Preparation method of breathable high-elasticity mask fabric

Abstract

This invention discloses a method for preparing a breathable and highly elastic mask fabric, relating to the field of textile fabric materials technology. The breathable and highly elastic mask fabric prepared by this invention includes an upper layer, a middle layer, and a lower layer; the upper and lower layers are both nonwoven fabrics, and the middle layer is a composite membrane; the nonwoven fabric is obtained by melt-blowing polybutylene terephthalate composite masterbatch; the composite membrane is obtained by electrospinning a composite of hydroxyl polylactic acid and 4-guanidine phthalate; modified graphene oxide is introduced onto the end groups of polybutylene terephthalate to enhance the elasticity and heat resistance of the nonwoven fabric; the introduction of 4-guanidine phthalate onto the hydroxyl polylactic acid gives the composite membrane antibacterial properties while enhancing filtration, breathability, and stain resistance.

Description

Technical Field

[0001] This invention relates to the field of textile fabric materials technology, specifically to a method for preparing a breathable and highly elastic mask fabric. Background Technology

[0002] In the prevention of infectious diseases, masks are used to protect against viruses and bacteria transmitted through droplets, serving as a convenient protective measure to safeguard humans from pathogens. People wear masks to create a "filter barrier" for the respiratory tract, filtering inhaled air and preventing dust, bacteria, viruses, and various harmful gases from entering the body. However, some viruses and bacteria are stubborn and cunning, and the filtration properties of ordinary mask fabric alone are insufficient to isolate them. Therefore, developing antibacterial and antiviral masks is crucial for better protecting human health.

[0003] However, when using protective clothing in summer, the temperature inside the protective clothing is high, which not only makes it easy for bacteria to grow, but also affects the performance of the mask. If the mask needs to be replaced, the protective clothing will inevitably need to be replaced, resulting in excessive use of resources. While pursuing antibacterial properties, it is also necessary to ensure the heat resistance, breathability, and stain resistance of the mask. Therefore, this invention has researched and prepared a mask fabric that is highly elastic, heat-resistant, and has good filtration, breathability, and stain resistance. Summary of the Invention

[0004] The purpose of this invention is to provide a breathable and highly elastic mask fabric and its preparation method to solve the problems mentioned in the background art.

[0005] A breathable and highly elastic mask fabric includes an upper layer, a middle layer, and a lower layer, wherein the upper and lower layers are non-woven fabrics and the middle layer is a composite film.

[0006] Preferably, the nonwoven fabric is obtained by melt-blowing polybutylene terephthalate composite masterbatch; the polybutylene terephthalate composite masterbatch is obtained by introducing modified graphene oxide onto the end groups of polybutylene terephthalate; the modified graphene oxide is obtained by reacting amino graphene oxide with calcium pyridine-2,3-dicarboxylate.

[0007] Preferably, the composite membrane is prepared by electrospinning a composite of hydroxyl polylactic acid and 4-guanidine phthalate.

[0008] Preferably, the hydroxyl polylactic acid is prepared by reacting ethanolamine with polylactic acid; the 4-guanidinophthalic acid salt is prepared by reacting thiourea trioxide with 4-aminophthalic acid.

[0009] Preferably, the method for preparing the breathable and highly elastic mask fabric includes the following specific steps:

[0010] (1) Pyridine-2,3-dicarboxylic acid and anhydrous ethanol are mixed in a mass ratio of 3:15 to 3:20, and the pH is adjusted to 6 to 7 with ammonia. A calcium nitrate ethanol solution with a mass fraction of 3 to 8% is added dropwise at a rate of 5 to 8 ml / min. The molar ratio of pyridine-2,3-dicarboxylic acid to calcium nitrate is 3:2 to 3:2.2. The pH is adjusted to 6 to 7 with ammonia. Then, 3 to 5 times the mass of pyridine-2,3-dicarboxylic acid is added, and the mixture is stirred at 50 to 80 rpm for 24 to 36 h. After the reaction, the mixture is allowed to stand for 5 to 8 h, filtered, and washed 3 to 5 times with anhydrous ethanol, and then washed 3 to 5 times with acetone. The mixture is then transferred to a drying oven at 50 to 60 °C and dried to constant weight to obtain modified graphene oxide.

[0011] (2) After mixing polybutylene terephthalate, modified graphene oxide and tannic acid in a mass ratio of 40:8:3~50:15:7, place them in a high-speed mixer and stir at 90~120℃ and 600~1000rpm for 10~20min. Then transfer them to a drawing machine and draw them through the spinneret to form a long fiber web. The long fiber web is hot-pressed by a hot press and cooled to set to obtain a non-woven fabric. Cut it into the same size to form the upper and lower layers.

[0012] (3) Mix deionized water, potassium carbonate and 4-aminophthalic acid in a mass ratio of 7:1:1.5~8:1.5:3 and stir until dissolved. Add 0.8~0.9 times the mass of 4-aminophthalic acid in 5~8 portions of thiourea trioxide at intervals of 10~15 min. After addition, react at room temperature for 4~6 h, let stand for 24 h, filter and wash with acetone 3~5 times, then disperse in 8~10 times the mass of 4-aminophthalic acid in deionized water, heat to 80~90℃, stir until dissolved, add 0.4~0.5 times the mass of 4-aminophthalic acid in hydrochloric acid solution with a mass fraction of 36~38%, react for 0.5~1 h, filter while hot, let stand for 10~12 h, then cool to 4~5℃, filter, and vacuum dry at 80~90℃ to obtain 4-guanidinophthalic acid salt.

[0013] (4) Mix dichloromethane, dimethylformamide, hydroxy polylactic acid and 4-guanidinophthalate salt in a mass ratio of 8:2:1.5:0.5~8:2:3:1.5 and stir at 30~50 rpm for 1~3 h to obtain an electrospinning solution. Perform electrospinning to obtain a composite membrane.

[0014] (5) Lay the lower layer, composite film and upper layer in sequence, scrape the edges, press on a hot press at 90~120℃ for 3~5 minutes, cool to room temperature, soak in acetone solution with a mass fraction of 90~95% for 4~6 minutes, take it out and air dry naturally to obtain breathable and elastic mask fabric.

[0015] Preferably, in step (1) above: the preparation method of amino graphene oxide is as follows: silane coupling agent KH560, triethylenetetramine and anhydrous ethanol are mixed in a mass ratio of 1:2:15~1:2.5:20 and reacted at room temperature for 20~24h to obtain solution A; graphene oxide and deionized water are mixed in a mass ratio of 1:15~1:20 and sonicated at 40~50kHz for 0.5~1h to obtain solution B; solution A and solution B are mixed in a mass ratio of 4:1~5:1, the pH is adjusted to 5~5.5 with acetic acid, the temperature is raised to 80~90℃ and reacted for 20~24h, after the reaction is completed, the mixture is filtered and washed 5~8 times with anhydrous ethanol and deionized water, and finally dried in a vacuum drying oven at 50~60℃ to constant weight to obtain amino graphene oxide.

[0016] Preferably, in step (2) above, the nonwoven fabric basis weight is 30~50 g / m². 2 .

[0017] Preferably, in step (3) above: the preparation method of thiourea trioxide is as follows: under ice bath conditions, thiourea dioxide is mixed with a peracetic acid solution with a mass fraction of 1~3%, reacted for 3~3.5h, filtered and washed 3~5 times with anhydrous ethanol, and dried to constant weight in a vacuum drying oven at 50~60℃ to obtain thiourea trioxide.

[0018] Preferably, in step (4) above, the preparation method of hydroxy polylactic acid is as follows: polylactic acid is dispersed in 1,4-dioxane at 12 to 15 times the mass of polylactic acid, heated to 50 to 60°C, sonicated at 40 to 50 kHz for 10 to 30 min, and ethanolamine solution with a mass fraction of 1 to 3% at a rate of 5 to 8 ml / min is added dropwise at 1.3 to 1.5 times the mass of polylactic acid. The reaction is continued for 20 to 30 min, and the mixture is transferred to a freezer at -40 to -45°C and frozen for 10 to 12 h. Then it is placed in a freezer at -4 to -5°C for extraction for 4 to 5 days, with the water changed three times a day during extraction. Finally, it is placed in a freeze dryer at -50 to -60°C for freeze drying to obtain hydroxy polylactic acid.

[0019] Preferably, in step (4) above: during electrospinning, the receiving distance is 15~18cm, the injection speed of the spinning solution is 1~3mL / h, the relative humidity is 45~55%, the temperature is 23~27℃, and the voltage between the electrodes is 15~18kV.

[0020] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0021] The present invention provides a breathable and highly elastic mask fabric comprising an upper layer, a middle layer, and a lower layer; the upper and lower layers are both non-woven fabrics, and the middle layer is a composite film; the non-woven fabric is obtained by melt-blowing polybutylene terephthalate composite masterbatch; the composite film is obtained by electrospinning a composite of hydroxyl polylactic acid and 4-guanidine phthalate salt.

[0022] Polybutylene terephthalate (PBPT) composite masterbatch is prepared by introducing modified graphene oxide onto the end groups of PBPT. The modified graphene oxide is obtained by reacting amino graphene oxide with calcium pyridine-2,3-dicarboxylate. The interaction between calcium ions and amino graphene oxide sheets enhances the mechanical strength and elastic modulus of the modified graphene oxide, improving the elasticity of the nonwoven fabric. Pyridine is introduced onto the surface of amino graphene oxide to enhance hydrophilicity. The modified graphene oxide is then reacted with the end carboxyl groups on PBPT to introduce the modified graphene oxide into the long chain, enhancing the elastic modulus of the nonwoven fabric. At the same time, tannic acid is used to crosslink the modified graphene oxide onto PBPT to improve crystallinity and heat resistance of the nonwoven fabric.

[0023] Hydroxylated polylactic acid (PLA) is prepared by reacting ethanolamine with PLA; 4-guanidinophthalate is prepared by reacting thiourea trioxide with 4-aminophthalic acid. Ethanolamine introduces hydroxyl groups into PLA, and after electrospinning, the 4-guanidinophthalate is combined with it. The hydroxyl groups react with benzoic acid, and the introduction of guanidino groups enhances antibacterial properties while also reducing the spacing of the porous microfibers produced by electrospinning, thus enhancing filtration performance. When the upper and lower layers are laminated with the middle layer composite membrane, acetone is used for swelling treatment, which increases and deepens the pores on the porous microfibers in the middle layer, enhancing breathability. After swelling, the porous microfibers cause the upper and lower nonwoven fabrics to form nano-protrusions, allowing the hydrophilic upper and lower layers to form a hydration layer, giving the mask fabric anti-fouling properties. Detailed Implementation

[0024] 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.

[0025] To more clearly illustrate the method provided by the present invention, the following embodiments are provided for detailed explanation. The test methods for various indicators of the breathable and highly elastic mask fabric prepared in the embodiments and comparative examples are as follows:

[0026] Elasticity: The breathable and highly elastic mask fabrics prepared in the examples and comparative examples were subjected to a breaking elongation test.

[0027] Heat resistance: The breathable and highly elastic mask fabrics prepared in the examples and comparative examples were subjected to limiting oxygen index tests.

[0028] Antibacterial properties: The breathable and highly elastic mask fabrics prepared in the examples and comparative examples were tested for antibacterial properties in accordance with GB / T20944.

[0029] Breathability: The breathable and highly elastic mask fabrics prepared in the examples and comparative examples were tested for breathability in accordance with GB / T5453.

[0030] Stain resistance: The breathable and highly elastic mask fabrics prepared in the examples and comparative examples were subjected to water contact angle tests using a surface contact angle tester.

[0031] Example 1

[0032] (1) Silane coupling agent KH560, triethylenetetramine, and anhydrous ethanol were mixed at a mass ratio of 1:2:15 and reacted at room temperature for 20 h to obtain solution A; graphene oxide and deionized water were mixed at a mass ratio of 1:15 and sonicated at 40 kHz for 0.5 h to obtain solution B; solution A and solution B were mixed at a mass ratio of 4:1, the pH was adjusted to 5 with acetic acid, and the temperature was raised to 80 ℃ for 20 h. After the reaction was completed, the mixture was filtered and washed 5 times with anhydrous ethanol and deionized water. Finally, it was dried in a vacuum drying oven at 50 ℃ to constant weight to obtain amino-based graphene oxide; pyridine-2, 3-Dicarboxylic acid and anhydrous ethanol were mixed at a mass ratio of 3:15, and the pH was adjusted to 6 with ammonia. A 3% calcium nitrate ethanol solution was added dropwise at a rate of 5 ml / min. The molar ratio of pyridine-2,3-dicarboxylic acid to calcium nitrate was 3:2. The pH was adjusted to 6 with ammonia. Then, amino-based graphene oxide with a mass of 3 times that of pyridine-2,3-dicarboxylic acid was added, and the mixture was stirred at 50 rpm for 24 h. After the reaction, the mixture was allowed to stand for 5 h, filtered, and washed three times with anhydrous ethanol and then three times with acetone. The mixture was then transferred to a drying oven at 50 °C and dried to constant weight to obtain modified graphene oxide.

[0033] (2) Polybutylene terephthalate, modified graphene oxide, and tannic acid were mixed in a mass ratio of 40:8:3 and placed in a high-speed mixer. The mixture was stirred at 90°C and 600 rpm for 10 minutes. The mixture was then transferred to a fiber drawing machine and drawn through a spinneret to form a long fiber web. The long fiber web was then hot-pressed into shape using a hot press. After cooling and setting, a weight of 30 g / m² was obtained. 2 The non-woven fabric is cut into the same size, which constitutes the upper and lower layers;

[0034] (3) Under ice bath conditions, thiourea dioxide was mixed with a 1% peracetic acid solution and reacted for 3 hours. After filtration, it was washed three times with anhydrous ethanol and dried in a vacuum drying oven at 50°C to constant weight to obtain thiourea trioxide. Deionized water, potassium carbonate and 4-aminophthalic acid were mixed and stirred until dissolved in a mass ratio of 7:1:1.5. Thiourea trioxide with a mass of 0.8 times that of 4-aminophthalic acid was added in 5 portions with an interval of 10 minutes. After the addition was completed, the mixture was reacted at room temperature for 4 hours and allowed to stand for 24 hours. After filtration, it was washed three times with acetone and then dispersed in deionized water with a mass of 8 times that of 4-aminophthalic acid. The mixture was heated to 80°C and stirred until dissolved. Hydrochloric acid solution with a mass of 36% was added with a mass of 0.4 times that of 4-aminophthalic acid. After reacting for 0.5 hours, it was filtered while hot and allowed to stand for 10 hours. Then it was cooled to 4°C, filtered, and dried under vacuum at 80°C to obtain 4-guanidinophthalate salt.

[0035] (4) Disperse polylactic acid in 1,4-dioxane at 12 times the mass of polylactic acid, heat to 50°C, sonicate at 40 kHz for 10 min, add 1.3 times the mass of polylactic acid in 1% ethanolamine solution at a rate of 5 ml / min, continue the reaction for 20 min, transfer to a freezer at -40°C and freeze for 10 h, then place in a freezer at -4°C for extraction for 4 days, changing the water three times a day during extraction, and finally place in a freeze dryer at -50°C for cooling. Hydroxylactic acid was prepared by freeze drying; dichloromethane, dimethylformamide, hydroxyl polylactic acid and 4-guanidinophthalate were mixed in a mass ratio of 8:2:1.5:0.5 and stirred at 30 rpm for 1 h to prepare an electrospinning solution. Electrospinning was carried out with a receiving distance of 15-18 cm, a feeding speed of 1 mL / h, a relative humidity of 45%, a temperature of 23 °C and a voltage of 15 kV to prepare a composite membrane.

[0036] (5) Lay the lower layer, composite film and upper layer in sequence, scrape the edges, press for 3 minutes on a hot press at 90°C, cool to room temperature, soak in 90% acetone solution for 4 minutes, take out and air dry naturally to obtain breathable and elastic mask fabric.

[0037] Example 2

[0038] (1) Silane coupling agent KH560, triethylenetetramine, and anhydrous ethanol were mixed at a mass ratio of 1:2.2:18 and reacted at room temperature for 22 h to obtain solution A; graphene oxide and deionized water were mixed at a mass ratio of 1:18 and sonicated at 45 kHz for 0.5 h to obtain solution B; solution A and solution B were mixed at a mass ratio of 4.5:1, the pH was adjusted to 5 with acetic acid, and the temperature was raised to 85 ℃ for 22 h. After the reaction was completed, the mixture was filtered and washed 6 times with anhydrous ethanol and deionized water. Finally, it was dried in a vacuum drying oven at 55 ℃ to constant weight to obtain amino-based graphene oxide; pyridine-2,3 1. A mixture of pyridine-2,3-dicarboxylic acid and anhydrous ethanol at a mass ratio of 3:18 was prepared, and the pH was adjusted to 6.5 with ammonia. A 5% calcium nitrate ethanol solution was added dropwise at a rate of 6 ml / min. The molar ratio of pyridine-2,3-dicarboxylic acid to calcium nitrate was 3:2.1. The pH was adjusted to 6.5 with ammonia. Then, 4 times the mass of amino-2,3-dicarboxylic acid graphene oxide was added, and the mixture was stirred at 60 rpm for 30 h. After the reaction, the mixture was allowed to stand for 6 h, filtered, and washed 4 times with anhydrous ethanol, then washed twice with acetone. The mixture was then transferred to a drying oven at 55 °C and dried to constant weight to obtain modified graphene oxide.

[0039] (2) Polybutylene terephthalate, modified graphene oxide, and tannic acid were mixed in a mass ratio of 45:10:5 and placed in a high-speed mixer. The mixture was stirred at 105°C and 800 rpm for 15 minutes. The mixture was then transferred to a fiber drawing machine and drawn through a spinneret to form a long fiber web. The long fiber web was then hot-pressed into shape using a hot press. After cooling and setting, a weight of 40 g / m² was obtained. 2 The non-woven fabric is cut into the same size, which constitutes the upper and lower layers;

[0040] (3) Under ice bath conditions, thiourea dioxide was mixed with a 2% peracetic acid solution and reacted for 3-3.5 h. After filtration and washing four times with anhydrous ethanol, the mixture was dried to constant weight in a vacuum drying oven at 55 °C to obtain thiourea trioxide. Deionized water, potassium carbonate, and 4-aminophthalic acid were mixed and stirred until dissolved in a mass ratio of 7.5:1.2:2. Thiourea trioxide was added in 6 portions at 13-fold intervals, with a mass ratio of 0.85 times that of 4-aminophthalic acid. After the addition was completed, the reaction was carried out at room temperature for 5 hours, then allowed to stand for 24 hours. The mixture was filtered and washed four times with acetone. It was then dispersed in deionized water at a mass of 9 times that of 4-aminophthalic acid, heated to 85°C, stirred until dissolved, and 0.45 times the mass of 37% hydrochloric acid solution of 4-aminophthalic acid was added. The mixture was reacted for 0.5 hours, filtered while hot, allowed to stand for 11 hours, cooled to 4°C, filtered, and dried under vacuum at 85°C to obtain 4-guanidinophthalate salt.

[0041] (4) Disperse polylactic acid in 1,4-dioxane at 13 times the mass of polylactic acid, heat to 55℃, sonicate at 45kHz for 20min, add ethanolamine solution at 1.4 times the mass of polylactic acid with a mass fraction of 2% at a rate of 6ml / min, continue the reaction for 25min, transfer to a freezer at -43℃ and freeze for 11h, then place in a freezer at -4℃ for extraction for 4d, change the water three times a day during extraction, and finally freeze dry in a freeze dryer at -55℃ to obtain hydroxyl polylactic acid; mix dichloromethane, dimethylformamide, hydroxyl polylactic acid and 4-guanidinophthalate salt at a mass ratio of 8:2:2:1, stir at 40rpm for 2h to obtain electrospinning solution, perform electrospinning, the receiving distance is 16cm, the injection speed of the spinning solution is 2mL / h, the relative humidity is 50%, the temperature is 25℃, and the polar voltage is 16kV to obtain composite membrane;

[0042] (5) Lay the lower layer, composite film and upper layer in sequence, scrape the edges, press for 4 minutes on a hot press at 105℃, cool to room temperature, soak in 93% acetone solution for 5 minutes, take out and air dry naturally to obtain breathable and elastic mask fabric.

[0043] Example 3

[0044] (1) Silane coupling agent KH560, triethylenetetramine, and anhydrous ethanol were mixed at a mass ratio of 1:2.5:20 and reacted at room temperature for 24 h to obtain solution A; graphene oxide and deionized water were mixed at a mass ratio of 1:20 and sonicated at 50 kHz for 1 h to obtain solution B; solution A and solution B were mixed at a mass ratio of 5:1, the pH was adjusted to 5.5 with acetic acid, and the temperature was raised to 90 ℃ for 24 h. After the reaction was completed, the mixture was filtered and washed 8 times with anhydrous ethanol and deionized water. Finally, it was dried in a vacuum drying oven at 60 ℃ to constant weight to obtain amino-based graphene oxide; pyridine-2, 3-Dicarboxylic acid and anhydrous ethanol were mixed at a mass ratio of 3:20, and the pH was adjusted to 7 with ammonia. An 8% calcium nitrate ethanol solution was added dropwise at a rate of 8 ml / min. The molar ratio of pyridine-2,3-dicarboxylic acid to calcium nitrate was 3:2.2. The pH was adjusted to 7 with ammonia. Five times the mass of pyridine-2,3-dicarboxylic acid amino-graphene oxide was added, and the mixture was stirred at 80 rpm for 36 h. After the reaction, the mixture was allowed to stand for 8 h, filtered, and washed 5 times with anhydrous ethanol, then washed 5 times with acetone. The mixture was then transferred to a drying oven at 60 °C and dried to constant weight to obtain modified graphene oxide.

[0045] (2) Polybutylene terephthalate, modified graphene oxide, and tannic acid were mixed in a mass ratio of 50:15:7 and placed in a high-speed mixer. The mixture was stirred at 120°C and 1000 rpm for 20 minutes. The mixture was then transferred to a fiber drawing machine and drawn through a spinneret to form a long fiber web. The long fiber web was then hot-pressed into shape using a hot press. After cooling and setting, a weight of 50 g / m² was obtained. 2 The non-woven fabric is cut into the same size, which constitutes the upper and lower layers;

[0046] (3) Under ice bath conditions, thiourea dioxide was mixed with a 3% peracetic acid solution and reacted for 3.5 h. After filtration and washing five times with anhydrous ethanol, the mixture was dried to constant weight in a vacuum drying oven at 60 °C to obtain thiourea trioxide. Deionized water, potassium carbonate and 4-aminophthalic acid were mixed and stirred until dissolved in a mass ratio of 8:1.5:3. Thiourea trioxide was added in 8 portions, with an interval of 15 min between each portion. After the addition was completed, the reaction was carried out at room temperature for 6 hours, allowed to stand for 24 hours, filtered and washed 5 times with acetone, and then dispersed in deionized water at 8 to 10 times the mass of 4-aminophthalic acid. The mixture was heated to 90°C and stirred until dissolved. 0.5 times the mass of 4-aminophthalic acid and 38% hydrochloric acid solution were added. After reacting for 1 hour, the mixture was filtered while hot and allowed to stand for 12 hours. The mixture was then cooled to 5°C, filtered, and dried under vacuum at 90°C to obtain 4-guanidinophthalic acid salt.

[0047] (4) Disperse polylactic acid in 1,4-dioxane at 15 times the mass of polylactic acid, heat to 60°C, sonicate at 50 kHz for 30 min, add ethanolamine solution at 1-3% mass fraction at 1.5 times the mass of polylactic acid at a rate of 8 ml / min, continue the reaction for 30 min, transfer to a freezer at -45°C and freeze for 12 h, then place in a freezer at -5°C for extraction for 5 days, changing the water three times a day during extraction, and finally freeze-dry at -60°C. Hydroxylactic acid was obtained by freeze drying in a dryer; dichloromethane, dimethylformamide, hydroxyl polylactic acid and 4-guanidinophthalate were mixed in a mass ratio of 8:2:3:1.5 and stirred at 50 rpm for 3 h to obtain an electrospinning solution. Electrospinning was carried out with a receiving distance of 18 cm, a spinning solution injection rate of 3 mL / h, a relative humidity of 55%, a temperature of 27 °C and a polarity of 18 kV to obtain a composite membrane.

[0048] (5) Lay the lower layer, composite film and upper layer in sequence, scrape the edges, press for 5 minutes on a hot press at 120°C, cool to room temperature, soak in 95% acetone solution for 6 minutes, take out and air dry naturally to obtain breathable and elastic mask fabric.

[0049] Comparative Example 1

[0050] The formulation of Comparative Example 1 is the same as that of Example 2. The only difference between the preparation method of this breathable and highly elastic mask fabric and Example 2 is the difference in steps (1) and (2). Steps (1) and (2) are modified as follows:

[0051] (1) Silane coupling agent KH560, triethylenetetramine and anhydrous ethanol were mixed at a mass ratio of 1:2.2:18 and reacted at room temperature for 22 h to obtain solution A; graphene oxide and deionized water were mixed at a mass ratio of 1:18 and sonicated at 45 kHz for 0.5 h to obtain solution B; solution A and solution B were mixed at a mass ratio of 4.5:1, the pH was adjusted to 5 with acetic acid, the temperature was raised to 85 ℃ and reacted for 22 h. After the reaction was completed, the mixture was filtered and washed 6 times with anhydrous ethanol and deionized water. Finally, it was dried in a vacuum drying oven at 55 ℃ to constant weight to obtain amino graphene oxide.

[0052] (2) Polybutylene terephthalate, amino-based graphene oxide, and tannic acid were mixed in a mass ratio of 45:10:5 and placed in a high-speed mixer. The mixture was stirred at 105°C and 800 rpm for 15 minutes. The mixture was then transferred to a fiber drawing machine and drawn through a spinneret to form a long fiber web. The long fiber web was then hot-pressed into shape using a hot press. After cooling and setting, a weight of 40 g / m² was obtained. 2 The non-woven fabric is cut into the same size, which constitutes the upper and lower layers.

[0053] Comparative Example 2

[0054] The formulation of Comparative Example 2 is the same as that of Example 2. The only difference between the preparation method of this breathable high-elastic mask fabric and Example 2 is that step (1) is omitted, and step (2) is modified as follows: polybutylene terephthalate, graphene oxide, and tannic acid are mixed in a mass ratio of 45:10:5 and placed in a high-speed mixer. The mixture is stirred at 105°C and 800 rpm for 15 minutes, and then transferred to a drawing machine. The fibers are drawn through a spinneret to form a long fiber web. The long fiber web is then hot-pressed and shaped by a hot press. After cooling and setting, a weight of 40 g / m² is obtained. 2 The non-woven fabric is cut into the same size, which constitutes the upper and lower layers.

[0055] Comparative Example 3

[0056] The formulation of Comparative Example 3 is the same as that of Example 2. The only difference between the preparation method of this breathable and high-elastic mask fabric and Example 2 is the difference in step (2). Step (2) is modified as follows: polybutylene terephthalate and modified graphene oxide are mixed at a mass ratio of 45:10 and placed in a high-speed mixer. The mixture is stirred at 105°C and 800 rpm for 15 minutes. Then it is transferred to a drawing machine and drawn through a spinneret to form a long fiber web. The long fiber web is hot-pressed by a hot press and cooled to set, resulting in a basis weight of 40 g / m². 2The non-woven fabric is cut into the same size, which constitutes the upper and lower layers;

[0057] Comparative Example 4

[0058] The formulation of Comparative Example 4 is the same as that of Example 2. The only difference between the preparation method of this breathable and elastic mask fabric and Example 2 is that the treatment in (3) is not performed, and step (4) is modified as follows: polylactic acid is dispersed in 1,4-dioxane at 13 times the mass of polylactic acid, heated to 55°C, sonicated at 45 kHz for 20 min, and ethanolamine solution with a mass fraction of 2% at 1.4 times the mass of polylactic acid is added dropwise at a rate of 6 ml / min. The reaction is continued for 25 min, transferred to a freezer at -43°C and frozen for 11 h, and then placed in a freezer at -4°C. Extraction was performed for 4 days, with water changed three times a day during extraction. Finally, the mixture was freeze-dried in a freeze dryer at -55℃ to obtain hydroxyl polylactic acid. Dichloromethane, dimethylformamide, and hydroxyl polylactic acid were mixed at a mass ratio of 8:2:2 and stirred at 40 rpm for 2 hours to prepare an electrospinning solution. Electrospinning was then performed with a receiving distance of 15-18 cm, a spinning solution injection rate of 2 mL / h, a relative humidity of 50%, a temperature of 25℃, and an electrode voltage of 16 kV to obtain a composite membrane.

[0059] Comparative Example 5

[0060] The formulation composition of Comparative Example 5 is the same as that of Example 2. The only difference between the preparation method of this breathable and high-elastic mask fabric and Example 2 is the difference in step (5). Step (5) is modified as follows: lay the lower layer, composite film and upper layer in sequence, scrape the edge, and then hot press for 5 minutes on a hot press at 120°C. After cooling to room temperature, the breathable and high-elastic mask fabric is obtained.

[0061] Example of effect

[0062] Table 1 below shows the performance analysis results of the breathable and highly elastic mask fabrics of Examples 1, 2, and 3 and Comparative Examples 1, 2, 3, 4, and 5 of the present invention.

[0063] Table 1

[0064] Elongation at break (%) Oxygen index (%) Antibacterial rate (%) Air permeability (mm / s) Water contact angle (°) Example 1 479 38.9 99 326 15 Example 2 485 39.2 99 315 22 Example 3 477 38.5 99 320 18 Comparative Example 1 441 38,1 99 315 19 Comparative Example 2 415 26.5 99 318 23 Comparative Example 3 478 30.1 98 320 20 Comparative Example 4 469 37.4 75 253 19 Comparative Example 5 478 37.8 99 319 38

[0065] By comparing the experimental data of the examples and comparative examples in Table 1, it can be clearly found that the breathable and elastic mask fabrics prepared in Examples 1, 2 and 3 have better elasticity, heat resistance, breathability, antibacterial properties and stain resistance.

[0066] A comparison of the experimental data from Examples 1, 2, and 3 and Comparative Examples 1, 2, and 3 reveals that, in the preparation of polybutylene terephthalate composite masterbatch for upper and lower layers of nonwoven fabrics, the introduction of modified graphene oxide, the interaction between calcium ions and amino-based graphene oxide sheets, improves the elasticity of the nonwoven fabric; the introduction of pyridine enhances hydrophilicity; and the use of tannic acid to crosslink modified graphene oxide onto polybutylene terephthalate increases crystallinity and improves the heat resistance of the nonwoven fabric. From Examples 1, 2, and 3, and Comparative Examples 1, 2, and 3, it can be found that... Comparison of experimental data from Example 3 and Comparative Examples 4 and 5 reveals that the composite membrane made from hydroxyl polylactic acid and 4-guanidinophthalate has good antibacterial properties. Furthermore, 4-guanidinophthalate can reduce the spacing between porous microfibers, enhancing filtration performance. When the upper and lower layers and the middle layer of the composite membrane are bonded together, acetone is used for swelling treatment to enhance breathability. After swelling, nano-protrusions are formed on the surface of the nonwoven fabric, allowing the hydrophilic upper and lower layers to form a hydration layer, thus giving the mask fabric anti-fouling properties.

[0067] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No markings in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for preparing a breathable, highly elastic mask fabric, characterized in that, The method for preparing the breathable and highly elastic mask fabric includes the following specific steps: (1) Silane coupling agent KH560, triethylenetetramine, and anhydrous ethanol were mixed at a mass ratio of 1:2.2:18 and reacted at room temperature for 22 h to obtain solution A; graphene oxide and deionized water were mixed at a mass ratio of 1:18 and sonicated at 45 kHz for 0.5 h to obtain solution B; solution A and solution B were mixed at a mass ratio of 4.5:1, the pH was adjusted to 5 with acetic acid, and the temperature was raised to 85 ℃ for 22 h. After the reaction was completed, the mixture was filtered and washed 6 times with anhydrous ethanol and deionized water. Finally, it was dried in a vacuum drying oven at 55 ℃ to constant weight to obtain amino-based graphene oxide; pyridine-2,3 - A mixture of pyridine-2,3-dicarboxylic acid and anhydrous ethanol at a mass ratio of 3:18 was prepared, and the pH was adjusted to 6.5 with ammonia. A 5% calcium nitrate ethanol solution was added dropwise at a rate of 6 ml / min. The molar ratio of pyridine-2,3-dicarboxylic acid to calcium nitrate was 3:2.

1. The pH was adjusted to 6.5 with ammonia. Then, amino-2,3-dicarboxylic acid graphene oxide was added in a mass ratio of 4:

18. The mixture was stirred at 60 rpm for 30 h. After the reaction, the mixture was allowed to stand for 6 h. The mixture was then filtered and washed 4 times with anhydrous ethanol, and then washed twice with acetone. The mixture was then transferred to a drying oven at 55 °C and dried to constant weight to obtain modified graphene oxide. (2) Polybutylene terephthalate, modified graphene oxide, and tannic acid were mixed in a mass ratio of 45:10:5 and placed in a high-speed mixer. The mixture was stirred at 105°C and 800 rpm for 15 minutes. The mixture was then transferred to a fiber drawing machine and drawn through a spinneret to form a long fiber web. The long fiber web was then hot-pressed into shape using a hot press. After cooling and setting, a weight of 40 g / m² was obtained. 2 The non-woven fabric is cut into the same size, which are the upper and lower layers; (3) Under ice bath conditions, thiourea dioxide was mixed with a 2% peracetic acid solution and reacted for 3-3.5 h. After filtration and washing four times with anhydrous ethanol, the mixture was dried to constant weight in a vacuum drying oven at 55 °C to obtain thiourea trioxide. Deionized water, potassium carbonate, and 4-aminophthalic acid were mixed and stirred until dissolved in a mass ratio of 7.5:1.2:

2. Thiourea trioxide was added in 6 portions at 13-fold intervals, with a mass ratio of 0.85 times that of 4-aminophthalic acid. After the addition was completed, the reaction was carried out at room temperature for 5 hours, then allowed to stand for 24 hours. The mixture was filtered and washed four times with acetone. It was then dispersed in deionized water at a mass of 9 times that of 4-aminophthalic acid, heated to 85°C, stirred until dissolved, and 0.45 times that of 4-aminophthalic acid at a mass fraction of 37% hydrochloric acid was added. The reaction was carried out for 0.5 hours, then filtered while hot and allowed to stand for 11 hours. The mixture was then cooled to 4°C, filtered, and vacuum dried at 85°C to obtain 4-guanidinophthalic acid salt. (4) Disperse polylactic acid in 1,4-dioxane at 13 times the mass of polylactic acid, heat to 55℃, sonicate at 45kHz for 20min, add ethanolamine solution at 1.4 times the mass of polylactic acid with a mass fraction of 2% at a rate of 6ml / min, continue the reaction for 25min, transfer to a freezer at -43℃ and freeze for 11h, then place in a freezer at -4℃ for extraction for 4d, change the water three times a day during extraction, and finally freeze dry in a freeze dryer at -55℃ to obtain hydroxyl polylactic acid; mix dichloromethane, dimethylformamide, hydroxyl polylactic acid and 4-guanidinophthalate salt at a mass ratio of 8:2:2:1, stir at 40rpm for 2h to obtain electrospinning solution, perform electrospinning, the receiving distance is 16cm, the injection speed of the spinning solution is 2mL / h, the relative humidity is 50%, the temperature is 25℃, and the polar voltage is 16kV to obtain composite membrane; (5) Lay the lower layer, composite film and upper layer in sequence, scrape the edges, press for 4 minutes on a hot press at 105℃, cool to room temperature, soak in 93% acetone solution for 5 minutes, take out and air dry naturally to obtain breathable and elastic mask fabric.