Cleaning towel cloth made of degradable material and preparation method of cleaning towel cloth

Abstract

The invention belongs to the technical field of cleaning cloth, and particularly relates to cleaning towel cloth made of a degradable material and a preparation method of the cleaning towel cloth. Uniformly mixing cellulose pulp, an N-methylmorpholine-N-oxide aqueous solution, the modification liquid and a fixing agent to obtain a fiber spinning solution, and preparing modified lyocell fibers by utilizing the fiber spinning solution; the modified lyocell fibers and cotton fibers are spun through compact spinning to obtain blended yarns, and then the blended yarns are used for weaving to obtain the cleaning towel cloth made of the degradable material. The modified liquid is prepared from the following raw materials: quaternized carboxymethyl chitosan, modified nano silicon dioxide, polyvinyl alcohol and deionized water; the cleaning towel cloth provided by the invention not only has relatively good water absorption performance, but also has excellent wear resistance, breaking strength and antibacterial performance, and also keeps good biodegradability at the same time.

Description

Technical Field

[0001] The invention belongs to the technical field of cleaning towels, and in particular relates to a cleaning towel made of a degradable material and a preparation method thereof. Background Art

[0002] Cleaning towels are a product widely used in daily life and industrial fields, and their performance requirements are high. First of all, cleaning towels need to have good water absorption in order to quickly absorb liquids; secondly, due to frequent friction and stretching during the cleaning process, cleaning towels need to have excellent wear resistance and breaking strength to ensure their service life; in addition, cleaning towels are prone to breeding bacteria during use, so antibacterial properties are also an important functional requirement. Traditional cleaning towels are mostly made of synthetic fibers or natural fibers. Although the former has excellent mechanical properties, it is non-degradable and has poor antibacterial properties; although the latter is degradable, its mechanical and antibacterial properties often cannot meet high-demand usage scenarios.

[0003] As a natural polymer material, cellulose has become an ideal choice to replace traditional synthetic fibers due to its wide sources, renewable and biodegradable properties. Among them, Lyocell is a new type of regenerated cellulose fiber made from cellulose by N-methylmorpholine-N-oxide (NMMO) solvent spinning. Lyocell fiber not only has the comfort and degradability of natural fibers, but also has the high strength and wear resistance of synthetic fibers, so it has been widely used in the textile field. However, traditional Lyocell fibers still have shortcomings in some properties, such as poor antibacterial properties, which limits its application in fields with high hygiene requirements such as cleaning products. In addition, although the breaking strength and wear resistance of pure Lyocell fibers are better than those of natural cotton fibers, they still need to be further improved in high-intensity usage scenarios.

[0004] As global environmental problems become increasingly severe, the research and development of biodegradable materials has become one of the hot topics in the current field of materials science. Traditional synthetic fiber materials, such as polyester and polyamide, have excellent mechanical properties and durability, but their non-degradability has led to serious environmental pollution problems. Especially in the field of disposable products, such as cleaning wipes and wet wipes, the waste generated after a large amount of use is difficult to degrade naturally, which has brought great pressure to the ecological environment. Therefore, it is urgent to develop a biodegradable fiber material with both excellent performance and environmental friendliness. Summary of the invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a cleaning towel made of a degradable material and a preparation method thereof, wherein cellulose pulp is combined with a functional modification liquid to prepare a modified lyocell fiber with excellent comprehensive performance, and the modified lyocell fiber is blended with cotton fiber, and a high-performance blended yarn is made using a concentrated spinning technology, and finally a degradable cleaning towel is woven. The cleaning towel not only retains the biodegradability of natural fibers, but also significantly improves its water absorption, wear resistance, breaking strength and antibacterial properties through functional modification, providing new ideas and technical support for the development of environmentally friendly high-performance cleaning products.

[0006] The technical solution adopted by the present invention to achieve the above-mentioned purpose is: A method for preparing a cleaning towel made of a degradable material comprises the following steps: Step S1: cellulose pulp, N-methylmorpholine-N-oxide aqueous solution, modifying liquid and fixing agent are uniformly mixed to obtain fiber spinning solution, and then the fiber spinning solution is added into a screw extruder and extruded into raw fibers through a spinneret, and the raw fibers are coagulated, alcohol washed, water washed, oiled and dried to obtain modified lyocell fibers; Step S2: spinning the modified lyocell fiber and the cotton fiber by conglomerate spinning to obtain a blended yarn, and then weaving the blended yarn; The modified solution in step S1 comprises the following raw materials in parts by weight: 5-10 parts of quaternized carboxymethyl chitosan, 0.5-1.5 parts of modified nano-silicon dioxide, 4-8 parts of polyvinyl alcohol, and 80-120 parts of deionized water; The preparation method of the modified nano silicon dioxide is: Under stirring conditions, citric acid is dispersed in anhydrous ethanol, and then 5,6-epoxyhexyltriethoxysilane is added, the temperature is raised to 60-80°C, the reaction is carried out for 6-8 hours, and then cooled to room temperature. Then, nano-silica sol and deionized water are added, and after ultrasonic dispersion, the reaction is continued at 50-70°C for 5-7 hours, cooled to room temperature, and post-treated to obtain modified nano-silica.

[0007] In order to overcome the limitations of lyocell fibers, the present invention modifies cellulose pulp, and its performance can be significantly improved by introducing functional additives and chemically modifying the fiber surface. Quaternized carboxymethyl chitosan, as a cationic polysaccharide, not only has good water solubility and film-forming properties, but also has excellent antibacterial properties. Its introduction into the fiber spinning solution can give it a lasting antibacterial function during the fiber forming process. In addition, nano-silica, as a common inorganic nanomaterial, is often used to enhance the mechanical properties of polymer materials due to its high specific surface area and excellent mechanical properties. By modifying the surface of nano-silica and introducing citric acid and 5,6-epoxyhexyltriethoxysilane, its compatibility with the cellulose matrix can be improved, thereby further improving the mechanical properties of the fiber.

[0008] On the basis of fiber modification, blending modified lyocell fiber with natural cotton fiber can combine the advantages of both and obtain blended yarn with more balanced performance. Cotton fiber, as a traditional natural fiber, has excellent hygroscopicity and comfort, but its strength and wear resistance are relatively low. By blending with modified lyocell fiber, it can not only make up for the mechanical property defects of cotton fiber, but also further improve the overall performance of blended yarn. As an advanced spinning process, concentrated spinning technology can effectively reduce yarn hairiness, improve yarn uniformity and strength, thus laying the foundation for the subsequent weaving of high-performance cleaning towels.

[0009] Furthermore, in the preparation process of modified nano-silica, the mass ratio of citric acid, 5,6-epoxyhexyltriethoxysilane, nano-silica sol and deionized water is 20:20-30:200-250:20-30, the volume ratio of anhydrous ethanol to deionized water is 20:5-15, the ultrasonic power during ultrasonic dispersion is 150-250W, and the ultrasonic time is 10-20min.

[0010] Furthermore, in step S1, the mass ratio of the cellulose pulp, the N-methylmorpholine-N-oxide aqueous solution, the modified liquid, and the fixing agent is 10-15:75:4-8:0.5-0.8; the preparation method of the modified liquid is: adding polyvinyl alcohol to deionized water, heating to 70-90°C, stirring until dissolved, then adding quaternized carboxymethyl chitosan, lowering the temperature to 50-70°C, stirring for 20-40 minutes, then adding modified nano-silica, ultrasonically treating for 10-20 minutes, continuing to stir at 50-70°C for 20-40 minutes, cooling and filtering to obtain the modified liquid.

[0011] Furthermore, the preparation method of the quaternized carboxymethyl chitosan is: under stirring conditions, dissolving carboxymethyl chitosan in deionized water, adding 2,3-epoxypropyltrimethylammonium chloride, raising the temperature to 50-70°C, reacting for 20-30 hours, cooling to room temperature, and post-treating to obtain quaternized carboxymethyl chitosan; the mass ratio of the carboxymethyl chitosan and 2,3-epoxypropyltrimethylammonium chloride is 10:1-2, and the mass volume ratio of the carboxymethyl chitosan to deionized water is 0.8-1.2 g / mL.

[0012] The cleaning towel made of degradable material provided by the present invention can also be subjected to anti-wrinkle treatment or pre-shrinkage treatment to further improve its comprehensive performance.

[0013] The present invention has the following beneficial effects: Lyocell fiber itself has certain degradability and good hygroscopicity. Cellulose pulp, as the main raw material of Lyocell fiber, is the basis for forming the fiber structure. N-methylmorpholine-N-oxide aqueous solution as a solvent helps to dissolve cellulose pulp and form a uniform spinning solution, providing conditions for subsequent fiber forming.

[0014] In the modified liquid, quaternized carboxymethyl chitosan plays multiple roles. Carboxymethyl chitosan itself has certain hydrophilicity and antibacterial properties, and the introduction of quaternary ammonium salt groups enhances its antibacterial properties. Quaternary ammonium salt groups are positively charged, and the surface of bacteria is usually negatively charged. Through electrostatic attraction, quaternized carboxymethyl chitosan can be adsorbed on the surface of bacteria, destroying the structure of the bacterial cell membrane, causing leakage of intracellular substances, thereby achieving an antibacterial effect. At the same time, its hydrophilicity helps to improve the overall water absorption of the fiber. In addition, quaternized carboxymethyl chitosan has good biocompatibility and degradability, and synergizes with raw materials such as cellulose pulp, which not only ensures the antibacterial and water absorption properties of the cleaning cloth, but also maintains its biodegradability. Modified nano-silica is also crucial. The introduction of citric acid on the surface of nano-silica particles increases the active sites and hydrophilicity of the surface, while the introduction of 5,6-epoxyhexyltriethoxysilane enables it to react chemically with fiber molecules better, enhances the compatibility and bonding force with the fiber, and enables the nano-silica particles to be evenly dispersed in the fiber, giving full play to the reinforcing effect. The nano-size effect of nano-silica particles can also effectively hinder the expansion of cracks inside the fiber, improve the wear resistance and breaking strength of the fiber, and the addition of modified nano-silica can significantly improve the wear resistance, breaking strength and water absorption of the cleaning towel. In addition, quaternized carboxymethyl chitosan and modified nano-silica can also combine with each other through electrostatic interaction or hydrogen bonding to form a synergistic network structure, further enhancing the mechanical properties and antibacterial properties of the fiber. Polyvinyl alcohol has good film-forming and bonding properties, and can better combine other raw materials in the system, thereby enhancing the interaction between fibers, which has a positive effect on the improvement of wear resistance and breaking strength, and it also has a certain hydrophilicity, which cooperates with other hydrophilic raw materials to further improve the water absorption of the product.

[0015] Cotton fiber has good natural water absorption and comfort. It is combined with modified lyocell fiber to form a blended yarn through concentrated spinning, and the two complement each other. The presence of cotton fiber increases the water absorption of the yarn, while the performance improvement characteristics of modified lyocell fiber give the blended yarn better wear resistance. During the weaving process, the structure formed by this blended yarn enables the cleaning towel to comprehensively reflect the excellent performance brought by each raw material, and ultimately makes the cleaning towel not only have good water absorption performance, but also excellent wear resistance, breaking strength, antibacterial properties, while maintaining good biodegradability. DETAILED DESCRIPTION

[0016] The following will be combined with the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of this application. The raw materials used in the following embodiments are all common commercially available products. Example 1

[0017] A method for preparing a cleaning towel made of a degradable material comprises the following steps: Step S1: uniformly mixing cellulose pulp, N-methylmorpholine-N-oxide aqueous solution, modifying liquid and fixing agent to obtain fiber spinning solution, then adding the fiber spinning solution into a screw extruder and extruding raw fibers through a spinneret, and the raw fibers are subjected to coagulation, alcohol washing, water washing, oiling and drying processes to obtain modified lyocell fibers; wherein the mass ratio of the cellulose pulp, N-methylmorpholine-N-oxide aqueous solution, modifying liquid and fixing agent is 13:75:6:0.7, the mass fraction of the N-methylmorpholine-N-oxide aqueous solution is 50%; the cellulose pulp is polymerized The hardwood pulp with a DP550 degree and a moisture regain of 7.2%; the fixing agent is triphenylmethane triisocyanate; the air gap length of the spinning system is 7 cm, the spinning speed is 40 m / min, the spinning temperature is 90°C, the spinneret aperture is 60 μm, the capillary length is 600 μm, the ejected silk thread is vertically stretched in the air, the spinneret draft ratio is 20, enters the coagulation bath, coagulates and forms, the coagulation bath concentration is 15wt% NMMO aqueous solution, and the coagulation bath temperature is 7°C; the processes of alcohol washing, water washing, oiling, drying, etc. can all be carried out by conventional techniques in the art; Step S2: spinning the modified lyocell fiber and the cotton fiber by aggregate spinning to obtain a blended yarn, and then using the blended yarn to weave a cleaning towel; wherein the fineness of the modified lyocell fiber and the cotton fiber are both 1.5 dtex, the length is both 34 mm, the mass ratio of the modified lyocell fiber to the cotton fiber during blending is 1:1, and the twist of the blended yarn is 35 twists / 10 cm; the blended yarn is used as the warp yarn and the weft yarn respectively to weave a plain fabric, the yarn count in English is controlled to be 80, the warp yarn density is 600 yarns / 10 cm, and the weft yarn density is 365 yarns / 10 cm; The modified solution in step S1 comprises the following raw materials in parts by weight: 8 parts of quaternized carboxymethyl chitosan, 1 part of modified nano-silicon dioxide, 6 parts of polyvinyl alcohol, and 100 parts of deionized water; The preparation method of the modified nano-silica is as follows: under stirring conditions, citric acid is dispersed in anhydrous ethanol, 5,6-epoxyhexyltriethoxysilane is added, the temperature is raised to 70°C, the reaction is performed for 7 hours, the reaction is naturally cooled to room temperature, and then nano-silica sol (solid content of 25%, average particle size of 86nm, pH of 8.9) and deionized water are added, the reaction is continued at 60°C for 6 hours after ultrasonic dispersion, the reaction is naturally cooled to room temperature, centrifuged, the precipitate is collected, and the precipitate is centrifuged and washed with anhydrous ethanol and deionized water in turn. The centrifugal speed in the above centrifugal process is 10,000 rpm, and the centrifugal time is 20 minutes. The washing step was performed for 10 minutes. After centrifugal washing, the mixture was vacuum dried at 60°C to constant weight. After grinding, the mixture was sieved through an 800-mesh sieve to obtain modified nano-silica. The mass ratio of citric acid, 5,6-epoxyhexyltriethoxysilane, nano-silica sol and deionized water was 20:25:230:25, the volume ratio of anhydrous ethanol to deionized water was 20:10, the ultrasonic power during ultrasonic dispersion was 200W, and the ultrasonic time was 15 minutes. The grinding process can be performed using conventional techniques in the art. The grafting rate of the modified nano-silica was measured to be 12.4% by thermogravimetric analysis. The preparation method of the quaternized carboxymethyl chitosan is as follows: under stirring conditions, carboxymethyl chitosan (effective ingredient content 99%, purchased from Shaanxi Chenming Biotechnology Co., Ltd.) is dissolved in deionized water, 2,3-epoxypropyltrimethylammonium chloride is added, the temperature is raised to 60°C, the reaction is carried out for 24 hours, and the mixture is naturally cooled to room temperature. Then, anhydrous ethanol in an amount equal to the volume of deionized water is added for precipitation. After centrifugation, the precipitate is redissolved in deionized water, and anhydrous ethanol is used for precipitation again. The precipitate is dried to constant weight under vacuum conditions at 60°C to obtain quaternized carboxymethyl chitosan; wherein the mass ratio of the carboxymethyl chitosan to 2,3-epoxypropyltrimethylammonium chloride is 10:1.5, the mass volume ratio of the carboxymethyl chitosan to deionized water is 1 g / mL, the centrifugal speed is 12000 rpm, and the centrifugal time is 5 min; the grafting rate of the quaternized carboxymethyl chitosan is measured to be 9.5% by elemental analysis test; The preparation method of the modified liquid is as follows: polyvinyl alcohol (polymerization degree 1650-1850, model 1788, purchased from Jinan Yuyi Chemical Co., Ltd.) is added to deionized water, heated to 80°C, stirred until dissolved, and then quaternized carboxymethyl chitosan is added, the temperature is lowered to 60°C, stirred for 30 minutes, and then modified nano-silica is added, ultrasonic treatment is performed for 15 minutes, the ultrasonic power is 250W, stirring is continued at 60°C for 30 minutes, and naturally cooled to room temperature. The solution is filtered through a filter to remove undispersed particles to obtain a modified liquid. Example 2

[0018] A method for preparing a cleaning towel made of a degradable material comprises the following steps: Step S1: cellulose pulp, N-methylmorpholine-N-oxide aqueous solution, modifying liquid and fixing agent are uniformly mixed to obtain fiber spinning solution, and then the fiber spinning solution is added into a screw extruder and extruded into raw fibers through a spinneret, and the raw fibers are subjected to coagulation, alcohol washing, water washing, oiling and drying processes to obtain modified lyocell fibers; wherein the mass ratio of the cellulose pulp, N-methylmorpholine-N-oxide aqueous solution, modifying liquid and fixing agent is 10:75:4:0.5, and the mass fraction of the N-methylmorpholine-N-oxide aqueous solution is 55%; the cellulose pulp is hardwood pulp with a degree of polymerization of DP550 and a moisture regain of 7.2%; the fixing agent is triphenylmethane triisocyanate; and the rest is the same as in Example 1; Step S2: spinning the modified lyocell fiber and the cotton fiber by conglomerate spinning to obtain a blended yarn, and then weaving the blended yarn to obtain a cleaning towel; the rest is the same as in Example 1; The modified solution in step S1 comprises the following raw materials in parts by weight: 5 parts of quaternized carboxymethyl chitosan, 0.5 parts of modified nano-silicon dioxide, 4 parts of polyvinyl alcohol, and 80 parts of deionized water; The preparation method of the modified nano-silica is as follows: under stirring conditions, citric acid is dispersed in anhydrous ethanol, 5,6-epoxyhexyltriethoxysilane is added, the temperature is raised to 80°C, the reaction is performed for 6 hours, the reaction is naturally cooled to room temperature, and then nano-silica sol (solid content of 25%, average particle size of 86nm, pH of 8.9) and deionized water are added, the reaction is continued at 70°C for 5 hours after ultrasonic dispersion, the reaction is naturally cooled to room temperature, centrifuged, the precipitate is collected, and the precipitate is centrifuged and washed with anhydrous ethanol and deionized water in turn. The centrifugal speed in the above centrifugal process is 10,000 rpm, and the centrifugal time is 20 minutes. The reaction mixture was centrifuged for 10 minutes, and after centrifugal washing, the mixture was vacuum dried at 60°C to constant weight, and then ground and sieved through an 800-mesh sieve to obtain modified nano-silica; wherein the mass ratio of citric acid, 5,6-epoxyhexyltriethoxysilane, nano-silica sol, and deionized water was 20:20:200:20, the volume ratio of anhydrous ethanol to deionized water was 20:5, the ultrasonic power during ultrasonic dispersion was 150W, and the ultrasonic time was 20 minutes; the grinding process can be carried out using conventional techniques in the art; the grafting rate of the modified nano-silica was measured by thermogravimetric analysis to be 11.8%; The preparation method of the quaternized carboxymethyl chitosan is as follows: under stirring conditions, carboxymethyl chitosan (effective ingredient content 99%, purchased from Shaanxi Chenming Biotechnology Co., Ltd.) is dissolved in deionized water, 2,3-epoxypropyltrimethylammonium chloride is added, the temperature is raised to 70°C, the reaction is carried out for 20 hours, and the mixture is naturally cooled to room temperature. Then, anhydrous ethanol in an amount equal to the volume of deionized water is added for precipitation. After centrifugation, the precipitate is redissolved in deionized water, and anhydrous ethanol is used for precipitation again. The precipitate is dried to constant weight under vacuum conditions at 60°C to obtain quaternized carboxymethyl chitosan; wherein the mass ratio of the carboxymethyl chitosan to 2,3-epoxypropyltrimethylammonium chloride is 10:1, the mass volume ratio of the carboxymethyl chitosan to deionized water is 0.8 g / mL, the centrifugal speed is 12000 rpm, and the centrifugal time is 5 minutes; the grafting rate of the quaternized carboxymethyl chitosan is measured to be 8.9% by elemental analysis test; The preparation method of the modified liquid is as follows: polyvinyl alcohol (polymerization degree 1650-1850, model 1788, purchased from Jinan Yuyi Chemical Co., Ltd.) is added to deionized water, heated to 90°C, stirred until dissolved, and then quaternized carboxymethyl chitosan is added, the temperature is lowered to 70°C, stirred for 20 minutes, and then modified nano-silica is added, ultrasonic treatment is performed for 10 minutes, the ultrasonic power is 250W, stirring is continued at 70°C for 20 minutes, and naturally cooled to room temperature. The solution is filtered through a filter to remove undispersed particles to obtain a modified liquid. Example 3

[0019] A method for preparing a cleaning towel made of a degradable material comprises the following steps: Step S1: uniformly mixing cellulose pulp, N-methylmorpholine-N-oxide aqueous solution, modifying liquid and fixing agent to obtain fiber spinning solution, then adding the fiber spinning solution into a screw extruder and extruding raw fibers through a spinneret, and obtaining modified lyocell fibers after the raw fibers are solidified, washed with alcohol, washed with water, oiled and dried; wherein the mass ratio of the cellulose pulp, N-methylmorpholine-N-oxide aqueous solution, modifying liquid and fixing agent is 15:75:8:0.8, and the mass fraction of the N-methylmorpholine-N-oxide aqueous solution is 53%; the cellulose pulp is hardwood pulp with a degree of polymerization of DP550 and a moisture regain of 7.2%; the fixing agent is triphenylmethane triisocyanate; and the rest is the same as in Example 1; Step S2: spinning the modified lyocell fiber and the cotton fiber by conglomerate spinning to obtain a blended yarn, and then weaving the blended yarn to obtain a cleaning towel; the rest is the same as in Example 1; The modified solution in step S1 comprises the following raw materials in parts by weight: 10 parts of quaternized carboxymethyl chitosan, 1.5 parts of modified nano-silicon dioxide, 8 parts of polyvinyl alcohol, and 120 parts of deionized water; The preparation method of the modified nano-silica is as follows: under stirring conditions, citric acid is dispersed in anhydrous ethanol, 5,6-epoxyhexyltriethoxysilane is added, the temperature is raised to 60°C, the reaction is performed for 8 hours, the reaction is naturally cooled to room temperature, and then nano-silica sol (solid content of 25%, average particle size of 86nm, pH of 8.9) and deionized water are added, the reaction is continued at 50°C for 7 hours after ultrasonic dispersion, the reaction is naturally cooled to room temperature, centrifuged, the precipitate is collected, and the precipitate is centrifuged and washed with anhydrous ethanol and deionized water in turn. The centrifugal speed in the above centrifugal process is 10,000 rpm and the centrifugal time is 20 minutes. The washing process was centrifugal and then vacuum dried at 60°C to constant weight, and then ground and sieved through an 800-mesh sieve to obtain modified nano-silica; wherein the mass ratio of citric acid, 5,6-epoxyhexyltriethoxysilane, nano-silica sol and deionized water was 20:30:250:30, the volume ratio of anhydrous ethanol to deionized water was 20:15, the ultrasonic power during ultrasonic dispersion was 250W, and the ultrasonic time was 10min; the grinding process can be carried out using conventional techniques in the art; the grafting rate of modified nano-silica was measured by thermogravimetric analysis to be 13.1%; The preparation method of the quaternized carboxymethyl chitosan is as follows: under stirring conditions, carboxymethyl chitosan (effective ingredient content 99%, purchased from Shaanxi Chenming Biotechnology Co., Ltd.) is dissolved in deionized water, 2,3-epoxypropyltrimethylammonium chloride is added, the temperature is raised to 50°C, the reaction is carried out for 30 hours, and the mixture is naturally cooled to room temperature. Then, anhydrous ethanol in an amount equal to the volume of deionized water is added for precipitation. After centrifugation, the precipitate is redissolved in deionized water, and anhydrous ethanol is used for precipitation again. The precipitate is dried to constant weight under vacuum conditions at 60°C to obtain quaternized carboxymethyl chitosan; wherein the mass ratio of the carboxymethyl chitosan to 2,3-epoxypropyltrimethylammonium chloride is 10:2, the mass volume ratio of the carboxymethyl chitosan to deionized water is 1.2 g / mL, the centrifugal speed is 12000 rpm, and the centrifugal time is 5 minutes; the grafting rate of the quaternized carboxymethyl chitosan is measured to be 10.2% by elemental analysis test; The preparation method of the modified liquid is as follows: polyvinyl alcohol (polymerization degree 1650-1850, model 1788, purchased from Jinan Yuyi Chemical Co., Ltd.) is added to deionized water, heated to 70°C, stirred until dissolved, and then quaternized carboxymethyl chitosan is added, the temperature is lowered to 50°C, stirred for 40 minutes, and then modified nano-silica is added, ultrasonic treatment is performed for 20 minutes, the ultrasonic power is 250W, stirring is continued at 50°C for 40 minutes, and naturally cooled to room temperature. The solution is filtered through a filter to remove undispersed particles to obtain a modified liquid. Comparative Example 1

[0020] A method for preparing a cleaning towel made of a degradable material is prepared according to the method described in Example 1, except that the modified liquid comprises the following raw materials in parts by weight: 8 parts of carboxymethyl chitosan, 1 part of modified nano-silicon dioxide, 6 parts of polyvinyl alcohol, and 100 parts of deionized water. Comparative Example 2

[0021] A method for preparing a cleaning towel made of a degradable material is prepared according to the method described in Example 1, except that the modified liquid comprises the following raw materials in parts by weight: 8 parts of quaternized carboxymethyl chitosan, 1 part of nano silicon dioxide (commonly available on the market), 6 parts of polyvinyl alcohol, and 100 parts of deionized water. Comparative Example 3

[0022] A method for preparing a cleaning towel made of a degradable material is prepared according to the method described in Example 1, except that the modified liquid comprises the following raw materials in parts by weight: 8 parts of carboxymethyl chitosan, 1 part of nano silicon dioxide (commonly available on the market), 6 parts of polyvinyl alcohol, and 100 parts of deionized water.

[0023] The cleaning towels made of degradable materials prepared in Examples 1-3 and Comparative Examples 1-3 were subjected to relevant performance tests. The water absorption test was conducted in accordance with GB / T 21655.1-2023 "Evaluation of moisture absorption and quick-drying properties of textiles Part 1: Single combination test method"; the wear resistance test was conducted using a TABER wear tester with a load of 500g, a rotation speed of 60r / min, and a wear number of 13,000 times. After the test, the surface of the sample was observed to see if there were holes, fiber breakage, pilling, etc.; the antibacterial performance test was conducted in accordance with GB / T 20944.3-2008 "Evaluation of antibacterial properties of textiles Part 3: Oscillation method"; the breaking strength test was conducted in accordance with GB / T 3923.1-2013 "Tensile properties of textile fabrics Part 1: Determination of breaking strength and breaking elongation"; Biodegradability test: Under natural conditions of 25°C, bury the sample in ordinary soil at a depth of 25 cm. From the beginning of the test, add a small amount of water every 10 days to keep the soil moist. Take it out after 60 days, wash and dry it, and calculate the degradation rate. Degradation rate (%) = (m0-m1) / m0×100%, where m0 is the initial mass of the sample, and m1 is the mass of the sample after 60 days of storage; The above tests were repeated three times and the average value was taken. The test results are shown in Table 1. From the data in Table 1, it can be seen that the cleaning towels prepared in Examples 1-3 not only have good water absorption performance, but also have excellent wear resistance, breaking strength, and antibacterial properties, while maintaining good biodegradability. It can be seen from the data of Example 1 and Comparative Examples 1-3 that quaternary ammonium carboxymethyl chitosan and modified nano-silica are obtained by chemical modification, and cellulose pulp is modified by using quaternary ammonium carboxymethyl chitosan, modified nano-silica, polyvinyl alcohol and other raw materials to further obtain modified lyocell fiber, and finally the modified lyocell fiber is blended with cotton fiber to obtain a cleaning towel. The wear resistance, breaking strength and antibacterial properties of the cleaning towel are significantly improved, and although the biodegradability is slightly reduced, it still maintains a relatively high level.

[0024] Table 1 Test results of relevant properties of cleaning towels made of degradable materials

[0025] Although the embodiments of the present application have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a cleaning towel made of a degradable material, characterized in that: The following steps are involved: Step S1: uniformly mixing cellulose pulp, N-methylmorpholine-N-oxide aqueous solution, modifying solution and fixing agent to obtain fiber spinning solution, and then preparing raw silk from the fiber spinning solution, and the raw silk is coagulated, washed with alcohol, washed with water, oiled and dried to obtain modified lyocell fiber; Step S2: spinning the modified lyocell fiber and the cotton fiber by conglomerate spinning to obtain a blended yarn, and then weaving the blended yarn; The modified solution in step S1 comprises the following raw materials in parts by weight: 5-10 parts of quaternized carboxymethyl chitosan, 0.5-1.5 parts of modified nano-silicon dioxide, 4-8 parts of polyvinyl alcohol, and 80-120 parts of deionized water; The preparation method of the modified nano silicon dioxide is: Under stirring conditions, citric acid is dispersed in anhydrous ethanol, and then 5,6-epoxyhexyltriethoxysilane is added, the temperature is raised to 60-80°C, the reaction is carried out for 6-8 hours, and then cooled to room temperature. Then, nano-silica sol and deionized water are added, and after ultrasonic dispersion, the reaction is continued at 50-70°C for 5-7 hours, cooled to room temperature, and post-treated to obtain modified nano-silica.

2. The method for preparing the cleaning cloth made of degradable material according to claim 1, characterized in that: In the preparation process of the modified nano-silica, the mass ratio of citric acid, 5,6-epoxyhexyltriethoxysilane, nano-silica sol and deionized water is 20:20-30:200-250:20-30.

3. The method for preparing the cleaning cloth made of degradable material according to claim 1, characterized in that: During the preparation of the modified nano-silica, the volume ratio of anhydrous ethanol to deionized water is 20:5-15.

4. The method for preparing the cleaning cloth made of degradable material according to claim 1, characterized in that: During the preparation of the modified nano-silicon dioxide, the ultrasonic power during ultrasonic dispersion is 150-250 W, and the ultrasonic time is 10-20 min.

5. The method for preparing the cleaning cloth made of degradable material according to claim 1, characterized in that: The mass ratio of the cellulose pulp, the N-methylmorpholine-N-oxide aqueous solution, the modifying liquid and the fixing agent in step S1 is 10-15:75:4-8:0.5-0.

8.

6. The method for preparing the cleaning cloth made of degradable material according to claim 1, characterized in that: The preparation method of the modified liquid is as follows: adding polyvinyl alcohol to deionized water, heating to 70-90°C, stirring until dissolved, adding quaternized carboxymethyl chitosan, lowering the temperature to 50-70°C, stirring for 20-40 minutes, then adding modified nano-silica, ultrasonically treating for 10-20 minutes, continuing to stir at 50-70°C for 20-40 minutes, cooling and filtering to obtain the modified liquid.

7. The method for preparing the cleaning cloth made of degradable material according to claim 1, characterized in that: The preparation method of the quaternized carboxymethyl chitosan is as follows: under stirring conditions, carboxymethyl chitosan is dissolved in deionized water, 2,3-epoxypropyltrimethylammonium chloride is added, the temperature is increased to 50-70° C., the reaction is performed for 20-30 hours, the quaternized carboxymethyl chitosan is obtained after cooling to room temperature and post-treatment.

8. The method for preparing the cleaning cloth made of degradable material according to claim 7, characterized in that: The mass ratio of the carboxymethyl chitosan to 2,3-epoxypropyltrimethylammonium chloride is 10:1-2.

9. The method for preparing the cleaning cloth made of degradable material according to claim 7, characterized in that: The mass volume ratio of the carboxymethyl chitosan to deionized water is 0.8-1.2 g / mL.

10. A cleaning towel made of a degradable material prepared by the method according to any one of claims 1 to 9.

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