Waterproof and breathable polyester-based sheet fabric and preparation method thereof

Abstract

The application relates to the technical field of layered materials, and discloses a waterproof and breathable polyester-based layered fabric and a preparation method thereof. The preparation method of the waterproof and breathable polyester-based layered fabric comprises the following steps: preparing polyurethane spinning solution by taking polyurethane, polyethylene glycol and a crosslinking agent as raw materials; electrospinning the polyurethane spinning solution and performing heat treatment to obtain a waterproof and breathable polyurethane film; preparing a hydrophobic finishing liquid by using a hydrophobic polyacrylate emulsion; immersing polyester fabric in the hydrophobic finishing liquid, performing two-dip-two-nip, pre-drying and baking to obtain modified polyester fabric; taking the waterproof and breathable polyurethane film as an inner layer, cotton fabric as an intermediate layer and the modified polyester fabric as an outer layer, and performing hot-pressing composite through polyamide hot melt adhesive to obtain the waterproof and breathable polyester-based layered fabric; the waterproof and breathable polyester-based layered fabric has a three-layer structure, and the three layers are mutually cooperative and have function superposition; the waterproof and breathable performance is improved, and the waterproof and breathable polyester-based layered fabric is also endowed with good antibacterial performance, mechanical performance and soft hand feeling.

Description

Technical Field

[0001] This invention relates to the field of layered materials technology, specifically to a waterproof and breathable polyester base layered fabric and its preparation method. Background Technology

[0002] With the continuous improvement of people's living standards and the progress of the textile industry, the basic functions of traditional textiles in covering the body and keeping warm can no longer meet people's needs. As a result, various intelligent and functional textiles have received widespread attention and development. In daily life and work, people inevitably encounter some harsh climates or environments, such as exploration, medical use, military missions, and outdoor recreation. This requires our clothing to meet specific functions under special conditions while still maintaining its original comfort. Waterproof and breathable clothing is a prominent example. On the one hand, it must prevent the penetration of rain and snow, and on the other hand, it must allow the body's sweat to be expelled through the fabric in the form of gas.

[0003] Polyester fabric has advantages such as high strength, low shrinkage, low price, and abrasion resistance, making it a commonly used fabric. However, its poor moisture absorption and lack of waterproof and breathable properties limit its application. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a method for preparing a waterproof and breathable polyester base fabric, comprising the following steps: Step 1: Prepare a polyurethane spinning solution using polyurethane, polyethylene glycol, and a crosslinking agent as raw materials; electrospin the polyurethane spinning solution and heat-treat it to obtain a polyurethane waterproof and breathable membrane. The polyurethane is obtained by reacting polybutane 2000, isophorone diisocyanate, hydrophobically modified diol, 2,2-dimethylolpropionic acid, and triethylamine; the modified diol is obtained by reacting modified polydimethylsiloxane with a diol; the diol is obtained by reacting furfural with 2-amino-2-methyl-1,3-propanediol; and the modified polydimethylsiloxane is obtained by reacting hydroxyl-terminated polydimethylsiloxane with toluene diisocyanate. Step 2: Prepare a hydrophobic finishing solution using a hydrophobic polyacrylate emulsion; immerse the polyester fabric in the hydrophobic finishing solution, perform two dips and two squeegees, pre-dry and bake to obtain the modified polyester fabric. The hydrophobic polyacrylate emulsion is obtained by polymerization of butyl acrylate, methyl methacrylate, hydroxyethyl methacrylate, 2-(perfluorooctyl)ethyl methacrylate, vinyltrimethoxysilane, and allyltrimethylammonium chloride. Step 3: Using a polyurethane waterproof and breathable membrane as the inner layer, cotton fabric as the middle layer, and modified polyester fabric as the outer layer, a waterproof and breathable polyester base fabric is obtained by hot-pressing with polyamide hot melt adhesive.

[0005] Preferably, in step one, the concentration of the polyurethane spinning solution is 10-15 wt%; the content of polyethylene glycol in the polyurethane spinning solution is 0.15-0.25 wt%; the amount of crosslinking agent is 2-4 wt% of the amount of polyurethane; the crosslinking agent includes polyaziridinium crosslinking agent SaC-100; the heat treatment conditions are: temperature 60-100℃, time 2h.

[0006] Preferably, in step one, the thickness of the polyurethane waterproof and breathable membrane is 62-68µm and the porosity is 70-76%.

[0007] Preferably, in step one, the electrospinning conditions are: humidity of 30-40% RH, temperature of 28-32℃, extrusion rate of 0.15mm / min, and distance from needle tip to receiver of 26cm.

[0008] In the above process, a polyurethane waterproof and breathable membrane is prepared by electrospinning. Through reasonable structural design, the polyurethane waterproof and breathable membrane has the characteristics of small pore size and high porosity. The interconnected pores between the stacked fiber layers endow it with excellent moisture permeability and air permeability, which is conducive to the transmission of air and water. Among them, the polyethylene glycol and polyurethane are sufficiently entangled to form a homogeneous fiber structure. A small amount of polyethylene glycol helps to improve the overall performance of the polyurethane waterproof and breathable membrane. In addition, during the heat treatment process, the aziridine functional groups in the polyaziridine crosslinking agent SaC-100 are opened by thermal induced reaction and crosslinked with the carboxyl groups in the polyurethane, which increases the porosity of the membrane. Furthermore, the DA bond is broken, which allows the polysiloxane segments to migrate to the surface of the polyurethane waterproof and breathable membrane, enhancing its hydrophobicity. Therefore, the polyurethane waterproof and breathable membrane has excellent mechanical properties, air permeability, and moisture permeability and hydrophobicity.

[0009] Preferably, in step one, the polyurethane is prepared by: Polybutanediol 2000, isophorone diisocyanate, and hydrophobically modified diol are mixed and preheated at 73-77℃ for 20-40 min. The temperature is then raised to 84-88℃, bismuth 2-ethylhexanoate is added, and the reaction continues for 2-3 h to obtain a prepolymer. 2,2-dimethylolpropionic acid is then added, and the reaction continues for 3-4 h. The temperature is lowered to 45℃, triethylamine is added, and the reaction is neutralized for 10 min to obtain polyurethane. The mass ratio of polybutanediol 2000, isophorone diisocyanate, hydrophobically modified diol, bismuth 2-ethylhexanoate, 2,2-dimethylolpropionic acid, and triethylamine is (49.4-49.8):(16.2-17.0):(6-9):(0.08-0.12):(5.94-6.53):(4.48-4.93). In the above process, polyurethane containing hydrophobic polysiloxane segments and DA bonds is obtained by reacting polybutane 2000, isophorone diisocyanate, hydrophobically modified diol, 2,2-dimethylolpropionic acid and triethylamine.

[0010] Preferably, in step one, the method for preparing the hydrophobically modified diol is as follows: Hydroxyl-terminated polydimethylsiloxane and toluene diisocyanate were added to toluene and stirred. Then, dibutyltin dilaurate was added and stirred at 60-66℃ for 6-8 hours. Then, N-(2-hydroxyethyl)maleimide and dibutyltin dilaurate were added, and the temperature was kept constant. The stirring was continued for 12-16 hours. After purification, modified polydimethylsiloxane was obtained. The mass ratio of hydroxyl-terminated polydimethylsiloxane, toluene diisocyanate, toluene, dibutyltin dilaurate, and N-(2-hydroxyethyl)maleimide was (11-22):(0.88-1.76):(20-30):(0.06-0.1):(0.71-1.42). In a nitrogen atmosphere, furfural and 2-amino-2-methyl-1,3-propanediol were added to ethanol, stirred, and reacted at 60-70℃ for 4-8 h. After purification, a diol was obtained. The mass ratio of furfural, 2-amino-2-methyl-1,3-propanediol, and ethanol was (4.8-9.61):(5.26-10.51):(240-320). Modified polydimethylsiloxane was added to toluene and stirred. Then, a diol was added and stirred. The mixture was reacted at 72-78℃ for 20-30 h and purified to obtain a hydrophobic modified diol. The mass ratio of the modified polydimethylsiloxane, toluene, and diol was (5.4-10.8):(30-40):(1.83-3.66). In the above process, hydroxyl-terminated polydimethylsiloxane, N-(2-hydroxyethyl)maleimide, and toluene diisocyanate are combined through the reaction between the isocyanate group and the hydroxyl group to obtain modified polydimethylsiloxane; furfural and 2-amino-2-methyl-1,3-propanediol are combined through Schiff base reaction to obtain a diol; then, the furan ring in the diol and the maleimide in the modified polydimethylsiloxane are introduced into the hydrophobic modified diol through Diels-Alder (DA) reaction to introduce the polydimethylsiloxane structure and DA bond.

[0011] Preferably, in step two, the preparation method of the hydrophobic polyacrylate emulsion is as follows: A composite emulsifier is obtained by mixing fatty alcohol polyoxyethylene ether and sodium dodecyl sulfate in an equal mass ratio; the composite emulsifier is then mixed with deionized water in a mass ratio of (0.64-0.92):(190-210) to obtain an emulsifier mixture; butyl acrylate, methyl methacrylate, hydroxyethyl methacrylate, 2-(perfluorooctyl)ethyl methacrylate, vinyltrimethoxysilane, and allyltrimethylammonium chloride are mixed in a mass ratio of (30-45):(20-30):(2-3):(15-20):(3-4):(3.5-7.5) to obtain a mixed monomer. In a nitrogen atmosphere, the above emulsifier mixture is heated to 50-55°C, a portion of potassium persulfate aqueous solution is added, followed by a portion of mixed monomers. The reaction is carried out for 20-30 minutes, then the temperature is raised to 75-80°C. The remaining potassium persulfate aqueous solution is added dropwise first, and the temperature is maintained for 20-30 minutes. Then the remaining mixed monomers are added dropwise, and the temperature is maintained for 40-60 minutes. After the reaction is completed, the temperature is lowered to 25°C, and the mixture is filtered to obtain a hydrophobic polyacrylate emulsion. The mass ratio of the composite emulsifier, mixed monomers, and potassium persulfate is (5-5.5):(70-102):(1-1.2). In the above process, butyl acrylate, methyl methacrylate, and hydroxyethyl methacrylate are used as polymerizing monomers, and 2-(perfluorooctyl)ethyl methacrylate, vinyltrimethoxysilane, and allyltrimethylammonium chloride are used as functional monomers. A small amount of hydroxyethyl methacrylate is added to the above functional monomers and condenses to form ether bonds under heating, forming a film on the fiber surface to prevent water penetration and improve the waterproof performance of the finished fabric. The quaternary ammonium salt structure of allyltrimethylammonium chloride can endow the finished fabric with antibacterial properties. Introducing 2-(perfluorooctyl)ethyl methacrylate and vinyltrimethoxysilane into polyacrylate concentrates the advantages of fluorosilicone, so that the hydrophobic polyacrylate emulsion can improve the waterproof performance of the fabric while also enhancing the softness of the fabric.

[0012] Preferably, in step two, the concentration of the hydrophobic finishing solution is 60-80 g / L; the conditions for the two dips and two nips are: immersion time is 20-30 min, and the roll-off rate is 70-80%.

[0013] Preferably, in step two, the pre-baking conditions are: temperature 80℃, time 3min; the baking conditions are: temperature 150℃, time 4min.

[0014] Preferably, in step two, the weight of the polyester fabric is 60-80 g / m². 2 .

[0015] Preferably, in step three, the hot-pressing composite conditions are: temperature 120-140℃, hot-pressing time 12-20s, and hot-pressing pressure 35-42Pa. Preferably, in step three, the weight of the cotton fabric is 50-60 g / m². 2 .

[0016] The waterproof and breathable polyester base fabric is prepared by the aforementioned method.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention discloses a waterproof and breathable polyester base layer fabric, which uses a polyurethane waterproof and breathable membrane as the inner layer, cotton fabric as the middle layer, and modified polyester fabric as the outer layer. The three layers work together to enhance the waterproof and breathable performance of the waterproof and breathable polyester base layer fabric, while also giving it good antibacterial properties, mechanical properties, and a soft hand feel.

[0018] 2. The polyurethane waterproof and breathable membrane of the present invention is obtained by electrospinning and heat treatment of a polyurethane spinning solution containing polyurethane, polyethylene glycol, and a crosslinking agent. The polyurethane contains hydrophobic polysiloxane segments, which, during electrospinning, form a uniformly porous and hydrophobic fiber membrane with polyethylene glycol. Then, during heat treatment, the crosslinking agent further improves the mechanical properties, breathability, and moisture permeability and waterproof performance of the polyurethane waterproof and breathable membrane. The present invention uses cotton fabric as the middle layer. Cotton fabric has good hydrophilicity and moisture absorption and breathability, forming a hydrophilic-hydrophobic gradient difference with the polyurethane waterproof and breathable membrane, which is conducive to promoting the expulsion of moisture.

[0019] 3. The modified polyester fabric of the present invention is obtained by treating with a hydrophobic finishing agent containing a hydrophobic polyacrylate emulsion. The hydrophobic polyacrylate emulsion uses butyl acrylate, methyl methacrylate, and hydroxyethyl methacrylate as polymer monomers, and 2-(perfluorooctyl)ethyl methacrylate, vinyltrimethoxysilane, and allyltrimethylammonium chloride as functional monomers. The presence of a small amount of hydroxyethyl methacrylate and functional monomers makes the modified polyester fabric not only have good waterproof performance, but also have certain antibacterial properties and a soft hand feel. Attached Figure Description

[0020] Figure 1 These are comparative hydrostatic pressure test images of the waterproof and breathable polyester base layer fabrics prepared in Examples 1-3 and Comparative Examples 1-3 of the present invention. Figure 2 This is a schematic diagram illustrating the synthesis of the modified polydimethylsiloxane of the present invention; Figure 3 This is a schematic diagram of the synthesis of the diol of the present invention; Figure 4 This is a schematic diagram illustrating the synthesis of the hydrophobically modified diol of the present invention. Detailed Implementation

[0021] 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. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0022] Example 1 This embodiment discloses a method for preparing a waterproof and breathable polyester base fabric, including the following steps: Step 1: Add 11g of hydroxyl-terminated polydimethylsiloxane and 0.88g of toluene diisocyanate to 20g of toluene, stir to dissolve, then add 0.03g of dibutyltin dilaurate, stir and react at 60℃ for 8h, then add 0.71g of N-(2-hydroxyethyl)maleimide and 0.03g of dibutyltin dilaurate, keep the temperature constant, and continue to stir and react for 16h. After the reaction is completed, remove the solvent by rotary evaporation to obtain modified polydimethylsiloxane; In a nitrogen atmosphere, 4.8 g of furfural and 5.26 g of 2-amino-2-methyl-1,3-propanediol were added to 240 g of ethanol, stirred, and reacted at 60 °C for 8 h. After the reaction was completed, the solvent was removed by rotary evaporation to obtain the diol. 5.4 g of modified polydimethylsiloxane was added to 30 g of toluene and stirred. Then 1.83 g of diol was added and stirred. The mixture was reacted at 72 °C for 30 h. After the reaction was completed, the solvent was removed by rotary evaporation to obtain the hydrophobic modified diol. 49.4g of polybutanediol 2000, 16.2g of isophorone diisocyanate, and 6g of hydrophobically modified diol were mixed and preheated at 73℃ for 40min. The temperature was then raised to 84℃, and 0.08g of bismuth 2-ethylhexanoate was added. The reaction was continued for 3h to obtain a prepolymer. Then, 5.94g of 2,2-dimethylolpropionic acid was added, and the reaction was continued for 4h. The temperature was lowered to 45℃, and 4.93g of triethylamine was added and neutralized for 10min to obtain polyurethane. Polyurethane was added to deionized water and emulsified at 1100 r / min for 40 min. Then, polyethylene glycol powder was added and stirred for 10 min. Next, polyaziridine crosslinking agent SaC-100 was added and stirred for 10 min. Finally, deionized water was added and stirred at 200 r / min for 3 h to obtain a polyurethane spinning solution with a concentration of 10 wt%. The polyurethane spinning solution contained 0.15 wt% polyethylene glycol and 2 wt% polyaziridine crosslinking agent SaC-100. The polyurethane spinning solution was electrospun, and the resulting original film was heat-treated at 60°C for 2 hours to obtain a polyurethane waterproof and breathable membrane with a thickness of 62µm. The electrospinning conditions were: humidity 30%RH, temperature 28°C, extrusion rate 0.15mm / min, and distance from needle tip to receiver 26cm. Step 2: Mix fatty alcohol polyoxyethylene ether and sodium dodecyl sulfate in equal mass ratio to obtain a composite emulsifier; add 0.64g of the composite emulsifier to 190g of deionized water and stir at 100r / min to obtain an emulsifier mixture; mix butyl acrylate, methyl methacrylate, hydroxyethyl methacrylate, 2-(perfluorooctyl)ethyl methacrylate, vinyltrimethoxysilane, and allyltrimethylammonium chloride in a mass ratio of 30:20:2:15:3:3.5 to obtain a mixed monomer. In a nitrogen atmosphere, the above emulsifier mixture was heated to 50°C, and 1 / 3 of the mass of potassium persulfate aqueous solution was added. Then, 10% of the mass of the mixed monomer was added dropwise, with the addition time controlled at 10 min. After the addition was complete, the reaction continued for 20 min. The temperature was then raised to 75°C, and the remaining potassium persulfate aqueous solution was added dropwise first, and the temperature was maintained for 30 min. Then, the remaining mixed monomer was added dropwise, with the addition time controlled at 90 min, and the temperature was maintained for 60 min. After the reaction was complete, the temperature was lowered to 25°C, and the mixture was filtered to obtain a hydrophobic polyacrylate emulsion. The mass ratio of the composite emulsifier, mixed monomer, and potassium persulfate was 5:70:1.2. A hydrophobic polyacrylate emulsion was mixed with deionized water to obtain a hydrophobic finishing solution with a concentration of 60 g / L. A polyester fabric was immersed in the hydrophobic finishing solution, subjected to two dips and two nips, pre-drying, and baking to obtain a modified polyester fabric. The polyester fabric had a basis weight of 60 g / m². The conditions for the two dips and two nips were: immersion time of 20 min and a nip-off rate of 70%; pre-drying conditions: temperature of 80℃ and time of 3 min; baking conditions: temperature of 150℃ and time of 4 min.

[0023] Step 3: Using a polyurethane waterproof and breathable membrane as the inner layer, cotton fabric as the middle layer, and modified polyester fabric as the outer layer, a waterproof and breathable polyester base fabric is obtained by hot-pressing with polyamide hot melt adhesive; wherein, the hot-pressing conditions are: temperature of 120℃, hot-pressing time of 20s, and hot-pressing pressure of 35Pa; the weight of the cotton fabric is 50g / m2.

[0024] Example 2 This embodiment discloses a method for preparing a waterproof and breathable polyester base fabric, including the following steps: Step 1: Add 22g of hydroxyl-terminated polydimethylsiloxane and 1.76g of toluene diisocyanate to 30g of toluene, stir to dissolve, then add 0.05g of dibutyltin dilaurate, stir and react at 66℃ for 6h, then add 1.42g of N-(2-hydroxyethyl)maleimide and 0.05g of dibutyltin dilaurate, keep the temperature constant, and continue to stir and react for 12h. After the reaction is completed, remove the solvent by rotary evaporation to obtain modified polydimethylsiloxane; In a nitrogen atmosphere, 9.61 g of furfural and 10.51 g of 2-amino-2-methyl-1,3-propanediol were added to 320 g of ethanol, stirred, and reacted at 70 °C for 4 h. After the reaction was completed, the solvent was removed by rotary evaporation to obtain the diol. 10.8g of modified polydimethylsiloxane was added to 40g of toluene and stirred. Then 3.66g of diol was added and stirred. The mixture was reacted at 78℃ for 20h. After the reaction was completed, the solvent was removed by rotary evaporation to obtain the hydrophobic modified diol. 9.8g of polybutanediol 2000, 17.0g of isophorone diisocyanate, and 9g of hydrophobically modified diol were mixed and preheated at 77℃ for 20min. The temperature was then raised to 88℃, and 0.12g of bismuth 2-ethylhexanoate was added. The reaction was continued for 2h to obtain a prepolymer. Then, 6.53g of 2,2-dimethylolpropionic acid was added, and the reaction was continued for 3h. The temperature was lowered to 45℃, and 4.93g of triethylamine was added and neutralized for 10min to obtain polyurethane. Polyurethane was added to deionized water and emulsified at 1500 rpm for 20 min. Then, polyethylene glycol powder was added and stirred for 30 min. Next, polyaziridine crosslinking agent SaC-100 was added and stirred for 20 min. Finally, deionized water was added and stirred at 300 rpm for 2 h to obtain a polyurethane spinning solution with a concentration of 15 wt%. The polyurethane spinning solution contained 0.25 wt% polyethylene glycol and 4 wt% polyaziridine crosslinking agent SaC-100. The polyurethane spinning solution was electrospun, and the resulting original film was heat-treated at 100°C for 2 hours to obtain a polyurethane waterproof and breathable membrane with a thickness of 68µm. The electrospinning conditions were: humidity 40%RH, temperature 32°C, extrusion rate 0.15mm / min, and distance from needle tip to receiver 26cm. Step 2: Mix fatty alcohol polyoxyethylene ether and sodium dodecyl sulfate in equal mass ratio to obtain a composite emulsifier; add 0.92g of the composite emulsifier to 210g of deionized water and stir at a rate of 200r / min to obtain an emulsifier mixture; mix butyl acrylate, methyl methacrylate, hydroxyethyl methacrylate, 2-(perfluorooctyl)ethyl methacrylate, vinyltrimethoxysilane, and allyltrimethylammonium chloride in a mass ratio of 30:20:2:15:3:7.5 to obtain a mixed monomer; In a nitrogen atmosphere, the above emulsifier mixture was heated to 55°C, and 1 / 3 of the mass of potassium persulfate aqueous solution was added. Then, 10% of the mass of the mixed monomer was added dropwise, with the addition time controlled at 20 min. After the addition was completed, the reaction continued for 30 min. The temperature was then raised to 80°C, and the remaining potassium persulfate aqueous solution was added dropwise first, and the temperature was maintained for 20 min. Then, the remaining mixed monomer was added dropwise, with the addition time controlled at 150 min, and the temperature was maintained for 40 min. After the reaction was completed, the temperature was lowered to 25°C, and the mixture was filtered to obtain a hydrophobic polyacrylate emulsion. The mass ratio of the composite emulsifier, mixed monomer, and potassium persulfate was 5.5:102:1.2. A hydrophobic polyacrylate emulsion was mixed with deionized water to obtain a hydrophobic finishing solution with a concentration of 80 g / L. Polyester fabric was immersed in the hydrophobic finishing solution, subjected to two dips and two nips, pre-drying, and baking to obtain modified polyester fabric. The polyester fabric had a basis weight of 80 g / m². The conditions for the two dips and two nips were: immersion time of 30 min and a nip rate of 80%; pre-drying conditions: temperature of 80℃ and time of 3 min; baking conditions: temperature of 150℃ and time of 4 min.

[0025] Step 3: Using a polyurethane waterproof and breathable membrane as the inner layer, cotton fabric as the middle layer, and modified polyester fabric as the outer layer, a waterproof and breathable polyester base fabric is obtained by hot-pressing with polyamide hot melt adhesive; wherein, the hot-pressing conditions are: temperature of 140℃, hot-pressing time of 12s, and hot-pressing pressure of 42Pa; the weight of the cotton fabric is 60g / m2.

[0026] Example 3 This embodiment discloses a method for preparing a waterproof and breathable polyester base fabric, including the following steps: Step 1: Add 16.5g of hydroxyl-terminated polydimethylsiloxane and 1.32g of toluene diisocyanate to 25g of toluene, stir to dissolve, then add 0.04g of dibutyltin dilaurate, stir and react at 63℃ for 7h, then add 1.07g of N-(2-hydroxyethyl)maleimide and 0.04g of dibutyltin dilaurate, keep the temperature constant, and continue to stir and react for 14h. After the reaction is completed, remove the solvent by rotary evaporation to obtain modified polydimethylsiloxane; In a nitrogen atmosphere, 7.21 g of furfural and 7.89 g of 2-amino-2-methyl-1,3-propanediol were added to 280 g of ethanol, stirred, and reacted at 65 °C for 6 h. After the reaction was completed, the solvent was removed by rotary evaporation to obtain the diol. 8.1g of modified polydimethylsiloxane was added to 35g of toluene and stirred. Then 2.75g of diol was added and stirred. The mixture was reacted at 75°C for 25h. After the reaction was completed, the solvent was removed by rotary evaporation to obtain the hydrophobic modified diol. 49.6g of polybutanediol 2000, 16.6g of isophorone diisocyanate, and 7.5g of hydrophobically modified diol were mixed and preheated at 75℃ for 30min. The temperature was then raised to 86℃, and 0.1g of bismuth 2-ethylhexanoate was added. The reaction was continued for 2.5h to obtain a prepolymer. Then, 6.24g of 2,2-dimethylolpropionic acid was added, and the reaction was continued for 3.5h. The temperature was lowered to 45℃, and 4.71g of triethylamine was added and neutralized for 10min to obtain polyurethane. Polyurethane was added to deionized water and emulsified at 1300 r / min for 30 min. Then, polyethylene glycol powder was added and stirred for 20 min. Next, polyaziridine crosslinking agent SaC-100 was added and stirred for 15 min. Finally, deionized water was added and stirred at 250 r / min for 2.5 h to obtain a polyurethane spinning solution with a concentration of 12.5 wt%. The polyurethane spinning solution contained 0.2 wt% polyethylene glycol and 3 wt% polyaziridine crosslinking agent SaC-100. The polyurethane spinning solution was electrospun, and the resulting original film was heat-treated at 80°C for 2 hours to obtain a polyurethane waterproof and breathable membrane with a thickness of 66µm. The electrospinning conditions were: humidity 35%RH, temperature 30°C, extrusion rate 0.15mm / min, and distance from needle tip to receiver 26cm. Step 2: Mix fatty alcohol polyoxyethylene ether and sodium dodecyl sulfate in equal mass ratio to obtain a composite emulsifier; add 0.78g of the composite emulsifier to 200g of deionized water and stir at 150r / min to obtain an emulsifier mixture; mix butyl acrylate, methyl methacrylate, hydroxyethyl methacrylate, 2-(perfluorooctyl)ethyl methacrylate, vinyltrimethoxysilane, and allyltrimethylammonium chloride in a mass ratio of 30:20:2:15:3:5.5 to obtain a mixed monomer; In a nitrogen atmosphere, the above emulsifier mixture was heated to 52.5°C, and 1 / 3 of the mass of potassium persulfate aqueous solution was added. Then, 10% of the mass of the mixed monomer was added dropwise, with the addition time controlled at 15 min. After the addition was completed, the reaction continued for 25 min. The temperature was then raised to 77.5°C, and the remaining potassium persulfate aqueous solution was added dropwise first, and the temperature was maintained for 25 min. Then, the remaining mixed monomer was added dropwise, with the addition time controlled at 120 min, and the temperature was maintained for 50 min. After the reaction was completed, the temperature was lowered to 25°C, and the mixture was filtered to obtain a hydrophobic polyacrylate emulsion. The mass ratio of the composite emulsifier, mixed monomer, and potassium persulfate was 5.25:86:1.1. A hydrophobic polyacrylate emulsion was mixed with deionized water to obtain a hydrophobic finishing solution with a concentration of 70 g / L. Polyester fabric was immersed in the hydrophobic finishing solution, subjected to two dips and two nips, pre-drying, and baking to obtain modified polyester fabric. The polyester fabric had a basis weight of 70 g / m². The conditions for the two dips and two nips were: immersion time of 25 min and a nip rate of 75%; pre-drying conditions: temperature of 80℃ and time of 3 min; baking conditions: temperature of 150℃ and time of 4 min.

[0027] Step 3: Using a polyurethane waterproof and breathable membrane as the inner layer, cotton fabric as the middle layer, and modified polyester fabric as the outer layer, a waterproof and breathable polyester base layer fabric is obtained by hot-pressing with polyamide hot melt adhesive; wherein, the hot-pressing conditions are: temperature of 130℃, hot-pressing time of 16s, and hot-pressing pressure of 38Pa; the weight of the cotton fabric is 55g / m2.

[0028] Comparative Example 1 Compared with Example 3, Comparative Example 1 used an equal amount of polybutanediol 2000 instead of hydrophobic modified diol in the preparation of polyurethane, while other conditions remained unchanged.

[0029] Comparative Example 2 Compared with Example 3, in the process of preparing polyurethane waterproof and breathable membrane, Comparative Example 2 did not perform heat treatment on the original membrane after electrospinning the polyurethane spinning solution, and all other conditions remained unchanged.

[0030] Comparative Example 3 Compared with Example 3, Comparative Example 3 used polyester fabric instead of modified polyester fabric in the process of preparing waterproof and breathable polyester base layer fabric, while keeping other conditions unchanged.

[0031] In the above examples and comparative examples, the hydroxyl-terminated polydimethylsiloxane, with a hydroxyl content of 6-12%, was sourced from Hubei Xinyuhong Biomedical Technology Co., Ltd.; polybutane glycol 2000, also known as PTMG-2000, with catalog number PTMG2000, was sourced from Greenlink (Jining) Chemical Technology Co., Ltd.; polyethylene glycol powder, with a molecular weight of 2000-20000, was sourced from Jiangsu Haian Petrochemical Plant; and polyaziridine crosslinking agent SaC-100, with a purity of 99%, was sourced from Guangzhou Yuanda New Materials Co., Ltd.

[0032] Experimental Example Performance tests were conducted on the waterproof and breathable polyester base fabrics prepared in Examples 1-3 and Comparative Examples 1-3: I. Waterproof performance test: The test was conducted according to the method of standard GB / T 4744—2013 "Test and evaluation of waterproof performance of textiles"; II. Air permeability test: The YG461E-III fully automatic air permeability meter was used for testing.

[0033] The test results are shown in Table 1: Table 1

[0034] As can be seen from the test results in Table 1, the waterproof and breathable polyester base layer fabrics prepared in Examples 2-4 of the present invention have excellent waterproof and breathable properties. As can be seen from the comparison between Comparative Example 1 and Example 3, the siloxane segments introduced by hydrophobic diols in the polyurethane spinning solution of the present invention have a positive effect on improving the waterproof performance of the fabric. As can be seen from the comparison between Comparative Example 2 and Example 3, in the preparation process of the polyurethane waterproof and breathable membrane of the present invention, during the heat treatment process, the aziridine functional group in the polyaziridine crosslinking agent SaC-100 is opened by the heat-induced effect and crosslinked with the carboxyl group in the polyurethane, thereby increasing the porosity of the membrane. In addition, the DA bond is broken, which makes the polysiloxane chain segments migrate to the surface of the polyurethane waterproof and breathable membrane, enhancing its hydrophobicity and improving the waterproof and breathable performance of the polyurethane waterproof and breathable membrane, thereby improving the waterproof and breathable performance of the waterproof and breathable polyester base layer fabric. As can be seen from the comparison between Comparative Example 3 and Example 3, the modified polyester fabric of the present invention has improved waterproof performance after being treated with a hydrophobic finishing agent. However, the coating formed by the hydrophobic polyacrylate emulsion blocks the pore structure in the fabric, which leads to a decrease in its breathability.

[0035] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a waterproof and breathable polyester base-textured fabric, characterized in that, Includes the following steps: Step 1: Prepare a polyurethane spinning solution using polyurethane, polyethylene glycol, and a crosslinking agent as raw materials; electrospin the polyurethane spinning solution and heat-treat it to obtain a polyurethane waterproof and breathable membrane. The polyurethane is obtained by reacting polybutane 2000, isophorone diisocyanate, hydrophobically modified diol, 2,2-dimethylolpropionic acid, and triethylamine; the modified diol is obtained by reacting modified polydimethylsiloxane with a diol; the diol is obtained by reacting furfural with 2-amino-2-methyl-1,3-propanediol; and the modified polydimethylsiloxane is obtained by reacting hydroxyl-terminated polydimethylsiloxane with toluene diisocyanate. Step 2: Prepare a hydrophobic finishing solution using a hydrophobic polyacrylate emulsion; immerse the polyester fabric in the hydrophobic finishing solution, perform two dips and two squeegees, pre-dry and bake to obtain the modified polyester fabric. The hydrophobic polyacrylate emulsion is obtained by polymerization of butyl acrylate, methyl methacrylate, hydroxyethyl methacrylate, 2-(perfluorooctyl)ethyl methacrylate, vinyltrimethoxysilane, and allyltrimethylammonium chloride. Step 3: Using a polyurethane waterproof and breathable membrane as the inner layer, cotton fabric as the middle layer, and modified polyester fabric as the outer layer, a waterproof and breathable polyester base fabric is obtained by hot-pressing with polyamide hot melt adhesive.

2. The method for preparing the waterproof and breathable polyester base-like fabric according to claim 1, characterized in that, In step one, the concentration of the polyurethane spinning solution is 10-15 wt%; the content of polyethylene glycol in the polyurethane spinning solution is 0.15-0.25 wt%, and the amount of crosslinking agent is 2-4 wt% of the amount of polyurethane; the crosslinking agent includes polyaziridinium crosslinking agent SaC-100; the heat treatment conditions are: temperature 60-100℃, time 2h.

3. The method for preparing the waterproof and breathable polyester base-like fabric according to claim 1, characterized in that, In step one, the thickness of the polyurethane waterproof and breathable membrane is 62-68µm, and the porosity is 70-76%.

4. The method for preparing the waterproof and breathable polyester base-like fabric according to claim 1, characterized in that, In step one, the electrospinning conditions are: humidity 30-40%RH, temperature 28-32℃, extrusion rate 0.15mm / min, and distance from needle tip to receiver 26cm.

5. The method for preparing the waterproof and breathable polyester base-like fabric according to claim 1, characterized in that, In step one, the polyurethane is prepared by the following method: Polybutanediol 2000, isophorone diisocyanate, and hydrophobically modified diol are mixed and preheated at 73-77℃ for 20-40 min. The temperature is then raised to 84-88℃, bismuth 2-ethylhexanoate is added, and the reaction continues for 2-3 h to obtain a prepolymer. Then, 2,2-dimethylolpropionic acid is added, and the reaction continues for 3-4 h. The temperature is lowered to 45℃, triethylamine is added, and the reaction is neutralized for 10 min to obtain polyurethane. The mass ratio of polybutanediol 2000, isophorone diisocyanate, hydrophobically modified diol, bismuth 2-ethylhexanoate, 2,2-dimethylolpropionic acid, and triethylamine is (49.4-49.8):(16.2-17.0):(6-9):(0.08-0.12):(5.94-6.53):(4.48-4.93).

6. The method for preparing the waterproof and breathable polyester base-like fabric according to claim 1, characterized in that, In step one, the preparation method of the hydrophobically modified diol is as follows: Hydroxyl-terminated polydimethylsiloxane and toluene diisocyanate were added to toluene and stirred. Then, dibutyltin dilaurate was added and stirred at 60-66℃ for 6-8 hours. Then, N-(2-hydroxyethyl)maleimide and dibutyltin dilaurate were added, and the temperature was kept constant. The stirring was continued for 12-16 hours. After purification, modified polydimethylsiloxane was obtained. The mass ratio of hydroxyl-terminated polydimethylsiloxane, toluene diisocyanate, toluene, dibutyltin dilaurate, and N-(2-hydroxyethyl)maleimide was (11-22):(0.88-1.76):(20-30):(0.06-0.1):(0.71-1.42). In a nitrogen atmosphere, furfural and 2-amino-2-methyl-1,3-propanediol were added to ethanol, stirred, and reacted at 60-70℃ for 4-8 h. After purification, a diol was obtained. The mass ratio of furfural, 2-amino-2-methyl-1,3-propanediol, and ethanol was (4.8-9.61):(5.26-10.51):(240-320). Modified polydimethylsiloxane was added to toluene and stirred. Then, diol was added and stirred. The mixture was reacted at 72-78℃ for 20-30 h and purified to obtain hydrophobic modified diol. The mass ratio of the modified polydimethylsiloxane, toluene and diol was (5.4-10.8):(30-40):(1.83-3.66).

7. The method for preparing the waterproof and breathable polyester base fabric according to claim 1, characterized in that, In step two, the preparation method of the hydrophobic polyacrylate emulsion is as follows: A composite emulsifier is obtained by mixing fatty alcohol polyoxyethylene ether and sodium dodecyl sulfate in an equal mass ratio; the composite emulsifier is then mixed with deionized water in a mass ratio of (0.64-0.92):(190-210) to obtain an emulsifier mixture; butyl acrylate, methyl methacrylate, hydroxyethyl methacrylate, 2-(perfluorooctyl)ethyl methacrylate, vinyltrimethoxysilane, and allyltrimethylammonium chloride are mixed in a mass ratio of (30-45):(20-30):(2-3):(15-20):(3-4):(3.5-7.5) to obtain a mixed monomer. In a nitrogen atmosphere, the above emulsifier mixture is heated to 50-55°C, a portion of potassium persulfate aqueous solution is added, followed by a portion of mixed monomers. The reaction is carried out for 20-30 minutes, and the temperature is raised to 75-80°C. The remaining potassium persulfate aqueous solution is added dropwise first, and the temperature is maintained for 20-30 minutes. Then, the remaining mixed monomers are added dropwise, and the temperature is maintained for 40-60 minutes. After the reaction is completed, the temperature is lowered to 25°C, and the mixture is filtered to obtain a hydrophobic polyacrylate emulsion. The mass ratio of the composite emulsifier, mixed monomers, and potassium persulfate is (5-5.5):(70-102):(1-1.2).

8. The method for preparing the waterproof and breathable polyester base fabric according to claim 1, characterized in that, In step two, the concentration of the hydrophobic finishing solution is 60-80 g / L; the conditions for the two dips and two nips are: immersion time is 20-30 min, and the roll-off rate is 70-80%.

9. The method for preparing the waterproof and breathable polyester base-like fabric according to claim 1, characterized in that, In step three, the hot-pressing composite conditions are: temperature 120-140℃, hot-pressing time 12-20s, and hot-pressing pressure 35-42Pa.

10. A sun-protective and waterproof layered composite fabric prepared by the method for preparing sun-protective and waterproof layered composite fabric as described in any one of claims 1-9.

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