Preparation method of functional viscose fiber based on enzyme catalysis covalent grafting

Abstract

The invention relates to the technical field of textile materials and textile engineering, and discloses a preparation method of functional viscose fibers based on enzyme catalysis covalent grafting. The preparation method comprises the following steps: firstly, loading a tea polyphenol extract on the surface of a fiber by using a weakly acidic oil-in-water spinning oil agent, then applying a laccase treatment solution, and performing stepped low-temperature drying to catalyze an active component phenolic hydroxyl group and a cellulose alcoholic hydroxyl group to form a stable ether bond. According to the method, high retention and lasting fixation of active ingredients are achieved, the obtained fiber has excellent antibacterial and antioxidant performance, and the process is mild, compatible with an existing production line, safe and environmentally friendly.

Description

Technical Field

[0001] This invention relates to the field of textile materials and textile engineering technology, and to a method for preparing functional viscose fibers based on enzyme-catalyzed covalent grafting. Background Technology

[0002] Viscose fiber, as a regenerated cellulose fiber, is widely used in mask base fabrics, disposable hygiene products, and underwear fabrics due to its excellent skin-friendliness and breathability. With the upgrading of demand for functional textiles, grafting natural active ingredients onto the surface of viscose fiber to endow it with antibacterial, antioxidant, and anti-inflammatory functions has become a hot research topic in the industry.

[0003] Existing methods for combining natural plant extracts with viscose fibers mainly involve post-spinning impregnation and spraying. These methods have the following drawbacks: First, the active ingredients are mostly physically adsorbed, resulting in poor water resistance and easy loss. Second, the processing requires additional steps, leading to low production efficiency and high costs. Third, some processes use strong acids, high temperatures, or strong oxidants, which destroy the active ingredients of the plant extracts and significantly reduce their activity.

[0004] Spinning oils are essential auxiliaries in viscose fiber production, primarily functioning to regulate fiber friction properties, eliminate static electricity, and ensure smooth spinning and subsequent processing. Existing viscose spinning oils mostly consist of lubricants, emulsifiers, and antistatic agents, only providing basic processing functions. Directly adding plant extracts to conventional spinning oils easily leads to component aggregation and oxidative deactivation, and they fail to form a stable bond with the fiber, thus failing to meet the practical application requirements of functional fibers.

[0005] Therefore, developing a spinning oil and grafting method that is compatible with viscose fiber spinning process, can stably carry plant extracts, and can graft the active ingredients of plant extracts onto the fiber surface through covalent bonds during the conventional oiling step without damaging the active ingredients throughout the process has become an urgent technical problem to be solved. Summary of the Invention

[0006] The purpose of this invention is to provide a method for preparing functional viscose fibers based on enzyme-catalyzed covalent grafting, in order to solve the existing technical problems of low binding strength between natural active ingredients and viscose fibers, easy inactivation, and poor process adaptability.

[0007] The technical solution of the present invention is as follows:

[0008] A method for preparing functional viscose fibers based on enzyme-catalyzed covalent grafting, characterized by comprising the following steps:

[0009] (1) Apply a functional spinning oil containing tea polyphenol extract to the surface of viscose fiber;

[0010] (2) Apply the enzyme-catalyzed crosslinking treatment solution containing laccase to the fiber surface after step (1);

[0011] (3) The fibers treated in step (2) are dried in the first stage and the second stage in sequence. The first stage is carried out at a temperature of 48-52℃ and a relative humidity of 60-70%, and the second stage is carried out at a temperature of 60-65℃ and a relative humidity of less than 30%, thus obtaining functional viscose fiber.

[0012] Further optimization resulted in the functional viscose fiber having a pH value of 5.0-6.0.

[0013] Further optimization is achieved by comprising the following raw materials in parts by weight: 10-20 parts base oil phase, 25-40 parts emulsifier, 5-10 parts antistatic agent, 3-6 parts tea polyphenol extract, 0.5-1 part active protectant, with the remainder being solvent.

[0014] Further optimization involves selecting the base oil phase from 10... # The white oil and sulfurized castor oil, the emulsifiers are selected from PEG400MO and Tween 80 in a mass ratio of 3-1.5:1, the antistatic agent is selected from potassium salt of fatty alcohol polyoxyethylene ether phosphate, and the active protectant is selected from vitamin E and xanthan gum in a mass ratio of 1:2-3.

[0015] Further optimization is achieved by including the following steps in the preparation method of the functional spinning oil:

[0016] 1) Dissolve the tea polyphenol extract in a solvent and stir in the dark until completely dissolved; add vitamin E and continue stirring for 4-6 minutes to obtain the mother liquor;

[0017] 2) Mix PEG400MO and Tween 80 at 40-45℃ and 550-650r / min for 20min, add the base oil phase, and continue stirring for 27-32min to form a homogeneous oil phase;

[0018] 3) While stirring at 750-850 r / min, slowly drop the above mother liquor into the oil phase. After the drop is complete, add the antistatic agent and xanthan gum, and continue stirring for 30-40 min to form a stable emulsion.

[0019] 4) Add deionized water and stir well. Adjust the pH of the system to 5.0-6.0 with citrate buffer solution. Store in the dark and at room temperature for later use.

[0020] Further optimization is achieved by applying the functional spinning oil agent in step (1) using the impregnation-rolling method, controlling the fiber oil content to be 0.25-0.3%, the impregnation temperature to be 40-50℃, and the impregnation time to be 1-5 min; in step (2), applying the enzyme-catalyzed crosslinking treatment liquid using the spray or low-liquid impregnation method.

[0021] Further optimization involves using the citrate buffer solution as the medium for the enzyme-catalyzed cross-linking treatment solution, and adding laccase at a rate of 1.0-2.0% of the total mass of the fiber surface active ingredients.

[0022] Further optimization was made, with the first stage drying time being 25-30 minutes and the second stage drying time being 10-15 minutes.

[0023] The beneficial effects of this application are:

[0024] 1. By constructing a weakly acidic (pH=5.0-6.0) oil-in-water emulsion system and combining it with an active protectant, a stable environment is provided for light- and heat-sensitive tea polyphenol extracts. This system can effectively inhibit oxidation throughout the entire process of oil preparation, storage and oiling, ensuring that the retention rate of active ingredients in the final fiber is as high as 88% or more, fundamentally overcoming the technical bottleneck of easy degradation and inactivation of natural active ingredients in traditional processing.

[0025] 2. This invention selectively oxidizes the non-core, non-functionally essential phenolic hydroxyl groups, transforming them into more active quinones or free radical intermediates. Combined with laccase-specific catalysis, the phenolic hydroxyl groups of the catechin element molecules of tea polyphenols form stable ether bonds with the alcohol hydroxyl groups of cellulose, achieving covalent fixation. This chemical bonding method firmly anchors the active ingredients to the fiber surface. After vigorous shaking in deionized water for 24 hours, the dissolution rate of the active ingredients is still less than 3%, and the water wash resistance is far superior to that of physical adsorption methods, ensuring the durability and reliability of the fiber's antibacterial and antioxidant functions.

[0026] 3. This invention adopts a two-step method to separate the spinning oil containing active ingredients from the enzyme catalytic liquid, which cleverly solves the contradiction between storage stability and use activity. The entire functionalization process can be seamlessly integrated into the oiling and drying process after conventional spinning of viscose fibers without the need for new large-scale special equipment. This realizes the integration of functionalization processing with the original production process, significantly improves production efficiency, and reduces transformation costs.

[0027] 4. By covalently grafting, the problem of easy loss of active ingredients is solved. The fiber obtains excellent antibacterial, antioxidant and anti-inflammatory properties derived from tea polyphenols, and its function is not affected by washing. At the same time, the whole process adopts bio-enzyme catalysis and gentle step drying, avoiding the use of strong acids, strong oxidants or high-temperature cross-linking agents. The oil component is low in toxicity and biodegradable. The finished fiber has no harmful residues, is safe and environmentally friendly, and fully meets the safety standards of daily chemical products such as mask base cloth and high-end hygiene products.

[0028] In summary, this invention has achieved groundbreaking progress in terms of activity protection, binding strength, process integration, and overall performance, providing a practical and feasible technical solution for developing high-performance, high-value-added functional cellulose fiber products. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention; that is, the described embodiments are merely some embodiments of the invention, and not all embodiments. The components of the embodiments of the invention described and shown herein can generally be arranged and designed in various different configurations.

[0030] Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0031] It should be noted that relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0032] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0033] Example 1

[0034] Functional spinning oils comprise the following raw materials in parts by weight:

[0035] 4.5 parts of tea polyphenol extract

[0036] 0.8 parts of active protective agent

[0037] 15 parts of base oil phase

[0038] 30 parts of emulsion system

[0039] 8 parts of antistatic agent

[0040] The base oil phase is 10 by mass ratio of 1:1. # The emulsion system consisted of white oil and sulfurized castor oil in a 3:1 mass ratio of PEG400MO (polyethylene glycol monooleate) and Tween 80 (0.08% concentration). The antistatic agent was potassium salt of fatty alcohol polyoxyethylene ether phosphate. The activity protectant was vitamin E and xanthan gum in a 1:2 mass ratio. The solvent was a mixture of deionized water and anhydrous ethanol (final ethanol concentration 4%). The pH adjuster was a 10% dilute citric acid solution. The amount of white rot fungus laccase added to the enzyme-catalyzed cross-linking treatment solution was 1.5% of the total mass of active ingredients on the fiber. 0.05M citrate buffer (pH=5.0) was also used.

[0041] A method for preparing functional viscose fibers based on enzyme-catalyzed covalent grafting includes the following steps:

[0042] 1. Preparation of functional spinning oils

[0043] 1.1 Dissolve the tea polyphenol extract in deionized water containing 4% anhydrous ethanol, stir in the dark until completely dissolved, add vitamin E, and continue stirring in the dark for 5 minutes to obtain a homogeneous mother liquor for later use.

[0044] 1.2 Place PEG400MO and Tween 80 in a 42℃ constant temperature water bath and mechanically stir at 600r / min for 20min. Add the base oil phase and continue stirring at the same speed for 30min to form a homogeneous emulsified oil phase.

[0045] 1.3 Place the emulsified oil phase under continuous stirring at 800 r / min, slowly add the mother liquor dropwise, and after the dropwise addition is complete, add the potassium salt of fatty alcohol polyoxyethylene ether phosphate and xanthan gum, and stir continuously for 40 min in the dark to form a stable oil-in-water emulsion.

[0046] 1.4 Add deionized water containing 4% ethanol to a total of 100 parts, stir and mix well, then adjust the pH of the system to 5.0 with 10% dilute citric acid solution, and store in a sealed container at room temperature away from light for later use.

[0047] 2. Preparation of enzyme-catalyzed cross-linking treatment solution

[0048] Take 1.5% of the total mass of active tea polyphenols from the white rot fungus laccase and disperse it in 0.05M citrate buffer containing 0.08% Tween 80. Gently shake to mix, and strictly prohibit vigorous stirring to prepare the catalytic solution for later use.

[0049] 3. Oiling and loading of active ingredients on viscose fibers

[0050] 3.1 After spinning and stretching, the viscose fiber is naturally cooled to 45°C to remove surface dust;

[0051] 3.2. Using an impregnation-pinching process, the cooled fibers are immersed in a functional spinning oil agent and impregnated for 3 minutes in the dark at a liquor ratio of 1:25 and a temperature of 45°C.

[0052] 3.3. The fibers are removed and uniformly rolled by rollers to precisely control the oil content of the fibers to 0.28%;

[0053] 3.4 Apply the catalytic liquid evenly to the fiber surface by spraying, and control the liquid carry-over rate to make the fiber wet without obvious dripping;

[0054] 4. Stepped low-temperature baking and covalent bond curing

[0055] 4.1 Place the fiber in a humid and hot environment of 50℃ and 65% relative humidity for 28 minutes to achieve the initial formation of ether bonds;

[0056] 4.2 Quickly transfer the fiber to a dry heat environment of 62℃ and 25% relative humidity, and keep it warm and dry for 12 minutes to promote the stabilization of covalent bonds and evaporate excess moisture;

[0057] 4.3. Place the fiber in a 45℃ warm air dryer until the fiber reaches the standard moisture content.

[0058] 5. Finished product collection

[0059] The dried fibers were naturally cooled to room temperature, then sorted and wound up to obtain functional viscose fibers covalently grafted with tea polyphenols.

[0060] Example 2

[0061] Functional spinning oils comprise the following raw materials in parts by weight:

[0062] 3.0 parts of tea polyphenol extract

[0063] 0.5 parts of active protective agent

[0064] 10 parts of base oil phase

[0065] 25 parts of emulsion system

[0066] 5 parts of antistatic agent

[0067] The base oil phase is 10 by mass ratio of 1:1. # The emulsion system consisted of white oil and sulfurized castor oil in a 3:1 mass ratio of PEG400MO (polyethylene glycol monooleate) and Tween 80 (0.05% concentration). The antistatic agent was potassium salt of fatty alcohol polyoxyethylene ether phosphate. The activity protectant was vitamin E and xanthan gum in a 1:2 mass ratio. The solvent was a mixture of deionized water and anhydrous ethanol (final ethanol concentration 3%). The pH adjuster was a 10% dilute citric acid solution. The amount of white rot fungus laccase added to the enzyme-catalyzed cross-linking treatment solution was 1.0% of the total mass of active ingredients on the fiber. 0.05M citrate buffer (pH=6.0) was also used.

[0068] A method for preparing functional viscose fibers based on enzyme-catalyzed covalent grafting includes the following steps:

[0069] 1. Preparation of functional spinning oils

[0070] 1.1 Dissolve the tea polyphenol extract in a solvent, stir in the dark until completely dissolved, add vitamin E, stir in the dark for 5 minutes to obtain a homogeneous mother liquor for later use.

[0071] 1.2 Place PEG400MO and Tween 80 in a 40℃ constant temperature water bath and mechanically stir at 600r / min for 20min. Add the base oil phase and continue stirring at the same speed for 30min to form a homogeneous emulsified oil phase.

[0072] 1.3 Place the emulsified oil phase under continuous stirring at 800 r / min, slowly add the mother liquor dropwise, and after the dropwise addition is complete, add the potassium salt of fatty alcohol polyoxyethylene ether phosphate and xanthan gum, and stir continuously for 40 min in the dark to form a stable oil-in-water emulsion.

[0073] 1.4 Add deionized water containing 3% ethanol to a total of 100 parts, stir and mix well, then adjust the pH of the system to 6.0 with 10% dilute citric acid solution, and store in a sealed container at room temperature away from light for later use.

[0074] 2. Preparation of enzyme-catalyzed cross-linking treatment solution

[0075] Take 1.0% of the total mass of active tea polyphenols from the white rot fungus laccase and disperse it in 0.05M citrate buffer containing 0.05% Tween 80. Gently shake to mix, and strictly prohibit vigorous stirring to prepare the catalytic solution for later use.

[0076] 3. Oiling and loading of active ingredients on viscose fibers

[0077] 3.1 After spinning and stretching, the viscose fibers are naturally cooled to 40°C to remove surface dust;

[0078] 3.2. Using an impregnation-spinning process, the cooled fibers are immersed in a functional spinning oil agent and impregnated for 1 minute in the dark at a liquor ratio of 1:25 and a temperature of 40°C.

[0079] 3.3. Remove the fibers and roll them evenly with rollers to precisely control the oil content to 0.25%;

[0080] 3.4. Apply the catalytic liquid evenly to the fiber surface by low-liquid impregnation method, and control the liquid carry-over rate to make the fiber wet without obvious dripping;

[0081] 4. Stepped low-temperature baking and covalent bond curing

[0082] 4.1 Place the fiber in a humid and hot environment of 48℃ and 60% relative humidity for 25 minutes to achieve the initial formation of ether bonds;

[0083] 4.2 Quickly transfer the fiber to a dry heat environment of 60℃ and 20% relative humidity, keep it warm and dry for 10 minutes to promote the stabilization of covalent bonds and evaporate excess moisture;

[0084] 4.3. Place the fiber in a 40℃ warm air dryer until the fiber reaches the standard moisture content.

[0085] 5. Finished product collection

[0086] The dried fibers were naturally cooled to room temperature, then sorted and wound up to obtain functional viscose fibers covalently grafted with tea polyphenols.

[0087] Example 3

[0088] Functional spinning oils comprise the following raw materials in parts by weight:

[0089] 4.5 parts of tea polyphenol extract

[0090] 0.8 parts of active protective agent

[0091] 15 parts of base oil phase

[0092] 30 parts of emulsion system

[0093] 8 parts of antistatic agent

[0094] The base oil phase is 10 by mass ratio of 1:1. #The emulsion system consisted of white oil and sulfurized castor oil in a 3:1 mass ratio of PEG400MO (polyethylene glycol monooleate) and Tween 80 (0.1% concentration). The antistatic agent was potassium salt of fatty alcohol polyoxyethylene ether phosphate. The activity protectant was vitamin E and xanthan gum in a 1:2 mass ratio. The solvent was a mixture of deionized water and anhydrous ethanol (final ethanol concentration 3%). The pH adjuster was a 10% dilute citric acid solution. The amount of white rot fungus laccase added to the enzyme-catalyzed cross-linking treatment solution was 2.0% of the total mass of active ingredients on the fiber. 0.05M citrate buffer (pH=5.5) was also used.

[0095] A method for preparing functional viscose fibers based on enzyme-catalyzed covalent grafting includes the following steps:

[0096] 1. Preparation of functional spinning oils

[0097] 1.1 Dissolve the tea polyphenol extract in deionized water containing 3% anhydrous ethanol, stir in the dark until completely dissolved, add vitamin E, and continue stirring in the dark for 5 minutes to obtain a homogeneous mother liquor for later use.

[0098] 1.2 Place PEG400MO and Tween 80 in a 45℃ constant temperature water bath and mechanically stir at 600r / min for 20min. Add the base oil phase and continue stirring at the same speed for 30min to form a homogeneous emulsified oil phase.

[0099] 1.3 Place the emulsified oil phase under continuous stirring at 800 r / min, slowly add the mother liquor dropwise, and after the dropwise addition is complete, add the potassium salt of fatty alcohol polyoxyethylene ether phosphate and xanthan gum, and stir continuously for 40 min in the dark to form a stable oil-in-water emulsion.

[0100] 1.4 Add deionized water containing 3% ethanol to a total of 100 parts, stir and mix well, then adjust the pH of the system to 5.5 with 10% dilute citric acid solution, and store in a sealed container at room temperature away from light for later use.

[0101] 2. Preparation of enzyme-catalyzed cross-linking treatment solution

[0102] Take 2.0% of the total mass of active tea polyphenols from the white rot fungus laccase and disperse it in 0.05M citrate buffer containing 0.1% Tween 80. Gently shake to mix, and strictly prohibit vigorous stirring to prepare the catalytic solution for later use.

[0103] 3. Oiling and loading of active ingredients on viscose fibers

[0104] 3.1 After spinning and stretching, the viscose fiber is naturally cooled to 50°C to remove surface dust;

[0105] 3.2. Using an impregnation-pinching process, the cooled fibers are immersed in a functional spinning oil agent and impregnated for 5 minutes in the dark at a liquor ratio of 1:25 and a temperature of 50°C.

[0106] 3.3. Remove the fibers and roll them evenly with rollers to precisely control the oil content to 0.30%;

[0107] 3.4 Apply the catalytic liquid evenly to the fiber surface by spraying, and control the liquid carry-over rate to make the fiber wet without obvious dripping;

[0108] 4. Stepped low-temperature baking and covalent bond curing

[0109] 4.1 Place the fiber in a humid and hot environment of 52℃ and 70% relative humidity for 30 minutes to achieve the initial formation of ether bonds;

[0110] 4.2 Quickly transfer the fiber to a dry heat environment of 65℃ and 30% relative humidity, keep it warm and dry for 15 minutes to promote the stabilization of covalent bonds and evaporate excess moisture;

[0111] 4.3. Place the fiber in a 50℃ warm air dryer until the fiber reaches the standard moisture content.

[0112] 5. Finished product collection

[0113] The dried fibers were allowed to cool naturally to room temperature, then sorted and rolled up to obtain functional fibers covalently grafted with tea polyphenols.

[0114] Viscose fiber.

[0115] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. The scope of patent protection of the present invention shall be determined by the claims. Similarly, any equivalent structural changes made based on the content of the present invention's specification shall also be included within the scope of protection of the present invention.

Claims

1. A method for preparing functional viscose fibers based on enzyme-catalyzed covalent grafting, characterized in that, Includes the following steps: (1) Apply a functional spinning oil containing tea polyphenol extract to the surface of viscose fiber; (2) Apply the enzyme-catalyzed crosslinking treatment solution containing laccase to the fiber surface after step (1); (3) The fibers treated in step (2) are dried in the first stage and the second stage in sequence. The first stage is carried out at a temperature of 48-52℃ and a relative humidity of 60-70%, and the second stage is carried out at a temperature of 60-65℃ and a relative humidity of less than 30%, thus obtaining functional viscose fiber.

2. The preparation method according to claim 1, characterized in that, The functional viscose fiber has a pH value of 5.0-6.

0.

3. The preparation method according to claim 1, characterized in that, The functional spinning oil comprises the following raw materials in parts by weight: 10-20 parts base oil phase, 25-40 parts emulsifier, 5-10 parts antistatic agent, 3-6 parts tea polyphenol extract, 0.5-1 part active protectant, and the balance being solvent.

4. The preparation method according to claim 1, characterized in that, The base oil phase is selected from 10 by mass ratio of 1-3:

1. # The white oil and sulfurized castor oil, the emulsifiers are selected from PEG400MO and Tween 80 in a mass ratio of 3-1.5:1, the antistatic agent is selected from potassium salt of fatty alcohol polyoxyethylene ether phosphate, and the active protectant is selected from vitamin E and xanthan gum in a mass ratio of 1:2-3.

5. The preparation method according to claim 4, characterized in that, The preparation method of the functional spinning oil agent includes the following steps: 1) Dissolve the tea polyphenol extract in a solvent and stir in the dark until completely dissolved; add vitamin E and continue stirring for 4-6 minutes to obtain the mother liquor; 2) Mix PEG400MO and Tween 80 at 40-45℃ and 550-650r / min for 20min, add the base oil phase, and continue stirring for 27-32min to form a homogeneous oil phase; 3) While stirring at 750-850 r / min, slowly drip the above mother liquor into the oil phase. After the dripping is complete, add the antistatic agent and xanthan gum, and continue stirring for 30-40 min to form a stable emulsion. 4) Add deionized water and stir well. Adjust the pH of the system to 5.0-6.0 with citrate buffer solution. Store in the dark at room temperature for later use.

6. The preparation method according to claim 1, characterized in that, In step (1), the functional spinning oil is applied by impregnation-squeezing method, and the fiber oil content is controlled at 0.25-0.3%, the impregnation temperature is 40-50℃, and the impregnation time is 1-5min; in step (2), the enzyme-catalyzed crosslinking treatment liquid is applied by spraying or low-liquid impregnation method.

7. The preparation method according to claim 1, characterized in that, The citrate buffer solution is the medium for the enzyme-catalyzed cross-linking treatment solution, and the amount of laccase added is 1.0-2.0% of the total mass of the fiber surface active ingredients.

8. The preparation method according to claim 1, characterized in that, The drying time for the first stage is 25-30 minutes, and the drying time for the second stage is 10-15 minutes.