Composite fabric with electromagnetic shielding effectiveness, preparation method and application

Abstract

The invention relates to the field of layered composite fabrics, and discloses a composite fabric with electromagnetic shielding effectiveness, a preparation method and application. The preparation method comprises the following steps: preparing an electromagnetic shielding coating, fixing the electromagnetic shielding coating on the surface of a modified nylon 66 fabric through a thiol-ene click reaction to obtain an electromagnetic shielding fabric, taking the electromagnetic shielding fabric as an inner layer of the composite fabric, and compounding the inner layer, a middle layer polyester film and a surface layer aluminum rolled material through a polyurethane hot melt adhesive to obtain the composite fabric. The obtained composite fabric has low-reflection and high-absorption electromagnetic shielding effectiveness, and can be applied to tents.

Description

Technical Field

[0001] The invention relates to the field of layered composite fabrics, and in particular to a composite fabric with electromagnetic shielding performance, a preparation method and application thereof. Background Art

[0002] In recent years, the rapid development of intelligent interactive products and wireless communication technology has led to the widespread emergence of artificial electromagnetic radiation sources, and the energy level has been continuously rising in the increasingly rapid growth. Under the conditions of limited space and limited frequency, the space electromagnetic energy has increased by 10% per year. The intricate electric radiation network thus formed will cover a large number of people engaged in related work and ordinary people. The electromagnetic interference radiation with increasing energy and density will not only affect the normal operation of high-precision electronic equipment, but also affect human health, increasing the risk of headaches, immunodeficiency and other diseases for related personnel. Therefore, it is urgent to take effective measures to prevent or reduce a series of problems caused by electromagnetic interference.

[0003] Electromagnetic interference mainly comes from electromagnetic induction, and the main body that produces electromagnetic induction is the electromagnetic interference radiation source. At present, the protection against electromagnetic radiation mainly relies on controlling the radiation source, distance protection and shielding protection. Although people can stay away from the radiation source to achieve self-protection, in actual work and life, the radiation source is almost everywhere, and people cannot avoid being exposed to a wide range of electromagnetic radiation pollution. Even if a certain distance is maintained, the impact of radiation cannot be completely eliminated. Therefore, good shielding protection is the most effective means to prevent electromagnetic interference and achieve human protection. Generally, shielding is to cut off or block the electromagnetic field coupling path by conductive or magnetic shielding materials, thereby limiting electromagnetic radiation to a specified space range. Among many shielding materials, flexible electromagnetic shielding materials based on textiles are an emerging flexible electromagnetic compatibility material that not only has excellent electromagnetic shielding properties, but also maintains the softness, breathability, comfort, fatigue resistance and easy cutting properties of the textile itself.

[0004] However, the current fabric-based electromagnetic shielding materials are mainly composed of inorganic shielding materials and organic fiber materials. Although they can give textiles certain electromagnetic shielding functions, the weak interface bonding between the inorganic shielding layer and the organic fiber makes it easy to fall off, break the conductive path, and cannot effectively and evenly absorb electromagnetic waves in practical applications, making it difficult to use them for a long time. In addition, the existing electromagnetic shielding fabrics mainly give textiles electromagnetic shielding functions by improving conductivity. The shielding mechanism is mainly reflection, and it cannot eliminate electromagnetic radiation from the source. Therefore, how to overcome the above problems in the application of electromagnetic shielding fabrics and develop high-performance electromagnetic shielding fabrics with low reflection, high absorption, and excellent bonding strength between the functional layer and the fabric base has important practical and research significance.

[0005] Prior art, such as Chinese patent application CN109334183A, discloses an electromagnetic shielding composite material, including an electromagnetic absorption layer, an electromagnetic reflection layer and a release material layer, characterized in that: the absorption layer includes 12-15 parts of conductive filler and 40-45 parts of matrix filler by weight; the electromagnetic reflection layer includes 25-30 parts of fiber bottom layer and 50-55 parts of rubber matrix filler; the release material is a release paper layer or a release film layer. This composite material mainly imparts electromagnetic shielding function by improving conductivity, and the shielding mechanism is mainly reflection, which is easy to cause secondary electromagnetic pollution. Summary of the invention

[0006] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a composite fabric with electromagnetic shielding performance and a preparation method thereof. The composite fabric has electromagnetic shielding performance with low reflection and high absorption.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is as follows: A method for preparing a composite fabric with electromagnetic shielding performance comprises the following steps: Step (1), preparing an electromagnetic shielding coating; S11, mixing 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin, potassium thioacetate and N,N-dimethylformamide, and reacting them. After the reaction is completed, extracting, drying, and filtering to obtain an intermediate product; The intermediate product, 30 wt% sodium methoxide methanol solution and tetrahydrofuran are mixed and reacted, and after the reaction is completed, the pH is neutralized, washed, dried, and filtered to obtain a modified thiophene monomer; S12, mixing graphene oxide with 1 mol / L sulfuric acid aqueous solution, ultrasonically dispersing, adding modified thiophene monomer, ultrasonically dispersing, stirring, adding ammonium persulfate, reacting, filtering, washing, and drying after the reaction to obtain a graphene oxide / modified polythiophene composite material; The graphene oxide / modified polythiophene composite material is mixed with water, ultrasonically dispersed, nickel nitrate and iron nitrate are added, stirred, pH is adjusted, reacted, and after the reaction is completed, filtered, washed, and dried to obtain an electromagnetic shielding additive; S13, mixing the electromagnetic shielding additive with the waterborne polyurethane acrylate, adding 2,2-dimethoxy-2-phenylacetophenone, and stirring, and obtaining an electromagnetic shielding coating after the stirring is completed; Step (2), mixing nylon 66 fabric, 3-mercaptopropyltriethoxysilane (MPTES) and a mixed solvent of ethanol and water, adjusting the pH, reacting, and after the reaction is completed, washing and drying to obtain a modified nylon 66 fabric; The electromagnetic shielding coating is applied on both sides of the modified nylon 66 fabric, reacted, and after the reaction is completed, dried to obtain the electromagnetic shielding fabric; Step (3), using the electromagnetic shielding fabric as the inner layer, the aluminum rolled material as the surface layer, and the polyester film as the middle layer, coating polyurethane hot melt adhesive on both sides thereof, placing the electromagnetic shielding fabric and the aluminum rolled material on both sides of the middle layer respectively, and hot pressing to obtain a composite fabric with electromagnetic shielding performance.

[0008] Preferably, in step (1), when preparing the electromagnetic shielding coating, in S11: the mass ratio of 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin, potassium thioacetate, and N,N-dimethylformamide is 5:(5-6):(25-35); when preparing the intermediate product, the reaction conditions are: reacting at a temperature of 45-55°C for 14-16h; the mass ratio of the intermediate product, 30wt% sodium methoxide methanol solution, and tetrahydrofuran is 2:(4-8):(140-160); when preparing the modified thiophene monomer, the reaction conditions are: reacting in a nitrogen atmosphere at room temperature for 4-6h.

[0009] Preferably, in the step (1), when preparing the electromagnetic shielding coating, in S12: the mass ratio of graphene oxide, 1 mol / L sulfuric acid aqueous solution, modified thiophene monomer, and ammonium persulfate is 0.1:(120-160):(0.25-0.45):(0.8-1); when preparing the graphene oxide / modified polythiophene composite material, the reaction conditions are: react at a temperature of 0-5°C for 20-24h; the mass ratio of the graphene oxide / modified polythiophene composite material, water, nickel nitrate, and iron nitrate is 0.2:(180-200):(0.3-0.5):(0.8-1.2); when preparing the electromagnetic shielding additive, the reaction conditions are: react at pH=10-11 and a temperature of 180-200°C for 10-12h.

[0010] Preferably, in the step (1), when preparing the electromagnetic shielding coating, in S13: the mass ratio of the electromagnetic shielding additive, the water-based polyurethane acrylate, and the 2,2-dimethoxy-2-phenylacetophenone is (0.5-2):100:(0.5-0.7); and the stirring conditions are: stirring at a speed of 600-700 rpm for 30-50 min under light-proof conditions.

[0011] Preferably, when preparing the electromagnetic shielding coating, the water-based polyurethane acrylate is prepared by the following steps: mixing isophorone diisocyanate (IPDI) and polyethylene glycol, stirring, adding dibutyltin dilaurate, reacting, adding 2,2-dihydroxymethylpropionic acid (DMPA) after the reaction, continuing the reaction, adding 2-hydroxyethyl methacrylate (HEMA) after the reaction, reacting again, adding triethylamine after the reaction, neutralizing, emulsifying, stirring, and obtaining water-based polyurethane acrylate.

[0012] Furthermore, the mass ratio of isophorone diisocyanate (IPDI), polyethylene glycol, dibutyltin dilaurate, 2,2-dihydroxymethylpropionic acid (DMPA), 2-hydroxyethyl methacrylate (HEMA), and triethylamine is 7:(5.5-6.5):(0.05-0.1):(1.1-1.3):(1.8-2):(0.8-1); the reaction conditions are: react at 60-70°C for 1-2h; the continued reaction conditions are: continue to react at 80-90°C for 3-5h; the second reaction conditions are: react again at 70-80°C for 4-6h; the neutralization reaction conditions are: neutralize at room temperature for 0.5-1h; the solid content after emulsification is controlled at 40-50wt%.

[0013] Preferably, in step (2), when preparing the modified nylon 66 fabric: the mass ratio of nylon 66 fabric, 3-mercaptopropyltriethoxysilane (MPTES) and mixed solvent is 1:(8-12):(160-200); the volume ratio of ethanol to water in the mixed solvent is 9:1; and the reaction conditions are: reaction at pH = 4-5 and temperature of 60-80°C for 2-3h.

[0014] Preferably, in step (2), when preparing the electromagnetic shielding fabric: the single-side coating amount of the electromagnetic shielding coating is 25-45 g / m 2 ; The reaction conditions are: react for 30-50 minutes under 350-370nm ultraviolet light irradiation.

[0015] Preferably, in step (3), when preparing the composite fabric with electromagnetic shielding performance: the glue amount of the inner layer electromagnetic shielding fabric and the middle layer polyester film and the glue amount of the surface layer aluminum calendering material and the middle layer polyester film are both 15-25g / m 2 ; Hot pressing conditions: 125-135℃ temperature, 2-2.5N·cm -2 Heat press under pressure for 60-80s.

[0016] Preferably, a composite fabric with electromagnetic shielding effectiveness is prepared by the method for preparing a composite fabric with electromagnetic shielding effectiveness as described above.

[0017] Preferably, a composite fabric with electromagnetic shielding performance as described above is used in a tent.

[0018] Compared with the prior art, the present invention has the following beneficial effects: The unique two-dimensional structure of graphene gives it a large specific surface area, which can promote the scattering and multiple reflections of electromagnetic waves, resulting in more microwave absorption and improving electromagnetic shielding effectiveness; nickel ferrite has the characteristics of wide raw material sources, good dispersibility, low cost and excellent magnetic properties, such as domain wall resonance, natural resonance and hysteresis loss. The present invention combines the in-situ polymerization method with the hydrothermal method, and uses conductive polymer modified polythiophene and magnetic nickel ferrite to jointly modify graphene. The interface polarization generated by the prepared electromagnetic shielding additive under the action of the external electric field helps to improve the dielectric loss of the material, and the impedance matching between dielectric loss and magnetic loss, the interface polarization generated by the multilayer interface, and the electronic polarization and dipole polarization in the magnetic nanoparticles can all improve the wave absorption performance of the composite fabric, thereby improving its electromagnetic shielding effectiveness.

[0019] At the same time, the present invention achieves the goal of reducing the reflected shielding effectiveness value while increasing the total shielding effectiveness value by doping the conductive network with magnetic properties. When the nanomagnetic metal interacts with electromagnetic waves, interface polarization and multiple scattering will consume the electromagnetic waves. Therefore, the introduction of magnetic nickel ferrite mainly enhances the shielding effectiveness of the composite fabric against electromagnetic waves by improving the absorption effect, and there is a significant synergistic effect between the electric and magnetic components, demonstrating a shielding mechanism dominated by absorption, thereby reducing secondary pollution of electromagnetic waves.

[0020] In addition, the present invention uses graphene and modified polythiophene as electrical components and nickel ferrite as magnetic component, which are mixed with olefin-terminated water-based polyurethane acrylate to obtain an electromagnetic shielding coating, and uses a mercapto-olefin click reaction to construct a conductive and magnetic dual-effect structure on the surface of the modified nylon 66 fabric. This can not only improve the bonding strength between the coating functional layer and the fabric substrate by covalent bonding, effectively avoid problems such as functional layer shedding and conductive path breakage, but also better retain the mechanical flexibility, thermal stability and air permeability of the fabric substrate. The prepared composite fabric still has typical textile stretching-fracture characteristics, and the construction of the fabric's external functional layer improves the overall breaking strength and elongation at break of the electromagnetic shielding fabric.

[0021] The present invention sequentially compounds electromagnetic shielding fabric, polyurethane hot melt adhesive, polyester film, polyurethane hot melt adhesive, and aluminum calendering material, and hot presses to obtain composite fabric. Among them, the aluminum calendering material has excellent electrical conductivity and shielding performance, and is an important barrier for electromagnetic shielding, which can ensure the stability of the entire fabric in a complex electromagnetic environment, but the aluminum calendering material is easily damaged, so a layer of polyester film is compounded on one side of the aluminum calendering material to enhance its wear resistance and tear resistance, and then the electromagnetic shielding fabric is compounded on the side of the polyester film without the aluminum calendering material, thereby enhancing the stability of the composite fabric and improving its electromagnetic shielding efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1It is a process flow chart for preparing a composite fabric with electromagnetic shielding performance in the present invention; Figure 2 It is a schematic structural diagram of a composite fabric with electromagnetic shielding performance prepared in the present invention; Figure 3 is a bar graph of the total electromagnetic shielding effectiveness of the composite fabrics with electromagnetic shielding effectiveness prepared by Examples 1-5 and Comparative Examples 1-3 of the present invention; Figure 4 The electromagnetic shielding effectiveness bar graph of the composite fabrics with electromagnetic shielding effectiveness prepared by Examples 1-5 and Comparative Examples 1-3 of the present invention; In the figure: 1. Aluminum rolled material, 2. Polyurethane hot melt adhesive, 3. Polyester film, 4. Electromagnetic shielding fabric. DETAILED DESCRIPTION

[0023] 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.

[0024] Embodiment 1: This embodiment discloses a method for preparing a composite fabric with electromagnetic shielding performance, comprising the following steps: Step (1), preparing an electromagnetic shielding coating; S11. Mix 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin, potassium thioacetate and N,N-dimethylformamide, and react at 55°C for 14 hours. After the reaction is completed, a crude reaction product is obtained, and dichloromethane with a volume of 50% of the crude reaction product is added for extraction. The lower layer of liquid is taken, and anhydrous magnesium sulfate with a mass of 10% of the lower layer of liquid is added for drying for 10 minutes, filtered, and the liquid component is taken, and rotary evaporated at 35°C for 4 hours to obtain an intermediate product. Wherein, the mass ratio of 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin, potassium thioacetate, and N,N-dimethylformamide is 5:6:35; The intermediate product, 30 wt% sodium methoxide methanol solution and tetrahydrofuran were mixed, and reacted for 6 hours at room temperature in a nitrogen atmosphere. After the reaction was completed, 0.1 mol / L hydrochloric acid aqueous solution was added to neutralize to a pH value of 6 to obtain a crude reaction product, and dichloromethane and water were added in a volume 3 times that of the crude reaction product and washed 4 times in sequence. The organic phase was taken, and anhydrous magnesium sulfate with a mass of 10% of the organic phase was added to dry for 10 minutes, filtered, and the liquid component was taken and rotary evaporated at 35° C. for 4 hours to obtain a modified thiophene monomer; The mass ratio of the intermediate product, 30 wt% sodium methoxide methanol solution, and tetrahydrofuran is 2:8:160; S12, mixing graphene oxide with 1 mol / L sulfuric acid aqueous solution, ultrasonically dispersing for 6 hours, adding modified thiophene monomer, ultrasonically dispersing for 4 hours, stirring at 0°C for 30 minutes, adding ammonium persulfate, reacting at 0°C for 20 hours, after the reaction, obtaining a crude reaction product, filtering, taking a precipitate, adding ethanol and water in an amount 3 times the mass of the precipitate in turn, washing for 4 times, and drying at 80°C for 20 hours to obtain a graphene oxide / modified polythiophene composite material; Wherein, the mass ratio of graphene oxide, 1 mol / L sulfuric acid aqueous solution, modified thiophene monomer, and ammonium persulfate is 0.1:160:0.45:1; The graphene oxide / modified polythiophene composite material was mixed with water, ultrasonically dispersed for 4 hours, nickel nitrate and iron nitrate were added, stirred for 50 minutes, 25wt% ammonia water was added to adjust the pH value to 11, reacted at 200°C for 10 hours, and after the reaction was completed, cooled to room temperature to obtain a crude reaction product, filtered, and the precipitate was taken, washed four times with water 3 times the mass of the precipitate, and dried at 80°C for 20 hours to obtain an electromagnetic shielding additive; Wherein, the mass ratio of graphene oxide / modified polythiophene composite material, water, nickel nitrate, and iron nitrate is 0.2:200:0.5:1.2; S13, mixing the electromagnetic shielding additive with the waterborne polyurethane acrylate, adding 2,2-dimethoxy-2-phenylacetophenone, stirring at 700 rpm for 30 minutes under light-proof conditions, and obtaining an electromagnetic shielding coating after the stirring is completed; Among them, the mass ratio of electromagnetic shielding additive, waterborne polyurethane acrylate, and 2,2-dimethoxy-2-phenylacetophenone is 2:100:0.7; The waterborne polyurethane acrylate is prepared by the following steps: Mix isophorone diisocyanate (IPDI) and polyethylene glycol, stir for 15 minutes under nitrogen atmosphere, add dibutyltin dilaurate, react at 70°C for 1 hour, add 2,2-dihydroxymethylpropionic acid (DMPA) after the reaction, continue to react at 90°C for 3 hours, add 2-hydroxyethyl methacrylate (HEMA) after the reaction, react again at 80°C for 4 hours, cool to room temperature after the reaction, add triethylamine, neutralize at room temperature for 1 hour, add water for emulsification, control the solid content at 50wt%, stir at 700rpm for 20 minutes to obtain waterborne polyurethane acrylate; the mass ratio of isophorone diisocyanate (IPDI), polyethylene glycol, dibutyltin dilaurate, 2,2-dihydroxymethylpropionic acid (DMPA), 2-hydroxyethyl methacrylate (HEMA), and triethylamine is 7:6.5:0.1:1.3:2:1; Step (2), mixing nylon 66 fabric, 3-mercaptopropyltriethoxysilane (MPTES) and a mixed solvent of ethanol and water, adding 0.5 mol / L acetic acid aqueous solution to adjust the pH value to 5, reacting at 80° C. for 2 h, and after the reaction is completed, taking out, adding ethanol to wash 4 times, and drying in a 120° C. forced air oven for 30 min to obtain a modified nylon 66 fabric; The mass ratio of nylon 66 fabric, 3-mercaptopropyltriethoxysilane (MPTES), and mixed solvent is 1:12:200; the volume ratio of ethanol to water in the mixed solvent is 9:1; The electromagnetic shielding coating was coated on both sides of the modified nylon 66 fabric, and reacted under 370nm ultraviolet light for 30 minutes. After the reaction, the fabric was dried in a 100°C blast oven for 30 minutes to obtain an electromagnetic shielding fabric. Among them, the single-side coating amount of electromagnetic shielding coating is 45g / m 2 ; Step (3), using electromagnetic shielding fabric as the inner layer, aluminum rolled material as the surface layer, and polyester film as the middle layer, coating both sides with polyurethane hot melt adhesive, placing electromagnetic shielding fabric and aluminum rolled material on both sides of the middle layer respectively, and heating at 135°C, 2.5N·cm -2 Hot pressing under pressure for 60 seconds to obtain a composite fabric with electromagnetic shielding performance; The glue amount of the inner layer electromagnetic shielding fabric and the middle layer polyester film, as well as the glue amount of the surface layer aluminum calendering material and the middle layer polyester film are both 25g / m 2 .

[0025] Embodiment 2: This embodiment discloses a method for preparing a composite fabric with electromagnetic shielding performance, comprising the following steps: Step (1), preparing an electromagnetic shielding coating; S11, 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin, potassium thioacetate and N,N-dimethylformamide were mixed and reacted at 45°C for 16 hours. After the reaction was completed, a crude reaction product was obtained, and dichloromethane (30% by volume of the crude reaction product) was added for extraction. The lower layer of liquid was taken, and anhydrous magnesium sulfate (5% by mass of the lower layer of liquid) was added for drying for 15 minutes, filtered, and the liquid component was taken and rotary evaporated at 25°C for 6 hours to obtain an intermediate product; Wherein, the mass ratio of 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin, potassium thioacetate, and N,N-dimethylformamide is 5:5:25; The intermediate product, 30 wt% sodium methoxide methanol solution and tetrahydrofuran were mixed, and reacted in a nitrogen atmosphere at room temperature for 4 hours. After the reaction was completed, 0.1 mol / L hydrochloric acid aqueous solution was added to neutralize to a pH value of 7 to obtain a crude reaction product, and dichloromethane and water were added in a volume of 5 times the volume of the crude reaction product and washed twice in sequence. The organic phase was taken, and anhydrous magnesium sulfate of 5% by mass of the organic phase was added to dry for 15 minutes, filtered, and the liquid component was taken and rotary evaporated at 25°C for 6 hours to obtain a modified thiophene monomer; The mass ratio of the intermediate product, 30 wt% sodium methoxide methanol solution, and tetrahydrofuran is 2:4:140; S12, mixing graphene oxide with 1 mol / L sulfuric acid aqueous solution, ultrasonically dispersing for 4 hours, adding modified thiophene monomer, ultrasonically dispersing for 2 hours, stirring at 5°C for 50 minutes, adding ammonium persulfate, reacting at 5°C for 24 hours, after the reaction, obtaining a crude reaction product, filtering, taking a precipitate, adding ethanol and water 5 times the mass of the precipitate in turn, washing twice, and drying at 60°C for 24 hours to obtain a graphene oxide / modified polythiophene composite material; Wherein, the mass ratio of graphene oxide, 1 mol / L sulfuric acid aqueous solution, modified thiophene monomer, and ammonium persulfate is 0.1:120:0.25:0.8; The graphene oxide / modified polythiophene composite material was mixed with water, ultrasonically dispersed for 2 hours, nickel nitrate and ferric nitrate were added, stirred for 30 minutes, 25wt% ammonia water was added to adjust the pH value to 10, reacted at 180°C for 12 hours, and after the reaction was completed, cooled to room temperature to obtain a crude reaction product, filtered, and the precipitate was taken, washed twice with water 5 times the mass of the precipitate, and dried at 60°C for 24 hours to obtain an electromagnetic shielding additive; Wherein, the mass ratio of graphene oxide / modified polythiophene composite material, water, nickel nitrate, and iron nitrate is 0.2:180:0.3:0.8; S13, mixing the electromagnetic shielding additive with the waterborne polyurethane acrylate, adding 2,2-dimethoxy-2-phenylacetophenone, stirring at 600 rpm for 50 minutes under light-proof conditions, and obtaining an electromagnetic shielding coating after the stirring is completed; Wherein, the mass ratio of electromagnetic shielding additive, waterborne polyurethane acrylate and 2,2-dimethoxy-2-phenylacetophenone is 0.5:100:0.5; the preparation method of waterborne polyurethane acrylate is the same as that in Example 1; Step (2), mixing nylon 66 fabric, 3-mercaptopropyltriethoxysilane (MPTES) and a mixed solvent of ethanol and water, adding 0.5 mol / L acetic acid aqueous solution to adjust the pH value to 4, reacting at 60° C. for 3 h, taking out after the reaction, adding ethanol to wash twice, and drying in a 100° C. forced air oven for 50 min to obtain a modified nylon 66 fabric; The mass ratio of nylon 66 fabric, 3-mercaptopropyltriethoxysilane (MPTES), and mixed solvent is 1:8:160; the volume ratio of ethanol to water in the mixed solvent is 9:1; The electromagnetic shielding coating was coated on both sides of the modified nylon 66 fabric, and reacted under 350nm ultraviolet light for 50 minutes. After the reaction, the fabric was dried in a blast oven at 80°C for 50 minutes to obtain the electromagnetic shielding fabric. Among them, the single-side coating amount of electromagnetic shielding coating is 25g / m 2 ; Step (3), using electromagnetic shielding fabric as the inner layer, aluminum rolled material as the surface layer, and polyester film as the middle layer, coating both sides with polyurethane hot melt adhesive, placing electromagnetic shielding fabric and aluminum rolled material on both sides of the middle layer respectively, and heating at 125°C, 2N·cm -2 Hot pressing under pressure for 80 seconds to obtain a composite fabric with electromagnetic shielding performance; The glue amount of the inner layer electromagnetic shielding fabric and the middle layer polyester film, as well as the glue amount of the surface aluminum calendering material and the middle layer polyester film are both 15g / m 2 .

[0026] Embodiment 3: This embodiment discloses a method for preparing a composite fabric with electromagnetic shielding performance, comprising the following steps: Step (1), preparing an electromagnetic shielding coating; S11. Mix 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin, potassium thioacetate and N,N-dimethylformamide, and react at 52°C for 14.5 hours. After the reaction is completed, a crude reaction product is obtained, and dichloromethane (45% by volume of the crude reaction product) is added for extraction. The lower layer of liquid is taken, and anhydrous magnesium sulfate (8% by mass of the lower layer of liquid) is added for drying for 11 minutes, filtered, and the liquid component is taken, and rotary evaporated at 32°C for 4.5 hours to obtain an intermediate product. Wherein, the mass ratio of 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin, potassium thioacetate, and N,N-dimethylformamide is 5:6:32; The intermediate product, 30 wt% sodium methoxide methanol solution and tetrahydrofuran were mixed, and reacted at room temperature in a nitrogen atmosphere for 5.5 h. After the reaction was completed, 0.1 mol / L hydrochloric acid aqueous solution was added to neutralize to a pH value of 6 to obtain a crude reaction product, and dichloromethane and water were added in a volume 3 times that of the crude reaction product to wash 4 times in sequence. The organic phase was taken, and anhydrous magnesium sulfate with a mass content of 8% of the organic phase was added to dry for 11 min, filtered, and the liquid component was taken and rotary evaporated at 32° C. for 4.5 h to obtain a modified thiophene monomer; The mass ratio of the intermediate product, 30 wt% sodium methoxide methanol solution, and tetrahydrofuran is 2:7:155; S12, mixing graphene oxide with 1 mol / L sulfuric acid aqueous solution, ultrasonically dispersing for 5.5 h, adding modified thiophene monomer, ultrasonically dispersing for 3.5 h, stirring at 1 ° C for 35 min, adding ammonium persulfate, reacting at 1 ° C for 21 h, after the reaction, obtaining a crude reaction product, filtering, taking the precipitate, adding ethanol and water 3 times the mass of the precipitate in turn, washing 4 times, and drying at 75 ° C for 21 h to obtain a graphene oxide / modified polythiophene composite material; Wherein, the mass ratio of graphene oxide, 1 mol / L sulfuric acid aqueous solution, modified thiophene monomer, and ammonium persulfate is 0.1:150:0.4:0.95; The graphene oxide / modified polythiophene composite material was mixed with water, ultrasonically dispersed for 3.5 hours, nickel nitrate and iron nitrate were added, stirred for 45 minutes, 25wt% ammonia water was added to adjust the pH value to 11, reacted at 195°C for 10.5 hours, and after the reaction was completed, cooled to room temperature to obtain a crude reaction product, filtered, and the precipitate was taken, washed four times with water 3 times the mass of the precipitate, and dried at 75°C for 21 hours to obtain an electromagnetic shielding additive; Wherein, the mass ratio of graphene oxide / modified polythiophene composite material, water, nickel nitrate, and iron nitrate is 0.2:195:0.45:1.1; S13, mixing the electromagnetic shielding additive with the waterborne polyurethane acrylate, adding 2,2-dimethoxy-2-phenylacetophenone, stirring at a speed of 675 rpm for 35 minutes under light-proof conditions, and obtaining an electromagnetic shielding coating after the stirring is completed; Wherein, the mass ratio of the electromagnetic shielding additive, the waterborne polyurethane acrylate, and 2,2-dimethoxy-2-phenylacetophenone is 1.6:100:0.65; the preparation method of the waterborne polyurethane acrylate is the same as that in Example 1; Step (2), mixing nylon 66 fabric, 3-mercaptopropyltriethoxysilane (MPTES) and a mixed solvent of ethanol and water, adding 0.5 mol / L acetic acid aqueous solution to adjust the pH value to 5, reacting at 75° C. for 2 h, and after the reaction is completed, taking out, adding ethanol to wash 4 times, and drying in a 115° C. forced air oven for 35 min to obtain a modified nylon 66 fabric; The mass ratio of nylon 66 fabric, 3-mercaptopropyltriethoxysilane (MPTES), and mixed solvent is 1:11:190; the volume ratio of ethanol to water in the mixed solvent is 9:1; The electromagnetic shielding coating was coated on both sides of the modified nylon 66 fabric, and reacted under 365nm ultraviolet light for 35 minutes. After the reaction, the fabric was dried in a 95°C forced air oven for 35 minutes to obtain an electromagnetic shielding fabric. Among them, the single-side coating amount of electromagnetic shielding coating is 40g / m 2 ; Step (3), using electromagnetic shielding fabric as the inner layer, aluminum rolled material as the surface layer, and polyester film as the middle layer, coating both sides with polyurethane hot melt adhesive, placing electromagnetic shielding fabric and aluminum rolled material on both sides of the middle layer respectively, and heating at 132°C, 2.3N·cm -2 Hot pressing for 65 seconds under pressure to obtain a composite fabric with electromagnetic shielding performance; The glue amount of the inner layer electromagnetic shielding fabric and the middle layer polyester film, as well as the glue amount of the surface layer aluminum calendering material and the middle layer polyester film are both 22g / m 2 .

[0027] Embodiment 4: This embodiment discloses a method for preparing a composite fabric with electromagnetic shielding performance, comprising the following steps: Step (1), preparing an electromagnetic shielding coating; S11. Mix 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin, potassium thioacetate and N,N-dimethylformamide, and react at 50°C for 15 hours. After the reaction is completed, a crude reaction product is obtained, and dichloromethane (40% by volume of the crude reaction product) is added for extraction. The lower layer of liquid is taken, and anhydrous magnesium sulfate (7% by mass of the lower layer of liquid) is added for drying for 12 minutes, filtered, and the liquid component is taken, and rotary evaporated at 30°C for 5 hours to obtain an intermediate product. Wherein, the mass ratio of 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin, potassium thioacetate, and N,N-dimethylformamide is 5:5.5:30; The intermediate product, 30 wt% sodium methoxide methanol solution and tetrahydrofuran were mixed, and reacted in a nitrogen atmosphere at room temperature for 5 h. After the reaction was completed, 0.1 mol / L hydrochloric acid aqueous solution was added to neutralize to a pH value of 6 to obtain a crude reaction product, and dichloromethane and water were added in a volume 4 times that of the crude reaction product and washed three times in sequence. The organic phase was taken, anhydrous magnesium sulfate (7% by mass of the organic phase) was added and dried for 12 min, filtered, and the liquid component was taken and rotary evaporated at 30° C. for 5 h to obtain a modified thiophene monomer; The mass ratio of the intermediate product, 30 wt% sodium methoxide methanol solution, and tetrahydrofuran is 2:6:150; S12, mixing graphene oxide with 1 mol / L sulfuric acid aqueous solution, ultrasonically dispersing for 5 hours, adding modified thiophene monomer, ultrasonically dispersing for 3 hours, stirring at 2°C for 40 minutes, adding ammonium persulfate, reacting at 2°C for 22 hours, after the reaction, obtaining a crude reaction product, filtering, taking a precipitate, adding ethanol and water 4 times the mass of the precipitate in turn, washing for 3 times, and drying at 70°C for 22 hours to obtain a graphene oxide / modified polythiophene composite material; Wherein, the mass ratio of graphene oxide, 1 mol / L sulfuric acid aqueous solution, modified thiophene monomer, and ammonium persulfate is 0.1:140:0.35:0.9; The graphene oxide / modified polythiophene composite material was mixed with water, ultrasonically dispersed for 3 hours, nickel nitrate and iron nitrate were added, stirred for 40 minutes, 25wt% ammonia water was added to adjust the pH value to 11, reacted at 190°C for 11 hours, and after the reaction was completed, cooled to room temperature to obtain a crude reaction product, filtered, and the precipitate was taken, washed three times with water 4 times the mass of the precipitate, and dried at 70°C for 22 hours to obtain an electromagnetic shielding additive; Wherein, the mass ratio of graphene oxide / modified polythiophene composite material, water, nickel nitrate and iron nitrate is 0.2:190:0.4:1; S13, mixing the electromagnetic shielding additive with the waterborne polyurethane acrylate, adding 2,2-dimethoxy-2-phenylacetophenone, stirring at 650 rpm for 40 minutes under light-proof conditions, and obtaining an electromagnetic shielding coating after the stirring is completed; Wherein, the mass ratio of electromagnetic shielding additive, waterborne polyurethane acrylate and 2,2-dimethoxy-2-phenylacetophenone is 1.2:100:0.6; the preparation method of waterborne polyurethane acrylate is the same as that in Example 1; Step (2), mixing nylon 66 fabric, 3-mercaptopropyltriethoxysilane (MPTES) and a mixed solvent of ethanol and water, adding 0.5 mol / L acetic acid aqueous solution to adjust the pH value to 5, reacting at 70° C. for 2.5 h, and after the reaction is completed, taking out, adding ethanol to wash 3 times, and drying in a 110° C. forced air oven for 40 min to obtain a modified nylon 66 fabric; The mass ratio of nylon 66 fabric, 3-mercaptopropyltriethoxysilane (MPTES), and mixed solvent is 1:10:180; the volume ratio of ethanol to water in the mixed solvent is 9:1; The electromagnetic shielding coating was coated on both sides of the modified nylon 66 fabric, and reacted under 360nm ultraviolet light for 40 minutes. After the reaction, the fabric was dried in a 90°C blast oven for 40 minutes to obtain an electromagnetic shielding fabric. Among them, the single-side coating amount of electromagnetic shielding coating is 35g / m 2 ; Step (3), using electromagnetic shielding fabric as the inner layer, aluminum rolled material as the surface layer, and polyester film as the middle layer, coating both sides with polyurethane hot melt adhesive, placing electromagnetic shielding fabric and aluminum rolled material on both sides of the middle layer respectively, and heating at 130°C and 2.2N·cm -2 Hot pressing under pressure for 70 seconds to obtain a composite fabric with electromagnetic shielding performance; The glue amount of the inner layer electromagnetic shielding fabric and the middle layer polyester film, as well as the glue amount of the surface layer aluminum calendering material and the middle layer polyester film are both 20g / m 2 .

[0028] Embodiment 5: This embodiment discloses a method for preparing a composite fabric with electromagnetic shielding performance, comprising the following steps: Step (1), preparing an electromagnetic shielding coating; S11. Mix 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin, potassium thioacetate and N,N-dimethylformamide, and react at 48°C for 15.5 hours. After the reaction is completed, a crude reaction product is obtained, and dichloromethane (35% by volume of the crude reaction product) is added for extraction. The lower layer of liquid is taken, and anhydrous magnesium sulfate (6% by mass of the lower layer of liquid) is added for drying for 13 minutes, filtered, and the liquid component is taken, and rotary evaporated at 28°C for 5.5 hours to obtain an intermediate product. Wherein, the mass ratio of 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin, potassium thioacetate, and N,N-dimethylformamide is 5:5:28; The intermediate product, 30 wt% sodium methoxide methanol solution and tetrahydrofuran were mixed, and reacted in a nitrogen atmosphere at room temperature for 4.5 hours. After the reaction was completed, 0.1 mol / L hydrochloric acid aqueous solution was added to neutralize to a pH value of 7 to obtain a crude reaction product, and dichloromethane and water were added in a volume 5 times that of the crude reaction product and washed twice in sequence. The organic phase was taken, and anhydrous magnesium sulfate of 6% by mass of the organic phase was added to dry for 13 minutes, filtered, and the liquid component was taken and rotary evaporated at 28°C for 5.5 hours to obtain a modified thiophene monomer; The mass ratio of the intermediate product, 30 wt% sodium methoxide methanol solution, and tetrahydrofuran is 2:5:145; S12, mixing graphene oxide with 1 mol / L sulfuric acid aqueous solution, ultrasonically dispersing for 4.5 hours, adding modified thiophene monomer, ultrasonically dispersing for 2.5 hours, stirring at 3°C ​​for 45 minutes, adding ammonium persulfate, reacting at 3°C ​​for 23 hours, after the reaction, obtaining a crude reaction product, filtering, taking a precipitate, adding ethanol and water 5 times the mass of the precipitate in turn, washing twice, and drying at 65°C for 23 hours to obtain a graphene oxide / modified polythiophene composite material; Wherein, the mass ratio of graphene oxide, 1 mol / L sulfuric acid aqueous solution, modified thiophene monomer, and ammonium persulfate is 0.1:130:0.3:0.85; The graphene oxide / modified polythiophene composite material was mixed with water, ultrasonically dispersed for 2.5 hours, nickel nitrate and iron nitrate were added, stirred for 35 minutes, 25wt% ammonia water was added to adjust the pH value to 10, reacted at 185°C for 11.5 hours, and after the reaction was completed, cooled to room temperature to obtain a crude reaction product, filtered, and the precipitate was taken, washed twice with water 5 times the mass of the precipitate, and dried at 65°C for 23 hours to obtain an electromagnetic shielding additive; Wherein, the mass ratio of graphene oxide / modified polythiophene composite material, water, nickel nitrate, and iron nitrate is 0.2:185:0.35:0.9; S13, mixing the electromagnetic shielding additive with the waterborne polyurethane acrylate, adding 2,2-dimethoxy-2-phenylacetophenone, stirring at a speed of 625 rpm for 45 minutes under light-proof conditions, and obtaining an electromagnetic shielding coating after the stirring is completed; Wherein, the mass ratio of the electromagnetic shielding additive, the waterborne polyurethane acrylate, and 2,2-dimethoxy-2-phenylacetophenone is 0.8:100:0.55; the preparation method of the waterborne polyurethane acrylate is the same as that in Example 1; Step (2), mixing nylon 66 fabric, 3-mercaptopropyltriethoxysilane (MPTES) and a mixed solvent of ethanol and water, adding 0.5 mol / L acetic acid aqueous solution to adjust the pH value to 4, reacting at 65° C. for 3 h, and after the reaction is completed, taking out, adding ethanol to wash twice, and drying in a 105° C. forced air oven for 45 min to obtain a modified nylon 66 fabric; The mass ratio of nylon 66 fabric, 3-mercaptopropyltriethoxysilane (MPTES), and mixed solvent is 1:9:170; the volume ratio of ethanol and water in the mixed solvent is 9:1; The electromagnetic shielding coating was coated on both sides of the modified nylon 66 fabric, and reacted under 355nm ultraviolet light for 45 minutes. After the reaction, the fabric was dried in a blast oven at 85°C for 45 minutes to obtain an electromagnetic shielding fabric. Among them, the single-side coating amount of electromagnetic shielding coating is 30g / m 2 ; Step (3), using electromagnetic shielding fabric as the inner layer, aluminum rolled material as the surface layer, and polyester film as the middle layer, coating both sides with polyurethane hot melt adhesive, placing electromagnetic shielding fabric and aluminum rolled material on both sides of the middle layer respectively, and heating at 128°C, 2.1N·cm -2 Hot pressing under pressure for 75 seconds to obtain a composite fabric with electromagnetic shielding performance; The glue amount of the inner layer electromagnetic shielding fabric and the middle layer polyester film, as well as the glue amount of the surface aluminum calendering material and the middle layer polyester film are both 18g / m 2 .

[0029] Comparative Example 1: This comparative example discloses a method for preparing a composite fabric, comprising the following steps: Step (1), preparing a modified coating; The graphene oxide was mixed with water, ultrasonically dispersed for 2 hours, nickel nitrate and iron nitrate were added, stirred for 30 minutes, 25wt% ammonia water was added to adjust the pH value to 10, reacted at 180°C for 12 hours, and after the reaction, cooled to room temperature to obtain a crude reaction product, filtered, and the precipitate was taken, washed twice with water 5 times the mass of the precipitate, and dried at 60°C for 24 hours to obtain a composite additive; Among them, the mass ratio of graphene oxide, water, nickel nitrate and iron nitrate is 0.2:180:0.3:0.8; The composite additive is mixed with waterborne polyurethane acrylate, 2,2-dimethoxy-2-phenylacetophenone is added, and the mixture is stirred at 600 rpm for 50 minutes under light-proof conditions. After the stirring is completed, a modified coating is obtained; Wherein, the mass ratio of the composite additive, waterborne polyurethane acrylate, and 2,2-dimethoxy-2-phenylacetophenone is 0.5:100:0.5; the preparation method of waterborne polyurethane acrylate is the same as that in Example 1; Step (2), mixing nylon 66 fabric, 3-mercaptopropyltriethoxysilane (MPTES) and a mixed solvent of ethanol and water, adding 0.5 mol / L acetic acid aqueous solution to adjust the pH value to 4, reacting at 60° C. for 3 h, taking out after the reaction, adding ethanol to wash twice, and drying in a 100° C. forced air oven for 50 min to obtain a modified nylon 66 fabric; The mass ratio of nylon 66 fabric, 3-mercaptopropyltriethoxysilane (MPTES), and mixed solvent is 1:8:160; the volume ratio of ethanol to water in the mixed solvent is 9:1; The modified coating was coated on both sides of the modified nylon 66 fabric, and reacted under 350nm ultraviolet light for 50 minutes. After the reaction, it was dried in a blast oven at 80°C for 50 minutes to obtain the modified fabric; Among them, the single-side coating amount of the modified coating is 25g / m 2 ; Step (3), using the modified fabric as the inner layer, the aluminum rolled material as the surface layer, and the polyester film as the middle layer, coating both sides with polyurethane hot melt adhesive, placing the modified fabric and the aluminum rolled material on both sides of the middle layer respectively, and heating the polyester film at 125°C and 2N·cm -2 Hot pressing under pressure for 80 seconds to obtain a composite fabric; The glue amount of the inner modified fabric and the middle polyester film as well as the glue amount of the surface aluminum calendering material and the middle polyester film are both 15g / m 2 .

[0030] Comparative Example 2: This comparative example discloses a method for preparing a composite fabric, comprising the following steps: Step (1), preparing a modified coating; S11, 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin, potassium thioacetate and N,N-dimethylformamide were mixed and reacted at 45°C for 16 hours. After the reaction was completed, a crude reaction product was obtained, and dichloromethane (30% by volume of the crude reaction product) was added for extraction. The lower layer of liquid was taken, and anhydrous magnesium sulfate (5% by mass of the lower layer of liquid) was added for drying for 15 minutes, filtered, and the liquid component was taken and rotary evaporated at 25°C for 6 hours to obtain an intermediate product; Wherein, the mass ratio of 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin, potassium thioacetate, and N,N-dimethylformamide is 5:5:25; The intermediate product, 30 wt% sodium methoxide methanol solution and tetrahydrofuran were mixed, and reacted in a nitrogen atmosphere at room temperature for 4 hours. After the reaction was completed, 0.1 mol / L hydrochloric acid aqueous solution was added to neutralize to a pH value of 7 to obtain a crude reaction product, and dichloromethane and water were added in a volume of 5 times the volume of the crude reaction product and washed twice in sequence. The organic phase was taken, and anhydrous magnesium sulfate of 5% by mass of the organic phase was added to dry for 15 minutes, filtered, and the liquid component was taken and rotary evaporated at 25°C for 6 hours to obtain a modified thiophene monomer; The mass ratio of the intermediate product, 30 wt% sodium methoxide methanol solution, and tetrahydrofuran is 2:4:140; S12, mixing graphene oxide with 1 mol / L sulfuric acid aqueous solution, ultrasonically dispersing for 4 hours, adding modified thiophene monomer, ultrasonically dispersing for 2 hours, stirring at 5°C for 50 minutes, adding ammonium persulfate, reacting at 5°C for 24 hours, after the reaction, obtaining a crude reaction product, filtering, taking a precipitate, adding ethanol and water 5 times the mass of the precipitate in turn, washing twice, and drying at 60°C for 24 hours to obtain a graphene oxide / modified polythiophene composite material; Wherein, the mass ratio of graphene oxide, 1 mol / L sulfuric acid aqueous solution, modified thiophene monomer, and ammonium persulfate is 0.1:120:0.25:0.8; S13, mixing the graphene oxide / modified polythiophene composite material with waterborne polyurethane acrylate, adding 2,2-dimethoxy-2-phenylacetophenone, stirring at 600 rpm for 50 minutes under light-proof conditions, and obtaining a modified coating after the stirring is completed; Wherein, the mass ratio of graphene oxide / modified polythiophene composite material, waterborne polyurethane acrylate, and 2,2-dimethoxy-2-phenylacetophenone is 0.5:100:0.5; the preparation method of waterborne polyurethane acrylate is the same as that in Example 1; Step (2), mixing nylon 66 fabric, 3-mercaptopropyltriethoxysilane (MPTES) and a mixed solvent of ethanol and water, adding 0.5 mol / L acetic acid aqueous solution to adjust the pH value to 4, reacting at 60° C. for 3 h, taking out after the reaction, adding ethanol to wash twice, and drying in a 100° C. forced air oven for 50 min to obtain a modified nylon 66 fabric; The mass ratio of nylon 66 fabric, 3-mercaptopropyltriethoxysilane (MPTES), and mixed solvent is 1:8:160; the volume ratio of ethanol to water in the mixed solvent is 9:1; The modified coating was coated on both sides of the modified nylon 66 fabric, and reacted under 350nm ultraviolet light for 50 minutes. After the reaction, it was dried in a blast oven at 80°C for 50 minutes to obtain the modified fabric; Among them, the single-side coating amount of the modified coating is 25g / m 2 ; Step (3), using the modified fabric as the inner layer, the aluminum rolled material as the surface layer, and the polyester film as the middle layer, coating both sides with polyurethane hot melt adhesive, placing the modified fabric and the aluminum rolled material on both sides of the middle layer respectively, and heating the polyester film at 125°C and 2N·cm -2 Hot pressing under pressure for 80 seconds to obtain a composite fabric; The glue amount of the inner modified fabric and the middle polyester film as well as the glue amount of the surface aluminum calendering material and the middle polyester film are both 15g / m 2 .

[0031] Comparative Example 3: This comparative example discloses a method for preparing a composite fabric, comprising the following steps: Step (1), using nylon 66 fabric as the inner layer, aluminum rolled material as the surface layer, and polyester film as the middle layer, coating both sides with polyurethane hot melt adhesive, placing nylon 66 fabric and aluminum rolled material on both sides of the middle layer respectively, and heating at 125°C, 2N·cm -2 Hot pressing under pressure for 80 seconds to obtain a composite fabric; The glue amount of the inner layer nylon 66 fabric and the middle layer polyester film, as well as the glue amount of the surface layer aluminum calendering material and the middle layer polyester film are both 15g / m 2 .

[0032] In the above examples and comparative examples: 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin was from Wuxi Jiehua Pharmaceutical Technology Co., Ltd., CAS No.: 857419-46-6; potassium thioacetate was from Tianjin Xinbote Chemical Co., Ltd., CAS No.: 10387-40-3; N,N-dimethylformamide was from Tianjin Xinbote Chemical Co., Ltd., CAS No.: 68-12-2; dichloromethane was from Tianjin Xinbote Chemical Co., Ltd., CAS No.: 75-09-2; anhydrous magnesium sulfate was from Laizhou Guang Cheng Chemical Co., Ltd., CAS No.: 7487-88-9; Sodium methoxide methanol solution comes from, CAS No.: 124-41-4; Tetrahydrofuran comes from Jinzhou Boyi Chemical Technology Co., Ltd., CAS No.: 109-99-9; Graphene oxide comes from Angxing New Carbon Materials Changzhou Co., Ltd., oxygen content 50wt%, model: GO1211; Ammonium persulfate comes from Sinopharm Chemical Reagent Co., Ltd., CAS No.: 7727-54-0; Nickel nitrate comes from Sinopharm Chemical Reagent Co., Ltd., molecular formula: Ni(NO 3 ) 2 6H 2 O; ferric nitrate was from Sinopharm Chemical Reagent Co., Ltd., molecular formula: Fe(NO 3 ) 3 9H 2 O; isophorone diisocyanate (IPDI) was from Shanghai MacLean Biochemical Technology Co., Ltd., CAS No.: 4098-71-9; polyethylene glycol was from TCI (Shanghai) Chemical Industry Development Co., Ltd., Mw=300g / mol, model: H0543, CAS No.: 25322-68-3; dibutyltin dilaurate was from Shanghai Organic Pharmaceutical Chemistry Production Co., Ltd., CAS No.: 77-58-7; 2,2-dihydroxymethylpropionic acid (DMPA) was from TCI (Shanghai) Chemical Industry Development Co., Ltd. Co., Ltd., CAS No.: 4767-03-7; 2-hydroxyethyl methacrylate (HEMA) was from TCI (Shanghai) Chemical Industry Development Co., Ltd., CAS No.: 868-77-9; triethylamine was from Sinopharm Chemical Reagent Co., Ltd., CAS No.: 121-44-8; 2,2-dimethoxy-2-phenylacetophenone was from Shanghai Adamas Reagent Co., Ltd., CAS No.: 24650-42-8; nylon 66 fabric was from Hangzhou Xinsheng Printing and Dyeing Co., Ltd., weight 40g / m 2 , thickness 50μm; polyester film comes from Tianjin Deli Film Co., Ltd., product name: BOPET biaxially oriented polyester film, thickness 25μm; aluminum calendering material comes from Shanghai Xingnuo Industrial Co., Ltd., product name: 8079 aluminum foil, thickness 50μm; polyurethane hot melt adhesive comes from Walter Adhesive Materials Co., Ltd., model: HT-9260.

[0033] Test example: (1) Comprehensive performance test The mechanical properties of the inner layer fabrics in the composite fabrics prepared in Examples 1-5 and Comparative Examples 1-3 were tested, and the specific test results are shown in Table 1; the comprehensive performance tests of the composite fabrics prepared in Examples 1-5 and Comparative Examples 1-3 were performed, and the specific test results are shown in Table 2: Table 1 Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Comparative Example 3 Elongation at break (%) 55.8 52.6 55.4 54.1 52.9 49.7 50.2 33.6 Table 2 Total electromagnetic shielding effectiveness (dB) Absorption electromagnetic shielding effectiveness (dB) Example 1 64.6 57.3 Example 2 58.2 51.5 Example 3 63.1 55.4 Example 4 61.9 53.7 Example 5 59.7 52.9 Comparative Example 1 48.4 42.6 Comparative Example 2 43.3 28.1 Comparative Example 3 22.6 13.5 The testing of various indicators in Table 1 and Table 2 is based on the following standards: the elongation at break is measured by GB / T 3923.1-2013 "Tensile properties of textile fabrics Part 1: Determination of breaking strength and elongation at break (strip method)"; the total electromagnetic shielding effectiveness and absorbed electromagnetic shielding effectiveness are measured by SJ20524-1995 "Test method for shielding effectiveness of materials".

[0034] It can be seen from the test results in Table 2 that the composite fabric prepared by the present invention has low reflection and high absorption electromagnetic shielding effectiveness.

[0035] In Comparative Example 1, the thiophene monomer is not modified and grafted onto the surface of graphene oxide to form a conductive modified polythiophene, thereby reducing the electrical component in the additive, making it impossible to synergize with graphene oxide, reducing the dielectric loss effect of the additive, and thus reducing the electromagnetic shielding effect of the modified fabric. Therefore, the total electromagnetic shielding effectiveness and the absorption electromagnetic shielding effectiveness of Comparative Example 1 are smaller than those of the embodiment.

[0036] In Comparative Example 2, magnetic nickel ferrite is not hydrothermally generated on the surface of the graphene oxide / modified polythiophene composite material. The modified coating obtained by mixing it with water-based polyurethane acrylate lacks magnetic components, which reduces the interfacial polarization and multiple scattering effects of electromagnetic waves, thereby reducing the electromagnetic shielding effect of the modified fabric. Therefore, the total electromagnetic shielding effectiveness and absorption electromagnetic shielding effectiveness of Comparative Example 2 are smaller than those of the embodiment.

[0037] In Comparative Example 3, no electromagnetic shielding coating was prepared, and only nylon 66 fabric was used as the inner fabric. Due to the lack of the functional layer coating on the outside of the fabric, its mechanical properties were reduced, thereby affecting the elongation at break of the inner fabric. Therefore, the elongation at break of the inner fabric in Comparative Example 3 was smaller than that in the embodiment. At the same time, although the aluminum rolled material has conductive and shielding properties, its electromagnetic shielding effect is not sufficient and complete due to the lack of the synergistic effect of the electrical component graphene and modified polythiophene and the magnetic component nickel ferrite. Therefore, the total electromagnetic shielding effectiveness and absorption electromagnetic shielding effectiveness of Comparative Example 3 are smaller than those in the embodiment.

[0038] 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 composite fabric with electromagnetic shielding performance, characterized in that: The following steps are involved: Step (1), preparing an electromagnetic shielding coating; The graphene oxide is mixed with a sulfuric acid aqueous solution, a modified thiophene monomer is added, the mixture is stirred, ammonium persulfate is added, the mixture is reacted, and after the reaction is completed, post-processing is performed to obtain a graphene oxide / modified polythiophene composite material; The graphene oxide / modified polythiophene composite material is mixed with water, nickel nitrate and iron nitrate are added, stirred, reacted, and after the reaction is completed, post-processed to obtain an electromagnetic shielding additive; The electromagnetic shielding additive is mixed with waterborne polyurethane acrylate, 2,2-dimethoxy-2-phenylacetophenone is added, and the mixture is stirred. After the stirring is completed, an electromagnetic shielding coating is obtained. Step (2), coating the electromagnetic shielding coating on both sides of the modified nylon 66 fabric, reacting, and drying after the reaction is completed to obtain the electromagnetic shielding fabric; Step (3), compounding the electromagnetic shielding fabric, the polyester film, and the aluminum calendering material by means of polyurethane hot melt adhesive, and hot pressing to obtain a composite fabric with electromagnetic shielding performance.

2. The method for preparing a composite fabric with electromagnetic shielding performance according to claim 1, characterized in that: In the step (1), the mass ratio of graphene oxide, sulfuric acid aqueous solution, modified thiophene monomer and ammonium persulfate is 0.1:(120-160):(0.25-0.45):(0.8-1); the concentration of sulfuric acid aqueous solution is 1 mol / L; when preparing the graphene oxide / modified polythiophene composite material, the reaction conditions are: reacting at a temperature of 0-5°C for 20-24h.

3. The method for preparing a composite fabric with electromagnetic shielding performance according to claim 2, characterized in that: The modified thiophene monomer in step (1) is prepared by the following steps: Mix 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin, potassium thioacetate and N,N-dimethylformamide, react, extract, dry and filter after the reaction to obtain an intermediate product; mix the intermediate product, 30 wt% sodium methoxide methanol solution and tetrahydrofuran, react, neutralize the pH after the reaction, wash, dry and filter to obtain a modified thiophene monomer; Among them, the mass ratio of 2-(chloromethyl)-2,3-dihydro-thieno[3,4-b]-1,4-dioxin, potassium thioacetate, and N,N-dimethylformamide is 5:(5-6):(25-35); when preparing the intermediate product, the reaction conditions are: reacting at a temperature of 45-55°C for 14-16h; the mass ratio of the intermediate product, 30wt% sodium methoxide methanol solution, and tetrahydrofuran is 2:(4-8):(140-160); when preparing the modified thiophene monomer, the reaction conditions are: reacting at room temperature in a nitrogen atmosphere for 4-6h.

4. The method for preparing a composite fabric with electromagnetic shielding performance according to claim 1, characterized in that: In the step (1), the mass ratio of the graphene oxide / modified polythiophene composite material, water, nickel nitrate and ferric nitrate is 0.2:(180-200):(0.3-0.5):(0.8-1.2); when preparing the electromagnetic shielding additive, the reaction conditions are: reacting at pH=10-11 and 180-200°C for 10-12h.

5. The method for preparing a composite fabric with electromagnetic shielding performance according to claim 1, characterized in that: In the step (1), the mass ratio of the electromagnetic shielding additive, the waterborne polyurethane acrylate, and the 2,2-dimethoxy-2-phenylacetophenone is (0.5-2):100:(0.5-0.7); when preparing the electromagnetic shielding coating, the stirring conditions are: stirring at a speed of 600-700 rpm for 30-50 minutes under light-proof conditions.

6. The method for preparing a composite fabric with electromagnetic shielding performance according to claim 5, characterized in that: The waterborne polyurethane acrylate in step (1) is prepared by the following steps: Mix isophorone diisocyanate and polyethylene glycol, stir, add dibutyltin dilaurate, react, add 2,2-dihydroxymethylpropionic acid after the reaction is completed, continue to react, add 2-hydroxyethyl methacrylate after the reaction is completed, react again, add triethylamine after the reaction is completed, neutralize, emulsify, stir, and obtain waterborne polyurethane acrylate; Among them, the mass ratio of isophorone diisocyanate, polyethylene glycol, dibutyltin dilaurate, 2,2-dihydroxymethylpropionic acid, 2-hydroxyethyl methacrylate and triethylamine is 7:(5.5-6.5):(0.05-0.1):(1.1-1.3):(1.8-2):(0.8-1); the reaction conditions are: react at 60-70°C for 1-2h; the continued reaction conditions are: continue to react at 80-90°C for 3-5h; the second reaction conditions are: react again at 70-80°C for 4-6h; the neutralization reaction conditions are: neutralize at room temperature for 0.5-1h; the solid content after emulsification is controlled at 40-50wt%.

7. The method for preparing a composite fabric with electromagnetic shielding effectiveness according to claim 1, characterized in that: In step (2): the single-side coating amount of the electromagnetic shielding coating is 25-45 g / m 2 ; The reaction conditions are: reacting under 350-370nm ultraviolet light for 30-50min; The modified nylon 66 fabric comprises the following steps: mixing nylon 66 fabric, 3-mercaptopropyltriethoxysilane and a mixed solvent of ethanol and water, adjusting the pH, reacting, and after the reaction is completed, washing and drying to obtain the modified nylon 66 fabric; the mass ratio of nylon 66 fabric, 3-mercaptopropyltriethoxysilane and the mixed solvent is 1:(8-12):(160-200), and the volume ratio of ethanol and water in the mixed solvent is 9:1; the reaction conditions are: reacting at pH=4-5 and a temperature of 60-80°C for 2-3h.

8. The method for preparing a composite fabric with electromagnetic shielding performance according to claim 1, characterized in that: In the step (3), the glue amount of the inner layer electromagnetic shielding fabric and the middle layer polyester film, and the glue amount of the surface layer aluminum calendering material and the middle layer polyester film are both 15-25g / m 2 ; Hot pressing conditions: 125-135℃ temperature, 2-2.5N·cm -2 Heat press under pressure for 60-80s.

9. A composite fabric with electromagnetic shielding performance, characterized in that: The composite fabric having electromagnetic shielding performance is prepared by the preparation method of any one of claims 1 to 8.

10. Use of the composite fabric with electromagnetic shielding performance as claimed in claim 9 in a tent.

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