An antibacterial and deodorizing fluff pulp based on plant extracts and its preparation process

Abstract

This invention relates to the field of fluff pulp technology, specifically to an antibacterial and deodorizing fluff pulp based on plant extracts and its preparation process. The pulp comprises activated wood pulp fiber, plant extract antibacterial and deodorizing material, and bamboo extract. The plant extract antibacterial and deodorizing material is composed of a composite coating material formed by cross-linking γ-cyclodextrin and oligochitosan, which coats tea polyphenols, berberine, and artemisia argyi extract. The steps include: S1 preparing the plant extract antibacterial and deodorizing material; S2 activating the wood pulp fiber to obtain activated wood pulp fiber; and S3 mixing the activated wood pulp fiber, the plant extract antibacterial and deodorizing material, and bamboo extract with water, followed by homogenization, shaping, filtration, pressing, and drying to obtain the antibacterial and deodorizing fluff pulp. This invention achieves stable and long-lasting antibacterial and deodorizing functions in fluff pulp by covalently grafting activated wood pulp fiber with the antibacterial material, enhancing the stability of the plant extract through the composite coating material, and regulating the reaction environment and synergistically inhibiting bacteria with bamboo extract.

Description

Technical Field

[0001] This invention relates to the field of fluff pulp technology, specifically to an antibacterial and deodorizing fluff pulp based on plant extracts and its preparation process. Background Technology

[0002] Fluff pulp, a commonly used absorbent material, achieves its antibacterial and deodorizing effects primarily by inhibiting bacterial growth. Bacteria multiplying on fluff pulp decompose waste, producing odorous substances such as ammonia and sulfides. Therefore, by endowing fluff pulp with antibacterial properties, bacterial growth can be effectively prevented, thereby avoiding odor production and achieving deodorization.

[0003] In the prior art, a method for preparing antibacterial fluff pulp has been proposed (CN201410052057.6). This method includes soaking and loosening wood pulp boards, treating them with sodium hydroxide solution to obtain pulp, washing them until neutral, mixing them with a reducing agent solution and a silver nitrate solution, and then reducing silver ions in situ by microwave heating to form nano-silver particles on the surface of cellulose fibers, thereby obtaining nano-silver-loaded wood pulp fibers. These fibers are then paper-formed and dried to obtain antibacterial fluff pulp. In this method, the reducing agent is one or a mixture of glucose, sodium citrate, vitamin C, or ethylene glycol, and the microwave treatment conditions are 360~500 W for 3~10 minutes.

[0004] The aforementioned antibacterial fluff pulp suffers from insufficient antibacterial activity. Specifically, this method relies on single nano-silver as an antibacterial agent, and its antibacterial effect is limited by the uniformity of silver particle dispersion and long-term stability on the fiber surface. The nano-silver does not form a stable chemical bond with the fiber, resulting in poor antibacterial effect of single nano-silver. Summary of the Invention

[0005] To address the technical deficiencies in the background technology, this invention proposes an antibacterial and deodorizing fluff pulp based on plant extracts and its preparation process, which solves the aforementioned technical problems and meets practical needs. The specific technical solution is as follows: An antibacterial and deodorizing fluff pulp based on plant extracts, wherein the antibacterial and deodorizing fluff pulp is a modified fiber material formed by chemically bonding and grafting plant extract antibacterial and deodorizing materials onto activated wood pulp fibers and adsorbing bamboo extract. The activated wood pulp fiber is a wood pulp fiber that has been activated and modified with epichlorohydrin; The plant extract antibacterial and deodorizing material is composed of a composite coating material and plant extracts coated in the composite coating material. The composite coating material is a cross-linked polymer formed by γ-cyclodextrin and oligochitosan through a cross-linking agent. The plant extracts include tea polyphenols, berberine, and artemisia argyi extract.

[0006] As a further technical solution of the present invention, the plant extract antibacterial and deodorizing material is obtained by reacting a composite coating material with a mixed solution of plant extracts. The mixed solution of plant extracts consists of 3-5% plant extracts and 95-97% ethanol-water mixed solvent by mass percentage. In the plant extracts, the weight ratio of tea polyphenols, berberine, and artemisia argyi extract is 3-5:2-4:3-5.

[0007] As a further technical solution of the present invention, the oligomeric chitosan in the composite coating material has a degree of polymerization of 10-20 and a degree of deacylation of 70%-90%.

[0008] A method for preparing antibacterial and deodorizing fluff pulp based on plant extracts includes the following steps: S1. Gamma-cyclodextrin and oligochitosan are dissolved in water, and 50% glutaraldehyde is added to react and prepare a composite coating material. The composite coating material powder is dispersed in water, and a mixed solution of plant essences obtained by dissolving tea polyphenols, berberine and artemisia argyi extract in ethanol-water mixed solvent is added dropwise to carry out the coating reaction. After the reaction is completed, the plant essence antibacterial and deodorizing material is obtained by separation, drying and grinding. S2. After the wood pulp board is water-soluble, broken down by a hydraulic pulper, and subjected to a front-end softening and broom-forming pulping process, wood pulp fiber pulp is obtained. The wood pulp fiber pulp is heated to maintain a temperature of 45-55℃, and epichlorohydrin is added to carry out an activation reaction for 0.5-1h. After the reaction is completed, activated wood pulp fiber is obtained. S3. The pulp formed by mixing activated wood pulp fiber, plant essence antibacterial and deodorizing material, bamboo extract and water in a mass ratio of (80-120): (4-8): (20-40): (530-820) is introduced into the headbox for homogenization. Then it is sprayed out through the spray outlet and forms a wet pulp layer on the forming net. After the wet pulp layer is filtered, formed, pressed and dried at 100℃ for 10 minutes, antibacterial and deodorizing fluff pulp is obtained.

[0009] As a further technical solution of the present invention, in step S1, the coating reaction specifically involves: dispersing the composite coating material powder in water to obtain a 5% composite coating material suspension; slowly adding the plant extract mixed solution dropwise to the composite coating material suspension while stirring, wherein the volume ratio of the plant extract mixed solution to the composite coating material suspension is 1:(3-7); then heating to 60°C and stirring at a constant temperature for 4 hours; subsequently cooling the mixture to room temperature and then refrigerating it in a 4°C refrigerator for 6 hours; then filtering; washing the filter cake with a small amount of cold ethanol; drying the filter cake in a 45°C vacuum drying oven in the dark for 24 hours; and grinding to obtain the plant extract antibacterial and deodorizing material.

[0010] As a further technical solution of the present invention, in step S1, the synthesis of the composite coating material is specifically as follows: γ-cyclodextrin is dissolved in 8 times its mass of water preheated to 55-65℃, oligochitosan is added and stirred until completely dissolved, the pH is adjusted to 4.5-5.5 with dilute hydrochloric acid, 50% glutaraldehyde solution is added dropwise with stirring, the reaction is carried out at a constant temperature of 55-65℃ for 2-4 hours, after cooling, it is refrigerated and allowed to stand, after filtration, the precipitate is washed alternately with low temperature water and anhydrous ethanol, vacuum dried and ground to obtain the composite coating material.

[0011] As a further technical solution of the present invention, in step S1, the weight ratio of γ-cyclodextrin to oligochitosan is 5-10:1, the crosslinking agent used is glutaraldehyde, and the volume mass ratio of glutaraldehyde to the total weight of γ-cyclodextrin and oligochitosan is 0.05-0.15mL:5g.

[0012] As a further technical solution of the present invention, in step S1, the preparation of the plant extract mixed solution is specifically as follows: tea polyphenols, berberine, and artemisia argyi extract are mixed, and an ethanol-water mixed solvent is added, wherein the volume fraction of ethanol in the mixed solvent is 10-20%, and the mixture is stirred in a water bath at 45-55℃ for 20-40 minutes until completely dispersed.

[0013] As a further technical solution of the present invention, in step S2, the mass percentage concentration of wood pulp fiber in the wood pulp fiber pulp is 20-25%, and the mass-volume ratio of wood pulp fiber to epichlorohydrin is 8-10g:1mL.

[0014] The beneficial effects of this invention are as follows: By activating wood pulp fibers with epichlorohydrin, active epoxy groups are introduced onto their surface. Then, a chemical reaction is used to firmly graft plant extract antibacterial and deodorizing materials onto the fiber surface via covalent bonds. The plant extract antibacterial and deodorizing materials are coated with natural ingredients such as tea polyphenols, berberine, and artemisia argyi extract through a complex formed by cross-linking γ-cyclodextrin and oligochitosan, which improves the stability of the active ingredients. In addition, the bamboo extract introduced during the preparation process not only provides a suitable alkaline environment for the bonding reaction, but also, after being adsorbed by the fiber, can produce a synergistic antibacterial effect with the plant extracts, thereby making the antibacterial components stable in combination with the fiber and achieving good and long-lasting antibacterial and deodorizing functions. Detailed Implementation

[0015] The embodiments of the present invention will be described below with reference to relevant examples. The embodiments of the present invention are not limited to those described below, and the present invention relates to necessary knowledge in this technical field. It should be considered as well-known technology in this technical field, and is known and mastered by those skilled in the art. Experimental methods in the following examples that do not specify specific conditions are generally performed under conventional conditions in the art or according to the manufacturer's recommendations. Unless otherwise specified, the raw materials and reagents used are all commercially available from the conventional market. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention are within the scope of protection claimed by the present invention.

[0016] An antibacterial and deodorizing fluff pulp based on plant extracts, wherein the antibacterial and deodorizing fluff pulp is a modified fiber material formed by chemically bonding and grafting plant extract antibacterial and deodorizing materials onto activated wood pulp fibers and adsorbing bamboo extract. The activated wood pulp fiber is a wood pulp fiber that has been activated and modified with epichlorohydrin; The plant extract antibacterial and deodorizing material is composed of a composite coating material and plant extracts coated in the composite coating material. The composite coating material is a cross-linked polymer formed by γ-cyclodextrin and oligochitosan through a cross-linking agent. The plant extracts include tea polyphenols, berberine, and artemisia argyi extract.

[0017] This invention introduces active epoxy groups onto the surface of activated wood pulp fibers after activation with epichlorohydrin. These groups can covalently react with amino groups on the surface of plant extract antibacterial and deodorizing materials to form ring-opening reactions, thus firmly grafting the antibacterial materials onto the surface of the wood pulp fibers. This prevents the antibacterial components from falling off and ensures the longevity of the antibacterial and deodorizing effects.

[0018] The plant-based antibacterial and deodorizing material contains plant extracts, including tea polyphenols, berberine, and artemisia argyi extract, all of which possess natural antibacterial and deodorizing properties. The combination of these three ingredients effectively increases the inhibition of bacterial growth, thereby reducing the substances that produce odors due to the decomposition of feces by bacteria. The plant extracts are encapsulated by a composite coating material formed by cross-linking γ-cyclodextrin and oligochitosan, which effectively improves the stability of active ingredients such as tea polyphenols and prolongs the antibacterial and deodorizing effect.

[0019] In addition, bamboo extract, mainly composed of organic acid salts, is added to the bonding reaction between the plant extract antibacterial and deodorizing materials and the activated wood pulp fibers. This provides a suitable alkaline environment for the bonding reaction between the plant extract antibacterial and deodorizing materials and the activated wood pulp fibers, ensuring the smooth progress of the grafting reaction. At the same time, it has its own antibacterial properties and works synergistically with the plant extracts to further enhance the overall antibacterial effect, ultimately achieving stable and long-lasting antibacterial and deodorizing functions.

[0020] As one of the preferred embodiments of the present invention, the plant extract antibacterial and deodorizing material is obtained by reacting a composite coating material with a mixed solution of plant extracts. The mixed solution of plant extracts consists of 3-5% plant extracts and 95-97% ethanol-water mixed solvent by mass percentage. In the plant extracts, the weight ratio of tea polyphenols, berberine, and artemisia argyi extract is 3-5:2-4:3-5.

[0021] The mixed solution of plant extracts contains 3-5% active ingredients. Using an ethanol-water mixed solvent, tea polyphenols, berberine, and artemisia argyi extract are effectively dissolved. These components are combined in a weight ratio of 3-5:2-4:3-5. Tea polyphenols can disrupt bacterial cell structure, berberine can inhibit bacterial enzyme activity, and artemisia argyi extract has inhibitory effects on various bacteria. The synergistic effect of these three components enhances the broad spectrum and effectiveness of antibacterial activity. The plant extracts are protected by a composite material formed by the cross-linking of γ-cyclodextrin and oligochitosan, thus maintaining stable existence on the wood pulp fiber through chemical bonding. This provides long-term inhibition of bacterial growth and prevents the decomposition of waste by bacteria, thus preventing the production of odorous substances such as ammonia, achieving a long-lasting antibacterial and deodorizing effect.

[0022] As one of the preferred embodiments of the present invention, the oligomeric chitosan in the composite coating material has a degree of polymerization of 10-20 and a degree of deacylation of 70%-90%.

[0023] Oligo-chitosan possesses excellent water solubility, enabling it to mix thoroughly and uniformly with γ-cyclodextrin in an aqueous phase and undergo a glutaraldehyde cross-linking reaction, thereby forming a structurally uniform composite coating material. Compared to high-molecular-weight chitosan, the composite material obtained after cross-linking oligo-chitosan with γ-cyclodextrin has a smaller molecular size and finer particles. This allows the dried composite coating material powder to be more easily redispersed in water during subsequent steps of coating plant extracts, forming a stable suspension and ensuring sufficient contact between the powder and the plant extract mixture for effective coating.

[0024] A method for preparing antibacterial and deodorizing fluff pulp based on plant extracts includes the following steps: S1. Gamma-cyclodextrin and oligochitosan are dissolved in water, and 50% glutaraldehyde is added to react and prepare a composite coating material. The composite coating material powder is dispersed in water, and a mixed solution of plant essences obtained by dissolving tea polyphenols, berberine and artemisia argyi extract in ethanol-water mixed solvent is added dropwise to carry out the coating reaction. After the reaction is completed, the plant essence antibacterial and deodorizing material is obtained by separation, drying and grinding. S2. After the wood pulp board is water-soluble, broken down by a hydraulic pulper, and subjected to a front-end softening and broom-forming pulping process, wood pulp fiber pulp is obtained. The wood pulp fiber pulp is heated to maintain a temperature of 45-55℃, and epichlorohydrin is added to carry out an activation reaction for 0.5-1h. After the reaction is completed, activated wood pulp fiber is obtained. S3. The pulp formed by mixing activated wood pulp fiber, plant essence antibacterial and deodorizing material, bamboo extract and water in a mass ratio of (80-120): (4-8): (20-40): (530-820) is introduced into the headbox for homogenization. Then it is sprayed out through the spray outlet and forms a wet pulp layer on the forming net. After the wet pulp layer is filtered, formed, pressed and dried at 100℃ for 10 minutes, antibacterial and deodorizing fluff pulp is obtained.

[0025] In the method for preparing antibacterial and deodorizing fluff pulp of the present invention, step S1 prepares a plant extract antibacterial and deodorizing material. By controlling the synthesis conditions of the composite coating material, γ-cyclodextrin and oligochitosan are fully cross-linked, and then reacted with a mixed solution of plant extracts to achieve effective coating of tea polyphenols, berberine, and Artemisia argyi extract. Step S2 activates the wood pulp fiber by introducing active epoxy groups on the fiber surface through the activation reaction of epichlorohydrin under alkaline conditions, providing reaction sites for the bonding reaction with the plant extract antibacterial and deodorizing material. Step S3 involves mixing activated wood pulp, plant extract antibacterial and deodorizing materials, and bamboo extract in a specific ratio. Bamboo extract provides a suitable alkaline environment, which promotes the ring-opening reaction between the epoxy groups on the surface of the activated fiber and the amino groups on the surface of the antibacterial material, thereby achieving covalent grafting.

[0026] In step S3, the solution of bamboo extract is weakly alkaline, and bamboo extract itself also has a good antibacterial effect. After mixing activated wood pulp fiber, plant essence antibacterial and deodorizing material, bamboo extract, and water in a certain mass ratio, the pH of the reaction system can be naturally adjusted to 8.5-9.5, which is just suitable for the ring-opening bonding reaction between the epoxy groups on the surface of activated wood pulp fiber and the amino groups on the surface of plant essence antibacterial and deodorizing material. No additional alkaline reagent is needed. By homogenizing in the headbox, the activated fiber, antibacterial material, and bamboo extract are evenly dispersed and reacted in the system. Then, the mixture is sprayed out through the spray outlet and forms a wet pulp layer on the forming screen. After the wet pulp layer is filtered, formed, pressed, and dried at 100°C for 10 minutes, antibacterial and deodorizing fluff pulp is obtained.

[0027] It should be noted that in step S3, the preparation method of bamboo extract is as follows: 100 parts of bamboo vinegar stock solution are mixed evenly with 5-10 parts of calcium carbonate, then the pH value is adjusted to 5-6 with sodium hydroxide solution, the supernatant is filtered, 5-10 parts of activated carbon are added, the mixture is stirred for 5-10 minutes, filtered, and bamboo extract with a solid content of 20-35% is obtained. Through the coordinated steps S1-S3, the antibacterial material is firmly bonded to the wood pulp fiber, and the bamboo extract is fully adsorbed onto the fiber, working synergistically with the plant extracts to exert an antibacterial effect. This coordinated process effectively preserves the activity of each antibacterial component, prevents its detachment, and ultimately achieves a stable and long-lasting antibacterial and deodorizing effect.

[0028] As one of the preferred embodiments of the present invention, in step S1, the coating reaction specifically involves: dispersing the composite coating material powder in water to obtain a 5% composite coating material suspension; slowly adding a mixed solution of plant extracts to the composite coating material suspension while stirring, wherein the volume ratio of the mixed solution of plant extracts to the suspension of composite coating materials is 1:(3-7); then heating to 60°C and stirring at a constant temperature for 4 hours; subsequently cooling the mixture to room temperature and then refrigerating it in a 4°C refrigerator for 6 hours; then filtering; washing the filter cake with a small amount of cold ethanol; drying the filter cake in a vacuum drying oven at 45°C in the dark for 24 hours; and grinding to obtain a plant extract antibacterial and deodorizing material.

[0029] In step S1, the composite coating material is prepared into a 5% suspension. Then, the mixed solution of plant extracts is slowly added dropwise to the suspension of the composite coating material. The temperature is then raised to 60°C and stirred at a constant temperature for 4 hours, which helps the plant extract components to diffuse more effectively and enter the cavity of γ-cyclodextrin to form a stable inclusion complex. After the reaction is completed, the system is cooled to room temperature and then refrigerated at 4°C, which allows the structure of the coated complex to stabilize and form, and also allows it to precipitate better. After filtration, a small amount of unencapsulated plant extracts are washed away with cold ethanol. Then, the mixture is dried at low temperature in the dark and ground, and passed through a 200-mesh sieve to obtain the plant extract antibacterial and deodorizing material.

[0030] As one of the preferred embodiments of the present invention, in step S1, the synthesis of the composite coating material is specifically as follows: γ-cyclodextrin is dissolved in 8 times its mass of water preheated to 55-65℃, oligochitosan is added and stirred until completely dissolved, the pH is adjusted to 4.5-5.5 with dilute hydrochloric acid, 50% glutaraldehyde solution is added dropwise with stirring, the reaction is carried out at a constant temperature of 55-65℃ for 2-4 hours, after cooling, it is refrigerated and allowed to stand, after filtration, the precipitate is washed alternately with low temperature water and anhydrous ethanol, vacuum dried and ground to obtain the composite coating material.

[0031] Further, in step S1, the weight ratio of γ-cyclodextrin to oligochitosan is 5-10:1, the crosslinking agent used is glutaraldehyde, and the volume mass ratio of glutaraldehyde to the total weight of γ-cyclodextrin and oligochitosan is 0.05-0.15mL:5g.

[0032] Gamma-cyclodextrin and oligochitosan were dissolved in water preheated to 55-65℃. The pH of the system was adjusted to a weakly acidic environment of 4.5-5.5 with dilute hydrochloric acid. A specific amount of glutaraldehyde solution was slowly added dropwise under stirring, and the reaction was carried out at a constant temperature of 55-65℃ for 2-4 hours. Glutaraldehyde can form a cross-linking structure between some hydroxyl groups of γ-cyclodextrin and some amino groups of oligochitosan, ensuring sufficient but not excessive cross-linking and avoiding the material becoming too dense, which would affect the subsequent adsorption and encapsulation ability of plant extracts. After the reaction, the mixture was cooled, refrigerated, and filtered. Finally, unreacted monomers and byproducts were removed by alternating washing with low-temperature water and ethanol. The mixture was then vacuum dried and ground, and passed through a 200-mesh sieve to obtain a powdered composite coating material.

[0033] As one of the preferred embodiments of the present invention, in step S1, the preparation of the plant extract mixed solution is specifically as follows: tea polyphenols, berberine, and artemisia argyi extract are mixed, and an ethanol-water mixed solvent is added, wherein the volume fraction of ethanol in the mixed solvent is 10-20%, and the mixture is stirred in a water bath at 45-55°C for 20-40 minutes until completely dispersed.

[0034] Choosing a mixed solvent with an ethanol volume fraction of 10-20% can simultaneously improve the solubility of the three plant extracts. By stirring in a water bath at 45-55℃ for 20-40 minutes, it can effectively dissolve the lipid-soluble components in the more hydrophobic Artemisia argyi extract while ensuring that the more water-soluble components such as berberine do not precipitate out, thus achieving the common dissolution of all components.

[0035] As one of the preferred embodiments of the present invention, in step S2, the mass percentage concentration of wood pulp fiber in the wood pulp fiber pulp is 20-25%, and the mass-volume ratio of wood pulp fiber to epichlorohydrin is 8-10g:1mL.

[0036] In step S2, the wood pulp board is subjected to water solubilization, hydraulic pulping, and front-end softening and broom-forming pulping processes to obtain wood pulp fiber pulp. The wood pulp fiber pulp is heated to 45-55℃, and epichlorohydrin is added for activation reaction. The reaction time is 0.5-1h, introducing epoxy groups on the surface of the wood pulp fiber. After the reaction is completed, it needs to be washed to neutral and dried at low temperature to remove residual reagents, thereby obtaining activated wood pulp fiber.

[0037] The present invention will be further described below through examples and comparative examples. Example 1 S1. Dissolve γ-cyclodextrin and oligochitosan (degree of polymerization 10-20, degree of deacylation 70%-90%) in 8 times their weight of water preheated to 55-65℃ at a weight ratio of 5:1. Adjust the pH to 5 with dilute hydrochloric acid. Add 50% glutaraldehyde solution dropwise while stirring. The volume-to-mass ratio of glutaraldehyde to γ-cyclodextrin and oligochitosan is 0.1mL:5g. React at 60℃ for 3 hours. After cooling, refrigerate and let stand. Filter and wash the precipitate alternately with low-temperature water and anhydrous ethanol. Vacuum dry and grind to obtain the composite coating material. Disperse the composite coating material powder in water to obtain a 5% composite coating material suspension. Prepare a mixed solution of plant extracts: Mix tea polyphenols, berberine, and artemisia argyi extract in a weight ratio of 4:3:4, and add 10% ethanol. A 20% ethanol-water mixed solvent and a plant extract mixed solution, by mass percentage, consist of 4% plant extracts and 96% ethanol-water mixed solvent. The mixture is stirred in a 50°C water bath for 30 minutes until completely dispersed. While stirring, the plant extract mixed solution is slowly added dropwise to the suspension of the composite coating material at a volume ratio of 1:5. The temperature is then raised to 60°C and the mixture is stirred and coated at a constant temperature for 4 hours. The mixture is then cooled to room temperature and refrigerated at 4°C for 6 hours. After filtration, the filter cake is washed with a small amount of cold ethanol and dried in a 45°C vacuum drying oven in the dark for 24 hours. The mixture is then ground to obtain the plant extract antibacterial and deodorizing material.

[0038] S2. After the wood pulp board is water-soluble, broken down by a hydraulic pulper, and subjected to a front-end softening and broom-forming pulping process, a wood pulp fiber pulp with a concentration of 22.5% is obtained. The wood pulp fiber pulp is heated to maintain a temperature of 45-55℃, and epichlorohydrin is added at a weight-volume ratio of 9g:1mL to wood pulp fiber for activation reaction. The reaction time is 0.75h. After the reaction is completed, the pulp is washed and dried to obtain activated wood pulp fiber. S3. The pulp formed by mixing activated wood pulp fiber, plant extract antibacterial and deodorizing material, bamboo extract and water in a mass ratio of 100:6:30:675 is introduced into the headbox for homogenization. Then it is sprayed out through the spray outlet and forms a wet pulp layer on the forming screen. After the wet pulp layer is filtered, formed, pressed and dried at 100°C for 10 minutes, antibacterial and deodorizing fluff pulp is obtained.

[0039] Example 2 The difference between Example 2 and Example 1 is as follows: In S1, the mixed solution of plant extracts is composed of 3% plant extracts and 97% ethanol-water mixed solvent by mass percentage, and the weight ratio of tea polyphenols, berberine, and artemisia argyi extract is 3:2:3; in S3, the activated wood pulp fiber, plant extract antibacterial and deodorizing material, bamboo extract, and water are in a mass ratio of 120:4:30:820, and the remaining steps and parameters are completely consistent with those of Example 1.

[0040] Example 3 The difference between Example 3 and Example 1 is as follows: In S1, the mixed solution of plant extracts is composed of 5% plant extracts and 95% ethanol-water mixed solvent by mass percentage, and the weight ratio of tea polyphenols, berberine, and artemisia argyi extract is 5:4:5; in S3, the mass ratio of activated wood pulp fiber, plant extract antibacterial and deodorizing material, and bamboo extract is 80:8:40:530, and the remaining steps and parameters are completely consistent with those of Example 1.

[0041] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that in step S1, when synthesizing the composite coating material, γ-cyclodextrin was replaced with β-cyclodextrin in equimolar amounts; the remaining steps and parameters were completely consistent with those of Example 1.

[0042] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that in step S1, oligochitosan is replaced with ordinary chitosan (degree of polymerization 25-50); the remaining steps and parameters are completely consistent with Example 1.

[0043] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that in step S1, the oligochitosan was replaced with chitosan oligosaccharide (degree of polymerization 5-10); the remaining steps and parameters are completely consistent with Example 1.

[0044] Comparative Example 4 The difference between Comparative Example 4 and Example 1 is that in step S1, when preparing the mixed solution of plant extracts, the tea polyphenol component is missing, and only berberine and artemisia argyi extract are retained, and the weight ratio of berberine to artemisia argyi extract is 3:4; the remaining steps and parameters are completely consistent with Example 1.

[0045] Comparative Example 5 The difference between Comparative Example 5 and Example 1 is that in step S1, when preparing the mixed solution of plant extracts, the berberine component is missing, and only tea polyphenols and artemisia argyi extract are retained, and the weight ratio of tea polyphenols to artemisia argyi extract is 4:4; the remaining steps and parameters are completely consistent with Example 1.

[0046] Comparative Example 6 The difference between Comparative Example 6 and Example 1 is that in step S1, when preparing the mixed solution of plant extracts, the Artemisia argyi extract component is missing, and only tea polyphenols and berberine are retained, and the weight ratio of tea polyphenols to berberine is 4:3; the remaining steps and parameters are completely consistent with Example 1.

[0047] Comparative Example 7 The difference between Comparative Example 7 and Example 1 is that in step S3, bamboo extract is not added, but an appropriate amount of NaOH solution is added to adjust the pH of the reaction system to 8.5-9.5, and the mass ratio of activated wood pulp fiber to plant essence antibacterial and deodorizing material remains unchanged at 100:6; the remaining steps and parameters are completely consistent with Example 1.

[0048] Comparative Example 8 The difference between Comparative Example 8 and Example 1 is that the wood pulp fiber activation treatment in step S2 is omitted, and the raw wood pulp fiber that has not been treated with epichlorohydrin is used directly for the S3 reaction. The amount of bamboo extract and plant essence antibacterial and deodorizing materials added is the same as in Example 1. The remaining steps and parameters are completely consistent with those in Example 1.

[0049] The antibacterial and deodorizing fluff pulps prepared in Examples 1-3 and Comparative Examples 1-8 were evaluated for their antibacterial properties according to GB / T 20944.3-2008. The results are shown in the table below:

[0050] By comparing the performance data of each embodiment with the comparative example, it can be seen that all three embodiments of the present invention exhibit good antibacterial properties, proving that by activating wood pulp fibers with epichlorohydrin and then bonding them with composite materials coated with plant extracts and bamboo extract, a fluff pulp with stable antibacterial function can be prepared, and the performance increases with the increase of plant extract content. Example 3 shows the best effect, which indicates that within the range of the formulation, the effective loading of active substances is a direct way to improve performance.

[0051] Comparative Example 1 shows that replacing γ-cyclodextrin with β-cyclodextrin leads to a decrease in performance. This is mainly because the two have different spatial structures, which affects their coating and protection effects on plant extracts, especially Artemisia argyi extract with larger molecular size. Comparative Examples 2 and 3 show that the degree of polymerization of oligochitosan needs to be strictly controlled. Excessive or insufficient polymerization will affect the formation of a uniform and stable coating material and the effective bonding with activated fibers, thereby weakening the antibacterial durability.

[0052] Comparative Examples 4 to 6 demonstrate that tea polyphenols, berberine, and artemisia argyi extract are complementary in their antibacterial effects. The absence of any one of them leads to a narrowing of the antibacterial spectrum or a weakening of its intensity; only through synergy can the best broad-spectrum effect be achieved. Comparative Example 7 proves that bamboo extract not only provides the alkaline environment required for the reaction but also contributes to antibacterial activity itself. The significant decline in performance in Comparative Example 8 directly confirms that without the chemical bonds formed by epichlorohydrin activation, the antibacterial components adsorbed solely by physical adsorption are easily detached, failing to achieve the long-lasting antibacterial effect required by the product.

[0053] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An antibacterial and deodorizing fluff pulp based on plant extracts, characterized in that, The antibacterial and deodorizing fluff pulp is a modified fiber material formed by chemically bonding activated wood pulp fibers with plant extract antibacterial and deodorizing materials and adsorbing bamboo extract. The activated wood pulp fiber is a wood pulp fiber that has been activated and modified with epichlorohydrin; The plant extract antibacterial and deodorizing material is composed of a composite coating material and plant extracts coated in the composite coating material. The composite coating material is a cross-linked polymer formed by γ-cyclodextrin and oligochitosan through a cross-linking agent. The plant extracts include tea polyphenols, berberine, and artemisia argyi extract.

2. The antibacterial and deodorizing fluff pulp based on plant extracts according to claim 1, characterized in that, The plant extract antibacterial and deodorizing material is obtained by reacting a composite coating material with a mixed solution of plant extracts. The mixed solution of plant extracts consists of 3-5% plant extracts and 95-97% ethanol-water mixed solvent by mass percentage. In the plant extracts, the weight ratio of tea polyphenols, berberine, and artemisia argyi extract is 3-5:2-4:3-5.

3. The antibacterial and deodorizing fluff pulp based on plant extracts according to claim 1, characterized in that, The oligomeric chitosan in the composite coating material has a degree of polymerization of 10-20 and a degree of deacylation of 70%-90%.

4. The method for preparing antibacterial and deodorizing fluff pulp based on plant extracts according to any one of claims 1 to 3, characterized in that, Includes the following steps: S1. Gamma-cyclodextrin and oligochitosan are dissolved in water, and 50% glutaraldehyde is added to react and prepare a composite coating material. The composite coating material powder is dispersed in water, and a mixed solution of plant essences obtained by dissolving tea polyphenols, berberine and artemisia argyi extract in ethanol-water mixed solvent is added dropwise to carry out the coating reaction. After the reaction is completed, the plant essence antibacterial and deodorizing material is obtained by separation, drying and grinding. S2. The wood pulp board is subjected to water-soluble pulping, hydraulic pulping, and front-end softening and pulping processes to obtain wood pulp fiber pulp. The wood pulp fiber pulp is heated to maintain a temperature of 45-55℃, and epichlorohydrin is added to carry out an activation reaction for 0.5-1h. After the reaction is completed, activated wood pulp fiber is obtained. S3. The pulp formed by mixing activated wood pulp fiber, plant essence antibacterial and deodorizing material, bamboo extract and water in a mass ratio of (80-120): (4-8): (20-40): (530-820) is introduced into the headbox for homogenization. Then it is sprayed out through the spray outlet and forms a wet pulp layer on the forming net. After the wet pulp layer is filtered, formed, pressed and dried at 100℃ for 10 minutes, antibacterial and deodorizing fluff pulp is obtained.

5. The method for preparing antibacterial and deodorizing fluff pulp based on plant extracts according to claim 4, characterized in that, In step S1, the coating reaction specifically involves: dispersing the composite coating material powder in water to obtain a 5% composite coating material suspension; slowly adding a mixed solution of plant extracts to the composite coating material suspension while stirring, wherein the volume ratio of the mixed solution of plant extracts to the suspension of composite coating materials is 1:(3-7); then heating to 60°C and stirring at a constant temperature for 4 hours; subsequently cooling the mixture to room temperature and then refrigerating it in a 4°C refrigerator for 6 hours; then filtering; washing the filter cake with a small amount of cold ethanol; drying the filter cake in a vacuum drying oven at 45°C in the dark for 24 hours; and grinding to obtain the plant extract antibacterial and deodorizing material.

6. The method for preparing antibacterial and deodorizing fluff pulp based on plant extracts according to claim 4, characterized in that, In step S1, the synthesis of the composite coating material is specifically as follows: γ-cyclodextrin is dissolved in 8 times its mass of water preheated to 55-65℃, oligochitosan is added and stirred until completely dissolved, the pH is adjusted to 4.5-5.5 with dilute hydrochloric acid, 50% glutaraldehyde solution is added dropwise with stirring, the reaction is carried out at a constant temperature of 55-65℃ for 2-4 hours, after cooling, it is refrigerated and allowed to stand, after filtration, the precipitate is washed alternately with low temperature water and anhydrous ethanol, vacuum dried and ground to obtain the composite coating material.

7. The method for preparing antibacterial and deodorizing fluff pulp based on plant extracts according to claim 6, characterized in that, In step S1, the weight ratio of γ-cyclodextrin to oligochitosan is 5-10:1, the crosslinking agent used is glutaraldehyde, and the volume mass ratio of glutaraldehyde to the total weight of γ-cyclodextrin and oligochitosan is 0.05-0.15mL:5g.

8. The method for preparing antibacterial and deodorizing fluff pulp based on plant extracts according to claim 4, characterized in that, In step S1, the preparation of the plant extract mixed solution is specifically as follows: tea polyphenols, berberine, and artemisia argyi extract are mixed, and an ethanol-water mixed solvent is added. The volume fraction of ethanol in the mixed solvent is 10-20%, and the mixture is stirred in a water bath at 45-55℃ for 20-40 minutes until it is completely dispersed.

9. The method for preparing antibacterial and deodorizing fluff pulp based on plant extracts according to claim 4, characterized in that, In step S2, the mass percentage concentration of wood pulp fiber in the wood pulp fiber pulp is 20-25%, and the mass-volume ratio of wood pulp fiber to epichlorohydrin is 8-10g:1mL.

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