Polyolefin waterproof and moisture permeable fabric manufacturing process

Abstract

The invention discloses a polyolefin waterproof and moisture permeable fabric manufacturing process, and relates to the technical field of waterproof fabrics, and the polyolefin waterproof and moisture permeable fabric manufacturing process comprises the following steps: step 1, preparing a polyolefin original film; step 2, blending modified resin: mixing matrix resin with a functional auxiliary agent to obtain a two-component modified resin system; step 3, coating and forming: uniformly coating the surface of the microporous expanded polyethylene original membrane with the two-component modified resin system to form a microporous communicated composite membrane material; step 4, post-treatment shaping: drying and cooling the microporous communicated composite membrane material to obtain a waterproof moisture-permeable base membrane; 5, fabric preparation, wherein the waterproof and moisture-permeable base film and base cloth are compounded, and the expanded polyethylene waterproof and moisture-permeable fabric is prepared through finishing; wherein the functional auxiliary agent is prepared from fluoroalkyl silane modified cross-linked PS (Polystyrene) microspheres and PEG (Polyethylene Glycol) coated nano TiO2. The waterproof and moisture-permeable expanded polyethylene fabric has the effects of remarkably improving the waterproof and moisture-permeable properties, washing resistance, micropore blockage resistance and mechanical strength of the waterproof and moisture-permeable expanded polyethylene fabric.

Description

Technical Field

[0001] This application relates to the field of waterproof fabric technology, and in particular to a manufacturing process for a polyolefin waterproof and breathable fabric. Background Technology

[0002] Waterproof and breathable fabrics are a type of functional fabric that combines the ability to block liquid water from entering while allowing gaseous water such as sweat to escape. They are widely used in outdoor sportswear such as windproof jackets, ski suits, protective clothing, tents, and bags.

[0003] In existing technologies, fluorinated coated fabrics, fluorine-free coated fabrics, and expanded polyethylene (ePE) fabrics are generally used as preparation methods for waterproof and breathable fabrics. Among these, ePE, an emerging technology, forms a dense microporous structure through a special stretching process. The micropore size is between that of water molecules and water vapor molecules, naturally achieving waterproof and breathable functions, and offering advantages such as lightweight, environmental friendliness, and lower cost. Furthermore, fabrics based on polyolefin films do not rely on fluorinated coatings, aligning with green development trends and becoming a research hotspot in recent years.

[0004] However, the surface structure stability of existing ePE-based fabrics is poor. After repeated washing, the micropores are prone to deformation or blockage, resulting in a sharp decline in waterproof and breathable performance, which makes it difficult to meet the durability requirements of outdoor clothing and needs to be improved. Summary of the Invention

[0005] In view of this, the purpose of this application is to provide a manufacturing process for polyolefin waterproof and breathable fabric, so as to effectively improve service life by improving water resistance and reducing moisture permeability. The specific solution is as follows:

[0006] A manufacturing process for a polyolefin waterproof and breathable fabric includes the following steps:

[0007] Step 1, Preparation of polyolefin base film: Polyethylene resin is extruded and stretched to obtain microporous expanded polyethylene base film;

[0008] Step 2, Modified Resin Formulation: Mix the base resin with functional additives to obtain a two-component modified resin system;

[0009] Step 3, Coating and Molding: The two-component modified resin system is uniformly coated onto at least one surface of the microporous expanded polyethylene original film using a coating process to form a microporous interconnected composite film material.

[0010] Step 4, Post-processing and shaping: The microporous interconnected composite membrane material is dried and cooled to obtain a waterproof and breathable base membrane;

[0011] Step 5, Fabric preparation: The waterproof and breathable base film is compounded with the base fabric, and after finishing, expanded polyethylene waterproof and breathable fabric is obtained.

[0012] The functional additives include fluorosilane-modified crosslinked PS microspheres and PEG-coated nano-TiO2.

[0013] Preferably, in step 1, the microporous expanded polyethylene film is a modified expanded polyethylene film, which is obtained by blending polyethylene resin with low surface energy grafted monomers and surface-modified nano-ceramic particles and then extruding and stretching them sequentially.

[0014] Preferably, the low surface energy grafted monomer is trifluoroethyl methacrylate or vinyltrimethoxysilane, and the addition amount is 2-5% of the polyethylene resin mass; the surface-modified nano-ceramic particles are modified nano-silica treated with KH550 surface modification, and the addition amount is 1-3% of the polyethylene resin mass; the extrusion temperature is 160-180℃; the stretching molding is biaxial stretching controlled at 80-100℃, with longitudinal stretching controlled at 3-5 times and transverse stretching controlled at 4-6 times; and the setting temperature is controlled at 60-70℃ for 5-10 minutes.

[0015] Preferably, in step 2, the matrix resin is polyurethane or polyether ester; the particle size range of the fluorosilane-modified crosslinked PS microspheres is 1-3 μm, and the addition amount is 3-6% of the mass of the two-component modified resin system; the PEG-coated nano-TiO2 is obtained by polyethylene glycol-coated rutile nano-TiO2, and the addition amount is 1-2% of the mass of the two-component modified resin system.

[0016] Preferably, the preparation method of the fluorosilane-modified crosslinked PS microspheres includes step ① mixing 100-110 parts by weight of styrene monomer, 8-10 parts by weight of divinylbenzene, 3-3.5 parts by weight of sodium dodecyl sulfate, and 500-550 parts by weight of deionized water until homogeneous. Under nitrogen protection, the temperature is controlled to rise to 70-72℃, 1.1-1.2 parts by weight of potassium persulfate are added, and the mixture is stirred and reacted for 6-8 hours. After centrifugation and washing, the mixture is dispersed in anhydrous ethanol to obtain a dispersion with a solid content of 20%. Step ② taking 15-16... A mixture of 3-3.2 parts of D3F, 3-3.2 parts of aminopropyltriethoxysilane, and 92-98 parts of toluene was prepared. After adding 0.5-0.55 parts of tetramethylammonium hydroxide, the mixture was refluxed at 80-82℃ for 2 hours to obtain an active fluorosiloxane oligomer toluene solution. In step ③, 200-220 parts of the dispersion were taken and heated to 60℃. The active fluorosiloxane oligomer toluene solution was added dropwise, and the temperature was raised to 80℃ after the addition to react for 4 hours. After centrifugation, washing with acetone, and drying, fluorosilane-modified crosslinked PS microspheres were obtained.

[0017] Preferably, the preparation method of PEG-coated nano-TiO2 includes step ① dispersing 50-55 parts by weight of nano-TiO2 in 500-550 parts by weight of deionized water, dispersing by ultrasonic treatment, adding 5-5.5 parts by weight of tetrabutyl titanate, stirring at 60℃ for 2 hours, and then centrifuging and drying to obtain hydroxylated TiO2; step ② dissolving 30-33 parts by weight of PEG and 8-8.8 parts by weight of β-CD in 200-220 parts by weight of anhydrous ethanol, stirring at 50℃ for 1 hour to obtain an inclusion complex solution; step ③ dispersing hydroxylated TiO2 in 300-330 parts by weight of 1:1 ethanol aqueous solution, adding the inclusion complex solution, adjusting the pH to 5.5, stirring at 45℃ for 6 hours, filtering and drying to obtain PEG-coated nano-TiO2.

[0018] Preferably, in step 3, the coating process is a dry coating process, which includes step ① heating and melting the two-component modified resin system at a temperature of 120-140℃ to obtain a molten coating liquid; step ② using a doctor blade to coat the molten coating liquid onto the surface of the microporous expanded polyethylene film at a coating speed of 5-10 m / min, controlling the coating thickness to be 5-20 μm, to obtain a coated film material; and step ③ sending the coated film material into a drying channel at a temperature of 100-120℃ for drying treatment for 3-5 min to obtain a microporous interconnected composite film material.

[0019] Preferably, in step 3, the coating process is a wet coating process, which includes step ① dissolving the two-component modified resin system in DMF to form a coating liquid, and controlling the mass concentration of the two-component modified resin system to be 15-25%; step ② using a roller to coat the coating liquid onto the surface of the microporous expanded polyethylene original film to form a wet coating film with a thickness of 8-25μm; step ③ immersing the wet coating film in a pure water bath at a temperature of 20-30℃ for 5-10 minutes to obtain a microporous interconnected composite film.

[0020] Preferably, in step 5, the finishing process includes surface finishing and heat setting; the surface finishing is a polyurethane wear-resistant coating or a fluorine-free water-repellent agent; the heat setting temperature is 125-130℃, the setting tension is 20-30 N / m radially and 15-25 N / m weftly, the setting time is 30-60 s, and the radial overfeed rate is controlled at 1-2%.

[0021] Preferably, after 50 washes of the expanded polyethylene waterproof and breathable fabric at room temperature (40℃) according to GB / T 8629-2017, the water pressure resistance is measured to be ≥4250mmH2O and the moisture permeability is measured to be ≥6000 g / (m²). 2 • 24h), tensile strength ≥ 200N and tear strength ≥ 12N.

[0022] As can be seen from the above solutions, this application provides a manufacturing process for polyolefin waterproof and breathable fabrics, which has the following beneficial effects:

[0023] 1. By producing a microporous expanded polyethylene base film with a natural microporous structure, and then using a synergistic coating process, the micropores of the coating layer formed by the two-component modified resin are connected with the micropores of the microporous expanded polyethylene base film, thus constructing an integrated microporous channel. This avoids blocking the air permeability path of the microporous expanded polyethylene base film while enhancing the waterproof barrier through the coating layer.

[0024] 2. By using low surface energy fluorosilane-modified crosslinked PS microspheres to form an oleophobic and hydrophobic interface on the micropore wall of the coating layer, the resistance to water vapor permeation is effectively reduced while blocking liquid water penetration; PEG-coated nano-TiO2 not only ensures the blockage of micropore channels, but also improves the uniformity of the micropore structure of the coating layer, thereby avoiding an imbalance between the air permeability and waterproof performance of the coating layer.

[0025] 3. The fluorosilane-modified crosslinked PS microspheres exhibit superhydrophobic and oleophobic properties on the surface of the coating layer, preventing detergent residue and grease adhesion during water washing. Furthermore, it has the effect of activating the photocatalytic performance of PEG-coated nano-TiO2 under outdoor ultraviolet irradiation, thereby effectively degrading organic pollutants attached to the micropores and preventing pollutants from accumulating and clogging the channels.

[0026] 4. By coating the microporous expanded polyethylene film, the deformation and damage to the micropores caused by the mechanical force impacting the microporous expanded polyethylene film during the water washing process are reduced. In addition, the PEG-coated nano-TiO2 has the effect of buffering the mechanical force generated during water washing, thereby achieving the purpose of ensuring the integrity of the microporous structure. Detailed Implementation

[0027] The technical solutions described below in conjunction with the embodiments of this application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0028] The following is a detailed description of the manufacturing process of a polyolefin waterproof and breathable fabric according to this application.

[0029] A manufacturing process for a polyolefin waterproof and breathable fabric includes the following steps:

[0030] Step 1, Preparation of polyolefin base film: Polyethylene resin is extruded and stretched to obtain microporous expanded polyethylene base film;

[0031] Step 2, Modified Resin Formulation: The polyurethane or polyether ester used as the matrix resin is mixed with functional additives to obtain a two-component modified resin system.

[0032] Step 3, Coating and Molding: The two-component modified resin system is uniformly coated onto at least one surface of the microporous expanded polyethylene original film using a coating process to form a microporous interconnected composite film material.

[0033] Step 4, Post-processing and shaping: The microporous interconnected composite membrane material is dried and cooled to obtain a waterproof and breathable base membrane;

[0034] Step 5, Fabric preparation: The waterproof and breathable base film is compounded with the base fabric, and after finishing, expanded polyethylene waterproof and breathable fabric is obtained.

[0035] The functional additives include fluorosilane-modified crosslinked PS microspheres and PEG-coated nano-TiO2. The fluorosilane-modified crosslinked PS microspheres have a particle size range of 1-3 μm and are added at 3-6% of the mass of the two-component modified resin system. The PEG-coated nano-TiO2 is obtained by coating rutile nano-TiO2 with polyethylene glycol and is added at 1-2% of the mass of the two-component modified resin system.

[0036] It should be noted that the preparation method of fluorosilane-modified crosslinked PS microspheres includes the following steps: Step ① Mix 100-110 parts by weight of styrene monomer, 8-10 parts by weight of divinylbenzene, 3-3.5 parts by weight of sodium dodecyl sulfate, and 500-550 parts by weight of deionized water evenly. Under nitrogen protection, control the temperature to rise to 70-72℃, add 1.1-1.2 parts by weight of potassium persulfate, and stir for 6-8 hours. After centrifugation and washing, disperse in anhydrous ethanol to obtain a dispersion with a solid content of 20%; Step ② Take 15-1 Six parts of D3F, 3-3.2 parts of aminopropyltriethoxysilane, and 92-98 parts of toluene were mixed. After adding 0.5-0.55 parts of tetramethylammonium hydroxide, the mixture was refluxed at 80-82℃ for 2 hours to obtain an active fluorosiloxane oligomer toluene solution. In step ③, 200-220 parts of the dispersion were taken and heated to 60℃. The active fluorosiloxane oligomer toluene solution was added dropwise, and the temperature was raised to 80℃ after the addition to react for 4 hours. After centrifugation, washing with acetone, and drying, fluorosilane-modified crosslinked PS microspheres were obtained.

[0037] The preparation method of PEG-coated nano-TiO2 includes the following steps: Step ① Disperse 50-55 parts by weight of nano-TiO2 in 500-550 parts by weight of deionized water, and after ultrasonic dispersion, add 5-5.5 parts by weight of tetrabutyl titanate, control the temperature at 60℃ and stir for 2 hours, and then centrifuge and dry to obtain hydroxylated TiO2; Step ② Dissolve 30-33 parts by weight of PEG and 8-8.8 parts by weight of β-CD in 200-220 parts by weight of anhydrous ethanol, control the temperature at 50℃ and stir for 1 hour to obtain an inclusion complex solution; Step ③ Disperse hydroxylated TiO2 in 300-330 parts by weight of 1:1 volume ratio of ethanol aqueous solution, add the inclusion complex solution, adjust the pH to 5.5, control the temperature at 45℃ and stir for 6 hours, then filter and dry to obtain PEG-coated nano-TiO2.

[0038] In step 1 of this application embodiment, the microporous expanded polyethylene film is a modified expanded polyethylene film. The modified expanded polyethylene film is obtained by blending polyethylene resin with low surface energy grafted monomers and surface-modified nano-ceramic particles, followed by extrusion and stretching molding.

[0039] The low surface energy grafted monomers are trifluoroethyl methacrylate or vinyltrimethoxysilane, and the addition amount is 2-5% of the polyethylene resin mass. The surface-modified nano-ceramic particles are modified nano-silica that has undergone KH550 surface modification treatment, and the addition amount is 1-3% of the polyethylene resin mass. The extrusion temperature is controlled at 160-180℃, the stretching molding is biaxial stretching controlled at 80-100℃, the longitudinal stretching is controlled at 3-5 times, the transverse stretching is controlled at 4-6 times, and the setting temperature is controlled at 60-70℃ for 5-10 minutes.

[0040] In step 3 of this application embodiment, the coating process is either a dry coating process or a wet coating process. The dry coating process includes step ① heating and melting the two-component modified resin system at a temperature of 120-140℃ to obtain a molten coating liquid; step ② using a doctor blade to coat the molten coating liquid onto the surface of the microporous expanded polyethylene original film at a coating speed of 5-10 m / min, controlling the coating thickness to be 5-20 μm, to obtain a coated film material; step ③ sending the coated film material into a drying channel at a temperature of 100-120℃ for drying treatment for 3-5 min, to obtain a microporous interconnected composite film material. The wet coating process includes step ① dissolving the two-component modified resin system in DMF to form a coating liquid, controlling the mass concentration of the two-component modified resin system to be 15-25%; step ② using a roller to coat the coating liquid onto the surface of the microporous expanded polyethylene original film to form a wet coating membrane material with a thickness of 8-25μm; step ③ immersing the wet coating membrane material in a pure water bath at a temperature of 20-30℃ for 5-10 minutes to obtain a microporous interconnected composite membrane material.

[0041] In step 5 of this application embodiment, the finishing process includes surface finishing and heat setting. Surface finishing is either polyurethane abrasion-resistant coating or fluorine-free water-repellent treatment. The heat setting temperature is 125-130℃, the setting tension is 20-30 N / m radially and 15-25 N / m weftly, the setting time is 30-60 s, and the radial overfeed rate is controlled at 1-2%. The expanded polyethylene waterproof and breathable fabric obtained by the polyolefin waterproof and breathable fabric manufacturing process of this application embodiment, after 50 washes with standard water at 40℃ according to GB / T 8629-2017, shows a water pressure resistance ≥4250 mmH2O and a moisture permeability ≥6000 g / (m²). 2 • 24h), tensile strength ≥ 200N and tear strength ≥ 12N.

[0042] Example 1

[0043] A manufacturing process for a polyolefin waterproof and breathable fabric includes the following steps:

[0044] Step 1, Preparation of polyolefin base film: Polyethylene resin is extruded and stretched to obtain microporous expanded polyethylene base film;

[0045] Step 2, Modified Resin Formulation: The polyurethane or polyether ester used as the matrix resin is mixed with functional additives to obtain a two-component modified resin system.

[0046] Step 3, Coating and Molding: The two-component modified resin system is uniformly coated onto at least one surface of the microporous expanded polyethylene original film using a coating process to form a microporous interconnected composite film material.

[0047] Step 4, Post-processing and shaping: The microporous interconnected composite membrane material is dried and cooled to obtain a waterproof and breathable base membrane;

[0048] Step 5, Fabric preparation: The waterproof and breathable base film is compounded with the base fabric, and after finishing, expanded polyethylene waterproof and breathable fabric is obtained.

[0049] The functional additives include fluorosilane-modified crosslinked PS microspheres and PEG-coated nano-TiO2. The fluorosilane-modified crosslinked PS microspheres have a particle size range of 1-3 μm and are added at 3% of the mass of the two-component modified resin system. The PEG-coated nano-TiO2 is obtained by coating rutile nano-TiO2 with polyethylene glycol and is added at 1% of the mass of the two-component modified resin system.

[0050] It should be noted that the preparation method of fluorosilane-modified crosslinked PS microspheres includes the following steps: Step ① Mix 100 parts by weight of styrene monomer, 8 parts by weight of divinylbenzene, 3 parts by weight of sodium dodecyl sulfate and 500 parts by weight of deionized water evenly, control the temperature to rise to 70°C under nitrogen protection, add 1.1 parts by weight of potassium persulfate and stir for 6 hours, then disperse in anhydrous ethanol after centrifugation and washing to obtain a dispersion with a solid content of 20%; Step ② Mix 15 parts by weight of D3F, 3 parts by weight of aminopropyltriethoxysilane and 92 parts by weight of toluene, add 0.5 parts by weight of tetramethylammonium hydroxide, control the temperature to 80°C and reflux for 2 hours to obtain an active fluorosiloxane oligomer toluene solution; Step ③ Take 200 parts by weight of the dispersion and heat to 60°C, add the active fluorosiloxane oligomer toluene solution dropwise, and after the dropwise addition, heat to 80°C and react for 4 hours, then centrifuge, wash with acetone and dry to obtain fluorosilane-modified crosslinked PS microspheres.

[0051] The preparation method of PEG-coated nano-TiO2 includes the following steps: Step ① Disperse 50 parts by weight of nano-TiO2 in 500 parts by weight of deionized water, and after ultrasonic dispersion, add 5 parts by weight of tetrabutyl titanate, control the temperature at 60℃ and stir for 2 hours, and then centrifuge and dry to obtain hydroxylated TiO2; Step ② Dissolve 30 parts by weight of PEG and 8 parts by weight of β-CD in 200 parts by weight of anhydrous ethanol, control the temperature at 50℃ and stir for 1 hour to obtain an inclusion complex solution; Step ③ Disperse hydroxylated TiO2 in 300 parts by weight of ethanol aqueous solution with a volume ratio of 1:1, then add the inclusion complex solution, adjust the pH to 5.5, control the temperature at 45℃ and stir for 6 hours, then filter and dry to obtain PEG-coated nano-TiO2.

[0052] In step 1 of this application embodiment, the microporous expanded polyethylene film is a modified expanded polyethylene film. The modified expanded polyethylene film is obtained by blending polyethylene resin with low surface energy grafted monomers and surface-modified nano-ceramic particles, followed by extrusion and stretching molding.

[0053] The low surface energy grafted monomers are trifluoroethyl methacrylate or vinyltrimethoxysilane, and the addition amount is 2% of the polyethylene resin mass. The surface-modified nano-ceramic particles are modified nano-silica treated with KH550 surface-modified nano-silica, and the addition amount is 1% of the polyethylene resin mass. The extrusion temperature is controlled at 160℃, the stretching molding is biaxial stretching controlled at 80℃, the longitudinal stretching is controlled at 3 times, the transverse stretching is controlled at 4 times, and the setting temperature is controlled at 60℃ for 5 minutes.

[0054] In step 3 of this application embodiment, the coating process is a dry coating process. The dry coating process includes step ① heating and melting the two-component modified resin system at a temperature of 120°C to obtain a molten coating liquid; step ② using a doctor blade to coat the molten coating liquid onto the surface of the microporous expanded polyethylene film at a coating speed of 5 m / min, controlling the coating thickness to be 5 μm, to obtain a coated film material; step ③ sending the coated film material into a drying channel at a temperature of 100°C for drying treatment for 3 min, to obtain a microporous interconnected composite film material.

[0055] In step 5 of this application embodiment, the finishing process includes surface finishing and heat setting. Surface finishing is either polyurethane abrasion-resistant coating or fluorine-free water-repellent coating. The heat setting temperature is 125°C, the setting tension is 20 N / m radially and 15 N / m weftly, the setting time is 30 s, and the radial overfeed rate is controlled at 1%. The expanded polyethylene waterproof and breathable fabric obtained by the polyolefin waterproof and breathable fabric manufacturing process of this application embodiment, after 50 washes with standard water at 40°C according to GB / T 8629-2017, shows a water pressure resistance ≥4250 mmH2O and a moisture permeability ≥6000 g / (m²). 2 • 24h), tensile strength ≥ 200N and tear strength ≥ 12N.

[0056] Example 2

[0057] A manufacturing process for a polyolefin waterproof and breathable fabric includes the following steps:

[0058] Step 1, Preparation of polyolefin base film: Polyethylene resin is extruded and stretched to obtain microporous expanded polyethylene base film;

[0059] Step 2, Modified Resin Formulation: The polyurethane or polyether ester used as the matrix resin is mixed with functional additives to obtain a two-component modified resin system.

[0060] Step 3, Coating and Molding: The two-component modified resin system is uniformly coated onto at least one surface of the microporous expanded polyethylene original film using a coating process to form a microporous interconnected composite film material.

[0061] Step 4, Post-processing and shaping: The microporous interconnected composite membrane material is dried and cooled to obtain a waterproof and breathable base membrane;

[0062] Step 5, Fabric preparation: The waterproof and breathable base film is compounded with the base fabric, and after finishing, expanded polyethylene waterproof and breathable fabric is obtained.

[0063] The functional additives include fluorosilane-modified crosslinked PS microspheres and PEG-coated nano-TiO2. The fluorosilane-modified crosslinked PS microspheres have a particle size range of 1-3 μm and are added at 4% of the mass of the two-component modified resin system. The PEG-coated nano-TiO2 is obtained by coating rutile nano-TiO2 with polyethylene glycol and is added at 1.5% of the mass of the two-component modified resin system.

[0064] It should be noted that the preparation method of fluorosilane-modified crosslinked PS microspheres includes the following steps: Step ① Mixing 105 parts by weight of styrene monomer, 9 parts by weight of divinylbenzene, 3.2 parts by weight of sodium dodecyl sulfate, and 530 parts by weight of deionized water until homogeneous, raising the temperature to 71°C under nitrogen protection, adding 1.1 parts by weight of potassium persulfate, and stirring for 7 hours, then dispersing the mixture in anhydrous ethanol after centrifugation and washing to obtain a dispersion with a solid content of 20%; Step ② Taking 15.5 parts by weight of D 3.1 parts of aminopropyltriethoxysilane and 94 parts of toluene were mixed, and after adding 0.53 parts of tetramethylammonium hydroxide, the mixture was refluxed at 81°C for 2 hours to obtain an active fluorosiloxane oligomer toluene solution. In step ③, 210 parts of the dispersion were taken and heated to 60°C, and the active fluorosiloxane oligomer toluene solution was added dropwise. After the addition, the temperature was raised to 80°C and reacted for 4 hours. After centrifugation, washing with acetone and drying, fluorosilane-modified crosslinked PS microspheres were obtained.

[0065] The preparation method of PEG-coated nano-TiO2 includes the following steps: Step ① Disperse 53 parts by weight of nano-TiO2 in 530 parts by weight of deionized water, and after ultrasonic dispersion, add 5.2 parts by weight of tetrabutyl titanate, control the temperature at 60℃ and stir for 2 hours, and then centrifuge and dry to obtain hydroxylated TiO2; Step ② Dissolve 32 parts by weight of PEG and 8.5 parts by weight of β-CD in 210 parts by weight of anhydrous ethanol, control the temperature at 50℃ and stir for 1 hour to obtain an inclusion complex solution; Step ③ Disperse hydroxylated TiO2 in 320 parts by weight of ethanol aqueous solution with a volume ratio of 1:1, then add the inclusion complex solution, adjust the pH to 5.5, control the temperature at 45℃ and stir for 6 hours, then filter and dry to obtain PEG-coated nano-TiO2.

[0066] In step 1 of this application embodiment, the microporous expanded polyethylene film is a modified expanded polyethylene film. The modified expanded polyethylene film is obtained by blending polyethylene resin with low surface energy grafted monomers and surface-modified nano-ceramic particles, followed by extrusion and stretching molding.

[0067] The low surface energy grafted monomers are trifluoroethyl methacrylate or vinyltrimethoxysilane, and the addition amount is 3% of the polyethylene resin mass. The surface-modified nano-ceramic particles are modified nano-silica treated with KH550 surface-modified nano-silica, and the addition amount is 2% of the polyethylene resin mass. The extrusion temperature is controlled at 170℃, the stretching molding is biaxial stretching controlled at 90℃, the longitudinal stretching is controlled at 4 times, the transverse stretching is controlled at 5 times, and the setting temperature is controlled at 65℃ for 8 minutes.

[0068] In step 3 of this application embodiment, the coating process is a dry coating process. The dry coating process includes step ① heating and melting the two-component modified resin system at a temperature of 130°C to obtain a molten coating liquid; step ② using a doctor blade to coat the molten coating liquid onto the surface of the microporous expanded polyethylene original film at a coating speed of 8 m / min, controlling the coating thickness to be 12 μm, to obtain a coated film material; step ③ sending the coated film material into a drying channel at a temperature of 110°C for drying treatment for 4 min, to obtain a microporous interconnected composite film material.

[0069] In step 5 of this application embodiment, the finishing process includes surface finishing and heat setting. Surface finishing is either polyurethane abrasion-resistant coating or fluorine-free water-repellent treatment. The heat setting temperature is 128°C, the setting tension is 25 N / m radially and 20 N / m weftly, the setting time is 45 s, and the radial overfeed rate is controlled at 1%. The expanded polyethylene waterproof and breathable fabric obtained by the polyolefin waterproof and breathable fabric manufacturing process of this application embodiment, after 50 washes with standard water at 40°C according to GB / T 8629-2017, shows a water pressure resistance ≥4250 mmH2O and a moisture permeability ≥6000 g / (m²). 2 • 24h), tensile strength ≥ 200N and tear strength ≥ 12N.

[0070] Example 3

[0071] A manufacturing process for a polyolefin waterproof and breathable fabric includes the following steps:

[0072] Step 1, Preparation of polyolefin base film: Polyethylene resin is extruded and stretched to obtain microporous expanded polyethylene base film;

[0073] Step 2, Modified Resin Formulation: The polyurethane or polyether ester used as the matrix resin is mixed with functional additives to obtain a two-component modified resin system.

[0074] Step 3, Coating and Molding: The two-component modified resin system is uniformly coated onto at least one surface of the microporous expanded polyethylene original film using a coating process to form a microporous interconnected composite film material.

[0075] Step 4, Post-processing and shaping: The microporous interconnected composite membrane material is dried and cooled to obtain a waterproof and breathable base membrane;

[0076] Step 5, Fabric preparation: The waterproof and breathable base film is compounded with the base fabric, and after finishing, expanded polyethylene waterproof and breathable fabric is obtained.

[0077] The functional additives include fluorosilane-modified crosslinked PS microspheres and PEG-coated nano-TiO2. The fluorosilane-modified crosslinked PS microspheres have a particle size range of 1-3 μm and are added at 6% of the mass of the two-component modified resin system. The PEG-coated nano-TiO2 is obtained by coating rutile nano-TiO2 with polyethylene glycol and is added at 2% of the mass of the two-component modified resin system.

[0078] It should be noted that the preparation method of fluorosilane-modified crosslinked PS microspheres includes step ① mixing 110 parts by weight of styrene monomer, 10 parts by weight of divinylbenzene, 3.5 parts by weight of sodium dodecyl sulfate, and 550 parts by weight of deionized water until homogeneous. Under nitrogen protection, the temperature is controlled to rise to 72°C, 1.2 parts by weight of potassium persulfate are added, and the mixture is stirred and reacted for 8 hours. After centrifugation and washing, the mixture is dispersed in anhydrous ethanol to obtain a dispersion with a solid content of 20%. Step ② taking 16 parts by weight of D... 3.2 parts of aminopropyltriethoxysilane and 98 parts of toluene were mixed, and after adding 0.55 parts of tetramethylammonium hydroxide, the mixture was refluxed at 82°C for 2 hours to obtain an active fluorosiloxane oligomer toluene solution. In step ③, 220 parts of the dispersion were taken and heated to 60°C. The active fluorosiloxane oligomer toluene solution was added dropwise, and the temperature was raised to 80°C after the addition to react for 4 hours. After centrifugation, washing with acetone and drying, fluorosilane-modified crosslinked PS microspheres were obtained.

[0079] The preparation method of PEG-coated nano-TiO2 includes the following steps: Step ① Disperse 55 parts by weight of nano-TiO2 in 550 parts by weight of deionized water, and after ultrasonic dispersion, add 5.5 parts by weight of tetrabutyl titanate, control the temperature at 60℃ and stir for 2 hours, and then centrifuge and dry to obtain hydroxylated TiO2; Step ② Dissolve 33 parts by weight of PEG and 8.8 parts by weight of β-CD in 220 parts by weight of anhydrous ethanol, control the temperature at 50℃ and stir for 1 hour to obtain an inclusion complex solution; Step ③ Disperse hydroxylated TiO2 in 330 parts by weight of ethanol aqueous solution with a volume ratio of 1:1, then add the inclusion complex solution, adjust the pH to 5.5, control the temperature at 45℃ and stir for 6 hours, then filter and dry to obtain PEG-coated nano-TiO2.

[0080] In step 1 of this application embodiment, the microporous expanded polyethylene film is a modified expanded polyethylene film. The modified expanded polyethylene film is obtained by blending polyethylene resin with low surface energy grafted monomers and surface-modified nano-ceramic particles, followed by extrusion and stretching molding.

[0081] The low surface energy grafted monomers are trifluoroethyl methacrylate or vinyltrimethoxysilane, and the addition amount is 5% of the polyethylene resin mass. The surface-modified nano-ceramic particles are modified nano-silica treated with KH550 surface-modified nano-silica, and the addition amount is 3% of the polyethylene resin mass. The extrusion temperature is controlled at 180℃, the stretching molding is biaxial stretching controlled at 100℃, the longitudinal stretching is controlled at 5 times, the transverse stretching is controlled at 6 times, and the setting temperature is controlled at 70℃ for 10 minutes.

[0082] In step 3 of this embodiment, the coating process is a dry coating process. The dry coating process includes step ① heating and melting the two-component modified resin system at a temperature of 140°C to obtain a molten coating liquid; step ② using a doctor blade to coat the molten coating liquid onto the surface of the microporous expanded polyethylene film at a coating speed of 10 m / min, controlling the coating thickness to be 20 μm, to obtain a coated film material; step ③ sending the coated film material into a drying channel at a temperature of 120°C for drying treatment for 5 min, to obtain a microporous interconnected composite film material.

[0083] In step 5 of this application embodiment, the finishing process includes surface finishing and heat setting. Surface finishing is either polyurethane abrasion-resistant coating or fluorine-free water-repellent treatment. The heat setting temperature is 130℃, the setting tension is 30 N / m radially and 25 N / m weftly, the setting time is 60 s, and the radial overfeed rate is controlled at 2%. The expanded polyethylene waterproof and breathable fabric obtained by the polyolefin waterproof and breathable fabric manufacturing process of this application embodiment, after 50 washes with standard water at 40℃ according to GB / T 8629-2017, shows a water pressure resistance ≥4250 mmH2O and a moisture permeability ≥6000 g / (m²). 2 • 24h), tensile strength ≥ 200N and tear strength ≥ 12N.

[0084] Example 4

[0085] The difference between Example 4 and Example 2 is that the coating process in Example 4 is a wet coating process. The wet coating process includes step ① dissolving the two-component modified resin system in DMF to form a coating liquid, controlling the mass concentration of the two-component modified resin system to be 15%; step ② using a roller to apply the coating liquid to the surface of the microporous expanded polyethylene original film to form a wet coating film material with a thickness of 8μm; step ③ immersing the wet coating film material in a pure water bath at a temperature of 20℃ for 5 minutes to obtain a microporous interconnected composite film material.

[0086] Example 5

[0087] The difference between Example 5 and Example 2 is that the coating process in Example 5 is a wet coating process. The wet coating process includes step ① dissolving the two-component modified resin system in DMF to form a coating liquid, controlling the mass concentration of the two-component modified resin system to be 20%; step ② using a roller to apply the coating liquid to the surface of the microporous expanded polyethylene original film to form a wet coating film material with a thickness of 15μm; step ③ immersing the wet coating film material in a pure water bath at a temperature of 25℃ for 8 minutes to obtain a microporous interconnected composite film material.

[0088] Example 6

[0089] The difference between Example 6 and Example 2 is that the coating process in Example 6 is a wet coating process. The wet coating process includes step ① dissolving the two-component modified resin system in DMF to form a coating liquid, controlling the mass concentration of the two-component modified resin system to be 25%; step ② using a roller to apply the coating liquid to the surface of the microporous expanded polyethylene original film to form a wet coating film material with a thickness of 25μm; step ③ immersing the wet coating film material in a pure water bath at a temperature of 30℃ for 10 minutes to obtain a microporous interconnected composite film material.

[0090] Comparative Example 1

[0091] The difference between Comparative Example 1 and Example 2 is that PS microspheres were used in Comparative Example 1 instead of fluorosilane-modified crosslinked PS microspheres.

[0092] Comparative Example 2

[0093] The difference between Comparative Example 2 and Example 2 is that in Comparative Example 2, nano-TiO2 is used instead of PEG-coated nano-TiO2.

[0094] Comparative Example 3

[0095] The difference between Comparative Example 3 and Example 2 is that the modified expanded polyethylene film in Comparative Example 3 did not contain low surface energy grafted monomers.

[0096] Performance testing:

[0097] 1. Water pressure resistance: The test was conducted according to GB / T 4744-2013 "Determination of water resistance of textiles - hydrostatic pressure method";

[0098] 2. Moisture permeability: According to GB / T 12704.2-2009 "Textiles - Test methods for moisture permeability of fabrics - Part 2: Evaporation method"

[0099] 3. Washing treatment: The experiment was conducted in accordance with GB / T 8629-2017 "Domestic washing and drying procedures for testing textiles".

[0100] The performance test results are shown in Table 1 below.

[0101] Table 1 Performance Test Results

[0102] <![CDATA[Hydrostatic pressure resistance before washing (mmH2O)]]> <![CDATA[Water vapor transmission rate (g / m 2 ·24 h)]]> <![CDATA[Water vapor transmission rate after washing (g / m 2 ·24h)]]> <![CDATA[Water pressure resistance after washing (mmH2O)]]> Example 1 13200 6230 6580 4500 Example 2 13450 7000 7520 4750 Example 3 13700 7750 7850 5050 Example 4 13250 7250 7526 4550 Example 5 13450 7560 7850 4600 Example 6 13550 8000 8520 4850 Comparative Example 1 9750 2530 2830 3600 Comparative Example 2 10000 3210 3520 3850 Comparative Example 3 9800 3050 3220 3700

[0103] As shown in Table 1 above, in this embodiment, the use of fluorosilane-modified cross-linked PS microspheres effectively enhances the hydrophobicity of the expanded polyethylene waterproof and breathable fabric. This ensures that the particle size of the fluorosilane-modified cross-linked PS microspheres matches the micropores of the modified expanded polyethylene film, reducing moisture permeability resistance based on the formed microporous interconnected structure. Furthermore, as the addition amount increases from 3% to 6%, it enhances both hydrophobicity and the integrity of the porous structure, effectively improving water pressure resistance and synergistically reducing micropore permeability. Simultaneously, the synergistic effect of PEG-coated nano-TiO2 effectively enhances the mechanical properties of the expanded polyethylene waterproof and breathable fabric. Moreover, the improved dispersibility of the coated nano-TiO2 prevents agglomeration and blockage of the micropores.

[0104] In wet coating and dry coating, the micropore size is determined by the phase separation rate between DMF and water in wet coating. Therefore, with increases in coating solution concentration, coating thickness, and solidification temperature, phase separation is more complete, resulting in denser and more interconnected micropores. Consequently, the water pressure resistance and moisture permeability of Examples 4-6 gradually approach or even partially exceed those of Example 2. Meanwhile, the interfacial bonding between the wet-coated coating and the modified expanded polyethylene film is more complete under molten conditions than with dry coating. Therefore, based on the same parameters, the tensile strength of wet coating will be lower than that of dry coating.

[0105] Compared to Comparative Examples 1 to 3 and Example 2, the unmodified PS microspheres lack fluorosilane groups on their surface, exhibiting poor hydrophobicity and insufficient compatibility with the modified resin. This leads to agglomeration in the coating, resulting in decreased water pressure resistance, increased moisture permeability, and reduced mechanical properties. Furthermore, the poor dispersibility of uncoated nano-TiO2 prevents it from improving moisture permeability and poses a risk of clogging micropores. Agglomeration of nano-TiO2 also leads to internal stress concentration, further degrading mechanical properties. Simultaneously, given the high surface energy of the ePE film, it readily adsorbs water molecules, causing micropore wetting and clogging. Therefore, without the addition of low surface energy grafted monomers, the interfacial compatibility between the coating and the ePE film decreases, further weakening the adhesion and reducing mechanical properties and water pressure resistance.

[0106] In summary, this application provides a manufacturing process for a polyolefin waterproof and breathable fabric. This process involves creating a microporous expanded polyethylene (PE) base film with a natural microporous structure, followed by a synergistic coating process. This allows the micropores of the coating layer formed by the two-component modified resin to connect with the micropores of the PE base film, constructing an integrated microporous channel. This avoids clogging the breathable pathways of the PE base film while enhancing the waterproof barrier through the coating layer. Based on low surface energy fluorosilane-modified cross-linked PS microspheres, an oleophobic and hydrophobic interface is formed on the micropore walls of the coating layer, effectively reducing water vapor permeation resistance while blocking liquid water penetration. PEG-coated nano-TiO2, while ensuring the blockage of microporous channels, also improves the uniformity of the microporous structure of the coating layer, thereby preventing an imbalance between the breathability and waterproof performance of the coating layer. The fluorosilane-modified crosslinked PS microspheres possess fluorosilane groups on their surface, resulting in a superhydrophobic and oleophobic microporous surface in the coating layer. This prevents detergent residue and grease adhesion during washing. Furthermore, outdoor ultraviolet irradiation activates the photocatalytic properties of PEG-coated nano-TiO2, effectively degrading organic pollutants adhering to the micropores and preventing their accumulation and blockage. After coating, the microporous expanded polyethylene membrane effectively reduces micropore deformation and damage caused by mechanical forces during washing. The PEG-coated nano-TiO2 also buffers the mechanical forces generated during washing, thus ensuring the integrity of the microporous structure.

[0107] The terms “first,” “second,” “third,” “fourth,” etc., used in this application (if applicable) are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, or apparatus that includes a series of steps or units is not necessarily limited to those explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, or apparatus.

[0108] It should be noted that the use of terms such as "first" and "second" in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of those features. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed in this application.

[0109] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A manufacturing process for a polyolefin waterproof and breathable fabric, characterized in that, Includes the following steps: Step 1, Preparation of polyolefin base film: Polyethylene resin is extruded and stretched to obtain microporous expanded polyethylene base film; Step 2, Modified Resin Formulation: Mix the base resin with functional additives to obtain a two-component modified resin system; Step 3, Coating and Molding: The two-component modified resin system is uniformly coated onto at least one surface of the microporous expanded polyethylene original film using a coating process to form a microporous interconnected composite film material. Step 4, Post-processing and shaping: The microporous interconnected composite membrane material is dried and cooled to obtain a waterproof and breathable base membrane; Step 5, Fabric preparation: The waterproof and breathable base film is compounded with the base fabric, and after finishing, expanded polyethylene waterproof and breathable fabric is obtained. The functional additives include fluorosilane-modified crosslinked PS microspheres and PEG-coated nano-TiO2.

2. The manufacturing process of a polyolefin waterproof and breathable fabric according to claim 1, characterized in that: In step 1, the microporous expanded polyethylene film is a modified expanded polyethylene film, which is obtained by blending polyethylene resin with low surface energy grafted monomers and surface modified nano-ceramic particles, and then extruding and stretching them sequentially.

3. The manufacturing process of a polyolefin waterproof and breathable fabric according to claim 2, characterized in that: The low surface energy grafted monomer is trifluoroethyl methacrylate or vinyltrimethoxysilane, and the addition amount is 2-5% of the polyethylene resin mass. The surface-modified nano-ceramic particles are modified nano-silica treated with KH550 surface modification, and the addition amount is 1-3% of the polyethylene resin mass. The extrusion temperature is 160-180℃, the stretching molding is biaxial stretching controlled at 80-100℃, the longitudinal stretching is controlled at 3-5 times, the transverse stretching is controlled at 4-6 times, and the setting temperature is controlled at 60-70℃ for 5-10 minutes.

4. The manufacturing process of a polyolefin waterproof and breathable fabric according to claim 1, characterized in that: In step 2, the matrix resin is polyurethane or polyether ester; the particle size range of the fluorosilane-modified crosslinked PS microspheres is 1-3 μm, and the addition amount is 3-6% of the mass of the two-component modified resin system; the PEG-coated nano TiO2 is obtained by polyethylene glycol-coated rutile phase nano TiO2, and the addition amount is 1-2% of the mass of the two-component modified resin system.

5. The manufacturing process of a polyolefin waterproof and breathable fabric according to claim 4, characterized in that: The preparation method of the fluorosilane-modified crosslinked PS microspheres includes step ① mixing 100-110 parts by weight of styrene monomer, 8-10 parts by weight of divinylbenzene, 3-3.5 parts by weight of sodium dodecyl sulfate, and 500-550 parts by weight of deionized water until homogeneous. Under nitrogen protection, the temperature is controlled to rise to 70-72℃, 1.1-1.2 parts by weight of potassium persulfate are added, and the mixture is stirred and reacted for 6-8 hours. After centrifugation and washing, the mixture is dispersed in anhydrous ethanol to obtain a dispersion with a solid content of 20%. Step ② taking 15-16 parts by weight of... D3F, 3-3.2 parts of aminopropyltriethoxysilane, and 92-98 parts of toluene were mixed. After adding 0.5-0.55 parts of tetramethylammonium hydroxide, the mixture was refluxed at 80-82℃ for 2 hours to obtain an active fluorosiloxane oligomer toluene solution. In step ③, 200-220 parts of the dispersion were taken and heated to 60℃. The active fluorosiloxane oligomer toluene solution was added dropwise, and the temperature was raised to 80℃ after the addition to react for 4 hours. After centrifugation, washing with acetone, and drying, fluorosilane-modified crosslinked PS microspheres were obtained.

6. The manufacturing process of a polyolefin waterproof and breathable fabric according to claim 4, characterized in that: The preparation method of PEG-coated nano-TiO2 includes the following steps: Step ① Dispersing 50-55 parts by weight of nano-TiO2 in 500-550 parts by weight of deionized water, dispersing by ultrasonic treatment, adding 5-5.5 parts by weight of tetrabutyl titanate, stirring at 60℃ for 2 hours, and then centrifuging and drying to obtain hydroxylated TiO2; Step ② Dissolving 30-33 parts by weight of PEG and 8-8.8 parts by weight of β-CD in 200-220 parts by weight of anhydrous ethanol, stirring at 50℃ for 1 hour to obtain an inclusion complex solution; Step ③ Dispersing hydroxylated TiO2 in 300-330 parts by weight of 1:1 ethanol aqueous solution, adding the inclusion complex solution, adjusting the pH to 5.5, stirring at 45℃ for 6 hours, filtering and drying to obtain PEG-coated nano-TiO2.

7. The manufacturing process of a polyolefin waterproof and breathable fabric according to claim 1, characterized in that: In step 3, the coating process is a dry coating process, which includes step ① heating and melting the two-component modified resin system at a temperature of 120-140℃ to obtain a molten coating liquid; step ② using a doctor blade to coat the molten coating liquid onto the surface of the microporous expanded polyethylene film at a coating speed of 5-10 m / min, controlling the coating thickness to be 5-20 μm, to obtain a coated film material; and step ③ sending the coated film material into a drying channel at a temperature of 100-120℃ for drying treatment for 3-5 min to obtain a microporous interconnected composite film material.

8. The manufacturing process of a polyolefin waterproof and breathable fabric according to claim 1, characterized in that: In step 3, the coating process is a wet coating process, which includes step ① dissolving the two-component modified resin system in DMF to form a coating liquid, and controlling the mass concentration of the two-component modified resin system to be 15-25%; step ② using a roller to apply the coating liquid to the surface of the microporous expanded polyethylene film to form a wet coating film with a thickness of 8-25μm; step ③ immersing the wet coating film in a pure water bath at a temperature of 20-30℃ for 5-10 minutes to obtain a microporous interconnected composite film.

9. The manufacturing process of a polyolefin waterproof and breathable fabric according to claim 1, characterized in that: In step 5, the finishing process includes surface finishing and heat setting; the surface finishing is either polyurethane wear-resistant coating or fluorine-free water-repellent coating; the heat setting temperature is 125-130℃, the setting tension is 20-30 N / m radially and 15-25 N / m weftly, the setting time is 30-60 s, and the radial overfeed rate is controlled at 1-2%.

10. The manufacturing process of a polyolefin waterproof and breathable fabric according to claim 1, characterized in that: After 50 washes of the expanded polyethylene waterproof and breathable fabric at room temperature (40℃) according to GB / T 8629-2017 standard, the water pressure resistance was measured to be ≥4250mmH2O and the moisture permeability was measured to be ≥6000g / (m²). 2 • 24h), tensile strength ≥ 200N and tear strength ≥ 12N.