SMMS non-woven fabric with high air permeability and preparation method thereof

Abstract

The invention belongs to the technical field of non-woven fabrics, and particularly discloses a high-air-permeability SMMS non-woven fabric and a preparation method thereof. The SMMS non-woven fabric with the high air permeability is composed of a spunbond layer, a melt-blown layer and a spunbond layer, the composite material comprises the following components in parts by weight: 80-90 parts of polypropylene, 35-40 parts of an ethylene-vinyl acetate copolymer, 20-23 parts of modified coconut fiber, 15-18 parts of a seaweed extract, 10-13 parts of titanium dioxide, 9-12 parts of nano zinc oxide, 6-8 parts of polyethylene glycol, 2-3 parts of maleic anhydride grafted polypropylene, 3-5 parts of a titanate coupling agent and 1-3 parts of a micropore forming aid. The prepared SMMS non-woven fabric with high air permeability has good strength, air permeability and softness, and the durability of the non-woven fabric is further prolonged.

Description

Technical Field

[0001] The present application relates to the technical field of nonwoven fabrics, and in particular to a high-air-permeability SMMS nonwoven fabric and a preparation method thereof. Background Art

[0002] SMMS nonwoven fabric is a composite product of spunbond and meltblown. Its structure is usually composed of two layers of spunbond nonwoven fabric and two layers of meltblown nonwoven fabric through hot rolling and other processes, hence the name SMMS. SMMS nonwoven fabric has the properties of light weight, softness, breathability, and antibacterial, and is widely used in medical and health, home decoration, industry, environmental protection and other fields.

[0003] The spunbond layer is usually made of polypropylene raw materials and spunbond masterbatch mixed in a certain proportion, melt-spun to obtain a spunbond layer, and the meltblown layer is made of polypropylene raw materials that are melted and blown into ultrafine fibers, which are collected and formed into a meltblown fiber web to obtain a meltblown layer. The prepared spunbond layer fiber web and meltblown layer fiber web are stacked together in a certain order. Usually, the structure of SMMS non-woven fabric is two layers of spunbond layers sandwiched between two layers of meltblown layers, and the stacked fiber webs are consolidated to form a non-woven fabric.

[0004] In the prior art, the spunbond layer is made by mixing polypropylene raw materials and spunbond masterbatch in a certain proportion, melt spinning, and laying a web to obtain a spunbond layer; the meltblown layer is made by melting the polypropylene raw materials, blowing them into ultrafine fibers, collecting and forming a meltblown fiber web to obtain a meltblown layer; the prepared spunbond layer fiber web and meltblown layer fiber web are stacked together in a certain order for consolidation to form a non-woven fabric. Generally, the structure of SMMS non-woven fabric is two layers of spunbond layers sandwiched between two layers of meltblown layers.

[0005] The nonwoven fabric prepared by the above method has good mechanical properties, air permeability, light weight, softness and good filtering performance. However, the nonwoven fabric may be subjected to mechanical stress during use, such as stretching, tearing, etc., and these stresses may cause the nonwoven fabric to be damaged. Summary of the invention

[0006] In order to improve the problem that non-woven fabrics are easily damaged by external forces, the present application provides a high-permeability SMMS non-woven fabric and a preparation method thereof.

[0007] The present application provides a high air permeability SMMS non-woven fabric, which adopts the following technical solution: A high-air-permeability SMMS non-woven fabric consists of a spunbond layer, a meltblown layer and a spunbond layer. The raw materials of the spunbond layer include, by weight: 80-90 parts of polypropylene, 35-40 parts of ethylene-vinyl acetate copolymer, 20-23 parts of modified coconut shell fiber, 15-18 parts of seaweed extract, 10-13 parts of titanium dioxide, 9-12 parts of nano zinc oxide, 6-8 parts of polyethylene glycol, 2-3 parts of maleic anhydride grafted polypropylene, 3-5 parts of titanate coupling agent and 1-3 parts of micropore forming auxiliary agent.

[0008] By adopting the above technical solution, the spunbond layer is made by spinning and bonding process, with high strength and good dimensional stability, providing structural support and wear resistance for SMMS non-woven fabric. The meltblown layer is made by high-temperature melting and spraying fiber filaments, with ultra-fine fiber structure and good filtration performance. At the same time, there are a large number of tiny pores between the fibers of the meltblown layer, which helps to maintain air permeability, making the SMMS non-woven fabric have excellent air permeability.

[0009] Among the raw materials of the spunbond layer, polypropylene has good spinnability and thermal stability, providing good structural support and strength for the spunbond layer. Ethylene-vinyl acetate copolymer can improve the toughness, wear resistance and aging resistance of polypropylene, and together with polypropylene, it constitutes the main matrix of the spunbond layer. Maleic anhydride grafted polypropylene allows the components to be mixed evenly, ensuring the uniform dispersion and stability of the system. Modified coconut shell fiber has better hydrophilicity and adhesion to the polymer matrix, increases the softness and hygroscopicity of the spunbond layer, and improves the interfacial bonding strength between the fiber and the polymer matrix. Seaweed extract is biocompatible and degradable, giving the spunbond layer antibacterial, antibacterial, moisturizing and skin care properties. Titanium dioxide has excellent hiding and spectral characteristics, improves the whiteness and brightness of the spunbond layer, and has a certain UV protection effect.

[0010] Nano zinc oxide has antibacterial, deodorizing and UV protection properties, further enhancing the antibacterial and protective properties of the spunbond layer. Polyethylene glycol has strong hydrophilicity and miscibility with water, which can improve the softness and wear resistance of the spunbond layer while preventing the generation of static electricity. Titanate coupling agents can improve the interfacial interaction between inorganic fillers and organic polymers, helping to improve the compatibility and dispersibility between various raw materials in the spunbond layer. Micropore forming aids can form tiny pore structures in the spunbond layer, helping to improve the air permeability and filtration performance of the spunbond layer.

[0011] The combination of various raw materials in the spunbond layer provides good structural support and strength, ensuring that the spunbond layer has sufficient strength and stability. The microporous structure in the spunbond layer helps to improve the air permeability and filtration performance of the non-woven fabric. By adding ingredients such as modified coconut shell fiber, seaweed extract, titanium dioxide and nano zinc oxide, the spunbond layer can be given special properties such as antibacterial, antibacterial, moisturizing and skin care. Titanate coupling agents and polyethylene glycol can improve the compatibility and dispersibility between various raw materials in the spunbond layer, help ensure the uniformity and stability of the spunbond layer, and improve the overall quality of the product.

[0012] Preferably, the method for preparing the modified coconut shell fiber comprises the following steps: (1) placing coconut shell fiber in a NaOH solution, stirring for 1-2 hours, washing with water, drying, and then dispersing in deionized water, adding cocamidopropyl betaine, stirring for 1-2 hours at a temperature of 40-45° C., filtering, and drying to obtain pretreated coconut shell fiber; (2) dispersing the modified carbon black in deionized water, ultrasonically treating the water at a temperature of 60-65° C. for 1-2 h, adding the pretreated coconut shell fiber of step (1), continuing ultrasonication for 2-3 h, filtering, and drying to obtain a mixture; (3) spraying the mixture of step (2) with an aqueous solution of seaweed gel, and drying to obtain modified coconut shell fiber.

[0013] By adopting the above technical scheme, the surface of the coconut shell fiber is eroded to a certain extent by using NaOH solution, so that the surface of the coconut shell fiber becomes rough and porous, and the specific surface area of ​​the coconut shell fiber is increased, and then cocamidopropyl betaine is added to the coconut shell fiber after being dispersed in deionized water. Cocamidopropyl betaine has good solubility and compatibility, and can significantly improve the hydrophilicity of the surface of the coconut shell fiber, making the coconut shell fiber more easily interact with water molecules, thereby improving the hydrophilicity of the coconut shell fiber.

[0014] Modified carbon black has good reinforcement, weather resistance and UV resistance. Modified carbon black can be loaded on the surface and structure of coconut shell fiber to increase the strength and toughness of coconut shell fiber. Spraying seaweed gel aqueous solution has certain viscosity and film-forming properties, which can make the modified carbon black stably bonded to the coconut shell fiber structure, forming a more stable structure and improving the comprehensive performance of modified coconut shell fiber. Subsequent application in the spunbond layer improves the mechanical properties, air permeability, weather resistance, UV resistance and flame retardancy of the spunbond layer.

[0015] Preferably, the mass ratio of the coconut shell fiber, modified carbon black and alginate aqueous solution is 1:0.4-0.6:0.08-0.09.

[0016] By adopting the above technical scheme, the mass ratio of coconut husk fiber, modified carbon black and seaweed gel solution is further limited within a certain range, and the modified coconut husk fiber obtained has good mechanical properties, weather resistance and ultraviolet resistance. Coconut husk fiber has the characteristics of light weight, high strength, corrosion resistance, etc., and the modified carbon black has good reinforcing properties, flame retardancy and ultraviolet resistance. The modified carbon black can be loaded on the surface and structure of coconut husk fiber, and the strength, weather resistance and ultraviolet resistance of coconut husk fiber are increased. The seaweed gel solution has good film-forming properties and viscosity, can coat coconut husk fiber, can make the modified carbon black stably bonded in the coconut husk fiber structure, form a tighter fiber network, and improve the comprehensive performance of coconut husk fiber. Subsequent application in the spunbond layer improves the overall mechanical strength, stability, flame retardancy and durability of the spunbond layer.

[0017] Preferably, the preparation method of the modified carbon black comprises the following steps: immersing the carbon black in a sodium hydroxide solution, ultrasonicating for 10-15 minutes, the ultrasonic frequency being 20-22kHz, washing with water after the ultrasonication, drying, and then ball milling, the ball milling time being 20-22 minutes, the ball milling temperature being 50-55°C, the ball milling speed being 200-210rpm, and drying after the ball milling to obtain the treated carbon black; dispersing the treated carbon black in deionized water, adding nanosilver particles, lignin and sodium dodecylbenzene sulfonate, stirring at a temperature of 70-75°C for 1-2 hours, and drying to obtain the modified carbon black.

[0018] By adopting the above technical solution, the surface of carbon black is treated with sodium hydroxide solution, which reacts with the functional groups on the surface of carbon black, reduces the electrostatic repulsion and hydrogen bonding between carbon black particles, and thus improves the dispersibility of carbon black in water. The treated carbon black is dispersed in deionized water, and nanosilver particles, lignin and sodium dodecylbenzene sulfonate are added. The nanosilver particles have excellent antibacterial properties. When added to the treated carbon black dispersion, the nanosilver particles will adhere to the surface of the treated carbon black, increasing the antibacterial properties of carbon black. Lignin has excellent stability and adhesiveness, which allows the nanosilver particles to stably adhere to the surface of carbon black, increasing the mechanical properties and antibacterial properties of carbon black. Sodium dodecylbenzene sulfonate has good dispersing and emulsifying properties, effectively reducing the surface tension between carbon black particles, promoting the uniform dispersion of carbon black in deionized water, and forming a more uniform dispersion system.

[0019] The synergistic effect of nanosilver particles, lignin and sodium dodecylbenzene sulfonate balances the interaction between carbon black particles, thereby improving the stability, antibacterial and mechanical properties of the dispersion. It will then be applied to high-permeability SMMS non-woven fabrics to improve their mechanical properties (tensile strength, tear strength and abrasion resistance), antibacterial properties, weather resistance and stability.

[0020] Preferably, the method for preparing the seaweed extract comprises the following steps: (1) removing sediment from seaweed, cutting into blocks, freezing, and crushing into small particles, dispersing the particles in methanol, stirring them sufficiently, performing ultrasonic extraction and filtering to obtain a filtrate, and evaporating the filtrate to dryness to obtain a primary seaweed extract; (2) dispersing the primary seaweed extract of step (1) in methanol, stirring at 110-120° C., heating under reflux for 3-5 hours, and centrifuging to obtain a supernatant; (3) The supernatant of step (2) is evaporated to dryness to obtain a fine seaweed extract, the fine seaweed extract is dispersed in deionized water, nano-silicon dioxide, sodium sulfate and modified starch are added, stirred at a temperature of 70-75° C. for 1-2 h, dried, and ground to obtain a seaweed extract.

[0021] By adopting the above technical solution, the seaweed is cleaned and frozen to reduce the water content of the seaweed, making it easier to break when crushed, and reducing the damage to the active ingredients of the seaweed caused by the heat generated during the crushing process. Methanol as a solvent can dissolve various active ingredients in seaweed, and ultrasound can promote the active ingredients in seaweed to dissolve faster in methanol. The filtrate is evaporated to dryness to obtain the primary seaweed extract, which contains various active ingredients in seaweed.

[0022] The seaweed primary extract is further purified, and heating reflux is performed to ensure that the active ingredients are transferred from the primary extract to the methanol solvent and that the active ingredients are fully extracted. Centrifugation is performed to ensure that the active ingredient content in the supernatant is the highest, while removing as much solid impurities as possible.

[0023] Nano-silicon dioxide has excellent mechanical properties, wear resistance, stability and dispersibility, and can be loaded on the surface of seaweed extract particles. Sodium sulfate has good dispersibility and stability, making nano-silicon dioxide and seaweed extract evenly dispersed. Modified starch has good thickening and stabilizing effects, increasing the viscosity of the solution, making nano-silicon dioxide and seaweed extract particles adhere closely, and increasing the mechanical properties of seaweed extract. It will be subsequently applied to high-permeability SMMS non-woven fabrics to improve the antibacterial properties, air permeability, strength and toughness of high-permeability SMMS non-woven fabrics.

[0024] Preferably, the mass ratio of the seaweed primary extract, nano-silicon dioxide and modified starch is 1:0.7-0.8:0.3-0.5.

[0025] By adopting the above technical scheme, the mass ratio of seaweed primary extract, nano-silicon dioxide and modified starch is further limited within a certain range, and the obtained seaweed primary extract has good antibacterial properties, mechanical properties and wear resistance. The seaweed primary extract has good antibacterial properties, and the nano-silicon dioxide has good mechanical properties and wear resistance. The nano-silicon dioxide can be loaded on the surface of the seaweed primary extract particles. The modified starch has certain viscosity and film-forming properties, so that the nano-silicon dioxide can stably adhere to the surface of the seaweed primary extract particles, thereby increasing the performance stability of the seaweed primary extract. It is subsequently applied to high-permeability SMMS non-woven fabrics to improve the air permeability, antibacterial properties, wear resistance, strength and toughness of the high-permeability SMMS non-woven fabrics.

[0026] Preferably, the preparation method of the modified starch comprises the following steps: grinding corn starch until the particle size passes the sieve, then dispersing the corn starch in a sodium hydroxide solution, stirring at a temperature of 55-60°C for 6-8h, centrifuging, decanting the supernatant, filtering and drying to obtain pretreated starch, dispersing the pretreated starch in deionized water, adding chitosan fiber and gelatin, stirring at a temperature of 70-75°C for 1-2h, and drying to obtain modified starch.

[0027] By adopting the above technical scheme, the hydroxyl groups on the molecular chain of the starch treated with sodium hydroxide solution are partially ionized, which increases the flexibility of the starch molecular chain and improves the acid resistance, heat resistance and stability of the starch. The pretreated starch is dispersed in deionized water, and chitosan fiber and gelatin are added. The chitosan fiber has certain strength and toughness, and the gelatin has good film-forming and biodegradability. The interaction between starch, gelatin and chitosan fiber can form a tighter structure, thereby improving the overall mechanical strength and viscosity. It is subsequently used to prepare seaweed extract. The obtained seaweed extract has good viscosity, film-forming and mechanical properties, and has a good effect on the subsequent preparation of high-permeability SMMS non-woven fabrics.

[0028] Preferably, the method for preparing the meltblown layer comprises the following steps: drying the raw materials for the meltblown layer, extruding, spinning into fibers, forming a mesh surface, and solidifying to obtain the meltblown layer.

[0029] By adopting the above technical solution, the dried raw materials are fed into the screw extruder, and the raw materials are melted and plasticized through the rotation and heating of the screw. Under the pressure of the melt itself, the melt is ejected from the spinneret hole. These fine fibers are quickly cooled and solidified under the traction of the high-speed airflow to form fibers with certain strength and toughness. The fibers formed by spinning are collected on the mesh curtain to form a fiber web to obtain a melt-blown layer.

[0030] Preferably, the raw material of the meltblown layer is composed of 90-95% of meltblown masterbatch and 5-10% of high hydrostatic pressure masterbatch according to weight percentage.

[0031] By adopting the above technical scheme, the meltblown masterbatch improves the stability, durability and processing performance of the meltblown layer, and the high hydrostatic pressure masterbatch can significantly improve the waterproof performance and durability of the meltblown layer. The meltblown layer obtained by combining the meltblown masterbatch and the high hydrostatic pressure masterbatch has excellent comprehensive performance.

[0032] In the second aspect, the present application also provides a method for preparing a high-permeability SMMS non-woven fabric, comprising the following steps: uniformly mixing polypropylene, ethylene-vinyl acetate copolymer, modified coconut shell fiber, seaweed extract, titanium dioxide, nano zinc oxide, polyethylene glycol, titanate coupling agent, maleic anhydride grafted polypropylene and micropore forming additive, and forming a primary fiber web through melt extrusion, spinning, stretching and web forming; and then pre-curing and main curing treatment to obtain a spunbond layer; The spunbond layer, the meltblown layer and the spunbond layer are compounded at a compounding temperature of 145-150° C. and a pressure of 50-55 KPa to obtain a high air permeability SMMS non-woven fabric.

[0033] By adopting the above technical scheme and the above preparation method, the operation is simple and the process time is short, which helps to improve the production efficiency of preparing high-permeability SMMS non-woven fabrics. The obtained high-permeability SMMS non-woven fabrics have good mechanical properties, wear resistance and durability.

[0034] In summary, this application has the following beneficial effects: 1. The spunbond layer in this application has high strength and good dimensional stability, providing structural support and wear resistance for the SMMS nonwoven fabric. The meltblown layer has an ultrafine fiber structure and good filtration performance. At the same time, there are a large number of tiny pores between the fibers of the meltblown layer, which helps to maintain air permeability, making the SMMS nonwoven fabric have excellent air permeability.

[0035] 2. The modified coconut shell fiber in the present application has better hydrophilicity and adhesion to the polymer matrix, increases the softness and hygroscopicity of the spunbond layer, and improves the interfacial bonding strength between the fiber and the polymer matrix.

[0036] 3. The seaweed extract in the present application is biocompatible and degradable, and imparts antibacterial, antimicrobial, moisturizing and skin-care properties to the spunbond layer. DETAILED DESCRIPTION

[0037] The present application is further described in detail below in conjunction with embodiments.

[0038] The raw materials used in the examples and comparative examples can all be obtained commercially.

[0039] Preparation example of modified coconut shell fiber Preparation Example 1-1 The preparation method of modified coconut shell fiber comprises the following steps: (1) 30 kg of coconut shell fiber was placed in 50 L of 2% NaOH solution, stirred for 1.5 h, washed with water, dried, and dispersed in 55 L of deionized water, 2 kg of cocamidopropyl betaine was added, stirred at 45 ° C for 1.5 h, filtered, and dried to obtain pretreated coconut shell fiber; (2) dispersing the modified carbon black in 80 L of deionized water, ultrasonically treating at 65° C. for 2 h, adding the pretreated coconut shell fiber of step (1), continuing ultrasonication for 3 h, filtering, and drying to obtain a mixture; (3) spraying the mixture of step (2) with an aqueous solution of seaweed gel, and drying to obtain modified coconut shell fiber.

[0040] The mass ratio of coconut shell fiber, modified carbon black and alginate aqueous solution is 1:0.4:0.09.

[0041] The preparation method of modified carbon black comprises the following steps: placing 25 kg of carbon black in 40 L of sodium hydroxide solution with a mass fraction of 5% for immersion, ultrasonicating for 15 minutes at an ultrasonic frequency of 22 kHz, washing with water, drying, and then ball milling after the ultrasonication, wherein the ball milling time is 22 minutes, the ball milling temperature is 50 DEG C, and the ball milling speed is 210 rpm. After the ball milling is completed, drying is performed to obtain the treated carbon black; dispersing the treated carbon black in 70 L of deionized water, adding 8 kg of nano silver particles, 5 kg of lignin and 3 kg of sodium dodecylbenzene sulfonate, stirring at a temperature of 75 DEG C for 2 hours, and drying to obtain the modified carbon black.

[0042] Preparation Example 1-2 The difference from Preparation Example 1-1 is that in step (2), no modified carbon black is added.

[0043] Preparation Example 1-3 The difference from Preparation Example 1-1 is that in step (3), no alginate aqueous solution is added.

[0044] Preparation Example 1-4 The difference from Preparation Example 1-1 is that the mass ratio of coconut shell fiber, modified carbon black and alginate aqueous solution is 1:0.6:0.08.

[0045] Preparation Example 1-5 The difference from Preparation Example 1-1 is that the mass ratio of coconut shell fiber, modified carbon black and alginate aqueous solution is 1:0.1:0.13.

[0046] Preparation Example 1-6 The difference from Preparation Example 1-1 is that in the preparation method of modified carbon black, no nano silver particles are added.

[0047] Preparation Example 1-7 The difference from Preparation Example 1-1 is that in the preparation method of modified carbon black, no lignin is added.

[0048] Preparation example of seaweed extract Preparation Example 2-1 The preparation method of seaweed extract comprises the following steps: (1) removing sediment from 38 kg of seaweed, cutting into blocks, freezing, and crushing into small particles, dispersing the particles in 70 L of methanol, stirring them evenly, performing ultrasonic extraction and filtering to obtain a filtrate, and evaporating the filtrate to dryness to obtain a primary seaweed extract; (2) dispersing the primary seaweed extract of step (1) in 120 L of methanol, stirring at 300 r / min at 120° C., heating and refluxing for 5 h, and centrifuging the reflux liquid at 3500 rpm to obtain a supernatant; (3) The supernatant of step (2) is evaporated to dryness to obtain a fine seaweed extract, the fine seaweed extract is dispersed in 100 L of deionized water, nano-silicon dioxide, 3 kg of sodium sulfate and modified starch are added, stirred at a temperature of 75° C. for 2 h, dried, and ground to obtain a seaweed extract.

[0049] The mass ratio of seaweed primary extract, nano-silicon dioxide and modified starch is 1:0.7:0.5.

[0050] The preparation method of modified starch comprises the following steps: grinding 20 kg corn starch to a particle size of 200 mesh, dispersing the mixture in 40 L sodium hydroxide solution with a mass fraction of 2%, stirring the mixture at 60° C. for 8 h, centrifuging the mixture, removing the supernatant, filtering the mixture, and drying the mixture to obtain pretreated starch; dispersing the pretreated starch in 100 L deionized water, adding 6 kg chitosan fiber and 3 kg gelatin, stirring the mixture at 75° C. for 2 h, and drying the mixture to obtain modified starch.

[0051] Preparation Example 2-2 The difference from Preparation Example 2-1 is that in step (3), no nano-silicon dioxide is added.

[0052] Preparation Example 2-3 The difference from Preparation Example 2-1 is that in step (3), no modified starch is added.

[0053] Preparation Example 2-4 The difference from Preparation Example 2-1 is that the mass ratio of the seaweed primary extract, nano-silicon dioxide and modified starch is 1:0.8:0.3.

[0054] Preparation Example 2-5 The difference from Preparation Example 2-1 is that the mass ratio of the seaweed primary extract, nano-silicon dioxide and modified starch is 1:0.1:0.8.

[0055] Preparation Example 2-6 The difference from Preparation Example 2-1 is that chitosan fiber is not added in the preparation method of modified starch.

[0056] Preparation Example 2-7 The difference from Preparation Example 2-1 is that gelatin is not added in the preparation method of the modified starch. Example

[0057] Example 1 A high-air-permeability SMMS non-woven fabric consists of a spunbond layer, a meltblown layer and a spunbond layer. The raw materials of the spunbond layer include, by weight: 80 kg of polypropylene, 35 kg of ethylene-vinyl acetate copolymer, 20 kg of modified coconut shell fiber, 15 kg of seaweed extract, 10 kg of titanium dioxide, 12 kg of nano oxygen, 6-8 kg of polyethylene glycol, 2 kg of maleic anhydride grafted polypropylene, 3 kg of titanate coupling agent and 1 kg of micropore forming auxiliary agent.

[0058] Wherein, the titanate coupling agent is titanate coupling agent HY-311, and the micropore forming auxiliary agent is sodium bicarbonate.

[0059] The preparation method of the meltblown layer comprises the following steps: drying the raw material of the meltblown layer, extruding, spinning into fibers, forming a mesh surface, and solidifying to obtain a meltblown layer. The meltblown layer is extruded by a 180°C screw extruder, and then transported to a spinning box after melt filtration. The temperature is maintained at 220°C during the process. The extrusion pressure of the spinning box is 1MPa, the air side wind pressure is 40Kpa, the temperature is 210°C, and the strong hot air positive pressure with a spray pressure of 0.03MPa is stretched into ultra-fine fibers, falls into the mesh surface, and solidifies at 160°C for 30 minutes to obtain a meltblown layer. The fineness of the obtained meltblown layer fiber is less than 0.01Den.

[0060] The raw materials for the meltblown layer are composed of 95 kg of meltblown masterbatch and 5 kg of high hydrostatic pressure masterbatch; the meltblown masterbatch is purchased from Shanghai Haosucheng New Materials Co., Ltd., and the high hydrostatic pressure masterbatch is purchased from Dezhou Gemini New Materials Co., Ltd.

[0061] The preparation method of the high-permeability SMMS non-woven fabric comprises the following steps: uniformly mixing polypropylene, ethylene-vinyl acetate copolymer, modified coconut shell fiber, seaweed extract, titanium dioxide, nano zinc oxide, polyethylene glycol, titanate coupling agent, maleic anhydride grafted polypropylene and micropore forming auxiliary agent, and forming a primary fiber web through melt extrusion, spinning, stretching and web forming; and then obtaining a spunbond layer through pre-curing and main curing treatment; The spunbond layer, the meltblown layer and the spunbond layer are compounded by a hot rolling mill with a temperature of 145° C. and a pressure of 50 KPa to obtain a high-permeability SMMS non-woven fabric.

[0062] The preparation process of the spunbond layer includes: mixing the raw materials of the spunbond layer, extruding them with a screw extruder, the temperature of the screw extruder is 210°C, and then conveying them to the spinning box after melt filtration. During the process, the temperature is maintained at 202°C, the extrusion pressure of the spinning box is 5MPa, the air side wind pressure is 2Kpa, the wind speed is 20m / s, the temperature is 10°C, and the spunbond layer is obtained through cold air positive pressure drawing and web laying. The fiber fineness of the obtained spunbond layer is 1.10Den.

[0063] The pre-curing temperature is 130℃, the time is 3min; the main curing temperature is 170℃, the time is 1h.

[0064] The modified coconut shell fiber was prepared by using Preparation Example 1-1; and the seaweed extract was prepared by using Preparation Example 2-1.

[0065] Example 2 A high air permeability SMMS non-woven fabric, which differs from Example 1 in that the raw materials of the spunbond layer include, by weight: 90 kg of polypropylene, 40 kg of ethylene-vinyl acetate copolymer, 23 kg of modified coconut shell fiber, 18 kg of seaweed extract, 13 kg of titanium dioxide, 9 kg of nano zinc oxide, 8 kg of polyethylene glycol, 3 kg of maleic anhydride grafted polypropylene, 5 kg of titanate coupling agent and 3 kg of micropore forming auxiliary agent.

[0066] Example 3 A high air permeability SMMS non-woven fabric, which is different from Example 1 in that the modified coconut shell fiber is prepared using Preparation Example 1-2.

[0067] Example 4 A high air permeability SMMS non-woven fabric, which is different from Example 1 in that the modified coconut shell fiber is prepared using Preparation Examples 1-3.

[0068] Example 5 A high air permeability SMMS non-woven fabric, which is different from Example 1 in that the modified coconut shell fiber is prepared using Preparation Examples 1-4.

[0069] Example 6 A high air permeability SMMS non-woven fabric, which is different from Example 1 in that the modified coconut shell fiber is prepared using Preparation Examples 1-5.

[0070] Example 7 A high air permeability SMMS non-woven fabric, which is different from Example 1 in that the modified coconut shell fiber is prepared using Preparation Examples 1-6.

[0071] Example 8 A high air permeability SMMS non-woven fabric, which is different from Example 1 in that the modified coconut shell fiber is prepared using Preparation Examples 1-7.

[0072] Example 9 A high air permeability SMMS non-woven fabric, which is different from Example 1 in that the seaweed extract is prepared using Preparation Example 2-2.

[0073] Example 10 A high air permeability SMMS non-woven fabric, which is different from Example 1 in that the seaweed extract is prepared using Preparation Example 2-3.

[0074] Embodiment 11 A high air permeability SMMS non-woven fabric, which is different from Example 1 in that the seaweed extract is prepared using Preparation Examples 2-4.

[0075] Example 12 A high air permeability SMMS non-woven fabric, which is different from Example 1 in that the seaweed extract is prepared using Preparation Examples 2-5.

[0076] Example 13 A high air permeability SMMS non-woven fabric, which is different from Example 1 in that the seaweed extract is prepared using Preparation Examples 2-6.

[0077] Embodiment 14 A high air permeability SMMS non-woven fabric, which is different from Example 1 in that the seaweed extract is prepared using Preparation Examples 2-7.

[0078] Comparative Example Comparative Example 1 A high air permeability SMMS non-woven fabric, which differs from Example 1 in that modified coconut shell fiber is not added.

[0079] Comparative Example 2 A high air permeability SMMS nonwoven fabric, which is different from Example 1 in that the modified coconut shell fiber is replaced by an equal amount of coconut shell fiber.

[0080] Comparative Example 3 A high air permeability SMMS non-woven fabric, which differs from Example 1 in that no seaweed extract is added.

[0081] Performance testing The high air permeability SMMS non-woven fabrics prepared in Examples 1-14 and Comparative Examples 1-3 were subjected to performance tests; the sample size was 100 mm*100 mm, the reference standards for various performance tests were shown in Table 1, and the test results were shown in Table 1.

[0082] Table 1 Test data of embodiments and comparative examples As can be seen from Table 1, the high air permeability SMMS nonwoven fabrics prepared in Examples 1-2 of the present application have good mechanical properties, air permeability and softness, wherein the longitudinal / lateral strength of Example 1 is 42.56N / 25cm and 30.23N / 25cm respectively; the longitudinal / lateral elongation is 63.21% and 78.56% respectively; the longitudinal / lateral softness is 12.55mN and 22.35mN respectively, and the air permeability is 325. This shows that the prepared high air permeability SMMS nonwoven fabric has good mechanical properties and mechanical strength, and the various raw materials in the present application ensure the uniformity and stability of the spunbond layer, improve the overall quality of the product, and extend the durability of the nonwoven fabric.

[0083] In the preparation method of the modified coconut shell fiber of Examples 3-4, modified carbon black and alginate solution are not added respectively. In Examples 5-6, the mass ratio of coconut shell fiber, modified carbon black and alginate solution is changed. It can be seen from Table 1 that the test results of longitudinal / transverse strength, longitudinal / transverse elongation, longitudinal / transverse softness and air permeability of Examples 3-4 are significantly worse than those of Examples 1-2 and Example 5, while the corresponding performance test of Example 6 is better than that of Examples 3-4, but worse than that of Examples 1 and 5, indicating that the alginate solution has good film-forming property and viscosity, and the coconut shell fiber is coated, so that the modified carbon black can be stably bonded to the coconut shell fiber structure to form a tighter fiber network, thereby improving the comprehensive performance of the coconut shell fiber, and is subsequently applied to the spunbond layer to improve the overall mechanical strength, stability and durability of the spunbond layer.

[0084] In the preparation method of modified carbon black of Examples 7-8, nano silver particles and lignin are not added respectively. As can be seen from Table 1, the test results of longitudinal / transverse strength, longitudinal / transverse elongation, longitudinal / transverse softness and air permeability are significantly worse than those of Examples 1-2, but better than those of Example 3, indicating that the synergistic effect of nano silver particles, lignin and sodium dodecylbenzene sulfonate balances the interaction force between carbon black particles, thereby improving the stability, antibacterial and mechanical properties of the dispersion. It is subsequently applied to high-permeability SMMS non-woven fabrics to improve the mechanical properties (tensile strength, tear strength and wear resistance), antibacterial properties, weather resistance and stability of SMMS non-woven fabrics.

[0085] In the preparation methods of seaweed extracts in Examples 9-10, nano-silicon dioxide and modified starch are not added respectively. In Examples 11-12, the mass ratio of seaweed primary extract, nano-silicon dioxide and modified starch is changed. As can be seen from Table 1, the test results of longitudinal / transverse strength, longitudinal / transverse elongation, longitudinal / transverse softness and air permeability of Examples 9-10 are significantly worse than those of Examples 1-2 and Example 11, while the corresponding performance test of Example 12 is better than that of Examples 9-10, but worse than that of Examples 1 and 11, indicating that modified starch has good thickening and stabilizing effects, increases the viscosity of the solution, makes the nano-silicon dioxide and seaweed extract particles adhere closely, and increases the mechanical properties of the seaweed extract. It is subsequently applied to high-permeability SMMS non-woven fabrics to improve the antibacterial properties, air permeability, strength and toughness of high-permeability SMMS non-woven fabrics.

[0086] In the preparation method of modified starch in Examples 13-14, chitosan fiber and gelatin are not added respectively. As can be seen from Table 1, the test results of longitudinal / transverse strength, longitudinal / transverse elongation, longitudinal / transverse softness and air permeability are significantly worse than those in Examples 1-2, but better than those in Example 10, indicating that the interaction between starch, gelatin and chitosan fiber can form a tighter structure, thereby improving the overall mechanical strength and viscosity. It is subsequently used to prepare seaweed extract. The obtained seaweed extract has good viscosity, film-forming property and mechanical properties, which has a good effect on the subsequent preparation of high permeability SMMS non-woven fabric.

[0087] In Comparative Examples 1 and 3, no modified coconut shell fiber or seaweed extract is added. As can be seen from Table 1, the test results of longitudinal / transverse strength, longitudinal / transverse elongation, longitudinal / transverse softness and air permeability of Comparative Examples 1 and 3 are significantly worse than those of Examples 1-2, indicating that the modified coconut shell fiber has better hydrophilicity and adhesion to the polymer matrix, increases the softness and hygroscopicity of the spunbond layer, and improves the interfacial bonding strength and mechanical properties between the fiber and the polymer matrix; the seaweed extract has biocompatibility and degradability, gives the spunbond layer antibacterial, antibacterial, moisturizing and skin care properties, and improves the antibacterial and mechanical properties of the non-woven fabric.

[0088] In Comparative Example 2, the modified coconut shell fiber is replaced by an equal amount of coconut shell fiber. It can be seen from Table 1 that compared with Example 1, the test results of the longitudinal / transverse strength, longitudinal / transverse elongation, longitudinal / transverse softness and air permeability of Comparative Example 2 are significantly worse than those of Examples 1-2, but better than Comparative Example 1, indicating that the modified coconut shell fiber of the present application has good mechanical properties, thereby improving the overall strength, antibacterial properties, air permeability and durability of the non-woven fabric.

[0089] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A high air permeability SMMS non-woven fabric, consisting of a spunbond layer, a meltblown layer and a spunbond layer, characterized in that: The raw materials of the spunbond layer include, by weight: 80-90 parts of polypropylene, 35-40 parts of ethylene-vinyl acetate copolymer, 20-23 parts of modified coconut shell fiber, 15-18 parts of seaweed extract, 10-13 parts of titanium dioxide, 9-12 parts of nano zinc oxide, 2-3 parts of maleic anhydride grafted polypropylene, 6-8 parts of polyethylene glycol, 3-5 parts of titanate coupling agent and 1-3 parts of micropore forming auxiliary agent.

2. The high air permeability SMMS nonwoven fabric according to claim 1, characterized in that: The preparation method of the modified coconut shell fiber comprises the following steps: (1) placing coconut shell fiber in a NaOH solution, stirring for 1-2 hours, washing with water, drying, and then dispersing in deionized water, adding cocamidopropyl betaine, stirring at a temperature of 40-45°C for 1-2 hours, filtering, and drying to obtain pretreated coconut shell fiber; (2) dispersing the modified carbon black in deionized water, ultrasonically treating the water at a temperature of 60-65° C. for 1-2 h, adding the pretreated coconut shell fiber of step (1), continuing ultrasonication for 2-3 h, filtering, and drying to obtain a mixture; (3) spraying the mixture of step (2) with an aqueous solution of seaweed gel, and drying the mixture to obtain modified coconut shell fiber.

3. The high air permeability SMMS nonwoven fabric according to claim 2, characterized in that: The mass ratio of the coconut shell fiber, the modified carbon black and the alginate aqueous solution is 1:0.4-0.6:0.08-0.

09.

4. The high air permeability SMMS nonwoven fabric according to claim 2, characterized in that: The preparation method of modified carbon black comprises the following steps: placing carbon black in a sodium hydroxide solution for immersion, ultrasonicating for 10-15 minutes, the ultrasonic frequency being 20-22kHz, washing with water after the ultrasonication, drying, and then ball milling, the ball milling time being 20-22 minutes, the ball milling temperature being 50-55°C, the ball milling speed being 200-210rpm, and drying after the ball milling to obtain treated carbon black; dispersing the treated carbon black in deionized water, adding nano silver particles, lignin and sodium dodecylbenzene sulfonate, stirring at a temperature of 70-75°C for 1-2 hours, and drying to obtain modified carbon black.

5. The high air permeability SMMS nonwoven fabric according to claim 1, characterized in that: The preparation method of the seaweed extract comprises the following steps: (1) removing sediment from seaweed, cutting into blocks, freezing, and crushing into small particles, dispersing the particles in methanol, stirring them fully, performing ultrasonic extraction and filtering to obtain a filtrate, and evaporating the filtrate to obtain a primary seaweed extract; (2) dispersing the primary seaweed extract of step (1) in methanol, stirring at 110-120° C., heating under reflux for 3-5 h, and centrifuging to obtain a supernatant; (3) The supernatant of step (2) is evaporated to dryness to obtain a fine seaweed extract, the fine seaweed extract is dispersed in deionized water, nano-silicon dioxide, sodium sulfate and modified starch are added, stirred at a temperature of 70-75° C. for 1-2 hours, dried, and ground to obtain a seaweed extract.

6. The high air permeability SMMS nonwoven fabric according to claim 5, characterized in that: The mass ratio of the seaweed primary extract, nano silicon dioxide and modified starch is 1:0.7-0.8:0.3-0.

5.

7. The high air permeability SMMS nonwoven fabric according to claim 5, characterized in that: The preparation method of the modified starch comprises the following steps: grinding corn starch until the particle size passes the sieve, then dispersing the corn starch in a sodium hydroxide solution, stirring the solution at a temperature of 55-60°C for 6-8h, centrifuging, removing the supernatant, filtering and drying to obtain pretreated starch, dispersing the pretreated starch in deionized water, adding chitosan fiber and gelatin, stirring the solution at a temperature of 70-75°C for 1-2h, and drying to obtain the modified starch.

8. The high air permeability SMMS nonwoven fabric according to claim 1, characterized in that: The preparation method of the melt-blown layer comprises the following steps: drying the raw materials of the melt-blown layer, extruding and spinning them into fibers, forming a mesh surface, and solidifying them to obtain the melt-blown layer.

9. The high air permeability SMMS nonwoven fabric according to claim 1, characterized in that: The raw material of the melt-blown layer is composed of 90-95% of melt-blown special masterbatch and 5-10% of high hydrostatic pressure masterbatch according to weight percentage.

10. The method for preparing a high air permeability SMMS non-woven fabric according to claim 1, characterized in that: The method comprises the following steps: uniformly mixing polypropylene, ethylene-vinyl acetate copolymer, modified coconut shell fiber, seaweed extract, titanium dioxide, nano zinc oxide, polyethylene glycol, maleic anhydride grafted polypropylene, titanate coupling agent and micropore forming auxiliary agent, and forming a primary fiber web through melt extrusion, spinning, stretching and web forming; and then obtaining a spunbond layer through pre-curing and main curing treatment; The spunbond layer, the meltblown layer and the spunbond layer are compounded at a compounding temperature of 145-150° C. and a pressure of 50-55 KPa to obtain a high air permeability SMMS non-woven fabric.

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