A polyethylene flash nonwoven fabric

Abstract

This invention relates to a polyethylene flash nonwoven fabric, characterized by a wet tensile strength of 1600–2400 N / m, a wet tensile strength retention rate of 0.55–0.70, an opacity of 0.85–0.95, and a basis weight of 35–45 g / m². 2 The wet-soaking process conditions for the samples were as follows: first, the water temperature for wet-soaking was 40℃, and the soaking time was 8 hours; second, the temperature was raised to 60℃, and the soaking time was 8 hours. This application exhibits good wet tensile strength and wet tensile strength retention rate, and has wide applications.

Description

[Technical Field]

[0001] This invention relates to the field of textile production technology, specifically to a polyethylene flash nonwoven fabric. [Background Technology]

[0002] Flash spinning was first proposed by scientists Herbert Blades, James Rushton White, and Chadds Ford at DuPont Research Laboratories. They filed the first US patent application, US3081519, on flash spinning in 1962, which was granted in March 1963. DuPont then registered the trademark "Tyvek" for the product in 1965 and officially began commercial sales under this brand in 1967. Subsequently, a large number of DuPont scientists continuously improved the process and technology over the next 30 years, ensuring DuPont maintained a monopoly on this technology. In particular, US3081519, as a cited patent, has been cited 267 times, demonstrating its status as a fundamental core patent.

[0003] Flash spinning involves dissolving a polymer in a solvent to create a spinning solution, which is then extruded through a spinneret. Due to the rapid evaporation of the solvent, the polymer is re-solidified into fibers. These fibers are adsorbed onto a web forming curtain to directly form a web, which is then hot-pressed by hot rollers to obtain a flash nonwoven fabric.

[0004] Chinese Patent Publication No. CN111389288A discloses a method and apparatus for dissolving polymers in a solvent. The specific technical solution is a method for dissolving polymers in a solvent, comprising two stages in series: The first stage provides shear-force stirring to the heterogeneous mixture of polymer and solvent, breaking down and dispersing the polymer in the dissolution process; the second stage ensures that the broken polymer and solvent are mixed uniformly. The technical effect is that after the molten polymer and solvent are mixed, they are initially in a heterogeneous state where they are not yet fully dissolved. Due to the high viscosity of the molten polymer, forced dispersion is necessary to quickly disperse the molten polymer into small droplets, increasing the surface area in contact with the solvent and achieving rapid dissolution. The two-stage series dissolution process and apparatus are used to dissolve and mix the heterogeneous system. The first stage uses a high-shear-force stirring device to quickly break down molten polymer clumps and disperse the molten polymer into small droplets, geometrically increasing the liquid-liquid contact surface, thereby rapidly dissolving the molten polymer into the solvent. The second stage uses a device with convective mixing effect, which makes the solution more uniform, thus maintaining a uniform and stable concentration in the output, which is beneficial for stable spinning. The method and equipment of this technology can reduce the average liquid holding time to 25 minutes. This technology is mainly applied to the field of flash spinning equipment, but its effect on improving the performance of flash-spun products has not been reported.

[0005] Chinese Patent Publication No. CN113355755A relates to polymer sheets prepared by flash evaporation. The polymer sheet prepared by flash evaporation is characterized in that the raw material of the polymer sheet includes polyethylene. In the average bending length of the polymer sheet in two directions, the larger is a first average bending length CV, and the smaller is a second average bending length MV. The CV is 5.8–8.2 cm, and the CV / MV ratio is 1.05–3. This technology mainly improves the bending performance of flash-evaporated products and does not involve improving the wet tensile strength performance as described in this application.

[0006] Chinese Patent Publication No. CN113262605A relates to a polyethylene sheet material, the main raw material of which is polyethylene particles. The basis weight of the polyethylene sheet material is above 40 g / m², and the BET specific area is above 9 m² / gm². The mass fraction of polyethylene particles in the polyethylene sheet material is above 80%. The raw material also includes one or more of polyethylene homologues, polypropylene, polyolefins, polybutene-1, poly(4-methyl-1-pentene), and polyvinylidene fluoride. This application has good performance and a wide range of applications. This technology mainly solves the technical problem of solvent reuse during flash evaporation and does not involve the improvement of tensile strength performance of this application.

[0007] This application addresses the issue that traditional flash-spun nonwoven fabrics exhibit a significant decrease in wet tensile strength in the humid rainy season of southern regions. This application improves the wet tensile strength by modifying the spinning raw materials and processes, thereby extending its service life and expanding its application range. [Summary of the Invention]

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide a polyethylene flash nonwoven fabric.

[0009] The objective of this invention is achieved through the following technical solution:

[0010] A polyethylene flash nonwoven fabric, the raw material of which includes polyethylene, has a wet tensile strength of 1600-2400 N / m, a wet tensile strength retention rate of 0.55-0.70, and an opacity of 0.85-0.95;

[0011] Under standard atmospheric conditions, the tensile strength of the same specimen after wetting was determined. The wetting process conditions were as follows: the initial wetting temperature was 40℃, and the wetting time was 8 hours; then the temperature was increased to 60℃, and the wetting time was 8 hours. During the test, the constant tensile rate was 50 mm / min, and the relative humidity of the environment was 48–52% RH.

[0012] The wettation process for the samples in this application uses a water temperature of 40°C for 8 hours; then the temperature is raised to 60°C and the samples are wetted for another 8 hours. The test conditions in this application are different from conventional test conditions (national standard test) and are relatively harsh. We designed a cyclic wettation process, mainly considering the wet tensile strength of the product at different temperatures, to simulate the actual use environment of the product, to examine the service life of the product, and then to improve the design of raw materials and processes to ultimately improve the performance of the product.

[0013] The wet tensile strength of the polyethylene flash nonwoven fabric is 1600-1800 N / m.

[0014] The wet tensile strength of the polyethylene flash nonwoven fabric is 1800-2000 N / m.

[0015] The wet tensile strength of the polyethylene flash nonwoven fabric is 2000-2200 N / m.

[0016] The wet tensile strength of the polyethylene flash nonwoven fabric is 2200-2400 N / m.

[0017] The wet tensile strength retention rate of the polyethylene flash nonwoven fabric is 0.55-0.60.

[0018] The wet tensile strength retention rate of the polyethylene flash nonwoven fabric is 0.60 to 0.65.

[0019] The wet tensile strength retention rate of the polyethylene flash nonwoven fabric is 0.65-0.70.

[0020] The opacity of the polyethylene flash nonwoven fabric is 0.85 to 0.88.

[0021] The opacity of the polyethylene flash nonwoven fabric is 0.88 to 0.92.

[0022] The opacity of the polyethylene flash nonwoven fabric is 0.92 to 0.95.

[0023] The D65 fluorescence brightness of the aforementioned polyethylene flash nonwoven fabric is 0.85 to 0.95.

[0024] The basis weight of the polyethylene flash nonwoven fabric is 35-85 g / m². 2 The preferred concentration is 38–45 g / m³. 2 .

[0025] The main influencing factors on polyethylene flash nonwoven fabric are the spinning raw materials (polymer and spinning solvent), spinning process (spinning temperature and spinning pressure), and post-treatment hot-pressing process. This application mainly focuses on controlling the manufacturing method of polyethylene flash nonwoven fabric by adjusting the spinning raw materials, spinning temperature, and hot-pressing temperature.

[0026] A polyethylene flash nonwoven fabric, the raw material of which is a modified polyethylene and ethylene-1-octene block copolymer.

[0027] The mass fraction of the ethylene-1-octene block copolymer modifier in the mixture of polyethylene and the ethylene-1-octene block copolymer modifier is 4-8%.

[0028] The modified ethylene-1-octene block copolymer is a composite bilayer material in which a layer of zinc barium white is adsorbed on the surface of the ethylene-1-octene block copolymer.

[0029] A method for manufacturing polyethylene flash nonwoven fabric, comprising the following technical steps:

[0030] I. Preparation of spinning solution

[0031] The spinning solution contains polyethylene, an ethylene-1-octene block copolymer modifier, and a spinning solvent.

[0032] The mass fraction of polyethylene in the spinning solution is 13-17%.

[0033] The mass fraction of the ethylene-1-octene block copolymer modifier in the mixture of polyethylene and the ethylene-1-octene block copolymer modifier is 4-8%.

[0034] The modified ethylene-1-octene block copolymer is a composite bilayer material in which a layer of zinc barium white is adsorbed on the surface of the ethylene-1-octene block copolymer.

[0035] The spinning solvent is one or more of the following: trichlorofluoromethane, 1,1-dichloro-2,2,2-trifluoroethane, 1,2-dichloro-1,2,2-trifluoroethane, 1,1-dichloro-2,2-difluoroethane, 1,2-dichloro-1,1-difluoroethane and 1,1-dichloro-1-fluoroethane, 1,1,1,2-tetrafluoroethane (HC-134a), 1,1-difluoroethane (HC-152a), 1,1,1,3,3-pentafluoropropane, 1,1,2,2,3,3,4,4-octafluorobutane, 1,1,1,3,3-pentafluorobutane, 2,3-dihydrodecafluoropentane, 1H,6H-perfluorohexane, 1H-perfluoroheptane, and 1H-perfluorohexane; or its isomers or analogs.

[0036] The spinning solvent is 1,1,1,3,3-pentafluorobutane and 1H-perfluoroheptane, with a volume ratio of 2:1.

[0037] The preparation method of the modified ethylene-1-octene block copolymer is as follows: (1) Disperse the ethylene-1-octene block copolymer powder in concentrated sulfuric acid and heat treat it at 100-110℃ for 15-45 min, then filter and dry it to obtain the modified ethylene-1-octene block copolymer; (2) Disperse the modified ethylene-1-octene block copolymer in zinc sulfate solution, add it to barium chloride solution by microwave stirring to obtain a precipitate, which is a composite bilayer material with a layer of zinc barium white adsorbed on the surface of the ethylene-1-octene block copolymer.

[0038] The mass ratio of ethylene-1-octene block copolymer powder to zinc sulfate solution is 1:0.12 to 1:0.16.

[0039] The molar ratio of zinc sulfate in zinc sulfate solution to barium sulfide in barium sulfide solution is 1:1.05 to 1:1.25.

[0040] In the presence of concentrated sulfuric acid, the surface of ethylene-1-octene block copolymer (E-1-octene) microparticles undergoes sulfonation, forming sulfonic acid groups. The sulfonated E-1-octene block copolymer powder can then form barium sulfate and zinc sulfide with zinc and barium ions, achieving fixation through chelation by the sulfonic acid groups of the E-1-octene block copolymer, resulting in barium sulfate and zinc sulfide precipitates on the surface (a more effective method than physical mixing). Simultaneously, the E-1-octene block copolymer contains vinyl group fragments, exhibiting good compatibility with polyethylene, resulting in better uniform dispersion in polyethylene spinning solutions, increased flowability, and improved mechanical properties. The addition of the E-1-octene block copolymer-encapsulated zinc-barium white complex disrupts the flash fiber bundles during flash spinning, allowing the complex to penetrate between the fiber bundles. Furthermore, due to the excellent elastic recovery and stress relaxation properties of the E-1-octene block copolymer itself, the wet tensile strength of the flash nonwoven fabric under stress can be improved. Secondly, because the molecular chains of the ethylene-1-octene block copolymer in the modified ethylene-1-octene block copolymer consist of nonpolar saturated single bonds and lack polar groups, and due to the presence of zinc barium white components, it prevents yellowing due to aging and increases whiteness, water vapor resistance, aging resistance, and corrosion resistance, thereby ultimately extending its service life. Finally, the addition of the compound increases the opacity of the fabric, thereby increasing the surface ink absorption of the product and improving the printability of the nonwoven fabric.

[0041] II. Flash spinning

[0042] Then, flash spinning is performed at a temperature of 200–215℃ to obtain flash fibers. These fibers are then hot-pressed by rollers at a temperature of 115–125℃ and a linear pressure of 7–15 N / m to obtain polyethylene flash nonwoven fabric.

[0043] Compared with the prior art, the positive effects of the present invention are:

[0044] This application mainly controls the spinning raw materials, spinning temperature, and hot pressing temperature to obtain polyethylene flash nonwoven fabric with better performance, which has good wet tensile strength, opacity, and brightness.

Detailed Implementation Methods

[0045] The following provides a specific embodiment of a polyethylene flash nonwoven fabric according to the present invention.

[0046] Example 1

[0047] A method for manufacturing polyethylene flash nonwoven fabric, comprising the following technical steps:

[0048] I. Preparation of spinning solution

[0049] The spinning solution contains polyethylene, an ethylene-1-octene block copolymer modifier, and a spinning solvent.

[0050] The mass fraction of polyethylene in the spinning solution is 13%.

[0051] The mass fraction of the ethylene-1-octene block copolymer modifier in the mixture of polyethylene and the ethylene-1-octene block copolymer modifier is 4%.

[0052] The modified ethylene-1-octene block copolymer is a composite bilayer material in which a layer of zinc barium white is adsorbed on the surface of the ethylene-1-octene block copolymer.

[0053] The spinning solvent is 1,1,1,3,3-pentafluorobutane and 1H-perfluoroheptane, with a volume ratio of 2:1.

[0054] The preparation method of the modified ethylene-1-octene block copolymer is as follows: (1) Disperse the ethylene-1-octene block copolymer powder in concentrated sulfuric acid and heat treat it at 100-110℃ for 15-45 min, then filter and dry it to obtain the modified ethylene-1-octene block copolymer; (2) Disperse the modified ethylene-1-octene block copolymer in zinc sulfate solution, add it to barium chloride solution by microwave stirring to obtain a precipitate, which is a composite bilayer material with a layer of zinc barium white adsorbed on the surface of the ethylene-1-octene block copolymer.

[0055] The mass ratio of ethylene-1-octene block copolymer powder to zinc sulfate solution was 1:0.12.

[0056] The molar ratio of zinc sulfate in zinc sulfate solution to barium sulfide in barium sulfide solution is 1:1.05.

[0057] In the presence of concentrated sulfuric acid, the surface of ethylene-1-octene block copolymer (E-1-octene) microparticles undergoes sulfonation, forming sulfonic acid groups. The sulfonated E-1-octene block copolymer powder can then form barium sulfate and zinc sulfide with zinc and barium ions, achieving fixation through chelation by the sulfonic acid groups of the E-1-octene block copolymer, resulting in barium sulfate and zinc sulfide precipitates on the surface (a more effective method than physical mixing). Simultaneously, the E-1-octene block copolymer contains vinyl group fragments, exhibiting good compatibility with polyethylene, resulting in better uniform dispersion in polyethylene spinning solutions, increased flowability, and improved mechanical properties. The addition of the E-1-octene block copolymer-encapsulated zinc-barium white complex disrupts the flash fiber bundles during flash spinning, allowing the complex to penetrate between the fiber bundles. Furthermore, due to the excellent elastic recovery and stress relaxation properties of the E-1-octene block copolymer itself, the wet tensile strength of the flash nonwoven fabric under stress can be improved. Secondly, because the molecular chains of the ethylene-1-octene block copolymer in the modified ethylene-1-octene block copolymer consist of nonpolar saturated single bonds and lack polar groups, and due to the presence of zinc barium white components, it prevents yellowing due to aging and increases whiteness, water vapor resistance, aging resistance, and corrosion resistance, thereby ultimately extending its service life. Finally, the addition of the compound increases the opacity of the fabric, thereby increasing the surface ink absorption of the product and improving the printability of the nonwoven fabric.

[0058] II. Flash spinning

[0059] The fibers were then subjected to flash spinning at a temperature of 200℃ to obtain flash fibers, which were then hot-pressed onto rollers at a temperature of 115℃ and a linear pressure of 7 N / m to obtain polyethylene flash nonwoven fabric. The performance of the polyethylene flash nonwoven fabric was tested, and the specific data are shown in Table 1.

[0060] Performance testing methods:

[0061] (a) Wet tensile strength: The maximum tensile strength that a wet sample per unit width can withstand before breaking when it is immersed in distilled or deionized water, i.e., the ratio of the maximum tensile strength to the width, is expressed in N / m.

[0062] The wet tensile strength retention rate is the ratio of the tensile strength of the same specimen before and after wetting to the tensile strength before wetting, measured under standard atmospheric conditions. The tensile strength of the same specimen after wetting was measured under standard atmospheric conditions. The wetting process conditions were as follows: first, the water temperature was 40℃, and the wetting time was 8 hours; then the temperature was increased to 60℃, and the wetting time was 8 hours. During the test, the constant tensile rate was 50 mm / min, and the relative humidity of the environment was 48–52% RH.

[0063] For the tensile strength test, please refer to the national standard GB / T 24328.4-2009. Take 10 samples, of which 5 transverse samples are used for testing to obtain values ​​and 5 longitudinal samples are used for testing to obtain values. Then, calculate the average value to obtain the wet tensile strength of the sample. It will not be described in detail here.

[0064] (II) Opacity: Refer to the national standard GB / T1543-2005, Determination of Opacity (Paper Backing) of Paper and Paperboard (Diffuse Reflectance Method). Test Principle: According to GB / T7973, the single-layer emissivity of the backing tube and the internal emissivity of the sample are measured, and the ratio of these two values ​​is used to obtain the opacity. The testing instrument is an emissivity spectrophotometer. Ten samples are taken to test the opacity of the front and back sides of the sample, and then the values ​​of the front and back sides are averaged to obtain the opacity of the sample.

[0065] (III) D65 Fluorescence Brightness: For specific testing details, refer to GB / T 7974-2013 Determination of Blue Light Diffuse Reflectance Factor D65 Brightness in Paper, Paperboard and Pulp. The test should be conducted according to the method used for paper and paperboard. Take 10 samples, testing the brightness of the front side of 5 samples and the brightness of the back side of the other 5 samples. Then calculate the average to obtain the D65 fluorescence brightness F of the sample. D65 refers to the fluorescence excited by a D65 light source, approximately ISO 2470-1.

[0066] Example 2

[0067] A method for manufacturing polyethylene flash nonwoven fabric, comprising the following technical steps:

[0068] I. Preparation of spinning solution

[0069] The spinning solution contains polyethylene, an ethylene-1-octene block copolymer modifier, and a spinning solvent.

[0070] The mass fraction of polyethylene in the spinning solution is 13.5%.

[0071] The mass fraction of the ethylene-1-octene block copolymer modifier in the mixture of polyethylene and the ethylene-1-octene block copolymer modifier is 6%.

[0072] The modified ethylene-1-octene block copolymer is a composite bilayer material in which a layer of zinc barium white is adsorbed on the surface of the ethylene-1-octene block copolymer.

[0073] The spinning solvent is 1,1,1,3,3-pentafluorobutane and 1H-perfluoroheptane, with a volume ratio of 2:1.

[0074] The preparation method of the modified ethylene-1-octene block copolymer is as follows: (1) Disperse the ethylene-1-octene block copolymer powder in concentrated sulfuric acid and heat treat it at 100-110℃ for 15-45 min, then filter and dry it to obtain the modified ethylene-1-octene block copolymer; (2) Disperse the modified ethylene-1-octene block copolymer in zinc sulfate solution, add it to barium chloride solution by microwave stirring to obtain a precipitate, which is a composite bilayer material with a layer of zinc barium white adsorbed on the surface of the ethylene-1-octene block copolymer.

[0075] The mass ratio of ethylene-1-octene block copolymer powder to zinc sulfate solution was 1:0.14.

[0076] The molar ratio of zinc sulfate in zinc sulfate solution to barium sulfide in barium sulfide solution is 1:1.15.

[0077] In the presence of concentrated sulfuric acid, the surface of ethylene-1-octene block copolymer (E-1-octene) microparticles undergoes sulfonation, forming sulfonic acid groups. The sulfonated E-1-octene block copolymer powder can then form barium sulfate and zinc sulfide with zinc and barium ions, achieving fixation through chelation by the sulfonic acid groups of the E-1-octene block copolymer, resulting in barium sulfate and zinc sulfide precipitates on the surface (a more effective method than physical mixing). Simultaneously, the E-1-octene block copolymer contains vinyl group fragments, exhibiting good compatibility with polyethylene, resulting in better uniform dispersion in polyethylene spinning solutions, increased flowability, and improved mechanical properties. The addition of the E-1-octene block copolymer-encapsulated zinc-barium white complex disrupts the flash fiber bundles during flash spinning, allowing the complex to penetrate between the fiber bundles. Furthermore, due to the excellent elastic recovery and stress relaxation properties of the E-1-octene block copolymer itself, the wet tensile strength of the flash nonwoven fabric under stress can be improved. Secondly, because the molecular chains of the ethylene-1-octene block copolymer in the modified ethylene-1-octene block copolymer consist of nonpolar saturated single bonds and lack polar groups, and due to the presence of zinc barium white components, it prevents yellowing due to aging and increases whiteness, water vapor resistance, aging resistance, and corrosion resistance, thereby ultimately extending its service life. Finally, the addition of the compound increases the opacity of the fabric, thereby increasing the surface ink absorption of the product and improving the printability of the nonwoven fabric.

[0078] II. Flash spinning

[0079] The fibers were then subjected to flash spinning at a temperature of 210°C to obtain flash fibers. These fibers were then hot-pressed onto rollers at a temperature of 120°C and a linear pressure of 11 N / m to obtain polyethylene flash nonwoven fabric. The polyethylene flash nonwoven fabric underwent performance testing according to the corresponding national standard description in Example 1. Specific data are shown in Table 1.

[0080] Example 3

[0081] A method for manufacturing polyethylene flash nonwoven fabric, comprising the following technical steps:

[0082] I. Preparation of spinning solution

[0083] The spinning solution contains polyethylene, an ethylene-1-octene block copolymer modifier, and a spinning solvent.

[0084] The mass fraction of polyethylene in the spinning solution is 14%.

[0085] The mass fraction of the ethylene-1-octene block copolymer modifier in the mixture of polyethylene and the ethylene-1-octene block copolymer modifier is 8%.

[0086] The modified ethylene-1-octene block copolymer is a composite bilayer material in which a layer of zinc barium white is adsorbed on the surface of the ethylene-1-octene block copolymer.

[0087] The spinning solvent is 1,1,1,3,3-pentafluorobutane and 1H-perfluoroheptane, with a volume ratio of 2:1.

[0088] The preparation method of the modified ethylene-1-octene block copolymer is as follows: (1) Disperse the ethylene-1-octene block copolymer powder in concentrated sulfuric acid and heat treat it at 100-110℃ for 15-45 min, then filter and dry it to obtain the modified ethylene-1-octene block copolymer; (2) Disperse the modified ethylene-1-octene block copolymer in zinc sulfate solution, add it to barium chloride solution by microwave stirring to obtain a precipitate, which is a composite bilayer material with a layer of zinc barium white adsorbed on the surface of the ethylene-1-octene block copolymer.

[0089] The mass ratio of ethylene-1-octene block copolymer powder to zinc sulfate in zinc sulfate solution is 1:0.16;

[0090] The molar ratio of zinc sulfate in zinc sulfate solution to barium sulfide in barium sulfide solution is 1:1.25.

[0091] In the presence of concentrated sulfuric acid, the surface of ethylene-1-octene block copolymer (E-1-octene) microparticles undergoes sulfonation, forming sulfonic acid groups. The sulfonated E-1-octene block copolymer powder can then form barium sulfate and zinc sulfide with zinc and barium ions, achieving fixation through chelation by the sulfonic acid groups of the E-1-octene block copolymer, resulting in barium sulfate and zinc sulfide precipitates on the surface (a more effective method than physical mixing). Simultaneously, the E-1-octene block copolymer contains vinyl group fragments, exhibiting good compatibility with polyethylene, resulting in better uniform dispersion in polyethylene spinning solutions, increased flowability, and improved mechanical properties. The addition of the E-1-octene block copolymer-encapsulated zinc-barium white complex disrupts the flash fiber bundles during flash spinning, allowing the complex to penetrate between the fiber bundles. Furthermore, due to the excellent elastic recovery and stress relaxation properties of the E-1-octene block copolymer itself, the wet tensile strength of the flash nonwoven fabric under stress can be improved. Secondly, because the molecular chains of the ethylene-1-octene block copolymer in the modified ethylene-1-octene block copolymer consist of nonpolar saturated single bonds and lack polar groups, and due to the presence of zinc barium white components, it prevents yellowing due to aging and increases whiteness, water vapor resistance, aging resistance, and corrosion resistance, thereby ultimately extending its service life. Finally, the addition of the compound increases the opacity of the fabric, thereby increasing the surface ink absorption of the product and improving the printability of the nonwoven fabric.

[0092] II. Flash spinning

[0093] The fibers were then subjected to flash spinning at a temperature of 215℃ to obtain flash fibers, which were then hot-pressed onto rollers at a temperature of 125℃ and a linear pressure of 15 N / m to obtain polyethylene flash nonwoven fabric. The polyethylene flash nonwoven fabric underwent performance testing according to the corresponding national standard description in Example 1. Specific data are shown in Table 1.

[0094] Comparative Example 1

[0095] A method for manufacturing polyethylene flash nonwoven fabric, comprising the following technical steps:

[0096] I. Preparation of spinning solution

[0097] The spinning solution contains polyethylene and a spinning solvent.

[0098] The mass fraction of polyethylene in the spinning solution is 13.5%.

[0099] The spinning solvent is 1,1,1,3,3-pentafluorobutane and 1H-perfluoroheptane, with a volume ratio of 2:1.

[0100] II. Flash spinning

[0101] The fibers were then subjected to flash spinning at a temperature of 210°C to obtain flash fibers. These fibers were then hot-pressed onto rollers at a temperature of 120°C and a linear pressure of 11 N / m to obtain polyethylene flash nonwoven fabric. The polyethylene flash nonwoven fabric underwent performance testing according to the corresponding national standard description in Example 1. Specific data are shown in Table 1.

[0102] Comparative Example 2

[0103] A method for manufacturing polyethylene flash nonwoven fabric, comprising the following technical steps:

[0104] I. Preparation of spinning solution

[0105] The spinning solution contains polyethylene, an ethylene-1-octene block copolymer modifier, and a spinning solvent.

[0106] The mass fraction of polyethylene in the spinning solution is 13.5%.

[0107] The mass fraction of the ethylene-1-octene block copolymer modifier in the mixture of polyethylene and the ethylene-1-octene block copolymer modifier is 6%.

[0108] The modified ethylene-1-octene block copolymer is a mixture of ethylene-1-octene block copolymer and zinc barium white, which is simply a mixture; the mass ratio of ethylene-1-octene block copolymer to zinc barium white is 1:0.14.

[0109] The spinning solvent is 1,1,1,3,3-pentafluorobutane and 1H-perfluoroheptane, with a volume ratio of 2:1.

[0110] II. Flash spinning

[0111] The fibers were then subjected to flash spinning at a temperature of 210°C to obtain flash fibers. These fibers were then hot-pressed onto rollers at a temperature of 120°C and a linear pressure of 11 N / m to obtain polyethylene flash nonwoven fabric. The polyethylene flash nonwoven fabric underwent performance testing according to the corresponding national standard description in Example 1. Specific data are shown in Table 1.

[0112] Comparative Example 3

[0113] A method for manufacturing polyethylene flash nonwoven fabric, comprising the following technical steps:

[0114] I. Preparation of spinning solution

[0115] The spinning solution contains polyethylene, an ethylene-1-octene block copolymer modifier, and a spinning solvent.

[0116] The mass fraction of polyethylene in the spinning solution is 13.5%.

[0117] The mass fraction of the ethylene-1-octene block copolymer modifier in the mixture of polyethylene and the ethylene-1-octene block copolymer modifier is 1%.

[0118] The modified ethylene-1-octene block copolymer is a composite bilayer material in which a layer of zinc barium white is adsorbed on the surface of the ethylene-1-octene block copolymer.

[0119] The spinning solvent is 1,1,1,3,3-pentafluorobutane and 1H-perfluoroheptane, with a volume ratio of 2:1.

[0120] The preparation method of the modified ethylene-1-octene block copolymer is as follows: (1) Disperse the ethylene-1-octene block copolymer powder in concentrated sulfuric acid and heat treat it at 100-110℃ for 15-45 min, then filter and dry it to obtain the modified ethylene-1-octene block copolymer; (2) Disperse the modified ethylene-1-octene block copolymer in zinc sulfate solution, add it to barium chloride solution by microwave stirring to obtain a precipitate, which is a composite bilayer material with a layer of zinc barium white adsorbed on the surface of the ethylene-1-octene block copolymer.

[0121] The mass ratio of ethylene-1-octene block copolymer powder to zinc sulfate solution was 1:0.14.

[0122] The molar ratio of zinc sulfate in zinc sulfate solution to barium sulfide in barium sulfide solution is 1:1.15.

[0123] II. Flash spinning

[0124] The fibers were then subjected to flash spinning at a temperature of 210°C to obtain flash fibers. These fibers were then hot-pressed onto rollers at a temperature of 120°C and a linear pressure of 11 N / m to obtain polyethylene flash nonwoven fabric. The polyethylene flash nonwoven fabric underwent performance testing according to the corresponding national standard description in Example 1. Specific data are shown in Table 1.

[0125] Comparative Example 4

[0126] A method for manufacturing polyethylene flash nonwoven fabric, comprising the following technical steps:

[0127] I. Preparation of spinning solution

[0128] The spinning solution contains polyethylene, an ethylene-1-octene block copolymer modifier, and a spinning solvent.

[0129] The mass fraction of polyethylene in the spinning solution is 13.5%.

[0130] The mass fraction of the ethylene-1-octene block copolymer modifier in the mixture of polyethylene and the ethylene-1-octene block copolymer modifier is 2%.

[0131] The modified ethylene-1-octene block copolymer is a composite bilayer material in which a layer of zinc barium white is adsorbed on the surface of the ethylene-1-octene block copolymer.

[0132] The spinning solvent is 1,1,1,3,3-pentafluorobutane and 1H-perfluoroheptane, with a volume ratio of 2:1.

[0133] The preparation method of the modified ethylene-1-octene block copolymer is as follows: (1) Disperse the ethylene-1-octene block copolymer powder in concentrated sulfuric acid and heat treat it at 100-110℃ for 15-45 min, then filter and dry it to obtain the modified ethylene-1-octene block copolymer; (2) Disperse the modified ethylene-1-octene block copolymer in zinc sulfate solution, add it to barium chloride solution by microwave stirring to obtain a precipitate, which is a composite bilayer material with a layer of zinc barium white adsorbed on the surface of the ethylene-1-octene block copolymer.

[0134] The mass ratio of ethylene-1-octene block copolymer powder to zinc sulfate solution was 1:0.14.

[0135] The molar ratio of zinc sulfate in zinc sulfate solution to barium sulfide in barium sulfide solution is 1:1.15.

[0136] II. Flash spinning

[0137] The fibers were then subjected to flash spinning at a temperature of 210°C to obtain flash fibers. These fibers were then hot-pressed onto rollers at a temperature of 120°C and a linear pressure of 11 N / m to obtain polyethylene flash nonwoven fabric. The polyethylene flash nonwoven fabric underwent performance testing according to the corresponding national standard description in Example 1. Specific data are shown in Table 1.

[0138] Comparative Example 5

[0139] A method for manufacturing polyethylene flash nonwoven fabric, comprising the following technical steps:

[0140] I. Preparation of spinning solution

[0141] The spinning solution contains polyethylene, an ethylene-1-octene block copolymer modifier, and a spinning solvent.

[0142] The mass fraction of polyethylene in the spinning solution is 13.5%.

[0143] The mass fraction of the ethylene-1-octene block copolymer modifier in the mixture of polyethylene and the ethylene-1-octene block copolymer modifier is 3%.

[0144] The modified ethylene-1-octene block copolymer is a composite bilayer material in which a layer of zinc barium white is adsorbed on the surface of the ethylene-1-octene block copolymer.

[0145] The spinning solvent is 1,1,1,3,3-pentafluorobutane and 1H-perfluoroheptane, with a volume ratio of 2:1.

[0146] The preparation method of the modified ethylene-1-octene block copolymer is as follows: (1) Disperse the ethylene-1-octene block copolymer powder in concentrated sulfuric acid and heat treat it at 100-110℃ for 15-45 min, then filter and dry it to obtain the modified ethylene-1-octene block copolymer; (2) Disperse the modified ethylene-1-octene block copolymer in zinc sulfate solution, add it to barium chloride solution by microwave stirring to obtain a precipitate, which is a composite bilayer material with a layer of zinc barium white adsorbed on the surface of the ethylene-1-octene block copolymer.

[0147] The mass ratio of ethylene-1-octene block copolymer powder to zinc sulfate solution was 1:0.14.

[0148] The molar ratio of zinc sulfate in zinc sulfate solution to barium sulfide in barium sulfide solution is 1:1.15.

[0149] II. Flash spinning

[0150] The fibers were then subjected to flash spinning at a temperature of 210°C to obtain flash fibers. These fibers were then hot-pressed onto rollers at a temperature of 120°C and a linear pressure of 11 N / m to obtain polyethylene flash nonwoven fabric. The polyethylene flash nonwoven fabric underwent performance testing according to the corresponding national standard description in Example 1. Specific data are shown in Table 1.

[0151] Comparative Example 6

[0152] A method for manufacturing polyethylene flash nonwoven fabric, comprising the following technical steps:

[0153] I. Preparation of spinning solution

[0154] The spinning solution contains polyethylene, an ethylene-1-octene block copolymer modifier, and a spinning solvent.

[0155] The mass fraction of polyethylene in the spinning solution is 13.5%.

[0156] The mass fraction of the ethylene-1-octene block copolymer modifier in the mixture of polyethylene and the ethylene-1-octene block copolymer modifier is 10%.

[0157] The modified ethylene-1-octene block copolymer is a composite bilayer material in which a layer of zinc barium white is adsorbed on the surface of the ethylene-1-octene block copolymer.

[0158] The spinning solvent is 1,1,1,3,3-pentafluorobutane and 1H-perfluoroheptane, with a volume ratio of 2:1.

[0159] The preparation method of the modified ethylene-1-octene block copolymer is as follows: (1) Disperse the ethylene-1-octene block copolymer powder in concentrated sulfuric acid and heat treat it at 100-110℃ for 15-45 min, then filter and dry it to obtain the modified ethylene-1-octene block copolymer; (2) Disperse the modified ethylene-1-octene block copolymer in zinc sulfate solution, add it to barium chloride solution by microwave stirring to obtain a precipitate, which is a composite bilayer material with a layer of zinc barium white adsorbed on the surface of the ethylene-1-octene block copolymer.

[0160] The mass ratio of ethylene-1-octene block copolymer powder to zinc sulfate solution was 1:0.14.

[0161] The molar ratio of zinc sulfate in zinc sulfate solution to barium sulfide in barium sulfide solution is 1:1.15.

[0162] II. Flash spinning

[0163] The fibers were then subjected to flash spinning at a temperature of 210°C to obtain flash fibers. These fibers were then hot-pressed onto rollers at a temperature of 120°C and a linear pressure of 11 N / m to obtain polyethylene flash nonwoven fabric. The polyethylene flash nonwoven fabric underwent performance testing according to the corresponding national standard description in Example 1. Specific data are shown in Table 1.

[0164] Comparative Example 7

[0165] A method for manufacturing polyethylene flash nonwoven fabric, comprising the following technical steps:

[0166] I. Preparation of spinning solution

[0167] The spinning solution contains polyethylene, an ethylene-1-octene block copolymer modifier, and a spinning solvent.

[0168] The mass fraction of polyethylene in the spinning solution is 13.5%.

[0169] The mass fraction of the ethylene-1-octene block copolymer modifier in the mixture of polyethylene and the ethylene-1-octene block copolymer modifier is 12%.

[0170] The modified ethylene-1-octene block copolymer is a composite bilayer material in which a layer of zinc barium white is adsorbed on the surface of the ethylene-1-octene block copolymer.

[0171] The spinning solvent is 1,1,1,3,3-pentafluorobutane and 1H-perfluoroheptane, with a volume ratio of 2:1.

[0172] The preparation method of the modified ethylene-1-octene block copolymer is as follows: (1) Disperse the ethylene-1-octene block copolymer powder in concentrated sulfuric acid and heat treat it at 100-110℃ for 15-45 min, then filter and dry it to obtain the modified ethylene-1-octene block copolymer; (2) Disperse the modified ethylene-1-octene block copolymer in zinc sulfate solution, add it to barium chloride solution by microwave stirring to obtain a precipitate, which is a composite bilayer material with a layer of zinc barium white adsorbed on the surface of the ethylene-1-octene block copolymer.

[0173] The mass ratio of ethylene-1-octene block copolymer powder to zinc sulfate solution was 1:0.14.

[0174] The molar ratio of zinc sulfate in zinc sulfate solution to barium sulfide in barium sulfide solution is 1:1.15.

[0175] II. Flash spinning

[0176] The fibers were then subjected to flash spinning at a temperature of 210°C to obtain flash fibers. These fibers were then hot-pressed onto rollers at a temperature of 120°C and a linear pressure of 11 N / m to obtain polyethylene flash nonwoven fabric. The polyethylene flash nonwoven fabric underwent performance testing according to the corresponding national standard description in Example 1. Specific data are shown in Table 1.

[0177] Comparative Example 8

[0178] A method for manufacturing polyethylene flash nonwoven fabric, comprising the following technical steps:

[0179] I. Preparation of spinning solution

[0180] The spinning solution contains polyethylene, an ethylene-1-octene block copolymer modifier, and a spinning solvent.

[0181] The mass fraction of polyethylene in the spinning solution is 13.5%.

[0182] The mass fraction of the ethylene-1-octene block copolymer modifier in the mixture of polyethylene and the ethylene-1-octene block copolymer modifier is 14%.

[0183] The modified ethylene-1-octene block copolymer is a composite bilayer material in which a layer of zinc barium white is adsorbed on the surface of the ethylene-1-octene block copolymer.

[0184] The spinning solvent is 1,1,1,3,3-pentafluorobutane and 1H-perfluoroheptane, with a volume ratio of 2:1.

[0185] The preparation method of the modified ethylene-1-octene block copolymer is as follows: (1) Disperse the ethylene-1-octene block copolymer powder in concentrated sulfuric acid and heat treat it at 100-110℃ for 15-45 min, then filter and dry it to obtain the modified ethylene-1-octene block copolymer; (2) Disperse the modified ethylene-1-octene block copolymer in zinc sulfate solution, add it to barium chloride solution by microwave stirring to obtain a precipitate, which is a composite bilayer material with a layer of zinc barium white adsorbed on the surface of the ethylene-1-octene block copolymer.

[0186] The mass ratio of ethylene-1-octene block copolymer powder to zinc sulfate solution was 1:0.14.

[0187] The molar ratio of zinc sulfate in zinc sulfate solution to barium sulfide in barium sulfide solution is 1:1.15.

[0188] II. Flash spinning

[0189] The fibers were then subjected to flash spinning at a temperature of 210°C to obtain flash fibers. These fibers were then hot-pressed onto rollers at a temperature of 120°C and a linear pressure of 11 N / m to obtain polyethylene flash nonwoven fabric. The polyethylene flash nonwoven fabric underwent performance testing according to the corresponding national standard description in Example 1. Specific data are shown in Table 1.

[0190] Comparative Example 9

[0191] A method for manufacturing polyethylene flash nonwoven fabric, comprising the following technical steps:

[0192] I. Preparation of spinning solution

[0193] The spinning solution contains polyethylene, an ethylene-1-octene block copolymer modifier, and a spinning solvent.

[0194] The mass fraction of polyethylene in the spinning solution is 13.5%.

[0195] The mass fraction of the ethylene-1-octene block copolymer modifier in the mixture of polyethylene and the ethylene-1-octene block copolymer modifier is 6%.

[0196] The modified ethylene-1-octene block copolymer is a composite bilayer material in which a layer of zinc barium white is adsorbed on the surface of the ethylene-1-octene block copolymer.

[0197] The spinning solvent is 1,1,1,3,3-pentafluorobutane and 1H-perfluoroheptane, with a volume ratio of 2:1.

[0198] The preparation method of the modified ethylene-1-octene block copolymer is as follows: (1) Disperse the ethylene-1-octene block copolymer powder in concentrated sulfuric acid and heat treat it at 100-110℃ for 15-45 min, then filter and dry it to obtain the modified ethylene-1-octene block copolymer; (2) Disperse the modified ethylene-1-octene block copolymer in zinc sulfate solution, add it to barium chloride solution by microwave stirring to obtain a precipitate, which is a composite bilayer material with a layer of zinc barium white adsorbed on the surface of the ethylene-1-octene block copolymer.

[0199] The mass ratio of ethylene-1-octene block copolymer powder to zinc sulfate solution was 1:0.14.

[0200] The molar ratio of zinc sulfate in zinc sulfate solution to barium sulfide in barium sulfide solution is 1:1.15.

[0201] II. Flash spinning

[0202] The fibers were then subjected to flash spinning at a temperature of 210°C to obtain flash fibers. These fibers were then hot-pressed onto rollers at a temperature of 120°C and a linear pressure of 20 N / m to obtain polyethylene flash nonwoven fabric. The polyethylene flash nonwoven fabric underwent performance testing according to the corresponding national standard description in Example 1. Specific data are shown in Table 1.

[0203] Comparative Example 10

[0204] A method for manufacturing polyethylene flash nonwoven fabric, comprising the following technical steps:

[0205] I. Preparation of spinning solution

[0206] The spinning solution contains polyethylene, an ethylene-1-octene block copolymer modifier, and a spinning solvent.

[0207] The mass fraction of polyethylene in the spinning solution is 13.5%.

[0208] The mass fraction of the ethylene-1-octene block copolymer modifier in the mixture of polyethylene and the ethylene-1-octene block copolymer modifier is 6%.

[0209] The modified ethylene-1-octene block copolymer is a composite bilayer material in which a layer of zinc barium white is adsorbed on the surface of the ethylene-1-octene block copolymer.

[0210] The spinning solvent is 1,1,1,3,3-pentafluorobutane and 1H-perfluoroheptane, with a volume ratio of 2:1.

[0211] The preparation method of the modified ethylene-1-octene block copolymer is as follows: (1) Disperse the ethylene-1-octene block copolymer powder in concentrated sulfuric acid and heat treat it at 100-110℃ for 15-45 min, then filter and dry it to obtain the modified ethylene-1-octene block copolymer; (2) Disperse the modified ethylene-1-octene block copolymer in zinc sulfate solution, add it to barium chloride solution by microwave stirring to obtain a precipitate, which is a composite bilayer material with a layer of zinc barium white adsorbed on the surface of the ethylene-1-octene block copolymer.

[0212] The mass ratio of ethylene-1-octene block copolymer powder to zinc sulfate solution was 1:0.14.

[0213] The molar ratio of zinc sulfate in zinc sulfate solution to barium sulfide in barium sulfide solution is 1:1.15.

[0214] II. Flash spinning

[0215] The fibers were then spun using a flash spinning method at a temperature of 210℃ to obtain flash fibers. These fibers were then hot-pressed onto rollers at a temperature of 120℃ and a linear pressure of 3 N / m to obtain polyethylene flash nonwoven fabric. The polyethylene flash nonwoven fabric underwent performance testing according to the corresponding national standard description in Example 1. Specific data are shown in Table 1.

[0216] Table 1

[0217]

[0218] When Comparative Example 1 did not contain ethylene-1-octene block copolymer modifier, its performance was significantly reduced. When the ethylene-1-octene block copolymer modifier in Comparative Example 2 was a mixture of the two, its performance was also significantly reduced, but the data indicators were better than those of Comparative Example 1, but weaker than those of Example 2. When the content of ethylene-1-octene block copolymer modifier in Comparative Examples 3, 4, and 5 was low, its performance indicators were significantly reduced. However, when the content of ethylene-1-octene block copolymer modifier in Comparative Examples 6, 7, and 8 was high, its wet tensile strength tended to be stable and did not increase significantly with the increase of the ethylene-1-octene block copolymer modifier component. This is mainly because the ethylene-1-octene block copolymer modifier in polyethylene has reached a plateau, first rising linearly and then stabilizing in a plateau range. This is a data obtained through analysis and experimental verification in this application, and it is also a discovery of this application. When the linear pressure of Comparative Example 9 increases, the fibers in the nonwoven fabric are tightly bonded together. When the linear pressure of Comparative Example 10 decreases, the fibers in the nonwoven fabric are relatively loose, and the corresponding properties will change significantly.

[0219] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several improvements and modifications without departing from the concept of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A polyethylene flash-spun nonwoven fabric, which is made from a raw material of polyethylene and an ethylene-1-octene block copolymer modifier, characterized in that, The wet tensile strength is 1600-2400 N / m, the wet tensile strength retention rate is 0.55-0.70, and the opacity is 0.85-0.95; Under standard atmospheric conditions, the tensile strength of the same sample after being soaked is measured, and the soaking process conditions of the sample are as follows: first, the water temperature for soaking is 40 DEG C, and the soaking time is 8 hours; then, the temperature is raised to 60 DEG C, and the soaking time is 8 hours; The ethylene-1-octene block copolymer modifier is a composite double-layer material in which ethylene-1-octene block copolymer is adsorbed with a layer of zinc white on the surface; The preparation method of the ethylene-1-octene block copolymer modifier is as follows: (1) ethylene-1-octene block copolymer powder is dispersed in concentrated sulfuric acid and heated at 100-110 DEG C for 15-45 min, then filtered and dried to obtain modified ethylene-1-octene block copolymer; (2) the modified ethylene-1-octene block copolymer is dispersed in a zinc sulfate solution, and a barium chloride solution is added by microwave stirring to obtain a precipitate, which is a composite double-layer material in which ethylene-1-octene block copolymer is adsorbed with a layer of zinc white on the surface.

2. The polyethylene flash-spun nonwoven fabric according to claim 1, wherein The wet tensile strength of the polyethylene flash non-woven fabric is 1600-1800 N / m.

3. The polyethylene flash-spun nonwoven fabric of claim 1, wherein The wet tensile strength of the polyethylene flash non-woven fabric is 1800-2000 N / m.

4. The polyethylene flash-spun nonwoven fabric of claim 1, wherein The wet tensile strength of the polyethylene flash non-woven fabric is 2000-2200 N / m.

5. The polyethylene flash-spun nonwoven fabric of claim 1, wherein The wet tensile strength of the polyethylene flash non-woven fabric is 2200-2400 N / m.

6. The polyethylene flash-spun nonwoven fabric of claim 1, wherein The wet tensile strength retention rate of the polyethylene flash non-woven fabric is 0.55-0.

60.

7. The polyethylene flash-spun nonwoven fabric of claim 1, wherein The wet tensile strength retention rate of the polyethylene flash non-woven fabric is 0.60-0.

65.

8. The polyethylene flash-spun nonwoven fabric of claim 1, wherein The wet tensile strength retention rate of the polyethylene flash non-woven fabric is 0.65-0.

70.

9. The polyethylene flash-spun nonwoven fabric of claim 1, wherein The opacity of the polyethylene flash non-woven fabric is 0.85-0.

88.

10. The polyethylene flash-spun nonwoven fabric of claim 1, wherein The opacity of the polyethylene flash non-woven fabric is 0.88-0.

92.

11. The polyethylene flash-spun nonwoven fabric of claim 1, wherein The opacity of the polyethylene flash non-woven fabric is 0.92-0.95.

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