A method for preparing puncture-resistant and strong acid-alkali-resistant aramid composite fabric

Abstract

The invention discloses a method for preparing a puncture-resistant and strong acid-base resistant aramid composite fabric, comprising the following steps: spreading a composite coating solution on the aramid fabric, drying it, and obtaining the aramid composite fabric. The preparation method of the composite coating solution comprises the following steps: uniformly mixing inorganic particles and anhydrous ethanol to obtain solution A, uniformly mixing solution A and ammonia water under stirring conditions to obtain solution B, adding perfluorooctyl triethoxysilane to the solution B, stirring at 40 to 60° C. for 4 to 12 hours, cooling to room temperature, washing, and drying to obtain modified inorganic nanoparticles, adding modified inorganic nanoparticles to solution C under stirring conditions, stirring at 40 to 100° C. for 20 to 25 hours to obtain a composite coating solution, and using the composite coating solution of the invention to enhance the aramid fabric can simultaneously have super-hydrophobicity, puncture resistance, and strong acid-base resistance, and the super-hydrophobic composite coating has excellent mechanical stability and chemical robustness.

Description

Technical Field

[0001] The invention belongs to the technical field of textile materials, and in particular relates to a method for preparing puncture-resistant and strong acid- and alkali-resistant aramid composite fabric. Background Art

[0002] Medical, military, firefighting and other chemical personnel need special levels of protection when dealing with chemical and other threats in many special environments. Because the environment is potentially dangerous, they need to wear protective clothing to protect the entire body or a part of the body to avoid the threat of various harmful gases, liquids, chemicals or sharp knives, thereby effectively protecting the body from damage caused by sharp knives and reducing the risk of irreversible damage or disease to the skin. Therefore, the development of composite materials that are both superhydrophobic, resistant to strong acid and alkali corrosion, and puncture-resistant has very high practical value in the fields of firefighting, chemical industry and personal protection.

[0003] At present, the research on improving the puncture resistance of fabrics mainly focuses on the resin coating of fabrics and the treatment of impregnation with shear thickening liquid. However, since the coating surface contains hydrophilic groups that can maintain firm contact with the liquid, it accelerates surface corrosion, which greatly limits its scope of application. In order to make the fabric have acid and alkali corrosion resistance while having excellent puncture resistance, one of the effective strategies is to construct a superhydrophobic surface to control the surface wettability. In recent years, superhydrophobic surfaces have been widely studied and designed due to their unique anti-adhesion properties. However, due to their complex morphology, most of the preparation processes used are relatively complicated, and the mechanical durability and chemical stability are poor, which greatly limits their practical application. Summary of the invention

[0004] In view of the deficiencies in the prior art, the object of the present invention is to provide a method for preparing a composite coating solution. The preparation method first adopts a chemical grafting method to modify silica nanoparticles using a silane coupling agent to obtain modified inorganic nanoparticles; then DMF is used to dissolve thermoplastic polyurethane (TPU) to a certain concentration; and then the modified inorganic nanoparticles are dispersed in the uniformly dissolved TPU to obtain a composite coating solution with excellent mechanical properties, super hydrophobicity and acid and alkali resistance stability.

[0005] Another object of the present invention is to provide a composite coating solution obtained by the above preparation method.

[0006] Another object of the present invention is to provide a method for preparing puncture-resistant and strong acid and alkali-resistant aramid composite fabric, which adopts a scraping coating method to composite with the aramid fabric.

[0007] Another object of the present invention is to provide an aramid composite fabric obtained by the above method.

[0008] The purpose of the present invention is achieved through the following technical solutions.

[0009] A method for preparing a composite coating solution comprises the following steps:

[0010] 1) uniformly mixing inorganic particles and anhydrous ethanol to obtain solution A, and uniformly mixing solution A and aqueous ammonia under stirring to obtain solution B, wherein the inorganic particles include silicon dioxide nanoparticles, and the ratio of the mass fraction of the inorganic particles, the volume fraction of anhydrous ethanol and the volume fraction of aqueous ammonia is (1-10):(20-80):(4-20), the unit of the mass fraction is g, and the unit of the volume fraction is mL;

[0011] In the step 1), the inorganic particles further include silicon carbide nanoparticles, and the ratio of the silicon dioxide nanoparticles to the silicon carbide nanoparticles is (1-40): (1-10) by mass.

[0012] In the step 1), the concentration of the ammonia water is 1 to 10 wt %.

[0013] In the step 1), the particle size of the silicon dioxide nanoparticles is 12 to 600 nm, and the particle size of the silicon carbide nanoparticles is 40 to 600 nm.

[0014] In the step 1), the method for uniformly mixing the inorganic particles and anhydrous ethanol is: mixing the inorganic particles and anhydrous ethanol and ultrasonicating.

[0015] 2) adding perfluorooctyltriethoxysilane (PFOTS) to the solution B, stirring at 40-60° C. for 4-12 hours, cooling to room temperature, washing, and drying to obtain modified inorganic nanoparticles, wherein the ratio of the mass fraction of the inorganic particles to the volume fraction of the perfluorooctyltriethoxysilane is (1-10): (0.4-3);

[0016] In the step 2), the washing is performed alternately with anhydrous ethanol and distilled water.

[0017] In the step 2), the drying temperature is 50-130° C., and the drying time is at least 6 hours.

[0018] 3) adding modified inorganic nanoparticles to solution C under stirring, stirring at 40-100° C. for 20-25 hours to obtain a composite coating solution, wherein thermoplastic polyurethane (TPU) is dissolved in dimethylformamide (DMF) to form solution C, the ratio of the thermoplastic polyurethane to dimethylformamide is 2:12 by weight, and the ratio of the modified inorganic nanoparticles to solution C is (0.75-3):14 by weight;

[0019] In the step 3), the stirring speed is 100 to 500 r / min at 40 to 100°C.

[0020] In the step 3), thermoplastic polyurethane (TPU) and dimethylformamide (DMF) are mixed and stirred at 50-100° C. for 6-8 hours to obtain the solution C.

[0021] In the above technical solution, the rotation speed of stirring after mixing thermoplastic polyurethane (TPU) and dimethylformamide (DMF) is 100-600 r / min.

[0022] The composite coating solution obtained by the above preparation method.

[0023] A method for preparing puncture-resistant and strong acid-base resistant aramid composite fabric comprises the following steps: spreading the composite coating solution on the aramid fabric, drying it, and obtaining the aramid composite fabric.

[0024] In the above technical solution, the spreading method is scraping.

[0025] The aramid composite fabric is obtained by the above method.

[0026] The application of the composite coating solution in improving the puncture resistance / strong acid and alkali resistance / hydrophobicity of fabrics.

[0027] In the above technical solution, the material of the fabric is aramid, polyimide, ultra-high molecular weight polyethylene with an average weight greater than 3 million, poly(p-phenylene benzobisoxazole) or polyester.

[0028] The composite coating solution prepared by the present invention is used to reinforce the aramid fabric, which can simultaneously have super hydrophobicity, puncture resistance and strong acid and alkali resistance, and has excellent mechanical stability and chemical robustness. In addition, the preparation method is simple and safe. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 SEM of (a) aramid fabric and (b) aramid composite fabric prepared in Example 3;

[0030] Figure 2 Photos of droplets on the surface of (a) aramid fabric and (b) aramid composite fabric prepared in Example 3;

[0031] Figure 3 Photos of the self-cleaning process of (a) aramid fabric and (b) aramid composite fabric prepared in Example 3;

[0032] Figure 4 The contact angle and rolling angle variation curves of the aramid composite fabric sandpaper obtained in Example 3 during ten cycles of wear;

[0033] Figure 5 The aramid composite fabrics, TPU coated aramid fabrics and aramid fabrics (blank) prepared in Examples 1 to 4 are (a) the cone puncture force value-puncture displacement curve during the cone puncture process and (b) the average value of the maximum cone puncture force;

[0034] Figure 6 Aramid composite fabrics, TPU coated aramid fabrics and aramid fabrics (blank) prepared in Examples 1 to 4

[0035] (a) The curve of puncture force value-puncture displacement during the puncture process and (b) the average value of the maximum puncture force;

[0036] Figure 7 Aramid composite fabrics, TPU coated aramid fabrics and aramid fabrics (blank) obtained in Examples 5 to 8

[0037] (a) The curve of puncture force value-puncture displacement during cone puncture and (b) the average value of the maximum cone puncture force;

[0038] Figure 8 (a) weight loss rate of aramid fabric and aramid composite fabric prepared in Example 3 after immersion for 120 hours and (b) hydrophobic angle during immersion for 120 hours at different pH values;

[0039] Fig. 9 These are the strong acid and alkali resistance effect diagrams of the aramid composite fabric prepared in Example 3, wherein a from left to right are photographs of the aramid composite fabric dripped with sodium hydroxide aqueous solution for 0, 20, 40 and 60 minutes; b from left to right are photographs of the aramid composite fabric dripped with sulfuric acid for 0, 20, 40 and 60 minutes. DETAILED DESCRIPTION

[0040] The technical solution of the present invention is further described below in conjunction with specific embodiments.

[0041] 1H, 1H, 2H, 2H perfluorododecyl triethoxysilane (PFOTS, 97%) used in the examples were purchased from Aladdin, silica nanoparticles with a particle size of 20 nm (Degussa (China) Investment Co., Ltd.), thermoplastic polyurethane with a weight average molecular weight of 420,000 (Suzhou Xizhen Plastic Co., Ltd., China), N, N-dimethylformamide (DMF) (Tianjin Jiangtian Chemical Technology Co., Ltd.), aramid fabric (gram weight: 200 g / m2, thickness: 0.32 mm, the warp and weft density of the aramid fabric are both 60 yarns / 10 cm, and the yarn fineness of the fabric is 1500 denier) was provided by Yixing Carbon Technology Co., Ltd. Deionized water, anhydrous ethanol 99.7%, sodium hydroxide (96.0%), and sulfuric acid (98%) were obtained from Sinopharm Chemical Reagent Co., Ltd. (China). Silicon carbide nanoparticles with a particle size of 40 nm were purchased from Tianjin Jiangtian Chemical Technology Co., Ltd.

[0042] Example 1

[0043] A method for preparing a composite coating solution comprises the following steps:

[0044] 1) At room temperature of 20 to 25° C., silica nanoparticles with a particle size of 20 nm and anhydrous ethanol are mixed, and ultrasonicated for 0.5 h until the mixture is uniformly mixed to obtain solution A. Under stirring conditions, solution A is mixed with ammonia water with a concentration of 4.6 wt %, and stirred for 0.5 h until the mixture is uniformly mixed to obtain solution B, wherein the ratio of the mass fraction of silica nanoparticles, the volume fraction of anhydrous ethanol, and the volume fraction of ammonia water is 3:80:16, the unit of mass fraction is g, and the unit of volume fraction is mL;

[0045] 2) adding perfluorooctyltriethoxysilane (PFOTS) to solution B, stirring at 55° C. for 8 h, cooling to room temperature, washing alternately with anhydrous ethanol and distilled water (washing with anhydrous ethanol and distilled water 3 times each), and drying at 60° C. for 12 h to obtain modified inorganic nanoparticles, wherein the ratio of the mass fraction of silica nanoparticles to the volume fraction of perfluorooctyltriethoxysilane is 3:1.2;

[0046] 3) turning on magnetic stirring, adding modified inorganic nanoparticles to solution C under stirring, stirring at 60° C. and 400 r / min for 24 h to obtain a composite coating solution, wherein thermoplastic polyurethane (TPU) and dimethylformamide (DMF) are mixed, stirred at 80° C. and 500 r / min for 8 h to dissolve the thermoplastic polyurethane (TPU) in dimethylformamide (DMF) to form solution C, wherein the ratio of thermoplastic polyurethane to dimethylformamide is 2:12 by mass, and the ratio of modified inorganic nanoparticles to solution C is 0.75:14 by mass.

[0047] Example 2

[0048] A method for preparing a composite coating solution comprises the following steps:

[0049] 1) At room temperature of 20 to 25° C., silica nanoparticles with a particle size of 20 nm and anhydrous ethanol are mixed, and ultrasonicated for 0.5 h until the mixture is uniformly mixed to obtain solution A. Under stirring conditions, solution A is mixed with ammonia water with a concentration of 4.6 wt %, and stirred for 0.5 h until the mixture is uniformly mixed to obtain solution B, wherein the ratio of the mass fraction of silica nanoparticles, the volume fraction of anhydrous ethanol, and the volume fraction of ammonia water is 3:80:16, the unit of mass fraction is g, and the unit of volume fraction is mL;

[0050] 2) adding perfluorooctyltriethoxysilane (PFOTS) to solution B, stirring at 55° C. for 8 h, cooling to room temperature, washing alternately with anhydrous ethanol and distilled water (washing with anhydrous ethanol and distilled water 3 times each), and drying at 60° C. for 12 h to obtain modified inorganic nanoparticles, wherein the ratio of the mass fraction of silica nanoparticles to the volume fraction of perfluorooctyltriethoxysilane is 3:1.2;

[0051] 3) turning on magnetic stirring, adding modified inorganic nanoparticles to solution C under stirring conditions, stirring at 60° C. and 400 r / min for 24 h to obtain a composite coating solution, wherein thermoplastic polyurethane (TPU) and dimethylformamide (DMF) are mixed, stirred at 80° C. and 500 r / min for 8 h to dissolve the thermoplastic polyurethane (TPU) in dimethylformamide (DMF) to form solution C, wherein the ratio of thermoplastic polyurethane to dimethylformamide is 2:12 by mass, and the ratio of modified inorganic nanoparticles to solution C is 1:14 by mass.

[0052] Example 3

[0053] A method for preparing a composite coating solution comprises the following steps:

[0054] 1) At room temperature of 20 to 25° C., silica nanoparticles with a particle size of 20 nm and anhydrous ethanol are mixed, and ultrasonicated for 0.5 h until the mixture is uniformly mixed to obtain solution A. Under stirring conditions, solution A is mixed with ammonia water with a concentration of 4.6 wt %, and stirred for 0.5 h until the mixture is uniformly mixed to obtain solution B, wherein the ratio of the mass fraction of silica nanoparticles, the volume fraction of anhydrous ethanol, and the volume fraction of ammonia water is 3:80:16, the unit of mass fraction is g, and the unit of volume fraction is mL;

[0055] 2) adding perfluorooctyltriethoxysilane (PFOTS) to solution B, stirring at 55° C. for 8 h, cooling to room temperature, washing alternately with anhydrous ethanol and distilled water (washing with anhydrous ethanol and distilled water 3 times each), and drying at 60° C. for 12 h to obtain modified inorganic nanoparticles, wherein the ratio of the mass fraction of silica nanoparticles to the volume fraction of perfluorooctyltriethoxysilane is 3:1.2;

[0056] 3) turning on magnetic stirring, adding modified inorganic nanoparticles to solution C under stirring conditions, stirring at 60° C. and 400 r / min for 24 h to obtain a composite coating solution, wherein thermoplastic polyurethane (TPU) and dimethylformamide (DMF) are mixed, stirred at 80° C. and 500 r / min for 8 h to dissolve the thermoplastic polyurethane (TPU) in dimethylformamide (DMF) to form solution C, wherein the ratio of thermoplastic polyurethane to dimethylformamide is 2:12 by mass, and the ratio of modified inorganic nanoparticles to solution C is 1.25:14 by mass.

[0057] Example 4

[0058] A method for preparing a composite coating solution comprises the following steps:

[0059] 1) At room temperature of 20 to 25° C., silica nanoparticles with a particle size of 20 nm and anhydrous ethanol are mixed, and ultrasonicated for 0.5 h until the mixture is uniformly mixed to obtain solution A. Under stirring conditions, solution A is mixed with ammonia water with a concentration of 4.6 wt %, and stirred for 0.5 h until the mixture is uniformly mixed to obtain solution B, wherein the ratio of the mass fraction of silica nanoparticles, the volume fraction of anhydrous ethanol, and the volume fraction of ammonia water is 3:80:16, the unit of mass fraction is g, and the unit of volume fraction is mL;

[0060] 2) adding perfluorooctyltriethoxysilane (PFOTS) to solution B, stirring at 55° C. for 8 h, cooling to room temperature, washing alternately with anhydrous ethanol and distilled water (washing with anhydrous ethanol and distilled water 3 times each), and drying at 60° C. for 12 h to obtain modified inorganic nanoparticles, wherein the ratio of the mass fraction of silica nanoparticles to the volume fraction of perfluorooctyltriethoxysilane is 3:1.2;

[0061] 3) turning on magnetic stirring, adding modified inorganic nanoparticles to solution C under stirring conditions, stirring at 60° C. and 400 r / min for 24 h to obtain a composite coating solution, wherein thermoplastic polyurethane (TPU) and dimethylformamide (DMF) are mixed, stirred at 80° C. and 500 r / min for 8 h to dissolve the thermoplastic polyurethane (TPU) in dimethylformamide (DMF) to form solution C, wherein the ratio of thermoplastic polyurethane to dimethylformamide is 2:12 by mass, and the ratio of modified inorganic nanoparticles to solution C is 1.5:14 by mass.

[0062] Example 5

[0063] A method for preparing a composite coating solution comprises the following steps: 1) at room temperature of 20-25° C., mixing silicon dioxide nanoparticles with a particle size of 20 nm, silicon carbide nanoparticles with a particle size of 40 nm and anhydrous ethanol, and ultrasonicating for 0.5 h until the mixture is uniformly mixed to obtain solution A; under stirring conditions, mixing solution A with ammonia water with a concentration of 4.6 wt %, and stirring for 0.5 h until the mixture is uniformly mixed to obtain solution B, wherein the ratio of the mass fraction of silicon carbide nanoparticles, the mass fraction of silicon dioxide nanoparticles, the volume fraction of anhydrous ethanol and the volume fraction of ammonia water is 3:3:80:16, the unit of the mass fraction is g, and the unit of the volume fraction is mL;

[0064] 2) adding perfluorooctyltriethoxysilane (PFOTS) to solution B, stirring at 55° C. for 8 h, cooling to room temperature, washing alternately with anhydrous ethanol and distilled water (washing with anhydrous ethanol and distilled water 3 times each), and drying at 60° C. for 12 h to obtain modified inorganic nanoparticles, wherein the mass fraction of silicon carbide nanoparticles, the mass fraction of silicon dioxide nanoparticles and the volume fraction of perfluorooctyltriethoxysilane are 3:3:1.2;

[0065] 3) turning on magnetic stirring, adding modified inorganic nanoparticles to solution C under stirring condition, stirring at 60° C. and 400 r / min for 24 h to obtain a composite coating solution, wherein thermoplastic polyurethane (TPU) and dimethylformamide (DMF) are mixed, stirred at 80° C. and 500 r / min for 8 h to dissolve the thermoplastic polyurethane (TPU) in dimethylformamide (DMF) to form solution C, wherein the ratio of thermoplastic polyurethane to dimethylformamide is 2:12 by mass, and the ratio of modified inorganic nanoparticles to solution C is 2.25:14 by mass.

[0066] Example 6

[0067] A method for preparing a composite coating solution comprises the following steps:

[0068] 1) At room temperature of 20 to 25° C., silicon dioxide nanoparticles with a particle size of 20 nm, silicon carbide nanoparticles with a particle size of 40 nm and anhydrous ethanol are mixed, and ultrasonicated for 0.5 h until the mixture is uniformly mixed to obtain solution A. Under stirring conditions, solution A is mixed with ammonia water with a concentration of 4.6 wt %, and stirred for 0.5 h until the mixture is uniformly mixed to obtain solution B, wherein the ratio of the mass fraction of silicon carbide nanoparticles, the mass fraction of silicon dioxide nanoparticles, the volume fraction of anhydrous ethanol and the volume fraction of ammonia water is 3:3:80:16, the unit of mass fraction is g, and the unit of volume fraction is mL;

[0069] 2) adding perfluorooctyltriethoxysilane (PFOTS) to solution B, stirring at 55° C. for 8 h, cooling to room temperature, washing alternately with anhydrous ethanol and distilled water (washing with anhydrous ethanol and distilled water 3 times each), and drying at 60° C. for 12 h to obtain modified inorganic nanoparticles, wherein the mass fraction of silicon carbide nanoparticles, the mass fraction of silicon dioxide nanoparticles and the volume fraction of perfluorooctyltriethoxysilane are 3:3:1.2;

[0070] 3) turning on magnetic stirring, adding modified inorganic nanoparticles to solution C under stirring conditions, stirring at 60° C. and 400 r / min for 24 h to obtain a composite coating solution, wherein thermoplastic polyurethane (TPU) and dimethylformamide (DMF) are mixed, stirred at 80° C. and 500 r / min for 8 h to dissolve the thermoplastic polyurethane (TPU) in dimethylformamide (DMF) to form solution C, wherein the ratio of thermoplastic polyurethane to dimethylformamide is 2:12 by mass, and the ratio of modified inorganic nanoparticles to solution C is 2.5:14 by mass.

[0071] Example 7

[0072] A method for preparing a composite coating solution comprises the following steps:

[0073] 1) At room temperature of 20 to 25° C., silicon dioxide nanoparticles with a particle size of 20 nm, silicon carbide nanoparticles with a particle size of 40 nm and anhydrous ethanol are mixed, and ultrasonicated for 0.5 h until the mixture is uniformly mixed to obtain solution A. Under stirring conditions, solution A is mixed with ammonia water with a concentration of 4.6 wt %, and stirred for 0.5 h until the mixture is uniformly mixed to obtain solution B, wherein the ratio of the mass fraction of silicon carbide nanoparticles, the mass fraction of silicon dioxide nanoparticles, the volume fraction of anhydrous ethanol and the volume fraction of ammonia water is 3:3:80:16, the unit of mass fraction is g, and the unit of volume fraction is mL;

[0074] 2) adding perfluorooctyltriethoxysilane (PFOTS) to solution B, stirring at 55° C. for 8 h, cooling to room temperature, washing alternately with anhydrous ethanol and distilled water (washing with anhydrous ethanol and distilled water 3 times each), and drying at 60° C. for 12 h to obtain modified inorganic nanoparticles, wherein the mass fraction of silicon carbide nanoparticles, the mass fraction of silicon dioxide nanoparticles and the volume fraction of perfluorooctyltriethoxysilane are 3:3:1.2;

[0075] 3) turning on magnetic stirring, adding modified inorganic nanoparticles to solution C under stirring condition, stirring at 60° C. and 400 r / min for 24 h to obtain a composite coating solution, wherein thermoplastic polyurethane (TPU) and dimethylformamide (DMF) are mixed, stirred at 80° C. and 500 r / min for 8 h to dissolve the thermoplastic polyurethane (TPU) in dimethylformamide (DMF) to form solution C, wherein the ratio of thermoplastic polyurethane to dimethylformamide is 2:12 by mass, and the ratio of modified inorganic nanoparticles to solution C is 2.75:14 by mass.

[0076] Example 8

[0077] A method for preparing a composite coating solution comprises the following steps:

[0078] 1) At room temperature of 20 to 25° C., silicon dioxide nanoparticles with a particle size of 20 nm, silicon carbide nanoparticles with a particle size of 40 nm and anhydrous ethanol are mixed, and ultrasonicated for 0.5 h until the mixture is uniformly mixed to obtain solution A. Under stirring conditions, solution A is mixed with ammonia water with a concentration of 4.6 wt %, and stirred for 0.5 h until the mixture is uniformly mixed to obtain solution B, wherein the ratio of the mass fraction of silicon carbide nanoparticles, the mass fraction of silicon dioxide nanoparticles, the volume fraction of anhydrous ethanol and the volume fraction of ammonia water is 3:3:80:16, the unit of mass fraction is g, and the unit of volume fraction is mL;

[0079] 2) adding perfluorooctyltriethoxysilane (PFOTS) to solution B, stirring at 55° C. for 8 h, cooling to room temperature, washing alternately with anhydrous ethanol and distilled water (washing with anhydrous ethanol and distilled water 3 times each), and drying at 60° C. for 12 h to obtain modified inorganic nanoparticles, wherein the mass fraction of silicon carbide nanoparticles, the mass fraction of silicon dioxide nanoparticles and the volume fraction of perfluorooctyltriethoxysilane are 3:3:1.2;

[0080] 3) turning on magnetic stirring, adding modified inorganic nanoparticles to solution C under stirring, stirring at 60° C. and 400 r / min for 24 h to obtain a composite coating solution, wherein thermoplastic polyurethane (TPU) and dimethylformamide (DMF) are mixed, stirred at 80° C. and 500 r / min for 8 h to dissolve the thermoplastic polyurethane (TPU) in dimethylformamide (DMF) to form solution C, wherein the ratio of thermoplastic polyurethane to dimethylformamide is 2:12 by mass, and the ratio of modified inorganic nanoparticles to solution C is 3:14 by mass.

[0081] A method for preparing a puncture-resistant, strong acid and alkali-resistant aramid composite fabric, comprising the following steps: spreading 5 mL of one of the composite coating solutions obtained in Examples 1 to 8 on the aramid fabric by scraping, so that it is fully impregnated between the fibers of the aramid fabric, and drying at room temperature to obtain the aramid composite fabric, wherein the aramid fabric has a gram weight of 200 g / m 2 , the warp / weft density is 60 yarns / 10cm, the yarn fineness is 1500 denier aramid plain fabric, and its size is a square with a side length of 10cm.

[0082] Depend on Figure 1 (a) shows the smooth fiber surface of the aramid fabric. Figure 1 (b) shows that the surface of the prepared aramid composite fabric has obvious micro-nano rough structure.

[0083] Water droplets, milk droplets, coffee droplets, oil droplets, NaOH aqueous solution (40 wt%) droplets and H2SO4 (98 wt%) droplets were dropped on the surface of the aramid fabric and the aramid composite fabric prepared in Example 3, as shown in the photo. Figure 2 As shown by Figure 2 In (a), it can be observed that the dripping droplets easily penetrate the untreated aramid fabric. Figure 2 As shown in (b), when droplets fall on the aramid composite fabric prepared in Example 3, deionized water droplets, milk, coffee, oil, NaOH aqueous solution (40wt%) and H2SO4 (98wt%) maintain a stable spherical shape on the aramid composite fabric. This is because the nano-rough structure formed by the modified inorganic nanoparticles and TPU (thermoplastic polyurethane) captures the air layer on the fabric surface.

[0084] The aramid fabric and the aramid composite fabric prepared in Example 3 were placed in a glass container at a certain tilt angle, and carbon black was placed on the surface of the aramid fabric and the aramid composite fabric prepared in Example 3, and water was dripped on the carbon black to perform a self-cleaning simulation test. Figure 3It can be observed that when a water droplet is dropped onto the aramid fabric (Kevlar fabric) during the self-cleaning test using carbon black to simulate pollutants, the droplet quickly penetrates into the fabric and the carbon black remains on the surface of the fabric. Figure 3 It can be observed from b that the carbon black on the aramid composite fabric prepared in Example 3 is completely removed as the water droplets roll.

[0085] The aramid composite fabric prepared in Example 3 with a load of 100g was pulled horizontally and evenly on 400# sandpaper at a certain speed. The surface of the aramid composite fabric was fully in contact with the sandpaper. Each time the sample was pulled for 1m, it was recorded as one cycle, and the contact angle and rolling angle of the aramid composite fabric were measured. The contact angle and rolling angle change curves of the aramid composite fabric prepared in Example 3 during the ten cycles of sandpaper wear are shown as follows: Figure 4 As shown by Figure 4 It can be observed that the aramid composite fabric prepared in Example 3 still has super hydrophobicity after ten cycles of weight wear.

[0086] A method for preparing a TPU coated aramid fabric comprises: dissolving thermoplastic polyurethane (TPU) in N,N-dimethylformamide (DMF) to obtain a TPU solution with a TPU concentration of 15wt%, spreading 5mL of the obtained TPU solution on an aramid fabric by scraping to fully impregnate the TPU solution between fibers of the aramid fabric, and drying the solution at room temperature to obtain the TPU coated aramid fabric.

[0087] The different sample fabrics were fixed on the fixture of the universal strength tester, and the cone piercing head in the EN:388 standard was used to perform the cone piercing test on the universal strength tester at a speed of 100 mm / min. The aramid composite fabrics, TPU coated aramid fabrics and aramid fabrics prepared in Examples 1 to 4 were as follows: Figure 5 As shown in a, the aramid composite fabric, TPU coated aramid fabric and aramid fabric prepared in Examples 5 to 8 are as follows Figure 7 The cone puncture test was performed 5 times for each sample to obtain the average value of the maximum cone puncture force (cone puncture force). The average values ​​of the maximum cone puncture force (cone puncture force) of the aramid composite fabric, TPU coated aramid fabric and aramid fabric prepared in Examples 1 to 4 are shown in Figure 5 As shown in b, the average values ​​of the maximum cone puncture force (cone puncture force) of the aramid composite fabric, TPU coated aramid fabric and aramid fabric prepared in Examples 5 to 8 are as follows Figure 7 As shown in b. Figure 5 It can be observed that the aramid composite fabric prepared in Example 3 has the largest cone piercing force value, which is 1367.31% higher than that of the blank sample (aramid fabric). Figure 7It can be observed that the aramid composite fabric prepared in Example 7 has the largest cone puncture force value, which is increased by 1698.16% compared with the aramid fabric (blank).

[0088] Different sample fabrics were fixed on the fixture of a universal strength machine, and a knife stab test was performed at a speed of 100 mm / min using a P1 engineering blade. The knife stab force values ​​of the aramid composite fabrics, TPU coated aramid fabrics and aramid fabrics prepared in Examples 1 to 4 were as follows: Figure 6 The knife piercing test was performed 5 times on each sample to obtain the average value of the maximum knife piercing force (knife piercing force), as shown in FIG. Figure 6 As shown in b. Figure 6 It can be observed that the aramid composite fabric prepared in Example 3 has the largest knife penetration force value, which is increased by 457.51% compared with the aramid fabric (blank).

[0089] The aramid fabric and the aramid composite fabric prepared in Example 3 were placed in different pH solutions (the different pH solutions were pH = 1, 3, 5, 7, 9, 11, 13 and 14, sodium hydroxide aqueous solution when pH was less than 7, sulfuric acid when pH was greater than 7, and water when pH = 7) for 120 hours, taken out and dried at 80 ° C for 8 hours and weighed, and the weight loss rate was calculated, as shown in FIG. Figure 8 As shown in a;

[0090] The aramid fabric and the aramid composite fabric prepared in Example 3 were placed in solutions with pH = 1, 7 and 13 (the solutions were sulfuric acid, deionized water and sodium hydroxide aqueous solution), and dried at 80°C for 8 hours every 20 minutes, and their hydrophobic angles were measured. Figure 8 As shown in b.

[0091] Depend on Figure 8 It can be observed that, compared with aramid fabric ( Figure 8 Compared with the pure aramid fabric in a), the aramid composite fabric prepared in Example 3 has a lower weight loss rate after being immersed in acid and alkali solutions of different concentrations for a period of time. Figure 8 It can be observed from b that the aramid composite fabric prepared in Example 3 still has super hydrophobicity after being immersed in acid and alkali solutions of different concentrations for 120 hours.

[0092] The aramid composite fabric prepared in Example 3 was placed on a pH test paper, and a NaOH aqueous solution (40%) and a H2SO4 (98%) solution were dripped onto the aramid composite fabric respectively. The pH test paper was removed every 20 minutes to observe whether it was stained. Fig. 9 As shown in a, H2SO4 (98%) droplets are added as Fig. 9 As shown in b, Fig. 9It can be clearly observed that after the NaOH aqueous solution (40%) and H2SO4 (98%) droplets were dropped onto the surface of the aramid composite fabric prepared in Example 3 for 1 hour, they still showed a spherical shape and the pH test paper did not change color.

[0093] The present invention is described above by way of example. It should be noted that, without departing from the core of the present invention, any simple deformation, modification or other equivalent replacement that can be made by those skilled in the art without inventive effort falls within the protection scope of the present invention.

Claims

1. A method for preparing puncture-resistant, strong acid and alkali-resistant aramid composite fabric, characterized in that: The following steps are involved: The composite coating solution is spread on the aramid fabric and dried to obtain the aramid composite fabric, wherein the preparation method of the composite coating solution comprises the following steps: 1) uniformly mixing inorganic particles and anhydrous ethanol to obtain solution A, and uniformly mixing solution A and aqueous ammonia under stirring to obtain solution B, wherein the ratio of the mass fraction of the inorganic particles, the volume fraction of anhydrous ethanol and the volume fraction of aqueous ammonia is (1-10):(20-80):(4-20), the unit of the mass fraction is g, and the unit of the volume fraction is mL; 2) adding perfluorooctyltriethoxysilane to the solution B, stirring at 40-60° C. for 4-12 h, cooling to room temperature, washing, and drying to obtain modified inorganic nanoparticles, wherein the ratio of the mass fraction of the inorganic particles to the volume fraction of the perfluorooctyltriethoxysilane is (1-10):(0.4-3); 3) under stirring conditions, adding modified inorganic nanoparticles to solution C, stirring at 40-100° C. for 20-25 hours, to obtain a composite coating solution, wherein thermoplastic polyurethane is dissolved in dimethylformamide to form solution C, the ratio of the thermoplastic polyurethane to dimethylformamide is 2:12 by mass, the inorganic particles are a mixture of silicon dioxide nanoparticles and silicon carbide nanoparticles or silicon dioxide nanoparticles, and when the inorganic particles are silicon dioxide nanoparticles and silicon carbide nanoparticles When the inorganic particles are a mixture of silicon dioxide nanoparticles and silicon carbide nanoparticles, the ratio of the modified inorganic nanoparticles to solution C is (2.5-2.75):14 by weight; when the inorganic particles are a mixture of silicon dioxide nanoparticles and silicon carbide nanoparticles, the ratio of the silicon dioxide nanoparticles to the silicon carbide nanoparticles is (1-40):(1-10) by weight; when the inorganic particles are silicon dioxide nanoparticles, the ratio of the modified inorganic nanoparticles to solution C is (1-1.25):14 by weight.

2. The method according to claim 1, characterized in that In the step 1), the concentration of the ammonia water is 1-10 wt %.

3. The method according to claim 2, characterized in that In the step 1), the particle size of the silicon dioxide nanoparticles is 12-600 nm.

4. The method according to claim 3, characterized in that The particle size of the silicon carbide nanoparticles is 40-600 nm.

5. The method according to claim 4, characterized in that In the step 1), the method for uniformly mixing the inorganic particles and anhydrous ethanol is: mixing the inorganic particles and anhydrous ethanol and ultrasonicating.

6. The method according to claim 5, characterized in that In the step 2), the washing is performed alternately with anhydrous ethanol and distilled water.

7. The method according to claim 6, characterized in that In the step 2), the drying temperature is 50-130° C., and the drying time is at least 6 hours.

8. The method according to claim 7, characterized in that In the step 3), the stirring speed is 100-500 r / min at 40-100° C.

9. The method according to claim 8, characterized in that In the step 3), thermoplastic polyurethane and dimethylformamide are mixed and stirred at 50-100° C. for 6-8 hours to obtain the solution C.

10. The method according to claim 9, characterized in that Thermoplastic polyurethane and dimethylformamide are mixed and stirred at a speed of 100-600 r / min.

11. Aramid composite fabric obtained by the method according to any one of claims 1 to 10.

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