A method for preparing a broad-spectrum antibiotic and poison-resistant composite fabric

Abstract

The application discloses a preparation method of a composite fabric with broad-spectrum antibiochemical poisons. The preparation steps comprise the following steps: preparing MOF 808 powder material by using a hydrothermal method, then dispersing the MOF 808 in an acetic acid solution containing chitosan, then performing surface modification on the fabric by using atmospheric pressure low-temperature flat-plate dielectric barrier plasma, then soaking the fabric treated by the plasma in a suspension, then drying, reducing and preparing silver nanoparticles on the surface of the fabric in situ by magnetic stirring, and finally obtaining the broad-spectrum biochemistry protection composite fabric after washing and drying. The application has the beneficial effects that the limitations of single degradation function of MOF materials, long time consumption and complex process of the prior art are overcome, the problems of easy falling-off and low bonding force of the MOF materials are effectively solved, and a preparation method of a composite fabric with broad-spectrum antibiochemical poisons is provided.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of composite material preparation, and relates to a preparation method of a composite fabric with a broad-spectrum resistance to bio-chemical poisons. BACKGROUND

[0002] Chemical poisons mainly include nerve poisons and blistering agents represented by sulfur mustard (HD). The two poisons are usually released at the same time to cause irreversible damage to the nervous system and the external skin of personnel, respectively, and can cause casualties in as short as a few minutes. In response to the threat of bio-chemical poisons to the safety of personnel's lives, the current air-permeable protective clothing still mainly uses activated carbon materials to realize protection by physically adsorbing chemical poisons. However, the activated carbon materials have significant problems such as easy adsorption saturation, easy falling off, and limited protection duration, and it is urgent to develop bio-chemical poison protective clothing fabrics integrated with protection and sterilization functions. Loading nano materials with antibacterial and chemical poison degradation functions on the surface of the fabric can realize the "protection and sterilization integration" function of the protective fabric. New material metal-organic framework material (MOF) is a material with intramolecular pores formed by self-assembly of organic ligands and inorganic metal ions or clusters through coordination bonds, which can realize adsorption and degradation of toxic macromolecular substances in one body.

[0003] In recent years, MOF 808, as a six-node connected zirconium-based MOF material, has excellent chemical stability and good degradation of neurotoxicants. However, HD is a strong polar structure that is stable in the environment and is currently recognized as the most difficult to degrade chemical toxicants. Zhang et al., Fine Chemicals, 2021, 38(6): 1177-1182, loaded MOF 808 on a polyacrylonitrile (PAN) substrate to degrade HD simulant-2-chloroethyl ethyl sulfide (2-CEES), and found that even after 20 h, the degradation rate was only 83.7% (Zhang B., et al., Preparation of MOF-808@PAN Nanofiber and Degradation Performance of Mustard Gas, 2021, 38(6): 0). Since MOF 808 mainly exhibits adsorption for HD series toxicants, the defects of incomplete degradation and long time of MOF 808 are not sufficient to cope with the threat of simultaneous release of multiple toxicants in conflicts. Patent CN 114016206 A, 2021, used an electrospinning combined with calcination process to prepare a nanofiber membrane substrate loaded with V2O5, and verified the degradation effect of HD. This process requires 700°C for 270 min to prepare V2O5, so it cannot be effectively combined with MOF 808, which collapses at temperatures above 500°C. Patent US20200114189A1, 2020, deposited triethylenediamine (TEDA), a basic amino compound, on the surface and pore size of MOF 808, achieving a combined effect on neurotoxicants and blister agents. However, this process uses a flask container and TEDA, which requires 2-24 hours for deposition by heating sublimation, so the preparation time is long and the reaction conditions are harsh, limiting the further expansion of the modified composite material to the actual application of fabric surfaces.

[0004] In addition, the technology of loading MOF 808 material on the surface of the fabric is not mature. Commercial protective clothing is mainly made of high molecular materials, and PP fabric is the most widely used substrate for biochemical protective clothing, with a chemically inert surface and poor loading strength. If the particle material is directly adhered to the surface of the fabric using a spray adhesive process, it will severely block the pore structure of the MOF material, significantly affecting the efficiency of degrading chemical toxicants. In-situ growth is the most common technique for loading MOF on fabric surfaces, but the cost is high, the size of the fabric is limited by the volume of the container bottle, and the MOF material prepared by this method is easily detached from the surface of the fabric.

[0005] Therefore, the new generation of protective clothing not only needs to ensure the comfort of the wearer, but also needs to meet the demand of degrading a wide range of biochemical toxic substances. On this basis, it is of great significance to develop a process of stably connecting the particulate material and the base fabric and to extend it to industrial production and manufacturing. SUMMARY

[0006] In view of the above problems, the present application provides a preparation method of a composite fabric for resisting a wide range of biochemical toxic substances. Since the Ag nanoparticles have nucleophilic action with the Cl atoms contained in the HD, the hydrolysis reaction process of the HD can be effectively promoted. At the same time, Ag is a broad-spectrum antibacterial material with lower preparation condition restrictions. Therefore, the MOF 808 with high reactivity for neurotoxic substances and the Ag nanoparticles with nucleophilic action for HD are combined in the present application to realize higher selectivity and stability for biochemical warfare agent protection. The specific steps include the following steps:

[0007] Step 1: preparing MOF 808 powder material by using a hydrothermal method;

[0008] Step 2: dispersing the MOF 808 in a chitosan (CS) suspension to obtain a suspension 1;

[0009] Step 3: performing surface modification on the fabric by using atmospheric pressure low-temperature flat plate dielectric barrier (DBD) plasma;

[0010] Step 4: soaking the fabric treated by the plasma in the suspension 1 and performing drying treatment;

[0011] Step 5: adding a certain concentration of polyvinylpyrrolidone aqueous solution, N-N dimethylformamide and AgNO3 solution to the suspension 1 to obtain a suspension 2, and preparing silver nanoparticles in situ on the surface of the fabric by magnetic stirring;

[0012] Step 6: washing the residual suspension 2 and performing drying treatment to prepare a wide-spectrum biochemical protection composite fabric loaded with MOF 808 and nano-silver. Preferably, in the step 1, a mixed solution with a volume ratio of water to formic acid of 1:1 to 5:1 is configured in a pressure vessel, 1-10 mmol of zirconium chloride and 1-10 mmol of 1,3,5-benzene tricarboxylic acid are sequentially added, the mixed solution is uniformly mixed, the pressure vessel is placed in a 100℃ oven for 24 hours, the powder in the precipitate is collected by centrifugation, and the powder is dried at 60℃ for 24 hours to remove the residual organic solvent on the surface and activated at 120℃ for 8 hours to remove the residual reaction molecules in the pores of the powder to prepare the MOF 808 powder.

[0013] Further, the step 2 configures a 1%-3% acetic acid solution containing 0.1%-5% w / v chitosan, disperses MOF808 powder in the chitosan-containing acetic acid solution at an addition amount of 0.01-1 g / mL, mixes using magnetic stirring at a speed of 800-4000 rpm for 3-30 min, and configures suspension 1.

[0014] Further, the step 3 preferably uses PP fabric as a protective material substrate, uses a pulse source with a voltage of 8-13 kV, a frequency of 1-3 kHz, and a pulse width of 30-100 ns, and excites the atmospheric pressure low-temperature flat plate dielectric barrier plasma to surface treat the PP fabric for 1-30 min.

[0015] Further, the step 4 has a soaking time of 3-30 min, a drying temperature of 60-100°C, and a drying time of 20-60 min.

[0016] Further, the step 5 configures a 5-30% aqueous solution of polyvinylpyrrolidone, adds 20-40 wt% N-N dimethylformamide, and dropwise adds 10-20 wt% silver nitrate aqueous solution to prepare suspension 2, and magnetically stirs for 1-4 h.

[0017] Further, the step 6 uses distilled water to rinse the composite fabric 1-5 times, and dries at 60-90°C for 20-60 min to prepare the composite fabric.

[0018] The present application has the beneficial effect that the use of Ag nanoparticles and MOF 808 mixed materials overcomes the limitations of single degradation function of MOF materials, and effectively acts on neurotoxicants, blowing agents, and biological strains, and has the effect of broad-spectrum protection. The use of atmospheric pressure low-temperature plasma modification means and the use of chitosan as a connecting agent effectively solve the problem of long time and complex process in the prior art, and a composite fabric preparation method for broad-spectrum antibiochemical poisons is provided.

[0019] Compared with the prior art, the present application has the following advantages:

[0020] (1) The present application uses low-cost chitosan as a connecting agent, and realizes the simultaneous connection of MOF 808 and Ag nanoparticle materials through a fast self-assembly process. This is because the surface of chitosan is rich in a large number of hydroxyl groups which are directly connected to the hydroxyl groups of MOF 808 through hydrogen bonding, and the Ag nanoparticle material has excellent chelation properties with the amino groups on the surface of chitosan. Unlike in-situ growth method, the process of preparing MOF 808 and assembling MOF on the surface of the fabric is separated, which not only effectively shortens the preparation time of MOF fabric, but also controls the addition amount of MOF 808 in the chitosan solution, and realizes the optimization adjustment of degradation characteristics.

[0021] (2) The present application uses an atmospheric pressure low-temperature plasma modification method to treat fabric, which is environmentally friendly, energy efficient and high efficiency. The large amount of oxygen-containing functional groups generated by plasma collision on the surface of the substrate effectively enhance the bonding force between the chitosan shell and the base fabric. Since the atmospheric pressure DBD low-temperature plasma treatment is carried out at room temperature and atmospheric pressure, it is beneficial to maintain the original characteristics of the base fabric. As a non-contact method, it does not require the use of chemical reagents, reducing environmental pollution. And plasma treatment usually only needs a short time, the treatment process is fast and efficient, suitable for the treatment of large size fabric.

[0022] (3) The design method proposed in the present application has high detoxification function for both nerve toxicants and foaming agent representative simulators, which is a characteristic that conventional antidotes do not have. By combining the hydrolysis of nerve toxicants by MOF 808 and the nucleophilic function of Ag nanoparticles and HD, the material design can be used as a broad-spectrum protection against biochemical toxicants, while achieving excellent antibacterial effect on various strains of Escherichia coli, Pseudomonas aeruginosa and Bacillus sp. Therefore, it can be applied to the broad-spectrum protection of protective clothing, and has excellent military and commercial applications. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 The schematic diagram of the composite fabric of the present application. 1, Ag nanoparticles, 2, MOF 808 particles, 3, base fabric, 4, chitosan

[0024] Figure 2 The SEM image of MOF 808 and Ag nanoparticles loaded on the surface of the fabric.

[0025] Figure 3 The degradation efficiency curve of the composite fabric applied to toxicant simulators. a mustard gas simulator 2-chloroethyl ethyl sulfide (2-CEES), b simulant of sarin methyl parathion (DMNP).

[0026] Figure 4 The antibacterial efficiency curve of the composite fabric applied to. a Bacillus sp., b Escherichia coli, c Pseudomonas aeruginosa.

[0027] Figure 5 The TGA image of the composite fabric after ultrasonic treatment for 30 min. DETAILED DESCRIPTION

[0028] The present application will be further described in detail below through specific examples.

[0029] Example 1

[0030] A mixture of water and formic acid in a volume ratio of 3:2 was prepared in a pressure vessel, and zirconium chloride with a concentration of 5 mmol and 1,3,5-benzenetricarboxylic acid with a concentration of 6 mmol were sequentially added. After mixing, the pressure vessel was placed in an oven at 100 °C for 24 h. MOF 808 powder was collected from the precipitate by centrifugation, vacuum dried at 60 °C for 24 h, and activated at 120 °C for 8 h. A 1% acetic acid solution containing 1% w / v chitosan was prepared, and MOF 808 powder was dispersed in the chitosan-containing acetic acid solution at an addition amount of 0.1 g / mL. The solution was stirred using a magnetic stirrer to prepare a uniform solution. A polypropylene fabric was treated with atmospheric pressure low-temperature flat-plate dielectric barrier plasma for 5 min using a pulse source with a voltage of 10 kV, a frequency of 2 kHz, and a pulse width of 50 ns. The fabric was immersed in a mixture of MOF 808 and chitosan for 5 min and dried at 70 °C for 45 min. A 20% aqueous solution of polyvinylpyrrolidone was prepared, 10 wt% N-N dimethylformamide was added, and 5 wt% silver nitrate aqueous solution was added dropwise. After stirring for 2 h, the sample was washed with distilled water and dried at 70 °C for 45 min to prepare a composite fabric. A schematic diagram of the structure of the final product is shown in Figure 1 , and a SEM image of the composite fabric is shown in Figure 2 .

[0031] Example 2

[0032] A mixture of water and formic acid in a volume ratio of 1:1 was prepared in a pressure vessel, and zirconium chloride with a concentration of 3 mmol and 1,3,5-benzenetricarboxylic acid with a concentration of 8 mmol were sequentially added. After mixing, the pressure vessel was placed in an oven at 100 °C for 24 h. MOF 808 powder was collected from the precipitate by centrifugation, vacuum dried at 60 °C for 24 h, and activated at 120 °C for 8 h. A 1% acetic acid solution containing 1% w / v chitosan was prepared, and MOF 808 powder was dispersed in the chitosan-containing acetic acid solution at an addition amount of 0.05 g / mL. The solution was stirred using a magnetic stirrer to prepare a uniform solution. A polypropylene fabric was surface-treated using atmospheric pressure low-temperature flat-plate dielectric barrier plasma for 3 min using a pulse source with a voltage of 10 kV, a frequency of 3 kHz, and a pulse width of 50 ns. The fabric was immersed in a mixture of MOF 808 and chitosan for 10 min and dried at 60 °C for 30 min. A 20% aqueous solution of polyvinylpyrrolidone was prepared, 20 wt% N-N dimethylformamide was added, and 10 wt% silver nitrate aqueous solution was added dropwise. After stirring for 2 h, the sample was washed with distilled water and dried at 60 °C for 30 min to prepare a composite fabric. The degradation efficiency of the fabric for 2-chloroethyl ethyl sulfide (2-CEES) and methyl parathion (DMNP) is shown in Figure 3 .

[0033] Example 3

[0034] A mixture of water and formic acid with a volume ratio of 1:2 was prepared in a pressure vessel, and zirconium chloride with a concentration of 8 mmol, 1,3,5-benzenetricarboxylic acid with a concentration of 5 mmol were added in sequence. After mixing, the pressure vessel was placed in an oven at 100℃ for 24 hours. MOF 808 powder was collected from the precipitate by centrifugation, and dried at 60℃ for 24 hours under vacuum and activated at 120℃ for 8 hours. A 2% acetic acid solution containing 2% w / v chitosan was prepared, and MOF 808 powder was dispersed in the chitosan-containing acetic acid solution at an addition amount of 0.05 g / mL. A homogeneous solution was prepared using magnetic stirring. A polypropylene fabric was surface treated using atmospheric pressure low-temperature flat-plate dielectric barrier plasma with a pulse source of 8 kV voltage, 2 kHz frequency, and 50 ns pulse width for 3 min. The fabric was immersed in the MOF 808 and chitosan mixture for 5 min, and then dried at 70℃ for 30 min. A 20% aqueous solution of polyvinylpyrrolidone was prepared, and 20 wt% N-N dimethylformamide and 20 wt% silver nitrate aqueous solution were added. After magnetic stirring for 2 h, the sample was washed with distilled water, dried at 70℃ for 30 min, and a composite fabric was prepared. The antibacterial performance of the fabric against Bacillus, Escherichia coli, and Pseudomonas aeruginosa was tested as shown in Table 1. Figure 4

[0035] The above description is merely preferred embodiments of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application should be included in the protection scope of the present application.​

Claims

1. A method for preparing a composite fabric with broad-spectrum resistance to biochemical toxins, characterized in that, MOF 808 and Ag nanoparticles were prepared by self-assembly and in-situ reduction methods, respectively, and then fixed onto the surface of a low-temperature plasma-modified substrate via the intermediate chitosan, including the following steps: Step 1: Prepare a mixture of water and formic acid in a volume ratio of 1:1 to 1:5 in a pressure vessel using a hydrothermal method. Add zirconium chloride (1-10 mmol) and 1,3,5-pyromellitic acid (1-10 mmol) sequentially. After mixing thoroughly, place the pressure vessel in an oven at 100°C for 24 hours. Collect the MOF 808 powder from the precipitate by centrifugation. Obtain MOF 808 powder by vacuum drying at 60°C for 24 hours and vacuum activation at 120°C for 8 hours. Step 2: Prepare a 1%–3% acetic acid solution containing 0.1%–5% w / v chitosan. Disperse MOF 808 powder in the acetic acid solution containing chitosan at an addition rate of 0.01–1 g / mL. Mix with magnetic stirring at a speed of 800–4000 rpm for 3–30 min to obtain suspension 1. Step 3: Use a pulse source with a voltage of 8-13kV, a frequency of 1-3kHz, and a pulse width of 30-100ns to excite the atmospheric pressure low-temperature plate-type dielectric barrier electrode to generate low-temperature plasma and perform surface treatment on the PP fabric for 1-30 minutes. Step 4: Immerse the plasma-treated fabric in suspension 1 and dry it. Control the immersion time to be 3-30 min, the drying temperature to be 60-100℃, and the drying time to be 20-60 min. Step 5: Prepare a 5-30% polyvinylpyrrolidone aqueous solution, add 20-40 wt% N,N dimethylformamide, and dropwise add 10-20 wt% silver nitrate aqueous solution to form suspension 2. Place the fabric prepared in step 4 into suspension 2 and stir magnetically for 1-4 hours to grow Ag nanoparticles in situ on its surface to obtain composite fabric. Step 6: Rinse the composite fabric 1-5 times with distilled water and dry it at 60-90℃ for 20-60 min to obtain a broad-spectrum biochemical protective composite fabric loaded with MOF808 and nano silver.

2. The method according to claim 1, characterized in that, The substrate is polypropylene (PP) fabric, polyacrylonitrile (PAN) fabric, polyester fabric, aramid fabric, or activated carbon cloth.

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