Multi-layer protective material loaded with explosive beads, preparation method, and mask

Abstract

The invention relates to the technical field of multi-layer fabrics, and discloses a multi-layer protective material loaded with bursting beads, a preparation method, and a mask. The preparation method comprises: melting and reacting a polypropylene melt-blown resin and alkenyl nano zinc oxide under the action of an initiator, melt spinning, and obtaining an antibacterial polypropylene melt-blown cloth; pre-treating the antibacterial polypropylene melt-blown cloth, impregnating it with a finishing liquid and a silver nitrate aqueous solution, and obtaining a silver-loaded antibacterial polypropylene melt-blown cloth; compounding the silver-loaded antibacterial polypropylene melt-blown cloth with antibacterial bursting beads to obtain a drug-carrying layer; compounding a surface layer material, a polytetrafluoroethylene microporous membrane, a drug-carrying layer, and an inner layer material to obtain a multi-layer protective material loaded with bursting beads; using the multi-layer protective material loaded with bursting beads as the main material of a mask, cutting and compounding, and obtaining a multi-layer protective mask loaded with bursting beads. The multi-layer protective material has excellent antibacterial properties, and the mask prepared therefrom has good antibacterial properties and filtration properties.

Description

Technical Field

[0001] The invention relates to the technical field of multi-layer fabrics, and in particular to a multi-layer protective material loaded with explosive beads, a preparation method, and a mask. Background Art

[0002] Masks are tools worn around the mouth and nose to filter air and prevent pollutants from entering or leaving the air. Nonwoven air filter materials are fiber mesh materials made by arranging short fibers or filaments in a certain way and then reinforcing them. They have the advantages of simple processing technology, low cost, and high production efficiency. Polypropylene meltblown cloth, as an important component of the three-layer structure of nonwoven masks, has the advantages of high mechanical strength, corrosion resistance, acid and alkali resistance, light weight, low price, and non-toxicity and tastelessness. Compared with traditional woven or knitted air filter materials, polypropylene meltblown cloth has the advantages of fine fiber diameter, high porosity, high filtration efficiency and stable effect. It has been widely used as the main protective material of masks.

[0003] Prior art, such as Chinese patent application CN111674136A, discloses a protective mask and a method for preparing the same, wherein a fabric layer, a first porous membrane material layer, a two-component fabric layer, a second porous membrane material layer and a nonwoven fabric layer are laminated and compounded in sequence to obtain a mask main body material, and the mask has high filtering efficiency, low inhalation resistance, high efficiency in repelling liquid and mist, and washability through the compounding of the materials of each layer. However, the antibacterial and antimicrobial properties of the material are not improved when preparing the mask main body material, which limits the application of the material. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a multi-layer protective material loaded with explosive beads, a preparation method, and a mask. The multi-layer protective material has excellent antibacterial properties, and the mask prepared therefrom has good antibacterial and filtration properties.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A method for preparing a multi-layer protective material loaded with explosive beads comprises the following steps:

[0007] Step 1, preparing silver-loaded antibacterial polypropylene melt-blown cloth and antibacterial explosive beads;

[0008] The silver-loaded antibacterial polypropylene meltblown fabric is prepared by the following steps:

[0009] Step (1), mixing and dissolving vanillin and dichloromethane, adding pyridine, and dropping methacryloyl chloride solution at room temperature, reacting after the dropping is complete, and after the reaction is complete, removing the solvent dichloromethane by rotary evaporation, purifying, recrystallizing, and drying to obtain vanillin methacrylate;

[0010] Step (2), mixing nano zinc oxide, γ-aminopropylmethyldiethoxysilane and ethanol, reacting, filtering and washing after the reaction is completed to obtain amino nano zinc oxide; mixing amino nano zinc oxide, ethanol and methacrylate vanillin ester, reacting, filtering, washing and drying after the reaction is completed to obtain alkenyl nano zinc oxide;

[0011] Step (3), mixing polypropylene melt-blown resin, alkenyl nano zinc oxide, and dicumyl peroxide, and subjecting them to a melt reaction. After the reaction is completed, the mixture is melt-blown by a melt-blown spinning machine to obtain an antibacterial polypropylene melt-blown cloth;

[0012] Step (4), ultrasonically treating the antibacterial polypropylene melt-blown cloth in ethanol, and drying to obtain the pretreated antibacterial polypropylene melt-blown cloth; immersing the pretreated antibacterial polypropylene melt-blown cloth in a finishing liquid, reacting, taking out after the reaction, washing, and drying to obtain a modified antibacterial polypropylene melt-blown cloth; immersing the modified antibacterial polypropylene melt-blown cloth in a silver nitrate aqueous solution, immersing, taking out after the immersion, washing, and drying to obtain a silver-loaded antibacterial polypropylene melt-blown cloth;

[0013] The antibacterial explosive beads are prepared by the following steps:

[0014] Step (1), mixing and dissolving thymol and carbon tetrachloride, adding dibenzoyl peroxide and N-bromosuccinimide, reacting, after the reaction is completed, removing the solvent carbon tetrachloride by rotary evaporation to obtain brominated thymol; mixing brominated thymol, carbon tetrachloride and methacrylamide, reacting, after the reaction is completed, removing the solvent carbon tetrachloride by rotary evaporation to obtain alkenyl thymol;

[0015] The modified ethylene-vinyl acetate copolymer is obtained by mixing alkenyl thymol, ethylene-vinyl acetate copolymer and dicumyl peroxide, and performing a melt reaction. After the reaction is completed, the mixture is extruded and pelletized.

[0016] Step (2), using the essential oil aqueous solution as the core material of the antibacterial explosive beads, the modified ethylene-vinyl acetate copolymer as the wall material of the antibacterial explosive beads, and the ethanol aqueous solution as the coolant, and dripping the beads through a dripping pill machine to obtain the antibacterial explosive beads;

[0017] Step 2: silver-loaded antibacterial polypropylene meltblown cloth is used as the upper layer material and the lower layer material respectively, and antibacterial explosive beads are placed between the upper layer material and the lower layer material as the middle layer material to obtain a crude drug-loaded layer, and the edges of the crude drug-loaded layer are bonded and sealed to obtain a drug-loaded layer;

[0018] The surface layer material, polytetrafluoroethylene microporous membrane, drug-carrying layer and inner layer material are stacked and aligned in a stacking order to obtain a rough multi-layer protective material. The surface layer material and the inner layer material are both polypropylene spunbond non-woven fabrics. The edges of the rough multi-layer protective material are sealed to obtain a multi-layer protective material loaded with explosive beads.

[0019] Preferably, when preparing the modified antibacterial polypropylene melt-blown cloth in step 1, in step (1), the mass ratio of vanillin, dichloromethane, pyridine and methacryloyl chloride solution is 6-6.1:80-100:3.9-4:31.5-32, and the methacryloyl chloride solution is prepared by mixing and dissolving methacryloyl chloride and dichloromethane in a volume ratio of 1:4; the dropping conditions are: dropping at room temperature for 30-40 minutes; and the reaction conditions are: reacting at a temperature of 35-40°C for 5-8 hours.

[0020] Preferably, the purification operation comprises: mixing and dissolving the crude reaction product obtained after rotary evaporation with ethyl acetate in a mass ratio of 1:6-8, sequentially adding saturated sodium chloride aqueous solution, saturated sodium bicarbonate aqueous solution, and water to wash until neutral, wherein the mass ratio of the crude reaction product, saturated sodium chloride aqueous solution, saturated sodium bicarbonate aqueous solution, and water is 1:10-12:10-12:10-12, separating the liquids, taking the organic phase, adding 15-20% of the mass of the organic phase of anhydrous magnesium sulfate for dehydration for 20-30 minutes, filtering after dehydration, taking the filtrate, and removing the solvent ethyl acetate by rotary evaporation at a temperature of 50-60°C.

[0021] Preferably, the recrystallization operation includes: mixing and dissolving the reaction product obtained after purification with ethanol in a mass ratio of 1:2-3, adding water 8-10 times the mass of the reaction product, recrystallizing at a temperature of 0-5°C for 18-24h, filtering after recrystallization, taking the filter cake, and repeating the dissolving, recrystallizing, and filtering operations.

[0022] Preferably, when preparing the modified antibacterial polypropylene meltblown cloth in step 1, in step (2): the mass ratio of nano zinc oxide, γ-aminopropylmethyldiethoxysilane and ethanol is 1:0.9-1:120-150; when preparing amino nano zinc oxide, the reaction conditions are: stirring and reacting at room temperature for 2-3 hours; the mass ratio of amino nano zinc oxide, ethanol and vanillin methacrylate is 1:20-30:4-5; when preparing alkenyl nano zinc oxide, the reaction conditions are: reacting at a temperature of 45-55°C for 8-10 hours.

[0023] Preferably, when preparing the modified antibacterial polypropylene melt-blown cloth in step 1, in step (3): the mass ratio of polypropylene melt-blown resin, alkenyl nano zinc oxide, and dicumyl peroxide is 100:1-1.8:0.4-0.5; the melting reaction conditions are: in a twin-screw extruder, the screw speed is 280-300r / min, and the temperature is 230-240°C for melting reaction for 5-8min; the gram weight of the antibacterial polypropylene melt-blown cloth is 25-26g / m 2 .

[0024] Preferably, when preparing the modified antibacterial polypropylene meltblown cloth in step 1, in step (3): the operation of melt spinning is: pumping the antibacterial polypropylene melt into the spinneret at a temperature of 240-250°C, the melt pump speed is 200-220r / min, and the melt is stretched by hot air at a frequency of 36Hz and a temperature of 260°C, and then cooled and bonded into a web at a receiving distance of 20-25cm and a temperature of 5-10°C.

[0025] Preferably, when preparing the modified antibacterial polypropylene meltblown cloth in step 1, in step (4): the solid-liquid ratio of the antibacterial polypropylene meltblown cloth to ethanol is 1:20; the solid-liquid ratio of the pretreated antibacterial polypropylene meltblown cloth to the finishing liquid is 1:10-20; the reaction conditions are: stirring the reaction at room temperature for 4-5 hours; the solid-liquid ratio of the modified antibacterial polypropylene meltblown cloth to the silver nitrate aqueous solution is 1:50-60, and the silver nitrate aqueous solution is a 0.1 mol / L silver nitrate aqueous solution; and the immersion conditions are: immersion at room temperature for 8-10 hours.

[0026] Preferably, when the modified antibacterial polypropylene meltblown cloth is prepared in step 1, the finishing liquid in step (4) is prepared by the following steps: mixing dopamine hydrochloride, polyethyleneimine, tris(hydroxymethyl)aminomethane, and water, and adding a regulator to adjust the pH value to obtain a finishing liquid;

[0027] The mass ratio of dopamine hydrochloride, polyethyleneimine, tris(hydroxymethyl)aminomethane) and water is 1-1.2:1:1.2:800-1000; and the adjusted pH value is 8-8.5.

[0028] Preferably, the regulator comprises a 0.1 mol / L aqueous solution of hydrogen chloride.

[0029] Preferably, when preparing the antibacterial explosive beads in step 1, in step (1): the mass ratio of thymol, carbon tetrachloride, dibenzoyl peroxide, and N-bromosuccinimide is 3:160-200:0.1:3.7-3.75; when preparing brominated thymol, the reaction conditions are: reacting at a temperature of 50-60°C for 6-8h; the mass ratio of brominated thymol, carbon tetrachloride, and methacrylamide is 1.6:180-200:0.6-0.65; when preparing alkenyl thymol, the reaction conditions are: reacting at a temperature of 50-60°C for 5-6h.

[0030] Preferably, when preparing the antibacterial explosive beads in step 1, in step (1): the mass ratio of alkenyl thymol, ethylene-vinyl acetate copolymer, and diisopropylbenzene peroxide is 0.8-1:80:0.4-0.5; the melt reaction conditions are: in a twin-screw extruder, the speed is 60-80r / min, and the temperature is 120-140°C for melt reaction for 10-15min.

[0031] Preferably, when preparing the antibacterial bursting beads in step 1, in step (2): the essential oil aqueous solution is prepared by mixing water-soluble lavender essential oil, water-soluble menthol, water-soluble Millettia spatholobi extract, carboxymethyl chitosan, and water in a mass ratio of 1:1:1-1.5:0.5:50; the temperature of the core material is 50-55°C, the temperature of the wall material is 90-95°C, the concentration of the ethanol aqueous solution is 6 vol%, the temperature of the coolant is 25-30°C, and the drop height is 1 cm; the water content of the antibacterial bursting beads is 80%.

[0032] Preferably, in step 2: the weight of the drug-carrying layer is 52-53 g / m 2 When preparing multi-layer protective materials loaded with explosive beads, the weight of the surface material is 35g / m 2 The weight of the inner layer material is 25g / m 2 Sealing conditions: at a pressure of 220-250N / cm 2 , seal the edges of the rough multi-layer protective material at a temperature of 150-160°C.

[0033] Preferably, a multi-layer protective material loaded with explosive beads is prepared by the method for preparing a multi-layer protective material loaded with explosive beads as described above.

[0034] The present invention discloses a method for preparing a multi-layer protective mask loaded with bursting beads by using the multi-layer protective material loaded with bursting beads, comprising the following steps:

[0035] The multi-layer protective material loaded with bursting beads is used as the main material of the mask, and is cut according to size to obtain a mask body. The mask body is connected and compounded with ear rope sleeves to obtain a multi-layer protective mask loaded with bursting beads.

[0036] Preferably, a multi-layer protective mask loaded with bursting beads is prepared by the method for preparing a multi-layer protective mask loaded with bursting beads as described above.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] The invention prepares alkenyl nano zinc oxide with active groups, melt-reacts and grafts the alkenyl nano zinc oxide with polypropylene melt-blown resin to prepare antibacterial polypropylene melt-blown cloth, impregnates the cloth with finishing liquid and silver nitrate aqueous solution, and uses an impregnation method to modify the surface of the antibacterial polypropylene melt-blown cloth with polydopamine, polyethyleneimine and silver particles, thereby improving the antibacterial property of the melt-blown cloth. The obtained silver-loaded antibacterial polypropylene melt-blown cloth is compounded with antibacterial bursting beads to obtain a drug-loaded layer, and the multi-layer protective material loaded with bursting beads obtained by compounding with a surface layer material, a polytetrafluoroethylene microporous membrane and an inner layer material has excellent antibacterial property. The multi-layer protective material loaded with bursting beads is used as the main material of a mask, and the prepared multi-layer protective mask loaded with bursting beads has good antibacterial property and filtering property after cutting and compounding.

[0039] As a melt-blown nonwoven material, polypropylene melt-blown cloth has the advantages of fine fiber diameter, small pore size, large specific surface area, small filtration resistance, etc., and is widely used in air filtration materials; in the present invention, vanillin and methacryloyl chloride undergo nucleophilic substitution reaction to obtain methacrylic acid vanillin ester having a carbon-carbon double bond and an aldehyde group; an aminosilane coupling agent is used to modify the surface of nano zinc oxide, and the amino groups on the surface of amino nano zinc oxide undergo Schiff base reaction with the aldehyde groups of methacrylic acid vanillin ester to generate Schiff base bonds with antibacterial properties, thereby obtaining alkenyl nano zinc oxide having an active group carbon-carbon double bond and organic-inorganic synergistic antibacterial properties, which is mixed with a polypropylene melt-blown resin, and the alkenyl nano zinc oxide is grafted onto the main chain of the polypropylene resin under the condition of an initiator by a melt grafting method, thereby further improving the dispersibility and compatibility of the nano zinc oxide in the system, and the obtained antibacterial polypropylene melt-blown cloth has better antibacterial properties;

[0040] The present invention pre-treats the antibacterial polypropylene melt-blown cloth and then immerses it in a finishing liquid. In the finishing liquid, polyethyleneimine as a cross-linking agent can react with dopamine to form a cross-linked network, and a polydopamine / polyethyleneimine modified layer can be quickly formed on the surface of the melt-blown cloth. After the obtained modified antibacterial polypropylene melt-blown cloth is immersed in a silver nitrate solution, the silver ions can be reduced to form a silver element due to the reducing effect of polydopamine. At the same time, the active groups of polydopamine and polyethyleneimine can fix the silver particles, making them not easy to fall off, thereby further improving the antibacterial performance of the polypropylene melt-blown cloth.

[0041] The invention provides a method for preparing antibacterial explosive beads by melt-grafting the obtained alkenyl thymol with ethylene-vinyl acetate copolymer after bromination of thymol and the resultant alkenyl thymol undergoes a nucleophilic substitution reaction with methacrylamide to obtain a modified ethylene-vinyl acetate copolymer having a natural structure antibacterial agent, and compounding the modified ethylene-vinyl acetate copolymer with an essential oil aqueous solution containing water-soluble lavender essential oil, water-soluble menthol, water-soluble millettia spatholobi extract and carboxymethyl chitosan. The water-soluble lavender essential oil, water-soluble menthol, water-soluble millettia spatholobi extract and carboxymethyl chitosan are effective components of the essential oil aqueous solution and have antibacterial properties. Thymol is a natural antibacterial agent and can further improve the antibacterial ability of the antibacterial explosive beads.

[0042] The invention compounds the silver-loaded antibacterial polypropylene melt-blown cloth with antibacterial explosive beads to obtain a drug-loaded layer, and after compounding the drug-loaded layer with a surface layer material, a polytetrafluoroethylene microporous membrane, and an inner layer material, a multi-layer protective material loaded with explosive beads is obtained; wherein, the antibacterial explosive beads in the drug-loaded layer have an interface interaction with the surface of the silver-loaded antibacterial polypropylene melt-blown cloth, and can be evenly distributed on the surface of the melt-blown cloth; after the antibacterial explosive beads are broken, the effective components in the essential oil aqueous solution inside the antibacterial polypropylene melt-blown cloth are compounded, which can slow down the diffusion of the effective components and achieve a sustained-release antibacterial effect; in the structure composed of the drug-loaded layer, the surface layer material, the polytetrafluoroethylene microporous membrane, and the inner layer material, the drug-loaded layer and other layers of materials together constitute a spunbond-meltblown-spunbond structure, and this structure enables the multi-layer protective material to have both filtering performance and mechanical strength, and the multi-layer protective mask loaded with explosive beads is prepared by using the drug-loaded layer as the main material of a mask and cutting and compounding, and has good antibacterial performance and filtering performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a process flow chart of preparing a multi-layer protective mask loaded with bursting beads in the present invention;

[0044] Figure 2 It is a schematic diagram of the structure of the multi-layer protective material loaded with explosive beads prepared in the present invention;

[0045] Figure 3 It is a schematic structural diagram of a multi-layer protective mask loaded with bursting beads prepared in the present invention;

[0046] Figure 4 It is a bar graph of the antibacterial rates of Examples 1-3 and Comparative Examples 1-2 in the antibacterial performance test of the present invention;

[0047] In the figure:

[0048] 1. Surface layer material; 2. Polytetrafluoroethylene microporous membrane; 3. Drug-carrying layer; 301. Silver-carrying antibacterial polypropylene meltblown cloth; 302. Middle layer material; 4. Inner layer material. DETAILED DESCRIPTION

[0049] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0050] Example 1

[0051] This embodiment discloses a method for preparing a multi-layer protective material loaded with explosive beads, comprising the following steps:

[0052] Step 1, preparing silver-loaded antibacterial polypropylene melt-blown cloth and antibacterial explosive beads;

[0053] The silver-loaded antibacterial polypropylene meltblown fabric is prepared by the following steps:

[0054] Step (1), vanillin and dichloromethane are mixed and dissolved, pyridine is added, methacryloyl chloride solution is added dropwise at room temperature for 30 minutes, and after the addition is completed, the reaction is carried out at 35°C for 8 hours. After the reaction is completed, the solvent dichloromethane is removed by rotary evaporation at 30°C to obtain a crude reaction product, the crude reaction product is mixed and dissolved with ethyl acetate in a mass ratio of 1:6, and saturated sodium chloride aqueous solution, saturated sodium bicarbonate aqueous solution, and water are added in sequence to wash until neutral. The crude reaction product, saturated sodium chloride aqueous solution, saturated sodium bicarbonate aqueous solution, and water are washed with water until neutral. The mass ratio is 1:10:10:10, and the liquids are separated. The organic phase is taken, and anhydrous magnesium sulfate with a mass ratio of 15% of the organic phase is added for dehydration for 20 minutes. After dehydration, it is filtered, and the filtrate is taken. The solvent ethyl acetate is removed by rotary evaporation at a temperature of 50°C to obtain a reaction product. The reaction product is mixed and dissolved with ethanol at a mass ratio of 1:2, and water 8 times the mass of the reaction product is added. It is recrystallized at a temperature of 0°C for 18 hours. After recrystallization, it is filtered by suction, and the filter cake is taken. The operation of dissolving, recrystallizing, and filtering by suction is repeated once, and it is dried at a temperature of 40°C for 12 hours to obtain methacrylic acid vanillin ester;

[0055] The mass ratio of vanillin, dichloromethane, pyridine and methacryloyl chloride solution is 6:80:3.9:31.5, and the methacryloyl chloride solution is prepared by mixing and dissolving methacryloyl chloride and dichloromethane in a volume ratio of 1:4.

[0056] Step (2), mixing nano zinc oxide, γ-aminopropylmethyldiethoxysilane and ethanol in a mass ratio of 1:0.9:120, stirring and reacting at room temperature for 2 hours, filtering after the reaction, taking the filter cake, adding ethanol 5 times the mass of the filter cake to wash, and obtaining amino nano zinc oxide; mixing amino nano zinc oxide, ethanol and methacrylate vanillin ester in a mass ratio of 1:20:4, reacting at 45°C for 10 hours, filtering after the reaction, taking the filter cake, adding ethanol 5 times the mass of the filter cake to wash, and drying at 40°C for 24 hours to obtain alkenyl nano zinc oxide;

[0057] Step (3), polypropylene melt-blown resin, alkenyl nano zinc oxide, and dicumyl peroxide are mixed in a mass ratio of 100:1:0.4, and melt-reacted in a twin-screw extruder at a screw speed of 280 r / min and a temperature of 230° C. for 8 minutes. After the reaction is completed, melt-spinning is performed by a melt-blown spinning machine to obtain a 25 g / m 2 Antibacterial polypropylene meltblown fabric;

[0058] The operation of melt spinning is as follows: the antibacterial polypropylene melt is pumped into the spinneret at a temperature of 240°C, the melt pump speed is 200r / min, and the melt is stretched by hot air at a frequency of 36Hz and a temperature of 260°C, and then cooled and bonded into a web at a receiving distance of 20cm and a temperature of 5°C;

[0059] Step (4), ultrasonically treating the antibacterial polypropylene melt-blown cloth in ethanol for 20 minutes, the solid-liquid ratio of the antibacterial polypropylene melt-blown cloth to ethanol is 1:20, and drying at 50°C for 10 hours to obtain the pretreated antibacterial polypropylene melt-blown cloth; immersing the pretreated antibacterial polypropylene melt-blown cloth in a finishing liquid with a solid-liquid ratio of 1:10, stirring and reacting at room temperature for 4 hours, taking out after the reaction, adding water to wash until neutral, and drying at 50°C for 10 hours to obtain a modified antibacterial polypropylene melt-blown cloth; immersing the modified antibacterial polypropylene melt-blown cloth in a 0.1 mol / L silver nitrate aqueous solution, the solid-liquid ratio of the modified antibacterial polypropylene melt-blown cloth to the 0.1 mol / L silver nitrate aqueous solution is 1:50; immersing at room temperature for 8 hours, taking out after the immersion, adding water to wash until neutral, and drying at 50°C for 10 hours to obtain a silver-loaded antibacterial polypropylene melt-blown cloth;

[0060] The finishing liquid is prepared by the following steps: dopamine hydrochloride, polyethyleneimine, tris(hydroxymethyl)aminomethane) and water are mixed in a mass ratio of 1:1:1.2:800, and a 0.1 mol / L aqueous solution of hydrogen chloride is added to adjust the pH value to 8 to obtain a finishing liquid;

[0061] The antibacterial explosive beads are prepared by the following steps:

[0062] Step (1), mixing and dissolving thymol and carbon tetrachloride, adding dibenzoyl peroxide and N-bromosuccinimide, wherein the mass ratio of thymol, carbon tetrachloride, dibenzoyl peroxide and N-bromosuccinimide is 3:160:0.1:3.7, reacting at 50°C for 8h, and after the reaction is completed, removing the solvent carbon tetrachloride by rotary evaporation at 50°C to obtain brominated thymol; mixing brominated thymol, carbon tetrachloride and methacrylamide at a mass ratio of 1.6:180:0.6, reacting at 50°C for 6h, and after the reaction is completed, removing the solvent carbon tetrachloride by rotary evaporation at 50°C to obtain alkenyl thymol;

[0063] Alkenyl thymol, ethylene-vinyl acetate copolymer and dicumyl peroxide were mixed in a mass ratio of 0.8:80:0.4, and melt-reacted in a twin-screw extruder at a speed of 60 r / min and a temperature of 120° C. for 15 minutes. After the reaction was completed, the mixture was extruded and pelletized to obtain a modified ethylene-vinyl acetate copolymer;

[0064] Step (2), using the essential oil aqueous solution as the core material of the antibacterial explosive beads, the modified ethylene-vinyl acetate copolymer as the wall material of the antibacterial explosive beads, and 6 vol% ethanol aqueous solution as the coolant, and dripping the beads through a dripping pill machine to obtain the antibacterial explosive beads;

[0065] The essential oil aqueous solution is prepared by mixing water-soluble lavender essential oil, water-soluble menthol, water-soluble Millettia spatholobi extract, carboxymethyl chitosan and water in a mass ratio of 1:1:1:0.5:50; the temperature of the core material is 50°C, the temperature of the wall material is 90°C, the temperature of the coolant is 25°C, and the drop height is 1 cm; the water content of the antibacterial bursting beads is 80%;

[0066] Step 2: Use the silver-loaded antibacterial polypropylene meltblown cloth as the upper layer material and the lower layer material respectively, place the antibacterial explosive beads between the upper layer material and the lower layer material as the middle layer material, and obtain the crude drug-loaded layer. The edges of the crude drug-loaded layer are bonded and sealed at 100°C by a thermal bonding machine to obtain a 52g / m 2 The drug loading layer;

[0067] The surface layer material, the polytetrafluoroethylene microporous membrane, the drug-carrying layer, and the inner layer material are stacked and aligned in a stacking order to obtain a rough product of a multilayer protective material. The surface layer material and the inner layer material are both polypropylene spunbonded non-woven fabrics. The gram weight of the surface layer material is 35 g / m 2 The weight of the inner layer material is 25g / m 2 ; Under pressure 220N / cm 2 , seal the edges of the rough multi-layer protective material at a temperature of 150°C to obtain a multi-layer protective material loaded with explosive beads.

[0068] Example 2

[0069] This embodiment discloses a method for preparing a multi-layer protective material loaded with explosive beads, comprising the following steps:

[0070] Step 1, preparing silver-loaded antibacterial polypropylene melt-blown cloth and antibacterial explosive beads;

[0071] The silver-loaded antibacterial polypropylene meltblown fabric is prepared by the following steps:

[0072] Step (1), vanillin and dichloromethane are mixed and dissolved, pyridine is added, methacryloyl chloride solution is added dropwise at room temperature for 35 minutes, and after the addition is completed, the reaction is carried out at 38°C for 7 hours. After the reaction is completed, the solvent dichloromethane is removed by rotary evaporation at 33°C to obtain a crude reaction product, the crude reaction product is mixed and dissolved with ethyl acetate in a mass ratio of 1:7, saturated sodium chloride aqueous solution, saturated sodium bicarbonate aqueous solution, and water are added in sequence to wash until neutral, and the crude reaction product, saturated sodium chloride aqueous solution, saturated sodium bicarbonate aqueous solution, and water are washed to a mass ratio of 1:7. The ratio is 1:11:11:11, and the liquids are separated. The organic phase is taken, and anhydrous magnesium sulfate with a mass ratio of 20% of the organic phase is added for dehydration for 25 minutes. After dehydration, it is filtered, and the filtrate is taken. The solvent ethyl acetate is removed by rotary evaporation at a temperature of 55°C to obtain a reaction product. The reaction product is mixed and dissolved with ethanol at a mass ratio of 1:2.5, and water with a mass ratio of 9 times that of the reaction product is added. It is recrystallized at a temperature of 2°C for 20 hours. After recrystallization, it is filtered with suction, and the filter cake is taken. The operation of dissolving, recrystallizing, and filtering with suction is repeated once, and it is dried at a temperature of 45°C for 11 hours to obtain methacrylate vanillin ester;

[0073] The mass ratio of vanillin, dichloromethane, pyridine and methacryloyl chloride solution is 6-6.1:80-100:3.9-4:31.5-32, and the methacryloyl chloride solution is prepared by mixing and dissolving methacryloyl chloride and dichloromethane in a volume ratio of 1:4;

[0074] Step (2), mixing nano zinc oxide, γ-aminopropylmethyldiethoxysilane and ethanol in a mass ratio of 1:0.95:140, stirring and reacting at room temperature for 2.5 hours, filtering after the reaction, taking the filter cake, adding ethanol 6 times the mass of the filter cake to wash, and obtaining amino nano zinc oxide; mixing amino nano zinc oxide, ethanol and methacrylate vanillin ester in a mass ratio of 1:25:4.5, reacting at 50°C for 9 hours, filtering after the reaction, taking the filter cake, adding ethanol 6 times the mass of the filter cake to wash, and drying at 45°C for 22 hours to obtain alkenyl nano zinc oxide;

[0075] Step (3), polypropylene melt-blown resin, alkenyl nano zinc oxide, and dicumyl peroxide are mixed in a mass ratio of 100:1.4:0.45, and melt-reacted in a twin-screw extruder at a screw speed of 290 r / min and a temperature of 235° C. for 6 minutes. After the reaction is completed, melt-spinning is performed by a melt-blown spinning machine to obtain a 25.5 g / m 2 Antibacterial polypropylene meltblown fabric;

[0076] The operation of melt spinning is as follows: the antibacterial polypropylene melt is pumped into the spinneret at a temperature of 245°C, the melt pump speed is 210r / min, and the melt is stretched by hot air at a frequency of 36Hz and a temperature of 260°C, and then cooled and bonded into a web at a receiving distance of 22cm and a temperature of 8°C.

[0077] Step (4), ultrasonically treating the antibacterial polypropylene melt-blown cloth in ethanol for 25 minutes, the solid-liquid ratio of the antibacterial polypropylene melt-blown cloth to ethanol is 1:20, and drying at 55°C for 9 hours to obtain the pretreated antibacterial polypropylene melt-blown cloth; immersing the pretreated antibacterial polypropylene melt-blown cloth in a finishing liquid with a solid-liquid ratio of 1:15, stirring and reacting at room temperature for 4.5 hours, taking out after the reaction, adding water to wash until neutral, and drying at 55°C for 9 hours to obtain a modified antibacterial polypropylene melt-blown cloth; immersing the modified antibacterial polypropylene melt-blown cloth in a 0.1 mol / L silver nitrate aqueous solution, the solid-liquid ratio of the modified antibacterial polypropylene melt-blown cloth to the 0.1 mol / L silver nitrate aqueous solution is 1:55; immersing at room temperature for 9 hours, taking out after the immersion, adding water to wash until neutral, and drying at 55°C for 9 hours to obtain a silver-loaded antibacterial polypropylene melt-blown cloth;

[0078] The finishing liquid is prepared by the following steps: dopamine hydrochloride, polyethyleneimine, tris(hydroxymethyl)aminomethane) and water are mixed in a mass ratio of 1.1:1:1.2:900, and a 0.1 mol / L aqueous solution of hydrogen chloride is added to adjust the pH value to 8.3 to obtain a finishing liquid;

[0079] The antibacterial explosive beads are prepared by the following steps:

[0080] Step (1), mixing and dissolving thymol and carbon tetrachloride, adding dibenzoyl peroxide and N-bromosuccinimide, wherein the mass ratio of thymol, carbon tetrachloride, dibenzoyl peroxide and N-bromosuccinimide is 3:180:0.1:3.73, reacting at 55°C for 6-8h, and after the reaction is completed, removing the solvent carbon tetrachloride by rotary evaporation at 50°C to obtain brominated thymol; mixing brominated thymol, carbon tetrachloride and methacrylamide at a mass ratio of 1.6:190:0.62, reacting at 55°C for 5.5h, and after the reaction is completed, removing the solvent carbon tetrachloride by rotary evaporation at 50°C to obtain alkenyl thymol;

[0081] Alkenyl thymol, ethylene-vinyl acetate copolymer and dicumyl peroxide were mixed in a mass ratio of 0.9:80:0.45, and melt-reacted in a twin-screw extruder at a speed of 70 r / min and a temperature of 130° C. for 12 minutes. After the reaction was completed, the mixture was extruded and pelletized to obtain a modified ethylene-vinyl acetate copolymer;

[0082] Step (2), using the essential oil aqueous solution as the core material of the antibacterial explosive beads, the modified ethylene-vinyl acetate copolymer as the wall material of the antibacterial explosive beads, and 6 vol% ethanol aqueous solution as the coolant, and dripping the beads through a dripping pill machine to obtain the antibacterial explosive beads;

[0083] The essential oil aqueous solution is prepared by mixing water-soluble lavender essential oil, water-soluble menthol, water-soluble Millettia spatholobi extract, carboxymethyl chitosan and water in a mass ratio of 1:1:1.3:0.5:50; the temperature of the core material is 53°C, the temperature of the wall material is 93°C, the temperature of the coolant is 28°C, and the drop height is 1 cm; the water content of the antibacterial bursting beads is 80%;

[0084] Step 2: Use silver-loaded antibacterial polypropylene meltblown cloth as the upper layer material and the lower layer material respectively, place the antibacterial explosive beads between the upper layer material and the lower layer material as the middle layer material, and obtain a crude drug-loaded layer. The edges of the crude drug-loaded layer are bonded and sealed at a temperature of 110°C by a thermal bonding machine to obtain a 52.5 g / m 2 The drug loading layer;

[0085] The surface layer material, the polytetrafluoroethylene microporous membrane, the drug-carrying layer, and the inner layer material are stacked and aligned in a stacking order to obtain a rough product of a multilayer protective material. The surface layer material and the inner layer material are both polypropylene spunbonded non-woven fabrics. The gram weight of the surface layer material is 35 g / m 2 The weight of the inner layer material is 25g / m 2 ; Under pressure 240N / cm 2 , seal the edges of the rough multi-layer protective material at a temperature of 155°C to obtain a multi-layer protective material loaded with explosive beads.

[0086] Example 3

[0087] This embodiment discloses a method for preparing a multi-layer protective material loaded with explosive beads, comprising the following steps:

[0088] Step 1, preparing silver-loaded antibacterial polypropylene melt-blown cloth and antibacterial explosive beads;

[0089] The silver-loaded antibacterial polypropylene meltblown fabric is prepared by the following steps:

[0090] Step (1), vanillin and dichloromethane are mixed and dissolved, pyridine is added, methacryloyl chloride solution is added dropwise at room temperature for 40 minutes, and after the addition is completed, the reaction is carried out at 40°C for 5 hours. After the reaction is completed, the solvent dichloromethane is removed by rotary evaporation at 35°C to obtain a crude reaction product, the crude reaction product is mixed and dissolved with ethyl acetate in a mass ratio of 1:8, saturated sodium chloride aqueous solution, saturated sodium bicarbonate aqueous solution, and water are added in sequence to wash until neutral, and the crude reaction product, saturated sodium chloride aqueous solution, saturated sodium bicarbonate aqueous solution, and water are washed to neutral. The mass ratio is 1:12:12:12, and the liquids are separated. The organic phase is taken, and anhydrous magnesium sulfate with a mass ratio of 20% of the mass of the organic phase is added for dehydration for 30 minutes. After dehydration, it is filtered, and the filtrate is taken. The solvent ethyl acetate is removed by rotary evaporation at a temperature of 60°C to obtain a reaction product. The reaction product is mixed and dissolved with ethanol at a mass ratio of 1:3, and water with a mass ratio of 10 times that of the reaction product is added. It is recrystallized at a temperature of 5°C for 24 hours. After recrystallization, it is filtered by suction, and the filter cake is taken. The operation of dissolving, recrystallizing, and filtering by suction is repeated once, and it is dried at a temperature of 50°C for 10 hours to obtain methacrylic acid vanillin ester;

[0091] The mass ratio of vanillin, dichloromethane, pyridine and methacryloyl chloride solution is 6.1:100:4:32, and the methacryloyl chloride solution is prepared by mixing and dissolving methacryloyl chloride and dichloromethane in a volume ratio of 1:4.

[0092] Step (2), mixing nano zinc oxide, γ-aminopropylmethyldiethoxysilane and ethanol in a mass ratio of 1:1:150, stirring and reacting at room temperature for 3 hours, filtering after the reaction, taking the filter cake, adding ethanol 8 times the mass of the filter cake to wash, and obtaining amino nano zinc oxide; mixing amino nano zinc oxide, ethanol and methacrylate vanillin ester in a mass ratio of 1:30:5, reacting at 55°C for 8 hours, filtering after the reaction, taking the filter cake, adding ethanol 8 times the mass of the filter cake to wash, and drying at 50°C for 20 hours to obtain alkenyl nano zinc oxide;

[0093] Step (3), polypropylene melt-blown resin, alkenyl nano zinc oxide, and dicumyl peroxide are mixed in a mass ratio of 100:1.8:0.5, and melt-reacted in a twin-screw extruder at a screw speed of 300 r / min and a temperature of 240° C. for 5 minutes. After the reaction is completed, melt-spinning is performed by a melt-blown spinning machine to obtain a 26 g / m 2 Antibacterial polypropylene meltblown fabric;

[0094] The operation of melt spinning is as follows: the antibacterial polypropylene melt is pumped into the spinneret at a temperature of 250°C, the melt pump speed is 220r / min, and the melt is stretched by hot air at a frequency of 36Hz and a temperature of 260°C, and then cooled and bonded into a web at a receiving distance of 25cm and a temperature of 10°C.

[0095] Step (4), ultrasonically treating the antibacterial polypropylene melt-blown cloth in ethanol for 30 minutes, the solid-liquid ratio of the antibacterial polypropylene melt-blown cloth to ethanol is 1:20, and drying at 60°C for 8 hours to obtain the pretreated antibacterial polypropylene melt-blown cloth; immersing the pretreated antibacterial polypropylene melt-blown cloth in a finishing liquid with a solid-liquid ratio of 1:20, stirring and reacting at room temperature for 5 hours, taking out after the reaction is completed, adding water to wash until neutral, and drying at 60°C for 8 hours to obtain a modified antibacterial polypropylene melt-blown cloth; immersing the modified antibacterial polypropylene melt-blown cloth in a 0.1 mol / L silver nitrate aqueous solution, the solid-liquid ratio of the modified antibacterial polypropylene melt-blown cloth to the 0.1 mol / L silver nitrate aqueous solution is 1:60; immersing at room temperature for 10 hours, taking out after the immersion is completed, adding water to wash until neutral, and drying at 60°C for 8 hours to obtain a silver-loaded antibacterial polypropylene melt-blown cloth;

[0096] The finishing liquid is prepared by the following steps: dopamine hydrochloride, polyethyleneimine, tris(hydroxymethyl)aminomethane) and water are mixed in a mass ratio of 1.2:1:1.2:1000, and a 0.1 mol / L aqueous solution of hydrogen chloride is added to adjust the pH value to 8.5 to obtain a finishing liquid;

[0097] The antibacterial explosive beads are prepared by the following steps:

[0098] Step (1), mixing and dissolving thymol and carbon tetrachloride, adding dibenzoyl peroxide and N-bromosuccinimide, wherein the mass ratio of thymol, carbon tetrachloride, dibenzoyl peroxide and N-bromosuccinimide is 3:200:0.1:3.75, reacting at 60°C for 6h, and after the reaction is completed, removing the solvent carbon tetrachloride by rotary evaporation at 50°C to obtain brominated thymol; mixing brominated thymol, carbon tetrachloride and methacrylamide at a mass ratio of 1.6:200:0.65, reacting at 60°C for 5h, and after the reaction is completed, removing the solvent carbon tetrachloride by rotary evaporation at 50°C to obtain alkenyl thymol;

[0099] Alkenyl thymol, ethylene-vinyl acetate copolymer and dicumyl peroxide were mixed in a mass ratio of 1:80:0.5, and melt-reacted in a twin-screw extruder at a speed of 80 r / min and a temperature of 140° C. for 10 minutes. After the reaction was completed, the mixture was extruded and pelletized to obtain a modified ethylene-vinyl acetate copolymer;

[0100] Step (2), using the essential oil aqueous solution as the core material of the antibacterial explosive beads, the modified ethylene-vinyl acetate copolymer as the wall material of the antibacterial explosive beads, and 6 vol% ethanol aqueous solution as the coolant, and dripping the beads through a dripping pill machine to obtain the antibacterial explosive beads;

[0101] The essential oil aqueous solution is prepared by mixing water-soluble lavender essential oil, water-soluble menthol, water-soluble Millettia spatholobi extract, carboxymethyl chitosan and water in a mass ratio of 1:1:1.5:0.5:50; the temperature of the core material is 55°C, the temperature of the wall material is 95°C, the temperature of the coolant is 30°C, and the drop height is 1 cm; the water content of the antibacterial bursting beads is 80%;

[0102] Step 2: Use silver-loaded antibacterial polypropylene meltblown cloth as the upper layer material and the lower layer material respectively, place the antibacterial explosive beads between the upper layer material and the lower layer material as the middle layer material, and obtain a crude drug-loaded layer. The edges of the crude drug-loaded layer are bonded and sealed at 120°C by a thermal bonding machine to obtain a 53g / m 2 The drug loading layer;

[0103] The surface layer material, the polytetrafluoroethylene microporous membrane, the drug-carrying layer, and the inner layer material are stacked and aligned in a stacking order to obtain a rough product of a multilayer protective material. The surface layer material and the inner layer material are both polypropylene spunbonded non-woven fabrics. The gram weight of the surface layer material is 35 g / m 2 The weight of the inner layer material is 25g / m 2 ; Under pressure 250N / cm 2 , seal the edges of the rough multi-layer protective material at a temperature of 160°C to obtain a multi-layer protective material loaded with explosive beads.

[0104] Example 4

[0105] This embodiment discloses a method for preparing a multi-layer protective mask loaded with explosive beads, comprising the following steps:

[0106] The multi-layer protective material loaded with bursting beads prepared in Example 1-3 is used as the main material of the mask, cut according to size to obtain a mask body, and the mask body is connected and compounded with ear ropes to obtain a multi-layer protective mask loaded with bursting beads, which is recorded as sample 1-3.

[0107] Comparative Example 1

[0108] This comparative example discloses a method for preparing a multi-layer protective material loaded with explosive beads, comprising the following steps:

[0109] Step 1, preparing silver-loaded polypropylene melt-blown cloth and antibacterial explosive beads;

[0110] The silver-loaded polypropylene meltblown cloth is prepared by the following steps:

[0111] The polypropylene melt-blown resin was melted in a twin-screw extruder at a screw speed of 280 r / min and a temperature of 230°C for 8 min, and melt-spun by a melt-blown spinning machine to obtain a 25 g / m 2 Polypropylene meltblown cloth;

[0112] The operation of melt spinning is as follows: the polypropylene melt is pumped into the spinneret at a temperature of 240°C, the melt pump speed is 200r / min, and the melt is stretched by hot air at a frequency of 36Hz and a temperature of 260°C, and then cooled and bonded into a web at a receiving distance of 20cm and a temperature of 5°C;

[0113] The polypropylene melt-blown cloth was ultrasonically treated in ethanol for 20 minutes, the solid-liquid ratio of the polypropylene melt-blown cloth to the ethanol was 1:20, and it was dried at 50°C for 10 hours to obtain the pretreated polypropylene melt-blown cloth; the pretreated polypropylene melt-blown cloth was immersed in the finishing liquid, the solid-liquid ratio was 1:10, stirred and reacted at room temperature for 4 hours, taken out after the reaction, washed with water until neutral, and dried at 50°C for 10 hours to obtain the modified polypropylene melt-blown cloth; the modified polypropylene melt-blown cloth was immersed in a 0.1 mol / L silver nitrate aqueous solution, the solid-liquid ratio of the modified polypropylene melt-blown cloth to the 0.1 mol / L silver nitrate aqueous solution was 1:50; immersed at room temperature for 8 hours, taken out after the immersion, washed with water until neutral, and dried at 50°C for 10 hours to obtain the silver-loaded polypropylene melt-blown cloth;

[0114] The finishing liquid is prepared by the following steps: dopamine hydrochloride, polyethyleneimine, tris(hydroxymethyl)aminomethane) and water are mixed in a mass ratio of 1:1:1.2:800, and a 0.1 mol / L aqueous solution of hydrogen chloride is added to adjust the pH value to 8 to obtain a finishing liquid;

[0115] The antibacterial explosive beads are prepared by the following steps:

[0116] Step (1), mixing and dissolving thymol and carbon tetrachloride, adding dibenzoyl peroxide and N-bromosuccinimide, wherein the mass ratio of thymol, carbon tetrachloride, dibenzoyl peroxide and N-bromosuccinimide is 3:160:0.1:3.7, reacting at 50°C for 8h, and after the reaction is completed, removing the solvent carbon tetrachloride by rotary evaporation at 50°C to obtain brominated thymol; mixing brominated thymol, carbon tetrachloride and methacrylamide at a mass ratio of 1.6:180:0.6, reacting at 50°C for 6h, and after the reaction is completed, removing the solvent carbon tetrachloride by rotary evaporation at 50°C to obtain alkenyl thymol;

[0117] Alkenyl thymol, ethylene-vinyl acetate copolymer and dicumyl peroxide were mixed in a mass ratio of 0.8:80:0.4, and melt-reacted in a twin-screw extruder at a speed of 60 r / min and a temperature of 120° C. for 15 minutes. After the reaction was completed, the mixture was extruded and pelletized to obtain a modified ethylene-vinyl acetate copolymer;

[0118] Step (2), using the essential oil aqueous solution as the core material of the antibacterial explosive beads, the modified ethylene-vinyl acetate copolymer as the wall material of the antibacterial explosive beads, and 6 vol% ethanol aqueous solution as the coolant, and dripping the beads through a dripping pill machine to obtain the antibacterial explosive beads;

[0119] The essential oil aqueous solution is prepared by mixing water-soluble lavender essential oil, water-soluble menthol, water-soluble Millettia spatholobi extract, carboxymethyl chitosan and water in a mass ratio of 1:1:1:0.5:50; the temperature of the core material is 50°C, the temperature of the wall material is 90°C, the temperature of the coolant is 25°C, and the drop height is 1 cm; the water content of the antibacterial bursting beads is 80%;

[0120] Step 2: Use silver-loaded polypropylene meltblown cloth as the upper layer material and the lower layer material respectively, place antibacterial explosive beads between the upper layer material and the lower layer material as the middle layer material, and obtain a crude drug-loaded layer. Use a thermal bonding machine to bond and seal the edges of the crude drug-loaded layer at a temperature of 100°C to obtain a 52g / m 2 The drug loading layer;

[0121] The surface layer material, the polytetrafluoroethylene microporous membrane, the drug-carrying layer, and the inner layer material are stacked and aligned in a stacking order to obtain a rough product of a multilayer protective material. The surface layer material and the inner layer material are both polypropylene spunbonded non-woven fabrics. The gram weight of the surface layer material is 35 g / m 2 The weight of the inner layer material is 25g / m 2 ; Under pressure 220N / cm 2 , seal the edges of the rough multi-layer protective material at a temperature of 150°C to obtain a multi-layer protective material loaded with explosive beads.

[0122] Comparative Example 2

[0123] This embodiment discloses a method for preparing a multi-layer protective material loaded with explosive beads, comprising the following steps:

[0124] Step 1, preparing antibacterial polypropylene melt-blown cloth and antibacterial explosive beads;

[0125] Among them, the antibacterial polypropylene meltblown cloth is prepared by the following steps:

[0126] Polypropylene melt-blown resin, alkenyl nano zinc oxide, and dicumyl peroxide were mixed in a mass ratio of 100:1:0.4, and melt-reacted in a twin-screw extruder at a screw speed of 280 r / min and a temperature of 230°C for 8 minutes. After the reaction, the melt was spun by a melt-blown spinning machine to obtain a 25 g / m 2 Antibacterial polypropylene meltblown fabric;

[0127] The preparation of alkenyl nano zinc oxide is the same as that in Example 1; the operation of melt spinning is as follows: the antibacterial polypropylene melt is pumped into the spinneret at a temperature of 240°C, the melt pump speed is 200r / min, and the melt is stretched by hot air at a frequency of 36Hz and a temperature of 260°C, and then cooled and bonded into a web at a receiving distance of 20cm and a temperature of 5°C;

[0128] The antibacterial explosive beads are prepared by the following steps:

[0129] Step (1), mixing and dissolving thymol and carbon tetrachloride, adding dibenzoyl peroxide and N-bromosuccinimide, wherein the mass ratio of thymol, carbon tetrachloride, dibenzoyl peroxide and N-bromosuccinimide is 3:160:0.1:3.7, reacting at 50°C for 8h, and after the reaction is completed, removing the solvent carbon tetrachloride by rotary evaporation at 50°C to obtain brominated thymol; mixing brominated thymol, carbon tetrachloride and methacrylamide at a mass ratio of 1.6:180:0.6, reacting at 50°C for 6h, and after the reaction is completed, removing the solvent carbon tetrachloride by rotary evaporation at 50°C to obtain alkenyl thymol;

[0130] Alkenyl thymol, ethylene-vinyl acetate copolymer and dicumyl peroxide were mixed in a mass ratio of 0.8:80:0.4, and melt-reacted in a twin-screw extruder at a speed of 60 r / min and a temperature of 120° C. for 15 minutes. After the reaction was completed, the mixture was extruded and pelletized to obtain a modified ethylene-vinyl acetate copolymer;

[0131] Step (2), using the essential oil aqueous solution as the core material of the antibacterial explosive beads, the modified ethylene-vinyl acetate copolymer as the wall material of the antibacterial explosive beads, and 6 vol% ethanol aqueous solution as the coolant, and dripping the beads through a dripping pill machine to obtain the antibacterial explosive beads;

[0132] The essential oil aqueous solution is prepared by mixing water-soluble lavender essential oil, water-soluble menthol, water-soluble Millettia spatholobi extract, carboxymethyl chitosan and water in a mass ratio of 1:1:1:0.5:50; the temperature of the core material is 50°C, the temperature of the wall material is 90°C, the temperature of the coolant is 25°C, and the drop height is 1 cm; the water content of the antibacterial bursting beads is 80%;

[0133] Step 2: Use antibacterial polypropylene meltblown cloth as the upper layer material and the lower layer material respectively, place the antibacterial explosive beads between the upper layer material and the lower layer material as the middle layer material, and obtain a crude drug-carrying layer. The edges of the crude drug-carrying layer are bonded and sealed at 100°C by a thermal bonding machine to obtain a 52g / m 2 The drug loading layer;

[0134] The surface layer material, the polytetrafluoroethylene microporous membrane, the drug-carrying layer, and the inner layer material are stacked and aligned in a stacking order to obtain a rough product of a multilayer protective material. The surface layer material and the inner layer material are both polypropylene spunbonded non-woven fabrics. The gram weight of the surface layer material is 35 g / m 2 The weight of the inner layer material is 25g / m 2 ; Under pressure 220N / cm 2 , seal the edges of the rough multi-layer protective material at a temperature of 150°C to obtain a multi-layer protective material loaded with explosive beads.

[0135] Comparative Example 3

[0136] This comparative example discloses a method for preparing a multi-layer protective mask loaded with explosive beads, comprising the following steps:

[0137] The multi-layer protective material loaded with bursting beads prepared in Comparative Example 1-2 is used as the main material of the mask, and is cut according to size to obtain a mask body. The mask body is connected and compounded with ear ropes to obtain a multi-layer protective mask loaded with bursting beads, which is recorded as sample 4-5.

[0138] In the above embodiments and comparative examples: vanillin comes from Shanghai Aladdin Biochemical Technology Co., Ltd., CAS No.: 121-33-5; methacryloyl chloride comes from Shanghai McLean Biochemical Technology Co., Ltd., CAS No.: 920-46-7; polypropylene melt-blown resin comes from China Chemical Group Co., Ltd., with a melt flow index of 1500 g / min; dopamine hydrochloride comes from AlfaAesar, CAS No.: 62-31-7; polyethyleneimine comes from Shanghai McLean Biochemical Technology Co., Ltd., Mw=5000, CAS No.: 9002-98-6; carboxymethyl chitosan comes from Shanghai McLean Biochemical Technology Co., Ltd., with a molecular weight of 240Kda, a deacetylation degree of 90%, a substitution degree of 90%, CAS No.: 83512-85-0; ethylene-vinyl acetate copolymer comes from Shanghai Aladdin Biochemical Technology Co., Ltd., and the melt viscosity at 90°C is 200 MPa / s -1 ; Water-soluble lavender essential oil comes from Ji'an Zhongda Natural Plant Flavor Co., Ltd., product name water-soluble lavender oil, refractive index 1.457; water-soluble menthol comes from Shandong Binzhou Zhiyuan Biotechnology Co., Ltd., product name water-soluble menthol cyclodextrin inclusion complex; water-soluble Millettia reticulata extract comes from Shaanxi Snot Biotechnology Co., Ltd., specification 80 mesh, active ingredient content 90%; polytetrafluoroethylene microporous membrane comes from Changzhou Jinchun Environmental Protection Technology Co., Ltd., thickness 0.1mm, average pore size 3.2μm, porosity 88%.

[0139] Test example

[0140] The antibacterial performance of the multi-layer protective materials loaded with burst beads prepared in Examples 1-3 and Comparative Examples 1-2 was tested, and the comprehensive performance of the multi-layer protective mask samples 1-5 loaded with burst beads prepared in Example 4 and Comparative Example 3 was tested. The specific test results are shown in Tables 1 and 2:

[0141] Table 1

[0142] Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Antibacterial rate (%) 99.82 99.88 99.95 98.76 98.23

[0143] Table 2

[0144]

[0145] The detection of each indicator in Table 1 and Table 2 is based on the following standards: the antibacterial rate is determined with reference to GB / T 20944.3-2008 "Evaluation of Antibacterial Properties of Textiles", and Escherichia coli is selected as the bacteria; the inhalation resistance, exhalation resistance and filtration efficiency are all determined with reference to GB / T32610-2016 "Technical Specifications for Daily Protective Masks", and the filtration efficiency test is graded as Level 2.

[0146] According to the test results in Table 1, it can be seen that the multi-layer protective material loaded with bursting beads prepared by the present invention has excellent antibacterial properties, and the mask prepared therefrom meets the standards and has good filtration performance.

[0147] By preparing alkenyl nano zinc oxide with active group carbon-carbon double bonds and organic-inorganic synergistic antibacterial, and mixing and melting with polypropylene melt-blown resin, alkenyl nano zinc oxide is grafted on the main chain of polypropylene resin, further improving the dispersibility and compatibility of nano zinc oxide in the system, and the obtained antibacterial polypropylene melt-blown cloth has better antibacterial properties; the antibacterial polypropylene melt-blown cloth is pre-treated and then immersed in a finishing liquid, in which polyethyleneimine as a cross-linking agent can react with dopamine to form a cross-linked network, and a polydopamine / polyethyleneimine modified layer can be quickly formed on the surface of the melt-blown cloth. After the modified antibacterial polypropylene melt-blown cloth is immersed in a silver nitrate solution, the silver ions can be reduced to silver element due to the reducing effect of polydopamine. At the same time, the active groups of polydopamine and polyethyleneimine can fix silver particles, making them not easy to fall off, further improving the antibacterial properties of the polypropylene melt-blown cloth;

[0148] As a melt-blown nonwoven material, polypropylene meltblown cloth has the advantages of fine fiber diameter, small pore size, large specific surface area, and small filtration resistance. It is widely used in air filtration materials. By preparing silver-loaded antibacterial polypropylene meltblown cloth with excellent antibacterial properties, and compounding it with the surface material, polytetrafluoroethylene microporous membrane, and inner layer material, the obtained multi-layer protective material loaded with burst beads constitutes a spunbond-meltblown-spunbond structure, which has excellent antibacterial ability and filtration performance. It is used as the main material of the mask, and the mask obtained has good antibacterial and filtration properties.

[0149] In the silver-loaded polypropylene meltblown cloth of Comparative Example 1, olefinic zinc oxide is not added, and the synergistic antibacterial effect of the organic antibacterial structure and the inorganic antibacterial agent is lacking, so the antibacterial property of Comparative Example 1 is lower than that of the embodiment; in Comparative Example 2, the antibacterial polypropylene meltblown cloth is not surface modified, and silver particles are not loaded, and the effect of silver element on improving the antibacterial properties of the polypropylene meltblown cloth is lacking, so the antibacterial property of Comparative Example 2 is lower than that of the embodiment.

[0150] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a multi-layer protective material loaded with explosive beads, characterized in that: The following steps are involved: Step 1, preparing silver-loaded antibacterial polypropylene melt-blown cloth and antibacterial explosive beads; The silver-loaded antibacterial polypropylene meltblown fabric is prepared by the following steps: Step (1), mixing polypropylene melt-blown resin, alkenyl nano zinc oxide, and dicumyl peroxide, melting and reacting, and after the reaction is completed, melt spinning to obtain an antibacterial polypropylene melt-blown cloth; Wherein, the alkenyl nano zinc oxide is prepared by the following steps: S11, mixing and dissolving vanillin and dichloromethane, adding pyridine, and dropping methacryloyl chloride solution at room temperature, reacting after the dropping is complete, and after the reaction is complete, removing the solvent dichloromethane by rotary evaporation, purifying, recrystallizing, and drying to obtain methacrylic vanillin ester; S12, mixing nano zinc oxide, γ-aminopropylmethyldiethoxysilane and ethanol, reacting, filtering and washing after the reaction to obtain amino nano zinc oxide; mixing amino nano zinc oxide, ethanol and methacrylate vanillin ester, reacting, filtering, washing and drying after the reaction to obtain alkenyl nano zinc oxide; Step (2), ultrasonically treating the antibacterial polypropylene melt-blown fabric in ethanol, and drying to obtain a pretreated antibacterial polypropylene melt-blown fabric; immersing the pretreated antibacterial polypropylene melt-blown fabric in a finishing liquid, reacting, taking out after the reaction, washing, and drying to obtain a modified antibacterial polypropylene melt-blown fabric; Wherein, the finishing liquid is prepared by the following steps: Dopamine hydrochloride, polyethyleneimine, tris(hydroxymethyl)aminomethane) and water are mixed, and a regulator is added to adjust the pH value to obtain a finishing solution; The modified antibacterial polypropylene melt-blown fabric is immersed in a silver nitrate aqueous solution, and after the immersion is completed, the fabric is taken out, washed, and dried to obtain a silver-loaded antibacterial polypropylene melt-blown fabric; The antibacterial explosive beads are prepared by the following steps: The thymol and carbon tetrachloride are mixed and dissolved, dibenzoyl peroxide and N-bromosuccinimide are added, and the reaction is carried out. After the reaction is completed, the solvent carbon tetrachloride is removed by rotary evaporation to obtain bromothymol; the bromothymol, carbon tetrachloride and methacrylamide are mixed, and the reaction is carried out. After the reaction is completed, the solvent carbon tetrachloride is removed by rotary evaporation to obtain alkenylthymol; The modified ethylene-vinyl acetate copolymer is obtained by mixing alkenyl thymol, ethylene-vinyl acetate copolymer and dicumyl peroxide, and performing a melt reaction. After the reaction is completed, the mixture is extruded and pelletized. The essential oil aqueous solution is used as the core material of the antibacterial explosive beads, the modified ethylene-vinyl acetate copolymer is used as the wall material of the antibacterial explosive beads, the ethanol aqueous solution is used as the coolant, and the antibacterial explosive beads are obtained by dropping pills in a pill dropping machine; Step 2: silver-loaded antibacterial polypropylene meltblown cloth is used as the upper layer material and the lower layer material respectively, and antibacterial explosive beads are placed between the upper layer material and the lower layer material as the middle layer material to obtain a crude drug-loaded layer, and the edges of the crude drug-loaded layer are bonded and sealed to obtain a drug-loaded layer; The surface layer material, polytetrafluoroethylene microporous membrane, drug-carrying layer and inner layer material are stacked and aligned in a stacking order to obtain a rough multi-layer protective material. The surface layer material and the inner layer material are both polypropylene spunbond non-woven fabrics. The edges of the rough multi-layer protective material are sealed to obtain a multi-layer protective material loaded with explosive beads.

2. The method for preparing a multi-layer protective material loaded with explosive beads according to claim 1, characterized in that: When preparing the silver-loaded antibacterial polypropylene melt-blown cloth in step 1, in the preparation of alkenyl nano zinc oxide in step (1): In S11, the mass ratio of vanillin, dichloromethane, pyridine and methacryloyl chloride solution is 6-6.1:80-100:3.9-4:31.5-32, and the methacryloyl chloride solution is prepared by mixing and dissolving methacryloyl chloride and dichloromethane in a volume ratio of 1:4; the dropping condition is: dropping at room temperature for 30-40 minutes; the reaction condition is: reacting at a temperature of 35-40°C for 5-8 hours; In S12: the mass ratio of nano zinc oxide, γ-aminopropylmethyldiethoxysilane, and ethanol is 1:0.9-1:120-150; when preparing amino nano zinc oxide, the reaction conditions are: stirring the reaction at room temperature for 2-3 hours; the mass ratio of amino nano zinc oxide, ethanol, and vanillin methacrylate is 1:20-30:4-5; when preparing alkenyl nano zinc oxide, the reaction conditions are: reacting at a temperature of 45-55°C for 8-10 hours.

3. The method for preparing a multi-layer protective material loaded with explosive beads according to claim 1, characterized in that: When preparing the silver-loaded antibacterial polypropylene melt-blown cloth in step (1), the mass ratio of polypropylene melt-blown resin, alkenyl nano zinc oxide, and dicumyl peroxide is 100:1-1.8:0.4-0.5; the melting reaction conditions are: in a twin-screw extruder, the screw speed is 280-300r / min, and the temperature is 230-240°C, and the melting reaction is carried out for 5-8min; the melt spinning operation is: the antibacterial polypropylene melt is pumped into the spinneret at a temperature of 240-250°C, the melt pump speed is 200-220r / min, and the antibacterial polypropylene melt is stretched by hot air at a frequency of 36Hz and a temperature of 260°C, and then cooled and bonded into a web at a receiving distance of 20-25cm and a temperature of 5-10°C; the gram weight of the antibacterial polypropylene melt-blown cloth is 25-26g / m 2 .

4. The method for preparing a multi-layer protective material loaded with explosive beads according to claim 1, characterized in that: When preparing the silver-loaded antibacterial polypropylene meltblown fabric in step 1, in the preparation of the finishing liquid in step (2): The mass ratio of dopamine hydrochloride, polyethyleneimine, tris(hydroxymethyl)aminomethane) and water is 1-1.2:1:1.2:800-1000; the adjusted pH value is 8-8.

5.

5. The method for preparing a multi-layer protective material loaded with explosive beads according to claim 1, characterized in that: When preparing the silver-loaded antibacterial polypropylene melt-blown cloth in step 1, in step (2): the solid-liquid ratio of the antibacterial polypropylene melt-blown cloth to ethanol is 1:20; the solid-liquid ratio of the pretreated antibacterial polypropylene melt-blown cloth to the finishing liquid is 1:10-20; the reaction conditions are: stirring the reaction at room temperature for 4-5 hours; the solid-liquid ratio of the modified antibacterial polypropylene melt-blown cloth to the silver nitrate aqueous solution is 1:50-60, and the silver nitrate aqueous solution is a 0.1 mol / L silver nitrate aqueous solution; and the immersion conditions are: immersing at room temperature for 8-10 hours.

6. The method for preparing a multi-layer protective material loaded with explosive beads according to claim 1, characterized in that: When preparing antibacterial explosive beads in step 1: The mass ratio of thymol, carbon tetrachloride, dibenzoyl peroxide, and N-bromosuccinimide is 3:160-200:0.1:3.7-3.75; when preparing bromothymol, the reaction conditions are: reacting at a temperature of 50-60°C for 6-8h; the mass ratio of bromothymol, carbon tetrachloride, and methacrylamide is 1.6:180-200:0.6-0.65; when preparing alkenylthymol, the reaction conditions are: reacting at a temperature of 50-60°C for 5-6h; The mass ratio of alkenyl thymol, ethylene-vinyl acetate copolymer and dicumyl peroxide is 0.8-1:80:0.4-0.5; the melting reaction conditions are: in a twin-screw extruder, the speed is 60-80r / min, the temperature is 120-140°C, and the melting reaction is carried out for 10-15min.

7. The method for preparing a multi-layer protective material loaded with explosive beads according to claim 1, characterized in that: In the step 1, when preparing the antibacterial bursting beads: the essential oil aqueous solution is prepared by mixing water-soluble lavender essential oil, water-soluble menthol, water-soluble Millettia spatholobi extract, carboxymethyl chitosan and water in a mass ratio of 1:1:1-1.5:0.5:50; the temperature of the core material is 50-55°C, the temperature of the wall material is 90-95°C, the concentration of the ethanol aqueous solution is 6 vol%, the temperature of the coolant is 25-30°C, and the drop height is 1 cm; the water content of the antibacterial bursting beads is 80%.

8. The method for preparing a multi-layer protective material loaded with explosive beads according to claim 1, characterized in that: In step 2: the weight of the drug-carrying layer is 52-53 g / m 2 When preparing multi-layer protective materials containing explosive beads, the weight of the surface material is 35g / m 2 The weight of the inner layer material is 25g / m 2 Sealing conditions: at a pressure of 220-250N / cm 2 , seal the edges of the rough multi-layer protective material at a temperature of 150-160°C.

9. A multi-layer protective material loaded with explosive beads prepared by the method for preparing a multi-layer protective material loaded with explosive beads as described in any one of claims 1 to 8.

10. A multi-layer protective mask loaded with bursting beads prepared based on the multi-layer protective material loaded with bursting beads as claimed in any one of claims 1 to 8.

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