High-strength waterproof composite non-woven fabric and preparation method thereof

Abstract

The invention relates to the technical field of polymer composite materials, and particularly discloses a high-strength waterproof composite non-woven fabric and a preparation method thereof.The high-strength waterproof composite non-woven fabric is a double-layer co-extrusion composite non-woven fabric and comprises a non-woven fabric layer and a waterproof layer, and the non-woven fabric layer comprises raw materials including a high-melting-point polymer and a low-melting-point polymer; the waterproof layer is prepared from the following raw materials: polybutylene-1, modified ethylene propylene rubber, an interface modifier, talcum powder, titanium dioxide, an ultraviolet light absorber and an antioxidant. By introducing the interface modifier containing the isocyanate group and the epoxy group, the technical problem that the interface between the non-polar rubber-based waterproof layer and the polar polyester-based enhancement layer is incompatible is effectively solved; active groups of the interface modifier and active groups on the surface of the non-woven fabric layer form covalent bonds, and a polypropylene main chain of the interface modifier and a waterproof layer matrix form physical entanglement through chain segment movement, so that high interlayer peeling strength is macroscopically shown.

Description

Technical Field

[0001] This invention relates to the field of polymer composite materials technology, specifically to a high-strength waterproof composite nonwoven fabric and its preparation method. Background Technology

[0002] Composite nonwoven fabrics, combining the advantages of different materials, have wide applications in building waterproofing, geosynthetics, and protective equipment. Currently, the mainstream processes for preparing waterproof composite nonwoven fabrics include lamination, hot melt adhesive lamination, and co-extrusion composite spinning.

[0003] The coating and lamination methods involve hot-pressing a pre-fabricated waterproof membrane or hot-melt adhesive layer onto a non-woven fabric. The limitation of these processes is that the bonding between the waterproof layer and the non-woven fabric layer relies primarily on physical adhesion or the mechanical anchoring effect of the adhesive, resulting in limited interfacial bonding strength. During long-term use, factors such as changes in environmental temperature and humidity, and mechanical stress can cause the adhesive to age and degrade, leading to delamination and wrinkling of the composite material, ultimately compromising the integrity of the waterproof layer and causing waterproofing failure.

[0004] Co-extrusion composite spinning refers to the process of combining functional polymer melts used to form different layers within a single die and extruding them through a composite spinneret to form composite fibers with an integrated interlayer structure. This fundamentally avoids the aging problems associated with adhesives and effectively solves the problem of insufficient interfacial bonding in composite nonwoven fabrics. However, current technologies often use polypropylene (PP) spunbond nonwoven fabric as the reinforcing layer. The tensile strength and modulus of polypropylene fibers have inherent upper limits, making it difficult for the overall strength, creep resistance, and dimensional stability of the final composite material to meet the requirements of high-load applications such as high-grade building roof waterproofing and large-scale water conservancy project seepage prevention. Furthermore, existing waterproofing layer materials typically use general-purpose polyolefins such as polyethylene (PE) and polypropylene (PP). When unmodified, the macromolecular chain structure of these materials is sensitive to ultraviolet radiation and thermo-oxidative environments. Long-term exposure to the outdoors will cause degradation, embrittlement, and cracking, leading to a significant decrease in waterproofing performance over time.

[0005] To improve the mechanical properties and durability of composite materials, existing technologies attempt to co-extrude high-strength polyester (PET) as a reinforcing layer with an ethylene propylene diene monomer (EPDM)-based waterproof layer, which possesses excellent elasticity and weather resistance. However, PET is a highly polar polymer, while EPDM is a non-polar polymer. The significant difference in polarity and surface energy between the two leads to extremely poor interfacial compatibility, making it impossible to form effective interlayer bonding during co-extrusion, resulting in a high likelihood of delamination in the composite product. Therefore, there is an urgent need in the field to develop a technical solution that can solve the interfacial compatibility problem between the high-strength polyester-based nonwoven fabric layer and the highly elastic, weather-resistant waterproof layer in the co-extrusion process, and synergistically optimize the overall mechanical properties and long-term waterproof durability of the composite material. Based on the above, this invention proposes a high-strength waterproof composite nonwoven fabric and its preparation method. Summary of the Invention

[0006] To address the technical problems in existing technologies, such as insufficient overall strength of composite nonwoven fabrics, poor weather resistance of waterproof layer materials, unstable long-term waterproof performance, and poor interfacial compatibility between high-strength polar nonwoven fabric layers and non-polar waterproof layers, making it difficult to form a stable bond, this invention proposes a high-strength waterproof composite nonwoven fabric and its preparation method.

[0007] In a first aspect, the present invention provides a high-strength waterproof composite nonwoven fabric, which adopts the following technical solution:

[0008] A high-strength waterproof composite nonwoven fabric, wherein the composite nonwoven fabric is a double-layer co-extruded composite nonwoven fabric, comprising a nonwoven fabric layer and a waterproof layer, wherein the weight ratio of the nonwoven fabric layer to the waterproof layer is 1-3:4-7.

[0009] The nonwoven fabric layer comprises the following raw materials in parts by weight: 60-80 parts of high melting point polymer and 20-40 parts of low melting point polymer;

[0010] The waterproof layer comprises the following raw materials in parts by weight: 30-50 parts of polybutene-1, 20-40 parts of modified ethylene propylene rubber, 2-8 parts of interface modifier, 10-20 parts of talc, 3-8 parts of titanium dioxide, 0.5-1.5 parts of ultraviolet absorber, and 0.5-1.5 parts of antioxidant.

[0011] The modified ethylene propylene rubber is obtained by reacting ethylene propylene rubber with allyl polyether, vinyltrimethoxysilane and polymethylhydrosiloxane in sequence under the action of a platinum catalyst.

[0012] Preferably, the high-melting-point polymer in the nonwoven fabric layer is polyethylene terephthalate (PET), with a melting point of 245-265℃ and an intrinsic viscosity of 0.70 dL / g-0.90 dL / g. Using PET with high intrinsic viscosity as the fiber skeleton ensures that the nonwoven fabric layer has high initial modulus and tensile strength.

[0013] Preferably, the low-melting-point polymer in the nonwoven fabric layer is hydrogenated rosin glycerol ester, with a softening point of 80-120℃ and a hydroxyl value of not less than 5 mgKOH / g. The low-melting-point component melts during hot rolling and acts as a binder for the PET fibers; the hydroxyl groups (-OH) retained in its molecular structure provide active sites for subsequent chemical reactions with the interface modifier.

[0014] Preferably, the method for preparing the modified ethylene propylene rubber in the waterproof layer includes the following steps:

[0015] S1. Ethylene propylene rubber is put into a high-temperature internal mixer and melted and plasticized for 3-5 minutes to obtain ethylene propylene rubber melt;

[0016] S2. Add allyl polyether and vinyltrimethoxysilane sequentially to the ethylene propylene rubber melt, and mix for 4-8 minutes to obtain an intermediate mixture;

[0017] S3. Add polymethylhydrosiloxane to the intermediate mixture, mix for 1-2 minutes, then add platinum catalyst dropwise, raise the system temperature to 170-180℃, and knead for 5-10 minutes to obtain modified ethylene propylene rubber material;

[0018] S4. Compress the modified ethylene propylene rubber material into sheets, cool, and pelletize to obtain modified ethylene propylene rubber.

[0019] In the preparation of modified ethylene propylene rubber, pre-grafting of allyl polyether and vinyltrimethoxysilane provides uniformly distributed reaction sites for the subsequent hydrosilylation reaction of polymethylhydrosiloxane and the hydrolysis-condensation reaction of vinyltrimethoxysilane. These two reactions work synergistically to construct a uniform and dense three-dimensional siloxane (Si-O-Si) crosslinked network in situ within the ethylene propylene rubber matrix. This network structure not only acts as a reinforcing skeleton, significantly improving the tensile and tear strength of the material, but also endows it with excellent hydrophobicity and extremely low water absorption, thus achieving excellent mechanical strength and waterproof sealing performance.

[0020] Preferably, the parameters of the high-temperature internal mixer in S1 are set as follows: temperature 160-170℃, rotor speed 40-60rpm.

[0021] Preferably, the mass ratio of ethylene propylene rubber melt, allyl polyether, and vinyltrimethoxysilane in S2 is 100:8-15:2-4.

[0022] Preferably, the mass ratio of polymethylhydrosiloxane to the intermediate mixture in S3 is 1-5:110-119.

[0023] Preferably, the platinum catalyst in S3 is a cassiterite catalyst, and the final content of active platinum (Pt) in the system reaches 5-20 ppm.

[0024] Preferably, the interface modifier in the waterproof layer is polypropylene co-grafted with glycidyl methacrylate (GMA) and m-isopropenyl-α,α'-dimethylbenzyl isocyanate (TMI).

[0025] Preferably, the interface modifier in the waterproof layer is prepared by the following method:

[0026] (1) Polypropylene and antioxidant 1076 are initially mixed in a mixer to obtain a solid mixture; glycidyl methacrylate, m-isopropenyl-α,α'-dimethylbenzyl isocyanate and initiator are premixed to obtain a liquid mixture;

[0027] (2) The solid mixture is added to the twin-screw extruder. In the liquid injection zone, the liquid mixture is injected into the molten solid mixture by a high-pressure metering pump to carry out the melt grafting reaction and obtain the reacted melt.

[0028] (3) The reacted melt is extruded, cooled, dried, and granulated, and then heated and dried under vacuum to obtain the interface modifier.

[0029] Preferably, the mass ratio of polypropylene, antioxidant 1076, glycidyl methacrylate, m-isopropenyl-α,α'-dimethylbenzyl isocyanate and initiator in (1) is 100:0.1-0.5:2-8:1-5:0.1-0.5.

[0030] This invention grafts GMA monomers with active epoxy groups and TMI monomers with active isocyanate groups onto a polypropylene macromolecular chain simultaneously under the action of an initiator. During co-extrusion compounding and hot rolling, the epoxy groups (-NCO) on the macromolecular chain of this interface modifier react with the hydroxyl groups (-OH) of hydrogenated rosin glycerol esters in the nonwoven fabric layer, while the epoxy groups undergo ring-opening reactions with the carboxyl or hydroxyl groups at the ends of the PET fibers. Simultaneously, the polypropylene backbone exhibits good physical compatibility with the polybutene-1 and EPDM matrix in the waterproof layer, thereby constructing a dense interface layer between the two layers that combines chemical bonding and physical entanglement.

[0031] Preferably, the initiator in (1) is dicumyl peroxide.

[0032] Preferably, in the (2) twin-screw extruder, the length-to-diameter ratio L / D is ≥40, and the temperature of each zone is set as follows: feeding zone 60℃, compression zone 170℃, liquid injection zone 185℃, reaction zone 210℃, homogenization zone 200℃, and die 190℃; the screw speed is controlled at 200-400 rpm to ensure that the material has sufficient shearing and reaction residence time.

[0033] Preferably, the ultraviolet absorber is 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol.

[0034] Preferably, the antioxidant is a mixture of antioxidant 1010 and antioxidant 168.

[0035] Preferably, the antioxidant is antioxidant 1010 and antioxidant 168 in a mass ratio of 1:2.

[0036] Secondly, the present invention provides a method for preparing a high-strength waterproof composite nonwoven fabric, which adopts the following technical solution:

[0037] A method for preparing a high-strength waterproof composite nonwoven fabric includes the following steps:

[0038] Step 1: By weight, dry the high-melting-point polymer and the low-melting-point polymer under vacuum conditions and mix them evenly to obtain the nonwoven fabric layer feed; dry the polybutene-1, modified ethylene propylene rubber, interface modifier, talc, titanium dioxide, ultraviolet absorber and antioxidant under vacuum conditions and mix them, then melt-blend and pelletize them through a twin-screw extruder to obtain the waterproof layer feed;

[0039] Step 2: The non-woven fabric layer feed and the waterproof layer feed are added to two extruders for plasticization and melting, compounded through a co-extrusion die, and co-extruded through the composite spinneret holes on the spinneret to obtain co-extruded composite filaments;

[0040] Step 3: The co-extruded composite filaments are cooled and shaped in the side-blowing cooling zone, and then blown onto the forming screen under the action of airflow to obtain a composite fiber web;

[0041] Step 4: The composite fiber web is fed into a hot rolling mill for hot pressing and bonding. After hot rolling, the nonwoven fabric is cooled, trimmed, and rolled up to obtain a high-strength waterproof composite nonwoven fabric.

[0042] Preferably, in step 1, the length-to-diameter ratio (L / D) of the twin-screw extruder is ≥40, the screw speed is controlled at 250-300 rpm, and the temperatures of each zone are set as follows: feeding zone 140℃, plasticizing zone 150℃, blending zone 170℃, homogenizing zone 175℃, and die head 170℃.

[0043] Preferably, in step 2, the length-to-diameter ratio (L / D) of the twin-screw extruder through which the nonwoven fabric layer is fed is ≥40, the screw speed is controlled at 100-120 rpm, and the temperatures of each zone are set as follows: feeding zone 180℃, compression zone 210℃, metering zone 230℃, and die head 235℃.

[0044] Preferably, in step 2, the length-to-diameter ratio (L / D) of the twin-screw extruder through which the waterproof layer is fed is ≥40, the screw speed is controlled at 20-30 rpm, and the temperatures of each zone are set as follows: feeding zone 160℃, compression zone 180℃, metering zone 195℃, and die head 200℃.

[0045] Preferably, in step 3, the wind speed in the side-blowing cooling zone is 0.5-1.0 m / s, and the temperature is 25-35℃.

[0046] Preferably, in step 4, the surface temperature of both the upper and lower rolls of the hot rolling mill is set to 140-150℃, and the linear pressure between the rolls is 68-72N / mm.

[0047] In summary, the present invention has the following beneficial effects:

[0048] 1. This invention significantly improves the overall mechanical properties of the composite material by using high intrinsic viscosity PET as the skeleton material for the nonwoven fabric layer and combining it with a modified EPDM waterproof layer. Simultaneously, by introducing an interface modifier containing dual active functional groups, a chemically bonded interface is constructed between the polar nonwoven fabric layer and the non-polar waterproof layer, ensuring high peel strength (up to 5N / 25mm or more) between the two layers. This strong interlayer bonding allows the two layers to work together to bear loads under stress, effectively inhibiting interlayer slippage and delamination, and ensuring the structural integrity of the composite material under high stress.

[0049] 2. The waterproof layer of this invention adopts a blend system of polybutene-1 and modified ethylene propylene rubber. The three-dimensional siloxane cross-linked network structure formed inside the modified ethylene propylene rubber significantly improves the cross-linking density and heat and weather resistance of the ethylene propylene rubber, effectively inhibiting the aging and degradation of the composite material under the action of heat, oxygen, and ultraviolet light. The composite nonwoven fabric prepared by this invention has excellent waterproof performance (resistance to hydrostatic pressure exceeding 6000 mmH2O). After 200 hours of accelerated aging under a xenon lamp, its tensile strength retention rate is still above 85%, demonstrating excellent weather resistance and long-term waterproof reliability.

[0050] 3. In the modified ethylene propylene rubber preparation method of the present invention, the uniformity and integrity of the crosslinking network are ensured by adding reactants in a specific order. At the same time, the present invention effectively solves the technical problem of interfacial incompatibility between the non-polar rubber-based waterproof layer and the polar polyester-based reinforcing layer by introducing an interface modifier containing isocyanate groups and epoxy groups. The active groups of the interface modifier form covalent bonds with the active groups on the surface of the nonwoven fabric layer, while its polypropylene backbone forms physical entanglement with the waterproof layer matrix through chain segment movement, thus exhibiting high interlayer peel strength on a macroscopic scale. Detailed Implementation

[0051] The present invention will be further described in detail below with reference to the embodiments.

[0052] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0053] The key raw materials used in this invention are sourced from the following sources:

[0054] Polyethylene terephthalate: CAS No. 25038-59-9, purchased from Shanghai Maclean Biochemical Technology Co., Ltd.;

[0055] Hydrogenated rosin glyceryl ester: CAS No. 65997-13-9, purchased from Hubei Great Biomedical Technology Co., Ltd.;

[0056] Ethylene propylene rubber: CAS No. 25038-36-2, purchased from Shanghai Hehongcheng Plastics Technology Co., Ltd.;

[0057] Allyl polyether: Product code APEG, purchased from Haian Petrochemical Plant, Jiangsu Province;

[0058] Vinyltrimethoxysilane: Product No. KH-171, purchased from Hangzhou Jessica Chemical Co., Ltd.;

[0059] Polymethylhydrosiloxane: Product No. Y17980, purchased from Shanghai Yuanye Biotechnology Co., Ltd.;

[0060] Castel catalyst: CAS No. 68478-92-2, model llb68478, purchased from Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.;

[0061] Glycidyl methacrylate: Product No. G106686, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0062] m-Isopropenyl-α,α'-dimethylbenzyl isocyanate: CAS No. 2094-99-7, purchased from Shanghai Jizhi Biochemical Technology Co., Ltd.;

[0063] Polypropylene: CAS No. 9003-07-0, purchased from Shanghai Maclean Biochemical Technology Co., Ltd.;

[0064] Talc powder: CAS14807-96-6, fineness 1250 mesh, purchased from Shijiazhuang Tourmaline Mineral Products Co., Ltd.

[0065] Titanium dioxide: CAS No. 13463-67-7, purchased from Jinan Hongquan Titanium Industry Co., Ltd.;

[0066] Antioxidant 1076: Product number CRM00318-100MG, purchased from MeRck;

[0067] Dicumyl peroxide: Product No. 329541, purchased from MeRck;

[0068] 2-(4,6-Diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol: CAS No. 106556-36-9, purchased from Zhengzhou Alpha Chemical Co., Ltd.;

[0069] Antioxidant 1010 (CAS No. 6683-19-8) and Antioxidant 168 (CAS No. 31570-04-4) were both purchased from Jinan Hongteng Weiye New Materials Co., Ltd.

[0070] Preparation Examples 1-3 and Comparative Preparation Example 1-2 provide methods for preparing modified ethylene propylene rubber.

[0071] Preparation Example 1

[0072] The preparation method of modified ethylene propylene rubber includes the following steps:

[0073] S1. Ethylene propylene rubber is placed in a high-temperature internal mixer at a temperature of 160℃ and a speed of 40rpm. After melting and plasticizing for 3 minutes, ethylene propylene rubber melt is obtained.

[0074] S2. Control the mass ratio of ethylene propylene rubber melt, allyl polyether and vinyltrimethoxysilane to 100:8:2, keep the temperature and speed of the high-temperature internal mixer constant, add allyl polyether and vinyltrimethoxysilane to the ethylene propylene rubber melt in sequence, and after internal mixing for 4 minutes, obtain an intermediate mixture.

[0075] S3. Control the mass ratio of polymethylhydrosiloxane to intermediate mixture to 1:110. Add polymethylhydrosiloxane to intermediate mixture and mix for 1 min. Then, add caster catalyst at a rate of 3 mL / min (final active platinum content in system is 5 ppm). Then raise the system temperature to 170℃ and knead for 5 min to obtain modified ethylene propylene rubber material.

[0076] S4. The modified ethylene propylene rubber material is transferred to a tablet press and pressed into thin sheets. After being cooled by air via a conveyor belt, it is cold-cut into pellets to obtain modified ethylene propylene rubber.

[0077] Preparation Example 2

[0078] The preparation method of modified ethylene propylene rubber includes the following steps:

[0079] S1. Ethylene propylene rubber is placed in a high-temperature internal mixer at 165℃ and 50rpm, and after melting and plasticizing for 4 minutes, ethylene propylene rubber melt is obtained.

[0080] S2. Control the mass ratio of ethylene propylene rubber melt, allyl polyether and vinyltrimethoxysilane to 100:10:3, keep the temperature and speed of the high-temperature internal mixer constant, add allyl polyether and vinyltrimethoxysilane to the ethylene propylene rubber melt in sequence, and after internal mixing for 6 minutes, obtain an intermediate mixture.

[0081] S3. Control the mass ratio of polymethylhydrosiloxane and intermediate mixture to 3:113. Add polymethylhydrosiloxane to intermediate mixture and mix for 1.5 min. Then, add caster catalyst (the final content of active platinum element in the system is 10 ppm) dropwise at a rate of 3.5 mL / min. Then, raise the system temperature to 175℃ and knead for 8 min to obtain modified ethylene propylene rubber material.

[0082] S4. The modified ethylene propylene rubber material is transferred to a tablet press and pressed into thin sheets. After being cooled by air via a conveyor belt, it is cold-cut into pellets to obtain modified ethylene propylene rubber.

[0083] Preparation Example 3

[0084] The preparation method of modified ethylene propylene rubber includes the following steps:

[0085] S1. Ethylene propylene rubber is placed in a high-temperature internal mixer at a temperature of 170℃ and a speed of 60rpm, and after melting and plasticizing for 5 minutes, ethylene propylene rubber melt is obtained.

[0086] S2. Control the mass ratio of ethylene propylene rubber melt, allyl polyether and vinyltrimethoxysilane to 100:15:4, keep the temperature and speed of the high-temperature internal mixer constant, add allyl polyether and vinyltrimethoxysilane to the ethylene propylene rubber melt in sequence, and after internal mixing for 8 minutes, obtain an intermediate mixture.

[0087] S3. Control the mass ratio of polymethylhydrosiloxane and intermediate mixture to 5:119. Add polymethylhydrosiloxane to intermediate mixture and mix for 2 min. Then, add caster catalyst at a rate of 4 mL / min (the final content of active platinum element in the system is 20 ppm). Then, raise the system temperature to 180℃ and knead for 10 min to obtain modified ethylene propylene rubber material.

[0088] S4. The modified ethylene propylene rubber material is transferred to a tablet press and pressed into thin sheets. After being cooled by air via a conveyor belt, it is cold-cut into pellets to obtain modified ethylene propylene rubber.

[0089] Comparative Preparation Example 1

[0090] The preparation method of modified ethylene propylene rubber includes the following steps:

[0091] S1. Ethylene propylene rubber is placed in a high-temperature internal mixer at a temperature of 160℃ and a speed of 40rpm. After melting and plasticizing for 3 minutes, ethylene propylene rubber melt is obtained.

[0092] S2. Control the mass ratio of ethylene propylene rubber melt to allyl polyether to be 100:10, keep the temperature and speed of the high-temperature internal mixer constant, add allyl polyether to the ethylene propylene rubber melt, and after internal mixing for 4 minutes, obtain an intermediate mixture.

[0093] S3. Control the mass ratio of polymethylhydrosiloxane to intermediate mixture to 1:110. Add polymethylhydrosiloxane to intermediate mixture and mix for 1 min. Then, add caster catalyst at a rate of 3 mL / min (final active platinum content in system is 5 ppm). Then raise the system temperature to 170℃ and knead for 5 min to obtain modified ethylene propylene rubber material.

[0094] S4. The modified ethylene propylene rubber material is transferred to a tablet press and pressed into thin sheets. After being cooled by air via a conveyor belt, it is cold-cut into pellets to obtain modified ethylene propylene rubber.

[0095] Comparative Preparation Example 2

[0096] The preparation method of modified ethylene propylene rubber includes the following steps:

[0097] S1. Ethylene propylene rubber is placed in a high-temperature internal mixer at a temperature of 160℃ and a speed of 40rpm. After melting and plasticizing for 3 minutes, ethylene propylene rubber melt is obtained.

[0098] S2. Control the mass ratio of ethylene propylene rubber melt to vinyltrimethoxysilane to be 100:10, keep the temperature and speed of the high-temperature internal mixer constant, add vinyltrimethoxysilane to the ethylene propylene rubber melt, and after internal mixing for 4 minutes, obtain an intermediate mixture;

[0099] S3. Control the mass ratio of polymethylhydrosiloxane to intermediate mixture to 1:110. Add polymethylhydrosiloxane to intermediate mixture and mix for 1 min. Then, add caster catalyst at a rate of 3 mL / min (final active platinum content in system is 5 ppm). Then raise the system temperature to 170℃ and knead for 5 min to obtain modified ethylene propylene rubber material.

[0100] S4. The modified ethylene propylene rubber material is transferred to a tablet press and pressed into thin sheets. After being cooled by air via a conveyor belt, it is cold-cut into pellets to obtain modified ethylene propylene rubber.

[0101] Comparative preparation example 3

[0102] The preparation method of modified ethylene propylene rubber includes the following steps:

[0103] S1. Ethylene propylene rubber is placed in a high-temperature internal mixer at a temperature of 160℃ and a speed of 40rpm. After melting and plasticizing for 3 minutes, ethylene propylene rubber melt is obtained.

[0104] S2. Control the mass ratio of ethylene propylene rubber melt, allyl polyether, polymethylhydrosiloxane and vinyltrimethoxysilane to 100:8:1:2. Keep the temperature and speed of the high-temperature internal mixer constant. Add allyl polyether to the ethylene propylene rubber melt and mix for 4 minutes. Then add polymethylhydrosiloxane and mix for 1 minute. Finally add vinyltrimethoxysilane and mix for 4 minutes to obtain an intermediate mixture.

[0105] S3. Add the Castel catalyst (the final content of active platinum in the system is 5 ppm) dropwise to the intermediate mixture at a rate of 3 mL / min, then raise the system temperature to 170℃ and knead for 5 min to obtain the modified ethylene propylene rubber material.

[0106] S4. The modified ethylene propylene rubber material is transferred to a tablet press and pressed into thin sheets. After being cooled by air via a conveyor belt, it is cold-cut into pellets to obtain modified ethylene propylene rubber.

[0107] Comparative preparation example 4

[0108] The preparation method of modified ethylene propylene rubber includes the following steps:

[0109] S1. Ethylene propylene rubber is placed in a high-temperature internal mixer at a temperature of 160℃ and a speed of 40rpm. After melting and plasticizing for 3 minutes, ethylene propylene rubber melt is obtained.

[0110] S2. Control the mass ratio of ethylene propylene rubber melt, allyl polyether and vinyltrimethoxysilane to 100:8:2, keep the temperature and speed of the high-temperature internal mixer constant, add vinyltrimethoxysilane to the ethylene propylene rubber melt and mix for 4 min, then add allyl polyether and mix for 4 min to obtain an intermediate mixture.

[0111] S3. Control the mass ratio of polymethylhydrosiloxane to intermediate mixture to 1:110. Add polymethylhydrosiloxane to intermediate mixture and mix for 1 min. Then, add caster catalyst at a rate of 3 mL / min (final active platinum content in system is 5 ppm). Then raise the system temperature to 170℃ and knead for 5 min to obtain modified ethylene propylene rubber material.

[0112] S4. The modified ethylene propylene rubber material is transferred to a tablet press and pressed into thin sheets. After being cooled by air via a conveyor belt, it is cold-cut into pellets to obtain modified ethylene propylene rubber.

[0113] Preparation Examples 4-6 and Comparative Preparation Examples 5-6 provide methods for preparing interface modifiers.

[0114] Preparation Example 4

[0115] The interface modifier is prepared by the following method:

[0116] (1) The mass ratio of polypropylene, antioxidant 1076, glycidyl methacrylate, m-isopropenyl-α,α'-dimethylbenzyl isocyanate and dicumyl peroxide is controlled to be 100:0.1:2:1:0.1. Polypropylene and antioxidant 1076 are initially mixed in a mixer to obtain a solid mixture. Glycidyl methacrylate, m-isopropenyl-α,α'-dimethylbenzyl isocyanate and initiator are premixed to obtain a liquid mixture.

[0117] (2) Add the solid mixture into a twin-screw extruder (length-to-diameter ratio L / D=40), control the screw speed at 200 rpm, and set the temperature of each zone as follows: feeding zone 60℃, compression zone 170℃, liquid injection zone 185℃, reaction zone 210℃, homogenization zone 200℃, and die 190℃. In the liquid injection zone, inject the liquid mixture into the molten solid mixture through a high-pressure metering pump to carry out the melt grafting reaction and obtain the melt after reaction.

[0118] (3) The melt after reaction is extruded into strips through a die, cooled in a water tank and dried, then granulated. The granules are placed in a vacuum oven at 85°C and dried for 8 hours to obtain an interface modifier.

[0119] Preparation Example 5

[0120] The interface modifier is prepared by the following method:

[0121] (1) The mass ratio of polypropylene, antioxidant 1076, glycidyl methacrylate, m-isopropenyl-α,α'-dimethylbenzyl isocyanate and dicumyl peroxide is controlled to be 100:0.2:6:3:0.2. Polypropylene and antioxidant 1076 are initially mixed in a mixer to obtain a solid mixture. Glycidyl methacrylate, m-isopropenyl-α,α'-dimethylbenzyl isocyanate and initiator are premixed to obtain a liquid mixture.

[0122] (2) Add the solid mixture into a twin-screw extruder (length-to-diameter ratio L / D=40), control the screw speed at 300 rpm, and set the temperature of each zone as follows: feeding zone 60℃, compression zone 170℃, liquid injection zone 185℃, reaction zone 210℃, homogenization zone 200℃, and die 190℃. In the liquid injection zone, inject the liquid mixture into the molten solid mixture through a high-pressure metering pump to carry out the melt grafting reaction and obtain the reacted melt.

[0123] (3) The melt after reaction is extruded into strips through a die, cooled in a water tank and dried, then granulated. The granules are placed in a vacuum oven at 85°C and dried for 8 hours to obtain an interface modifier.

[0124] Preparation Example 6

[0125] The interface modifier is prepared by the following method:

[0126] (1) The mass ratio of polypropylene, antioxidant 1076, glycidyl methacrylate, m-isopropenyl-α,α'-dimethylbenzyl isocyanate and dicumyl peroxide is controlled to be 100:0.5:8:5:0.5. Polypropylene and antioxidant 1076 are initially mixed in a mixer to obtain a solid mixture. Glycidyl methacrylate, m-isopropenyl-α,α'-dimethylbenzyl isocyanate and initiator are premixed to obtain a liquid mixture.

[0127] (2) Add the solid mixture into a twin-screw extruder (length-to-diameter ratio L / D=40), control the screw speed at 400 rpm, and set the temperature of each zone as follows: feeding zone 60℃, compression zone 170℃, liquid injection zone 185℃, reaction zone 210℃, homogenization zone 200℃, and die 190℃. In the liquid injection zone, inject the liquid mixture into the molten solid mixture through a high-pressure metering pump to carry out the melt grafting reaction and obtain the melt after reaction.

[0128] (3) The melt after reaction is extruded into strips through a die, cooled in a water tank and dried, then granulated. The granules are placed in a vacuum oven at 85°C and dried for 8 hours to obtain an interface modifier.

[0129] Comparative preparation example 5

[0130] The interface modifier is prepared by the following method:

[0131] (1) The mass ratio of polypropylene, antioxidant 1076, glycidyl methacrylate and dicumyl peroxide is controlled to be 100:0.1:3:0.1. Polypropylene and antioxidant 1076 are initially mixed in a mixer to obtain a solid mixture; glycidyl methacrylate and initiator are premixed to obtain a liquid mixture.

[0132] (2) Add the solid mixture into a twin-screw extruder (length-to-diameter ratio L / D=40), control the screw speed at 200 rpm, and set the temperature of each zone as follows: feeding zone 60℃, compression zone 170℃, liquid injection zone 185℃, reaction zone 210℃, homogenization zone 200℃, and die 190℃. In the liquid injection zone, inject the liquid mixture into the molten solid mixture through a high-pressure metering pump to carry out the melt grafting reaction and obtain the melt after reaction.

[0133] (3) The melt after reaction is extruded into strips through a die, cooled in a water tank and dried, then granulated. The granules are placed in a vacuum oven at 85°C and dried for 8 hours to obtain an interface modifier.

[0134] Comparative preparation example 6

[0135] The interface modifier is prepared by the following method:

[0136] (1) The mass ratio of polypropylene, antioxidant 1076, m-isopropenyl-α,α'-dimethylbenzyl isocyanate and dicumyl peroxide is controlled to be 100:0.1:3:0.1. Polypropylene and antioxidant 1076 are initially mixed in a mixer to obtain a solid mixture; m-isopropenyl-α,α'-dimethylbenzyl isocyanate and initiator are premixed to obtain a liquid mixture.

[0137] (2) Add the solid mixture into a twin-screw extruder (length-to-diameter ratio L / D=40), control the screw speed at 200 rpm, and set the temperature of each zone as follows: feeding zone 60℃, compression zone 170℃, liquid injection zone 185℃, reaction zone 210℃, homogenization zone 200℃, and die 190℃. In the liquid injection zone, inject the liquid mixture into the molten solid mixture through a high-pressure metering pump to carry out the melt grafting reaction and obtain the melt after reaction.

[0138] (3) The melt after reaction is extruded into strips through a die, cooled in a water tank and dried, then granulated. The granules are placed in a vacuum oven at 85°C and dried for 8 hours to obtain an interface modifier.

[0139] Examples 1-3 provide a high-strength waterproof composite nonwoven fabric and its preparation method.

[0140] Example 1

[0141] A high-strength waterproof composite nonwoven fabric is a double-layer co-extruded composite nonwoven fabric, comprising a nonwoven fabric layer and a waterproof layer. The formulation and preparation method of each layer are as follows:

[0142] Step 1, Preparation of nonwoven fabric layer feed: Weigh 60 parts of polyethylene terephthalate (melting point 258℃, intrinsic viscosity 0.85dL / g) and 20 parts of hydrogenated rosin glycerol ester (softening point 100℃, hydroxyl value 6mgKOH / g). Dry each raw material at 85℃ and vacuum degree -0.08MPa for 4h, then mix them at 35rpm for 18min to obtain the nonwoven fabric layer feed;

[0143] Waterproof layer feed preparation: Weigh 30 parts of polybutene-1, 20 parts of modified ethylene propylene rubber prepared in Preparation Example 1, 2 parts of interface modifier prepared in Preparation Example 4, 10 parts of talc powder, 3 parts of titanium dioxide, 0.5 parts of 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol, and 0.5 parts of antioxidant (including antioxidant 1010 and antioxidant 168 in a mass ratio of 1:2). After the raw material is dried at 80℃ and vacuum degree -0.08MPa for 6 hours, it is mixed at 100rpm for 8 minutes and added to a twin-screw extruder (length-to-diameter ratio L / D=41). The screw speed is 250rpm. The temperature of each zone of the extruder is set as follows: feeding zone 140℃, plasticizing zone 150℃, blending zone 170℃, homogenizing zone 175℃, and die 170℃. After melt blending and granulation in the twin-screw extruder, the waterproof layer feed is obtained.

[0144] Step 2: Control the weight ratio of the nonwoven fabric layer feed and the waterproof layer feed to 1:4. Add the nonwoven fabric layer feed and the waterproof layer feed to two extruders. The extruder used for the nonwoven fabric layer feed is set with an L / D ratio of 41, a screw speed of 100 rpm, a feeding zone temperature of 180°C, a compression zone temperature of 210°C, a metering zone temperature of 230°C, and a die temperature of 235°C. The extruder used for the waterproof layer feed is set with an L / D ratio of 41, a screw speed of 20 rpm, a feeding zone temperature of 160°C, a compression zone temperature of 180°C, a metering zone temperature of 195°C, and a die temperature of 200°C. After plasticizing and melting in the extruders, the materials are compounded through a co-extrusion die and co-extruded through the compound spinneret holes on the spinneret to obtain co-extruded composite filaments.

[0145] Step 3: The co-extruded composite filaments are cooled and shaped at 35°C in a side-blowing cooling zone (wind speed of 0.5m / s), and then blown onto a web forming curtain under the action of airflow to obtain a composite fiber web;

[0146] Step 4: The composite fiber web is fed into a hot rolling mill at 145℃ and a linear pressure of 70N / mm for hot pressing and bonding. After hot rolling, the nonwoven fabric is cooled, trimmed, and rolled up to obtain a high-strength waterproof composite nonwoven fabric.

[0147] Example 2

[0148] A high-strength waterproof composite nonwoven fabric is a double-layer co-extruded composite nonwoven fabric, comprising a nonwoven fabric layer and a waterproof layer. The formulation and preparation method of each layer are as follows:

[0149] Step 1, Preparation of nonwoven fabric layer feed: Weigh 70 parts of polyethylene terephthalate (melting point 258℃, intrinsic viscosity 0.85dL / g) and 30 parts of hydrogenated rosin glycerol ester (softening point 100℃, hydroxyl value 6mgKOH / g). Dry each raw material at 85℃ and vacuum degree -0.08MPa for 4h, then mix them at 35rpm for 18min to obtain the nonwoven fabric layer feed;

[0150] Waterproof layer feed preparation: Weigh 40 parts of polybutene-1, 30 parts of modified ethylene propylene rubber prepared in Preparation Example 2, 5 parts of interface modifier prepared in Preparation Example 5, 15 parts of talc powder, 5 parts of titanium dioxide, 1.0 part of 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol, and 1.0 part of antioxidant (including antioxidant 1010 and antioxidant 168 in a mass ratio of 1:2). After the raw material is dried at 80℃ and vacuum degree -0.08MPa for 6 hours, it is mixed at 100rpm for 8 minutes and added to a twin-screw extruder (length-to-diameter ratio L / D=41). The screw speed is 280rpm. The temperature of each zone of the extruder is set as follows: feeding zone 140℃, plasticizing zone 150℃, blending zone 170℃, homogenizing zone 175℃, and die 170℃. After melt blending and granulation in the twin-screw extruder, the waterproof layer feed is obtained.

[0151] Step 2: Control the weight ratio of the nonwoven fabric layer feed and the waterproof layer feed to 2:5. Add the nonwoven fabric layer feed and the waterproof layer feed to two extruders. The extruder used for the nonwoven fabric layer feed is set with an L / D ratio of 41, a screw speed of 110 rpm, a feeding zone temperature of 180°C, a compression zone temperature of 210°C, a metering zone temperature of 230°C, and a die temperature of 235°C. The extruder used for the waterproof layer feed is set with an L / D ratio of 41, a screw speed of 25 rpm, a feeding zone temperature of 160°C, a compression zone temperature of 180°C, a metering zone temperature of 195°C, and a die temperature of 200°C. After plasticizing and melting in the extruders, the materials are compounded through a co-extrusion die and co-extruded through the compound spinneret holes on the spinneret to obtain co-extruded composite filaments.

[0152] Step 3: The co-extruded composite filaments are cooled and shaped at 30°C in the side-blowing cooling zone (wind speed of 0.8m / s), and then blown onto the web forming curtain under the action of airflow to obtain the composite fiber web;

[0153] Step 4: The composite fiber web is fed into a hot rolling mill at 145℃ and a linear pressure of 70N / mm for hot pressing and bonding. After hot rolling, the nonwoven fabric is cooled, trimmed, and rolled up to obtain a high-strength waterproof composite nonwoven fabric.

[0154] Example 3

[0155] A high-strength waterproof composite nonwoven fabric is a double-layer co-extruded composite nonwoven fabric, comprising a nonwoven fabric layer and a waterproof layer. The formulation and preparation method of each layer are as follows:

[0156] Step 1, Preparation of nonwoven fabric layer feed: Weigh 80 parts of polyethylene terephthalate (melting point 258℃, intrinsic viscosity 0.85dL / g) and 40 parts of hydrogenated rosin glycerol ester (softening point 100℃, hydroxyl value 6mgKOH / g). Dry each raw material at 85℃ and vacuum degree -0.08MPa for 4h, then mix them at 35rpm for 18min to obtain the nonwoven fabric layer feed;

[0157] Waterproof layer feed preparation: Weigh 50 parts of polybutene-1, 40 parts of modified ethylene propylene rubber prepared in Preparation Example 3, 8 parts of interface modifier prepared in Preparation Example 6, 20 parts of talc powder, 8 parts of titanium dioxide, 1.5 parts of 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol, and 1.5 parts of antioxidant (including antioxidant 1010 and antioxidant 168 in a mass ratio of 1:2). After the raw material is dried at 80℃ and vacuum degree -0.08MPa for 6 hours, it is mixed at 100rpm for 8 minutes and added to a twin-screw extruder (length-to-diameter ratio L / D=41). The screw speed is 300rpm. The temperature of each zone of the extruder is set as follows: feeding zone 140℃, plasticizing zone 150℃, blending zone 170℃, homogenizing zone 175℃, and die 170℃. After melt blending and granulation in the twin-screw extruder, the waterproof layer feed is obtained.

[0158] Step 2: Control the weight ratio of the nonwoven fabric layer feed and the waterproof layer feed to 3:7. Add the nonwoven fabric layer feed and the waterproof layer feed to two extruders. The extruder used for the nonwoven fabric layer feed is set with an L / D ratio of 41, a screw speed of 120 rpm, a feeding zone temperature of 180°C, a compression zone temperature of 210°C, a metering zone temperature of 230°C, and a die temperature of 235°C. The extruder used for the waterproof layer feed is set with an L / D ratio of 41, a screw speed of 30 rpm, a feeding zone temperature of 160°C, a compression zone temperature of 180°C, a metering zone temperature of 195°C, and a die temperature of 200°C. After plasticizing and melting in the extruders, the materials are compounded through a co-extrusion die and co-extruded through the compound spinneret holes on the spinneret plate to obtain co-extruded composite filaments.

[0159] Step 3: The co-extruded composite filaments are cooled and shaped at 25°C in the side-blowing cooling zone (wind speed of 1.0m / s), and then blown onto the forming screen under the action of airflow to obtain a composite fiber web;

[0160] Step 4: The composite fiber web is fed into a hot rolling mill at 145℃ and a linear pressure of 70N / mm for hot pressing and bonding. After hot rolling, the nonwoven fabric is cooled, trimmed, and rolled up to obtain a high-strength waterproof composite nonwoven fabric.

[0161] To verify the comprehensive performance of the high-strength waterproof composite nonwoven fabric provided by the present invention, comparative examples 1-7 were set up, wherein:

[0162] Comparative Example 1

[0163] Comparative Example 1 is the same as Example 1, except that the modified ethylene propylene rubber obtained in Preparation Example 1 is replaced with the modified ethylene propylene rubber obtained in Comparative Preparation Example 1. Specifically:

[0164] A high-strength waterproof composite nonwoven fabric is a double-layer co-extruded composite nonwoven fabric, comprising a nonwoven fabric layer and a waterproof layer. The formulation and preparation method of each layer are as follows:

[0165] Step 1, Preparation of nonwoven fabric layer feed: Weigh 60 parts of polyethylene terephthalate (melting point 258℃, intrinsic viscosity 0.85dL / g) and 20 parts of hydrogenated rosin glycerol ester (softening point 100℃, hydroxyl value 6mgKOH / g). Dry each raw material at 85℃ and vacuum degree -0.08MPa for 4h, then mix them at 35rpm for 18min to obtain the nonwoven fabric layer feed;

[0166] Waterproof layer feed preparation: Weigh 30 parts of polybutene-1, 20 parts of modified ethylene propylene rubber prepared in Comparative Preparation Example 1, 2 parts of interface modifier prepared in Preparation Example 4, 10 parts of talc powder, 3 parts of titanium dioxide, 0.5 parts of 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol, and 0.5 parts of antioxidant (including antioxidant 1010 and antioxidant 168 in a mass ratio of 1:2). After drying each raw material at 80℃ and vacuum degree -0.08MPa for 6 hours, they are mixed at 100rpm for 8 minutes and added to a twin-screw extruder (length-to-diameter ratio L / D=41). The screw speed is 250rpm. The temperature of each zone of the extruder is set as follows: feeding zone 140℃, plasticizing zone 150℃, blending zone 170℃, homogenizing zone 175℃, and die 170℃. The material is melt-blended and granulated by the twin-screw extruder to obtain the waterproof layer feed.

[0167] Step 2: Control the weight ratio of the nonwoven fabric layer feed and the waterproof layer feed to 1:4. Add the nonwoven fabric layer feed and the waterproof layer feed to two extruders. The extruder used for the nonwoven fabric layer feed is set with an L / D ratio of 41, a screw speed of 100 rpm, a feeding zone temperature of 180°C, a compression zone temperature of 210°C, a metering zone temperature of 230°C, and a die temperature of 235°C. The extruder used for the waterproof layer feed is set with an L / D ratio of 41, a screw speed of 20 rpm, a feeding zone temperature of 160°C, a compression zone temperature of 180°C, a metering zone temperature of 195°C, and a die temperature of 200°C. After plasticizing and melting in the extruders, the materials are compounded through a co-extrusion die and co-extruded through the compound spinneret holes on the spinneret to obtain co-extruded composite filaments.

[0168] Step 3: The co-extruded composite filaments are cooled and shaped at 35°C in a side-blowing cooling zone (wind speed of 0.5m / s), and then blown onto a web forming curtain under the action of airflow to obtain a composite fiber web;

[0169] Step 4: The composite fiber web is fed into a hot rolling mill at 145℃ and a linear pressure of 70N / mm for hot pressing and bonding. After hot rolling, the nonwoven fabric is cooled, trimmed, and rolled up to obtain a high-strength waterproof composite nonwoven fabric.

[0170] Comparative Example 2

[0171] Comparative Example 2 is the same as Example 1, except that the modified ethylene propylene rubber obtained in Preparation Example 1 is replaced with the modified ethylene propylene rubber obtained in Comparative Preparation Example 2. Specifically:

[0172] A high-strength waterproof composite nonwoven fabric is a double-layer co-extruded composite nonwoven fabric, comprising a nonwoven fabric layer and a waterproof layer. The formulation and preparation method of each layer are as follows:

[0173] Step 1, Preparation of nonwoven fabric layer feed: Weigh 60 parts of polyethylene terephthalate (melting point 258℃, intrinsic viscosity 0.85dL / g) and 20 parts of hydrogenated rosin glycerol ester (softening point 100℃, hydroxyl value 6mgKOH / g). Dry each raw material at 85℃ and vacuum degree -0.08MPa for 4h, then mix them at 35rpm for 18min to obtain the nonwoven fabric layer feed;

[0174] Waterproof layer feed preparation: Weigh 30 parts of polybutene-1, 20 parts of modified ethylene propylene rubber prepared in Comparative Preparation Example 2, 2 parts of interface modifier prepared in Preparation Example 4, 10 parts of talc powder, 3 parts of titanium dioxide, 0.5 parts of 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol, and 0.5 parts of antioxidant (including antioxidant 1010 and antioxidant 168 in a mass ratio of 1:2). After drying each raw material at 80℃ and vacuum degree -0.08MPa for 6 hours, they are mixed at 100rpm for 8 minutes and added to a twin-screw extruder (length-to-diameter ratio L / D=41). The screw speed is 250rpm. The temperature of each zone of the extruder is set as follows: feeding zone 140℃, plasticizing zone 150℃, blending zone 170℃, homogenizing zone 175℃, and die 170℃. The material is melt-blended and granulated by the twin-screw extruder to obtain the waterproof layer feed.

[0175] Step 2: Control the weight ratio of the nonwoven fabric layer feed and the waterproof layer feed to 1:4. Add the nonwoven fabric layer feed and the waterproof layer feed to two extruders. The extruder used for the nonwoven fabric layer feed is set with an L / D ratio of 41, a screw speed of 100 rpm, a feeding zone temperature of 180°C, a compression zone temperature of 210°C, a metering zone temperature of 230°C, and a die temperature of 235°C. The extruder used for the waterproof layer feed is set with an L / D ratio of 41, a screw speed of 20 rpm, a feeding zone temperature of 160°C, a compression zone temperature of 180°C, a metering zone temperature of 195°C, and a die temperature of 200°C. After plasticizing and melting in the extruders, the materials are compounded through a co-extrusion die and co-extruded through the compound spinneret holes on the spinneret to obtain co-extruded composite filaments.

[0176] Step 3: The co-extruded composite filaments are cooled and shaped at 35°C in a side-blowing cooling zone (wind speed of 0.5m / s), and then blown onto a web forming curtain under the action of airflow to obtain a composite fiber web;

[0177] Step 4: The composite fiber web is fed into a hot rolling mill at 145℃ and a linear pressure of 70N / mm for hot pressing and bonding. After hot rolling, the nonwoven fabric is cooled, trimmed, and rolled up to obtain a high-strength waterproof composite nonwoven fabric.

[0178] Comparative Example 3

[0179] Comparative Example 3 is the same as Example 1, except that the modified ethylene propylene rubber obtained in Preparation Example 1 is replaced with the modified ethylene propylene rubber obtained in Comparative Preparation Example 3. Specifically:

[0180] A high-strength waterproof composite nonwoven fabric is a double-layer co-extruded composite nonwoven fabric, comprising a nonwoven fabric layer and a waterproof layer. The formulation and preparation method of each layer are as follows:

[0181] Step 1, Preparation of nonwoven fabric layer feed: Weigh 60 parts of polyethylene terephthalate (melting point 258℃, intrinsic viscosity 0.85dL / g) and 20 parts of hydrogenated rosin glycerol ester (softening point 100℃, hydroxyl value 6mgKOH / g). Dry each raw material at 85℃ and vacuum degree -0.08MPa for 4h, then mix them at 35rpm for 18min to obtain the nonwoven fabric layer feed;

[0182] Waterproof layer feed preparation: Weigh 30 parts of polybutene-1, 20 parts of modified ethylene propylene rubber prepared in Comparative Preparation Example 3, 2 parts of interface modifier prepared in Preparation Example 4, 10 parts of talc powder, 3 parts of titanium dioxide, 0.5 parts of 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol, and 0.5 parts of antioxidant (including antioxidant 1010 and antioxidant 168 in a mass ratio of 1:2). After drying each raw material at 80℃ and vacuum degree -0.08MPa for 6 hours, they are mixed at 100rpm for 8 minutes and added to a twin-screw extruder (length-to-diameter ratio L / D=41). The screw speed is 250rpm. The temperature of each zone of the extruder is set as follows: feeding zone 140℃, plasticizing zone 150℃, blending zone 170℃, homogenizing zone 175℃, and die 170℃. The material is melt-blended and granulated by the twin-screw extruder to obtain the waterproof layer feed.

[0183] Step 2: Control the weight ratio of the nonwoven fabric layer feed and the waterproof layer feed to 1:4. Add the nonwoven fabric layer feed and the waterproof layer feed to two extruders. The extruder used for the nonwoven fabric layer feed is set with an L / D ratio of 41, a screw speed of 100 rpm, a feeding zone temperature of 180°C, a compression zone temperature of 210°C, a metering zone temperature of 230°C, and a die temperature of 235°C. The extruder used for the waterproof layer feed is set with an L / D ratio of 41, a screw speed of 20 rpm, a feeding zone temperature of 160°C, a compression zone temperature of 180°C, a metering zone temperature of 195°C, and a die temperature of 200°C. After plasticizing and melting in the extruders, the materials are compounded through a co-extrusion die and co-extruded through the compound spinneret holes on the spinneret to obtain co-extruded composite filaments.

[0184] Step 3: The co-extruded composite filaments are cooled and shaped at 35°C in a side-blowing cooling zone (wind speed of 0.5m / s), and then blown onto a web forming curtain under the action of airflow to obtain a composite fiber web;

[0185] Step 4: The composite fiber web is fed into a hot rolling mill at 145℃ and a linear pressure of 70N / mm for hot pressing and bonding. After hot rolling, the nonwoven fabric is cooled, trimmed, and rolled up to obtain a high-strength waterproof composite nonwoven fabric.

[0186] Comparative Example 4

[0187] Comparative Example 4 is the same as Example 1, except that the modified ethylene propylene rubber obtained in Preparation Example 1 is replaced with the modified ethylene propylene rubber obtained in Comparative Preparation Example 4. Specifically:

[0188] A high-strength waterproof composite nonwoven fabric is a double-layer co-extruded composite nonwoven fabric, comprising a nonwoven fabric layer and a waterproof layer. The formulation and preparation method of each layer are as follows:

[0189] Step 1, Preparation of nonwoven fabric layer feed: Weigh 60 parts of polyethylene terephthalate (melting point 258℃, intrinsic viscosity 0.85dL / g) and 20 parts of hydrogenated rosin glycerol ester (softening point 100℃, hydroxyl value 6mgKOH / g). Dry each raw material at 85℃ and vacuum degree -0.08MPa for 4h, then mix them at 35rpm for 18min to obtain the nonwoven fabric layer feed;

[0190] Waterproof layer feed preparation: Weigh 30 parts of polybutene-1, 20 parts of modified ethylene propylene rubber prepared in Comparative Preparation Example 4, 2 parts of interface modifier prepared in Preparation Example 4, 10 parts of talc powder, 3 parts of titanium dioxide, 0.5 parts of 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol, and 0.5 parts of antioxidant (including antioxidant 1010 and antioxidant 168 in a mass ratio of 1:2). After drying each raw material at 80℃ and vacuum degree -0.08MPa for 6 hours, they are mixed at 100rpm for 8 minutes and added to a twin-screw extruder (length-to-diameter ratio L / D=41). The screw speed is 250rpm. The temperature of each zone of the extruder is set as follows: feeding zone 140℃, plasticizing zone 150℃, blending zone 170℃, homogenizing zone 175℃, and die 170℃. The material is melt-blended and granulated by the twin-screw extruder to obtain the waterproof layer feed.

[0191] Step 2: Control the weight ratio of the nonwoven fabric layer feed and the waterproof layer feed to 1:4. Add the nonwoven fabric layer feed and the waterproof layer feed to two extruders. The extruder used for the nonwoven fabric layer feed is set with an L / D ratio of 41, a screw speed of 100 rpm, a feeding zone temperature of 180°C, a compression zone temperature of 210°C, a metering zone temperature of 230°C, and a die temperature of 235°C. The extruder used for the waterproof layer feed is set with an L / D ratio of 41, a screw speed of 20 rpm, a feeding zone temperature of 160°C, a compression zone temperature of 180°C, a metering zone temperature of 195°C, and a die temperature of 200°C. After plasticizing and melting in the extruders, the materials are compounded through a co-extrusion die and co-extruded through the compound spinneret holes on the spinneret to obtain co-extruded composite filaments.

[0192] Step 3: The co-extruded composite filaments are cooled and shaped at 35°C in a side-blowing cooling zone (wind speed of 0.5m / s), and then blown onto a web forming curtain under the action of airflow to obtain a composite fiber web;

[0193] Step 4: The composite fiber web is fed into a hot rolling mill at 145℃ and a linear pressure of 70N / mm for hot pressing and bonding. After hot rolling, the nonwoven fabric is cooled, trimmed, and rolled up to obtain a high-strength waterproof composite nonwoven fabric.

[0194] Comparative Example 5

[0195] Comparative Example 5 is the same as Example 1, except that the interface modifier obtained in Preparation Example 4 is replaced with the interface modifier obtained in Comparative Preparation Example 5. Details are as follows:

[0196] A high-strength waterproof composite nonwoven fabric is a double-layer co-extruded composite nonwoven fabric, comprising a nonwoven fabric layer and a waterproof layer. The formulation and preparation method of each layer are as follows:

[0197] Step 1, Preparation of nonwoven fabric layer feed: Weigh 60 parts of polyethylene terephthalate (melting point 258℃, intrinsic viscosity 0.85dL / g) and 20 parts of hydrogenated rosin glycerol ester (softening point 100℃, hydroxyl value 6mgKOH / g). Dry each raw material at 85℃ and vacuum degree -0.08MPa for 4h, then mix them at 35rpm for 18min to obtain the nonwoven fabric layer feed;

[0198] Waterproof layer feed preparation: Weigh 30 parts of polybutene-1, 20 parts of modified ethylene propylene rubber prepared in Preparation Example 1, 2 parts of interface modifier prepared in Comparative Preparation Example 5, 10 parts of talc powder, 3 parts of titanium dioxide, 0.5 parts of 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol, and 0.5 parts of antioxidant (including antioxidant 1010 and antioxidant 168 in a mass ratio of 1:2). After drying each raw material at 80℃ and vacuum degree -0.08MPa for 6 hours, they are mixed at 100rpm for 8 minutes and added to a twin-screw extruder (length-to-diameter ratio L / D=41). The screw speed is 250rpm. The temperature of each zone of the extruder is set as follows: feeding zone 140℃, plasticizing zone 150℃, blending zone 170℃, homogenizing zone 175℃, and die 170℃. The material is melt-blended and granulated by the twin-screw extruder to obtain the waterproof layer feed.

[0199] Step 2: Control the weight ratio of the nonwoven fabric layer feed and the waterproof layer feed to 1:4. Add the nonwoven fabric layer feed and the waterproof layer feed to two extruders. The extruder used for the nonwoven fabric layer feed is set with an L / D ratio of 41, a screw speed of 100 rpm, a feeding zone temperature of 180°C, a compression zone temperature of 210°C, a metering zone temperature of 230°C, and a die temperature of 235°C. The extruder used for the waterproof layer feed is set with an L / D ratio of 41, a screw speed of 20 rpm, a feeding zone temperature of 160°C, a compression zone temperature of 180°C, a metering zone temperature of 195°C, and a die temperature of 200°C. After plasticizing and melting in the extruders, the materials are compounded through a co-extrusion die and co-extruded through the compound spinneret holes on the spinneret to obtain co-extruded composite filaments.

[0200] Step 3: The co-extruded composite filaments are cooled and shaped at 35°C in a side-blowing cooling zone (wind speed of 0.5m / s), and then blown onto a web forming curtain under the action of airflow to obtain a composite fiber web;

[0201] Step 4: The composite fiber web is fed into a hot rolling mill at 145℃ and a linear pressure of 70N / mm for hot pressing and bonding. After hot rolling, the nonwoven fabric is cooled, trimmed, and rolled up to obtain a high-strength waterproof composite nonwoven fabric.

[0202] Comparative Example 6

[0203] Comparative Example 6 is the same as Example 1, except that the interface modifier obtained in Preparation Example 4 is replaced with the interface modifier obtained in Comparative Preparation Example 6. Details are as follows:

[0204] A high-strength waterproof composite nonwoven fabric is a double-layer co-extruded composite nonwoven fabric, comprising a nonwoven fabric layer and a waterproof layer. The formulation and preparation method of each layer are as follows:

[0205] Step 1, Preparation of nonwoven fabric layer feed: Weigh 60 parts of polyethylene terephthalate (melting point 258℃, intrinsic viscosity 0.85dL / g) and 20 parts of hydrogenated rosin glycerol ester (softening point 100℃, hydroxyl value 6mgKOH / g). Dry each raw material at 85℃ and vacuum degree -0.08MPa for 4h, then mix them at 35rpm for 18min to obtain the nonwoven fabric layer feed;

[0206] Waterproof layer feed preparation: Weigh 30 parts of polybutene-1, 20 parts of modified ethylene propylene rubber prepared in Preparation Example 1, 2 parts of interface modifier prepared in Comparative Preparation Example 6, 10 parts of talc powder, 3 parts of titanium dioxide, 0.5 parts of 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol, and 0.5 parts of antioxidant (including antioxidant 1010 and antioxidant 168 in a mass ratio of 1:2). After drying each raw material at 80℃ and vacuum degree -0.08MPa for 6 hours, they are mixed at 100rpm for 8 minutes and added to a twin-screw extruder (length-to-diameter ratio L / D=41). The screw speed is 250rpm. The temperature of each zone of the extruder is set as follows: feeding zone 140℃, plasticizing zone 150℃, blending zone 170℃, homogenizing zone 175℃, and die 170℃. The material is melt-blended and granulated by the twin-screw extruder to obtain the waterproof layer feed.

[0207] Step 2: Control the weight ratio of the nonwoven fabric layer feed and the waterproof layer feed to 1:4. Add the nonwoven fabric layer feed and the waterproof layer feed to two extruders. The extruder used for the nonwoven fabric layer feed is set with an L / D ratio of 41, a screw speed of 100 rpm, a feeding zone temperature of 180°C, a compression zone temperature of 210°C, a metering zone temperature of 230°C, and a die temperature of 235°C. The extruder used for the waterproof layer feed is set with an L / D ratio of 41, a screw speed of 20 rpm, a feeding zone temperature of 160°C, a compression zone temperature of 180°C, a metering zone temperature of 195°C, and a die temperature of 200°C. After plasticizing and melting in the extruders, the materials are compounded through a co-extrusion die and co-extruded through the compound spinneret holes on the spinneret to obtain co-extruded composite filaments.

[0208] Step 3: The co-extruded composite filaments are cooled and shaped at 35°C in a side-blowing cooling zone (wind speed of 0.5m / s), and then blown onto a web forming curtain under the action of airflow to obtain a composite fiber web;

[0209] Step 4: The composite fiber web is fed into a hot rolling mill at 145℃ and a linear pressure of 70N / mm for hot pressing and bonding. After hot rolling, the nonwoven fabric is cooled, trimmed, and rolled up to obtain a high-strength waterproof composite nonwoven fabric.

[0210] Comparative Example 7

[0211] Comparative Example 7 is the same as Example 1, except that the interface modifier obtained in Preparation Example 4 is replaced with polypropylene. Details are as follows:

[0212] A high-strength waterproof composite nonwoven fabric is a double-layer co-extruded composite nonwoven fabric, comprising a nonwoven fabric layer and a waterproof layer. The formulation and preparation method of each layer are as follows:

[0213] Step 1, Preparation of nonwoven fabric layer feed: Weigh 60 parts of polyethylene terephthalate (melting point 258℃, intrinsic viscosity 0.85dL / g) and 20 parts of hydrogenated rosin glycerol ester (softening point 100℃, hydroxyl value 6mgKOH / g). Dry each raw material at 85℃ and vacuum degree -0.08MPa for 4h, then mix them at 35rpm for 18min to obtain the nonwoven fabric layer feed;

[0214] Preparation of waterproof layer feedstock: Weigh 30 parts of polybutene-1, 20 parts of modified ethylene propylene rubber prepared in Preparation Example 1, 2 parts of polypropylene, 10 parts of talc, 3 parts of titanium dioxide, 0.5 parts of 2-(4,6-diphenyl-1,3,5-triazine-2-yl)-5-[(hexyl)oxy]-phenol, and 0.5 parts of antioxidant (including antioxidant 1010 and antioxidant 168 in a mass ratio of 1:2). After drying each raw material at 80°C and vacuum degree -0.08MPa for 6 hours, mix them at 100 rpm for 8 minutes and add them to a twin-screw extruder (length-to-diameter ratio L / D=41). The screw speed is 250 rpm. The temperature of each zone of the extruder is set as follows: feeding zone 140°C, plasticizing zone 150°C, blending zone 170°C, homogenizing zone 175°C, and die 170°C. After melt blending and granulation in the twin-screw extruder, the waterproof layer feedstock is obtained.

[0215] Step 2: Control the weight ratio of the nonwoven fabric layer feed and the waterproof layer feed to 1:4. Add the nonwoven fabric layer feed and the waterproof layer feed to two extruders. The extruder used for the nonwoven fabric layer feed is set with an L / D ratio of 41, a screw speed of 100 rpm, a feeding zone temperature of 180°C, a compression zone temperature of 210°C, a metering zone temperature of 230°C, and a die temperature of 235°C. The extruder used for the waterproof layer feed is set with an L / D ratio of 41, a screw speed of 20 rpm, a feeding zone temperature of 160°C, a compression zone temperature of 180°C, a metering zone temperature of 195°C, and a die temperature of 200°C. After plasticizing and melting in the extruders, the materials are compounded through a co-extrusion die and co-extruded through the compound spinneret holes on the spinneret to obtain co-extruded composite filaments.

[0216] Step 3: The co-extruded composite filaments are cooled and shaped at 35°C in a side-blowing cooling zone (wind speed of 0.5m / s), and then blown onto a web forming curtain under the action of airflow to obtain a composite fiber web;

[0217] Step 4: The composite fiber web is fed into a hot rolling mill at 145℃ and a linear pressure of 70N / mm for hot pressing and bonding. After hot rolling, the nonwoven fabric is cooled, trimmed, and rolled up to obtain a high-strength waterproof composite nonwoven fabric.

[0218] The comprehensive performance of the high-strength waterproof composite nonwoven fabrics prepared in Examples 1-3 and Comparative Examples 1-7 of this invention was tested respectively.

[0219] 1. Gram weight test

[0220] The sample was tested using an electronic balance with an accuracy of 0.01g, in accordance with the GB / T 24218.1-2009 standard.

[0221] 2. Air permeability test

[0222] According to GB / T 5453-2025 standard, the samples were tested using a fabric air permeability analyzer under a pressure difference of 100Pa.

[0223] 3. Waterproof and breathable performance test

[0224] 3.1 Hydrostatic Pressure Resistance Test

[0225] Referring to the GB / T 4744-2013 standard, clamp the sample on the tester, increase the water pressure on one side at a rate of 60 mmH2O / min until 3 water droplets appear on the other side, and record the water pressure value at this time.

[0226] 3.2 Moisture permeability test

[0227] Referring to the GB / T 12704.1-2009 standard, the sample was sealed by covering it with a permeation cup containing desiccant and placed in a constant temperature and humidity environment. The rate of water vapor permeation through the sample was calculated by periodically weighing the weight gain of the permeation cup.

[0228] 4. Mechanical property testing

[0229] Referring to the GB / T24218.3-2010 standard, the tensile strength and elongation at break of the samples were tested using a constant rate of elongation tester (CRE), with the parameters set as follows: initial spacing of 200 mm and tensile speed of 100 mm / min.

[0230] 5. Peel strength

[0231] According to the FZ / T 60011-2016 standard, the peel strength of the samples was tested using a constant rate of elongation tester (CRE). The parameters were set as follows: initial spacing 100 mm, test speed 200 mm / min, and preload 0.1 N.

[0232] 6. UV aging resistance test

[0233] Referring to the ISO 4892-2:2013 standard, the samples were placed in a xenon lamp aging test chamber and subjected to simulated full-spectrum sunlight irradiation for 200 hours before their moisture permeability and tensile breaking strength were retested.

[0234] The test results are shown in Table 1-2:

[0235] Table 1. Data on basis weight, air permeability, moisture permeability, and mechanical properties of the high-strength waterproof composite nonwoven fabrics in Examples 1-3 and Comparative Examples 1-7.

[0236] Test Project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Weight (g / m²) 34.1 45.8 57.5 34.3 34.0 34.1 34.2 34.2 34.0 33.9 Air permeability (mm / s) 550 320 180 545 555 560 558 560 550 570 <![CDATA[Hydrostatic pressure (mmH2O)]]> 6540 7850 9210 4150 4320 3880 4010 6130 6250 5500 Moisture permeability (g / (m²·24h)) 1150 1080 990 1180 1165 1190 1185 1140 1155 1170 Breaking strength (N / 50mm) longitudinal / transverse 39.3 / 29.1 48.5 / 37.6 56.2 / 45.3 33.1 / 25.4 34.5 / 26.1 31.5 / 24.2 32.8 / 25.0 28.6 / 21.5 30.5 / 22.8 21.2 / 18.9 Elongation at break (%) longitudinal / transverse 36.2 / 58.4 38.5 / 62.1 40.1 / 65.8 25.8 / 45.7 27.3 / 48.2 24.1 / 43.5 25.5 / 45.1 29.1 / 49.5 30.8 / 51.3 24.5 / 41.1 Peel strength (N / 25mm) 5.32 6.85 8.16 5.25 5.30 4.85 5.02 1.85 2.54 0.68

[0237] Table 2. UV aging resistance test data of high-strength waterproof composite nonwoven fabrics in Examples 1-3 and Comparative Examples 1-7 (after 200h of irradiation).

[0238] Test Project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Moisture permeability (g / (m²·24h)) 1210 1105 1005 1550 1510 1620 1580 1380 1395 1450 Breaking strength (N / 50mm) longitudinal / transverse 35.1 / 25.9 45.2 / 35.1 54.0 / 43.5 22.5 / 17.1 23.8 / 18.0 19.8 / 15.2 21.0 / 16.3 19.5 / 14.8 21.1 / 15.6 12.3 / 10.2 Elongation at break (%) longitudinal / transverse 30.5 / 49.9 35.8 / 58.5 38.6 / 63.4 16.2 / 28.3 17.5 / 30.1 14.8 / 25.6 15.9 / 27.7 20.1 / 35.2 21.9 / 38.8 14.2 / 23.5

[0239] As shown in Table 1-2, the high-strength waterproof composite nonwoven fabrics prepared in Examples 1-3 of the present invention exhibit significant comprehensive advantages in mechanical properties, waterproof performance, interlayer bonding strength, and aging resistance compared with Comparative Examples 1-7.

[0240] As can be seen from Example 1 and Comparative Examples 1, 2, 3, and 4:

[0241] Comparative Example 1, with its modified ethylene propylene rubber, lacked vinyltrimethoxysilane, while Comparative Example 2, with its modified ethylene propylene rubber, lacked allyl polyether. Data showed that the sample from Example 1 significantly outperformed Comparative Examples 1 and 2 in terms of tensile strength, hydrostatic pressure, and strength retention after aging. This demonstrates that the simultaneous introduction of allyl polyether and vinyltrimethoxysilane is crucial for forming an effective cross-linked network and improving the performance of the composite nonwoven material.

[0242] Comparative Examples 3 and 4 used the exact same raw materials as Example 1, but changed the order of reactant addition. Data showed that the composite nonwoven fabrics obtained in Comparative Examples 3 and 4 exhibited inferior properties compared to Example 1, particularly in tensile strength and hydrostatic pressure, and even some properties were inferior to Comparative Examples 1 and 2. In Comparative Example 3, polymethylhydrosiloxane was added before vinyltrimethoxysilane. The highly reactive silane-hydrogen bonds reacted with other groups in the system, causing side reactions or premature crosslinking, which prevented the effective formation of the subsequent vinyltrimethoxysilane hydrolytic condensation network. In Comparative Example 4, adding vinyltrimethoxysilane before allyl polyether affected the grafting efficiency and distribution uniformity of the two active monomers on the ethylene propylene rubber backbone.

[0243] In summary, the specific order of "adding allyl polyether and vinyltrimethoxysilane first, followed by adding polymethylhydrosiloxane" adopted in this invention can achieve uniform and efficient crosslinking, thereby obtaining high-performance modified ethylene propylene rubber, which is non-obvious.

[0244] As demonstrated in Examples 1 and Comparative Examples 5 and 6, the use of an interface modifier co-grafted with epoxy groups and isocyanate groups is crucial for achieving high peel strength. Comparative Examples 5 and 6, using interface modifiers containing only a single functional group, exhibited significantly lower peel strengths than Example 1. This proves that the two active groups in the interface modifier of this invention can simultaneously react with different active sites (hydroxyl and carboxyl groups) on the surface of the nonwoven fabric layer. The two groups work synergistically to form a high-density chemically bonded interface, resulting in excellent interfacial adhesion.

[0245] As can be seen from Example 1 and Comparative Example 7, Comparative Example 7 directly used unmodified polypropylene to replace the interface modifier, resulting in a significant decrease in peel strength and easy delamination of the material, rendering it almost useless in practical applications. This demonstrates that the present invention, by introducing an interface modifier, successfully solves the fundamental technical problem of poor interfacial compatibility between materials of different polarities.

[0246] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims

1. A high-strength waterproof composite nonwoven fabric, characterized in that, The composite nonwoven fabric is a double-layer co-extruded composite nonwoven fabric, including a nonwoven fabric layer and a waterproof layer, wherein the weight ratio of the nonwoven fabric layer to the waterproof layer is 1-3:4-7. The nonwoven fabric layer comprises the following raw materials in parts by weight: 60-80 parts of high melting point polymer and 20-40 parts of low melting point polymer; The waterproof layer comprises the following raw materials in parts by weight: 30-50 parts of polybutene-1, 20-40 parts of modified ethylene propylene rubber, 2-8 parts of interface modifier, 10-20 parts of talc, 3-8 parts of titanium dioxide, 0.5-1.5 parts of ultraviolet absorber, and 0.5-1.5 parts of antioxidant. The modified ethylene propylene rubber is obtained by reacting ethylene propylene rubber with allyl polyether, vinyltrimethoxysilane and polymethylhydrosiloxane in sequence under the action of a platinum catalyst.

2. The high-strength waterproof composite nonwoven fabric according to claim 1, characterized in that, The The high-melting-point polymer in the nonwoven fabric layer is polyethylene terephthalate, with a melting point of 245-265℃ and an intrinsic viscosity of 0.70 dL / g-0.90 dL / g.

3. The high-strength waterproof composite nonwoven fabric according to claim 1, characterized in that, The The low-melting-point polymer in the nonwoven fabric layer is hydrogenated rosin glycerol ester, which has a softening point of 80-120℃ and a hydroxyl value of not less than 5mgKOH / g.

4. The high-strength waterproof composite nonwoven fabric according to claim 1, characterized in that, The The preparation method of modified ethylene propylene rubber in the waterproof layer includes the following steps: S1. Ethylene propylene rubber is put into a high-temperature internal mixer and melted and plasticized for 3-5 minutes to obtain ethylene propylene rubber melt; S2. Add allyl polyether and vinyltrimethoxysilane sequentially to the ethylene propylene rubber melt, and mix for 4-8 minutes to obtain an intermediate mixture; S3. Add polymethylhydrosiloxane to the intermediate mixture, mix for 1-2 minutes, then add platinum catalyst dropwise, and then heat to 170-180℃ and knead for 5-10 minutes to obtain modified ethylene propylene rubber material; S4. Compress the modified ethylene propylene rubber material into sheets, cool it, and cut it into pellets to obtain modified ethylene propylene rubber.

5. The high-strength waterproof composite nonwoven fabric according to claim 4, characterized in that, In S2, the mass ratio of ethylene propylene rubber melt, allyl polyether, and vinyltrimethoxysilane is 100:8-15:2-4; in S3, the mass ratio of polymethylhydrosiloxane and intermediate mixture is 1-5:110-119.

6. The high-strength waterproof composite nonwoven fabric according to claim 1, characterized in that, The The interface modifier in the waterproof layer is polypropylene co-grafted with glycidyl methacrylate and m-isopropenyl-α,α'-dimethylbenzyl isocyanate.

7. The high-strength waterproof composite nonwoven fabric according to claim 6, characterized in that, The The interface modifier in the waterproof layer is prepared by the following method: (1) Polypropylene and antioxidant 1076 are initially mixed in a mixer to obtain a solid mixture; glycidyl methacrylate, m-isopropenyl-α,α'-dimethylbenzyl isocyanate and initiator are premixed to obtain a liquid mixture; (2) The solid mixture is added to the twin-screw extruder. In the liquid injection zone, the liquid mixture is injected into the molten solid mixture by a high-pressure metering pump to carry out the melt grafting reaction and obtain the reacted melt. (3) The reacted melt is extruded, cooled, dried, and granulated, and then heated and dried under vacuum to obtain the interface modifier.

8. The high-strength waterproof composite nonwoven fabric according to claim 7, characterized in that, The (1) The mass ratio of polypropylene, antioxidant 1076, glycidyl methacrylate, m-isopropenyl-α,α'-dimethylbenzyl isocyanate and initiator is 100:0.1-0.5:2-8:1-5:0.1-0.

5.

9. The high-strength waterproof composite nonwoven fabric according to claim 1, characterized in that, The The antioxidant is a mixture of antioxidant 1010 and antioxidant 168.

10. A method for preparing a high-strength waterproof composite nonwoven fabric according to any one of claims 1-9, characterized in that, Includes the following steps: Step 1: By weight, dry the high-melting-point polymer and the low-melting-point polymer under vacuum conditions and mix them evenly to obtain the nonwoven fabric layer feed; dry the polybutene-1, modified ethylene propylene rubber, interface modifier, talc, titanium dioxide, ultraviolet absorber and antioxidant under vacuum conditions and mix them, then melt-blend and pelletize them through a twin-screw extruder to obtain the waterproof layer feed; Step 2: The non-woven fabric layer feed and the waterproof layer feed are added to two extruders for plasticization and melting, compounded through a co-extrusion die, and co-extruded through the composite spinneret holes on the spinneret to obtain co-extruded composite filaments; Step 3: The co-extruded composite filaments are cooled and shaped in the side-blowing cooling zone, and then blown onto the forming screen under the action of airflow to obtain a composite fiber web; Step 4: The composite fiber web is fed into a hot rolling mill for hot pressing and bonding. After hot rolling, the nonwoven fabric is cooled, trimmed, and rolled up to obtain a high-strength waterproof composite nonwoven fabric.