High-shielding medical fabric based on surface amphiphobic treatment technology and preparation method

Abstract

The invention discloses a high-shielding medical fabric based on a surface amphiphobic treatment technology and a preparation method, and relates to the technical field of medical fabrics, the high-shielding medical fabric comprises a base material layer, a shielding function layer and an amphiphobic treatment layer which are sequentially arranged from bottom to top, the base material layer is of a warp-knitted structure formed by blending polyvinyl chloride fibers and polyester fibers according to the proportion of 3: 7-5: 5, and the shielding function layer is of a warp-knitted structure formed by blending the polyvinyl chloride fibers and the polyester fibers according to the proportion of 3: 7-5: 5. The polyvinyl chloride fiber is treated by a sulfonation modification solution. Quaternary ammonium salt groups are introduced through sulfonation modification, a positive charge surface is formed, the bacterial adsorption capacity is enhanced, nano-silver in the shielding functional layer plays a contact sterilization role through ion release, active oxygen free radicals can be generated due to the photocatalytic activity of the composite titanium dioxide nanorods, and the physical-chemical-photocatalytic triple antibacterial synergistic effect is achieved; and then the proportion of the nano-silver crystal face is precisely regulated and controlled through an ultraviolet reduction process, the high-catalytic-activity crystal face is exposed, and by combining the heterojunction structure design, the light response efficiency is remarkably improved, and the antibacterial lasting effect is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of medical fabrics, in particular to a high-shielding medical fabric based on surface amphiphobic treatment technology and a preparation method thereof. Background Art

[0002] The background technology of medical fabrics involves the intersection of materials science, textile engineering, medicine and biotechnology. Its development stems from the continuous improvement of the demand for medical protection, patient care and infection control. Medical protective fabrics are crucial in the medical environment and can be used for surgical gowns, isolation suits, etc. They must have the function of blocking blood, body fluids and microorganisms to protect the bodies of medical staff.

[0003] The defects of existing high-shielding medical fabrics are: 1. Patent document US06217505B1 discloses a medical fabric product. However, the medical fabric described in the above document has a single antibacterial mechanism and lacks a synergistic effect, which in turn leads to technical problems such as poor antibacterial rubber. 2. Patent document US4919998A discloses woven medical fabrics. However, the medical fabrics in the above document have insufficient electromagnetic shielding frequency band coverage, resulting in poor shielding effect. 3. Patent document US20150299359A1 discloses a medical fabric with an integral shape memory polymer. However, the medical fabric in the above document has poor amphiphobic surface stability and technical problems such as performance degradation after repeated use. 4. Patent document CN104248119A discloses a breathable medical fabric. However, the medical fabric in the above document has insufficient material interface bonding strength, which leads to technical problems such as easy peeling or aging. Summary of the Invention

[0004] The purpose of the present invention is to provide a high-shielding medical fabric based on surface amphiphobic treatment technology and a preparation method thereof, so as to solve the technical problems raised in the above-mentioned background technology.

[0005] To achieve the above objectives, the present invention provides the following technical solutions: a high-shielding medical fabric based on surface amphiphobic treatment technology, comprising a base material layer, a shielding functional layer, and an amphiphobic treatment layer arranged in sequence from bottom to top, wherein the base material layer comprises a warp knitted structure formed by blending polyvinyl chloride fiber and polyester fiber in a ratio of 3:7-5:5, the polyvinyl chloride fiber being treated with a sulfonated modification solution, with a surface grafting rate of 8% to 15%, the polyester fiber being doped with 0.1-0.5wt% of a carbon nanotube / graphene oxide hybrid material, and the surface resistivity of the hybrid material is 10^3Ω / sq when the doping amount is 0.3wt%, and 10^2Ω / sq when the doping amount is 0.5wt%; The shielding function layer is a nanosilver / polyurethane composite film loaded on the surface of the substrate layer by an electrospinning process, with a thickness of 50-200 μm, wherein the nanosilver accounts for 0.5% to 3% by weight, has a particle size of 20-50 nm, and is composited with titanium dioxide nanorods with an aspect ratio of 15:1-20:1, and the mass ratio of titanium dioxide nanorods to nanosilver is 1:3-1:5; The double-repellent treatment layer is formed by vapor deposition of a modified solution of perfluoroalkyltriethoxysilane and hexadecyltrimethoxysilane in a ratio of 1:2-1:4, and hydrophobic silica aerogel particles with a mass ratio of 10% to 20% of fluorosilane are added, with a water contact angle of ≥150° and an oil contact angle of ≥140°.

[0006] Preferably, 2-5 wt% of 2,3-epoxypropyltrimethylammonium chloride is added to the sulfonated modified solution to simultaneously graft quaternary ammonium salt groups onto the fiber surface, and the Zeta potential of the fiber surface is +15 mV to +30 mV.

[0007] Preferably, the nanosilver in the shielding functional layer is gradiently dispersed by polyvinyl pyrrolidone, and the titanium dioxide nanorods are distributed in a gradient along the thickness direction of the film.

[0008] Preferably, the hydrophobic silica aerogel particles in the amphiphobic treatment layer have a particle size of 50-100 nm, and are surface-modified with perfluorodecyltriethoxysilane, which is cross-linked with fluorosilane via siloxane bonds.

[0009] Preferably, the polyester fiber surface of the substrate layer is provided with a micron-scale groove structure with a groove depth of 0.5-2 μm, a width of 1-3 μm, and a depth-to-width ratio of 1:1.5-1:2, and the carbon nanotubes or graphene oxide are directionally arranged along the grooves.

[0010] Preferably, a transition layer is provided between the shielding functional layer and the amphiphobic treatment layer. The transition layer adopts a polydopamine / chitosan composite film with a thickness of 5-10 μm and contains 0.1-0.5 wt% of nanocellulose crystals. The nanocellulose crystals are a composite of cerium dioxide and zinc oxide with a particle size of ≤100 nm.

[0011] Preferably, the preparation steps of the high-shielding medical fabric based on the surface amphiphobic treatment technology are as follows: S1. Substrate pretreatment: immerse the polyvinyl chloride / polyester blended fabric in an ethanol solution containing 5-8 wt% sodium hydroxide and ultrasonically treat at 50°C for 30-60 min; S2. Shielding layer construction: A polyurethane spinning solution containing 0.1-0.5 M silver nitrate and titanium dioxide nanorods was prepared, and electrospinning was performed using multi-stage voltage control with an initial voltage of 12 kV and a linear increase to 22 kV within 10 min; S3, UV reduction: irradiate with a 365nm UV light source for 30-60min, and introduce nitrogen protection with an oxygen concentration of ≤50ppm, and adjust the nanosilver (111) crystal plane index and the nanosilver (200) crystal plane index to a ratio of 2.5-3.8:1; S4, plasma activation: Argon plasma treatment, the power is 200 ~ 400W, the time is 3 ~ 8 minutes, so that the surface oxygen content increases by 5% ~ 8%; S5. Amphiphobic treatment: Immerse the activated substrate in an isopropyl alcohol solution containing 1-3wt% fluorosilane, 0.01-0.1wt% erucamide and hydrophobic silica aerogel, and use a gradient temperature increase program. The temperature increase process is 5℃ / min to 80℃ and kept for 10 minutes, then increased to 150℃ at 3℃ / min, and cured for 30-60 minutes.

[0012] Preferably, in step S2, the titanium dioxide nanorods are prepared by a hydrothermal method, the reaction system comprises 0.1-0.3 M tetrabutyl titanate and 1-3 M hydrochloric acid, the reaction temperature is 160-180° C., and the reaction time is 12 to 24 h.

[0013] Preferably, the surface oxidation degree of the nanosilver after ultraviolet reduction in step S3 is ≤5%, and a Z-shaped heterostructure is formed between the nanosilver and the titanium dioxide nanorods.

[0014] Preferably, 0.05-0.2 wt % of an epoxy silane coupling agent is further added to the isopropyl alcohol solution in step S5 to enhance the interfacial bonding force between the hydrophobic silica aerogel particles and the fluorosilane.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention introduces quaternary ammonium groups through sulfonation modification to form a positively charged surface, enhancing bacterial adsorption capacity. The nanosilver in the shielding functional layer exerts a contact bactericidal effect through ion release. The photocatalytic activity of the composite titanium dioxide nanorods can generate reactive oxygen free radicals, achieving a physical-chemical-photocatalytic triple antibacterial synergistic effect. The ultraviolet reduction process then precisely controls the ratio of nanosilver crystal faces to expose highly catalytically active crystal faces. Combined with the heterojunction structure design, the photoresponse efficiency and antibacterial durability are significantly improved. 2. In this invention, carbon nanotubes / graphene oxide in the substrate layer are arranged along the fiber grooves to form micron-scale conductive pathways. Gradiently dispersed silver nanoparticles in the shielding layer form a nanoscale conductive network. These two elements work together to achieve a dual shielding mechanism of electromagnetic wave reflection and absorption. Titanium dioxide nanorods are distributed gradiently along the thickness of the shielding layer. Through the synergistic effect of dielectric loss and magnetic loss, the shielding effect is significantly improved across a wide frequency range from low to high frequencies. 3. The present invention achieves superhydrophobic and superoleophobic properties by chemically cross-linking the fluorosilane in the amphiphobic treatment layer with the surface-modified silica aerogel, forming a micro-nano composite rough structure. Combined with low surface energy materials, the structure achieves superhydrophobic and superoleophobic properties. Furthermore, the bonding strength between the aerogel and the substrate is enhanced by using an epoxy silane coupling agent. Combined with a gradient curing process, the amphiphobic properties remain stable even after multiple washings or frictions. 4. The present invention inhibits the peeling of the functional layer through the anchoring effect of nanocellulose crystals in the transition layer, combined with the surface activation effect of plasma activation treatment, significantly improving the interfacial bonding strength and environmental aging resistance between the functional layers. The electrospinning process adopts multi-level voltage regulation to achieve uniform thickness and composition gradient distribution of the functional layer, avoiding performance degradation caused by structural mutation in traditional processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram of the preparation process of the present invention; Figure 2 It is a three-dimensional schematic diagram of the overall structure of the present invention; Figure 3 It is a schematic cross-sectional view of the present invention; In the figure: 1. Base material layer; 2. Shielding function layer; 3. Amphiphobic treatment layer. DETAILED DESCRIPTION

[0017] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not 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 efforts are within the scope of protection of the present invention.

[0018] In the description of the present invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," "the other end," and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0019] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "provided with," "connected," etc., should be understood in a broad sense. For example, "connected" may refer to a fixed connection, a detachable connection, or an integral connection; it may refer to a mechanical connection or an electrical connection; it may refer to a direct connection or an indirect connection through an intermediate medium; it may refer to internal communication between two components. Those skilled in the art will be able to understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0020] Example 1: Please refer to Figure 1 、 Figure 2 and Figure 3 The present invention provides an embodiment of a high-shielding medical fabric based on surface amphiphobic treatment technology, comprising a base material layer 1, a shielding function layer 2, and an amphiphobic treatment layer 3 arranged in sequence from bottom to top. The base material layer 1 is a warp-knitted structure formed by blending polyvinyl chloride fiber and polyester fiber in a ratio of 4:6. The polyvinyl chloride fiber is treated with a sulfonated modification solution, and the surface grafting rate is 12%. The polyester fiber is doped with 0.3wt% carbon nanotube / graphene oxide hybrid material. When the hybrid material doping amount is 0.3wt%, the surface resistivity is 10^3Ω / sq, and when the hybrid material doping amount is 0.5wt%, the surface resistivity is 10^2Ω / sq. The shielding function layer 2 is a nanosilver / polyurethane composite film loaded on the surface of the substrate layer 1 by an electrospinning process. The thickness is 125 μm, of which the nanosilver accounts for 2% by weight and has a particle size of 35 nm. It is also composited with titanium dioxide nanorods with an aspect ratio of 18:1, and the mass ratio of titanium dioxide nanorods to nanosilver is 1:4; The ambiphobic treatment layer 3 is formed by vapor deposition of a modified solution of perfluoroalkyltriethoxysilane and hexadecyltrimethoxysilane in a ratio of 1:3, and hydrophobic silica aerogel particles with a mass fraction of 15% of fluorosilane are added, with a water contact angle of ≥150° and an oil contact angle of ≥140°; 3 wt% of 2,3-epoxypropyltrimethylammonium chloride was added to the sulfonated modified solution to simultaneously graft quaternary ammonium groups onto the fiber surface, and the Zeta potential of the fiber surface was +23 mV; In the shielding function layer 2, nanosilver is gradiently dispersed by polyvinyl pyrrolidone, and titanium dioxide nanorods are gradiently distributed along the thickness direction of the film; The hydrophobic silica aerogel particles in the amphiphobic treatment layer 3 have a particle size of 75 nm and are surface-modified with perfluorodecyltriethoxysilane, which is cross-linked with fluorosilane via siloxane bonds. The polyester fiber surface of the substrate layer 1 is provided with a micron-scale groove structure with a groove depth of 1.3 μm and a width of 2 μm, and a depth-to-width ratio of 1:1.8. The carbon nanotubes or graphene oxide are directionally arranged along the grooves. A transition layer is provided between the shielding functional layer 2 and the amphiphobic treatment layer 3. The transition layer is made of a polydopamine / chitosan composite membrane with a thickness of 8 μm and contains 0.3 wt% of nanocellulose crystals. The nanocellulose crystals are a composite of cerium dioxide and zinc oxide with a particle size of ≤100 nm. The preparation steps of the high-shielding medical fabric based on surface amphiphobic treatment technology are as follows: S1. Substrate pretreatment: immerse the polyvinyl chloride / polyester blended fabric in an ethanol solution containing 7 wt% sodium hydroxide and ultrasonically treat at 50°C for 45 min; S2. Shielding layer construction: A polyurethane spinning solution containing 0.3 M silver nitrate and titanium dioxide nanorods was prepared, and electrospinning was performed using multi-stage voltage control with an initial voltage of 12 kV and a linear increase to 22 kV within 10 min; S3, UV reduction: irradiate with a 365nm UV light source for 45min, and introduce nitrogen protection with an oxygen concentration of ≤50ppm, and adjust the nanosilver (111) crystal plane index and the nanosilver (200) crystal plane index to a ratio of 3.2:1; S4, plasma activation: Argon plasma treatment, with a power of 300W and a time of 6 minutes, which increases the surface oxygen content by 6%; S5. Amphiphobic treatment: immerse the activated substrate in an isopropyl alcohol solution containing 2 wt% fluorosilane, 0.06 wt% erucamide, and hydrophobic silica aerogel, and heat it up at a gradient rate of 5°C / min to 80°C for 10 min, then to 150°C at a rate of 3°C / min, and cure for 45 min. In step S2, titanium dioxide nanorods are prepared by a hydrothermal method, the reaction system includes 0.2M tetrabutyl titanate and 2M hydrochloric acid, the reaction temperature is 170°C, and the reaction time is 18 hours; The surface oxidation degree of the nanosilver after ultraviolet reduction in step S3 is ≤5%, and a Z-shaped heterostructure is formed between the nanosilver and the titanium dioxide nanorods; In step S5, 0.15 wt % of epoxy silane coupling agent is further added to the isopropyl alcohol solution to enhance the interfacial bonding strength between the hydrophobic silica aerogel particles and the fluorosilane.

[0021] Example 2: Please refer to Figure 1 、 Figure 2 and Figure 3The present invention provides an embodiment of a high-shielding medical fabric based on surface amphiphobic treatment technology, comprising a base material layer 1, a shielding function layer 2, and an amphiphobic treatment layer 3 arranged in sequence from bottom to top, wherein the base material layer 1 is a warp-knitted structure formed by blending polyvinyl chloride fiber and polyester fiber in a ratio of 3:7, the polyvinyl chloride fiber is treated with a sulfonated modification solution, and the surface grafting rate is 15%, and 0.1wt% of a carbon nanotube / graphene oxide hybrid material is doped into the polyester fiber. When the hybrid material doping amount is 0.3wt%, the surface resistivity is 10^3Ω / sq, and when the hybrid material doping amount is 0.5wt%, the surface resistivity is 10^2Ω / sq; The shielding function layer 2 is a nanosilver / polyurethane composite film loaded on the surface of the substrate layer 1 by an electrospinning process. The thickness is 200 μm, of which the nanosilver accounts for 0.5% by weight and has a particle size of 50 nm. It is also composited with titanium dioxide nanorods with an aspect ratio of 15:1, and the mass ratio of titanium dioxide nanorods to nanosilver is 1:5; The ambiphobic treatment layer 3 is formed by vapor deposition of a modified solution of perfluoroalkyltriethoxysilane and hexadecyltrimethoxysilane in a ratio of 1:2, and hydrophobic silica aerogel particles with a weight ratio of 20% of fluorosilane are added, with a water contact angle of ≥150° and an oil contact angle of ≥140°; 2 wt% of 2,3-epoxypropyltrimethylammonium chloride was added to the sulfonated modified solution to simultaneously graft quaternary ammonium groups onto the fiber surface, and the Zeta potential of the fiber surface was +15 mV; In the shielding function layer 2, nanosilver is gradiently dispersed by polyvinyl pyrrolidone, and titanium dioxide nanorods are gradiently distributed along the thickness direction of the film; The hydrophobic silica aerogel particles in the ambiphobic treatment layer 3 have a particle size of 100 nm and are surface-modified with perfluorodecyltriethoxysilane, which is cross-linked with fluorosilane via siloxane bonds; The polyester fiber surface of the substrate layer 1 is provided with a micron-scale groove structure with a groove depth of 0.5 μm and a width of 3 μm, and a depth-to-width ratio of 1:1.5. The carbon nanotubes or graphene oxide are directionally arranged along the grooves; A transition layer is provided between the shielding function layer 2 and the amphiphobic treatment layer 3. The transition layer is made of a polydopamine / chitosan composite film with a thickness of 10 μm and contains 0.1 wt% of nanocellulose crystals. The nanocellulose crystals are a composite of cerium dioxide and zinc oxide with a particle size of ≤100 nm. The preparation steps of the high-shielding medical fabric based on surface amphiphobic treatment technology are as follows: S1. Substrate pretreatment: immerse the polyvinyl chloride / polyester blended fabric in an ethanol solution containing 8 wt% sodium hydroxide and ultrasonically treat at 50°C for 30 min; S2. Shielding layer construction: A polyurethane spinning solution containing 0.5 M silver nitrate and titanium dioxide nanorods was prepared, and electrospinning was performed using multi-stage voltage control with an initial voltage of 12 kV and a linear increase to 22 kV within 10 min; S3, UV reduction: irradiate with a 365nm UV light source for 30min, and introduce nitrogen protection with an oxygen concentration of ≤50ppm, and adjust the nanosilver (111) crystal plane index and the nanosilver (200) crystal plane index to a ratio of 3.8:1; S4, plasma activation: Argon plasma treatment, with a power of 200W and a time of 8 minutes, to increase the surface oxygen content by 5%; S5. Amphiphobic treatment: immerse the activated substrate in an isopropyl alcohol solution containing 3 wt% fluorosilane, 0.01 wt% erucamide, and hydrophobic silica aerogel, and heat it up at a gradient rate of 5°C / min to 80°C for 10 min, then to 150°C at a rate of 3°C / min, and cure for 60 min. In step S2, titanium dioxide nanorods are prepared by a hydrothermal method, the reaction system includes 0.1M tetrabutyl titanate and 3M hydrochloric acid, the reaction temperature is 160°C, and the reaction time is 24h; The surface oxidation degree of the nanosilver after ultraviolet reduction in step S3 is ≤5%, and a Z-shaped heterostructure is formed between the nanosilver and the titanium dioxide nanorods; In step S5, 0.05 wt % of epoxy silane coupling agent is further added to the isopropyl alcohol solution to enhance the interfacial bonding strength between the hydrophobic silica aerogel particles and the fluorosilane.

[0022] Example 3: Please refer to Figure 1 、 Figure 2 and Figure 3 The present invention provides an embodiment of a high-shielding medical fabric based on surface amphiphobic treatment technology, comprising a base material layer 1, a shielding function layer 2, and an amphiphobic treatment layer 3 arranged in sequence from bottom to top, wherein the base material layer 1 is a warp knitted structure formed by blending polyvinyl chloride fiber and polyester fiber in a ratio of 5:5, the polyvinyl chloride fiber is treated with a sulfonated modification solution, and the surface grafting rate is 8%, and 0.5wt% of a carbon nanotube / graphene oxide hybrid material is doped into the polyester fiber. When the hybrid material doping amount is 0.3wt%, the surface resistivity is 10^3Ω / sq, and when the hybrid material doping amount is 0.5wt%, the surface resistivity is 10^2Ω / sq. The shielding function layer 2 is a nanosilver / polyurethane composite film loaded on the surface of the substrate layer 1 by an electrospinning process. The thickness is 50 μm, of which the nanosilver accounts for 3% by weight and has a particle size of 20 nm. It is also composited with titanium dioxide nanorods with an aspect ratio of 20:1, and the mass ratio of titanium dioxide nanorods to nanosilver is 1:3; The ambiphobic treatment layer 3 is formed by vapor deposition of a modified solution of perfluoroalkyltriethoxysilane and hexadecyltrimethoxysilane in a ratio of 1:4, and hydrophobic silica aerogel particles with a mass ratio of 10% of fluorosilane are added, with a water contact angle of ≥150° and an oil contact angle of ≥140°; 5 wt% of 2,3-epoxypropyltrimethylammonium chloride was added to the sulfonated modified solution to simultaneously graft quaternary ammonium groups onto the fiber surface, and the Zeta potential of the fiber surface was +30 mV; In the shielding function layer 2, nanosilver is gradiently dispersed by polyvinyl pyrrolidone, and titanium dioxide nanorods are gradiently distributed along the thickness direction of the film; The hydrophobic silica aerogel particles in the ambiphobic treatment layer 3 have a particle size of 50 nm and are surface-modified with perfluorodecyltriethoxysilane, which is cross-linked with fluorosilane via siloxane bonds; The polyester fiber surface of the substrate layer 1 is provided with a micron-scale groove structure with a groove depth of 2 μm and a width of 1 μm, and a depth-to-width ratio of 1:2. The carbon nanotubes or graphene oxide are directionally arranged along the grooves. A transition layer is provided between the shielding functional layer 2 and the amphiphobic treatment layer 3. The transition layer is made of a polydopamine / chitosan composite membrane with a thickness of 5 μm and contains 0.5 wt% of nanocellulose crystals. The nanocellulose crystals are a composite of cerium dioxide and zinc oxide with a particle size of ≤100 nm. The preparation steps of the high-shielding medical fabric based on surface amphiphobic treatment technology are as follows: S1. Substrate pretreatment: immerse the polyvinyl chloride / polyester blended fabric in an ethanol solution containing 8 wt% sodium hydroxide and ultrasonically treat at 50°C for 30 min; S2. Shielding layer construction: A polyurethane spinning solution containing 0.5 M silver nitrate and titanium dioxide nanorods was prepared, and electrospinning was performed using multi-stage voltage control with an initial voltage of 12 kV and a linear increase to 22 kV within 10 min; S3, UV reduction: irradiate with a 365nm UV light source for 30min, and introduce nitrogen protection with an oxygen concentration of ≤50ppm, and adjust the nanosilver (111) crystal plane index and the nanosilver (200) crystal plane index to a ratio of 3.8:1; S4, plasma activation: Argon plasma treatment, with a power of 200W and a time of 8 minutes, to increase the surface oxygen content by 5%; S5. Amphiphobic treatment: immerse the activated substrate in an isopropyl alcohol solution containing 3 wt% fluorosilane, 0.01 wt% erucamide, and hydrophobic silica aerogel, and heat it up at a gradient rate of 5°C / min to 80°C for 10 min, then to 150°C at a rate of 3°C / min, and cure for 60 min. In step S2, titanium dioxide nanorods are prepared by a hydrothermal method, the reaction system includes 0.1M tetrabutyl titanate and 3M hydrochloric acid, the reaction temperature is 160°C, and the reaction time is 24h; The surface oxidation degree of the nanosilver after ultraviolet reduction in step S3 is ≤5%, and a Z-shaped heterostructure is formed between the nanosilver and the titanium dioxide nanorods; In step S5, 0.05 wt % of epoxy silane coupling agent is further added to the isopropyl alcohol solution to enhance the interfacial bonding strength between the hydrophobic silica aerogel particles and the fluorosilane.

[0023] Example 4: Please refer to Figure 1 、 Figure 2 and Figure 3 The present invention provides an embodiment of a high-shielding medical fabric based on surface amphiphobic treatment technology, comprising a base material layer 1, a shielding function layer 2, and an amphiphobic treatment layer 3 arranged in sequence from bottom to top. The base material layer 1 is a warp-knitted structure formed by blending polyvinyl chloride fiber and polyester fiber in a ratio of 5:5. The polyvinyl chloride fiber is treated with a sulfonated modification solution, and the surface grafting rate is 12%. The polyester fiber is doped with 0.2wt% carbon nanotube / graphene oxide hybrid material. When the hybrid material doping amount is 0.3wt%, the surface resistivity is 10^3Ω / sq, and when it is 0.5wt%, the surface resistivity is 10^2Ω / sq. The shielding function layer 2 is a nanosilver / polyurethane composite film loaded on the surface of the substrate layer 1 by an electrospinning process. The thickness is 98 μm, of which the nanosilver accounts for 0.1% by weight and has a particle size of 22 nm. It is also composited with titanium dioxide nanorods with an aspect ratio of 19:1, and the mass ratio of titanium dioxide nanorods to nanosilver is 1:5; The ambiphobic treatment layer 3 is formed by vapor deposition of a modified solution of perfluoroalkyltriethoxysilane and hexadecyltrimethoxysilane in a ratio of 1:4, and hydrophobic silica aerogel particles with a mass fraction of 18% of fluorosilane are added, with a water contact angle of ≥150° and an oil contact angle of ≥140°; 4 wt% of 2,3-epoxypropyltrimethylammonium chloride was added to the sulfonated modified solution to simultaneously graft quaternary ammonium groups onto the fiber surface, and the Zeta potential of the fiber surface was +26 mV; In the shielding function layer 2, nanosilver is gradiently dispersed by polyvinyl pyrrolidone, and titanium dioxide nanorods are gradiently distributed along the thickness direction of the film; The hydrophobic silica aerogel particles in the ambiphobic treatment layer 3 have a particle size of 88 nm and are surface-modified with perfluorodecyltriethoxysilane, which is cross-linked with fluorosilane via siloxane bonds; The polyester fiber surface of the substrate layer 1 is provided with a micron-scale groove structure with a groove depth of 0.6 μm and a width of 1 μm, and a depth-to-width ratio of 1:2. The carbon nanotubes or graphene oxide are directionally arranged along the grooves. A transition layer is provided between the shielding functional layer 2 and the amphiphobic treatment layer 3. The transition layer is made of a polydopamine / chitosan composite membrane with a thickness of 8 μm and contains 0.4 wt% of nanocellulose crystals. The nanocellulose crystals are a composite of cerium dioxide and zinc oxide with a particle size of ≤100 nm. The preparation steps of the high-shielding medical fabric based on surface amphiphobic treatment technology are as follows: S1. Substrate pretreatment: immerse the polyvinyl chloride / polyester blended fabric in an ethanol solution containing 6 wt% sodium hydroxide and ultrasonically treat at 50°C for 35 min; S2. Shielding layer construction: A polyurethane spinning solution containing 0.4 M silver nitrate and titanium dioxide nanorods was prepared, and electrospinning was performed using multi-stage voltage control with an initial voltage of 12 kV and a linear increase to 22 kV within 10 min; S3, UV reduction: irradiate with a 365nm UV light source for 50min, and introduce nitrogen protection with an oxygen concentration of ≤50ppm, and adjust the nanosilver (111) crystal plane index and the nanosilver (200) crystal plane index to a ratio of 3.2:1; S4, plasma activation: Argon plasma treatment, with a power of 300W and a time of 7 minutes, increases the surface oxygen content by 7%; S5. Amphiphobic treatment: immerse the activated substrate in an isopropyl alcohol solution containing 1 wt% fluorosilane, 0.1 wt% erucamide, and hydrophobic silica aerogel, and heat it up at a gradient rate of 5°C / min to 80°C for 10 min, then to 150°C at a rate of 3°C / min, and cure for 55 min. In step S2, titanium dioxide nanorods are prepared by a hydrothermal method, the reaction system includes 0.1M tetrabutyl titanate and 2M hydrochloric acid, the reaction temperature is 170°C, and the reaction time is 18 hours; The surface oxidation degree of the nanosilver after ultraviolet reduction in step S3 is ≤5%, and a Z-shaped heterostructure is formed between the nanosilver and the titanium dioxide nanorods; In step S5, 0.1 wt % of epoxy silane coupling agent is further added to the isopropyl alcohol solution to enhance the interfacial bonding strength between the hydrophobic silica aerogel particles and the fluorosilane.

[0024] Comparative Example 1: A high-shielding medical fabric based on surface amphiphobic treatment technology was prepared according to the method of Example 1. The difference from Example 1 is that no nanocellulose crystals were added, and other raw materials, steps and parameters were the same as those in Example 1.

[0025] Comparative Example 2: A high-shielding medical fabric based on surface amphiphobic treatment technology was prepared according to the method of Example 1. The difference from Example 1 is that the polyvinyl chloride fiber was not sulfonated, and other raw materials, steps and parameters were the same as those in Example 1.

[0026] Comparative Example 3: A high-shielding medical fabric based on surface amphiphobic treatment technology was prepared according to the method of Example 1. The difference from Example 1 is that titanium dioxide nanorods were not added, and other raw materials, steps and parameters were the same as those in Example 1.

[0027] Comparative Example 4: A high-shielding medical fabric based on surface amphiphobic treatment technology was prepared according to the method of Example 1. The difference from Example 1 is that no hydrophobic silica aerogel particles were added, and other raw materials, steps and parameters were the same as those in Example 1.

[0028] Comparative Example 5: A high-shielding medical fabric based on surface amphiphobic treatment technology was prepared according to the method of Example 1. The difference from Example 1 is that 2,3-epoxypropyltrimethylammonium chloride was not added, and other raw materials, steps and parameters were the same as those in Example 1.

[0029] Comparative Example 6: A high-shielding medical fabric based on surface amphiphobic treatment technology was prepared according to the method of Example 1. The difference from Example 1 is that the multi-stage voltage regulation is cancelled and a constant voltage of 12 kV is adopted throughout the process. Other raw materials, steps and parameters are the same as those in Example 1.

[0030] Performance testing: Test 1: Antibacterial performance test: The high-shielding medical fabrics with surface ambiphobic treatment technology obtained in Examples 1-4 and Comparative Examples 1-6 were tested for their antibacterial rate against Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 6538) using GB / T 20944.3-2008 Evaluation of Antibacterial Properties of Textiles Part 3: Oscillation Method. The fabrics were cut into 5 cm × 5 cm specimens and sterilized under UV for 30 min. The specimens were immersed in a conical flask containing a bacterial solution (concentration 1×10^5 CFU / mL) and incubated at 37°C with shaking for 18 h. The bacterial solution was then diluted gradiently and applied to agar plates, incubated at 37°C for 24 h, and the number of colonies was counted to obtain the antibacterial rate.

[0031] Test 2: Electromagnetic Shielding Effectiveness (SE) Test: The high-shielding medical fabrics with surface amphiphobic treatment technology obtained in Examples 1-4 and Comparative Examples 1-6 were tested for shielding effectiveness using a vector network analyzer (frequency range 30 MHz–1.5 GHz) in accordance with ASTM D4935-18.

[0032] Test 3: Amphiphobicity test: The high-shielding medical fabrics with surface amphiphobic treatment technology obtained in Examples 1-4 and Comparative Examples 1-6 were tested for the contact angles of water (deionized water) and oil (hexadecane) using a contact angle meter (sessile drop method). The average value was obtained by measuring 5 points for each sample.

[0033] Test 4: Durability test: The high-shielding medical fabrics with surface amphiphobic treatment technology obtained in Examples 1-4 and Comparative Examples 1-6 were tested for antibacterial rate and shielding efficiency retention after 50 simulated home washings with reference to the AATCC 61-2013 standard.

[0034]

[0035]

[0036] Furthermore, sulfonic acid groups are introduced into polyvinyl chloride fibers through treatment with a sulfonation modification solution, and quaternary ammonium groups are grafted via a ring-opening reaction of epoxy groups to form a positive surface, thereby destroying bacterial cell membranes through electrostatic adsorption, thereby achieving an antibacterial effect; The Z-shaped heterostructure is formed by combining the silver nanoparticles in the shielding functional layer 2 with the titanium dioxide nanorods. The silver nanoparticles release anions to directly kill bacteria, and the titanium dioxide nanorods generate active oxygen under ultraviolet light. The Z-shaped heterostructure improves the carrier separation efficiency, thereby synergistically enhancing the sterilization effect. Nanocellulose crystals in the transition layer photocatalytically degrade bacterial metabolites, inhibiting biofilm formation and maintaining long-term surface cleanliness. The silver nanoparticles in the shielding layer are gradiently dispersed through polyvinyl pyrrolidone. Electrospinning adopts multi-level voltage regulation, which can form a high-density conductive network in the thickness direction of the film through gradient voltage regulation, thereby reducing the surface resistivity. By distributing titanium dioxide nanorods and silver nanoparticles in a gradient along the thickness direction of the film, titanium dioxide nanorods and silver nanoparticles form a Z-shaped heterojunction, which can enhance electromagnetic wave absorption through the interface polarization effect; The amphiphobic treatment layer 3 is a compound of perfluoroalkyltriethoxysilane and hexadecyltrimethoxysilane. The fluorosilane reduces the surface energy, and the aerogel locks the air layer through the micro-nano rough structure to ensure that the water contact angle is ≥150°. Quaternary ammonium groups are introduced through sulfonation modification to form a positively charged surface, enhancing bacterial adsorption capacity. The nanosilver in the shielding functional layer 2 exerts a contact bactericidal effect through ion release. The photocatalytic activity of the composite titanium dioxide nanorods can generate reactive oxygen free radicals, achieving a physical-chemical-photocatalytic triple antibacterial synergistic effect. The proportion of nanosilver crystal faces is then precisely controlled through an ultraviolet reduction process to expose highly catalytically active crystal faces. Combined with the heterojunction structure design, the photoresponse efficiency and antibacterial durability are significantly improved. The carbon nanotubes / graphene oxide in substrate layer 1 are directionally arranged along the fiber grooves to form micron-scale conductive pathways. The gradient-dispersed silver nanoparticles in the shielding layer form a nanoscale conductive network. The two work together to achieve a dual shielding mechanism of electromagnetic wave reflection and absorption. The titanium dioxide nanorods are gradiently distributed along the thickness of the shielding layer. Through the synergistic effect of dielectric loss and magnetic loss, the shielding effect is significantly improved across a wide frequency range from low to high frequencies. In the amphiphobic treatment layer 3, the fluorosilane and the surface-modified silica aerogel are cross-linked through chemical bonds to form a micro-nano composite rough structure. Combined with low surface energy materials, it achieves superhydrophobic and superoleophobic properties. The epoxy silane coupling agent is used to enhance the bonding strength between the aerogel and the substrate. Combined with a gradient curing process, the amphiphobic properties are ensured to remain stable after multiple washings or frictions. By inhibiting the delamination of the functional layer through the anchoring effect of nanocellulose crystals in the transition layer, combined with the surface activation effect of plasma activation treatment, the interfacial bonding strength and environmental aging resistance between the functional layers are significantly improved. The electrospinning process adopts multi-level voltage regulation to achieve uniform thickness and gradient distribution of the functional layer, avoiding the performance degradation caused by structural mutation in traditional processes. The polydopamine / chitosan transition layer combines bioadhesion and antibacterial properties, avoiding excessive release of metal ions and ensuring biosafety in medical scenarios. Hydrothermal synthesis of titanium dioxide nanorods and ultraviolet reduction of nanosilver reduce the use of chemical reducing agents and reduce environmental load. Through the coordinated design of sulfonated polyvinyl chloride fibers and directional conductive fillers with polyester fiber groove structures, the antibacterial properties and conductivity of the substrate are simultaneously improved. The Z-shaped heterostructure formed by nanosilver and titanium dioxide nanorods significantly improves the carrier separation efficiency, broadens the light response range to the visible light region, and reduces dependence on ultraviolet light sources.

[0037] Working principle: quaternary ammonium salt groups are introduced through sulfonation modification to form a positively charged surface, enhance the bacterial adsorption capacity, and the nanosilver in the shielding functional layer 2 exerts a contact bactericidal effect through ion release. The photocatalytic activity of the composite titanium dioxide nanorods can produce active oxygen free radicals, realizing the physical-chemical-photocatalytic triple antibacterial synergistic effect. Then, the proportion of nanosilver crystal faces is precisely controlled through the ultraviolet reduction process to expose the high catalytic activity crystal faces. Combined with the heterojunction structure design, the light response efficiency and antibacterial durability are significantly improved. The carbon nanotubes / graphene oxide in the substrate layer 1 are fixed along the fiber grooves. The shielding layer is arranged in a micron-scale conductive path, and the gradient-dispersed nanosilver in the shielding layer forms a nanoscale conductive network. The two work together to achieve a dual shielding mechanism of electromagnetic wave reflection and absorption. The titanium dioxide nanorods are gradiently distributed along the thickness direction of the shielding layer. Through the synergistic effect of dielectric loss and magnetic loss, the shielding effect from low frequency to high frequency wide band is significantly improved. The fluorosilane and the surface-modified silica aerogel in the double-repellent treatment layer 3 are cross-linked by chemical bonds to form a micro-nano composite rough structure, which is combined with low surface energy materials to achieve super hydrophobic and super oleophobic properties, and by using epoxy silane A coupling agent enhances the bond strength between the aerogel and the substrate. Combined with a gradient curing process, the amphiphobic properties remain stable even after repeated washing or friction. Nanocellulose crystals in the transition layer inhibit functional layer delamination through an anchoring effect. Combined with the surface activation effect of plasma activation, the interfacial bonding strength and environmental aging resistance of the functional layers are significantly improved. Multi-level voltage regulation is used in the electrospinning process to achieve uniform thickness and gradient composition distribution in the functional layers, avoiding the performance degradation caused by structural mutations in traditional processes. The polydopamine / chitosan transition layer combines bioadhesion and antibacterial properties, preventing excessive metal ion release and ensuring biosafety in medical settings. Hydrothermal synthesis of titanium dioxide nanorods and UV-reduced silver nanoparticles reduce the use of chemical reducing agents and lower environmental impact. The synergistic design of polyvinyl chloride fiber sulfonation and the inclusion of a directional conductive filler in a polyester fiber groove structure simultaneously enhances the substrate's antibacterial and electrical conductivity. The Z-shaped heterostructure formed by the silver nanoparticles and titanium dioxide nanorods significantly improves carrier separation efficiency, broadens the photoresponse range to the visible light region, and reduces dependence on UV light sources.

[0038] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A high-shielding medical fabric based on surface ambiphobic treatment technology, comprising a base material layer (1), a shielding function layer (2) and an ambiphobic treatment layer (3) arranged in sequence from bottom to top, characterized in that: The substrate layer (1) is a warp knitted structure formed by blending polyvinyl chloride fibers and polyester fibers in a ratio of 3:7-5:5, the polyvinyl chloride fibers are treated with a sulfonation modification solution, and the surface grafting rate is 8% to 15%, the polyester fibers are doped with 0.1-0.5wt% carbon nanotube / graphene oxide hybrid material, and the surface resistivity is 10^3Ω / sq when the doping amount of the hybrid material is 0.3wt%, and 10^2Ω / sq when the doping amount of the hybrid material is 0.5wt%; The shielding function layer (2) is a nanosilver / polyurethane composite film loaded on the surface of the substrate layer (1) by an electrospinning process, with a thickness of 50-200 μm, wherein the nanosilver accounts for 0.5% to 3% by weight, has a particle size of 20-50 nm, and is composited with titanium dioxide nanorods with an aspect ratio of 15:1-20:1, and the mass ratio of titanium dioxide nanorods to nanosilver is 1:3-1:5; The amphiphobic treatment layer (3) is formed by vapor deposition of a modified solution of perfluoroalkyltriethoxysilane and hexadecyltrimethoxysilane in a ratio of 1:2-1:4, and hydrophobic silica aerogel particles are added in an amount of 10% to 20% by weight of fluorosilane, with a water contact angle of ≥150° and an oil contact angle of ≥140°.

2. The high-shielding medical fabric based on surface amphiphobic treatment technology according to claim 1, characterized in that: 2-5 wt% of 2,3-epoxypropyltrimethylammonium chloride is added to the sulfonated modified solution to simultaneously graft quaternary ammonium salt groups onto the fiber surface, and the Zeta potential of the fiber surface is +15 mV to +30 mV.

3. The high-shielding medical fabric based on surface amphiphobic treatment technology according to claim 1, characterized in that: The nanosilver in the shielding functional layer (2) is gradient dispersed by polyvinyl pyrrolidone, and the titanium dioxide nanorods are distributed in a gradient along the thickness direction of the film.

4. The high-shielding medical fabric based on surface amphiphobic treatment technology according to claim 1, characterized in that: The particle size of the hydrophobic silica aerogel particles in the amphiphobic treatment layer (3) is 50-100 nm, and the surface is modified with perfluorodecyltriethoxysilane, which is cross-linked with fluorosilane through siloxane bonds.

5. The high-shielding medical fabric based on surface amphiphobic treatment technology according to claim 1, characterized in that: The polyester fiber surface of the substrate layer (1) is provided with a micron-scale groove structure, the groove depth is 0.5-2 μm, the width is 1-3 μm, and the depth to width ratio is 1:1.5-1:2, and the carbon nanotubes or graphene oxide are directionally arranged along the groove.

6. The high-shielding medical fabric based on surface amphiphobic treatment technology according to claim 1, characterized in that: A transition layer is provided between the shielding functional layer (2) and the amphiphobic treatment layer (3). The transition layer adopts a polydopamine / chitosan composite film with a thickness of 5-10 μm and contains 0.1-0.5 wt% of nanocellulose crystals. The nanocellulose crystals are a composite of cerium dioxide and zinc oxide with a particle size of ≤100 nm.

7. A method for preparing a high-shielding medical fabric based on surface amphiphobic treatment technology according to any one of claims 1 to 6, characterized in that: The preparation steps of the high-shielding medical fabric based on surface amphiphobic treatment technology are as follows: S1. Substrate pretreatment: immerse the polyvinyl chloride / polyester blended fabric in an ethanol solution containing 5-8 wt% sodium hydroxide and ultrasonically treat at 50°C for 30-60 min; S2. Shielding layer construction: A polyurethane spinning solution containing 0.1-0.5 M silver nitrate and titanium dioxide nanorods was prepared, and electrospinning was performed using multi-stage voltage control with an initial voltage of 12 kV and a linear increase to 22 kV within 10 min; S3, UV reduction: irradiate with a 365nm UV light source for 30-60min, and introduce nitrogen protection with an oxygen concentration of ≤50ppm, and adjust the nanosilver (111) crystal plane index and the nanosilver (200) crystal plane index to a ratio of 2.5-3.8:1; S4, plasma activation: Argon plasma treatment, the power is 200 ~ 400W, the time is 3 ~ 8 minutes, so that the surface oxygen content increases by 5% ~ 8%; S5. Amphiphobic treatment: Immerse the activated substrate in an isopropyl alcohol solution containing 1-3wt% fluorosilane, 0.01-0.1wt% erucamide and hydrophobic silica aerogel, and use a gradient temperature increase program. The temperature increase process is 5℃ / min to 80℃ and kept for 10 minutes, then increased to 150℃ at 3℃ / min, and cured for 30-60 minutes.

8. The method for preparing a high-shielding medical fabric based on surface amphiphobic treatment technology according to claim 7, characterized in that: In step S2, the titanium dioxide nanorods are prepared by a hydrothermal method, the reaction system includes 0.1-0.3M tetrabutyl titanate and 1-3M hydrochloric acid, the reaction temperature is 160-180°C, and the reaction time is 12-24 hours.

9. The method for preparing a high-shielding medical fabric based on surface amphiphobic treatment technology according to claim 7, characterized in that: The surface oxidation degree of the nanosilver after ultraviolet reduction in step S3 is ≤5%, and a Z-shaped heterostructure is formed between the nanosilver and the titanium dioxide nanorods.

10. The method for preparing a high-shielding medical fabric based on surface amphiphobic treatment technology according to claim 7, characterized in that: In step S5, 0.05-0.2 wt % of an epoxy silane coupling agent is further added to the isopropyl alcohol solution to enhance the interfacial bonding strength between the hydrophobic silica aerogel particles and the fluorosilane.

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