Super-hydrophobic acid and alkali resistant fabric and processing method thereof

Abstract

The invention relates to a super-hydrophobic acid and alkali resistant fabric and a processing method thereof, the processing method comprises fabric pretreatment and surface modification treatment, the fabric pretreatment is to perform oxygen plasma etching on the fabric; the surface modification treatment is plasma surface activation-impregnation-plasma induced crosslinking treatment, and chemical bond fracture and reconstruction occur on the surfaces of the fabric and the modified material under the action of plasma, so that surface activation of the acid and alkali resistant nano material, chemical bond combination between the fabric and the nano material and crosslinking polymerization of silicon resin are realized; on one hand, the nanoparticles can be better dispersed in the silicon resin, and on the other hand, the interface bonding strength between the fabric and the nanoparticles can be improved. The process is reasonable in design and simple to operate, and the prepared fabric not only has excellent low surface energy and is endowed with good droplet adhesion resistance, but also has good acid and alkali resistance and corrosion resistance, can be applied to multiple protection fields, and has high practicability.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of textile fabrics, in particular to a super-hydrophobic acid and alkali resistant fabric and a processing method thereof. BACKGROUND

[0002] An acid and alkali resistant, oil resistant and water resistant fabric and garment is studied to prevent the human body from being injured by acid, alkali and special fuel chemicals when they run, drip or splash, which is an important guarantee for the life safety of rescue personnel.

[0003] Strong acid and strong alkali have a strong corrosive effect on fabric organization. In order to prevent the clothes of the staff from being decomposed by acid and alkali in emergency situations, the surface of the fabric needs to be modified to prevent direct contact between the fiber and the acid and alkali. The surface of the fabric is treated with water repellent to effectively prevent the adhesion of acid and alkali liquid on the surface of the fabric, thereby preventing the damage of acid and alkali chemicals to the human body. Therefore, the first step of acid and alkali resistance of the fabric is water repellent treatment, but for volatile hydrochloric acid and nitric acid, although the liquid acid drops cannot pass through the small gap in the organization, the acid molecules evaporated into gas are very small and can easily pass through the gap between the organization and the fiber. A single water repellent modification cannot play a good protective role. Therefore, domestic and foreign experts and scholars modify the surface of the fabric by using multi-component composite coating materials in order to improve the comprehensive acid resistance of the fabric.

[0004] At present, the materials for super-hydrophobic acid and alkali resistant finishing mainly include hydrophobic and smooth fluoroplastic, organic silicon, silicone rubber and inorganic nano materials, but there are problems such as difficult dispersion of nano materials, poor acid and alkali resistance, complex treatment process, and the inability to coexist of acid and alkali resistance and fabric comfort. The method of plasma powder modification, plasma surface activation and plasma induced crosslinking modification used in the present application can not only improve the dispersion of nano materials, but also improve the interfacial bonding strength between the composite coating of nano materials and low surface energy materials and the fiber fabric, improve the super-hydrophobic acid and alkali resistance of the fiber fabric, and at the same time, do not change the wearing performance of the fabric. SUMMARY

[0005] The present application aims to provide a super-hydrophobic acid and alkali resistant fabric and a processing method thereof, so as to solve the problems of toxicity, environmental pollution and increased cost caused by the use of fluorine-containing compounds and organic solvents in improving the super-hydrophobic acid and alkali resistant performance of fiber fabric in the background art. To this end, the present application forms a coating layer of low-surface-energy fluorine-free silicon-based resin and acid and alkali resistant nanomaterials after plasma surface grafting modification treatment by plasma-induced crosslinking technology to adhere to the surface of fiber fabric, thereby increasing the hydrophobicity of the fabric and imparting good acid and alkali resistance to the fabric. The above modification method solves the dispersion problem of acid and alkali resistant nanoparticles in water, so that the treatment process does not require the use of organic solvents, which can effectively reduce production cost and reduce environmental pollution. The present application provides a processing method of the above super-hydrophobic acid and alkali resistant fabric and its use as a functional textile fabric.

[0006] The present application is realized by the following technical solutions: The present application is inspired by the "earthworm skin" in nature, and is based on two principles of low surface energy and surface micro-convex structure for constructing acid and alkali resistant surface. Silicon resin oligomer is used as a low-surface-energy polymer for the preparation of super-hydrophobic functional fabric. By introducing acid and alkali resistant nanomaterials into the coating layer, the surface roughness of the fiber fabric is further improved, and the infiltration, adhesion and corrosion penetration of acid and alkali liquid on the fabric surface can be effectively prevented.

[0007] In a first aspect, the present application provides a super-hydrophobic acid and alkali resistant fabric and a processing method thereof, and the specific steps are as follows: (1) The acid and alkali resistant nanomaterials are subjected to low-pressure plasma surface modification treatment to obtain water-soluble nanomaterials; (2) The fiber fabric is subjected to atmospheric pressure plasma surface activation pretreatment to obtain pretreated fiber fabric; (3) The low-surface-energy polymer without fluorine and the water-soluble nanomaterials are added to a solvent and mixed thoroughly to obtain a composite dispersion liquid; (4) The pretreated fiber fabric is immersed in the composite dispersion liquid and subjected to ultrasonic oscillation, and then dried to obtain fiber fabric attached with acid and alkali resistant nanomaterials and low-surface-energy polymer; (5) The fiber fabric attached with acid and alkali resistant nanomaterials and low-surface-energy polymer is subjected to low-pressure plasma-induced crosslinking treatment to obtain a super-hydrophobic acid and alkali resistant fabric.

[0008] Further, in step (1), the acid and alkali resistant nanomaterials are selected from fluorine-containing polymers and / or oxide materials, preferably the fluorine-containing polymers are selected from one or more of PTFE, PVDF nanoparticles, and the oxide materials are selected from one or more of MgO, SiO2, TiO2; In step (1), the surface modification treatment is a low-pressure plasma surface modification treatment. After the acid- and alkali-resistant nanoparticles are subjected to plasma modification and activation treatment in a certain gas atmosphere, hydrophilic active groups are grafted on the surface of the nanomaterial, thereby increasing the dispersibility of the nanomaterial in water. The power of the low-pressure plasma surface modification treatment is 25-300 W, preferably 50-200 W, for example, 50 W, 75 W, 100 W, 125 W, 150 W, 175 W, 200 W; the working gas is one or more of oxygen, nitrogen, hydrogen, and ammonia, preferably oxygen and / or hydrogen, and the treatment time is 60-300 s, preferably 150-250 s, for example, 150 s, 180 s, 200 s, 250 s.

[0009] In step (2), the fiber fabric is one or more of aramid, cotton, polyester, and viscose fiber, preferably aramid, CVC 60 / 40, and polyester, and the fabric organization form is woven, knitted, braided, or non-woven, preferably woven or knitted.

[0010] Further, in step (3), the solvent is deionized water or anhydrous polar solvent, wherein the anhydrous polar solvent is at least one of anhydrous ethanol, acetone, and tetrahydrofuran, and is more preferably anhydrous ethanol; In step (3), the fluorine-free low-surface-energy polymer is a silicone resin, preferably polydimethylsiloxane (PDMS); and the concentration of the fluorine-free low-surface-energy substance in the composite dispersion liquid is 1-50 g / L, preferably 5-30 g / L, for example, 5 g / L, 10 g / L, 15 g / L, 20 g / L, 25 g / L, 30 g / L, 35 g / L, 40 g / L, 45 g / L, or 50 g / L. In step (3), the sufficient mixing is performed by high-speed stirring; the stirring speed in step (3) is 500-5000 r / min, preferably 1500-3000 r / min, for example, 500 r / min, 1000 r / min, 1500 r / min, 2000 r / min, 2500 r / min, or 3000 r / min; and the stirring time is 0.5-5 h, preferably 1-3 h, for example, 0.5 h, 1 h, 1.5 h, 2 h, 2.5 h, 3 h, 3.5 h, 4 h, 4.5 h, or 5 h.

[0011] In step (3), the concentration of the acid- and alkali-resistant nanomaterial in the composite dispersion liquid is 0.01-1.5 g / L, preferably 0.5-1 g / L, for example, 0.01 g / L, 0.1 g / L, 0.2 g / L, 0.5 g / L, 0.8 g / L, 1 g / L, 1.3 g / L, or 1.5 g / L.

[0012] Further, in step (4), the ultrasonic oscillation time is 10-30 min, preferably 15-20 min, for example, it can be 10 min, 15 min, 20 min, 25 min, 30 min; the immersion bath ratio is 1:10-1:100, preferably 1:30-1:60; for example, it can be 1:10, 1:20, 1:30, 1:40, 1:50, 1:60, 1:80, 1:100; the drying temperature is 60-150℃, preferably 80-120℃, for example, it can be 60℃, 82℃, 100℃, 120℃, 150℃; the drying time is 0.5-3h, preferably 1h, for example, it can be 0.5h, 1h, 1.5h, 2h, 2.5h, 3h.

[0013] The present application does not have special limitations for the equipment for providing the ultrasonic conditions, and any equipment known to those skilled in the art that can meet the above ultrasonic condition requirements can be used, and the mixing can be carried out at room temperature without additional heating or cooling.

[0014] Further, in step (5), the low-pressure plasma is used for the plasma-induced crosslinking treatment, which can better achieve the crosslinking polymerization of the silicone resin oligomer, coat the nanomaterials and firmly adhere them to the surface of the fiber fabric, and can simultaneously improve the superhydrophobicity and acid and alkali resistance of the fiber fabric. The low-pressure plasma discharge power source can be one of corona, radio frequency and pulse according to the frequency, the acting gas is argon / helium, the treatment power is 25-300W, preferably 50-100W, for example, it can be 50W, 75W, 100W, 150W, 200W, 250W, 300W; the pressure is 50-220mTorr, preferably 100-200mTorr, for example, it can be 70mTorr, 100mTorr, 125mTorr, 150mTorr, 175mTorr, 200mTorr, 220mTorr; the treatment time is 30-120s, preferably 40-100s, for example, it can be 30s, 60s, 90s, 120s.

[0015] In the second aspect, the present application provides a CVC60 / 40 fabric prepared by the above preparation method, wherein the CVC60 / 40 fabric has a water grade of 5, a penetration index of hydrochloric acid, nitric acid, sulfuric acid and sodium hydroxide solution ≤3%, and a liquid rejection rate ≥80%.

[0016] In the third aspect, the present application provides the use of the above CVC60 / 40 fabric in preparing acid and alkali resistant functional textiles.

[0017] In the fourth aspect, the present application provides an acid and alkali resistant functional textile prepared from the fiber fabric prepared by the above method or the above CVC60 / 40 fabric.

[0018] The technical scheme of the present application has the following advantages: (1) The super-hydrophobic acid and alkali resistant fabric and its processing method, the surface of the fiber fabric is coated with a silicon resin oligomer and an acid and alkali resistant nanomaterial, first, the surface is modified by low-pressure plasma grafting to graft polar functional groups on the surface of the nanomaterial, so that it can be better dispersed in the solvent; then the silicon resin oligomer and the surface-modified nanomaterial are mixed with the solvent by ultrasonic oscillation to prepare a uniformly dispersed composite dispersion liquid, in order to improve the adhesion uniformity and interfacial bonding strength of the silicon resin oligomer and the nanomaterial on the surface of the fiber fabric, the fiber fabric is first subjected to surface etching and activation by atmospheric pressure plasma; finally, a super-hydrophobic acid and alkali resistant fiber fabric is obtained by plasma-induced crosslinking treatment; the physical and mechanical properties of the treated fiber fabric are almost unchanged, which can meet the requirements of functional fabric on high physical and mechanical properties, and has good market application prospect.

[0019] (2) The super-hydrophobic acid and alkali resistant fabric and its processing method, the plasma treatment method used is dry throughout, which does not produce gas-liquid waste, has good environmental protection, the preparation process is simple and efficient, and is suitable for functional treatment of various fiber fabrics, which is conducive to meeting the functional treatment of acid and alkali resistant fabrics in different application scenarios, and has good industrialization prospect. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The particle size distribution graph of the composite water dispersion liquid of Example 1; Figure 2 The scanning electron microscope graph of the original CVC60 / 40 fiber fabric of Example 1; Figure 3 The scanning electron microscope graph of the plasma pretreated CVC60 / 40 fiber fabric of Example 1; Figure 4 The scanning electron microscope graph of the CVC60 / 40 fiber fabric after plasma-induced crosslinking treatment in Example 1; Figure 5 The scanning electron microscope graph of the CVC60 / 40 fiber fabric after plasma-induced crosslinking treatment in Example 2; Figure 6 In the table, (a) and (b) are the penetration index and liquid repellency efficiency of the CVC60 / 40 fiber fabric surface to different acids and bases before and after plasma-induced crosslinking treatment in Examples 1 and 2, respectively. DETAILED DESCRIPTION

[0021] The following will be described in detail with reference to the accompanying drawings. Figures 1-6 The present application will be further described in detail.

[0022] The present application discloses a super-hydrophobic acid and alkali resistant fabric and its processing method.

[0023] Example 1 Weigh 0.8g of PTFE nanoparticles (200nm in diameter) and place them in a plasma treatment chamber for surface grafting modification. The plasma treatment parameters are: 150W, oxygen, 200s, to prepare water-soluble PTFE nanoparticles. These nanoparticles are then added to 800ml of deionized water along with 24g of PDMS. The mixture is stirred at high speed at room temperature (3000r / min; 2h) to prepare a functional PTFE@PDMS composite aqueous dispersion (the particle size distribution of the composite aqueous dispersion is shown in the figure). Figure 1 (As shown).

[0024] A CVC60 / 40 knitted fabric of a certain size (not exceeding 20cm × 30cm) was examined using a scanning electron microscope (SEM) of the original CVC60 / 40 fiber fabric. Figure 2 The CVC60 / 40 knitted fabric was placed in an atmospheric pressure plasma treatment machine (power 300W; processing speed: 10mm / s; processing spacing: 2mm) to perform atmospheric pressure plasma surface treatment, resulting in pretreated CVC60 / 40 knitted fabric. (Scanning electron microscopy of plasma-pretreated CVC60 / 40 fiber fabric is shown in the image.) Figure 3 (As shown); then the pretreated CVC60 / 40 fabric was immediately immersed in the above PTFE@PDMS composite aqueous dispersion at a liquor ratio of 40:1, ultrasonically vibrated at room temperature for 10 min, and then dried at 80℃ for 1.5 h to obtain CVC60 / 40 knitted fabric with PTFE@PDMS attached; then the dried CVC60 / 40 knitted fabric was placed in a low-pressure plasma reaction chamber for modified treatment (acting gas: Ar, power: 150W, pressure: 225mTorr, treatment time: 80s) to obtain superhydrophobic and acid and alkali resistant PTFE@PDMS-g-PET fabric (SEM image of CVC60 / 40 fiber fabric after plasma-induced crosslinking treatment is shown in figure). Figure 4 (As shown).

[0025] Example 2 0.56 g of MgO nanoparticles (100 nm in diameter) were weighed and placed in a plasma treatment chamber for surface grafting modification. The plasma treatment parameters were: 200 W, hydrogen, 120 s, to prepare water-soluble MgO nanoparticles. These nanoparticles were then added to 800 ml of deionized water along with 16 g of PDMS and mixed at high speed at room temperature (2000 r / min; 2.5 h) to prepare a functional MgO@PDMS composite aqueous dispersion. CVC60 / 40 knitted fabric of a certain size (not exceeding 20 cm × 30 cm) was placed in an atmospheric pressure plasma treatment machine (200 W power; 5 mm / s processing speed; 2.5 mm processing spacing) to treat the CVC60 / 40 knitted fabric with atmospheric pressure plasma. Surface treatment was performed to obtain a pretreated CVC60 / 40 knitted fabric. The pretreated CVC60 / 40 fabric was then immediately immersed in the aforementioned MgO@PDMS composite aqueous dispersion at a bath ratio of 50:1, ultrasonically vibrated at room temperature for 15 minutes, and then dried at 120℃ for 1 hour to obtain a CVC60 / 40 knitted fabric coated with MgO@PDMS. The dried CVC60 / 40 knitted fabric was then subjected to a modified treatment in a low-pressure plasma reaction chamber (acting gas: He, power: 100W, pressure: 250mTorr, treatment time: 60s) to obtain a superhydrophobic and acid- and alkali-resistant MgO@PDMS-g-PET fabric (SEM image of the CVC60 / 40 fiber fabric after plasma-induced crosslinking treatment is shown in the image). Figure 5 (As shown).

[0026] Comparative Example 1 This comparative example is based on the original CVC60 / 40 fabric.

[0027] Comparative Example 2 This comparative example is a PDMS-coated CVC60 / 40 fabric. The preparation method is as follows: 5g of PDMS is added to 1000mL of deionized water and stirred at high speed at room temperature (3000r / min, 1.5h) to prepare a PDMS deionized water dispersion. A CVC60 / 40 knitted fabric of a certain size (not exceeding 20cm×30cm) is placed in an atmospheric pressure plasma treatment machine (150W power; processing speed: 5mm / s; processing spacing: 2.36mm) to perform atmospheric pressure plasma surface treatment on the CVC60 / 40 knitted fabric, obtaining a pre-coated... The pretreated CVC60 / 40 knitted fabric was then immediately immersed in the above-mentioned PDMS deionized water dispersion at a liquor ratio of 45:1. After ultrasonic vibration at room temperature for 10 min, it was dried at 120℃ for 1 h to obtain CVC60 / 40 knitted fabric with PDMS. Then, the dried CVC60 / 40 knitted fabric was placed in a low-pressure plasma reaction chamber for modified treatment (acting gas: Ar, power: 100W, pressure: 250mTorr, treatment time: 60s) to obtain PDMS-g-PET fabric.

[0028] Experimental Example The acid and alkali resistance, static water contact angle, water staining grade, tensile properties and bursting strength of the original CVC60 / 40 fabric (i.e., Comparative Example 1), the PDMS-coated CVC60 / 40 fabric prepared by Comparative Example 2, and the composite-coated CVC60 / 40 fabric prepared by Example 1 and Example 2 were tested respectively.

[0029] Acid and alkali resistance test: According to standard GB / T 24540—2009 "Protective Clothing - Chemical Protective Clothing", the penetration index and liquid repellency efficiency of the CVC60 / 40 fiber fabric surface before and after plasma-induced crosslinking treatment in Examples 1 and 2 are as follows: Figure 6 As shown.

[0030] Water repellency test: According to standard GB / T 4745-2012, the water repellency test is used to determine the surface moisture resistance of textile fabrics.

[0031] Tensile property test: according to standard GB / T 3923.2-2013 "Textiles - Tensile Properties of Fabrics".

[0032] Bursting strength test: according to standard GB / T 19976—2005 "Determination of bursting strength of textiles - steel ball method".

[0033] The test results are shown in Table 1.

[0034] Table 1. Static water contact angle, water repellency rating, tensile strength, tensile elongation at break, and bursting strength of different CVC60 / 40 fiber fabrics. As shown in Table 1, after impregnation-plasma treatment, the mechanical properties of the composite coated CVC60 / 40 fabrics prepared in Examples 1 and 2 are basically the same as those of the CVC60 / 40 fiber fabrics in Comparative Examples 1 and 2. They also have good superhydrophobic properties, a static water contact angle >150° and good anti-spray effect, with a water repellency rating of 5.

[0035] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A processing method for a superhydrophobic and acid / alkali resistant fabric, characterized in that: Includes the following steps: (1) Acid and alkali resistant nanomaterials were subjected to low-pressure plasma surface modification treatment to obtain water-soluble nanomaterials; (2) The fiber fabric is subjected to atmospheric pressure plasma surface activation pretreatment to obtain pretreated fiber fabric; (3) Add the fluorine-free low surface energy polymer and water-soluble nanomaterials to the solvent and mix thoroughly to obtain a composite dispersion; (4) The pretreated fiber fabric is immersed in the composite dispersion and subjected to ultrasonic vibration and drying to obtain a fiber fabric with acid and alkali resistant nanomaterials and low surface energy polymers attached. (5) The fiber fabric with acid and alkali resistant nanomaterials and low surface energy polymers attached is subjected to low-pressure plasma-induced crosslinking treatment to obtain superhydrophobic acid and alkali resistant fabric.

2. The processing method of the superhydrophobic acid and alkali resistant fabric according to claim 1, characterized in that: In step (1), the acid and alkali resistant nanomaterial is selected from fluoropolymers and / or oxide materials, the fluoropolymer is selected from one or more of PTFE and PVDF nanoparticles, and the oxide material is selected from one or more of MgO, SiO2 and TiO2; In step (1), the power of the low-pressure plasma surface modification treatment is 25~300 W, preferably 50~200 W, the working gas is one or more of oxygen, nitrogen, hydrogen and ammonia, and the treatment time is 60~300 s.

3. The processing method of the superhydrophobic acid and alkali resistant fabric according to claim 1, characterized in that, The power of the atmospheric pressure plasma surface activation pretreatment in step (2) is 50~500W, the treatment speed is 1~20mm / s, and the treatment spacing is 0.1~3mm; In step (2), the fiber fabric is one or more of aramid, cotton, polyester, and viscose fibers, and the fabric structure is woven, knitted, braided, or nonwoven.

4. The processing method of the superhydrophobic acid and alkali resistant fabric according to claim 1, characterized in that, In step (3), the solvent is deionized water or anhydrous polar solvent, wherein the anhydrous polar solvent is at least one of anhydrous ethanol, acetone, and tetrahydrofuran; In step (3), the fluorine-free low surface energy polymer is a silicone resin, and the silicone resin is polydimethylsiloxane (PDMS); the concentration of the fluorine-free low surface energy substance in the composite dispersion is 1~50 g / L, preferably 5~30 g / L; The thorough mixing in step (3) is carried out by high-speed stirring; the stirring speed in step (3) is 500~5000 r / min, and the stirring time is 0.5~5 h; In step (3), the concentration of acid and alkali resistant nanomaterials in the composite dispersion is 0.01~1.5 g / L.

5. The processing method of the superhydrophobic acid and alkali resistant fabric according to claim 1, characterized in that, As described in step (4), the ultrasonic oscillation time is 10~30 min; In step (4), the impregnation bath ratio is 1:10 to 1:100; In step (4), the drying temperature is 60~150℃ and the drying time is 0.5~3 h.

6. The processing method of the superhydrophobic acid and alkali resistant fabric according to claim 1, characterized in that, In step (5), the low-pressure plasma-induced crosslinking treatment discharge power supply can be one of corona, radio frequency, or pulse according to the frequency, the working gas is argon / helium, the processing power is 25~300 W, the pressure is 50~220 mTorr, and the processing time is 30~120 s.

7. A CVC60 / 40 fabric prepared by the method according to any one of claims 1-6, characterized in that, The CVC60 / 40 fabric has a water repellency rating of 5, a penetration index of ≤3% for hydrochloric acid, nitric acid, sulfuric acid and sodium hydroxide solutions, and a liquid repellency rate of ≥80%.

Images