymer accounts for 35-45% of the total weight of the acetate spinning solution.

[0042] Furthermore, in the preparation of acrylic fiber, viscose fiber and acetate fiber, the MOFS catalyst is one or more of iron-based MOFS, titanium-based MOFS or zinc-based MOFS.

[0043] Compared with the prior art, the method for preparing modified fiber by using plant extracts according to the present invention has the following advantages: 1) The present invention first grafts the plant extract with the copolymer, and then reacts the grafted polymer with the group in the spinning solution, so that there is a chemical connection between the plant extract and the fiber, which not only improves the overall strength of the fiber; the fiber not only has good antibacterial properties, but also after multiple washings, the plant extract is not easy to separate from the fiber, thereby improving the durable antibacterial properties of the fiber.

[0044] The present invention also provides a modified fiber, comprising the above-mentioned preparation method.

[0045] The modified fiber has the same advantages as the above-mentioned method for preparing modified fiber by plant extracts over the prior art, which will not be described in detail here. DETAILED DESCRIPTION

[0046] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below. Example 1

[0047] The modified fiber prepared in this embodiment is acrylic fiber, wherein the parts in the embodiment are calculated by weight, solid content = weight of prepolymer / weight of spinning solution, and the following method is used: (1) taking tea polyphenol powder with a purity of ≥90w% and a particle size passing through a sieve of 80-100 mesh, dissolving 5 parts of tea polyphenol powder in 100 parts of N,N-dimethylacetamide (DMAC), adding 0.2 parts of polyvinyl pyrrolidone (PVP) and 0.5 parts of iron-based MOF, stirring and uniformly dissolving the mixture to prepare a tea polyphenol mixture; (2) 8 parts of styrene-maleic anhydride copolymer (SMA) were dissolved in 50 parts of DMAC to obtain an SMA solution after it was fully dissolved. The tea polyphenol mixture was mixed with the SMA solution, stirred to fully mix, and then heated to 70°C for 4 hours. After the reaction was completed, the unreacted maleic anhydride grafted polymer and free reaction substances were removed according to a conventional solvent precipitation method to obtain a purified prepolymer; (3) dissolving 20 parts of polyacrylonitrile in 80 parts of dimethyl sulfoxide to obtain a polyacrylonitrile spinning solution, then adding 10 parts of ethylenediamine and 1.5 parts of potassium persulfate to the polyacrylonitrile spinning solution, heating to 65° C., and maintaining for 3 hours to obtain a modified spinning solution; (4) Add the prepolymer to the modified spinning solution, control the solid content to 35%, stir and mix thoroughly, disperse evenly, let stand, degas, filter, and then spin according to the conventional wet spinning process. The process is as follows: feed the spinning solution - spinneret spinning - coagulation bath coagulation - stretching - washing - oiling - drying, qualitative - curling - cutting - packaging, and then the modified fiber is obtained. Example 2

[0048] The modified fiber prepared in this embodiment is acrylic fiber. The parts in the embodiment are calculated by weight, solid content = prepolymer / spinning solution, and the following method is used: (1) Take tea polyphenol powder with a purity of ≥90w% and a particle size passing through a sieve of 80-100 meshes, dissolve 5 parts of tea polyphenol powder in 100 parts of N,N-dimethylacetamide (DMAC), add 0.2 parts of polyvinyl pyrrolidone (PVP) and 0.4 parts of iron-based MOF, stir and uniformly dissolve to prepare a tea polyphenol mixture; (2) Dissolving 7 parts of styrene-maleic anhydride copolymer (SMA) in 50 parts of DMAC to obtain an SMA solution after sufficient dissolution, mixing the tea polyphenol mixture with the SMA solution, stirring to fully mix, and then heating to 60°C for 5 hours. After the reaction is completed, removing the unreacted maleic anhydride grafted polymer and free reaction substances according to a conventional solvent precipitation method to obtain a purified prepolymer; (3) dissolving 30 parts of polyacrylonitrile in 70 parts of dimethyl sulfoxide to obtain a polyacrylonitrile spinning solution, then adding 9 parts of ethylenediamine and 1 part of potassium persulfate to the polyacrylonitrile spinning solution, heating to 65° C. and maintaining for 4 hours to obtain a modified spinning solution; (4) Add the prepolymer to the modified spinning solution, control the solid content to 35%, stir and mix thoroughly, disperse evenly, let stand, degas, filter, and then spin according to the conventional wet spinning process. The process is as follows: feed the spinning solution - spinneret spinning - coagulation bath coagulation - stretching - washing - oiling - drying, qualitative - curling - cutting - packaging, and then the modified fiber is obtained. Example 3

[0049] The modified fiber prepared in this embodiment is acrylic fiber. The parts in the embodiment are calculated by weight, solid content = prepolymer / spinning solution, and the following method is used: (1) Take tea polyphenol powder with a purity of ≥90w% and a particle size passing through a sieve of 80-100 meshes, dissolve 5 parts of tea polyphenol powder in 100 parts of N,N-dimethylacetamide (DMAC), add 0.4 parts of polyvinyl pyrrolidone (PVP) and 0.6 parts of iron-based MOF, stir and uniformly dissolve to prepare a tea polyphenol mixture; (2) dissolving 9 parts of styrene-maleic anhydride copolymer (SMA) in 50 parts of DMAC to obtain an SMA solution after sufficient dissolution, mixing the tea polyphenol mixture with the SMA solution, stirring to fully mix, and then heating to 80°C for 3 hours. After the reaction is completed, removing the unreacted maleic anhydride grafted polymer and free reaction substances according to a conventional solvent precipitation method to obtain a purified prepolymer; (3) dissolving 40 parts of polyacrylonitrile in 60 parts of dimethyl sulfoxide to obtain a polyacrylonitrile spinning solution, then adding 11 parts of ethylenediamine and 2 parts of potassium persulfate to the polyacrylonitrile spinning solution, heating to 65° C. and maintaining for 5 hours to obtain a modified spinning solution; (4) Add the prepolymer to the modified spinning solution, control the solid content to 35%, stir and mix thoroughly, disperse evenly, let stand, degas, filter, and then spin according to the conventional wet spinning process. The process is as follows: feed the spinning solution - spinneret spinning - coagulation bath coagulation - stretching - washing - oiling - drying, qualitative - curling - cutting - packaging, and then the modified fiber is obtained.

[0050] Comparative Example 1 The difference between this comparative example and Example 1 is that in step (3), ethylenediamine and 2 g of potassium persulfate are not added to the polyacrylonitrile spinning solution.

[0051] Comparative Example 2 The difference between this comparative example and Example 2 is that the tea polyphenol in step (1) is directly added to the polyacrylonitrile spinning solution, which is obtained by dissolving 40 parts of polyacrylonitrile in 60 parts of dimethyl sulfoxide. The weight ratio of tea polyphenol to polyacrylonitrile spinning solution is 5:100.

[0052] The tea polyphenols in Examples 1-3 and Comparative Examples 1-2 include catechins, which account for 70% of the tea polyphenols. Corresponding parameter tests were performed on the fibers obtained in Examples 1-3 and Comparative Examples 1-2, and the specific parameters after taking the average values ​​of multiple tests are shown in Table 1.

[0053] Table 1

[0054] By comparing Examples 1 to 3 with Comparative Example 1 and Comparative Document 2, it can be seen that the fiber prepared by the method of the present invention has a high catechin content, and the fiber has good strength, and especially exhibits good antibacterial and long-lasting antibacterial properties. Example 4

[0055] The modified fiber prepared in this embodiment is viscose fiber, wherein the viscose spinning solution (cellulose content 8.9%) used in the embodiment is purchased from Shandong Yinying Chemical Fiber Co., Ltd.; the ethanol solubility in the ethanol aqueous solution mentioned in the embodiment is 50%; the parts in the embodiment are calculated according to weight parts, solid content = prepolymer / spinning solution.

[0056] Use the following method: (1) Take tea polyphenol powder with a purity of ≥90w% and a particle size passing through a sieve of 80-100 meshes, dissolve 5 parts of tea polyphenol powder in 100 parts of ethanol aqueous solution, add 0.25 parts of polyacrylate, and evenly disperse to obtain a tea polyphenol mixed solution, then prepare a dilute p-toluenesulfonic acid solution, use 0.25 parts of p-toluenesulfonic acid and 100 parts of ethanol aqueous solution, add the tea polyphenol mixed solution to the dilute p-toluenesulfonic acid solution, the weight ratio is 1:1, and react for 2 hours to promote the activation of phenolic hydroxyl and hydroxyl groups in tea polyphenols, and obtain a tea polyphenol treated solution; (2) Dissolve 7 parts of β-hydroxyethyl acrylate (HEA) in 100 parts of ethanol solution, then add 0.15 parts of 1-ethyl-(3-dimethylaminopropyl)carbodiimide and 0.15 parts of polyethylene glycol N-hydroxysuccinimide ester, and react for 2 hours to obtain an activated cross-linking solution; (3) Mixing the tea polyphenol treatment solution and the activated cross-linking solution in a weight ratio of 1:1, reacting for 2 hours, then adding a sodium hydroxide solution to adjust the pH, wherein the concentration of sodium hydroxide is 1%, so that the pH of the mixed solution is maintained at 6, and then adding an iron-based MOF, wherein the weight ratio of the iron-based MOF to the total mixed solution is 0.4:100, stirring for 3 hours, and purifying to obtain a prepolymer. The purification adopts a conventional membrane filtration method, which is not described in detail here; (4) Add the prepolymer to the viscose spinning solution and control the solid content to 35%. After being fully stirred and mixed, the solution is evenly dispersed, left to stand, degassed, filtered, and then spun according to the conventional wet spinning process. The process is as follows: feeding the spinning solution - spinning the spinneret - coagulation in a coagulation bath - stretching - washing - oiling - drying, characterization - curling - cutting - packaging to obtain the modified fiber. Example 5

[0057] The modified fiber prepared in this embodiment is viscose fiber, wherein the viscose spinning solution (cellulose content 8.9%) used in the embodiment is purchased from Shandong Yinying Chemical Fiber Co., Ltd.; the ethanol solubility in the ethanol aqueous solution mentioned in the embodiment is 70%; the parts in the embodiment are all calculated according to weight parts, solid content = prepolymer weight / spinning solution weight.

[0058] Use the following method: (1) Take tea polyphenol powder with a purity of ≥90w% and a particle size passing through a sieve of 80-100 meshes, dissolve 5 parts of tea polyphenol powder in 100 parts of ethanol aqueous solution, and add 0.3 parts of polyacrylate to uniformly disperse to obtain a tea polyphenol mixed solution, and then prepare a dilute p-toluenesulfonic acid solution, using 0.35 parts of p-toluenesulfonic acid and 100 parts of ethanol aqueous solution, add the tea polyphenol mixed solution to the dilute p-toluenesulfonic acid solution, the weight ratio is 1:1, and react for 2 hours to promote the activation of phenolic hydroxyl and hydroxyl groups in tea polyphenols, and obtain a tea polyphenol treated solution; (2) dissolving 9 parts of β-hydroxyethyl acrylate (HEA) in 100 parts of ethanol solution, then adding 0.2 parts of 1-ethyl-(3-dimethylaminopropyl)carbodiimide and 0.15 parts of polyethylene glycol N-hydroxysuccinimide ester, and reacting for 2 hours to obtain an activated crosslinking solution; (3) Mixing the tea polyphenol treatment solution and the activated cross-linking solution in a weight ratio of 1:1, reacting for 4 hours, then adding a sodium hydroxide solution to adjust the pH, wherein the concentration of sodium hydroxide is 1%, so that the pH of the mixed solution is maintained at 6, and then adding an iron-based MOF, wherein the weight ratio of the iron-based MOF to the total mixed solution is 0.5:100, stirring for 2 hours, and purifying to obtain a prepolymer. The purification adopts a conventional membrane filtration method, which is not described in detail here; (4) Add the prepolymer to the viscose spinning solution and control the solid content to 35%. After being fully stirred and mixed, the solution is evenly dispersed, left to stand, degassed, filtered, and then spun according to the conventional wet spinning process. The process is as follows: feeding the spinning solution - spinning the spinneret - coagulation in a coagulation bath - stretching - washing - oiling - drying, characterization - curling - cutting - packaging to obtain the modified fiber. Example 6

[0059] The modified fiber prepared in this embodiment is viscose fiber, wherein the viscose spinning solution (cellulose content 8.9%) used in the embodiment is purchased from Shandong Yinying Chemical Fiber Co., Ltd.; the ethanol solubility in the ethanol aqueous solution mentioned in the embodiment is 60%; the parts in the embodiment are all calculated according to weight parts, solid content = prepolymer weight / spinning solution weight.

[0060] Use the following method: (1) Take tea polyphenol powder with a purity of ≥90w% and a particle size passing through a sieve of 80-100 meshes, dissolve 5 parts of tea polyphenol powder in 100 parts of ethanol aqueous solution, and add 0.3 parts of polyacrylate to uniformly disperse to obtain a tea polyphenol mixed solution, and then prepare a dilute p-toluenesulfonic acid solution, using 0.3 parts of p-toluenesulfonic acid and 100 parts of ethanol aqueous solution, and add the tea polyphenol mixed solution to the dilute p-toluenesulfonic acid solution at a weight ratio of 1:1, and react for 2 hours to promote the activation of phenolic hydroxyl groups and hydroxyl groups in tea polyphenols, thereby obtaining a tea polyphenol treated solution; (2) 8 parts of β-hydroxyethyl acrylate (HEA) were dissolved in 100 parts of ethanol aqueous solution, and then 0.2 parts of 1-ethyl-(3-dimethylaminopropyl) carbodiimide and 0.15 parts of polyethylene glycol N-hydroxysuccinimide ester were added, and the reaction was carried out for 2 hours to obtain an activated cross-linking solution; (3) Mixing the tea polyphenol treatment solution and the activated cross-linking solution in a weight ratio of 1:1, reacting for 2 hours, then adding a sodium hydroxide solution to adjust the pH, wherein the concentration of sodium hydroxide is 1%, so that the pH of the mixed solution is maintained at 6, and then adding an iron-based MOF, wherein the weight ratio of the iron-based MOF to the total mixed solution is 0.5:100, stirring for 2 hours, and purifying to obtain a prepolymer. The purification adopts a conventional membrane filtration method, which is not described in detail here; (4) Add the prepolymer to the viscose spinning solution and control the solid content to 35%. After being fully stirred and mixed, the solution is evenly dispersed, left to stand, degassed, filtered, and then spun according to the conventional wet spinning process. The process is as follows: feeding the spinning solution - spinning the spinneret - coagulation in a coagulation bath - stretching - washing - oiling - drying, characterization - curling - cutting - packaging to obtain the modified fiber.

[0061] Comparative Example 3 The difference between this comparative example and Example 4 is that tea polyphenols is directly added to the viscose spinning solution, and the solid content is controlled to be 35%.

[0062] In the tea polyphenols in Examples 4-6 and Comparative Example 3, catechins account for 70% of the tea polyphenols. Corresponding parameter tests were performed on the fibers obtained in Examples 4-6 and Comparative Example 3, and the specific parameters are shown in Table 2 after taking the average values ​​of multiple tests.

[0063] Table 2

[0064] By comparing Examples 4 to 6 with Comparative Example 3, it can be seen that the fiber prepared by the method of the present invention has a high catechin content, and the fiber has good strength, and especially exhibits good antibacterial and long-lasting antibacterial properties. Example 7

[0065] The modified fiber prepared in this embodiment is acetate fiber; wherein, the acetate spinning solution used in the embodiment is obtained by dissolving diacetate cellulose in N-methylmorpholine-N-oxide, wherein the weight ratio of diacetate cellulose to N-methylmorpholine-N-oxide is 1:4, and the parts in the embodiment are all calculated by weight, and the solid content = prepolymer weight / spinning solution weight.

[0066] Use the following method: (1) Take ginsenoside powder with a purity of ≥90w% and a particle size passing through a sieve of 80-100 meshes, fully dissolve 5 parts of ginsenoside and 8 parts of methacrylic acid-maleic anhydride copolymer in 100 parts of DMAC solvent to obtain a ginsenoside mixed solution, and then prepare a dilute p-toluenesulfonic acid solution by using 0.5 parts of p-toluenesulfonic acid and 100 parts of DMAC solvent at a weight ratio of 1:1, add the ginsenoside mixed solution to the dilute p-toluenesulfonic acid solution, heat to 65°C, react for 2h, and precipitate with a conventional solvent to obtain a prepolymer; (2) The prepolymer and the acetic acid spinning solution are blended to control the solid content to 35%, and iron-based MOF is added at the same time, wherein the iron-based MOF accounts for 0.5% of the total prepolymer and the acetic acid spinning solution, and the iron-based MOF promotes the graft copolymerization between the prepolymer and the hydroxyl or ester group in the acetic acid spinning solution. After being fully stirred and mixed, the mixture is evenly dispersed, allowed to stand, degassed, filtered, and then spun according to a conventional wet spinning process. The process is as follows: spinning solution feeding - spinning head spinning - coagulation bath coagulation molding - stretching - washing - oiling - drying, qualitative - curling - cutting - packaging, and the modified fiber is obtained. Example 8

[0067] The modified fiber prepared in this embodiment is acetate fiber; wherein, the acetate spinning solution used in the embodiment is obtained by dissolving diacetate cellulose in N-methylmorpholine-N-oxide, wherein the weight ratio of diacetate cellulose to N-methylmorpholine-N-oxide is 1:4, and the parts in the embodiment are all calculated by weight, and the solid content = prepolymer weight / spinning solution weight.

[0068] Use the following method: (1) Take ginsenoside powder with a purity of ≥90w% and a particle size passing through a sieve of 80-100 meshes, fully dissolve 4 parts of ginsenoside and 6 parts of methacrylic acid-maleic anhydride copolymer in DMAC solvent to obtain a ginsenoside mixed solution, and then prepare a dilute p-toluenesulfonic acid solution by using 0.4 parts of p-toluenesulfonic acid and 100 parts of DMAC solvent at a weight ratio of 1:1, add the ginsenoside mixed solution to the dilute p-toluenesulfonic acid solution, raise the temperature to 65°C, react for 3 hours, and precipitate the solvent to obtain a prepolymer; (2) The prepolymer and the acetic acid spinning solution are blended to control the solid content to 35%, and iron-based MOF is added at the same time, wherein the iron-based MOF accounts for 0.5% of the total prepolymer and the acetic acid spinning solution, and the iron-based MOF promotes the graft copolymerization between the prepolymer and the hydroxyl or ester group in the acetic acid spinning solution. After being fully stirred and mixed, the mixture is evenly dispersed, allowed to stand, degassed, filtered, and then spun according to a conventional wet spinning process. The process is as follows: spinning solution feeding - spinning head spinning - coagulation bath coagulation molding - stretching - washing - oiling - drying, qualitative - curling - cutting - packaging, and the modified fiber is obtained. Example 9

[0069] The modified fiber prepared in this embodiment is acetate fiber; wherein, the acetate spinning solution used in the embodiment is obtained by dissolving diacetate cellulose in N-methylmorpholine-N-oxide, wherein the weight ratio of diacetate cellulose solution to N-methylmorpholine-N-oxide is 1:4, and the parts in the embodiment are all calculated by weight, and the solid content = prepolymer weight / spinning solution weight.

[0070] Use the following method: (1) Take ginsenoside powder with a purity of ≥90w% and a particle size passing through a sieve of 80-100 meshes, fully dissolve 6 parts of ginsenoside and 10 parts of methacrylic acid-maleic anhydride copolymer in 100 parts of DMAC solvent to obtain a ginsenoside mixed solution, and then prepare a dilute p-toluenesulfonic acid solution by using 0.6 parts of p-toluenesulfonic acid and 100 parts of DMAC solvent at a weight ratio of 1:1, add the ginsenoside mixed solution to the dilute p-toluenesulfonic acid solution, heat to 70°C, react for 2h, and precipitate with a conventional solvent to obtain a prepolymer; (2) The prepolymer and the acetic acid spinning solution are blended to control the solid content to 35%, and iron-based MOF is added at the same time, wherein the iron-based MOF accounts for 0.5% of the total prepolymer and the acetic acid spinning solution, and the iron-based MOF promotes the graft copolymerization between the prepolymer and the hydroxyl or ester group in the acetic acid spinning solution. After being fully stirred and mixed, the mixture is evenly dispersed, allowed to stand, degassed, filtered, and then spun according to a conventional wet spinning process. The process is as follows: spinning solution feeding - spinning head spinning - coagulation bath coagulation molding - stretching - washing - oiling - drying, qualitative - curling - cutting - packaging, and the modified fiber is obtained.

[0071] Comparative Example 4 The difference between this comparative example and Example 7 is that ginsenoside is directly added to the viscose spinning solution, and the solid content is controlled to be 35%.

[0072] In the tea polyphenols of Examples 7-9 and Comparative Example 4, catechins account for 70% of the tea polyphenols. Corresponding parameter tests were performed on the fibers obtained from Examples 7-9 and Comparative Example 4, and the specific parameters after multiple tests and averaging were shown in Table 3.

[0073] Table 3

[0074] By comparing Examples 7 to 9 with Comparative Example 4, it can be seen that the fiber prepared by the method of the present invention has a high content of ginsenosides and good strength, and especially exhibits good antibacterial and long-lasting antibacterial properties.

[0075] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A method for preparing modified fiber by plant extract, characterized in that: The steps include: S1. Obtaining a sugar-free plant extract; wherein the main groups of the plant extract contain one or two of phenolic hydroxyl group and hydroxyl group; S2, pre-treating the plant extract and the copolymer to obtain a prepolymer mixture; the groups of the copolymer can undergo a prepolymerization reaction with the phenolic hydroxyl group and / or hydroxyl group in the plant extract, and can also undergo a chemical reaction with the functional groups in the fiber spinning solution; S3. Wet spinning the prepolymer mixture and the fiber spinning solution to obtain modified fibers.

2. The method according to claim 1, characterized in that The copolymer is one or both of an acrylic ester copolymer and a maleic anhydride grafted polymer.

3. The method according to claim 2, characterized in that The plant extracts are plant leaf bark extracts and rhizome extracts, including one or more of tea extracts, mulberry leaf extracts, bamboo leaf extracts, anthocyanin extracts, paclitaxel extracts, ginseng extracts, ganoderma lucidum extracts, dendrobium extracts, and Panax notoginseng extracts.

4. The method according to claim 3, characterized in that The modified fiber is one of viscose-based fiber, acrylic fiber, acetate fiber, cuprammonium fiber, seaweed fiber and chitin fiber.

5. The method according to claim 4, characterized in that The viscose-based fiber is one or more of viscose, modal, tencel, bamboo fiber and lyocell.

6. The method according to claim 5, characterized in that When the plant extract is tea polyphenols in tea extract, the modified fiber is acrylic fiber, and the specific method is as follows: Step 1: dissolving tea polyphenols in N,N-dimethylacetamide, adding polyvinyl pyrrolidone and MOFs catalyst, stirring and dissolving to obtain a tea polyphenols mixed solution; Step 2: dissolving styrene-maleic anhydride copolymer in N,N-dimethylacetamide, and then adding tea polyphenol mixed solution, stirring to fully mix, heating temperature is 60-80°C, holding time is 3-5h, and purification is performed after the reaction is completed to obtain a prepolymer; Step 3: adding ethylenediamine and potassium persulfate to the polyacrylonitrile spinning solution, the reaction temperature is 60-70° C., the reaction time is 3-5 hours, and a modified spinning solution is obtained; Step 4: Add prepolymer to the modified spinning solution, disperse it evenly, and then perform wet spinning to obtain modified polyacrylonitrile fiber.

7. The method according to claim 5, characterized in that When the plant extract is tea polyphenols and the modified fiber is viscose fiber, the specific method is as follows: Step 1: dissolving tea polyphenol powder in an ethanol aqueous solution, adding polyacrylate, and evenly dispersing to obtain a tea polyphenol mixed solution, and then adding it to a dilute toluenesulfonic acid solution, reacting for 2 to 3 hours, to obtain a tea polyphenol treated solution, wherein the dilute toluenesulfonic acid solution is a mixed solution of p-toluenesulfonic acid and an ethanol aqueous solution; Step 2: dissolving β-hydroxyethyl acrylate in an ethanol aqueous solution, then adding 1-ethyl-(3-dimethylaminopropyl)carbodiimide and polyethylene glycol-based N-hydroxysuccinimide ester in a certain ratio, reacting for 2 to 3 hours to obtain an activated cross-linking solution; Step 3: Mix the tea polyphenol treatment solution and the activated cross-linking solution, react for 2 to 3 hours, then add an alkaline solution to adjust the pH, the pH is controlled between 5 and 7, then add MOFS, stir for 2 to 4 hours, and purify to obtain the prepolymer; Step 4: Add the prepolymer to the viscose spinning solution and obtain the modified fiber by wet spinning.

8. The method according to claim 5, characterized in that When the plant extract is ginsenoside and the modified fiber is cellulose acetate, the specific preparation method is as follows: Step 1: dissolving ginseng soap and methacrylic acid-maleic anhydride in N,N-dimethylacetamide, adding p-toluenesulfonic acid solution, heating to 60-70°C, reacting for 2-3h, and purifying to obtain a prepolymer; Step 2: Add the prepolymer to the acetic acid spinning solution, add MOFS catalyst at the same time, and obtain acetate fiber by wet spinning.

9. A modified fiber, characterized in that: The method is used to prepare the product according to any one of claims 1 to 8.

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