Antibacterial mask and preparation method thereof

Abstract

The invention relates to the technical field of antibacterial masks, in particular to an antibacterial mask and a preparation method thereof. A preparation method of an antibacterial mask comprises the following steps: uniformly mixing polyethylene terephthalate and modified lotus leaf hydrophobic powder in a weight ratio of (91-95): (5-9), extruding and melting, spinning to obtain fibers, drafting, oiling and winding to obtain fibers, swaying and laying a net, needling and solidifying the fiber net, winding, trimming, and automatically doffing to obtain a non-woven fabric, namely an antibacterial layer; and compounding the antibacterial layer with the surface layer and the inner layer to obtain the antibacterial mask. According to the antibacterial mask provided by the invention, the antibacterial property and the ultraviolet resistance of the antibacterial mask after being washed with water are improved, and the PM2.5 filtering efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of antibacterial mask technology, specifically to an antibacterial mask and its preparation method. Background Technology

[0002] With increasing public health awareness, the market demand for antibacterial masks, as an important personal protective equipment, is growing. Especially in the face of various infectious diseases and air pollution, antibacterial masks can effectively block pathogens and harmful particulate matter, protecting people's respiratory health. However, current antibacterial masks on the market still have many shortcomings in performance, failing to meet people's needs for efficient and long-lasting protection.

[0003] Currently, commonly used antibacterial materials in antibacterial masks mainly include inorganic antibacterial agents (such as zinc oxide and copper oxide), organic antibacterial agents (such as quaternary ammonium salts and phenols), and natural antibacterial agents (such as plant extracts). Among them, inorganic antibacterial agents have received widespread attention due to their advantages such as broad-spectrum antibacterial properties, good thermal stability, and low likelihood of inducing drug resistance. Zinc oxide, as a common inorganic antibacterial agent, has good antibacterial and UV-resistant properties and is widely used in antibacterial textiles and other fields. However, in practical applications, the bonding force between antibacterial agents such as zinc oxide and the mask fiber substrate is often weak, leading to powder shedding during use, which affects the antibacterial durability and overall performance of the mask. In addition to antibacterial properties, UV resistance is also one of the important indicators of antibacterial masks. However, many antibacterial masks currently perform poorly in terms of UV resistance. Although some masks have added materials with UV-resistant functions, the uneven dispersion of the materials or problems with their bonding with the fibers result in unstable UV resistance. Furthermore, the UV protection performance of some masks significantly decreases after washing or prolonged use, rendering them ineffective in blocking harmful UV rays. Therefore, this invention proposes an antibacterial mask and its preparation method. Summary of the Invention

[0004] This invention proposes an antibacterial mask and its preparation method, which improves the antibacterial and UV protection properties of the antibacterial mask after washing and enhances the PM2.5 filtration efficiency.

[0005] The technical solution of the present invention is as follows: In a first aspect, the present invention proposes a method for preparing an antibacterial mask, the steps of which include: mixing polyethylene terephthalate and modified lotus leaf hydrophobic powder in a weight ratio of 91-95:5-9 evenly, extruding and melting the mixture, spinning it to obtain fibers, stretching, oiling, and winding the fibers to obtain a web, laying the fibers into a mesh, then needle-punching and consolidating the mesh, winding, trimming the edges, and automatically unwinding to obtain a nonwoven fabric, which is the antibacterial layer; and combining the antibacterial layer with the outer layer and the inner layer to obtain the antibacterial mask.

[0006] As a further technical solution, the extrusion melting temperature is 250-255℃, the spinning speed is 1400-1450m / min, the drawing speed is 3000-3500m / min; the oiling rate is 0.4%-0.6%; the needle punching depth is 8-12mm, and the needle punching density is 100-200 needles / cm². 2 .

[0007] As a further technical solution, the preparation method of the modified lotus leaf hydrophobic powder includes: mixing a silane coupling agent with an ethanol-water mixed solvent with a volume ratio of 90:10, adjusting the pH value to 4-5 with dilute hydrochloric acid or acetic acid, and stirring at room temperature and 100-200 rpm for 30-40 minutes to obtain a hydrolysate; adding zinc oxide-loaded lotus leaf hydrophobic powder to the above hydrolysate, and mechanically stirring the reaction in a 60℃ water bath for 6-8 hours; after the reaction is completed, filtering, washing, and drying are performed to obtain the final product.

[0008] This invention first involves mixing a silane coupling agent with an ethanol-water mixed solvent to obtain a hydrolysate. This process utilizes the hydrolytic properties of the silane coupling agent, where the silicon-oxygen bonds in the silane coupling agent molecule hydrolyze to generate reactive silanol groups. Subsequently, zinc oxide-loaded lotus leaf hydrophobic powder is added to the hydrolysate. The silanol groups undergo a dehydration condensation reaction with the hydroxyl groups on the surface of the zinc oxide-loaded lotus leaf hydrophobic powder, forming chemical bonds that coat the surface of the zinc oxide-loaded lotus leaf hydrophobic powder with the silane coupling agent. This modification method not only enhances the bonding force between the zinc oxide-loaded lotus leaf hydrophobic powder and polyethylene terephthalate (PET) fibers, preventing powder detachment during use, but also improves the hydrophobic properties of the fibers through the hydrophobic groups of the silane coupling agent, thus enhancing the performance of the antibacterial mask from multiple perspectives.

[0009] As a further technical solution, the weight ratio of the silane coupling agent, the ethanol-water mixed solvent, and the zinc oxide-loaded lotus leaf hydrophobic powder is 4-6:200-300:100.

[0010] As a further technical solution, the silane coupling agent includes silane coupling agent KH-560 and silane coupling agent KH-570 in a weight ratio of 1:3-4.

[0011] In this invention, silane coupling agents KH-560 and KH-570 are used in a weight ratio of 1:3-4. KH-560 and KH-570 have different chemical structures and performance characteristics. KH-560 contains epoxy groups, which can react with hydroxyl groups and other groups on the fiber surface to form strong chemical bonds; KH-570 contains acryloyloxy groups, which, in addition to reacting with the fiber surface, also have a certain polymerization ability, forming a polymer layer on the fiber surface. The combined use of the two produces a synergistic effect: KH-560 provides basic binding force, while KH-570 further enhances the stability and durability of the bond, while improving the hydrophobicity and other physicochemical properties of the fiber surface, thereby comprehensively improving the performance of the antibacterial mask, especially significantly enhancing its durability.

[0012] As a further technical solution, the preparation method of the zinc oxide-loaded lotus leaf hydrophobic powder includes: dispersing 100 parts of refined lotus leaf powder in 200 parts of anhydrous ethanol, and ultrasonically treating for 30-40 min to form a homogeneous suspension; dissolving 6-8 parts of zinc acetate in 100 parts of anhydrous ethanol, adding 2-5 parts of ethanolamine, and stirring at 55-65℃ until completely dissolved to form a zinc amine complex; slowly adding the zinc amine complex solution to the lotus leaf powder suspension, controlling the dropping rate to 1 mL / min; then continuing to add LiOH solution at 350±20 rpm, adjusting the pH value to 10.5±0.2, reacting under microwave-assisted conditions for 2.5-3.5 h, and obtaining the zinc oxide-loaded lotus leaf hydrophobic powder after filtration, washing, and drying.

[0013] In preparing zinc oxide-loaded lotus leaf hydrophobic powder, this invention selects zinc acetate as the zinc source. Compared with other zinc sources such as zinc nitrate and copper sulfate, zinc acetate has unique advantages. When zinc nitrate is used as a zinc source, nitric acid is generated during hydrolysis, affecting the formation of zinc oxide and leading to a decrease in antibacterial and UV-resistant properties. When copper sulfate is used instead of zinc acetate to prepare copper oxide-loaded lotus leaf powder, although copper oxide has antibacterial properties, its efficiency is lower than that of zinc oxide, resulting in inferior overall performance. Zinc acetate, however, can stably provide zinc ions in the reaction system. After forming a zinc amine complex with ethanolamine, it is more conducive to the uniform loading and formation of zinc oxide on the surface of the lotus leaf powder, thus providing superior and longer-lasting antibacterial and UV-resistant properties for antibacterial masks.

[0014] As a further technical solution, the preparation method of the refined lotus leaf powder includes: washing mature, non-rotten lotus leaves, drying them at 55-65℃ to constant weight so that their moisture content is less than 5%, and pulverizing them through an 80-mesh sieve to obtain coarse lotus leaf powder; adding the coarse lotus leaf powder and 4-5 times the weight of anhydrous ethanol into a Soxhlet extractor, refluxing and extracting at 80-90℃ for 4-6 hours, filtering and drying to obtain refined lotus leaf powder.

[0015] As a further technical solution, the LiOH solution is prepared by dissolving 3-8 parts of lithium hydroxide in a mixture of 50 parts of ethanol and water with a volume ratio of 4:1.

[0016] As a further technical solution, the microwave auxiliary conditions are a power of 250-350W, a temperature of 60-70℃, and an intermittent on-time of 25-30s and off-time of 10-15s.

[0017] Secondly, the present invention proposes an antibacterial mask, which is prepared using the method for preparing the antibacterial mask.

[0018] The working principle and beneficial effects of this invention are as follows: In this invention, polyethylene terephthalate (PET) serves as the base fiber material, providing essential mechanical properties and structural support for the antibacterial layer, ensuring the strength and stability of the nonwoven fabric of the mask. The addition of modified lotus leaf hydrophobic powder endows the antibacterial layer with unique antibacterial, UV-resistant, and hydrophobic properties. The two complement each other in performance: the stable structure of PET provides an attachment carrier for the modified lotus leaf hydrophobic powder, allowing its functions to be stably performed; the special functions of the modified lotus leaf hydrophobic powder, in turn, enrich the application performance of PET fibers, achieving a synergistic improvement in material properties, thus preparing an antibacterial layer with multiple excellent properties.

[0019] In this invention, lotus leaf powder serves as a carrier for zinc oxide. Zinc acetate forms a zinc amine complex under the action of ethanolamine, which exhibits good stability and reactivity. This complex is slowly added to a purified lotus leaf powder suspension, where it is uniformly loaded onto the lotus leaf powder surface and reacts to generate zinc oxide. Zinc oxide possesses excellent antibacterial and UV-resistant properties. Its antibacterial mechanism primarily involves generating photogenerated holes and electrons, which react with water and oxygen in the air to produce highly oxidizing hydroxyl radicals and superoxide anion radicals. These active substances can destroy bacterial cell membranes and DNA, thereby achieving a bactericidal effect. Regarding UV protection, zinc oxide can absorb and scatter ultraviolet rays, reducing the harmful effects of ultraviolet radiation on the human body. Lotus leaf powder, as a carrier, provides a large specific surface area for zinc oxide, allowing it to more fully exert its antibacterial and UV-resistant effects. Simultaneously, the loading of zinc oxide also enhances the functionality of the lotus leaf powder. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. 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. In the present invention, polyethylene terephthalate, brand name FR530, was purchased from Shenzhen Hongtai Jinyue Technology Co., Ltd. It should also be noted that the inner layer and outer layer of the mask in the present invention are made of hot-air cotton nonwoven fabric.

[0021] Example 1 This embodiment provides an antibacterial mask, which includes an antibacterial layer. The preparation steps of the antibacterial layer include: mixing polyethylene terephthalate and modified lotus leaf hydrophobic powder in a weight ratio of 93:7 evenly, then extruding and melting the mixture at a temperature of 252°C; spinning the mixture at a speed of 1420 m / min; obtaining the fiber, then drawing, oiling, and winding the fiber at a drawing speed of 3200 m / min; the oiling rate is 0.5%; laying the fiber into a web, and then needle-punching and consolidating the web at a depth of 10 mm and a needle density of 150 needles / cm². 2 The weight of a single-layer cotton web is 20 g / m². 2 The nonwoven fabric, which is the antibacterial layer, is obtained by winding, trimming, and automatic unwinding. The antibacterial mask is obtained by combining the antibacterial layer with the outer and inner layers.

[0022] The preparation method of modified lotus leaf hydrophobic powder includes: Mature, unrotten lotus leaves were washed and dried at 60°C to constant weight, so that the moisture content was 4%. The leaves were then crushed through an 80-mesh sieve to obtain coarse lotus leaf powder. The coarse lotus leaf powder was added to a Soxhlet extractor with 4 times the weight of anhydrous ethanol and refluxed at 85°C for 5 hours. After filtration and drying, refined lotus leaf powder was obtained. 100 parts of refined lotus leaf powder were dispersed in 200 parts of anhydrous ethanol and ultrasonically treated for 35 minutes to form a homogeneous suspension. LiOH solution was obtained by dissolving 5 parts of lithium hydroxide in a mixture of 50 parts of ethanol and water in a volume ratio of 4:1. Seven parts of zinc acetate were dissolved in 100 parts of anhydrous ethanol, and three parts of ethanolamine were added. The mixture was stirred at 60°C until completely dissolved to form a zinc-amine complex. The zinc-amine complex solution was slowly added to the lotus leaf powder suspension, with the dropping rate controlled at 1 mL / min. Then, LiOH solution was added dropwise at 350 rpm to adjust the pH to 10.5. The reaction was carried out for 3 hours under microwave-assisted conditions of 300 W power, 65°C temperature, and intermittent on-off cycle of 30 s and 10 s. The mixture was filtered and the filter cake was washed four times with anhydrous ethanol. The filter cake was then dried in a vacuum drying oven at 80°C for 8 hours to obtain zinc oxide-loaded lotus leaf hydrophobic powder. Five parts of silane coupling agent were mixed with 250 parts of an ethanol-water mixture with a volume ratio of 90:10. The silane coupling agent included silane coupling agent KH-560 and silane coupling agent KH-570 with a weight ratio of 1:3.5. The pH was adjusted to 4.5 with acetic acid, and the mixture was stirred at 150 rpm for 35 minutes at room temperature to obtain a hydrolysate. 100 parts of zinc oxide-loaded lotus leaf hydrophobic powder were added to the hydrolysate, and the mixture was mechanically stirred in a 60°C water bath for 7 hours. After the reaction was completed, the mixture was filtered, and the filter cake was washed three times with anhydrous ethanol. The filter cake was then dried in a vacuum drying oven at 80°C for 6 hours to obtain the final product.

[0023] Example 2 This embodiment provides an antibacterial mask, which includes an antibacterial layer. The preparation steps of the antibacterial layer include: mixing polyethylene terephthalate and modified lotus leaf hydrophobic powder in a weight ratio of 91:9 evenly, then extruding and melting the mixture at a temperature of 250°C; spinning the mixture at a speed of 1400 m / min; obtaining fibers, then drawing, oiling, and winding the fibers at a drawing speed of 3000 m / min; the oiling rate is 0.4%; laying the fibers into a web, and then needle-punching and consolidating the web at a depth of 8 mm and a needle density of 100 needles / cm². 2 The weight of a single-layer cotton web is 20 g / m². 2 The nonwoven fabric, which is the antibacterial layer, is obtained by winding, trimming, and automatic unwinding. The antibacterial mask is obtained by combining the antibacterial layer with the outer and inner layers.

[0024] The preparation method of modified lotus leaf hydrophobic powder includes: Mature, unrotten lotus leaves were washed and dried at 60°C to constant weight, so that the moisture content was 4%. The leaves were then crushed through an 80-mesh sieve to obtain coarse lotus leaf powder. The coarse lotus leaf powder was added to a Soxhlet extractor with 4 times the weight of anhydrous ethanol and refluxed at 85°C for 5 hours. After filtration and drying, refined lotus leaf powder was obtained. 100 parts of refined lotus leaf powder were dispersed in 200 parts of anhydrous ethanol and ultrasonically treated for 30 minutes to form a homogeneous suspension. LiOH solution was obtained by dissolving 3 parts of lithium hydroxide in a mixture of 50 parts of ethanol and water in a volume ratio of 4:1. Six parts of zinc acetate were dissolved in 100 parts of anhydrous ethanol, and two parts of ethanolamine were added. The mixture was stirred at 60°C until completely dissolved to form a zinc-amine complex. The zinc-amine complex solution was slowly added to the lotus leaf powder suspension, with the dropping rate controlled at 1 mL / min. Then, LiOH solution was added dropwise at 350 rpm to adjust the pH to 10.5. The reaction was carried out for 3 hours under microwave-assisted conditions of 300 W power, 65°C temperature, and intermittent on-off-off-10 s cycle. The mixture was filtered and the filter cake was washed three times with anhydrous ethanol. The filter cake was then dried in a vacuum drying oven at 80°C for 8 hours to obtain zinc oxide-loaded lotus leaf hydrophobic powder. Four parts of silane coupling agent were mixed with 200 parts of an ethanol-water mixture with a volume ratio of 90:10. The silane coupling agent included silane coupling agent KH-560 and silane coupling agent KH-570 with a weight ratio of 1:3. The pH was adjusted to 4.5 with acetic acid, and the mixture was stirred at 100 rpm for 30 minutes at room temperature to obtain a hydrolysate. 100 parts of zinc oxide-loaded lotus leaf hydrophobic powder were added to the hydrolysate, and the mixture was mechanically stirred in a 60°C water bath for 6 hours. After the reaction was completed, the mixture was filtered, and the filter cake was washed three times with anhydrous ethanol. The filter cake was then dried in a vacuum drying oven at 80°C for 6 hours to obtain the final product.

[0025] Example 3 This embodiment provides an antibacterial mask, which includes an antibacterial layer. The preparation steps of the antibacterial layer include: mixing polyethylene terephthalate and modified lotus leaf hydrophobic powder in a weight ratio of 95:5 evenly, then extruding and melting the mixture at a temperature of 255°C; spinning the mixture at a speed of 1450 m / min; obtaining fibers, then drawing, oiling, and winding the fibers at a drawing speed of 3500 m / min; the oiling rate is 0.6%; laying the fibers into a web, and then needle-punching and consolidating the web at a depth of 12 mm and a needle density of 200 needles / cm². 2 The weight of a single-layer cotton web is 20 g / m². 2 The nonwoven fabric, which is the antibacterial layer, is obtained by winding, trimming, and automatic unwinding. The antibacterial mask is obtained by combining the antibacterial layer with the outer and inner layers.

[0026] The preparation method of modified lotus leaf hydrophobic powder includes: Mature, unrotten lotus leaves were washed and dried at 60°C to constant weight, so that the moisture content was 4%. The leaves were then crushed through an 80-mesh sieve to obtain coarse lotus leaf powder. The coarse lotus leaf powder was added to a Soxhlet extractor with 4 times the weight of anhydrous ethanol and refluxed at 85°C for 5 hours. After filtration and drying, refined lotus leaf powder was obtained. 100 parts of refined lotus leaf powder were dispersed in 200 parts of anhydrous ethanol and ultrasonically treated for 40 minutes to form a homogeneous suspension. LiOH solution was obtained by dissolving 8 parts of lithium hydroxide in a mixture of 50 parts of ethanol and water in a volume ratio of 4:1. Eight parts of zinc acetate were dissolved in 100 parts of anhydrous ethanol, and five parts of ethanolamine were added. The mixture was stirred at 60°C until completely dissolved to form a zinc-amine complex. The zinc-amine complex solution was slowly added to the lotus leaf powder suspension, with the dropping rate controlled at 1 mL / min. Then, LiOH solution was added dropwise at 350 rpm to adjust the pH to 10.5. The reaction was carried out for 3 hours under microwave-assisted conditions of 300 W power, 65°C temperature, and intermittent on-off-off-10 s cycle. The mixture was filtered and the filter cake was washed five times with anhydrous ethanol. The filter cake was then dried in a vacuum drying oven at 80°C for 8 hours to obtain zinc oxide-loaded lotus leaf hydrophobic powder. Six parts of silane coupling agent were mixed with 300 parts of a mixed solvent of ethanol and water at a volume ratio of 90:10. The silane coupling agent included silane coupling agent KH-560 and silane coupling agent KH-570 at a weight ratio of 1:4. The pH was adjusted to 4.5 with acetic acid, and the mixture was stirred at 200 rpm for 40 minutes at room temperature to obtain a hydrolysate. 100 parts of zinc oxide-loaded lotus leaf hydrophobic powder were added to the above hydrolysate, and the mixture was mechanically stirred in a water bath at 60°C for 8 hours. After the reaction was completed, the mixture was filtered, and the filter cake was washed three times with anhydrous ethanol. The filter cake was then dried in a vacuum drying oven at 80°C for 6 hours to obtain the final product.

[0027] Comparative Example 1 Based on Example 1, adjustments were made. Unlike Example 1, the weight ratio of polyethylene terephthalate to modified lotus leaf hydrophobic powder in Comparative Example 1 was 88:12.

[0028] Comparative Example 2 Based on Example 1, Comparative Example 2 was adjusted in that, unlike Example 1, unmodified refined lotus leaf powder was used in the preparation of the antibacterial layer, that is, it was not modified by loading zinc oxide and silane coupling agent during the preparation process.

[0029] Comparative Example 3 Based on Example 1, adjustments were made. Unlike Example 1, Comparative Example 3 used zinc oxide-loaded lotus leaf hydrophobic powder in the preparation of the antibacterial layer, meaning that it was not modified with silane coupling agent during the preparation process.

[0030] Comparative Example 4 Based on Example 1, adjustments were made. Unlike Example 1, in the preparation of the antibacterial layer in Comparative Example 4, refined lotus leaf powder was used for modification with a silane coupling agent. The steps included: mixing 5 parts of silane coupling agent with 250 parts of an ethanol-water mixed solvent with a volume ratio of 90:10, wherein the silane coupling agent included silane coupling agent KH-560 and silane coupling agent KH-570 with a weight ratio of 1:3.5; adjusting the pH value to 4.5 with acetic acid, and stirring at 150 rpm for 35 minutes at room temperature to obtain a hydrolysate; adding 100 parts of refined lotus leaf powder to the above hydrolysate, and mechanically stirring the reaction in a 60°C water bath for 7 hours; after the reaction was completed, filtration was performed, the filter cake was washed 3 times with anhydrous ethanol, and the filter cake was dried in a vacuum drying oven at 80°C for 6 hours to obtain the final product.

[0031] Comparative Example 5 Based on Example 1, the following adjustment was made: In Comparative Example 5, zinc acetate was replaced with an equimolar amount of zinc nitrate during the preparation of the modified lotus leaf hydrophobic powder.

[0032] Comparative Example 6 Based on Example 1, adjustments were made. Unlike Example 1, in Comparative Example 6, zinc acetate was replaced with an equimolar amount of copper sulfate during the preparation of modified lotus leaf hydrophobic powder to prepare copper oxide-loaded lotus leaf powder.

[0033] Comparative Example 7 Based on Example 1, adjustments were made. Unlike Example 1, in Comparative Example 7, the silane coupling agent was only silane coupling agent KH-560.

[0034] Comparative Example 8 Based on Example 1, adjustments were made. Unlike Example 1, in Comparative Example 8, the silane coupling agent was only silane coupling agent KH-570.

[0035] Test example: The antibacterial layers of the antibacterial masks prepared in Examples 1-3 and Comparative Examples 1-8 were tested as follows: Preparation of test bacterial suspension: Using Staphylococcus aureus (representing Gram-positive bacteria) and Escherichia coli (representing Gram-negative bacteria) as test bacteria, prepare a solution with a concentration of 4 × 10⁻⁶ according to the usage instructions. 5 Prepare bacterial suspension at CFU / mL; Antibacterial rate: determined according to GB / T20944.3-2008 "Evaluation of antibacterial properties of textiles - Part 3: Shaking method", with Escherichia coli as the bacterial strain. UV protection performance: is expressed by UPF and is determined in accordance with GB / T18830-2009 "Evaluation of UV protection performance of textiles"; PM2.5 filtration efficiency: The testing instrument used was a portable American TSI8530 DustPM2.5 direct meter to measure the PM2.5 concentration in indoor air after the antibacterial layer treatment. The PM2.5 concentration in the indoor air before the test was 36.4 μg / m³. 3 Among them, PM2.5 removal rate (%) = (36.4 μg / m³) 3 -PM2.5 concentration in treated indoor air) / PM2.5 concentration in indoor air × 100%.

[0036] The test results are shown in Table 1 below: Table 1

[0037] Based on the above, Examples 1-3 all exhibit excellent antibacterial properties (original antibacterial rate >99.5%, >98% after 100 washes), good UV resistance (UPF≥50), and high PM2.5 filtration efficiency (>98%). This indicates that using a 93:7 to 95:5 ratio of polyester chips to modified lotus leaf hydrophobic powder, combined with a modification process using loaded zinc oxide and silane coupling agents, can achieve long-lasting antibacterial, UV resistance, and filtration performance.

[0038] Comparative Example 1: The ratio of polyethylene terephthalate to modified lotus leaf hydrophobic powder was 88:12. The excessively high proportion of modified lotus leaf hydrophobic powder resulted in a loose fiber structure and easy powder shedding. Initially, the antibacterial rate was high, but it significantly decreased after washing, and the UV resistance and PM2.5 filtration efficiency were also low. This indicates that an excessively high powder ratio impairs the integrity and durability of the fiber.

[0039] Comparative Example 2 used unmodified refined lotus leaf powder, without zinc oxide and silane coupling agent modification. The lotus leaf powder itself has weak antibacterial properties and poor binding. It exhibited extremely low antibacterial rate, poor UV protection, and decreased PM2.5 filtration efficiency. This demonstrates that unmodified lotus leaf powder cannot provide effective and long-lasting antibacterial and UV protection functions.

[0040] Comparative Example 3 used hydrophobic lotus leaf powder loaded with zinc oxide but without modification by a silane coupling agent. While the zinc oxide provided good initial antibacterial and UV resistance, the lack of a silane coupling agent resulted in severe powder detachment after washing, leading to a sharp drop in antibacterial rate and a decrease in UV resistance. This indicates that silane coupling agents are crucial for improving durability.

[0041] Comparative Example 4 used refined lotus leaf powder modified with a silane coupling agent but without zinc oxide loading. The silane coupling agent improved the bonding between the powder and the fiber, but the lotus leaf powder itself had insufficient antibacterial properties, a low antibacterial rate, and only average UV resistance and PM2.5 filtration efficiency. This demonstrates that loading zinc oxide is key to enhancing antibacterial and UV resistance properties.

[0042] Comparative Example 5 used zinc nitrate instead of zinc acetate. Zinc nitrate, as the zinc source, resulted in slightly lower antibacterial performance and slightly weaker UV resistance compared to Example 1 due to the nitric acid produced during hydrolysis affecting zinc oxide formation. However, the overall performance was still good, indicating that zinc acetate was a better choice.

[0043] Comparative Example 6 used copper sulfate instead of zinc acetate to prepare copper oxide-loaded lotus leaf powder. Copper oxide has antibacterial properties, but its efficiency is not as good as zinc oxide, with a lower antibacterial rate, and its UV resistance and PM2.5 filtration efficiency are also slightly inferior. This indicates that zinc oxide is superior to copper oxide in overall performance.

[0044] Comparative Example 7 used only the silane coupling agent KH-560. KH-560 alone provided good binding force, and its antibacterial and UV resistance properties were close to those of Example 1, but slightly lower than those of the mixed coupling agents. This indicates that the combined use of KH-560 and KH-570 has a synergistic effect and can further improve durability.

[0045] Comparative Example 8 used only the silane coupling agent KH-570. Similar to Comparative Example 7, KH-570 alone performed well, but its UV resistance was slightly lower. This confirms that mixed coupling agents are more effective in optimizing hydrophobicity and binding force.

[0046] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. 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 an antibacterial mask, characterized in that the steps include... include: After uniformly mixing polyethylene terephthalate and modified lotus leaf hydrophobic powder in a weight ratio of 91-95:5-9, the mixture is extruded and melted, then spun to obtain fibers. The fibers are then stretched, oiled, and wound to obtain a web. The web is then needle-punched and consolidated, wound, trimmed, and automatically unwound to obtain a nonwoven fabric, which is the antibacterial layer. The antibacterial layer is then combined with the outer and inner layers to obtain the antibacterial mask.

2. The method for preparing an antibacterial mask according to claim 1, characterized in that, The extrusion melting temperature is 250-255℃, the spinning speed is 1400-1450 m / min, the drawing speed is 3000-3500 m / min, the oiling rate is 0.4%-0.6%, the needle punching depth is 8-12 mm, and the needle punching density is 100-200 needles / cm². 2 .

3. The method for preparing an antibacterial mask according to claim 1, characterized in that, The preparation method of the modified lotus leaf hydrophobic powder includes: mixing a silane coupling agent with an ethanol-water mixed solvent with a volume ratio of 90:10, adjusting the pH value to 4-5 with dilute hydrochloric acid or acetic acid, and stirring at room temperature and 100-200 rpm for 30-40 minutes to obtain a hydrolysate; adding zinc oxide-loaded lotus leaf hydrophobic powder to the above hydrolysate, and mechanically stirring the reaction in a 60℃ water bath for 6-8 hours; after the reaction is completed, filtering, washing, and drying are performed to obtain the final product.

4. The method for preparing an antibacterial mask according to claim 3, characterized in that, The weight ratio of the silane coupling agent, the ethanol-water mixed solvent, and the zinc oxide-loaded lotus leaf hydrophobic powder is 4-6:200-300:

100.

5. The method for preparing an antibacterial mask according to claim 3, characterized in that, The silane coupling agent comprises silane coupling agent KH-560 and silane coupling agent KH-570 in a weight ratio of 1:3-4.

6. The method for preparing an antibacterial mask according to claim 3, characterized in that, The preparation method of the zinc oxide-loaded lotus leaf hydrophobic powder includes: dispersing 100 parts of refined lotus leaf powder in 200 parts of anhydrous ethanol, and ultrasonically treating for 30-40 min to form a homogeneous suspension; dissolving 6-8 parts of zinc acetate in 100 parts of anhydrous ethanol, adding 2-5 parts of ethanolamine, and stirring at 55-65℃ until completely dissolved to form a zinc amine complex; slowly adding the zinc amine complex solution to the lotus leaf powder suspension, controlling the dropping rate to 1 mL / min; then continuing to add LiOH solution at 350±20 rpm, adjusting the pH to 10.5±0.2, reacting under microwave-assisted conditions for 2.5-3.5 h, and obtaining the zinc oxide-loaded lotus leaf hydrophobic powder after filtration, washing, and drying.

7. The method for preparing an antibacterial mask according to claim 6, characterized in that, The method for preparing the refined lotus leaf powder includes: washing mature, non-rotten lotus leaves, drying them at 55-65℃ to constant weight so that their moisture content is less than 5%, and pulverizing them through an 80-mesh sieve to obtain coarse lotus leaf powder; adding the coarse lotus leaf powder and 4-5 parts by weight of anhydrous ethanol into a Soxhlet extractor, refluxing and extracting at 80-90℃ for 4-6 hours, filtering and drying to obtain refined lotus leaf powder.

8. The method for preparing an antibacterial mask according to claim 6, characterized in that, The LiOH solution is prepared by dissolving 3-8 parts of lithium hydroxide in a mixture of 50 parts of ethanol and water with a volume ratio of 4:

1.

9. The method for preparing an antibacterial mask according to claim 6, characterized in that, The microwave-assisted conditions are a power of 250-350W, a temperature of 60-70℃, and an intermittent on-off cycle of 25-30s and 10-15s.

10. An antibacterial mask, characterized in that, The antibacterial mask is prepared using the preparation method described in any one of claims 1-9.

Images