A graphene-based conductive textile fabric and a method for preparing the same

Abstract

The application belongs to the technical field of conductive fabric, and relates to a graphene-based conductive textile fabric and a preparation method thereof. The fabric comprises a composite polyurethane-based film, a bonding layer and a modified graphene conductive layer which are stacked in sequence. The composite polyurethane-based film is obtained by mixing polyurethane particles, stearic acid modified nano titanium dioxide and a lubricant, and then sequentially performing melt extrusion and blow molding film forming. The bonding layer is formed by coating a composite adhesive on the surface of the composite polyurethane-based film, and then drying and curing. The modified graphene conductive layer is formed by coating a modified graphene dispersion liquid on the surface of the bonding layer, and then drying, curing and hot pressing. The modified graphene is obtained by sequentially performing acid activation, dopamine coating modification, glutaraldehyde cross-linking modification and polyaniline monomer polymerization coating modification on graphene powder. Through the multilayer composite structure of the composite polyurethane-based film, the functionalized bonding layer and the modified graphene conductive layer, the conductive textile fabric realizes the common optimization of high conductivity, environmental resistance and mechanical flexibility.

Description

Technical Field

[0001] This invention belongs to the field of conductive fabric technology, and relates to a graphene-based conductive textile fabric and its preparation method. Background Technology

[0002] With the popularization of smart wearable technology, traditional conductive textile materials are gradually showing their shortcomings in terms of performance and functional integration. Although metal fibers have excellent conductivity, they are prone to oxidation and have poor flexibility, and the conductive pathways are easily broken after long-term bending. Conductive polymer materials such as polyaniline are easily affected by environmental temperature and humidity, and there is a risk of molecular degradation. Carbon fiber materials have anisotropic conductive networks due to the disordered distribution of layers, making it difficult to achieve uniform resistance characteristics. Existing technologies mostly rely on physical coating or chemical vapor deposition. The former sacrifices the breathability and feel of textiles, while the latter is difficult to mass-produce due to the conflict between high-temperature processes and fiber thermal stability, thus restricting the practical application value of conductive fabrics.

[0003] Graphene, with its single-atom-layer two-dimensional structure, ultra-high conductivity, and mechanical strength, offers a new direction for constructing novel conductive textiles. However, its stable bonding with the textile matrix remains a technical challenge. Conventional solution impregnation methods easily cause graphene sheets to stack, forming "island-like" conductive regions, whose performance degrades sharply after washing or friction. Chemical reduction methods generate process pollution that contradicts the greening trend of the textile industry. Existing research focuses primarily on improving conductivity, neglecting the mechanical adaptability and functional extensibility of textiles, making it difficult for products to simultaneously achieve derivative functions such as intelligent response and electromagnetic shielding, as well as wearing comfort. The fields of medical monitoring and sports health place higher demands on conductive fabrics: electrocardiogram monitoring requires biocompatibility and signal stability, while traditional silver-plated fabrics pose a risk of metal ion migration; under dynamic stretching scenarios, the carbon nanotube coating undergoes irreversible structural damage, leading to resistance drift and affecting the accuracy of physiological signal acquisition.

[0004] Therefore, there is an urgent need to develop a new process for multi-scale synergy between graphene and textile fibers, which can construct a three-dimensional stable conductive network while maintaining the softness and breathability of the fabric, and simultaneously solve core issues such as environmental friendliness, durability and multi-functional integration, so as to promote the practical application of smart textiles. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a graphene-based conductive textile fabric and its preparation method. The conductive textile fabric provided by the present invention achieves synergistic optimization of high conductivity, environmental resistance, and mechanical flexibility through a multi-layer composite structure of a composite polyurethane base film, a functionalized adhesive layer, and a modified graphene conductive layer. It can be widely used in the fields of smart wearable devices, medical sensing clothing, and electromagnetic shielding materials, and has significant industrialization value.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a graphene-based conductive textile fabric, the conductive textile fabric comprising a composite polyurethane base film, an adhesive layer and a modified graphene conductive layer stacked sequentially.

[0008] The composite polyurethane-based film is obtained by mixing polyurethane particles, stearic acid-modified nano-titanium dioxide and lubricant, and then sequentially melting and extruding and blow molding to form a film.

[0009] The adhesive layer is formed by coating the surface of the composite polyurethane base film with a composite adhesive and then drying and curing it. The composite adhesive includes epoxy resin emulsion, polyvinylpyrrolidone, curing agent and carboxylated nanowires.

[0010] The modified graphene conductive layer is formed by coating the surface of the adhesive layer with a modified graphene dispersion, followed by drying, curing, and hot pressing. The modified graphene dispersion is composed of modified graphene and a composite solvent. The modified graphene is obtained by sequentially modifying graphene powder through acid activation, dopamine coating modification, glutaraldehyde crosslinking modification, and polyaniline monomer polymerization coating modification.

[0011] The conductive textile fabric provided by this invention achieves synergistic optimization of high conductivity, environmental resistance, and mechanical flexibility through a multi-layer composite structure consisting of a composite polyurethane base film, a functionalized adhesive layer, and a modified graphene conductive layer. The stearic acid-modified nano-titanium dioxide-reinforced composite polyurethane base film forms a microporous structure during blow molding, balancing breathability and bending resistance, thus solving the problem of stiffness and easy breakage in traditional metal fiber conductive fabrics. The three-dimensional adhesive network constructed from carboxylated nanowires and epoxy resin strengthens the interfacial bonding strength between the composite polyurethane base film and the modified graphene conductive layer through both chemical bonding and mechanical interlocking, effectively resisting interlayer delamination caused by repeated bending and washing. The graphene conductive layer, modified by acid activation, polydopamine coating, and polyaniline polymerization, forms a "core-shell-crosslinked" composite structure, retaining the intrinsic high conductivity of graphene while suppressing sheet slippage through flexible polymer coating, achieving a stable conductive network under dynamic stress. The conductive textile fabric obtained by this invention retains the soft touch of natural fabrics while possessing excellent conductivity and mechanical properties. It can be widely used in smart wearable devices, medical sensing clothing, and electromagnetic shielding materials, and has significant industrialization value.

[0012] The composite polyurethane base film serves as the substrate for the entire conductive textile fabric, providing structural support and mechanical cushioning for the composite fabric system. While polyurethane itself possesses excellent elastic recovery, it is prone to irreversible deformation under repeated stretching when formed alone. This invention addresses this by introducing stearic acid-modified nano-titanium dioxide particles, simultaneously ensuring both the mechanical strength and flexibility of the base film. The stearic acid-modified nano-titanium dioxide is uniformly distributed within the polyurethane molecular chain network, forming a composite structure similar to reinforced concrete. The long-chain alkyl groups of stearic acid on the surface of the modified nano-titanium dioxide form an interpenetrating network with the polyurethane molecular chains through physical entanglement. Simultaneously, its surface hydroxyl groups form hydrogen bonds with the amino groups in the polyurethane. This dual effect enhances the tensile strength of the base film while preserving the overall flexibility of the material. During melt extrusion, the synergistic effect of the lubricant effectively reduces the molecular chain friction resistance during processing, allowing the melt extrusion process to be completed within a relatively mild temperature range. This avoids the impact of high temperatures on the heat sensitivity of polyurethane, ensuring that the surface smoothness of the base film obtained after blow molding meets the requirements for uniform adhesion of the functional coating. The microporous structure formed during the blow molding process allows air to pass through, ensuring the moisture permeability and breathability of the fabric base. At the same time, the 30-40μm thickness design not only meets the mechanical support requirements of the base film and provides a high-strength, flat support interface for subsequent functional layers, but also avoids the hardening of the touch caused by an excessively thick base film.

[0013] The adhesive layer is mainly used to connect the composite polyurethane base film and the modified graphene conductive layer. The continuous phase formed by the epoxy resin emulsion generates a three-dimensional cross-linked network after curing. The addition of polyvinylpyrrolidone not only improves the leveling properties during coating, but the pyrrolidone rings on its molecular chain can also form charge transfer complexes with the amino groups on the polyurethane surface. The introduction of carboxylated nanowires constructs a three-dimensional reinforcing network. The silicon carbide nanowires, treated with a combination of hydrogen peroxide and sodium hydroxide oxidation, have a large number of carboxylic acid groups on their surface. One end is bonded to the epoxy resin network through chemical bonds, while the exposed carboxylic acid groups at the other end provide active sites for the subsequent adhesion of the graphene layer. During the coating process, carboxylated nanowires exhibit partial directional alignment under shear force, forming vertical conductive microchannels extending from the composite polyurethane base film to the modified graphene conductive layer. This provides a high-speed charge transport pathway for the upper graphene conductive network, significantly reducing the anisotropy of in-plane resistance. Simultaneously, this structural design breaks through the limitations of traditional planar conductive layers. When the fabric is subjected to bending stress, the carboxylated nanowires absorb energy through their own bending deformation, preventing interlayer delamination caused by stress concentration at the interface.

[0014] The modified graphene conductive layer is the core functional layer of conductive textile fabrics. This invention first introduces oxygen-containing functional groups at the edges of graphene sheets through acid activation treatment, enhancing the surface reactivity of the graphene material and providing anchoring points for subsequent functional modifications. Subsequently, a polydopamine coating layer is formed on the graphene surface through dopamine self-polymerization. Dopamine not only adheres tightly to the graphene surface through π-π stacking, but the strong adhesion force generated by its catechol structure also ensures that the polydopamine coating layer remains intact under mechanical friction. Covalent connections are established between polydopamine molecules through glutaraldehyde crosslinking, forming a stable three-dimensional network structure that effectively inhibits the sliding displacement and stacking aggregation of graphene sheets. Finally, in-situ polymerization of aniline monomers was carried out under the action of an initiator, thereby constructing a conductive polymer coating layer on the graphene surface. This not only retained the intrinsic high conductivity of graphene, but the outermost polyaniline coating also provided additional conductive pathways. The pseudocapacitive properties of polyaniline enhanced the charge storage capacity, enabling the conductive textile fabric to maintain a stable current output during dynamic stretching.

[0015] The synergistic effect of the three-layer structure achieves a balance between electrical conductivity and mechanical properties. The elastic deformation capability of the composite polyurethane base film is transferred to the modified graphene conductive layer through the adhesive layer. When the fabric is stretched by external force, the composite polyurethane base film first undergoes molecular chain extension, and the carboxylated nanowires in the adhesive layer bend and deform accordingly. The outermost graphene conductive network remains continuous under the extension of polyaniline segments. This stepwise deformation mechanism disperses macroscopic stress into each layer structure, avoiding the breakage of conductive pathways caused by excessive local stress. The stability of electrical conductivity depends on the construction of a multi-scale conductive network. Although the stearic acid-modified nano-titanium dioxide in the composite polyurethane base film is not conductive, its uniform distribution prevents excessive shrinkage of the polyurethane matrix. The vertical array of carboxylated nanowires in the adhesive layer forms a longitudinal conductive channel that runs through the thickness of the adhesive layer, compensating for the anisotropy caused by the horizontal orientation of the graphene sheets. The three-dimensional cross-linked structure of the modified graphene itself ensures that even if individual sheets break, electrons can still be conducted through the polyaniline coating layer. Furthermore, the synergistic protection of each layer forms multiple barriers, effectively preventing moisture erosion and ensuring that the fabric maintains a high level of conductivity even after multiple washes. The hydrophobic properties of the composite polyurethane base film prevent liquid water penetration, the epoxy resin network in the adhesive layer forms a physical barrier against water molecule diffusion, and the dense coating structure on the graphene surface prevents moisture from eroding the conductive materials. When the fabric comes into contact with sweat or undergoes washing, this layered protective system effectively slows down the rate at which water molecules penetrate into the conductive materials. The introduction of the hot-pressing process further strengthens the bonding strength between the layers. The high temperature softens the polyurethane surface layer, causing it to partially embed into the adhesive layer network. After cooling, a mechanically interlocking structure is formed. This combined effect of physical anchoring and chemical bonding significantly improves the interlayer peel strength of the fabric.

[0016] As a preferred technical solution of the present invention, the thickness of the composite polyurethane base film is 30-40 μm, for example, it can be 30 μm, 31 μm, 32 μm, 33 μm, 34 μm, 35 μm, 36 μm, 37 μm, 38 μm, 39 μm or 40 μm, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0017] In some alternative examples, the thickness of the adhesive layer is 8 to 10 μm, for example, it can be 8.0 μm, 8.2 μm, 8.4 μm, 8.6 μm, 8.8 μm, 9.0 μm, 9.2 μm, 9.4 μm, 9.6 μm, 9.8 μm or 10.0 μm, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0018] In some optional instances, the thickness of the modified graphene conductive layer is 10–15 μm, for example, 10 μm, 10.5 μm, 11 μm, 11.5 μm, 12 μm, 12.5 μm, 13 μm, 13.5 μm, 14 μm, 14.5 μm or 15 μm, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0019] In a second aspect, the present invention provides a method for preparing the graphene-based conductive textile fabric described in the first aspect, the method comprising:

[0020] (I) Modified nano-titanium dioxide is obtained by modifying nano-titanium dioxide with stearic acid. Polyurethane particles, the modified nano-titanium dioxide and lubricant are mixed to obtain a mixture. The mixture is then subjected to melt extrusion, granulation and blow molding to form a film to obtain the composite polyurethane base film.

[0021] (II) Silicon carbide nanowires are modified with hydrogen peroxide and sodium hydroxide to obtain carboxylated nanowires; epoxy resin emulsion, polyvinylpyrrolidone, the carboxylated nanowires, curing agent and deionized water are mixed evenly to obtain a composite adhesive; the composite adhesive is coated on the surface of the composite polyurethane base film, and the adhesive layer is formed after drying and curing.

[0022] (III) The graphene powder is activated and modified with a mixed acid solution, then coated and modified with a dopamine solution, and finally crosslinked and modified with a glutaraldehyde solution to obtain crosslinked coated graphene; the crosslinked coated graphene is then subjected to in-situ polymerization and coating modification with aniline monomer and ammonium persulfate solution to obtain polyaniline coated modified graphene.

[0023] (IV) The modified graphene is dispersed in a composite solvent and stirred at high speed to obtain a modified graphene dispersion. The modified graphene dispersion is coated on the surface of the adhesive layer and dried, cured and hot-pressed to form the modified graphene conductive layer, thereby obtaining the conductive textile fabric.

[0024] In the preparation of the composite polyurethane-based film, surface treatment of nano-titanium dioxide with stearic acid significantly improved the compatibility between nano-titanium dioxide and the polyurethane matrix. Stearic acid molecules encapsulate the nano-titanium dioxide through both physical adsorption and chemical bonding, preventing agglomeration and forming an interpenetrating network structure through the entanglement of long-chain alkyl groups with the polyurethane molecular chains. This modification allows the nano-titanium dioxide to be uniformly dispersed during subsequent melt extrusion, fully leveraging its mechanical reinforcing effect.

[0025] This invention introduces carboxylated nanowires as a reinforcing phase into the adhesive layer. The silicon carbide nanowire surface is selectively oxidized through the synergistic effect of hydrogen peroxide and sodium hydroxide, directionally generating carboxylic acid groups while preserving the integrity of the main silicon carbide nanowire structure. These surface functional groups not only chemically react with the epoxy groups in the epoxy resin but also form a three-dimensional cross-linked network with polyvinylpyrrolidone through hydrogen bonding. In the coating process, by controlling the drying and curing conditions, a gradient cross-linked structure is formed in the adhesive layer. Dense cross-linking is formed near the composite polyurethane base film to enhance interfacial bonding, while moderate cross-linking is maintained near the modified graphene conductive layer to preserve elasticity. This gradient structure design allows the adhesive layer to withstand the mechanical stress of daily use while providing stable support for the modified graphene conductive layer.

[0026] In the multi-level modification process of graphene, active sites are first introduced at the edges of graphene sheets through mixed acid treatment, laying the foundation for subsequent functionalization. The self-polymerization and coating process of dopamine is carried out in a weakly alkaline environment, forming a uniform polydopamine coating layer on the graphene surface through oxidative self-assembly. This biomimetic adhesion layer not only enhances the environmental stability of graphene but also provides abundant reaction sites. Glutaraldehyde crosslinking treatment establishes covalent connections between polydopamines, forming a stable three-dimensional network structure that effectively inhibits the slippage and stacking of graphene sheets. Finally, in-situ polymerization of polyaniline is carried out under acidic conditions, with aniline monomers growing epitaxially along the crosslinked network to form a continuous conductive polyaniline coating layer on the surface of the polydopamine coating. This core-shell structure design retains the intrinsic conductivity of graphene while enhancing its durability through the protective effect of the outer polymer layer.

[0027] During the coating stage, this invention employs a specially designed composite solvent for modified graphene. The synergistic effect of sodium dodecylbenzenesulfonate and polyvinylpyrrolidone effectively prevents secondary agglomeration of the modified graphene, while the optimized mixing ratio of ethanol and water ensures leveling during the spraying process. By adjusting the temperature, pressure, and time of the hot-pressing process, a tight bond between the layers is achieved. The hot-pressing temperature of 80–90°C activates the molecular motion of the polyurethane surface layer to achieve interfacial fusion while avoiding damage to the conductive layer of the modified graphene at high temperatures. The hot-pressing pressure of 6–8 MPa allows the graphene sheets to maintain their orientation while achieving tight stacking, forming continuous conductive pathways.

[0028] As a preferred technical solution of the present invention, in step (I), the modified nano-titanium dioxide is prepared by the following method:

[0029] Stearic acid was dissolved in anhydrous ethanol, mixed and stirred and heated to obtain a stearic acid solution. Nano-titanium dioxide was mixed with the stearic acid solution and ball-milled, followed by filtration, washing and vacuum drying to obtain the modified nano-titanium dioxide.

[0030] In some optional instances, the mixing and stirring time of the stearic acid and anhydrous ethanol is 40 to 50 minutes, for example, 40 minutes, 41 minutes, 42 minutes, 43 minutes, 44 minutes, 45 minutes, 46 minutes, 47 minutes, 48 ​​minutes, 49 minutes or 50 minutes, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0031] In some alternative examples, the temperature at which the stearic acid and anhydrous ethanol are mixed and stirred is 60–70°C, for example, 60°C, 61°C, 62°C, 63°C, 64°C, 65°C, 66°C, 67°C, 68°C, 69°C or 70°C, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0032] In some alternative examples, the stearic acid in the stearic acid solution has a mass fraction of 3 to 4 wt%, for example, 3.0 wt%, 3.1 wt%, 3.2 wt%, 3.3 wt%, 3.4 wt%, 3.5 wt%, 3.6 wt%, 3.7 wt%, 3.8 wt%, 3.9 wt%, or 4.0 wt%, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0033] In some alternative examples, the mass ratio of the nano-titanium dioxide to the stearic acid in the stearic acid solution is 1:(0.15 to 0.25), for example, it can be 1:0.15, 1:0.16, 1:0.17, 1:0.18, 1:0.19, 1:0.2, 1:0.21, 1:0.22, 1:0.23, 1:0.24 or 1:0.25, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0034] This invention specifically defines the mass ratio of nano-titanium dioxide to stearic acid in the stearic acid solution as 1:(0.15~0.25). Within this ratio range, stearic acid molecules form a monolayer coating structure through chemical bonding between carboxyl groups and hydroxyl groups on the surface of nano-titanium dioxide. The number of stearic acid molecules adsorbed on the surface of each nano-titanium dioxide reaches a saturated coverage state, and the long-chain alkyl groups extend outward to form a steric hindrance effect. This modification method enables the nano-titanium dioxide to be uniformly dispersed during polyurethane melt extrusion, and the long chains of stearic acid and polyurethane molecular chains form physical entanglement, enhancing the interfacial bonding force between the modified nano-titanium dioxide and the polyurethane matrix.

[0035] When the amount of stearic acid is below the lower limit defined in this invention, the stearic acid is insufficient to completely cover the surface of the nano-titanium dioxide. The unmodified nano-titanium dioxide exposes a large number of hydroxyl groups, which undergo severe aggregation during high-temperature processing due to surface energy differences. This results in the formation of micron-sized aggregates in the polyurethane matrix, causing localized stress concentration during blow molding and leading to microcracks in the composite polyurethane film. Simultaneously, the exposed nano-titanium dioxide surface lacks effective connectivity with the polyurethane molecular chains, reducing interfacial shear strength and making it prone to peeling from the polyurethane matrix under external force.

[0036] When the amount of stearic acid exceeds the upper limit defined in this invention, excess stearic acid molecules form a multilayer adsorption on the surface of nano-titanium dioxide. These free stearic acids act as an internal lubricant during melt mixing, temporarily improving the fluidity of the material. However, after cooling and solidification, they form a weak interface layer between the polyurethane molecular chains. This structural defect reduces the tensile strength of the composite polyurethane film. Furthermore, at high temperatures, stearic acid molecules migrate to the surface and form precipitates, causing a decrease in the light transmittance of the composite polyurethane film. In addition, excess stearic acid also interferes with the microphase separation structure of polyurethane, reducing the crystallinity of the hard segments and causing a decrease in the glass transition temperature of the composite polyurethane film, making it more prone to creep deformation under dynamic loads.

[0037] In some optional examples, the ball milling speed for mixing the nano-titanium dioxide with the stearic acid solution is 250 to 350 rpm, for example, 250 rpm, 260 rpm, 270 rpm, 280 rpm, 290 rpm, 300 rpm, 310 rpm, 320 rpm, 330 rpm, 340 rpm or 350 rpm, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0038] In some optional examples, the ball milling time for mixing the nano-titanium dioxide with the stearic acid solution is 3 to 4 hours, for example, 3.0 hours, 3.1 hours, 3.2 hours, 3.3 hours, 3.4 hours, 3.5 hours, 3.6 hours, 3.7 hours, 3.8 hours, 3.9 hours, or 4.0 hours, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0039] In some optional instances, the vacuum drying temperature is 60–70°C, for example, 60°C, 61°C, 62°C, 63°C, 64°C, 65°C, 66°C, 67°C, 68°C, 69°C, or 70°C, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0040] In some optional instances, the vacuum drying time is 8 to 10 hours, for example, 8.0 hours, 8.2 hours, 8.4 hours, 8.6 hours, 8.8 hours, 9.0 hours, 9.2 hours, 9.4 hours, 9.6 hours, 9.8 hours, or 10.0 hours, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0041] As a preferred technical solution of the present invention, in step (I), the mass ratio of the polyurethane particles, the modified nano-titanium dioxide, and the lubricant is 100:(8-10):(1.5-2.5), for example, it can be 100:8:1.5, 100:8.2:1.6, 100:8.4:1.7, 100:8.6:1.8, 100:8.8:1.9, 100:9:2, 100:9.2:2.1, 100:9.4:2.2, 100:9.6:2.3, 100:9.8:2.4, or 100:10:2.5, but it is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0042] This invention specifically defines the mass ratio of polyurethane particles, modified nano-titanium dioxide, and lubricant as 100:(8-10):(1.5-2.5). When the amount of modified nano-titanium dioxide added is within this range, the stearic acid-modified nano-titanium dioxide is uniformly dispersed in the molten polyurethane matrix through the physical entanglement of the surface stearic acid organic long chains with the polyurethane molecular chains. The nano-titanium dioxide acts as a rigid reinforcing unit, forming physical cross-linking points in the soft segment region of the polyurethane, thus improving the creep resistance of the composite material. Simultaneously, it enhances the overall modulus of the composite material through stress transfer in the hard segment region. When an appropriate amount of modified nano-titanium dioxide is added, the composite polyurethane base film forms a stable interpenetrating network after blow molding. The modified nano-titanium dioxide will not damage the microphase separation structure of the polyurethane due to excessive aggregation, and it can effectively hinder molecular chain slippage through interfacial shearing. This allows it to withstand the mechanical stress of subsequent coating processes while maintaining the required soft and supple feel of the textile fabric.

[0043] When the amount of modified nano-titanium dioxide added is below the lower limit defined in this invention, the spatial distribution of modified nano-titanium dioxide in the polyurethane matrix is ​​too sparse, making it difficult to form a continuous reinforcing network. Insufficient physical cross-linking points between polyurethane molecular chains result in low melt strength of the composite material during the blow molding stage, and local thinning or bubble breakage is likely to occur during the blowing process. Furthermore, when the cured composite polyurethane film is subjected to external tensile force, the stress cannot be effectively transferred to the modified nano-titanium dioxide, affecting the mechanical strength of the textile fabric. Simultaneously, the sparsely distributed modified nano-titanium dioxide weakens its ability to prevent crack propagation, causing microcracks to easily form in the composite polyurethane film after repeated bending. This directly affects the adhesion stability of the upper modified graphene conductive layer, leading to a decrease in the interlayer bonding strength of the textile fabric.

[0044] When the amount of modified nano-titanium dioxide added exceeds the upper limit defined in this invention, the excessive modified nano-titanium dioxide agglomerates during the melt mixing process due to decreased interfacial compatibility. The steric hindrance effect provided by the stearic acid modified layer is broken, and the agglomerate size becomes a stress concentration point after exceeding the critical value. These micron-sized agglomerates hinder the regular arrangement of polyurethane molecular chains during blow molding, disrupting the continuity of the hard segment crystalline region, resulting in an abnormally high elastic modulus and a sharp decrease in toughness of the final composite polyurethane base film. In addition, excessive modified nano-titanium dioxide also increases the melt viscosity, requiring higher temperatures or pressures in the blow molding process, exacerbating the risk of thermal degradation of polyurethane.

[0045] In some optional instances, the lubricant comprises calcium stearate and / or zinc stearate.

[0046] In some alternative examples, the mixing temperature of the polyurethane particles, the modified nano-titanium dioxide, and the lubricant is 130–140°C, for example, 130°C, 131°C, 132°C, 133°C, 134°C, 135°C, 136°C, 137°C, 138°C, 139°C, or 140°C, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0047] In some optional examples, the mixing time of the polyurethane particles, the modified nano-titanium dioxide and the lubricant is 40 to 50 minutes, for example, 40 minutes, 41 minutes, 42 minutes, 43 minutes, 44 minutes, 45 minutes, 46 minutes, 47 minutes, 48 ​​minutes, 49 minutes or 50 minutes, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0048] In some alternative instances, the melt extrusion of the mixture is carried out in a screw extruder.

[0049] In some alternative examples, the barrel of the screw extruder is divided into a first zone, a second zone, and a third zone with different temperatures along the flow direction of the mixture.

[0050] In some optional instances, the temperature of the first zone is 165 to 175°C, for example, it can be 165°C, 166°C, 167°C, 168°C, 169°C, 170°C, 171°C, 172°C, 173°C, 174°C or 175°C, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0051] In some optional instances, the temperature of the second zone is 180–190°C, for example, 180°C, 181°C, 182°C, 183°C, 184°C, 185°C, 186°C, 187°C, 188°C, 189°C, or 190°C, but is not limited to the listed values; other unlisted values ​​within this range also apply.

[0052] In some optional instances, the temperature of the third zone is 195 to 205°C, for example, it can be 195°C, 196°C, 197°C, 198°C, 199°C, 200°C, 201°C, 202°C, 203°C, 204°C or 205°C, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0053] In some alternative instances, the screw speed of the screw extruder is 35 to 45 rpm, for example, 35 rpm, 36 rpm, 37 rpm, 38 rpm, 39 rpm, 40 rpm, 41 rpm, 42 rpm, 43 rpm, 44 rpm or 45 rpm, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0054] In some optional instances, the blow-up ratio of the blown film is (2.5 to 3.5):1, for example, it can be 2.5:1, 2.6:1, 2.7:1, 2.8:1, 2.9:1, 3.0:1, 3.1:1, 3.2:1, 3.3:1, 3.4:1 or 3.5:1, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0055] In some optional examples, the thickness of the composite polyurethane base film is 30 to 40 μm, for example, it can be 30 μm, 31 μm, 32 μm, 33 μm, 34 μm, 35 μm, 36 μm, 37 μm, 38 μm, 39 μm or 40 μm, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0056] As a preferred embodiment of the present invention, in step (II), the carboxylated nanowires are prepared by the following method:

[0057] A hydrogen peroxide solution and a sodium hydroxide solution were mixed evenly to obtain a modified solution. The silicon carbide nanowires were added to the modified solution, and after ultrasonic dispersion, they were transferred to a reaction vessel for high-temperature reaction. After the reaction was completed, the nanowires were filtered, washed with deionized water, and vacuum dried to obtain the carboxylated nanowires.

[0058] In some alternative examples, the hydrogen peroxide solution has a mass fraction of 6 to 8 wt%, for example, 6.0 wt%, 6.2 wt%, 6.4 wt%, 6.6 wt%, 6.8 wt%, 7.0 wt%, 7.2 wt%, 7.4 wt%, 7.6 wt%, 7.8 wt%, or 8.0 wt%, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0059] In some alternative examples, the sodium hydroxide solution has a mass fraction of 7 to 9 wt%, for example, 7.0 wt%, 7.2 wt%, 7.4 wt%, 7.6 wt%, 7.8 wt%, 8.0 wt%, 8.2 wt%, 8.4 wt%, 8.6 wt%, 8.8 wt%, or 9.0 wt%, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0060] In some alternative examples, the volume ratio of the hydrogen peroxide solution to the sodium hydroxide solution is 1:(1.3 to 1.5), for example, it can be 1:1.3, 1:1.32, 1:1.34, 1:1.36, 1:1.38, 1:1.4, 1:1.42, 1:1.44, 1:1.46, 1:1.48 or 1:1.5, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0061] In some alternative examples, the mass ratio of the silicon carbide nanowires to the modified solution is 1:(30-40), for example, 1:30, 1:31, 1:32, 1:33, 1:34, 1:35, 1:36, 1:37, 1:38, 1:39 or 1:40, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0062] In some alternative examples, the ultrasonic power for ultrasonic dispersion of the silicon carbide nanowires in the modified solution is 300 to 400 W, for example, 300 W, 310 W, 320 W, 330 W, 340 W, 350 W, 360 W, 370 W, 380 W, 390 W or 400 W, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0063] In some optional instances, the ultrasonic dispersion of the silicon carbide nanowires in the modified solution is ultrasonic for 40 to 50 minutes, for example, 40 minutes, 41 minutes, 42 minutes, 43 minutes, 44 minutes, 45 minutes, 46 minutes, 47 minutes, 48 ​​minutes, 49 minutes, or 50 minutes, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0064] In some alternative instances, the temperature of the high-temperature reaction is 120–130°C, for example, 120°C, 121°C, 122°C, 123°C, 124°C, 125°C, 126°C, 127°C, 128°C, 129°C, or 130°C, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0065] In some alternative examples, the high-temperature reaction time is 5 to 6 hours, for example, 5.0 hours, 5.1 hours, 5.2 hours, 5.3 hours, 5.4 hours, 5.5 hours, 5.6 hours, 5.7 hours, 5.8 hours, 5.9 hours, or 6.0 hours, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0066] As a preferred embodiment of the present invention, in step (II), the composite adhesive is prepared by the following method:

[0067] Epoxy resin emulsion, polyvinylpyrrolidone and curing agent are added to deionized water, mixed and stirred and heated to obtain a bonding base liquid; then carboxylated nanowires are added to the bonding base liquid and ultrasonically dispersed to obtain the composite adhesive.

[0068] In some alternative examples, the mass ratio of the epoxy resin emulsion, the polyvinylpyrrolidone, the curing agent, and the deionized water is (15–17):(1.5–2.5):(3–5):(80–90), for example, 15:1.5:3:80, 15.2:1.6:3.2:81, 15.4:1.7:3.4:82, 15.6:1.8:3.6:83, 15.8:1.9:3.8:84, 16:2:4:85, 16.2:2.1:4.2:86, 16.4:2.2:4.4:87, 16.6:2.3:4.6:88, 16.8:2.4:4.8:89, or 17:2.5:5:90, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0069] In some optional instances, the curing agent includes polyetheramine.

[0070] In some optional examples, the mixing and stirring time of the epoxy resin emulsion, the polyvinylpyrrolidone, the curing agent and the deionized water is 30 to 40 minutes, for example, 30 minutes, 31 minutes, 32 minutes, 33 minutes, 34 minutes, 35 minutes, 36 minutes, 37 minutes, 38 minutes, 39 minutes or 40 minutes, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0071] In some optional examples, the mixing temperature of the epoxy resin emulsion, the polyvinylpyrrolidone, the curing agent and the deionized water is 40 to 50°C, for example, 40°C, 41°C, 42°C, 43°C, 44°C, 45°C, 46°C, 47°C, 48°C, 49°C or 50°C, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0072] In some alternative instances, the mass fraction of the carboxylated nanowires in the composite binder is 3 to 4 wt%, for example, it may be 3.0 wt%, 3.1 wt%, 3.2 wt%, 3.3 wt%, 3.4 wt%, 3.5 wt%, 3.6 wt%, 3.7 wt%, 3.8 wt%, 3.9 wt%, or 4.0 wt%, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0073] This invention specifically limits the mass fraction of carboxylated nanowires in the composite adhesive to 3-4 wt%. Within this range, the carboxylated nanowires chemically bond with the epoxy groups of the epoxy resin through abundant carboxylic acid groups on their surface, and are uniformly dispersed in the adhesive matrix with the assistance of polyvinylpyrrolidone. During the curing process, the carboxylated nanowires form a three-dimensional network framework, and their axial high modulus effectively transfers interlayer stress, improving the shear strength of the adhesive layer. Appropriate addition of carboxylated nanowires ensures that they establish a continuous reinforcing network in the adhesive matrix without excessively increasing the system viscosity and affecting the coating uniformity of the composite adhesive.

[0074] When the amount of carboxylated nanowires added to the composite adhesive is less than 3 wt%, the distribution density of the carboxylated nanowires in the adhesive layer is insufficient to form an effective reinforcing network. The epoxy resin matrix mainly relies on the physical entanglement between molecular chains to transfer stress, and molecular chain slippage easily occurs under shear force. In addition, the excessively large spacing of the carboxylated nanowires prevents them from effectively bridging microcracks, and through-cracks easily form in the adhesive layer after repeated bending. At the same time, the number of carboxyl groups is insufficient to fully react with the epoxy resin, resulting in a low crosslinking density of the cured adhesive layer, a significant decrease in solvent resistance and resistance to humid heat aging, and easy interfacial delamination during water washing.

[0075] When the addition of carboxylated nanowires to the composite adhesive exceeds 4 wt%, the excess carboxylated nanowires undergo localized agglomeration within the adhesive. This agglomeration is accelerated, especially during the drying stage after coating, due to solvent evaporation. The resulting large agglomerates disrupt the continuous phase structure of the epoxy resin, creating internal stress concentration points and reducing the strength of the adhesive layer. Furthermore, the excess carboxylic acid groups compete with the curing agent, leading to incomplete curing. Simultaneously, the high content of carboxylated nanowires increases the viscosity of the composite adhesive, making it difficult to form a uniform and smooth film during transfer coating. This results in an uneven surface and pinhole defects in the final cured adhesive layer. Moreover, the rigid network formed by the excess carboxylated nanowires abnormally increases the elastic modulus of the adhesive layer, making it unable to adapt to the dynamic deformation during textile use, ultimately causing cracking or even detachment of the modified graphene conductive layer.

[0076] In some optional instances, the composite adhesive is applied by transfer coating.

[0077] In some optional examples, the coating speed of the composite adhesive is 10 to 12 m / min, for example, it can be 10 m / min, 10.2 m / min, 10.4 m / min, 10.6 m / min, 10.8 m / min, 11 m / min, 11.2 m / min, 11.4 m / min, 11.6 m / min, 11.8 m / min or 12 m / min, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0078] In some optional instances, the drying temperature after the composite adhesive is applied is 70–80°C, for example, 70°C, 71°C, 72°C, 73°C, 74°C, 75°C, 76°C, 77°C, 78°C, 79°C or 80°C, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0079] In some optional instances, the drying time after the composite adhesive is applied is 15 to 25 minutes, for example, 15 minutes, 16 minutes, 17 minutes, 18 minutes, 19 minutes, 20 minutes, 21 minutes, 22 minutes, 23 minutes, 24 minutes or 25 minutes, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0080] In some alternative instances, the curing temperature is 90 to 100°C, for example, 90°C, 91°C, 92°C, 93°C, 94°C, 95°C, 96°C, 97°C, 98°C, 99°C, or 100°C, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0081] In some optional instances, the curing time is 2 to 3 hours, for example, 2.0 hours, 2.1 hours, 2.2 hours, 2.3 hours, 2.4 hours, 2.5 hours, 2.6 hours, 2.7 hours, 2.8 hours, 2.9 hours, or 3.0 hours, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0082] In some alternative examples, the thickness of the adhesive layer is 8 to 10 μm, for example, it can be 8.0 μm, 8.2 μm, 8.4 μm, 8.6 μm, 8.8 μm, 9.0 μm, 9.2 μm, 9.4 μm, 9.6 μm, 9.8 μm or 10.0 μm, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0083] As a preferred technical solution of the present invention, in step (III), the cross-linked coated graphene is prepared by the following method:

[0084] (1) Mix nitric acid solution and sulfuric acid solution evenly to obtain the mixed acid solution, disperse the graphene powder in the mixed acid solution, mix and stir and heat to react, after the reaction is completed, centrifuge, wash with alkaline solution and vacuum dry to obtain activated graphene;

[0085] (2) Dissolve dopamine hydrochloride in Tris-HCl buffer to obtain a dopamine solution, disperse the activated graphene in the dopamine solution, mix and stir to produce a polymerization reaction, and after the reaction is completed, centrifuge, wash with deionized water and vacuum dry to obtain graphene coated with a polydopamine layer on the surface.

[0086] (3) Add glutaraldehyde to Tris-HCl buffer solution to obtain glutaraldehyde solution, add the coated graphene to the glutaraldehyde solution, mix and stir to cause cross-linking reaction, and after the reaction is completed, centrifuge, wash with deionized water and vacuum dry to obtain the cross-linked coated graphene.

[0087] This invention enhances the structural stability of graphene while maintaining its electrical conductivity through multi-stage chemical modification. In the mixed acid treatment stage, the synergistic effect of nitric acid and sulfuric acid selectively introduces oxygen-containing groups at the edges and surface defect sites of graphene sheets. The formation of these chemical groups enhances the surface activity of graphene. By controlling the reaction time and temperature, excessive damage to the main graphene structure is avoided. The activated graphene still retains its complete spline structure. 2 The hybrid carbon skeleton provides the main pathway for electron transport, while surface carboxyl groups and other functional groups provide anchoring sites for subsequent coating reactions, thus improving processing performance while maximizing the retention of its electrical conductivity.

[0088] During the dopamine coating stage, the weakly alkaline environment maintained by the Tris-HCl buffer system promotes the self-polymerization of dopamine molecules on the activated graphene surface. The polydopamine layer is tightly bound to the activated graphene through π-π stacking interactions, and the phenolic hydroxyl groups in its molecular chain form a hydrogen bond network with the carboxyl groups on the activated graphene surface. This coating structure forms a continuous organic layer covering the graphene surface, effectively blocking the erosion of the activated graphene by the environmental medium. Simultaneously, due to the semiconductor properties of polydopamine itself, its coating thickness is controlled at the nanoscale, avoiding complete blockage of electronic transitions between graphene sheets. The surface charge adjustment brought about by the polydopamine coating layer also improves the dispersion stability of graphene in the solution system, which is beneficial for forming a uniform conductive network in subsequent processing. Subsequently, covalent connections are established between the polydopamine layers through glutaraldehyde crosslinking treatment. The condensation reaction of aldehyde and amino groups forms a three-dimensional network structure. This crosslinking effect fixes the relative positions between graphene sheets, inhibiting graphene sheet slippage or stacking caused by mechanical stress during use, and maintaining the stability of the conductive pathway.

[0089] In some optional instances, in step (1), the mass fraction of the nitric acid solution is 65 to 70 wt%, for example, it can be 65 wt%, 65.5 wt%, 66 wt%, 66.5 wt%, 67 wt%, 67.5 wt%, 68 wt%, 68.5 wt%, 69 wt%, 69.5 wt%, or 70 wt%, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0090] In some alternative instances, the sulfuric acid solution has a mass fraction of 95 to 98 wt%, for example, 95 wt%, 95.5 wt%, 96 wt%, 96.5 wt%, 97 wt%, 97.5 wt%, or 98 wt%, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0091] In some alternative instances, the volume ratio of the nitric acid solution to the sulfuric acid solution is 1:(3-4), for example, 1:3.0, 1:3.1, 1:3.2, 1:3.3, 1:3.4, 1:3.5, 1:3.6, 1:3.7, 1:3.8, 1:3.9 or 1:4.0, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0092] In some optional instances, the ratio of the graphene powder to the mixed acid solution is 1g:(20-30)L, for example, it can be 1g:20L, 1g:21L, 1g:22L, 1g:23L, 1g:24L, 1g:25L, 1g:26L, 1g:27L, 1g:28L, 1g:29L or 1g:30L, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0093] In some optional instances, the mixing and stirring time of the graphene powder and the mixed acid solution is 2 to 3 hours, for example, 2.0 hours, 2.1 hours, 2.2 hours, 2.3 hours, 2.4 hours, 2.5 hours, 2.6 hours, 2.7 hours, 2.8 hours, 2.9 hours, or 3.0 hours, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0094] In some optional instances, the temperature at which the graphene powder is mixed and stirred with the mixed acid solution is 50 to 60°C, for example, 50°C, 51°C, 52°C, 53°C, 54°C, 55°C, 56°C, 57°C, 58°C, 59°C or 60°C, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0095] In some alternative instances, in step (2), the pH value of the Tris-HCl buffer is 8 to 9, for example, it can be 8.0, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6, 8.7, 8.8, 8.9 or 9.0, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0096] In some alternative examples, the concentration of dopamine hydrochloride in the dopamine solution is 3 to 4 mg / mL, for example, 3.0 mg / mL, 3.1 mg / mL, 3.2 mg / mL, 3.3 mg / mL, 3.4 mg / mL, 3.5 mg / mL, 3.6 mg / mL, 3.7 mg / mL, 3.8 mg / mL, 3.9 mg / mL or 4.0 mg / mL, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0097] In some alternative instances, the mass ratio of the activated graphene to dopamine hydrochloride in the dopamine solution is 1:(1 to 1.2), for example, it can be 1:1, 1:1.02, 1:1.04, 1:1.06, 1:1.08, 1:1.1, 1:1.12, 1:1.14, 1:1.16, 1:1.18 or 1:1.2, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0098] This invention specifically defines the mass ratio of activated graphene to dopamine hydrochloride in the dopamine solution as 1:(1-1.2). Within this range, dopamine hydrochloride undergoes oxidative self-polymerization under weakly alkaline conditions. Through π-π interactions, it synergistically interacts with the oxygen-containing groups on the surface of activated graphene to form a continuous polydopamine coating layer with a thickness of approximately 5-8 nm. This polydopamine coating layer not only covers the active sites at the edges of the graphene sheets to prevent excessive oxidation, but also forms stable connections with the subsequent glutaraldehyde crosslinking agent through the amino groups in the molecular chain. The appropriate addition of dopamine ensures that the polydopamine coating layer completely covers the defect areas on the graphene surface, while avoiding an excessively thick polydopamine coating layer from completely blocking the electronic transition channels between graphene sheets.

[0099] When the amount of dopamine hydrochloride added is below the lower limit defined in this invention, the concentration of dopamine monomer in the reaction system is insufficient, resulting in local coverage defects in the polydopamine coating layer. The uncovered areas on the activated graphene surface are prone to excessive interlayer crosslinking during the subsequent glutaraldehyde crosslinking stage, forming rigid connection points. This non-uniform crosslinking structure causes internal stress concentration in the graphene sheets during drying, ultimately leading to microcracks in the conductive network. Furthermore, the exposed edges of the uncoated graphene preferentially adsorb aniline monomers during the polyaniline polymerization stage, triggering localized overpolymerization and forming insulating polymer agglomerates, disrupting the continuity of the conductive pathway.

[0100] When the amount of dopamine hydrochloride added exceeds the upper limit defined in this invention, the excess dopamine monomer forms a dense coating layer with a thickness exceeding 15 nm on the graphene surface. This excessively thick polydopamine coating layer not only hinders electron transport within the graphene matrix, but its semiconductor properties also add additional resistance to the conductive network. Furthermore, free dopamine molecules not promptly removed during polymerization self-aggregate in the solution to form nanoparticles. These particles randomly adhere to the graphene surface, disrupting the uniformity of the polydopamine coating layer. Simultaneously, during subsequent hot pressing, the difference in thermal expansion coefficients between the excessively thick polydopamine coating layer and the polyaniline coating layer causes interfacial delamination, resulting in island-like detachment of the modified graphene conductive layer.

[0101] In some optional instances, the mixing and stirring time of the activated graphene and the dopamine solution is 8 to 10 hours, for example, 8.0 hours, 8.2 hours, 8.4 hours, 8.6 hours, 8.8 hours, 9.0 hours, 9.2 hours, 9.4 hours, 9.6 hours, 9.8 hours, or 10.0 hours, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0102] In some optional instances, the temperature at which the activated graphene is mixed and stirred with the dopamine solution is 25–35°C, for example, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, or 35°C, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0103] In some optional instances, in step (3), the mass fraction of glutaraldehyde in the glutaraldehyde solution is 0.5 to 1 wt%, for example, it can be 0.5 wt%, 0.55 wt%, 0.6 wt%, 0.65 wt%, 0.7 wt%, 0.75 wt%, 0.8 wt%, 0.85 wt%, 0.9 wt%, 0.95 wt%, or 1 wt%, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0104] In some alternative instances, the mass ratio of the coated graphene to the glutaraldehyde in the glutaraldehyde solution is 1:(0.5 to 0.6), for example, it can be 1:0.5, 1:0.51, 1:0.52, 1:0.53, 1:0.54, 1:0.55, 1:0.56, 1:0.57, 1:0.58, 1:0.59 or 1:0.6, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0105] In some optional instances, the mixing and stirring time of the coated graphene and the glutaraldehyde solution is 2 to 4 hours, for example, 2.0 hours, 2.2 hours, 2.4 hours, 2.6 hours, 2.8 hours, 3.0 hours, 3.2 hours, 3.4 hours, 3.6 hours, 3.8 hours, or 4.0 hours, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0106] In some optional instances, the mixing and stirring temperature of the coated graphene and the glutaraldehyde solution is 25 to 35°C, for example, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C or 35°C, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0107] As a preferred technical solution of the present invention, in step (III), the modified graphene is prepared by the following method:

[0108] The cross-linked graphene was dispersed in a sodium dodecylbenzenesulfonate solution to obtain a cross-linked graphene dispersion. Hydrochloric acid solution was added dropwise to the cross-linked graphene dispersion to adjust its pH value. Aniline monomer was added to the cross-linked graphene dispersion and mixed evenly to obtain a precursor solution. Ammonium persulfate solution was added dropwise to the precursor solution under stirring to induce monomer polymerization. After the reaction was completed, the modified graphene was obtained by centrifugation, washing with deionized water, and vacuum drying.

[0109] In some alternative examples, the sodium dodecylbenzenesulfonate solution contains 0.5 to 1 wt% sodium dodecylbenzenesulfonate, for example, 0.5 wt%, 0.55 wt%, 0.6 wt%, 0.65 wt%, 0.7 wt%, 0.75 wt%, 0.8 wt%, 0.85 wt%, 0.9 wt%, 0.95 wt%, or 1 wt%, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0110] In some optional examples, the concentration of cross-linked coated graphene in the cross-linked coated graphene dispersion is 0.3 to 0.5 mg / mL, for example, it can be 0.3 mg / mL, 0.32 mg / mL, 0.34 mg / mL, 0.36 mg / mL, 0.38 mg / mL, 0.4 mg / mL, 0.42 mg / mL, 0.44 mg / mL, 0.46 mg / mL, 0.48 mg / mL or 0.5 mg / mL, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0111] In some alternative instances, hydrochloric acid solution is added dropwise to the cross-linked graphene dispersion to adjust its pH to 1 to 2, for example, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9 or 2.0, but not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0112] In some alternative examples, the concentration of the hydrochloric acid solution is 1 to 2 mol / L, for example, it can be 1.0 mol / L, 1.1 mol / L, 1.2 mol / L, 1.3 mol / L, 1.4 mol / L, 1.5 mol / L, 1.6 mol / L, 1.7 mol / L, 1.8 mol / L, 1.9 mol / L or 2.0 mol / L, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0113] In some optional examples, the mass ratio of cross-linked coated graphene to aniline monomer in the cross-linked coated graphene dispersion is 1:(2-3), for example, it can be 1:2.0, 1:2.1, 1:2.2, 1:2.3, 1:2.4, 1:2.5, 1:2.6, 1:2.7, 1:2.8, 1:2.9 or 1:3.0, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0114] This invention specifically defines the mass ratio of cross-linked coated graphene to aniline monomer in the cross-linked coated graphene dispersion as 1:(2-3). Within this range, the aniline monomer forms a polyaniline coating layer with a thickness of approximately 10-20 nm on the surface of the cross-linked coated graphene through in-situ polymerization. The polyaniline molecular chains are tightly bonded to the graphene sheets through π-π conjugation, and their linear molecular structure extends and grows along the surface of the cross-linked coated graphene, forming a continuous conductive pathway. The appropriate addition of aniline monomer can establish a three-dimensional conductive network on the surface of the cross-linked coated graphene while avoiding excessive polyaniline covering the intrinsically conductive regions of the graphene.

[0115] When the amount of aniline monomer used is below the lower limit defined in this invention, the concentration of aniline monomer in the polymerization reaction system is insufficient, resulting in an island-like discontinuous distribution of the polyaniline coating layer on the surface of the cross-linked graphene. Some areas on the surface of the cross-linked graphene are not covered by polyaniline, and the exposed oxygen-containing groups are prone to adsorbing environmental moisture during subsequent processing, forming an insulating barrier. In addition, the sparse polyaniline network cannot effectively bridge adjacent graphene sheets, and the conductive path mainly depends on the direct contact of the cross-linked graphene. This structure is prone to local open circuits due to sheet rearrangement during hot pressing.

[0116] When the amount of aniline monomer exceeds the upper limit defined in this invention, the excess aniline monomer undergoes bulk polymerization during the polymerization process, forming polyaniline particles independent of the cross-linked graphene. These free polyaniline particles not only fail to form effective conductive connections with the cross-linked graphene, but also form insulating isolation regions in the coating. Furthermore, the overgrown polyaniline coating completely encapsulates the graphene sheets, and its thickness exceeding 30 nm significantly hinders electron transport across the cross-linked graphene substrate, reducing the intrinsic conductivity of the cross-linked graphene. Simultaneously, the excess polyaniline molecular chains generate shrinkage stress during drying and curing, leading to microcracks in the modified graphene conductive layer, severely affecting the mechanical properties of the textile fabric.

[0117] In some optional examples, the mixing time of the cross-linked graphene dispersion with the aniline monomer is 10 to 15 min, for example, 10 min, 10.5 min, 11 min, 11.5 min, 12 min, 12.5 min, 13 min, 13.5 min, 14 min, 14.5 min or 15 min, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0118] In some alternative examples, the mass fraction of the ammonium persulfate solution is 10 to 12 wt%, for example, 10 wt%, 10.2 wt%, 10.4 wt%, 10.6 wt%, 10.8 wt%, 11 wt%, 11.2 wt%, 11.4 wt%, 11.6 wt%, 11.8 wt%, or 12 wt%, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0119] In some alternative examples, the dropping rate of the ammonium persulfate solution is 1 to 2 mL / min, for example, 1.0 mL / min, 1.1 mL / min, 1.2 mL / min, 1.3 mL / min, 1.4 mL / min, 1.5 mL / min, 1.6 mL / min, 1.7 mL / min, 1.8 mL / min, 1.9 mL / min or 2.0 mL / min, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0120] In some alternative examples, the molar ratio of the aniline monomer to the ammonium persulfate in the ammonium persulfate solution is 1:(1 to 1.1), for example, it can be 1:1, 1:1.01, 1:1.02, 1:1.03, 1:1.04, 1:1.05, 1:1.06, 1:1.07, 1:1.08, 1:1.09 or 1:1.1, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0121] In some optional instances, after all the ammonium persulfate solution has been added dropwise, the mixture is stirred for 10 to 15 hours, for example, 10 hours, 10.5 hours, 11 hours, 11.5 hours, 12 hours, 12.5 hours, 13 hours, 13.5 hours, 14 hours, 14.5 hours, or 15 hours, but it is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0122] As a preferred technical solution of the present invention, in step (IV), the composite solvent is composed of sodium dodecylbenzenesulfonate, polyvinylpyrrolidone, anhydrous ethanol and deionized water.

[0123] In some alternative examples, the mass fraction of sodium dodecylbenzenesulfonate in the composite solvent is 0.8 to 1 wt%, for example, it can be 0.8 wt%, 0.82 wt%, 0.84 wt%, 0.86 wt%, 0.88 wt%, 0.9 wt%, 0.92 wt%, 0.94 wt%, 0.96 wt%, 0.98 wt%, or 1 wt%, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0124] In some alternative examples, the mass fraction of polyvinylpyrrolidone in the composite solvent is 0.3 to 0.5 wt%, for example, it may be 0.3 wt%, 0.32 wt%, 0.34 wt%, 0.36 wt%, 0.38 wt%, 0.4 wt%, 0.42 wt%, 0.44 wt%, 0.46 wt%, 0.48 wt%, or 0.5 wt%, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0125] In some optional instances, the volume ratio of anhydrous ethanol to deionized water in the composite solvent is 1:(2-3), for example, it can be 1:2.0, 1:2.1, 1:2.2, 1:2.3, 1:2.4, 1:2.5, 1:2.6, 1:2.7, 1:2.8, 1:2.9 or 1:3.0, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0126] In some alternative examples, the concentration of the modified graphene in the modified graphene dispersion is 2 to 3 mg / mL, for example, 2.0 mg / mL, 2.1 mg / mL, 2.2 mg / mL, 2.3 mg / mL, 2.4 mg / mL, 2.5 mg / mL, 2.6 mg / mL, 2.7 mg / mL, 2.8 mg / mL, 2.9 mg / mL or 3.0 mg / mL, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0127] In some optional examples, the high-speed stirring speed of the modified graphene and the composite solvent is 2000 to 3000 rpm, for example, 2000 rpm, 2100 rpm, 2200 rpm, 2300 rpm, 2400 rpm, 2500 rpm, 2600 rpm, 2700 rpm, 2800 rpm, 2900 rpm or 3000 rpm, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0128] In some optional examples, the high-speed stirring time of the modified graphene and the composite solvent is 10 to 15 min, for example, 10 min, 10.5 min, 11 min, 11.5 min, 12 min, 12.5 min, 13 min, 13.5 min, 14 min, 14.5 min or 15 min, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0129] In some optional instances, the modified graphene dispersion is coated by reciprocating spraying.

[0130] In some alternative examples, the spraying pressure of the modified graphene dispersion is 0.3 to 0.4 MPa, for example, 0.3 MPa, 0.31 MPa, 0.32 MPa, 0.33 MPa, 0.34 MPa, 0.35 MPa, 0.36 MPa, 0.37 MPa, 0.38 MPa, 0.39 MPa or 0.4 MPa, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0131] In some optional examples, the spraying distance of the modified graphene dispersion is 10 to 20 cm, for example, it can be 10 cm, 11 cm, 12 cm, 13 cm, 14 cm, 15 cm, 16 cm, 17 cm, 18 cm, 19 cm or 20 cm, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0132] In some optional instances, the modified graphene dispersion is sprayed 3 to 5 times, for example, 3, 4 or 5 times, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0133] In some alternative instances, the drying temperature is 50–60°C, for example, 50°C, 51°C, 52°C, 53°C, 54°C, 55°C, 56°C, 57°C, 58°C, 59°C, or 60°C, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0134] In some alternative instances, the drying time is 5 to 8 minutes, for example, 5.0 minutes, 5.5 minutes, 6.0 minutes, 6.5 minutes, 7.0 minutes, 7.5 minutes or 8.0 minutes, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0135] In some alternative instances, the curing temperature is 90 to 100°C, for example, 90°C, 91°C, 92°C, 93°C, 94°C, 95°C, 96°C, 97°C, 98°C, 99°C, or 100°C, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0136] In some optional instances, the curing time is 3 to 5 minutes, for example, 3.0 minutes, 3.2 minutes, 3.4 minutes, 3.6 minutes, 3.8 minutes, 4.0 minutes, 4.2 minutes, 4.4 minutes, 4.6 minutes, 4.8 minutes, or 5.0 minutes, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0137] In some alternative instances, the hot pressing temperature is 80 to 90°C, for example, 80°C, 81°C, 82°C, 83°C, 84°C, 85°C, 86°C, 87°C, 88°C, 89°C, or 90°C, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0138] In some optional instances, the hot pressing time is 10 to 20 seconds, for example, 10 seconds, 11 seconds, 12 seconds, 13 seconds, 14 seconds, 15 seconds, 16 seconds, 17 seconds, 18 seconds, 19 seconds, or 20 seconds, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0139] In some alternative instances, the hot pressing pressure is 6 to 8 MPa, for example, 6.0 MPa, 6.2 MPa, 6.4 MPa, 6.6 MPa, 6.8 MPa, 7.0 MPa, 7.2 MPa, 7.4 MPa, 7.6 MPa, 7.8 MPa or 8.0 MPa, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0140] In some optional instances, the thickness of the modified graphene conductive layer is 10–15 μm, for example, 10 μm, 10.5 μm, 11 μm, 11.5 μm, 12 μm, 12.5 μm, 13 μm, 13.5 μm, 14 μm, 14.5 μm or 15 μm, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0141] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0142] The conductive textile fabric provided by this invention achieves synergistic optimization of high conductivity, environmental resistance, and mechanical flexibility through a multi-layer composite structure consisting of a composite polyurethane base film, a functionalized adhesive layer, and a modified graphene conductive layer. The stearic acid-modified nano-titanium dioxide-reinforced composite polyurethane base film forms a microporous structure during blow molding, balancing breathability and bending resistance, thus solving the problem of stiffness and easy breakage in traditional metal fiber conductive fabrics. The three-dimensional adhesive network constructed from carboxylated nanowires and epoxy resin strengthens the interfacial bonding strength between the composite polyurethane base film and the modified graphene conductive layer through both chemical bonding and mechanical interlocking, effectively resisting interlayer delamination caused by repeated bending and washing. The graphene conductive layer, modified by acid activation, polydopamine coating, and polyaniline polymerization, forms a "core-shell-crosslinked" composite structure, retaining the intrinsic high conductivity of graphene while suppressing sheet slippage through flexible polymer coating, achieving a stable conductive network under dynamic stress. The conductive textile fabric obtained by this invention retains the soft touch of natural fabrics while possessing excellent conductivity and mechanical properties. It can be widely used in smart wearable devices, medical sensing clothing, and electromagnetic shielding materials, and has significant industrialization value. Attached Figure Description

[0143] Figure 1 This is a schematic diagram of the structure of the conductive textile fabrics prepared in Examples 1-15 of the present invention;

[0144] Among them, 1-composite polyurethane base film; 2-adhesive layer; 3-modified graphene conductive layer. Detailed Implementation

[0145] The technical solution of the present invention will be described in detail below with reference to specific embodiments and accompanying drawings. The embodiments described herein are specific implementations of the present invention, used to illustrate the concept of the present invention; these descriptions are explanatory and exemplary, and should not be construed as limiting the implementation of the present invention or the scope of protection of the present invention. In addition to the embodiments described herein, those skilled in the art can also adopt other obvious technical solutions based on the content disclosed in the claims and specification of this application. These technical solutions include those that make any obvious substitutions and modifications to the embodiments described herein. Epoxy resin emulsion: solid content 40%, model K-051, Shenyang Baichen Chemical Technology Co., Ltd. Polyvinylpyrrolidone: model XDD6, Wuhan Xindadi Environmental Protection Materials Co., Ltd. Polyetheramine: Polyetheramine D-2000, Hubei Jusheng Technology Co., Ltd.

[0146] Example 1

[0147] This embodiment provides a method for preparing a conductive textile fabric, the preparation method specifically including the following steps:

[0148] (1) Stearic acid was dissolved in anhydrous ethanol and mixed and stirred at 60°C for 50 min to obtain a stearic acid solution with a mass fraction of 3.0 wt% for stearic acid. Nano-titanium dioxide and stearic acid solution were mixed and ball-milled with a mass ratio of 1:0.15 between nano-titanium dioxide and stearic acid in the stearic acid solution. The ball milling speed was 250 rpm and the ball milling time was 4 h. The ball-to-material ratio was 1:6. After ball milling, the ball milling product was filtered. The filter cake was washed with deionized water until neutral and then vacuum-dried at 60°C for 10 h to obtain modified nano-titanium dioxide.

[0149] Polyurethane granules (thermoplastic polyurethane, 85A, purchased from Dongguan Bailing New Materials Co., Ltd.), modified nano titanium dioxide, and calcium stearate were mixed at a mass ratio of 100:8:1.5 and stirred at 130℃ for 50 min to obtain a mixture. The mixture was then fed into a screw extruder for melt extrusion. The temperature of the first zone of the screw extruder was 165℃, the temperature of the second zone was 180℃, and the temperature of the third zone was 195℃. The screw speed was 35 rpm. After screw extrusion, the mixture was granulated to obtain a composite masterbatch. The composite masterbatch was then blow-molded into a film with a blow-up ratio of 2.5:1 to obtain a composite polyurethane base film with a thickness of 30 μm.

[0150] (2) A 6 wt% hydrogen peroxide solution and a 7 wt% sodium hydroxide solution were mixed, with a volume ratio of 1:1.3. After mixing evenly, a modified solution was obtained. Silicon carbide nanowires (JK-R0746, purchased from Shanghai Jingkang Bioengineering Co., Ltd.) were added to the modified solution, with a mass ratio of 1:30 between the silicon carbide nanowires and the modified solution. The mixture was ultrasonically dispersed for 50 min at an ultrasonic power of 300 W. Then, it was transferred to a reactor for high-temperature reaction at a temperature of 120 °C for 6 h. After the reaction was completed, the reaction product was filtered. The filter cake was washed with deionized water until neutral and then vacuum dried at 60 °C for 10 h to obtain carboxylated nanowires.

[0151] Epoxy resin emulsion (40% solids content, model K-051, purchased from Shenyang Baichen Chemical Technology Co., Ltd.), polyvinylpyrrolidone (model XDD6, purchased from Wuhan Xindadi Environmental Protection Materials Co., Ltd.), and polyetheramine (polyetheramine D-2000, purchased from Hubei Jusheng Technology Co., Ltd.) were added to deionized water. The mass ratio of epoxy resin emulsion, polyvinylpyrrolidone, polyetheramine, and deionized water was 15:1.5:3:80. The mixture was stirred at 40°C for 40 min to obtain the adhesive base liquid. Carboxylated nanowires were then added to the adhesive base liquid and ultrasonically dispersed to obtain a composite adhesive. The mass fraction of carboxylated nanowires in the composite adhesive was 3 wt%. The composite adhesive was coated onto the surface of the composite polyurethane base film 1 at a coating speed of 10 m / min. After coating, the film was dried at 70°C for 25 min and then cured at 90°C for 3 h to form an adhesive layer 2 with a thickness of 8 μm on the surface of the composite polyurethane base film 1.

[0152] (3) Mix a 65wt% nitric acid solution and a 95wt% sulfuric acid solution with a volume ratio of 1:3. After mixing evenly, a mixed acid solution is obtained. Graphene powder is dispersed in the mixed acid solution with a ratio of 1g:20L. The mixture is stirred at 50℃ for 3h to allow the reaction to occur. After the reaction is completed, the mixture is centrifuged. The precipitate after centrifugation is washed with 1mol / L sodium hydroxide solution until neutral. Then, it is vacuum dried at 60℃ for 10h to obtain activated graphene.

[0153] Dopamine hydrochloride was dissolved in Tris-HCl buffer solution with a pH of 8 to obtain a dopamine solution with a concentration of 3 mg / mL. Activated graphene was dispersed in the dopamine solution at a mass ratio of 1:1 to the dopamine hydrochloride in the solution. The mixture was stirred at 25 °C for 10 h to induce polymerization. After the reaction was completed, the mixture was centrifuged and the precipitate was washed with deionized water until neutral. The precipitate was then vacuum dried at 60 °C for 10 h to obtain graphene coated with a polydopamine layer.

[0154] Glutaraldehyde was added to a Tris-HCl buffer solution with a pH of 8 to obtain a glutaraldehyde solution with a mass fraction of 0.5 wt%. Graphene-coated graphene was added to the glutaraldehyde solution at a mass ratio of 1:0.5. The mixture was stirred at 25 °C for 4 h to induce a cross-linking reaction. After the reaction, the mixture was centrifuged and the precipitate was washed with deionized water until neutral. The precipitate was then vacuum dried at 60 °C for 10 h to obtain cross-linked coated graphene.

[0155] Cross-linked graphene was dispersed in a 0.5 wt% sodium dodecylbenzenesulfonate solution to obtain a cross-linked graphene dispersion with a concentration of 0.3 mg / mL. A 1 mol / L hydrochloric acid solution was added dropwise to adjust the pH to 2. Aniline monomer was then added to the cross-linked graphene dispersion, with a mass ratio of cross-linked graphene to aniline monomer of 1:2. The mixture was stirred... After stirring for 10 min, a precursor solution was obtained. Under stirring conditions, a 10 wt% ammonium persulfate solution was added dropwise to the precursor solution at a rate of 1 mL / min. The molar ratio of aniline monomer to ammonium persulfate in the ammonium persulfate solution was 1:1. After all the ammonium persulfate solution was added, the mixture was stirred for 10 h to allow the monomer polymerization reaction to occur. After the reaction was completed, the mixture was centrifuged and the precipitate was washed with deionized water until neutral. Then, it was vacuum dried at 60 °C for 10 h to obtain modified graphene.

[0156] (4) Sodium dodecylbenzenesulfonate, polyvinylpyrrolidone (model XDD6, purchased from Wuhan Xindadi Environmental Protection Materials Co., Ltd.), anhydrous ethanol and deionized water were mixed evenly to obtain a composite solvent. The mass fraction of sodium dodecylbenzenesulfonate in the composite solvent was 0.8wt%, the mass fraction of polyvinylpyrrolidone was 0.3wt%, and the volume ratio of anhydrous ethanol and deionized water was 1:2. Modified graphene was dispersed in the composite solvent and stirred at 2000 rpm for 15 min to obtain a modified graphene dispersion. The concentration of modified graphene in the modified graphene dispersion was 2 mg / mL.

[0157] The modified graphene dispersion was repeatedly sprayed onto the surface of the adhesive layer 2. The spraying pressure was 0.3 MPa, the spraying distance was 10 cm, and the spraying was repeated 3 times. After spraying, it was dried at 50℃ for 8 min, then cured at 90℃ for 5 min, and finally hot-pressed at 80℃ and 6 MPa for 20 s to form a modified graphene conductive layer 3 with a thickness of 10 μm on the surface of the adhesive layer 2, resulting in the desired product. Figure 1 The conductive textile fabric shown.

[0158] Example 2

[0159] This embodiment provides a method for preparing a conductive textile fabric, the preparation method specifically including the following steps:

[0160] (1) Stearic acid was dissolved in anhydrous ethanol and mixed and stirred at 62°C for 48 min to obtain a stearic acid solution with a mass fraction of 3.2 wt% for stearic acid. Nano-titanium dioxide and stearic acid solution were mixed and ball-milled with a mass ratio of 1:0.18 between nano-titanium dioxide and stearic acid in the stearic acid solution. The ball milling speed was 280 rpm and the ball milling time was 3.8 h. The ball-to-material ratio was 1:6.5. After ball milling, the ball milling product was filtered and the filter cake was washed with deionized water until neutral. Then it was vacuum dried at 62°C for 9.5 h to obtain modified nano-titanium dioxide.

[0161] Polyurethane particles, modified nano-titanium dioxide, and calcium stearate were mixed at a mass ratio of 100:8.5:1.8 and stirred at 132°C for 48 min to obtain a mixture. The mixture was then fed into a screw extruder for melt extrusion. The temperature of the first zone of the screw extruder was 168°C, the temperature of the second zone was 182°C, and the temperature of the third zone was 198°C. The screw speed was 38 rpm. After screw extrusion, the mixture was granulated to obtain a composite masterbatch. The composite masterbatch was then blow-molded into a film with a blow-up ratio of 2.8:1 to obtain a composite polyurethane base film 1 with a thickness of 32 μm.

[0162] (2) A 6.5 wt% hydrogen peroxide solution and a 7.5 wt% sodium hydroxide solution were mixed, with a volume ratio of 1:1.35. After mixing evenly, a modified solution was obtained. Silicon carbide nanowires were added to the modified solution, with a mass ratio of 1:32 between the silicon carbide nanowires and the modified solution. The mixture was ultrasonically dispersed at 320 W for 48 min. Then, it was transferred to a reactor for high-temperature reaction at 122 °C for 5.8 h. After the reaction was completed, the reaction product was filtered. The filter cake was washed with deionized water until neutral. Then, it was vacuum dried at 62 °C for 9.5 h to obtain carboxylated nanowires.

[0163] Epoxy resin emulsion, polyvinylpyrrolidone, and polyetheramine were added to deionized water in a mass ratio of 15.5:1.8:3.5:82. The mixture was stirred at 42°C for 38 min to obtain a binder base liquid. Carboxylated nanowires were then added to the binder base liquid and ultrasonically dispersed to obtain a composite binder. The mass fraction of carboxylated nanowires in the composite binder was 3.2 wt%. The composite binder was coated onto the surface of a composite polyurethane base film 1 at a coating speed of 10.5 m / min. After coating, the film was dried at 72°C for 22 min and then cured at 92°C for 2.8 h to form an adhesive layer 2 with a thickness of 8.5 μm on the surface of the composite polyurethane base film 1.

[0164] (3) A 66 wt% nitric acid solution and a 96 wt% sulfuric acid solution were mixed, with a volume ratio of 1:3.2. After mixing evenly, a mixed acid solution was obtained. Graphene powder was dispersed in the mixed acid solution, with a ratio of 1 g to 22 L. The mixture was stirred at 52 °C for 2.8 h to allow the reaction to occur. After the reaction was completed, the mixture was centrifuged. The precipitate was washed with 1 mol / L sodium hydroxide solution until neutral. Then, it was vacuum dried at 62 °C for 9.5 h to obtain activated graphene.

[0165] Dopamine hydrochloride was dissolved in Tris-HCl buffer solution with a pH of 8.2 to obtain a dopamine solution with a concentration of 3.2 mg / mL. Activated graphene was dispersed in the dopamine solution at a mass ratio of 1:1.05 to the dopamine hydrochloride in the solution. The mixture was stirred at 28 °C for 9.5 h to induce polymerization. After the reaction was completed, the mixture was centrifuged and the precipitate was washed with deionized water until neutral. The precipitate was then vacuum dried at 62 °C for 9.5 h to obtain graphene coated with a polydopamine layer.

[0166] Glutaraldehyde was added to a Tris-HCl buffer solution with a pH of 8.2 to obtain a glutaraldehyde solution with a mass fraction of 0.6 wt%. Graphene-coated graphene was added to the glutaraldehyde solution at a mass ratio of 1:0.52. The mixture was stirred at 28 °C for 3.5 h to induce a cross-linking reaction. After the reaction, the mixture was centrifuged and the precipitate was washed with deionized water until neutral. The precipitate was then vacuum dried at 62 °C for 9.5 h to obtain cross-linked graphene.

[0167] Cross-linked graphene was dispersed in a 0.6 wt% sodium dodecylbenzenesulfonate solution to obtain a cross-linked graphene dispersion with a concentration of 0.35 mg / mL. A 1.2 mol / L hydrochloric acid solution was added dropwise to adjust the pH to 1.8. Aniline monomer was then added to the cross-linked graphene dispersion, with a mass ratio of cross-linked graphene to aniline monomer of 1:2.2. The mixture was stirred. After 11 min, a precursor solution was obtained. Under stirring conditions, a 10.5 wt% ammonium persulfate solution was added dropwise to the precursor solution at a rate of 1.2 mL / min. The molar ratio of aniline monomer to ammonium persulfate in the ammonium persulfate solution was 1:1.02. After all the ammonium persulfate solution was added, the mixture was stirred for 11 h to allow the monomer polymerization reaction to occur. After the reaction was completed, the mixture was centrifuged and the precipitate was washed with deionized water until neutral. Then, it was vacuum dried at 62 °C for 9.5 h to obtain modified graphene.

[0168] (4) Sodium dodecylbenzenesulfonate, polyvinylpyrrolidone, anhydrous ethanol and deionized water were mixed evenly to obtain a composite solvent. The mass fraction of sodium dodecylbenzenesulfonate in the composite solvent was 0.85 wt%, the mass fraction of polyvinylpyrrolidone was 0.35 wt%, and the volume ratio of anhydrous ethanol and deionized water was 1:2.2. Modified graphene was dispersed in the composite solvent and stirred at 2200 rpm for 13 min to obtain a modified graphene dispersion. The concentration of modified graphene in the modified graphene dispersion was 2.2 mg / mL.

[0169] The modified graphene dispersion was repeatedly sprayed onto the surface of the adhesive layer 2. The spraying pressure was 0.32 MPa, the spraying distance was 12 cm, and the spraying was repeated 3 times. After spraying, it was dried at 52℃ for 7 min, then cured at 92℃ for 4.5 min, and finally hot-pressed at 82℃ and 6.5 MPa for 18 s to form a modified graphene conductive layer 3 with a thickness of 11 μm on the surface of the adhesive layer 2, resulting in the desired product. Figure 1 The conductive textile fabric shown.

[0170] Example 3

[0171] This embodiment provides a method for preparing a conductive textile fabric, the preparation method specifically including the following steps:

[0172] (1) Stearic acid was dissolved in anhydrous ethanol and mixed and stirred at 65°C for 45 min to obtain a stearic acid solution with a mass fraction of 3.5 wt% for stearic acid. Nano-titanium dioxide and stearic acid solution were mixed and ball-milled with a mass ratio of 1:0.2 for nano-titanium dioxide to stearic acid in stearic acid solution. The ball milling speed was 300 rpm and the ball milling time was 3.5 h. The ball-to-material ratio was 1:7. After ball milling, the ball milling product was filtered and the filter cake was washed with deionized water until neutral. Then it was vacuum dried at 65°C for 9 h to obtain modified nano-titanium dioxide.

[0173] Polyurethane particles, modified nano-titanium dioxide, and zinc stearate were mixed in a mass ratio of 100:9:2 and stirred at 135°C for 45 min to obtain a mixture. The mixture was then fed into a screw extruder for melt extrusion. The temperature of the first zone of the screw extruder was 170°C, the temperature of the second zone was 185°C, and the temperature of the third zone was 200°C. The screw speed was 40 rpm. After screw extrusion, the mixture was granulated to obtain a composite masterbatch. The composite masterbatch was then blow-molded into a film with a blow-up ratio of 3:1 to obtain a composite polyurethane base film 1 with a thickness of 35 μm.

[0174] (2) A 7 wt% hydrogen peroxide solution and an 8 wt% sodium hydroxide solution were mixed, with a volume ratio of 1:1.4. After mixing evenly, a modified solution was obtained. Silicon carbide nanowires were added to the modified solution, with a mass ratio of 1:35 between the silicon carbide nanowires and the modified solution. The mixture was ultrasonically dispersed at 350 W for 45 min. Then, it was transferred to a reactor for high-temperature reaction at 125 °C for 5.5 h. After the reaction was completed, the reaction product was filtered. The filter cake was washed with deionized water until neutral. Then, it was vacuum dried at 65 °C for 9 h to obtain carboxylated nanowires.

[0175] Epoxy resin emulsion, polyvinylpyrrolidone, and polyetheramine were added to deionized water in a mass ratio of 16:2:4:85. The mixture was stirred at 45°C for 35 min to obtain a binder base liquid. Carboxylated nanowires were then added to the binder base liquid and ultrasonically dispersed to obtain a composite binder. The mass fraction of carboxylated nanowires in the composite binder was 3.5 wt%. The composite binder was coated onto the surface of a composite polyurethane base film 1 at a coating speed of 11 m / min. After coating, the film was dried at 75°C for 20 min and then cured at 95°C for 2.5 h to form a 9 μm thick adhesive layer 2 on the surface of the composite polyurethane base film 1.

[0176] (3) Mix a 67wt% nitric acid solution and a 96wt% sulfuric acid solution with a volume ratio of 1:3.5. After mixing evenly, a mixed acid solution is obtained. Graphene powder is dispersed in the mixed acid solution with a ratio of 1g:25L. The mixture is stirred at 55℃ for 2.5h to allow the reaction to occur. After the reaction is completed, the mixture is centrifuged and the precipitate is washed with 1mol / L sodium hydroxide solution until neutral. Then, it is vacuum dried at 65℃ for 9h to obtain activated graphene.

[0177] Dopamine hydrochloride was dissolved in Tris-HCl buffer solution with a pH of 8.5 to obtain a dopamine solution with a concentration of 3.5 mg / mL. Activated graphene was dispersed in the dopamine solution at a mass ratio of 1:1.1 to the activated graphene. The mixture was stirred at 30 °C for 9 h to induce polymerization. After the reaction, the mixture was centrifuged and the precipitate was washed with deionized water until neutral. The precipitate was then vacuum dried at 65 °C for 9 h to obtain graphene coated with a polydopamine layer.

[0178] Glutaraldehyde was added to a Tris-HCl buffer solution with a pH of 8.5 to obtain a glutaraldehyde solution with a mass fraction of 0.7 wt%. Graphene-coated graphene was added to the glutaraldehyde solution at a mass ratio of 1:0.55. The mixture was stirred at 30 °C for 3 h to induce a cross-linking reaction. After the reaction, the mixture was centrifuged and the precipitate was washed with deionized water until neutral. The precipitate was then vacuum dried at 65 °C for 9 h to obtain cross-linked coated graphene.

[0179] Cross-linked graphene was dispersed in a 0.7 wt% sodium dodecylbenzenesulfonate solution to obtain a cross-linked graphene dispersion with a concentration of 0.4 mg / mL. A 1.5 mol / L hydrochloric acid solution was added dropwise to adjust the pH to 1.5. Aniline monomer was then added to the cross-linked graphene dispersion, with a mass ratio of cross-linked graphene to aniline monomer of 1:2.5. The mixture was then... After stirring for 12 min, a precursor solution was obtained. Under stirring conditions, an 11 wt% ammonium persulfate solution was added dropwise to the precursor solution at a rate of 1.5 mL / min. The molar ratio of aniline monomer to ammonium persulfate in the ammonium persulfate solution was 1:1.05. After all the ammonium persulfate solution was added, the mixture was stirred for 12 h to allow the monomer polymerization reaction to occur. After the reaction was completed, the mixture was centrifuged and the precipitate was washed with deionized water until neutral. Then, it was vacuum dried at 65 °C for 9 h to obtain modified graphene.

[0180] (4) Sodium dodecylbenzenesulfonate, polyvinylpyrrolidone, anhydrous ethanol and deionized water were mixed evenly to obtain a composite solvent. The mass fraction of sodium dodecylbenzenesulfonate in the composite solvent was 0.9 wt%, the mass fraction of polyvinylpyrrolidone was 0.4 wt%, and the volume ratio of anhydrous ethanol and deionized water was 1:2.5. Modified graphene was dispersed in the composite solvent and stirred at 2500 rpm for 12 min to obtain a modified graphene dispersion. The concentration of modified graphene in the modified graphene dispersion was 2.5 mg / mL.

[0181] The modified graphene dispersion was repeatedly sprayed onto the surface of the adhesive layer 2. The spraying pressure was 0.35 MPa, the spraying distance was 15 cm, and the spraying was repeated 4 times. After spraying, it was dried at 55℃ for 6 min, then cured at 95℃ for 4 min, and finally hot-pressed at 85℃ and 7 MPa for 15 s to form a modified graphene conductive layer 3 with a thickness of 12 μm on the surface of the adhesive layer 2, resulting in the desired product. Figure 1 The conductive textile fabric shown.

[0182] Example 4

[0183] This embodiment provides a method for preparing a conductive textile fabric, the preparation method specifically including the following steps:

[0184] (1) Stearic acid was dissolved in anhydrous ethanol and mixed and stirred at 68°C for 42 min to obtain a stearic acid solution with a mass fraction of 3.8 wt% for stearic acid. Nano-titanium dioxide and stearic acid solution were mixed and ball-milled with a mass ratio of 1:0.22 for nano-titanium dioxide to stearic acid in stearic acid solution. The ball milling speed was 320 rpm and the ball milling time was 3.2 h. The ball-to-material ratio was 1:7.5. After ball milling, the ball milling product was filtered and the filter cake was washed with deionized water until neutral. Then it was vacuum dried at 68°C for 8.5 h to obtain modified nano-titanium dioxide.

[0185] Polyurethane particles, modified nano-titanium dioxide, and zinc stearate were mixed at a mass ratio of 100:9.5:2.2 and stirred at 138°C for 42 min to obtain a mixture. The mixture was then fed into a screw extruder for melt extrusion. The temperature of the first zone of the screw extruder was 172°C, the temperature of the second zone was 188°C, and the temperature of the third zone was 202°C. The screw speed was 42 rpm. After screw extrusion, the mixture was granulated to obtain a composite masterbatch. The composite masterbatch was then blow-molded into a film with a blow-up ratio of 3.2:1 to obtain a composite polyurethane base film 1 with a thickness of 38 μm.

[0186] (2) A 7.5 wt% hydrogen peroxide solution and an 8.5 wt% sodium hydroxide solution were mixed, with a volume ratio of 1:1.45. After mixing evenly, a modified solution was obtained. Silicon carbide nanowires were added to the modified solution, with a mass ratio of 1:38 between the silicon carbide nanowires and the modified solution. The mixture was ultrasonically dispersed at 380 W for 42 min. Then, it was transferred to a reactor for high-temperature reaction at 128 °C for 5.2 h. After the reaction was completed, the reaction product was filtered. The filter cake was washed with deionized water until neutral. Then, it was vacuum dried at 68 °C for 8.5 h to obtain carboxylated nanowires.

[0187] Epoxy resin emulsion, polyvinylpyrrolidone, and polyetheramine were added to deionized water in a mass ratio of 16.5:2.2:4.5:88. The mixture was stirred at 48°C for 32 min to obtain a binder base liquid. Carboxylated nanowires were then added to the binder base liquid and ultrasonically dispersed to obtain a composite binder. The mass fraction of carboxylated nanowires in the composite binder was 3.8 wt%. The composite binder was coated onto the surface of a composite polyurethane base film 1 at a coating speed of 11.5 m / min. After coating, the film was dried at 78°C for 18 min and then cured at 98°C for 2.2 h to form a 9.5 μm thick adhesive layer 2 on the surface of the composite polyurethane base film 1.

[0188] (3) A nitric acid solution with a mass fraction of 68 wt% and a sulfuric acid solution with a mass fraction of 97 wt% were mixed, with a volume ratio of 1:3.8. After mixing evenly, a mixed acid solution was obtained. Graphene powder was dispersed in the mixed acid solution, with a ratio of 1 g to 28 L of graphene powder to mixed acid solution. The mixture was stirred at 58 °C for 2.2 h to allow the reaction to occur. After the reaction was completed, the mixture was centrifuged. The precipitate after centrifugation was washed with 1 mol / L sodium hydroxide solution until neutral. Then, it was vacuum dried at 68 °C for 8.5 h to obtain activated graphene.

[0189] Dopamine hydrochloride was dissolved in Tris-HCl buffer solution with a pH of 8.8 to obtain a dopamine solution with a concentration of 3.8 mg / mL. Activated graphene was dispersed in the dopamine solution at a mass ratio of 1:1.15 to the dopamine hydrochloride in the solution. The mixture was stirred at 32 °C for 8.5 h to induce polymerization. After the reaction was completed, the mixture was centrifuged and the precipitate was washed with deionized water until neutral. The precipitate was then vacuum dried at 68 °C for 8.5 h to obtain graphene coated with a polydopamine layer.

[0190] Glutaraldehyde was added to a Tris-HCl buffer solution with a pH of 8.8 to obtain a glutaraldehyde solution with a mass fraction of 0.8 wt%. Graphene-coated graphene was added to the glutaraldehyde solution at a mass ratio of 1:0.58. The mixture was stirred at 32°C for 2.5 h to induce a cross-linking reaction. After the reaction, the mixture was centrifuged and the precipitate was washed with deionized water until neutral. The precipitate was then vacuum dried at 68°C for 8.5 h to obtain cross-linked graphene.

[0191] Cross-linked graphene was dispersed in a 0.8 wt% sodium dodecylbenzenesulfonate solution to obtain a cross-linked graphene dispersion with a concentration of 0.45 mg / mL. A 1.8 mol / L hydrochloric acid solution was added dropwise to adjust the pH to 1.2. Aniline monomer was then added to the cross-linked graphene dispersion, with a mass ratio of cross-linked graphene to aniline monomer of 1:2.8. The mixture was stirred. After 13 min, a precursor solution was obtained. Under stirring conditions, an 11.5 wt% ammonium persulfate solution was added dropwise to the precursor solution at a rate of 1.8 mL / min. The molar ratio of aniline monomer to ammonium persulfate in the ammonium persulfate solution was 1:1.08. After all the ammonium persulfate solution was added, the mixture was stirred for 13 h to allow the monomer polymerization reaction to occur. After the reaction was completed, the mixture was centrifuged and the precipitate was washed with deionized water until neutral. Then, it was vacuum dried at 68 °C for 8.5 h to obtain modified graphene.

[0192] (4) Sodium dodecylbenzenesulfonate, polyvinylpyrrolidone, anhydrous ethanol and deionized water were mixed evenly to obtain a composite solvent. The mass fraction of sodium dodecylbenzenesulfonate in the composite solvent was 0.95 wt%, the mass fraction of polyvinylpyrrolidone was 0.45 wt%, and the volume ratio of anhydrous ethanol and deionized water was 1:2.8. Modified graphene was dispersed in the composite solvent and stirred at 2800 rpm for 11 min to obtain a modified graphene dispersion. The concentration of modified graphene in the modified graphene dispersion was 2.8 mg / mL.

[0193] The modified graphene dispersion was repeatedly sprayed onto the surface of the adhesive layer 2. The spraying pressure was 0.38 MPa, the spraying distance was 18 cm, and the spraying was repeated 4 times. After spraying, it was dried at 58℃ for 6 min, then cured at 98℃ for 3.5 min, and finally hot-pressed at 88℃ and 7.5 MPa for 12 s to form a modified graphene conductive layer 3 with a thickness of 13 μm on the surface of the adhesive layer 2, resulting in the desired product. Figure 1 The conductive textile fabric shown.

[0194] Example 5

[0195] This embodiment provides a method for preparing a conductive textile fabric, the preparation method specifically including the following steps:

[0196] (1) Stearic acid was dissolved in anhydrous ethanol and mixed and stirred at 70°C for 40 min to obtain a stearic acid solution with a mass fraction of 4 wt% for stearic acid. Nano-titanium dioxide and stearic acid solution were mixed and ball-milled with a mass ratio of 1:0.25 between nano-titanium dioxide and stearic acid in the stearic acid solution. The ball milling speed was 350 rpm and the ball milling time was 3 h. The ball-to-material ratio was 1:8. After ball milling, the ball milling product was filtered. The filter cake was washed with deionized water until neutral and then vacuum dried at 70°C for 8 h to obtain modified nano-titanium dioxide.

[0197] Polyurethane particles, modified nano-titanium dioxide, and zinc stearate were mixed at a mass ratio of 100:10:2.5 and stirred at 140℃ for 40 min to obtain a mixture. The mixture was then fed into a screw extruder for melt extrusion. The temperature of the first zone of the screw extruder was 175℃, the temperature of the second zone was 190℃, and the temperature of the third zone was 205℃. The screw speed was 45 rpm. After screw extrusion, the mixture was granulated to obtain a composite masterbatch. The composite masterbatch was then blow-molded into a film with a blow-up ratio of 3.5:1 to obtain a composite polyurethane base film 1 with a thickness of 40 μm.

[0198] (2) Mix 8 wt% hydrogen peroxide solution and 9 wt% sodium hydroxide solution, with a volume ratio of 1:1.5. After mixing evenly, a modified solution is obtained. Add silicon carbide nanowires to the modified solution, with a mass ratio of 1:40 between silicon carbide nanowires and the modified solution. Disperse the mixture ultrasonically at 400 W for 40 min. Then transfer it to a reactor for high-temperature reaction at 130 °C for 5 h. After the reaction, filter the product and wash the filter cake with deionized water until neutral. Then vacuum dry it at 70 °C for 8 h to obtain carboxylated nanowires.

[0199] Epoxy resin emulsion, polyvinylpyrrolidone, and polyetheramine were added to deionized water in a mass ratio of 17:2.5:5:90. The mixture was stirred at 50°C for 30 min to obtain a binder base liquid. Carboxylated nanowires were then added to the binder base liquid and ultrasonically dispersed to obtain a composite binder. The mass fraction of carboxylated nanowires in the composite binder was 4 wt%. The composite binder was coated onto the surface of a composite polyurethane base film 1 at a coating speed of 12 m / min. After coating, the film was dried at 80°C for 15 min and then cured at 100°C for 2 h to form a 10 μm thick adhesive layer 2 on the surface of the composite polyurethane base film 1.

[0200] (3) Mix a 70wt% nitric acid solution and a 98wt% sulfuric acid solution with a volume ratio of 1:4. After mixing evenly, a mixed acid solution is obtained. Graphene powder is dispersed in the mixed acid solution with a ratio of 1g:30L. The mixture is stirred at 60℃ for 2h to allow the reaction to occur. After the reaction is completed, the mixture is centrifuged. The precipitate after centrifugation is washed with 1mol / L sodium hydroxide solution until neutral. Then, it is vacuum dried at 70℃ for 8h to obtain activated graphene.

[0201] Dopamine hydrochloride was dissolved in Tris-HCl buffer solution with a pH of 9 to obtain a dopamine solution with a concentration of 4 mg / mL. Activated graphene was dispersed in the dopamine solution at a mass ratio of 1:1.2 to the activated graphene in the dopamine solution. The mixture was stirred at 35 °C for 8 h to induce polymerization. After the reaction was completed, the mixture was centrifuged and the precipitate was washed with deionized water until neutral. The precipitate was then vacuum dried at 70 °C for 8 h to obtain graphene coated with a polydopamine layer.

[0202] Glutaraldehyde was added to a Tris-HCl buffer solution with a pH of 9 to obtain a glutaraldehyde solution with a mass fraction of 1 wt%. Graphene-coated graphene was added to the glutaraldehyde solution at a mass ratio of 1:0.6. The mixture was stirred at 35°C for 2 h to induce a cross-linking reaction. After the reaction, the mixture was centrifuged, and the precipitate was washed with deionized water until neutral. The precipitate was then vacuum dried at 70°C for 8 h to obtain cross-linked coated graphene.

[0203] Cross-linked graphene was dispersed in a 1 wt% sodium dodecylbenzenesulfonate solution to obtain a cross-linked graphene dispersion with a concentration of 0.5 mg / mL. A 2 mol / L hydrochloric acid solution was added dropwise to adjust the pH to 1. Aniline monomer was then added to the dispersion, with a mass ratio of cross-linked graphene to aniline monomer of 1:3. The mixture was stirred for 1 minute. After 5 minutes, a precursor solution was obtained. Under stirring conditions, a 12 wt% ammonium persulfate solution was added dropwise to the precursor solution at a rate of 2 mL / min. The molar ratio of aniline monomer to ammonium persulfate in the ammonium persulfate solution was 1:1.1. After all the ammonium persulfate solution was added, the mixture was stirred for 15 hours to allow the monomer polymerization reaction to occur. After the reaction was completed, the mixture was centrifuged and the precipitate was washed with deionized water until neutral. Then, it was vacuum dried at 70 °C for 8 hours to obtain modified graphene.

[0204] (4) Sodium dodecylbenzenesulfonate, polyvinylpyrrolidone, anhydrous ethanol and deionized water are mixed evenly to obtain a composite solvent. The mass fraction of sodium dodecylbenzenesulfonate in the composite solvent is 1 wt%, the mass fraction of polyvinylpyrrolidone is 0.5 wt%, and the volume ratio of anhydrous ethanol and deionized water is 1:3. Modified graphene is dispersed in the composite solvent and stirred at 3000 rpm for 10 min to obtain a modified graphene dispersion. The concentration of modified graphene in the modified graphene dispersion is 3 mg / mL.

[0205] The modified graphene dispersion was repeatedly sprayed onto the surface of the adhesive layer 2. The spraying pressure was 0.4 MPa, the spraying distance was 20 cm, and the spraying was repeated 5 times. After spraying, it was dried at 60℃ for 5 min, then cured at 100℃ for 3 min, and finally hot-pressed at 90℃ and 8 MPa for 10 s to form a modified graphene conductive layer 3 with a thickness of 15 μm on the surface of the adhesive layer 2, resulting in the desired product. Figure 1 The conductive textile fabric shown.

[0206] Example 6

[0207] This embodiment provides a method for preparing conductive textile fabric. The difference from Embodiment 1 is that the mass ratio of nano-titanium dioxide to stearic acid in the stearic acid solution is adjusted to 1:0.1. Other operating steps and process parameters are exactly the same as in Embodiment 1.

[0208] Example 7

[0209] This embodiment provides a method for preparing conductive textile fabric. The difference from Embodiment 1 is that the mass ratio of nano-titanium dioxide to stearic acid in the stearic acid solution is adjusted to 1:0.3. Other operating steps and process parameters are exactly the same as in Embodiment 1.

[0210] Example 8

[0211] This embodiment provides a method for preparing conductive textile fabric. The difference from Embodiment 1 is that the mass ratio of polyurethane particles, modified nano titanium dioxide, and calcium stearate is adjusted to 100:6:1.5. Other operating steps and process parameters are exactly the same as in Embodiment 1.

[0212] Example 9

[0213] This embodiment provides a method for preparing conductive textile fabric. The difference from Embodiment 1 is that the mass ratio of polyurethane particles, modified nano titanium dioxide, and calcium stearate is adjusted to 100:12:1.5. Other operating steps and process parameters are exactly the same as in Embodiment 1.

[0214] Example 10

[0215] This embodiment provides a method for preparing conductive textile fabric. The difference from Embodiment 1 is that the mass fraction of carboxylated nanowires in the composite binder is adjusted to 1 wt%, while other operating steps and process parameters are exactly the same as in Embodiment 1.

[0216] Example 11

[0217] This embodiment provides a method for preparing conductive textile fabric. The difference from Embodiment 1 is that the mass fraction of carboxylated nanowires in the composite binder is adjusted to 5 wt%, while other operating steps and process parameters are exactly the same as in Embodiment 1.

[0218] Example 12

[0219] This embodiment provides a method for preparing conductive textile fabric. The difference from Embodiment 1 is that the mass ratio of activated graphene to dopamine hydrochloride in the dopamine solution is adjusted to 1:0.5. Other operating steps and process parameters are exactly the same as in Embodiment 1.

[0220] Example 13

[0221] This embodiment provides a method for preparing conductive textile fabric. The difference from Embodiment 1 is that the mass ratio of activated graphene to dopamine hydrochloride in the dopamine solution is adjusted to 1:1.5. Other operating steps and process parameters are exactly the same as in Embodiment 1.

[0222] Example 14

[0223] This embodiment provides a method for preparing conductive textile fabric. The difference from Example 1 is that the mass ratio of cross-linked coated graphene to aniline monomer in the cross-linked coated graphene dispersion is adjusted to 1:1. Other operating steps and process parameters are exactly the same as in Example 1.

[0224] Example 15

[0225] This embodiment provides a method for preparing conductive textile fabric. The difference from Example 1 is that the mass ratio of cross-linked coated graphene to aniline monomer in the cross-linked coated graphene dispersion is adjusted to 1:4. Other operating steps and process parameters are exactly the same as in Example 1.

[0226] The electrical conductivity and mechanical properties of the conductive textile fabrics prepared in Examples 1-15 were tested. The specific test steps are as follows:

[0227] (1) Surface resistance

[0228] The surface resistance of conductive textile fabric samples was tested using a high-resistivity meter, referring to the national standard GB / T22042-2008 "Test Method for Surface Resistivity of Clothing for Antistatic Performance". The test voltage was DC voltage 100±5V, the test temperature was 20±2℃, the noise level was 35±5%RH, the fabric sample size was 100mm×100mm, the fabric sample was flat and wrinkle-free, the electrode spacing was 25±0.5mm, and the parallel electrode method was used for testing. Five different positions were tested for each fabric sample, and the geometric mean was taken.

[0229] (2) Conductivity retention after 50 water washes

[0230] The fabric was washed using the washing method provided in the national standard GB / T 8629-2017 "Home Washing and Drying Procedures for Textile Testing" for 50 washes at a temperature of 40±3℃. Referring to the national standard GB / T 22042-2008 "Surface Resistivity Test Method for Antistatic Properties of Clothing", the surface resistance of the fabric samples before and after washing was tested under the above conditions. The conductivity retention rate of the fabric samples was calculated based on the surface resistance before and after washing.

[0231] (3) Tensile strength

[0232] The tensile strength of conductive textile fabric samples was tested using a universal testing machine, referring to the national standard GB / T3923.1-2013 "Textiles - Tensile Properties of Fabrics - Part 1: Determination of Breaking Strength and Elongation at Break (Strip Method)". The fabric sample size was 50mm × 200mm, the clamp spacing was 100mm, and the tensile speed was 100mm / min. The maximum breaking strength (N) was recorded when the fabric sample broke. The tensile strength was then determined based on the ratio of breaking strength to the cross-sectional area of ​​the fabric sample (mm²). 2 Calculate the tensile strength (MPa) of the fabric sample.

[0233] (4) interlayer peel strength

[0234] The interlaminar peel strength of conductive textile fabric samples was tested using a universal testing machine, referring to the textile industry standard FZ / T 80007.1-2006 "Test Method for Peel Strength of Adhesive-backed Garments". The fabric sample size was 25mm×150mm, the peel angle was 180°, the peel speed was 100mm / min, and the peeling was carried out at a constant tensile speed. The peel force curve was recorded, and the interlaminar peel strength (N / mm) of the fabric sample was calculated based on the average peel force and the sample width.

[0235] Table 1

[0236]

[0237]

[0238] As can be seen from the data in Table 1, the surface resistance of the conductive textile fabrics prepared in Examples 1-5 is much lower than that in Examples 6-15, while the conductivity retention, tensile strength, and interlaminar peel strength are much higher than those in Examples 6-15. This indicates that the conductive textile fabrics prepared in this invention have excellent conductivity and mechanical properties. This is because the nano-titanium dioxide is uniformly dispersed by appropriate stearic acid modification, and a three-dimensional conductive network is constructed in conjunction with graphene / polyaniline. Furthermore, the interpenetrating network is formed by crosslinking appropriate carboxylated nanowires with epoxy resin, which restricts the migration of conductive components.

[0239] The test data from Examples 1, 6, and 7 show that the surface resistance of the conductive textile fabric prepared in Example 1 is much lower than that in Examples 6 and 7, while its conductivity retention, tensile strength, and interlayer peel strength are much higher. This is because the amount of stearic acid added was adjusted in Examples 6 and 7. In Example 6, the amount of stearic acid was too small, leading to the agglomeration of nano-titanium dioxide and the breakage of the conductive network, ultimately resulting in an increase in the surface resistance of the conductive textile fabric. In Example 7, the amount of stearic acid was too large, weakening the entanglement of polyurethane molecular chains and generating microporous defects, ultimately causing a decrease in the tensile strength of the conductive textile fabric.

[0240] The test data from Examples 1, 8, and 9 show that the surface resistance of the conductive textile fabric prepared in Example 1 is much lower than that in Examples 8 and 9, while its conductivity retention, tensile strength, and interlaminar peel strength are much higher. This is because Examples 8 and 9 adjusted the amount of modified nano-titanium dioxide added. In Example 8, the amount of modified nano-titanium dioxide added was too small, resulting in insufficient mechanical reinforcement effect and ultimately a decrease in the tensile strength of the conductive textile fabric. In Example 9, the amount of modified nano-titanium dioxide added was too large, causing agglomeration of the modified nano-titanium dioxide, which also ultimately led to a decrease in the tensile strength of the conductive textile fabric.

[0241] The test data from Examples 1, 10, and 11 show that the surface resistance of the conductive textile fabric prepared in Example 1 is much lower than that in Examples 10 and 11, while its conductivity retention, tensile strength, and interlaminar peel strength are much higher. This is because Examples 10 and 11 adjusted the mass fraction of carboxylated nanowires in the composite binder. In Example 10, the amount of carboxylated nanowires added was too small, resulting in insufficient vertical conductive paths and ultimately increasing the surface resistance of the conductive textile fabric. In Example 11, the amount of carboxylated nanowires added was too large, causing stress concentration and ultimately reducing the interlaminar peel strength of the conductive textile fabric.

[0242] The test data from Examples 1, 12, and 13 show that the surface resistance of the conductive textile fabric prepared in Example 1 is much lower than that in Examples 12 and 13, while its conductivity retention, tensile strength, and interlayer peel strength are much higher. This is because Examples 12 and 13 adjusted the mass ratio of activated graphene to dopamine hydrochloride in the dopamine solution. In Example 12, the amount of dopamine was too small, resulting in incomplete coating of the graphene surface and ultimately a decrease in the tensile strength of the conductive textile fabric. In Example 13, the amount of dopamine was too large, forming an excessively thick insulating layer on the graphene surface, which ultimately increased the surface resistance of the conductive textile fabric.

[0243] The test data from Examples 1, 14, and 15 show that the surface resistance of the conductive textile fabric prepared in Example 1 is much lower than that in Examples 14 and 15, while its conductivity retention, tensile strength, and interlaminar peel strength are much higher. This is because Examples 14 and 15 adjusted the mass ratio of cross-linked coated graphene to aniline monomer in the cross-linked coated graphene dispersion. In Example 14, the amount of aniline monomer was too small, resulting in short polyaniline chains and discontinuous conductive networks, ultimately leading to an increase in the surface resistance of the conductive textile fabric. In Example 15, the amount of aniline monomer was too large, triggering side reactions and ultimately causing a decrease in the tensile strength of the conductive textile fabric.

[0244] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A graphene-based conductive textile fabric, characterized in that, The conductive textile fabric comprises a composite polyurethane base film, an adhesive layer, and a modified graphene conductive layer stacked sequentially. The composite polyurethane-based film is obtained by mixing polyurethane particles, stearic acid-modified nano-titanium dioxide and lubricant, and then sequentially melting and extruding and blow molding to form a film. The adhesive layer is formed by coating the surface of the composite polyurethane base film with a composite adhesive and then drying and curing it. The composite adhesive includes epoxy resin emulsion, polyvinylpyrrolidone, curing agent and carboxylated nanowires. The modified graphene conductive layer is formed by coating the surface of the adhesive layer with a modified graphene dispersion, followed by drying, curing, and hot pressing. The modified graphene dispersion is composed of modified graphene and a composite solvent. The modified graphene is obtained by sequentially modifying graphene powder through acid activation, dopamine coating modification, glutaraldehyde crosslinking modification, and polyaniline monomer polymerization coating modification. Preparation method of modified nano titanium dioxide: Stearic acid was dissolved in anhydrous ethanol, mixed, stirred, and heated to obtain a stearic acid solution. Nano-titanium dioxide was mixed with the stearic acid solution and ball-milled, followed by filtration, washing, and vacuum drying to obtain the modified nano-titanium dioxide. The mass ratio of nano-titanium dioxide to stearic acid in the stearic acid solution was 1:(0.15~0.25). The mass ratio of polyurethane particles, modified nano-titanium dioxide, and lubricant is 100:(8~10):(1.5~2.5); The carboxylated nanowires in the composite binder have a mass fraction of 3-4 wt%. The specific preparation method of modified graphene is as follows: graphene powder is activated and modified by mixed acid solution, coated with dopamine solution, and finally cross-linked with glutaraldehyde solution to obtain cross-linked coated graphene; the cross-linked coated graphene is in-situ polymerized and coated with aniline monomer and ammonium persulfate solution to obtain modified graphene. Cross-linked graphene was prepared using the following method: (1) Mix nitric acid solution and sulfuric acid solution evenly to obtain the mixed acid solution, disperse the graphene powder in the mixed acid solution, mix and stir and heat to react, and after the reaction is completed, perform centrifugation, alkaline washing and vacuum drying to obtain activated graphene; (2) Dissolve dopamine hydrochloride in Tris-HCl buffer to obtain a dopamine solution, disperse the activated graphene in the dopamine solution, mix and stir to produce a polymerization reaction, and after the reaction is completed, centrifuge, wash with deionized water and vacuum dry to obtain graphene coated with a polydopamine layer on the surface. (3) Add glutaraldehyde to Tris-HCl buffer solution to obtain glutaraldehyde solution, add the coated graphene to the glutaraldehyde solution, mix and stir to cause cross-linking reaction, and after the reaction is completed, centrifuge, wash with deionized water and vacuum dry to obtain the cross-linked coated graphene. The mass ratio of activated graphene to dopamine hydrochloride in the dopamine solution is 1:(1~1.2); The mass ratio of cross-linked coated graphene to aniline monomer in the cross-linked coated graphene dispersion is 1:(2~3).

2. The conductive textile fabric according to claim 1, characterized in that, The thickness of the composite polyurethane base film is 30~40μm; The thickness of the adhesive layer is 8~10μm; The thickness of the modified graphene conductive layer is 10~15μm.

3. A method for preparing a graphene-based conductive textile fabric as described in claim 1 or 2, characterized in that, Includes the following steps: (I) Modified nano-titanium dioxide was obtained by modifying nano-titanium dioxide with stearic acid. Polyurethane particles, modified nano-titanium dioxide and lubricant were mixed to obtain a mixture. The mixture was then melt-extruded, granulated and blow-molded into a film to obtain a composite polyurethane base film. (II) Silicon carbide nanowires were modified with hydrogen peroxide and sodium hydroxide to obtain carboxylated nanowires; epoxy resin emulsion, polyvinylpyrrolidone, carboxylated nanowires, curing agent and deionized water were mixed to obtain a composite adhesive; the composite adhesive was coated on the surface of the composite polyurethane base film and formed an adhesive layer after drying and curing. (III) The graphene powder was activated and modified by mixed acid solution, coated with dopamine solution, and finally cross-linked with glutaraldehyde solution to obtain cross-linked coated graphene; the cross-linked coated graphene was in-situ polymerized and coated with aniline monomer and ammonium persulfate solution to obtain modified graphene. Cross-linked graphene was prepared using the following method: Step (1) Mix nitric acid solution and sulfuric acid solution evenly to obtain the mixed acid solution. Disperse the graphene powder in the mixed acid solution, mix and stir and heat to react. After the reaction is completed, centrifuge, wash with alkaline solution and vacuum dry to obtain activated graphene. Step (2) Dissolve dopamine hydrochloride in Tris-HCl buffer to obtain a dopamine solution. Disperse the activated graphene in the dopamine solution and mix and stir to produce a polymerization reaction. After the reaction is completed, centrifuge, wash with deionized water and vacuum dry to obtain graphene coated with a polydopamine layer on the surface. Step (3) Add glutaraldehyde to Tris-HCl buffer to obtain glutaraldehyde solution, add the coated graphene to the glutaraldehyde solution, mix and stir to cause cross-linking reaction, after the reaction is completed, centrifuge, wash with deionized water and vacuum dry to obtain the cross-linked coated graphene; The mass ratio of activated graphene to dopamine hydrochloride in the dopamine solution is 1:(1~1.2); The mass ratio of cross-linked coated graphene to the aniline monomer in the cross-linked coated graphene dispersion is 1:(2~3); (IV) The modified graphene is dispersed in a composite solvent, stirred to obtain a dispersion, coated on the surface of the adhesive layer, dried, cured and hot-pressed to form a modified graphene conductive layer, and the conductive textile fabric is obtained.

4. The preparation method according to claim 3, characterized in that, In the preparation method of modified nano-titanium dioxide in step (I), the mixing and stirring time of stearic acid and anhydrous ethanol is 40~50 min; Alternatively, the temperature for mixing and stirring the stearic acid and anhydrous ethanol is 60~70℃; Alternatively, the stearic acid in the stearic acid solution has a mass fraction of 3-4 wt%; Alternatively, the ball milling speed for mixing the nano-titanium dioxide and the stearic acid solution is 250~350 rpm; Alternatively, the ball milling time for mixing the nano-titanium dioxide and the stearic acid solution is 3-4 hours.

5. The preparation method according to claim 3, characterized in that, In step (I), the lubricant comprises calcium stearate and / or zinc stearate; Alternatively, the mixing temperature of the polyurethane particles, the modified nano-titanium dioxide, and the lubricant is 130~140℃; Alternatively, the mixing time of the polyurethane particles, the modified nano-titanium dioxide, and the lubricant is 40-50 minutes; Alternatively, the melt extrusion of the mixture is carried out in a screw extruder; the barrel of the screw extruder is divided into a first zone, a second zone, and a third zone with different temperatures along the flow direction of the mixture; the temperature of the first zone is 165~175℃; the temperature of the second zone is 180~190℃; the temperature of the third zone is 195~205℃; and the screw speed of the screw extruder is 35~45 rpm. Alternatively, the blow-up ratio of the blown film is (2.5~3.5):1; Alternatively, the thickness of the composite polyurethane base film is 30~40μm.

6. The preparation method according to claim 3, characterized in that, In step (II), the carboxylated nanowires are prepared using the following method: A hydrogen peroxide solution and a sodium hydroxide solution were mixed evenly to obtain a modified solution. The silicon carbide nanowires were added to the modified solution, and after ultrasonic dispersion, they were transferred to a reaction vessel for high-temperature reaction. After the reaction was completed, the nanowires were filtered, washed with deionized water, and vacuum dried to obtain the carboxylated nanowires. The hydrogen peroxide solution has a mass fraction of 6-8 wt%; The sodium hydroxide solution has a mass fraction of 7-9 wt%. The volume ratio of the hydrogen peroxide solution to the sodium hydroxide solution is 1:(1.3~1.5); The mass ratio of the silicon carbide nanowires to the modified solution is 1:(30~40); The ultrasonic power for ultrasonic dispersion of the silicon carbide nanowires in the modified solution is 300~400W. The ultrasonic dispersion of the silicon carbide nanowires in the modified solution is performed for 40-50 minutes. The temperature of the high-temperature reaction is 120~130℃; The high-temperature reaction takes 5-6 hours.

7. The preparation method according to claim 3, characterized in that, In step (II), the composite adhesive is prepared by the following method: Epoxy resin emulsion, polyvinylpyrrolidone, and curing agent were added to deionized water, mixed, stirred, and heated to obtain a binder base liquid; then carboxylated nanowires were added to the binder base liquid, and the mixture was ultrasonically dispersed to obtain the composite binder; The mass ratio of the epoxy resin emulsion, the polyvinylpyrrolidone, the curing agent, and the deionized water is (15~17):(1.5~2.5):(3~5):(80~90); The curing agent includes polyetheramine; The epoxy resin emulsion, the polyvinylpyrrolidone, the curing agent and the deionized water are mixed and stirred for 30 to 40 minutes. The mixing and stirring temperature of the epoxy resin emulsion, the polyvinylpyrrolidone, the curing agent and the deionized water is 40~50℃; The composite adhesive is applied by transfer coating; The coating speed of the composite adhesive is 10~12m / min; The drying temperature of the composite adhesive after coating is 70~80℃; The drying time of the composite adhesive after coating is 15-25 minutes; The curing temperature is 90~100℃; The curing time is 2-3 hours; The thickness of the adhesive layer is 8~10μm.

8. The preparation method according to claim 3, characterized in that, In step (1) of the preparation of cross-linked coated graphene in step (III), the mass fraction of the nitric acid solution is 65~70 wt%. The sulfuric acid solution has a mass fraction of 95-98 wt%. The volume ratio of the nitric acid solution to the sulfuric acid solution is 1:(3~4); The graphene powder and the mixed acid solution are mixed and stirred for 2-3 hours. The mixing temperature of the graphene powder and the mixed acid solution is 50~60℃; In step (2), the pH value of the Tris-HCl buffer solution is 8~9; The concentration of dopamine hydrochloride in the dopamine solution is 3-4 mg / mL; The activated graphene and the dopamine solution are mixed and stirred for 8-10 hours. The temperature for mixing and stirring the activated graphene and the dopamine solution is 25~35℃; In step (3), the mass fraction of glutaraldehyde in the glutaraldehyde solution is 0.5~1wt%; The mass ratio of the coated graphene to the glutaraldehyde in the glutaraldehyde solution is 1:(0.5~0.6); The mixing and stirring time for the coated graphene and the glutaraldehyde solution is 2-4 hours; The temperature for mixing and stirring the coated graphene and the glutaraldehyde solution is 25~35℃.

9. The preparation method according to claim 3, characterized in that, In step (III), the modified graphene is prepared by the following method: The cross-linked graphene was dispersed in a sodium dodecylbenzenesulfonate solution to obtain a cross-linked graphene dispersion. Hydrochloric acid solution was added dropwise to the cross-linked graphene dispersion to adjust its pH value. Aniline monomer was added to the cross-linked graphene dispersion and mixed evenly to obtain a precursor solution. Ammonium persulfate solution was added dropwise to the precursor solution under stirring to induce monomer polymerization. After the reaction was completed, the modified graphene was obtained by centrifugation, washing with deionized water, and vacuum drying. The sodium dodecylbenzenesulfonate solution contains 0.5-1 wt% sodium dodecylbenzenesulfonate. The concentration of cross-linked coated graphene in the cross-linked graphene dispersion is 0.3~0.5 mg / mL; Hydrochloric acid solution was added dropwise to the cross-linked graphene dispersion to adjust its pH value to 1-2; The concentration of the hydrochloric acid solution is 1~2 mol / L; The mixing time between the cross-linked graphene dispersion and the aniline monomer is 10-15 min; The mass fraction of the ammonium persulfate solution is 10-12 wt%. The dropping rate of the ammonium persulfate solution is 1~2 mL / min; The molar ratio of the aniline monomer to the ammonium persulfate in the ammonium persulfate solution is 1:(1~1.1); After all the ammonium persulfate solution has been added, continue mixing and stirring for 10-15 hours.

10. The preparation method according to claim 3, characterized in that, In step (IV), the composite solvent is composed of sodium dodecylbenzenesulfonate, polyvinylpyrrolidone, anhydrous ethanol and deionized water; The mass fraction of sodium dodecylbenzenesulfonate in the composite solvent is 0.8~1wt%; The mass fraction of polyvinylpyrrolidone in the composite solvent is 0.3~0.5 wt%. The volume ratio of anhydrous ethanol to deionized water in the composite solvent is 1:(2~3); The concentration of the modified graphene in the modified graphene dispersion is 2~3 mg / mL; The speed of high-speed stirring of the modified graphene and the composite solvent is 2000~3000 rpm; The high-speed stirring time of the modified graphene and the composite solvent is 10-15 min; The modified graphene dispersion is coated by reciprocating spraying. The spraying pressure of the modified graphene dispersion is 0.3~0.4 MPa; The spraying distance of the modified graphene dispersion is 10~20cm; The modified graphene dispersion is sprayed 3 to 5 times. The drying temperature is 50~60℃; The drying time is 5-8 minutes; The curing temperature is 90~100℃; The curing time is 3-5 minutes; The hot pressing temperature is 80~90℃; The hot pressing time is 10~20s; The pressure of the hot pressing is 6~8MPa; The thickness of the modified graphene conductive layer is 10~15μm.

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