A superabsorbent nonwoven material based on hot air assisted spinning and a method of making the same

Abstract

The present application relates to the technical field of high polymer materials, in particular to a super water-absorbing non-woven material based on hot air assisted spinning and a preparation method thereof.The super water-absorbing non-woven material prepared by the present application has internal fibers in the micro-nano scale, and the diameter distribution and fiber morphology can be precisely controlled.The material has high porosity, and the internal fibers have a three-dimensional curly structure, which can accelerate the penetration and diffusion of liquid in the material and the transmission rate between fibers, effectively improve the overall liquid absorption rate, optimize the internal liquid locking performance, have high liquid absorption rate and wider application scenarios, and the introduced antibacterial monomer has guanidine group and imidazole group structure, which can inhibit the activity of common pathogenic bacteria such as staphylococcus aureus, and finally realize the improvement of the antibacterial property of the material.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, specifically to a superabsorbent nonwoven material based on hot air assisted spinning and its preparation method. Background Technology

[0002] Superabsorbent nonwoven materials are advanced functional materials formed by the self-bonding and reinforcement of superabsorbent fibers. Compared with traditional absorbent materials (such as cotton, wool, and sponges), they exhibit significant advantages in terms of absorption rate, absorption capacity, water retention, and applicability, and have therefore been widely used in the medical, hygiene, and agricultural and forestry fields in Europe, America, Japan, and South Korea. However, when this material is used in hygiene products, the warm, humid, and organic-rich microenvironment created during use provides ideal conditions for the rapid proliferation of bacteria, fungi, and other microorganisms. The proliferation of microorganisms can not only irritate the skin and increase the risk of infection, but their metabolic processes can also produce unpleasant odors, seriously affecting the user experience and personal hygiene. Therefore, it is necessary to enhance the antibacterial properties of these superabsorbent materials. Summary of the Invention

[0003] The purpose of this invention is to provide a superabsorbent nonwoven material based on hot air assisted spinning and its preparation method, so as to solve the problem of insufficient antibacterial ability of conventional absorbent materials.

[0004] To solve the above-mentioned technical problems, the present invention provides the following technical solution: In a first aspect, a method for preparing a superabsorbent nonwoven material based on hot air-assisted spinning includes the following steps: S1. Preparation of antibacterial monomers; S11. Imidazole-4,5-dicarboxylic acid, methacrylamide, and p-hydroxyanisole were added to DMF, cooled to a constant temperature in an ice-water bath, and stirred until homogeneous. Then, EDC·HCl, 1-hydroxybenzotriazole, and triethylamine were added and dispersed until homogeneous. The temperature was raised to 25-30°C, and the reaction was stirred for 6-8 hours. Deionized water was added to the reaction system to terminate the reaction, and the mixture was filtered. The filter cake was collected, washed with deionized water, and dried to obtain the imidazole intermediate. S12. Disperse the imidazole intermediate and p-hydroxyanisole in DMF, mix well, add EDC·HCl and 1-hydroxybenzotriazole, mix well, cool to constant temperature in an ice-water bath, add ethylenediamine dropwise, after the addition is complete, raise the temperature to 25~35℃, stir the reaction for 8~12h, add deionized water to the reaction system again to terminate the reaction and filter, collect the filter cake, wash with deionized water, dry, and obtain aminoimidazolium intermediate; S13. The aminoimidazole intermediate and p-hydroxyanisole were dispersed in an ethanol aqueous solution and stirred until homogeneous. Sodium hydroxide solution was added dropwise to adjust the pH of the reaction system to 9-9.5. O-methylisourea sulfate was then added, and the temperature was raised to 40-45℃. The reaction was carried out in the dark for 8-12 hours. Heating was then stopped, and hydrochloric acid was added dropwise to adjust the pH of the reaction system to neutral. The mixture was then filtered, washed, and dried to obtain the antibacterial monomer. S2. Under ice-water bath conditions, acrylic acid was added to sodium hydroxide solution for neutralization reaction, and then antibacterial monomer and acrylamide were added and mixed evenly to obtain a superabsorbent monomer solution. S3. Under nitrogen atmosphere protection, the polyvinyl alcohol aqueous solution and the superabsorbent monomer solution are mixed, heated to 40~50℃, stirred evenly, and then the initiator is added. The temperature is raised again to 65~75℃, and the reaction is stirred for 1~2 hours. The temperature is raised again to 80~85℃, and the reaction is stirred for 30~35 minutes. The heating is stopped, and after the reaction system is cooled to 55~65℃, the aldehyde crosslinking agent is added. After mixing evenly, the mixture is cooled to room temperature to obtain the superabsorbent polymer spinning solution. S4. The superabsorbent polymer spinning solution is loaded into a syringe, the syringe is connected to a multi-hole spinneret and placed in a micro pump, hot air-assisted air-jet spinning is performed, and the resulting material is placed in a vacuum environment for thermal cross-linking to obtain a superabsorbent nonwoven material.

[0005] Further, in step S11, the amounts of each component added, by weight, are 1 part imidazole-4,5-dicarboxylic acid, 0.55~0.59 parts methacrylamide, 0.005~0.008 parts p-hydroxyanisole, 25~35 parts DMF, 1.4~1.6 parts EDC·HCl, 0.9~1.1 parts 1-hydroxybenzotriazole and 0.8~1 parts triethylamine.

[0006] Further, in step S12, the amounts of each component added, by weight, are 1 part imidazole intermediate, 0.004~0.005 parts p-hydroxyanisole, 20~25 parts DMF, 1.05~1.15 parts EDC·HCl, 0.75~0.8 parts 1-hydroxybenzotriazole and 0.26~0.28 parts ethylenediamine.

[0007] Further, in step S13, the amounts of each component added, by weight, are 1 part of aminoimidazole intermediate, 0.004~0.005 parts of p-hydroxyanisole, 35~40 parts of ethanol aqueous solution, and 0.7~0.8 parts of O-methylisourea sulfate. The ethanol-water solution is a mixture of deionized water and anhydrous ethanol in a volume ratio of 1:1.

[0008] Further, in step S2, the concentration of the sodium hydroxide solution is 15-20 wt%, and the neutralization reaction time is 10-20 min; by weight, the amount of each component added is 2-3 parts acrylic acid, 1 part sodium hydroxide, 0.3-0.8 parts antibacterial monomer, and 0.8-1 part acrylamide.

[0009] Furthermore, in step S3, the amount of each component added, by weight, is 1-2 parts of polyvinyl alcohol aqueous solution, 1 part of superabsorbent monomer solution, 0.002-0.005 parts of initiator, and 0.01-0.02 parts of aldehyde crosslinking agent; In the polyvinyl alcohol aqueous solution, the degree of polymerization of polyvinyl alcohol is 2000-3000, and the degree of alcoholysis is 80-98%. The initiator is either potassium persulfate or ammonium persulfate; the aldehyde crosslinking agent is either glyoxal, malondialdehyde, succinaldehyde, or glutaraldehyde.

[0010] Furthermore, in step S4, during hot air-assisted air-jet spinning, the single-hole advance rate of air-jet spinning is 2~8 ml / h, the air pressure range is 0.1~0.3 MPa, and the temperature of the hot air-assisted airflow is 100~120℃.

[0011] Furthermore, in step S4, the thermal crosslinking temperature is 115~120℃, and the thermal crosslinking time is 25~35min.

[0012] Furthermore, in step S4, the fiber diameter distribution of the superabsorbent nonwoven material is 0.5~5μm.

[0013] Secondly, the present invention also provides a superabsorbent nonwoven material, which is prepared by the above-described preparation method.

[0014] Compared with the prior art, the beneficial effects achieved by the present invention are: The superabsorbent nonwoven material prepared by this invention has internal fibers at the micro-nano scale, and the diameter distribution and morphology of the fibers can be precisely controlled. The material has high porosity, and the internal fibers have a three-dimensional coiled structure, which can accelerate the penetration and diffusion of liquid inside the material and the transport rate between fibers, effectively improving the overall liquid absorption rate, optimizing the internal liquid lock-in performance, and combining high liquid absorption ratio with a wider range of applicable scenarios.

[0015] This invention relies on the precise control of parameters such as hot air-assisted airflow temperature, airflow pressure, and spinning feed rate to achieve precise control over fiber morphology and material bulkiness. Addressing the problems of low areal density, insufficient structural bulkiness, and limited production efficiency in traditional electrospun products, this process enables the large-scale production of high areal density, high bulkiness, and superabsorbent nonwoven materials, while also possessing the technical advantages of low energy consumption and simple equipment structure.

[0016] Furthermore, based on this, the present invention adds antibacterial monomer materials to provide the product with excellent antibacterial properties. The present invention first uses imidazole-4,5-dicarboxylic acid to react with methacrylamide to synthesize an imidazole intermediate containing a double bond and an imidazole ring structure. Then, it is mixed with ethylenediamine to introduce an amino group, and then reacted with O-methylisourea sulfate to guanidinate, thereby preparing an antibacterial monomer with a guanidino group and an imidazole group structure. The double bond can participate in the polymerization process of monomers such as acrylamide, thereby participating in the polymerization and spinning of superabsorbent nonwoven materials, and finally achieving the improvement of the antibacterial properties of the material. Attached Figure Description

[0017] Figure 1 This is a physical image of the product of Embodiment 1 of the present invention; Figure 2 This is a photograph of the product after water absorption in Embodiment 1 of the present invention; Figure 3 This is a SEM image of the product of Embodiment 1 of the present invention; Figure 4 This is a SEM image of the product of Comparative Example 1 of this invention; Figure 5 This is a SEM image of the product of Comparative Example 2 of this invention; Figure 6 These are actual photos of the products of Embodiment 1, Comparative Example 1, and Comparative Example 2 of the present invention before thermal cross-linking. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Example 1. A method for preparing a superabsorbent nonwoven material based on hot air assisted spinning, comprising the following steps: S1. Preparation of antibacterial monomers; S11. Imidazole-4,5-dicarboxylic acid, methacrylamide, and p-hydroxyanisole were added to DMF, cooled to a constant temperature in an ice-water bath, and stirred until homogeneous. Then, EDC·HCl, 1-hydroxybenzotriazole, and triethylamine were added and dispersed until homogeneous. The temperature was raised to 25°C, and the reaction was stirred for 8 hours. Deionized water was added to the reaction system to terminate the reaction and the mixture was filtered. The filter cake was collected, washed with deionized water, and dried to obtain the imidazole intermediate. The amounts of each component added, by weight, are as follows: 1 part imidazole-4,5-dicarboxylic acid, 0.55 parts methacrylamide, 0.005 parts p-hydroxyanisole, 30 parts DMF, 1.4 parts EDC·HCl, 0.9 parts 1-hydroxybenzotriazole, and 0.8 parts triethylamine. S12. The imidazole intermediate and p-hydroxyanisole were dispersed in DMF and mixed evenly. EDC·HCl and 1-hydroxybenzotriazole were added and mixed evenly. The mixture was cooled to a constant temperature in an ice-water bath. Ethylenediamine was added dropwise. After the addition was complete, the temperature was raised to 25°C and the reaction was stirred for 12 hours. Deionized water was added to the reaction system again to terminate the reaction and the mixture was filtered. The filter cake was collected, washed with deionized water, and dried to obtain the aminoimidazolium intermediate. The amounts of each component added, by weight, are 1 part imidazole intermediate, 0.004 parts p-hydroxyanisole, 25 parts DMF, 1.05 parts EDC·HCl, 0.75 parts 1-hydroxybenzotriazole, and 0.26 parts ethylenediamine. S13. The aminoimidazole intermediate and p-hydroxyanisole were dispersed in an ethanol aqueous solution and stirred until homogeneous. Sodium hydroxide solution was added dropwise to adjust the pH of the reaction system to 9-9.5. O-methylisourea sulfate was then added, the temperature was raised to 40°C, and the reaction was carried out in the dark for 12 hours. Heating was then stopped, and hydrochloric acid was added dropwise to adjust the pH of the reaction system to neutral. The mixture was then filtered, washed, and dried to obtain the antibacterial monomer. The amounts of each component added were 1 part aminoimidazole intermediate, 0.004 parts p-hydroxyanisole, 40 parts ethanol aqueous solution, and 0.7 parts O-methylisourea sulfate, respectively. The ethanol-water solution is a mixture of deionized water and anhydrous ethanol in a volume ratio of 1:1. S2. Under ice-water bath conditions, sodium hydroxide and deionized water were mixed to prepare a sodium hydroxide solution with a concentration of 15wt%. Acrylic acid was added to the sodium hydroxide solution for neutralization reaction. Then, antibacterial monomer and acrylamide were added to the solution and mixed evenly to obtain a superabsorbent monomer solution. The components added, by weight, are 2 parts acrylic acid, 1 part sodium hydroxide, 5.67 parts deionized water, 0.3 parts antibacterial monomer, and 0.8 parts acrylamide. S3. Under nitrogen atmosphere protection, polyvinyl alcohol aqueous solution and superabsorbent monomer solution were mixed, heated to 40°C, stirred evenly, initiator was added, heated again to 65°C, stirred for 2 hours, heated again to 80°C, stirred for 35 minutes, heating was stopped, and after the reaction system cooled to 60°C, aldehyde crosslinking agent was added, mixed evenly, and cooled to room temperature to obtain superabsorbent polymer spinning solution. Its viscosity was tested and found to be 3.3 Pa·s. The components, by weight, are 2 parts polyvinyl alcohol aqueous solution, 1 part superabsorbent monomer solution, 0.002 parts initiator, and 0.01 parts aldehyde crosslinking agent. S4. The superabsorbent polymer spinning solution is loaded into a syringe. A 50ml syringe containing the superabsorbent spinning solution is placed into a micro-pump, with the syringe directly connected to a multi-hole spinneret. The single-hole feed rate is set to 4ml / h. A metal needle with an inner diameter of 0.5mm is selected, and the distance between the needle and the receiver is 35cm. The temperature of the hot air auxiliary gas flow is adjusted to 120℃, and the gas pressure to 0.12MPa. The spinning solution is sprayed using a high-speed hot air flow, causing the fine stream to be stretched and the solvent to evaporate. The spun material is collected at the receiver and placed in a vacuum environment at 120℃ for thermal cross-linking for 30 minutes. After cooling to room temperature, the superabsorbent nonwoven material is obtained.

[0020] Example 2. A method for preparing a superabsorbent nonwoven material based on hot air assisted spinning, comprising the following steps: S1. Preparation of antibacterial monomers; S11. Imidazole-4,5-dicarboxylic acid, methacrylamide, and p-hydroxyanisole were added to DMF, cooled to a constant temperature in an ice-water bath, and stirred until homogeneous. Then, EDC·HCl, 1-hydroxybenzotriazole, and triethylamine were added and dispersed until homogeneous. The temperature was raised to 30°C, and the reaction was stirred for 6 hours. Deionized water was added to the reaction system to terminate the reaction and the mixture was filtered. The filter cake was collected, washed with deionized water, and dried to obtain the imidazole intermediate. The amounts of each component added, by weight, are as follows: 1 part imidazole-4,5-dicarboxylic acid, 0.59 parts methacrylamide, 0.008 parts p-hydroxyanisole, 30 parts DMF, 1.6 parts EDC·HCl, 1.1 parts 1-hydroxybenzotriazole and 1 part triethylamine. S12. The imidazole intermediate and p-hydroxyanisole were dispersed in DMF and mixed evenly. EDC·HCl and 1-hydroxybenzotriazole were added and mixed evenly. The mixture was cooled to a constant temperature in an ice-water bath. Ethylenediamine was added dropwise. After the addition was complete, the temperature was raised to 35°C and the reaction was stirred for 8 hours. Deionized water was added to the reaction system again to terminate the reaction and the mixture was filtered. The filter cake was collected, washed with deionized water, and dried to obtain the aminoimidazolium intermediate. The amounts of each component added, by weight, are 1 part imidazole intermediate, 0.005 parts p-hydroxyanisole, 25 parts DMF, 1.15 parts EDC·HCl, 0.8 parts 1-hydroxybenzotriazole, and 0.28 parts ethylenediamine. S13. The aminoimidazole intermediate and p-hydroxyanisole were dispersed in an ethanol aqueous solution and stirred until homogeneous. Sodium hydroxide solution was added dropwise to adjust the pH of the reaction system to 9-9.5. O-methylisourea sulfate was then added, the temperature was raised to 45°C, and the reaction was carried out in the dark for 8 hours. Heating was then stopped, and hydrochloric acid was added dropwise to adjust the pH of the reaction system to neutral. The mixture was then filtered, washed, and dried to obtain the antibacterial monomer. The amounts of each component added, by weight, are 1 part aminoimidazole intermediate, 0.005 parts p-hydroxyanisole, 40 parts ethanol aqueous solution, and 0.7 parts O-methylisourea sulfate. The ethanol-water solution is a mixture of deionized water and anhydrous ethanol in a volume ratio of 1:1. S2. Under ice-water bath conditions, sodium hydroxide and deionized water were mixed to prepare a sodium hydroxide solution with a concentration of 15wt%. Acrylic acid was added to the sodium hydroxide solution for neutralization reaction. Then, antibacterial monomer and acrylamide were added to the solution and mixed evenly to obtain a superabsorbent monomer solution. The components added, by weight, are 2 parts acrylic acid, 1 part sodium hydroxide, 5.67 parts deionized water, 0.8 parts antibacterial monomer, and 0.8 parts acrylamide. S3. Under nitrogen atmosphere protection, the polyvinyl alcohol aqueous solution and the superabsorbent monomer solution were mixed, heated to 50°C, stirred evenly, and then the initiator was added. The temperature was raised to 75°C again, and the reaction was stirred for 1 hour. The temperature was raised to 85°C again, and the reaction was stirred for another 30 minutes. The heating was stopped, and after the reaction system cooled to 60°C, the aldehyde crosslinking agent was added. After mixing evenly, the mixture was cooled to room temperature to obtain the superabsorbent polymer spinning solution. The viscosity was tested and found to be 3.6 Pa·s. The components, by weight, are 2 parts polyvinyl alcohol aqueous solution, 1 part superabsorbent monomer solution, 0.002 parts initiator, and 0.01 parts aldehyde crosslinking agent. S4. The superabsorbent polymer spinning solution is loaded into a syringe. A 50ml syringe containing the superabsorbent spinning solution is placed into a micro-pump, with the syringe directly connected to a multi-hole spinneret. The single-hole feed rate is set to 3ml / h. A metal needle with an inner diameter of 0.5mm is selected, and the distance between the needle and the receiver is 35cm. The temperature of the hot air auxiliary gas flow is adjusted to 110℃, and the gas pressure to 0.12MPa. The spinning solution is sprayed using a high-speed hot air flow, causing the fine stream to be stretched and the solvent to evaporate. The spun material is collected at the receiver and placed in a vacuum environment at 120℃ for 30 minutes for thermal cross-linking. After cooling to room temperature, the superabsorbent nonwoven material is obtained.

[0021] Example 3. A method for preparing a superabsorbent nonwoven material based on hot air assisted spinning, comprising the following steps: Compared with Example 1, this example changes some parameters in steps S3 and S4, while the parameters of the remaining steps are the same as in Example 1; S3. Under nitrogen atmosphere protection, polyvinyl alcohol aqueous solution and superabsorbent monomer solution were mixed, heated to 40°C, stirred evenly, initiator was added, heated again to 65°C, stirred for 2 hours, heated again to 80°C, stirred for 35 minutes, heating was stopped, and after the reaction system cooled to 60°C, aldehyde crosslinking agent was added, mixed evenly, and cooled to room temperature to obtain superabsorbent polymer spinning solution. Its viscosity was tested and found to be 6.9 Pa·s. The components, by weight, are 1 part polyvinyl alcohol aqueous solution, 1 part superabsorbent monomer solution, 0.002 parts initiator, and 0.01 parts aldehyde crosslinking agent. S4. The superabsorbent polymer spinning solution is loaded into a syringe. A 50ml syringe containing the superabsorbent spinning solution is placed into a micro-pump, with the syringe directly connected to a multi-hole spinneret. The single-hole feed rate is set to 3ml / h. A metal needle with an inner diameter of 0.5mm is selected, and the distance between the needle and the receiver is 35cm. The temperature of the hot air auxiliary gas flow is adjusted to 120℃, and the gas pressure to 0.12MPa. The spinning solution is sprayed using a high-speed hot air flow, causing the fine stream to be stretched and the solvent to evaporate. The spun material is collected at the receiver and placed in a vacuum environment at 120℃ for thermal cross-linking for 30 minutes. After cooling to room temperature, the superabsorbent nonwoven material is obtained.

[0022] Example 4. A method for preparing a superabsorbent nonwoven material based on hot air assisted spinning, comprising the following steps: Compared with Example 3, this example changes some parameters in steps S2 and S4, while the parameters of the remaining steps are the same as in Example 3; S2. Under ice-water bath conditions, sodium hydroxide and deionized water were mixed to prepare a sodium hydroxide solution with a concentration of 20wt%. Acrylic acid was added to the sodium hydroxide solution for neutralization reaction. Then, antibacterial monomer and acrylamide were added to the solution and mixed evenly to obtain a superabsorbent monomer solution. The components added, by weight, are 2 parts acrylic acid, 1 part sodium hydroxide, 4 parts deionized water, 0.3 parts antibacterial monomer, and 0.8 parts acrylamide. S3. Under nitrogen atmosphere protection, polyvinyl alcohol aqueous solution and superabsorbent monomer solution were mixed, heated to 40°C, stirred evenly, initiator was added, heated again to 65°C, stirred for 2 hours, heated again to 80°C, stirred for 35 minutes, heating was stopped, and after the reaction system cooled to 60°C, aldehyde crosslinking agent was added, mixed evenly, and cooled to room temperature to obtain superabsorbent polymer spinning solution. Its viscosity was tested and found to be 7.2 Pa·s. The components, by weight, are 1 part polyvinyl alcohol aqueous solution, 1 part superabsorbent monomer solution, 0.002 parts initiator, and 0.01 parts aldehyde crosslinking agent. S4. The superabsorbent polymer spinning solution is loaded into a syringe. A 50ml syringe containing the superabsorbent spinning solution is placed into a micro-pump, with the syringe directly connected to a multi-hole spinneret. The single-hole feed rate is set to 2.5ml / h. A metal needle with an inner diameter of 0.5mm is selected, and the distance between the needle and the receiver is 35cm. The temperature of the hot air auxiliary gas flow is adjusted to 110℃, and the gas pressure to 0.12MPa. The spinning solution is sprayed using a high-speed hot air flow, causing the fine stream to be stretched and the solvent to evaporate. The spun material is collected at the receiver and placed in a vacuum environment at 120℃ for 30 minutes for thermal cross-linking. After cooling to room temperature, the superabsorbent nonwoven material is obtained.

[0023] Example 5. A method for preparing a superabsorbent nonwoven material based on hot air assisted spinning, comprising the following steps: Compared with Example 4, this example changes some parameters in steps S3 and S4, while the parameters of the remaining steps are the same as in Example 4; S3. Under nitrogen atmosphere protection, the polyvinyl alcohol aqueous solution and the superabsorbent monomer solution were mixed, heated to 40°C, stirred evenly, and then the initiator was added. The temperature was raised to 65°C again, and the reaction was stirred for 2 hours. The temperature was raised to 80°C again, and the reaction was stirred for 35 minutes. The heating was stopped, and after the reaction system cooled to 60°C, the aldehyde crosslinking agent was added. After mixing evenly, the mixture was cooled to room temperature to obtain the superabsorbent polymer spinning solution. The viscosity was tested and found to be 10.0 Pa·s. The components, by weight, are 1 part polyvinyl alcohol aqueous solution, 1 part superabsorbent monomer solution, 0.005 parts initiator, and 0.02 parts aldehyde crosslinking agent. S4. The superabsorbent polymer spinning solution is loaded into a syringe. A 50ml syringe containing the superabsorbent spinning solution is placed into a micro-pump, with the syringe directly connected to a multi-hole spinneret. The single-hole feed rate is set to 3ml / h. A metal needle with an inner diameter of 0.5mm is selected, and the distance between the needle and the receiver is 35cm. The temperature of the hot air auxiliary gas flow is adjusted to 120℃, and the gas pressure to 0.15MPa. The spinning solution is sprayed using a high-speed hot air flow, causing the fine stream to be stretched and the solvent to evaporate. The spun material is collected at the receiver and placed in a vacuum environment at 120℃ for 30 minutes for thermal cross-linking. After cooling to room temperature, the superabsorbent nonwoven material is obtained.

[0024] Comparative Example 1. A method for preparing a superabsorbent nonwoven material based on hot air assisted spinning, comprising the following steps: Compared with Example 1, this comparative example did not use hot air-assisted spinning, and all other steps were the same as in Example 1; S4. Load the superabsorbent polymer spinning solution into a syringe, place the 50ml syringe containing the superabsorbent mixed spinning solution into a micro pump, connect the syringe to the multi-hole spinneret, set its single-hole injection rate to 4ml / h, select a metal needle with an inner diameter of 0.5mm, and a needle distance of 35cm from the receiver, collect the spinning material at the receiver, and place it in a vacuum environment at 120℃ for thermal crosslinking for 30min. After that, remove it and cool it to room temperature to obtain the superabsorbent nonwoven material.

[0025] Comparative Example 2. A method for preparing a superabsorbent nonwoven material based on hot air assisted spinning, comprising the following steps: Compared with Example 1, this comparative example changes the temperature of the hot air auxiliary airflow in step S4 to 60°C, while the other steps remain unchanged; S4. The superabsorbent polymer spinning solution is loaded into a syringe. A 50ml syringe containing the superabsorbent spinning solution is placed into a micro-pump, with the syringe directly connected to a multi-hole spinneret. The single-hole feed rate is set to 4ml / h. A metal needle with an inner diameter of 0.5mm is selected, and the distance between the needle and the receiver is 35cm. The temperature of the hot air auxiliary gas flow is adjusted to 60℃, and the gas pressure to 0.12MPa. The spinning solution is sprayed using a high-speed hot air flow, causing the fine stream to be stretched and the solvent to evaporate. The spun material is collected at the receiver and placed in a vacuum environment at 120℃ for 30 minutes for thermal cross-linking. After cooling to room temperature, the superabsorbent nonwoven material is obtained.

[0026] Comparative Example 3. A method for preparing a superabsorbent nonwoven material based on hot air assisted spinning, comprising the following steps: Compared with Example 1, this comparative example did not prepare an antibacterial monomer, but directly replaced it with an equal amount of acrylamide; S2. Under ice-water bath conditions, sodium hydroxide and deionized water were mixed to prepare a sodium hydroxide solution with a concentration of 15 wt%. Acrylic acid was added to the sodium hydroxide solution for neutralization and reaction. Acrylamide was then added to the solution and mixed evenly to obtain a superabsorbent monomer solution. The components added, by weight, are 2 parts acrylic acid, 1 part sodium hydroxide, 5.67 parts deionized water, and 1.1 parts acrylamide. S3. Under nitrogen atmosphere protection, polyvinyl alcohol aqueous solution and superabsorbent monomer solution were mixed, heated to 40°C, stirred evenly, initiator was added, heated again to 65°C, stirred for 2 hours, heated again to 80°C, stirred for 35 minutes, heating was stopped, and after the reaction system cooled to 60°C, aldehyde crosslinking agent was added, mixed evenly, and cooled to room temperature to obtain superabsorbent polymer spinning solution. Its viscosity was tested and found to be 3.3 Pa·s. The components, by weight, are 2 parts polyvinyl alcohol aqueous solution, 1 part superabsorbent monomer solution, 0.002 parts initiator, and 0.01 parts aldehyde crosslinking agent. S4. The superabsorbent polymer spinning solution is loaded into a syringe. A 50ml syringe containing the superabsorbent spinning solution is placed into a micro-pump, with the syringe directly connected to a multi-hole spinneret. The single-hole feed rate is set to 4ml / h. A metal needle with an inner diameter of 0.5mm is selected, and the distance between the needle and the receiver is 35cm. The temperature of the hot air auxiliary gas flow is adjusted to 120℃, and the gas pressure to 0.12MPa. The spinning solution is sprayed using a high-speed hot air flow, causing the fine stream to be stretched and the solvent to evaporate. The spun material is collected at the receiver and placed in a vacuum environment at 120℃ for thermal cross-linking for 30 minutes. After cooling to room temperature, the superabsorbent nonwoven material is obtained.

[0027] Testing: Weigh 0.1g of the superabsorbent nonwoven material products prepared in Examples 1-5 and Comparative Examples 1-3 respectively, place them in pure water to absorb water and let them stand for 2 hours, then take them out and test their pure water absorption ratio and the amount of backflow after 6 hours. Weigh 0.1g of the superabsorbent nonwoven material products prepared in Examples 1-5 and Comparative Examples 1-3 respectively, place them in 0.9% saline solution, and test their saline absorption ratio in 1 minute. The test results are shown in Table 1 below. Table 1.

[0028] The antibacterial properties of the superabsorbent nonwoven materials prepared in Examples 1, 2 and Comparative Example 3 were tested according to GB / T20944.3-2008. The test results are shown in Table 2 below. Table 2

[0029] SEM analysis was performed on the products of Example 1, Comparative Example 1, and Comparative Example 2, respectively. The results are shown in [Figure Number]. Figures 3-5 .

[0030] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a superabsorbent nonwoven material based on hot air-assisted spinning, characterized in that, Includes the following steps: S1. Preparation of antibacterial monomers; S11. Imidazole-4,5-dicarboxylic acid, methacrylamide, and p-hydroxyanisole were added to DMF, cooled to a constant temperature in an ice-water bath, and stirred until homogeneous. Then, EDC·HCl, 1-hydroxybenzotriazole, and triethylamine were added and dispersed until homogeneous. The temperature was raised to 25-30°C, and the reaction was stirred for 6-8 hours. Deionized water was added to the reaction system to terminate the reaction, and the mixture was filtered. The filter cake was collected, washed with deionized water, and dried to obtain the imidazole intermediate. S12. Disperse the imidazole intermediate and p-hydroxyanisole in DMF, mix well, add EDC·HCl and 1-hydroxybenzotriazole, mix well, cool to constant temperature in an ice-water bath, add ethylenediamine dropwise, after the addition is complete, raise the temperature to 25~35℃, stir the reaction for 8~12h, add deionized water to the reaction system again to terminate the reaction and filter, collect the filter cake, wash with deionized water, dry, and obtain aminoimidazolium intermediate; S13. The aminoimidazole intermediate and p-hydroxyanisole were dispersed in an ethanol aqueous solution and stirred until homogeneous. Sodium hydroxide solution was added dropwise to adjust the pH of the reaction system to 9-9.

5. O-methylisourea sulfate was then added, and the temperature was raised to 40-45℃. The reaction was carried out in the dark for 8-12 hours. Heating was then stopped, and hydrochloric acid was added dropwise to adjust the pH of the reaction system to neutral. The mixture was then filtered, washed, and dried to obtain the antibacterial monomer. S2. Under ice-water bath conditions, acrylic acid was added to sodium hydroxide solution for neutralization reaction, and then antibacterial monomer and acrylamide were added and mixed evenly to obtain a superabsorbent monomer solution. S3. Under nitrogen atmosphere protection, the polyvinyl alcohol aqueous solution and the superabsorbent monomer solution are mixed, heated to 40~50℃, stirred evenly, and then the initiator is added. The temperature is raised again to 65~75℃, and the reaction is stirred for 1~2 hours. The temperature is raised again to 80~85℃, and the reaction is stirred for 30~35 minutes. The heating is stopped, and after the reaction system is cooled to 55~65℃, the aldehyde crosslinking agent is added. After mixing evenly, the mixture is cooled to room temperature to obtain the superabsorbent polymer spinning solution. S4. The superabsorbent polymer spinning solution is loaded into a syringe, the syringe is connected to a multi-hole spinneret and placed in a micro pump, hot air-assisted air-jet spinning is performed, and the resulting material is placed in a vacuum environment for thermal cross-linking to obtain a superabsorbent nonwoven material.

2. The method for preparing a superabsorbent nonwoven material based on hot air assisted spinning according to claim 1, characterized in that: In step S11, the amounts of each component added, by weight, are 1 part imidazole-4,5-dicarboxylic acid, 0.55~0.59 parts methacrylamide, 0.005~0.008 parts p-hydroxyanisole, 25~35 parts DMF, 1.4~1.6 parts EDC·HCl, 0.9~1.1 parts 1-hydroxybenzotriazole and 0.8~1 parts triethylamine.

3. The method for preparing a superabsorbent nonwoven material based on hot air assisted spinning according to claim 1, characterized in that: In step S12, the amounts of each component added, by weight, are 1 part imidazole intermediate, 0.004~0.005 parts p-hydroxyanisole, 20~25 parts DMF, 1.05~1.15 parts EDC·HCl, 0.75~0.8 parts 1-hydroxybenzotriazole and 0.26~0.28 parts ethylenediamine.

4. The method for preparing a superabsorbent nonwoven material based on hot air assisted spinning according to claim 1, characterized in that: In step S13, the amounts of each component added, by weight, are 1 part of aminoimidazole intermediate, 0.004 to 0.005 parts of p-hydroxyanisole, 35 to 40 parts of ethanol aqueous solution, and 0.7 to 0.8 parts of O-methylisourea sulfate. The ethanol-water solution is a mixture of deionized water and anhydrous ethanol in a volume ratio of 1:

1.

5. The method for preparing a superabsorbent nonwoven material based on hot air assisted spinning according to claim 1, characterized in that: In step S2, the concentration of the sodium hydroxide solution is 15-20 wt%, and the neutralization reaction time is 10-20 min; by weight, the amount of each component added is 2-3 parts acrylic acid, 1 part sodium hydroxide, 0.3-0.8 parts antibacterial monomer, and 0.8-1 part acrylamide.

6. The method for preparing a superabsorbent nonwoven material based on hot air assisted spinning according to claim 1, characterized in that: In step S3, the amount of each component added, by weight, is 1-2 parts of polyvinyl alcohol aqueous solution, 1 part of superabsorbent monomer solution, 0.002-0.005 parts of initiator, and 0.01-0.02 parts of aldehyde crosslinking agent; In the polyvinyl alcohol aqueous solution, the degree of polymerization of polyvinyl alcohol is 2000-3000, and the degree of alcoholysis is 80-98%. The initiator is either potassium persulfate or ammonium persulfate; the aldehyde crosslinking agent is either glyoxal, malondialdehyde, succinaldehyde, or glutaraldehyde.

7. The method for preparing a superabsorbent nonwoven material based on hot air assisted spinning according to claim 1, characterized in that: In step S4, during hot air-assisted air-jet spinning, the single-hole feed rate of air-jet spinning is 2~8 ml / h, the air pressure range is 0.1~0.3 MPa, and the hot air-assisted airflow temperature is 100~120℃.

8. The method for preparing a superabsorbent nonwoven material based on hot air assisted spinning according to claim 1, characterized in that: In step S4, the thermal crosslinking temperature is 115~120℃ and the thermal crosslinking time is 25~35min.

9. The method for preparing a superabsorbent nonwoven material based on hot air assisted spinning according to claim 1, characterized in that: In step S4, the fiber diameter distribution of the superabsorbent nonwoven material is 0.5~5μm.

10. A superabsorbent nonwoven material prepared by the preparation method according to any one of claims 1 to 9.

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