Biodegradable wood pulp hydroentangled nonwoven material and method of making same

Abstract

The application provides a biodegradable wood pulp spunlace nonwoven material, which comprises the following raw materials: 60-70 wt% modified wood pulp fibers and 30-40 wt% lyocell fibers, wherein the modified wood pulp fibers are wood pulp fibers subjected to a beating process, then surface modified by a thiophene chloride derivative, and finally in-situ reaction prepared on the modified wood pulp fibers by using FeCl3 as a catalytic oxidant and a hydroxythiophene derivative as a polymerization monomer. The nonwoven material is composed of modified wood pulp fibers and lyocell fibers, and through beating and grinding of the wood pulp fibers and double treatment of polythiophene grafting, more hydrogen bond combination and complex entanglement are formed between the wood pulp fibers, the wood pulp fibers and the lyocell fibers, so as to overcome the problem of weak cohesion strength caused by the length limitation of the wood pulp fibers. The nonwoven material is soft and does not fall off, and has excellent water absorption and degradability.

Description

Technical Field

[0001] This invention belongs to the field of wood pulp nonwoven materials technology, specifically relating to a biodegradable wood pulp hydroentangled nonwoven material and its preparation method. Background Technology

[0002] As people's living standards improve, the demand for disposable hygiene products is increasing, such as wet wipes, wiping cloths, compressed towels, medical sheets, medical pillowcases, medical tablecloths, surgical gowns, and laboratory work clothes. However, the use of disposable hygiene products brings a series of waste disposal problems, which are constantly increasing the burden on the environment. If disposable hygiene products were biodegradable, the environmental burden would be greatly reduced. Wood pulp fiber is a natural cellulose fiber prepared from wood through rubbing and chemical treatment. It has the characteristics of good water absorption, softness, and biodegradability. Using wood pulp fiber as a raw material to prepare nonwoven fabrics can not only alleviate the energy crisis but also achieve sustainable development.

[0003] In nonwoven fabric consolidation technology, hydroentangling utilizes fine, high-pressure water jets to continuously spray the fiber web on the support curtain, causing the fibers in the web to entangle, bind, and consolidate irregularly. This results in a final product with excellent drape, a soft hand feel, and good hygiene. Therefore, hydroentangling for the preparation of nonwoven fabrics has attracted widespread attention: for example, patent CN101619520B discloses a biodegradable composite hydroentangled nonwoven fabric and its production method, and patent CN112962351B discloses a washable wet wipe, its preparation method, and its application.

[0004] The above technology refers to spunlace fabric prepared mainly from wood pulp fiber, which has the advantages of softness and good water absorption. However, wood pulp fiber is short and it is not easy for the fibers to form effective mechanical entanglement, resulting in easy shedding and low wet strength. Therefore, making wood pulp fiber nonwoven fabric have both good water absorption and abrasion resistance and high wet strength is a technical challenge in preparing nonwoven fabric by spunlace method using wood pulp fiber as raw material. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a biodegradable wood pulp spunlace nonwoven material and its preparation method. The nonwoven material is composed of modified wood pulp fibers and lyocell fibers. The modified wood pulp fibers are prepared by first pulping the wood pulp fibers, then surface-modifying them with a thiophene chloride derivative, and finally reacting them in situ on the modified wood pulp fibers using FeCl3 as a catalyst oxidant and a hydroxythiophene derivative as a polymerizing monomer. Through the dual treatment of pulping and grinding of the wood pulp fibers and polythiophene grafting, more hydrogen bonds and complex entanglements are formed between the wood pulp fibers and the lyocell fibers, thus overcoming the problem of weak cohesion due to the length limitation of wood pulp fibers.

[0006] To achieve the above objectives, the following technical solution is adopted:

[0007] A biodegradable wood pulp spunlace nonwoven material comprises the following raw materials: 60-70 wt% modified wood pulp fiber and 30-40 wt% lyocell fiber. The modified wood pulp fiber is prepared by first treating the wood pulp fiber with a pulping process, then modifying its surface with a thiophene chloride derivative, and finally reacting it in situ on the modified wood pulp fiber with FeCl3 as a catalyst oxidant and a hydroxythiophene derivative as a polymer monomer.

[0008] The amount of the thiophene chloride derivative is 5-7 wt% of the wood pulp fiber, and the amount of the hydroxythiophene derivative is 13.5-15 wt% of the wood pulp fiber.

[0009] The thiophene chloride derivative is selected from one or a combination of two or more of 3-thiophene carboxyl chloride, thiophene-3-yl-acetyl chloride, 2-thiophene carboxyl chloride, and 2-thiophene acetyl chloride.

[0010] The hydroxythiophene derivative is selected from one or a combination of two or more of 3-thiophene methanol, 1-(thiophene-3-yl)ethanol, 2-(3-thiophene)ethanol, and thiophene-3-ol.

[0011] Furthermore, the hydroxythiophene derivative is selected from one or a combination of two of 3-thiophene methanol and 2-(3-thiophene)ethanol.

[0012] The lyocell fiber has a specification of 0.9-3.0D and a length of 5-12mm.

[0013] The wood pulp fiber length is 2-8 mm.

[0014] The wood pulp fiber is selected from one or a combination of two of softwood pulp fiber and hardwood pulp fiber.

[0015] The modified wood pulp fiber is prepared by a method comprising the following steps:

[0016] 1) Add water to the wood pulp fiber for pulping treatment, dry it, and obtain oven-dry wood pulp fiber for later use;

[0017] 2) Disperse the oven-dry wood pulp fiber in an anhydrous organic solvent, sonicate, add thiophene chloride derivative and acid binder, mix evenly, and carry out the reaction under controlled temperature. After the reaction is completed, filter, wash and dry to obtain surface-modified wood pulp fiber.

[0018] 3) Under an inert atmosphere, the surface-modified wood pulp fiber is immersed in an anhydrous organic solvent, sonicated, and hydroxythiophene derivative is added. After mixing evenly, a catalytic oxidant solution is added dropwise, and the reaction is carried out under controlled temperature. After the reaction is completed, the fiber is filtered, washed, and dried to obtain modified wood pulp fiber.

[0019] Step 2) Thiophene acyl chloride derivative reacts with hydroxyl groups on wood pulp fibers to obtain wood pulp fibers with thiophene groups modified on the surface. Step 3) Using the thiophene groups modified on the surface of wood pulp fibers as active sites, under the action of a catalytic oxidant, hydroxythiophene derivative is used as a polymerization monomer to in situ graft polythiophene onto the wood pulp fibers.

[0020] In step 1), the pulping process has a freeness of 40-60°SR, a pulping concentration of 4-5wt%, and a pulping wet weight of 8.5-9.5g.

[0021] Step 2) The organic solvent is selected from one or a combination of two or more of dichloromethane, methyl isobutyl ketone, tetrahydrofuran, ethyl acetate, and chloroform; the ultrasonic power is 500-1500W, and the ultrasonic time is 5-30min; the mass ratio of wood pulp fiber to anhydrous organic solvent is 1:80-100; the amount of thiophene chloride derivative is 5-7wt% of wood pulp fiber; the acid-binding agent is selected from one or a combination of two of triethylamine and pyridine, and the mass of the acid-binding agent is 1.7-2.0 times that of the thiophene chloride derivative; the temperature is controlled at 20-30℃; the reaction time is 3-5h; the washing is done with water until neutral; and the drying temperature is 60-100℃.

[0022] Step 3) The organic solvent is selected from one or a combination of two or more of dichloromethane, methyl isobutyl ketone, tetrahydrofuran, ethyl acetate, and chloroform; the mass ratio of the surface-modified wood pulp fiber to the anhydrous organic solvent is 1:80-100; the ultrasonic power is 500-1500W, and the ultrasonic time is 5-30min; the amount of the hydroxythiophene derivative is 13.5-15wt% of the wood pulp fiber; the catalytic oxidant solution is a mixture of FeCl3 and the organic solvent, the FeCl3 concentration in the catalytic oxidant solution is 2-4mol / L, and the catalytic oxidant solution is added dropwise over 0.5-1h; the molar ratio of the catalytic oxidant to the hydroxythiophene derivative is 4-6:1; the temperature is controlled at 20-30℃, and the reaction time is 10-18h; the washing is performed by alternating washing with ethanol and water 1-3 times; the drying temperature is 60-100℃.

[0023] The present invention also provides a method for preparing the above-mentioned biodegradable wood pulp hydroentangled nonwoven material, comprising the following steps:

[0024] Modified wood pulp fibers and lyocell fibers are opened and mixed to prepare a mixed pulp. The mixed pulp is pumped to an inclined wire forming system to output a wet fiber web. The web is then hydroentangled and reinforced on a flat web, hydroentangled and reinforced on a rotary drum, dehydrated, dried, and wound.

[0025] The concentration of the mixed slurry is 0.4-1 g / L.

[0026] The flat web hydroentanglement reinforcement process is as follows: the hydroentanglement needles are perpendicular to the fiber web, the hydroentanglement pressure is 30-80 bar, the diameter of the hydroentanglement needle holes is 0.1-0.15 mm, the number of hydroentanglement channels is 1-3, the speed of the conveying curtain is 5-20 m / min, and the hydroentanglement distance is 30-40 mm.

[0027] The rotary drum hydroentangling reinforcement process has the following parameters: hydroentangling pressure 30-80 bar, water needle diameter 0.1-0.15 mm, and 1-3 hydroentangling passes.

[0028] The dehydration process involves removing excess water using a suction device.

[0029] The drying temperature is 70-130℃, and the drying time is 5-15s.

[0030] Compared with the prior art, the beneficial effects of the present invention are:

[0031] The nonwoven material of this invention is composed of modified wood pulp fiber and lyocell fiber. The modified wood pulp fiber is prepared by first pulping the wood pulp fiber, then modifying its surface with a thiophene chloride derivative, and finally reacting it in situ on the modified wood pulp fiber with FeCl3 as a catalyst oxidant and hydroxythiophene derivative as a polymer monomer. Through the dual treatment of pulping and grinding of wood pulp fiber and polythiophene grafting, more hydrogen bonds and complex entanglements are formed between wood pulp fibers and lyocell fibers, thereby overcoming the problem of weak cohesion due to the length limitation of wood pulp fiber.

[0032] The nonwoven material of this invention is soft, lint-free, and has excellent water absorption and biodegradability. Detailed Implementation

[0033] The present invention will be further described below with reference to specific embodiments, but is not limited to the contents of the specification. Unless otherwise specified, all "parts" mentioned in the embodiments of the present invention are parts by weight. All reagents used are commercially available in the art.

[0034] The wood pulp fiber is hardwood pulp fiber, purchased from Hangzhou Xiangfu Wood Pulp Fiber Manufacturing Co., Ltd., with an average length of 4.1 mm.

[0035] The lyocell fiber was purchased from Henan Hengtong Lyocell Fiber Technology Co., Ltd., with a specification of 1.6D and a fiber length of 10.4mm.

[0036] Preparation of biodegradable wood pulp spunlace nonwoven materials

[0037] Example 1

[0038] 1) Add water to 1 kg of wood pulp fiber for pulping treatment, 47.5°SR, pulping concentration 5wt%, pulping wet weight controlled at 9.0g, dry to obtain wood pulp fiber oven-dry pulp for later use.

[0039] 2) Disperse the oven-dry wood pulp fiber in 80 kg of anhydrous dichloromethane, sonicate at 800 W for 10 min, add 0.07 kg of 2-thiophene acetyl chloride and 0.119 kg of triethylamine, mix evenly, and react at 20 °C for 5 h. After the reaction is complete, filter, wash with water until neutral, and dry to obtain surface-modified wood pulp fiber.

[0040] 3) Under a nitrogen atmosphere, the surface-modified wood pulp fiber was immersed in 100 kg of anhydrous chloroform and sonicated at 800 W for 10 min. 0.15 kg of 3-thiophene methanol was added and mixed evenly. Then, 0.003 L of a catalytic oxidant solution with a concentration of 2 mol / L, which was a mixture of FeCl3 and chloroform, was added dropwise over 0.5 h. The reaction was then carried out at 30 °C for 12 h. After the reaction was completed, the mixture was filtered, washed three times alternately with ethanol and water, and dried at 80 °C to constant weight to obtain modified wood pulp fiber.

[0041] 4) Take 700g of modified wood pulp fiber and 300g of lyocell fiber from step 3), open and mix them to prepare a mixed pulp with a concentration of 0.4g / L. Pump the mixed pulp into an inclined wire forming system, output a wet-laid fiber web, perform hydroentangling reinforcement on a flat web, and then perform rotary drum hydroentangling reinforcement. Remove excess water using a suction device, dry at 110℃ for 10s, and wind to obtain a basis weight of 65g / m². 2 .

[0042] The flat web hydroentangling reinforcement process involves water needles perpendicular to the fiber web, with the first hydroentangling pressure at 60 bar, the second at 70 bar, and the third at 80 bar, and the water needle hole diameter at 0.12 mm. The rotary drum hydroentangling reinforcement process uses a hydroentangling pressure of 50 bar, a water needle hole diameter of 0.12 mm, a conveyor belt speed of 15 m / min, and a hydroentangling distance of 40 mm.

[0043] Example 2

[0044] The rest is the same as in Example 1, except that the amount of 2-thiophene acetyl chloride used in step 2) is 0.05 kg.

[0045] Example 3

[0046] The rest is the same as in Example 1, except that in step 3), 3-thiophene methanol is replaced with an equal mass of 2-(3-thiophene)ethanol.

[0047] Example 4

[0048] The rest is the same as in Example 1, except that in step 3), 3-thiophene methanol is replaced with an equal mass of 1-(thiophene-3-yl)ethanol.

[0049] Example 5

[0050] The rest is the same as in Example 1, except that the amount of 3-thiophene methanol used in step 3) is 0.135 kg.

[0051] Example 6

[0052] The rest is the same as in Example 1, except that the amount of 3-thiophene methanol used in step 3) is 0.08 kg.

[0053] Example 7

[0054] The rest is the same as in Example 1, except that the amount of 3-thiophene methanol used in step 3) is 0.20 kg.

[0055] Example 8

[0056] The rest is the same as in Example 1, except that in step 4), 600g of modified wood pulp fiber and 400g of lyocell fiber from step 3) are opened and mixed to prepare a mixed pulp with a concentration of 0.6g / L. The mixed pulp is pumped into an inclined wire forming system, output as a wet-laid fiber web, reinforced with a flat wire by hydroentangling, reinforced with a rotary drum by hydroentangling, and excess water is removed by a suction device. The web is dried at 110°C for 10s and wound to obtain a basis weight of 69g / m². 2 .

[0057] The flat web hydroentangling reinforcement process involves water needles perpendicular to the fiber web, with the first hydroentangling pressure at 60 bar, the second at 70 bar, and the third at 80 bar, and the water needle hole diameter at 0.12 mm. The rotary drum hydroentangling reinforcement process uses a hydroentangling pressure of 30 bar, a water needle hole diameter of 0.12 mm, a conveyor belt speed of 15 m / min, and a hydroentangling distance of 40 mm.

[0058] Comparative Example 1

[0059] The rest is the same as in Example 1, except that steps 2) and 3) are omitted.

[0060] 1) Add water to 1 kg of wood pulp fiber for pulping treatment, 47.5°SR, pulping concentration 5wt%, pulping wet weight controlled at 9.0g, dry to obtain wood pulp fiber oven-dry pulp for later use.

[0061] 2) Take 700g of wood pulp fiber and 300g of lyocell fiber, open and mix them to prepare a mixed pulp with a concentration of 0.4g / L. Pump the mixed pulp into an inclined wire forming system, output a wet-laid fiber web, perform hydroentangling reinforcement on a flat web, and then perform rotary drum hydroentangling reinforcement. Remove excess water through a suction device, dry at 110℃ for 10s, and wind to obtain a basis weight of 63g / m².2 The flat web hydroentangling reinforcement process involves: hydroentangling needles perpendicular to the fiber web, hydroentangling pressure of 80 bar, hydroentangling needle hole diameter of 0.12 mm, and 3 hydroentangling passes. The rotary drum hydroentangling reinforcement process involves: hydroentangling pressure of 50 bar, hydroentangling needle hole diameter of 0.12 mm, conveyor speed of 15 m / min, and hydroentangling distance of 40 mm.

[0062] Comparative Example 2

[0063] The rest is the same as in Example 1, except that step 1) is omitted, i.e.:

[0064] 1) Disperse wood pulp fibers in 80 kg of anhydrous dichloromethane, sonicate at 800 W for 10 min, add 0.07 kg of 2-thiophene acetyl chloride and 0.119 kg of triethylamine and mix evenly. Control the temperature at 20 °C and react for 5 h. After the reaction is completed, filter, wash with water until neutral, and dry to obtain surface-modified wood pulp fibers.

[0065] 2) Under a nitrogen atmosphere, the surface-modified wood pulp fiber was immersed in 100 kg of anhydrous chloroform and sonicated at 800 W for 10 min. 0.15 kg of 3-thiophene methanol was added and mixed evenly. Then, 0.003 L of a catalytic oxidant solution with a concentration of 2 mol / L, which was a mixture of FeCl3 and chloroform, was added dropwise over 0.5 h. The reaction was then carried out at 30 °C for 12 h. After the reaction was completed, the mixture was filtered, washed three times alternately with ethanol and water, and dried at 80 °C to constant weight to obtain modified wood pulp fiber.

[0066] 3) Take 700g of modified wood pulp fiber and 300g of lyocell fiber from step 2), open and mix them to prepare a mixed pulp with a concentration of 0.4g / L. Pump the mixed pulp into an inclined wire forming system, output a wet-laid fiber web, perform hydroentangling reinforcement on a flat web, and then perform rotary drum hydroentangling reinforcement. Remove excess water using a suction device, dry at 110℃ for 10s, and wind to obtain a basis weight of 66g / m². 2 .

[0067] The flat web hydroentangling reinforcement process involves water needles perpendicular to the fiber web, with the first hydroentangling pressure at 60 bar, the second at 70 bar, and the third at 80 bar, and the water needle hole diameter at 0.12 mm. The rotary drum hydroentangling reinforcement process uses a hydroentangling pressure of 50 bar, a water needle hole diameter of 0.12 mm, a conveyor belt speed of 15 m / min, and a hydroentangling distance of 40 mm.

[0068] The nonwoven materials prepared in the above embodiments and comparative examples were subjected to the following performance tests:

[0069] Water absorption: Water absorption is determined by the percentage change in weight before and after water absorption. The sample is cut into 100mm × 100mm pieces, weighed, and the weight of the sample is recorded as W0. The sample is placed in a beaker containing distilled water and left to stand for 1 minute. The sample is then removed from the distilled water and hung vertically for 3 minutes, and the weight is recorded as W1. The formula for calculating the water absorption rate W of the sample is as follows:

[0070] W = (W1 - W0) × 100%

[0071] Wet tensile strength: According to standard GB / T 24328.3-2020 Determination of tensile strength, elongation at maximum force and tensile energy absorption of toilet paper and its products, the sample was bent into a ring and immersed in distilled water or deionized water for 5 minutes. After taking it out, the surface water was gently wiped off with filter paper. The sample size was 50mm×150mm, the tensile clamping distance was 100mm, the tensile rate was 50mm / min, and the test environment temperature was 20℃ and the humidity was 65%RH.

[0072] Chip shedding: Under a load of 9 kPa, the sample and abrasive were subjected to planar friction in a Lissajous figure pattern. The instrument used was a YG401E Martindale apparatus. After 600 cycles, the sample was removed, and the chip shedding rate was calculated using the following formula:

[0073] D = (M - M1) / M × 100%

[0074] D - Shedding rate, %; M1 - Mass of the sample after friction, g; M - Original mass of the sample, g.

[0075] Table 1 Performance Test Results

[0076]

[0077] As can be seen from Table 1, the nonwoven fabric prepared by wet web forming and hydroentangling reinforcement process using modified wood pulp fiber and lyocell fiber as raw materials not only overcomes the high shedding rate caused by wood pulp fiber, but also endows the nonwoven fabric with excellent water absorption and wet tensile strength.

[0078] Examples 1, 6 and 7 show that the amount of 3-thiophene methanol has a significant effect on the shedding rate of nonwoven fabrics. It is speculated that in the dry state, the grafted polythiophene molecular chains tend to fold themselves and are difficult to form hydrogen bonds or entanglements with other fiber surface groups, resulting in weak cohesion between fibers. The preferred amount of 3-thiophene methanol is 13.5-15 wt% of wood pulp fiber.

[0079] Furthermore, it can be seen from Example 1 and Comparative Examples 1-2 that pulping treatment and modification treatment of wood pulp fibers have a synergistic effect in reducing the shedding rate.

[0080] The above detailed description is a specific description of one of the feasible embodiments of the present invention. This embodiment is not intended to limit the patent scope of the present invention. All equivalent implementations or modifications that do not depart from the present invention should be included within the scope of the technical solution of the present invention.

Claims

1. A biodegradable wood pulp hydroentangled nonwoven material, characterized in that, The raw materials include: 60-70 wt% modified wood pulp fiber and 30-40 wt% lyocell fiber. The modified wood pulp fiber is prepared by first treating the wood pulp fiber with a pulping process, then modifying its surface with a thiophene chloride derivative, and finally reacting it in situ on the modified wood pulp fiber with FeCl3 as a catalyst oxidant and hydroxythiophene derivative as a polymer monomer.

2. The biodegradable wood pulp hydroentangled nonwoven material according to claim 1, characterized in that, The amount of the thiophene chloride derivative is 5-7 wt% of the wood pulp fiber, and the amount of the hydroxythiophene derivative is 13.5-15 wt% of the wood pulp fiber.

3. The biodegradable wood pulp hydroentangled nonwoven material according to claim 1, characterized in that, The thiophene chloride derivative is selected from one or a combination of two or more of 3-thiophene carboxyl chloride, thiophene-3-yl-acetyl chloride, 2-thiophene carboxyl chloride, and 2-thiophene acetyl chloride.

4. The biodegradable wood pulp hydroentangled nonwoven material according to claim 1, characterized in that, The hydroxythiophene derivative is selected from one or a combination of two or more of 3-thiophene methanol, 1-(thiophene-3-yl)ethanol, 2-(3-thiophene)ethanol, and thiophene-3-ol.

5. The biodegradable wood pulp hydroentangled nonwoven material according to claim 4, characterized in that, The hydroxythiophene derivative is selected from one or a combination of two of 3-thiophene methanol and 2-(3-thiophene)ethanol.

6. The biodegradable wood pulp hydroentangled nonwoven material according to claim 5, characterized in that, The lyocell fiber has a specification of 0.9-3.0D and a length of 5-12mm; the wood pulp fiber has a length of 2-8mm; the wood pulp fiber is selected from one or a combination of two types of softwood pulp fiber and hardwood pulp fiber.

7. The biodegradable wood pulp hydroentangled nonwoven material according to claim 1, characterized in that, The modified wood pulp fiber is prepared by a method comprising the following steps: 1) Add water to the wood pulp fiber for pulping treatment, dry it, and obtain oven-dry wood pulp fiber for later use; 2) Disperse the oven-dry wood pulp fiber in an anhydrous organic solvent, sonicate, add thiophene chloride derivative and acid binder, mix evenly, and carry out the reaction under controlled temperature. After the reaction is completed, filter, wash and dry to obtain surface-modified wood pulp fiber. 3) Under an inert atmosphere, the surface-modified wood pulp fiber is immersed in an anhydrous organic solvent, sonicated, and hydroxythiophene derivative is added. After mixing evenly, a catalytic oxidant solution is added dropwise, and the reaction is carried out under controlled temperature. After the reaction is completed, the fiber is filtered, washed, and dried to obtain modified wood pulp fiber.

8. The biodegradable wood pulp hydroentangled nonwoven material according to claim 7, characterized in that, Step 2) The organic solvent is selected from one or a combination of two or more of dichloromethane, methyl isobutyl ketone, tetrahydrofuran, ethyl acetate, and chloroform; the ultrasonic power is 500-1500W, and the ultrasonic time is 5-30min; the mass ratio of wood pulp fiber to anhydrous organic solvent is 1:80-100.

9. The biodegradable wood pulp hydroentangled nonwoven material according to claim 7, characterized in that, Step 3) The organic solvent is selected from one or a combination of two or more of dichloromethane, methyl isobutyl ketone, tetrahydrofuran, ethyl acetate, and chloroform; the mass ratio of the surface-modified wood pulp fiber to the anhydrous organic solvent is 1:80-100; the ultrasonic power is 500-1500W, and the ultrasonic time is 5-30min; the catalytic oxidant solution is a mixture of FeCl3 and the organic solvent, the FeCl3 concentration in the catalytic oxidant solution is 2-4mol / L, and the catalytic oxidant solution is added dropwise over 0.5-1h; the molar ratio of the catalytic oxidant to the hydroxythiophene derivative is 4-6:1; the temperature is controlled at 20-30℃, and the reaction time is 10-18h; the washing is performed by alternating washing with ethanol and water 1-3 times; the drying temperature is 60-100℃.

10. A method for preparing a biodegradable wood pulp hydroentangled nonwoven material according to any one of claims 1-9, characterized in that, Includes the following steps: Modified wood pulp fibers and lyocell fibers are opened and mixed to prepare a mixed pulp. The mixed pulp is pumped to an inclined wire forming system to output a wet fiber web. The web is then hydroentangled and reinforced on a flat web, hydroentangled and reinforced on a rotary drum, dehydrated, dried, and wound.

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