Preparation method of strain sensing fabric with health monitoring function

Abstract

The invention discloses a preparation method of a strain sensing fabric with a health monitoring function, and the method comprises the following steps: 1, synthesizing a multi-dimensional conductive nano material, and mixing zero-dimensional silver nanoparticles, one-dimensional silver nanowires and two-dimensional MXene to obtain a dispersion liquid with a certain concentration; 2, dissolving a fiber-forming high-molecular polymer by using a wet spinning device, uniformly mixing the dissolved fiber-forming high-molecular polymer with the multi-dimensional conductive nano material in the step 1, and extruding the conductive spinning solution through a propulsion pump to obtain a high-elastic conductive wet spinning fiber; thirdly, weaving the wet spinning fibers through a digital weaving machine, and dynamically adjusting the warp tension to reduce the end breakage rate and the hairiness index to obtain the strain sensing fabric with the health monitoring function. The strain sensing fabric prepared by the invention is directly prepared by adopting a wet spinning process and a digital weaving technology, is high in practicability and can be used for real-time monitoring and transmission of human health data.

Description

Technical Field

[0001] The present invention belongs to the field of intelligent textile technology, and specifically refers to a method for preparing a strain sensing fabric with health monitoring function. Background Art

[0002] Smart wearable devices have an increasing market share due to their portability and timely health monitoring. To overcome this, 90% of existing smart wearable devices use polymer films (such as PDMS) with a moisture permeability of less than 50g / (m 2 ·d)(GB / T 12704.2-2009), long-term wearing can cause contact dermatitis. Therefore, the extensive use of smart wearable devices is accompanied by widespread concern about their comfort and functionality. Textiles have natural advantages such as breathability, moisture permeability, skin-friendliness, and strong environmental stability, which can largely avoid the occurrence of the above problems.

[0003] Traditional smart wearable textiles, based on ordinary textiles, use techniques such as impregnation and coating to bond conductive materials to textiles. This results in inaccurate signal acquisition, poor skin permeability, and a susceptibility to skin diseases such as dermatitis or eczema, reducing the real-time and accuracy of health monitoring. To address these issues, wet spinning and digital weaving technologies can be used to give fabrics conductive and breathable properties, avoiding the sensitivity drift caused by fiber damage in the traditional weaving process. Strain sensing fabrics are elastic in both the warp and weft directions, adapting to deformations of varying scales, such as human joint bending and pulse beating. At the same time, digital weaving technology achieves low-damage weaving through dynamic warp tension control and broken end detection, improving breathability, moisture permeability, and wearing comfort.

[0004] Wet spinning technology has the advantages of a wide range of spinnable raw materials and strong adjustability of fiber properties. It can produce highly elastic and highly conductive fibers by mixed spinning of multidimensional nanomaterials and fiber-forming polymers. Combined with digital weaving technology, it can dynamically adjust warp tension, breakage, and hairiness to produce highly sensitive strain-sensing fabrics, effectively improving the accuracy of health monitoring and wearing comfort. Summary of the Invention

[0005] In view of the above situation, in order to overcome the defects of the prior art, the present invention provides a method for preparing a strain sensing fabric with a health monitoring function. The strain sensing fabric prepared by this method has health monitoring and air permeability and moisture permeability functions.

[0006] The technical solution adopted by the present invention is as follows: A method for preparing a strain sensing fabric with health monitoring function proposed by the present invention comprises the following steps:

[0007] Step 1: Synthesize one-dimensional silver nanowires using a polyol method, synthesize two-dimensional MXene nanosheets using a hydrochloric acid / lithium fluoride system, add silver nitrate solution to the MXene dispersion for in-situ reduction to generate zero-dimensional silver nanoparticles, and mix the three and stir them evenly to prepare a multidimensional conductive nanomaterial;

[0008] Step 2: Adding a fiber-forming polymer to a solvent, then adding a multidimensional conductive nanomaterial, dissolving and stirring uniformly to obtain a wet spinning solution, and using a wet spinning device to prepare the spinning solution into a wet-spun fiber with high elasticity and high conductivity;

[0009] Step 3: After drying, the above fibers are used as warp and weft yarns, and spinning parameters such as warp tension are adjusted on a digital loom to weave a strain-sensing fabric with air and moisture permeability.

[0010] Preferably, the scale range of the multidimensional conductive nanomaterial described in step 1 is: the average diameter of zero-dimensional silver nanoparticles is 50 to 400 nm; the average diameter of one-dimensional silver nanowires is 50 to 400 nm; the microscopic morphology of two-dimensional MXene nanosheets is accordion-shaped, and the average interlayer spacing is less than 200 nm.

[0011] Preferably, the average diameter of the wet-spun fibers in step 2 is 0.2 to 0.8 mm, and the diameter is adjustable.

[0012] Preferably, the strain sensing fabric with health monitoring function described in step three has a warp density of 6 to 12 threads / cm and a weft density of 15 to 30 threads / cm.

[0013] Preferably, the one-dimensional silver nanowires described in step 1 are synthesized by heating 0.2-0.4 g polyvinyl pyrrolidone, 0.1-0.3 g silver nitrate, and 10-30 ml ethylene glycol at 150-200 ° C for 2 h to obtain silver nanowires with a certain aspect ratio, and dispersing them in ethanol, with a dispersion concentration of 0.5-10 mg / ml.

[0014] Preferably, in the synthesis of the two-dimensional MXene in the hydrochloric acid / lithium fluoride system described in step 1, the concentration of hydrochloric acid during the reaction is 7 to 10 mol / L, and the prepared MXene is dispersed in ethanol at a concentration of 2 to 12 mg / ml.

[0015] Preferably, the synthesis of the zero-dimensional silver nanoparticles described in step 1 adopts an in-situ reduction method using MXene as a reducing agent, and the concentration of silver nitrate is 1 to 5 mg / ml, which is slowly dripped into the MXene dispersion. After 5 to 40 minutes of oscillation and ultrasonic treatment, the silver nanoparticles are evenly distributed on the surface of the MXene nanosheets.

[0016] Preferably, the wet spinning fiber-forming polymer described in step 2 is any one or a combination of thermoplastic polyurethane, polyethylene, polyacrylonitrile, polyester, polyvinyl alcohol, and polyamide, the solvent system used is one or more of N,N-dimethylformamide, dimethylacetamide, and tetrahydrofuran, the mass percentage of the spinning solution concentration is 7 to 20%, the coagulation bath uses any one or a combination of water, ethanol, and dimethyl sulfoxide, the spinneret diameter is 0.1 to 0.5 mm, the coagulation bath temperature is 20 to 50°C, the propulsion pump extrusion speed is 20 to 150 mm / s, and the drafting ratio is 2.0 to 4.5X.

[0017] Preferably, the strain sensing fabric described in step 3 is woven using a digital loom, and the warp tension is dynamically adjusted to reduce the breakage rate and hairiness index, with the weaving breakage rate being less than 5% and the hairiness index being ≤2.0.

[0018] Preferably, the elastic elongation of the wet-spun fiber in step 2 is 80% to 300%, and the tensile strength at break is greater than 20 MPa; the elastic elongation of the strain sensing fabric is 30% to 160%, and the tensile strength at break is greater than 50 MPa.

[0019] Preferably, the wet-spun fiber sensitivity in step 2 is greater than 100, the strain sensing fabric sensitivity is greater than 80, and the conductivity is greater than 5000 S / cm.

[0020] Preferably, the indicators of health monitoring of the strain sensing fabric described in step three include large-scale strain (muscle and joint movement) and small-scale strain (physiological signals such as heartbeat, pulse, and breathing).

[0021] Preferably, the strain sensing fabric described in step 3 is adjusted according to the warp and weft yarn densities to improve comfort during wearing, and its moisture permeability is greater than 5100 g / m2 / d.

[0022] Preferably, the strain sensing fabric described in step three can be made into different forms such as ECG vests, wristbands, gloves, joint protection belts, etc. according to different monitoring parts.

[0023] The strain sensing fabric with health monitoring function prepared by the present invention includes highly elastic fibers with adjustable structure, to which multidimensional conductive nanomaterials are added to adjust the interface impedance matching and form a multi-level conductive coupling path, thereby achieving uniform control of the surface charge distribution of the fibers during the wet spinning process, giving the fibers high strain sensitivity, and dynamically optimizing the warp tension during the weaving process to produce a strain sensing fabric with a regular structure.

[0024] The strain sensing fabric with health monitoring function produced by the present invention can be cut into different clothing and accessories according to actual needs. It has a total thickness of 400 to 900 μm, an elastic elongation of 30% to 160%, a sensitivity of more than 80, an electrical conductivity of more than 5000 S / cm, and a moisture permeability of more than 5100 g / m2 / d.

[0025] The beneficial effects achieved by the present invention using the above structure are as follows:

[0026] (1) The strain sensing fabric of the present invention is composited with a highly elastic polymer and a multi-dimensional conductive nanomaterial at the fiber level to form a multi-level conductive coupling path, thereby endowing the fabric with a strain sensing function;

[0027] (2) The strain sensing fabric of the present invention has uniform sensing in the warp and weft directions, is breathable and moisture-permeable, is comfortable to wear, and is more in line with the deformation characteristics of different parts of the human body;

[0028] (3) The strain sensing fabric prepared by the present invention is directly prepared by wet spinning process and digital weaving technology, has strong practicality, and can be used for real-time monitoring and transmission of human health data. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 These are electron microscope images of multidimensional conductive nanomaterials. (a) shows the microscopic morphology of zero-dimensional and two-dimensional MXene in-situ reduced silver nanoparticles; (b) shows the microscopic morphology of two-dimensional silver nanowires.

[0030] Figure 2 This is a real picture of wet-spun fiber and its microscopic surface morphology.

[0031] Figure 3 This is a real picture of the strain sensing fabric.

[0032] Figure 4 Data graph of changes in finger bending signals monitored by strain sensing fabric.

[0033] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0035] The raw materials used in the following examples are all commercially available products.

[0036] The polyvinyl pyrrolidone, ethylene glycol, silver nitrate, sodium chloride, and lithium fluoride used in Examples 1 to 7 were all provided by Shanghai MacLean Biochemical Materials Technology Co., Ltd.; hydrochloric acid was provided by Huzhou Shuanglin Chemical Technology Co., Ltd., and Ti3AlC2 was provided by Laizhou Kaixi Ceramic Materials Co., Ltd.; polyurethane, polyester, and polyacrylonitrile were all provided by BASF Group of Germany; N,N-dimethylformamide and anhydrous ethanol were all provided by Shanghai Aladdin Biochemical Technology Co., Ltd.

[0037] Example 1

[0038] A method for preparing a strain sensing fabric with health monitoring function, comprising the following steps:

[0039] Step 1: For the synthesis of one-dimensional silver nanowires, first add 0.3g of polyvinyl pyrrolidone to 20ml of ethylene glycol and dissolve it at 40°C, add 0.1g of silver nitrate, place it in a flask in the dark and stir for 20min, then add 0.2ml of 0.1mol / L sodium chloride aqueous solution, heat the flask at 170°C for 2h, filter and wash the precipitate, and disperse it in ethanol to prepare a silver nanowire dispersion with a concentration of 5.5mg / ml; For the synthesis of two-dimensional MXene, add 3.0g of lithium fluoride to 40ml of 9mol / L dilute hydrochloric acid, and then add 1.0g of Ti3 AlC2 powder was magnetically stirred in an oil bath at 35°C for 24 hours at 200 rpm / min. The solution was then centrifuged at 5000 rpm for 5 minutes until the supernatant pH reached >6. The precipitate was then placed in 50ml of ethanol and sonicated for 30 minutes to obtain a 10mg / ml MXene dispersion. For the synthesis of zero-dimensional silver nanoparticles, 2.5ml of a 2.5mg / ml silver nitrate solution was slowly added dropwise to 10ml of a 10mg / ml MXene dispersion at room temperature. After sonication and oscillation for 30 minutes, an 8.5mg / ml MXene / silver nanoparticle dispersion was obtained. The silver nanowire dispersion and the MXene / silver nanoparticle dispersion were mixed in a 1:1 volume ratio to obtain a 7.0mg / ml multidimensional conductive nanomaterial dispersion. The dispersion was centrifuged and dried in a vacuum at 50°C to obtain a multidimensional conductive powder.

[0040] The second step: adding polyurethane to N,N-dimethylformamide, stirring and dissolving at 40°C, and then adding multidimensional conductive powder, wherein the mass ratio of multidimensional conductive powder to polyurethane is 3:1, and fully stirring to obtain a wet spinning solution with a mass fraction of 16%; placing the spinning solution in a 20ml syringe, adjusting the extrusion speed of the wet spinning propulsion pump to 30ml / h, and using a 0.51mm syringe needle to uniformly extrude the spinning solution into a coagulation bath of deionized water and anhydrous ethanol (volume ratio of 7:3), with a drafting ratio of 2.0 times, so that the spinning solution is quickly formed in the coagulation bath, and then placed in a ventilated environment at room temperature to dry for 24h to obtain a wet-spun fiber with a diameter of 0.3mm.

[0041] The third step is to warp the wet-spun fibers to arrange them neatly, and then weave them on a digital loom using plain weave. The warp density is set to 8 yarns / cm and the weft density is set to 24 yarns / cm. The warp tension is dynamically adjusted according to the breakage rate and hairiness index during the weaving process to ensure the structural uniformity of the fabric during the weaving process, thereby producing a strain-sensing fabric.

[0042] The strain sensing fabric with health monitoring function is thus obtained. The warp and weft yarns are evenly arranged, and there are multi-level conductive coupling paths at the fiber level, which enables the fabric to achieve conductive connectivity under high strain. The fabric thickness is 700μm, the elastic elongation is 70%, the sensitivity is 102 at this elongation, and the conductivity is 6000S / cm. It can identify the human body's pulse rate per minute, gestures, and running frequency, realizing non-destructive health monitoring. According to the national standard GB / T12704.2-2009 positive cup method test, the strain sensing fabric has a moisture permeability flux of 7000g / m2 / d, which is comfortable to wear.

[0043] Example 2

[0044] A method for preparing a strain sensing fabric with health monitoring function, comprising the following steps:

[0045] Step 1: For the synthesis of one-dimensional silver nanowires, first add 0.3g of polyvinyl pyrrolidone to 20ml of ethylene glycol and dissolve it at 40°C, add 0.2g of silver nitrate, place it in a flask in the dark and stir for 20min, then add 0.1ml of 0.1mol / L sodium chloride aqueous solution, heat the flask at 170°C for 2h, filter and wash the precipitate, and disperse it in ethanol to prepare a silver nanowire dispersion with a concentration of 6.0mg / ml; for the synthesis of two-dimensional MXene, add 3.0g of lithium fluoride to 40ml of 9mol / L dilute hydrochloric acid, and then add 1.5g of Ti3 AlC2 powder was magnetically stirred in an oil bath at 35°C for 24 hours at 200 rpm / min. The solution was then centrifuged at 5000 rpm for 5 minutes until the supernatant pH was >6. The precipitate was then placed in 50ml of ethanol and sonicated for 30 minutes to obtain a 10mg / ml MXene dispersion. For the synthesis of zero-dimensional silver nanoparticles, 2.5ml and 3.0mg / ml silver nitrate solutions were slowly added dropwise to 10ml and 10mg / ml MXene dispersions at room temperature. After sonication and oscillation for 30 minutes, an 8.5mg / ml MXene / silver nanoparticle dispersion was obtained. The silver nanowire dispersion and the MXene / silver nanoparticle dispersion were mixed in a 1:1 volume ratio to obtain an 8.0mg / ml multidimensional conductive nanomaterial dispersion. The dispersion was centrifuged and dried in a vacuum at 50°C to obtain a multidimensional conductive powder.

[0046] The second step: adding polyurethane to N,N-dimethylformamide, stirring and dissolving at 40°C, and then adding multidimensional conductive powder, wherein the mass ratio of multidimensional conductive powder to polyurethane is 2:1, and fully stirring to obtain a wet spinning solution with a mass fraction of 15%; placing the spinning solution in a 20ml syringe, adjusting the extrusion speed of the wet spinning propulsion pump to 30ml / h, and using a 0.51mm syringe needle to uniformly extrude the spinning solution into a coagulation bath of deionized water and anhydrous ethanol (volume ratio of 7:3), with a drafting ratio of 3.0 times, so that the spinning solution is quickly formed in the coagulation bath, and then placed in a ventilated environment at room temperature to dry for 24h to obtain a wet-spun fiber with a diameter of 0.25mm.

[0047] The third step is to warp the wet-spun fibers to arrange them neatly, and then weave them on a digital loom using plain weave. The warp density is set to 8 yarns / cm and the weft density is set to 25 yarns / cm. The warp tension is dynamically adjusted according to the breakage rate and hairiness index during the weaving process to ensure the structural uniformity of the fabric during the weaving process, thereby producing a strain-sensing fabric.

[0048] The strain sensing fabric with health monitoring function is thus obtained. The warp and weft yarns are evenly arranged, and there are multi-level conductive coupling paths at the fiber level, which enables the fabric to achieve conductive connectivity under high strain. The fabric thickness is 650μm, the elastic elongation is 110%, the sensitivity is 93 at this elongation, and the conductivity is 5500S / cm. It can identify the human body's pulse rate per minute, gestures, and running frequency, realizing non-destructive health monitoring. According to the national standard GB / T12704.2-2009 positive cup method test, the strain sensing fabric has a moisture permeability flux of 8300g / m2 / d, which is comfortable to wear.

[0049] Example 3

[0050] A method for preparing a strain sensing fabric with health monitoring function, comprising the following steps:

[0051] Step 1: For the synthesis of one-dimensional silver nanowires, first add 0.3g of polyvinyl pyrrolidone to 20ml of ethylene glycol and dissolve it at 40°C, add 0.1g of silver nitrate, place it in a flask in the dark and stir for 20min, then add 0.2ml of 0.1mol / L sodium chloride aqueous solution, heat the flask at 170°C for 2h, filter and wash the precipitate, and disperse it in ethanol to prepare a silver nanowire dispersion with a concentration of 5.5mg / ml; for the synthesis of two-dimensional MXene, add 2.0g of lithium fluoride to 40ml of 9mol / L dilute hydrochloric acid, and then add 1.0g of Ti3 AlC2 powder was magnetically stirred in an oil bath at 35°C for 24 hours at 200 rpm / min. The solution was then centrifuged at 5000 rpm for 5 minutes until the supernatant pH reached >6. The precipitate was then placed in 50ml of ethanol and sonicated for 30 minutes to obtain a 10mg / ml MXene dispersion. For the synthesis of zero-dimensional silver nanoparticles, 2.5ml of a 2.0mg / ml silver nitrate solution was slowly added dropwise to a 10ml of a 10mg / ml MXene dispersion at room temperature. After sonication and oscillation for 30 minutes, an 8.5mg / ml MXene / silver nanoparticle dispersion was obtained. The silver nanowire dispersion and the MXene / silver nanoparticle dispersion were mixed in a 2:1 volume ratio to obtain a 7.0mg / ml multidimensional conductive nanomaterial dispersion. The dispersion was centrifuged and dried in a vacuum at 50°C to obtain a multidimensional conductive powder.

[0052] The second step: adding polyurethane to N,N-dimethylformamide, stirring and dissolving at 40°C, and then adding multidimensional conductive powder, wherein the mass ratio of multidimensional conductive powder to polyurethane is 4:1, and fully stirring to obtain a wet spinning solution with a mass fraction of 17%; placing the spinning solution in a 20ml syringe, adjusting the extrusion speed of the wet spinning propulsion pump to 25ml / h, and using a 0.51mm syringe needle to uniformly extrude the spinning solution into a coagulation bath of deionized water and anhydrous ethanol (volume ratio of 7:3), with a drafting ratio of 2.0 times, so that the spinning solution is quickly formed in the coagulation bath, and then placed in a ventilated environment at room temperature to dry for 24h to obtain a wet-spun fiber with a diameter of 0.3mm.

[0053] The third step is to warp the wet-spun fibers to arrange them neatly, and then weave them on a digital loom using plain weave. The warp density is set to 10 yarns / cm and the weft density is set to 20 yarns / cm. The warp tension is dynamically adjusted according to the breakage rate and hairiness index during the weaving process to ensure the structural uniformity of the fabric during the weaving process, thereby producing a strain-sensing fabric.

[0054] The strain sensing fabric with health monitoring function is thus obtained. The warp and weft yarns are evenly arranged, and there are multi-level conductive coupling paths at the fiber level, which enables the fabric to achieve conductive connectivity under high strain. The fabric has a thickness of 700μm and an elastic elongation of 60%. At this elongation, the sensitivity is 156 and the conductivity is 9300S / cm. It can identify the human body's pulse rate per minute, gestures, and running frequency to achieve non-destructive health monitoring. According to the national standard GB / T12704.2-2009 positive cup method test, the strain sensing fabric has a moisture permeability flux of 7500g / m2 / d, which is comfortable to wear.

[0055] Example 4

[0056] A method for preparing a strain sensing fabric with health monitoring function, comprising the following steps:

[0057] Step 1: For the synthesis of one-dimensional silver nanowires, first add 0.2g of polyvinyl pyrrolidone to 20ml of ethylene glycol and dissolve it at 40°C, add 0.1g of silver nitrate, place it in a flask in the dark and stir for 20min, then add 0.2ml of 0.1mol / L sodium chloride aqueous solution, heat the flask at 170°C for 2h, filter and wash the precipitate, and disperse it in ethanol to prepare a silver nanowire dispersion with a concentration of 5.0mg / ml; For the synthesis of two-dimensional MXene, add 3.0g of lithium fluoride to 40ml of 9mol / L dilute hydrochloric acid, and then add 1.0g of Ti3 AlC2 powder was magnetically stirred in an oil bath at 35°C for 24 hours at 200 rpm / min. The solution was then centrifuged at 5000 rpm for 5 minutes until the supernatant pH reached >6. The precipitate was then placed in 50ml of ethanol and sonicated for 30 minutes to obtain a 10mg / ml MXene dispersion. For the synthesis of zero-dimensional silver nanoparticles, 2.5ml of a 2.5mg / ml silver nitrate solution was slowly added dropwise to 10ml of a 10mg / ml MXene dispersion at room temperature. After sonication and oscillation for 30 minutes, an 8.5mg / ml MXene / silver nanoparticle dispersion was obtained. The silver nanowire dispersion and the MXene / silver nanoparticle dispersion were mixed in a 2:1 volume ratio to obtain a 9.0mg / ml multidimensional conductive nanomaterial dispersion. The dispersion was centrifuged and dried in a vacuum at 50°C to obtain a multidimensional conductive powder.

[0058] The second step: adding polyester to N,N-dimethylformamide, stirring and dissolving at 40°C, and then adding multidimensional conductive powder, wherein the mass ratio of multidimensional conductive powder to polyester is 3:1, and fully stirring to obtain a wet spinning solution with a mass fraction of 16%; placing the spinning solution in a 20ml syringe, adjusting the extrusion speed of the wet spinning propulsion pump to 30ml / h, and using a 0.51mm syringe needle to uniformly extrude the spinning solution into a coagulation bath of deionized water and anhydrous ethanol (volume ratio of 7:3), with a drafting ratio of 3.0 times, so that the spinning solution is quickly formed in the coagulation bath, and then placed in a ventilated environment at room temperature to dry for 24h to obtain a wet-spun fiber with a diameter of 0.35mm.

[0059] The third step is to warp the wet-spun fibers to arrange them neatly, and then weave them on a digital loom using plain weave. The warp density is set to 8 yarns / cm and the weft density is set to 17 yarns / cm. The warp tension is dynamically adjusted according to the breakage rate and hairiness index during the weaving process to ensure the structural uniformity of the fabric during the weaving process, thereby producing a strain-sensing fabric.

[0060] The strain sensing fabric with health monitoring function is thus obtained. The warp and weft yarns are evenly arranged, and there are multi-level conductive coupling paths at the fiber level, which enables the fabric to achieve conductive connectivity under high strain. The fabric thickness is 800μm, the elastic elongation is 75%, the sensitivity is 120 at this elongation, and the conductivity is 6600S / cm. It can identify the human body's pulse rate per minute, gestures, and running frequency to achieve non-destructive health monitoring. According to the national standard GB / T12704.2-2009 positive cup method test, the strain sensing fabric has a moisture permeability flux of 6500g / m2 / d, which is comfortable to wear.

[0061] Example 5

[0062] A method for preparing a strain sensing fabric with health monitoring function, comprising the following steps:

[0063] Step 1: For the synthesis of one-dimensional silver nanowires, first add 0.2g of polyvinyl pyrrolidone to 20ml of ethylene glycol and dissolve it at 40°C, add 0.2g of silver nitrate, place it in a flask in the dark and stir for 20min, then add 0.2ml of 0.1mol / L sodium chloride aqueous solution, heat the flask at 170°C for 2h, filter and wash the precipitate, and disperse it in ethanol to prepare a silver nanowire dispersion with a concentration of 7.0mg / ml; For the synthesis of two-dimensional MXene, add 3.0g of lithium fluoride to 40ml of 9mol / L dilute hydrochloric acid, and then add 1.5g of Ti3 AlC2 powder was magnetically stirred in an oil bath at 35°C for 24 hours at 200 rpm / min. The solution was then centrifuged at 5000 rpm for 5 minutes until the supernatant pH reached >6. The precipitate was then placed in 50ml of ethanol and sonicated for 30 minutes to obtain a 10mg / ml MXene dispersion. For the synthesis of zero-dimensional silver nanoparticles, 2.5ml of a 2.0mg / ml silver nitrate solution was slowly added dropwise to a 10ml of a 10mg / ml MXene dispersion at room temperature. After sonication and oscillation for 30 minutes, an 8.5mg / ml MXene / silver nanoparticle dispersion was obtained. The silver nanowire dispersion and the MXene / silver nanoparticle dispersion were mixed in a volume ratio of 1:22 to obtain a 7.0mg / ml multidimensional conductive nanomaterial dispersion. The dispersion was centrifuged and dried in a vacuum at 50°C to obtain a multidimensional conductive powder.

[0064] The second step: adding polyester to N,N-dimethylformamide, stirring and dissolving at 40°C, and then adding multidimensional conductive powder, wherein the mass ratio of multidimensional conductive powder to polyester is 2:1, and fully stirring to obtain a wet spinning solution with a mass fraction of 15%; placing the spinning solution in a 20ml syringe, adjusting the extrusion speed of the wet spinning propulsion pump to 25ml / h, and using a 0.51mm syringe needle to uniformly extrude the spinning solution into a coagulation bath of deionized water and anhydrous ethanol (volume ratio of 7:3), with a drafting ratio of 3.5 times, so that the spinning solution is quickly formed in the coagulation bath, and then placed in a ventilated environment at room temperature to dry for 24h to obtain a wet-spun fiber with a diameter of 0.2mm.

[0065] The third step is to warp the wet-spun fibers to arrange them neatly, and then weave them on a digital loom using plain weave. The warp density is set to 12 yarns / cm and the weft density is set to 20 yarns / cm. The warp tension is dynamically adjusted according to the breakage rate and hairiness index during the weaving process to ensure the structural uniformity of the fabric during the weaving process, thereby producing a strain-sensing fabric.

[0066] The strain sensing fabric with health monitoring function is thus obtained. The warp and weft yarns are evenly arranged, and there are multi-level conductive coupling paths at the fiber level, so that the fabric can achieve conductive connectivity under high strain. The fabric thickness is 600μm, the elastic elongation is 80%, the sensitivity is 115 at this elongation, and the conductivity is 6500S / cm. It can identify the human body's pulse rate per minute, gestures, and running frequency to achieve non-destructive health monitoring. According to the national standard GB / T12704.2-2009 positive cup method test, the strain sensing fabric has a moisture permeability flux of 9000g / m2 / d, which is comfortable to wear.

[0067] Example 6

[0068] A method for preparing a strain sensing fabric with health monitoring function, comprising the following steps:

[0069] Step 1: For the synthesis of one-dimensional silver nanowires, first add 0.4g of polyvinyl pyrrolidone to 20ml of ethylene glycol and dissolve it at 40°C, add 0.2g of silver nitrate, place it in a flask in the dark and stir for 20min, then add 0.1ml of 0.1mol / L sodium chloride aqueous solution, heat the flask at 170°C for 2h, filter and wash the precipitate, and disperse it in ethanol to prepare a silver nanowire dispersion with a concentration of 7.5mg / ml; for the synthesis of two-dimensional MXene, add 3.0g of lithium fluoride to 40ml of 9mol / L dilute hydrochloric acid, and then add 1.0g of Ti3 AlC2 powder was magnetically stirred in an oil bath at 35°C for 24 hours at 200 rpm / min. The solution was then centrifuged at 5000 rpm for 5 minutes until the supernatant pH was >6. The precipitate was then placed in 50ml of ethanol and sonicated for 30 minutes to obtain a 10mg / ml MXene dispersion. For the synthesis of zero-dimensional silver nanoparticles, 2.5ml of a 2.5mg / ml silver nitrate solution was slowly added dropwise to 10ml of a 10mg / ml MXene dispersion at room temperature. After sonication and oscillation for 30 minutes, an 8.5mg / ml MXene / silver nanoparticle dispersion was obtained. The silver nanowire dispersion and the MXene / silver nanoparticle dispersion were mixed in a 1:2 volume ratio to obtain a 10.0mg / ml multidimensional conductive nanomaterial dispersion. The dispersion was centrifuged and dried in a vacuum at 50°C to obtain a multidimensional conductive powder.

[0070] The second step: adding polyacrylonitrile to N,N-dimethylformamide, stirring and dissolving at 40°C, and then adding multidimensional conductive powder, wherein the mass ratio of multidimensional conductive powder to polyacrylonitrile is 3:1, and stirring thoroughly to obtain a wet spinning solution with a mass fraction of 16%; placing the spinning solution in a 20ml syringe, adjusting the extrusion speed of the wet spinning propulsion pump to 30ml / h, and using a 0.51mm syringe needle to uniformly extrude the spinning solution into a coagulation bath of deionized water and anhydrous ethanol (volume ratio of 7:3), with a drafting ratio of 2.0 times, so that the spinning solution is quickly formed in the coagulation bath, and then placed in a ventilated environment at room temperature to dry for 24h to obtain a wet-spun fiber with a diameter of 0.3mm.

[0071] The third step is to warp the wet-spun fibers to arrange them neatly, and then weave them on a digital loom using plain weave. The warp density is set to 10 yarns / cm and the weft density is set to 23 yarns / cm. The warp tension is dynamically adjusted according to the breakage rate and hairiness index during the weaving process to ensure the structural uniformity of the fabric during the weaving process, thereby producing a strain-sensing fabric.

[0072] The strain sensing fabric with health monitoring function is thus obtained. The warp and weft yarns are evenly arranged, and there are multi-level conductive coupling paths at the fiber level, which enables the fabric to achieve conductive connectivity under high strain. The fabric thickness is 650μm, the elastic elongation is 70%, the sensitivity is 125 at this elongation, and the conductivity is 8000S / cm. It can identify the human body's pulse rate per minute, gestures, and running frequency, realizing non-destructive health monitoring. According to the national standard GB / T12704.2-2009 positive cup method test, the strain sensing fabric has a moisture permeability flux of 7000g / m2 / d, which is comfortable to wear.

[0073] Example 7

[0074] A method for preparing a strain sensing fabric with health monitoring function, comprising the following steps:

[0075] Step 1: For the synthesis of one-dimensional silver nanowires, first add 0.4g of polyvinyl pyrrolidone to 20ml of ethylene glycol and dissolve it at 40°C, add 0.1g of silver nitrate, place it in a flask in the dark and stir for 20min, then add 0.2ml of 0.1mol / L sodium chloride aqueous solution, heat the flask at 170°C for 2h, filter and wash the precipitate, and disperse it in ethanol to prepare a silver nanowire dispersion with a concentration of 7.0mg / ml; For the synthesis of two-dimensional MXene, add 3.0g of lithium fluoride to 40ml of 9mol / L dilute hydrochloric acid, and then add 1.5g of Ti3 AlC2 powder was magnetically stirred in an oil bath at 35°C for 24 hours at 200 rpm / min. The solution was then centrifuged at 5000 rpm for 5 minutes until the supernatant pH reached >6. The precipitate was then placed in 50ml of ethanol and sonicated for 30 minutes to obtain a 10mg / ml MXene dispersion. For the synthesis of zero-dimensional silver nanoparticles, 2.5ml of a 2.5mg / ml silver nitrate solution was slowly added dropwise to 10ml of a 10mg / ml MXene dispersion at room temperature. After sonication and oscillation for 30 minutes, an 8.5mg / ml MXene / silver nanoparticle dispersion was obtained. The silver nanowire dispersion and the MXene / silver nanoparticle dispersion were mixed in a 1:1 volume ratio to obtain an 8.0mg / ml multidimensional conductive nanomaterial dispersion. The dispersion was centrifuged and dried in a vacuum at 50°C to obtain a multidimensional conductive powder.

[0076] The second step: add polyacrylonitrile to N,N-dimethylformamide, stir and dissolve at 40°C, then add multidimensional conductive powder, wherein the mass ratio of multidimensional conductive powder to polyacrylonitrile is 2:1, and after sufficient stirring, a wet spinning solution with a mass fraction of 15% is obtained; the spinning solution is placed in a 20ml syringe, and the extrusion speed of the wet spinning propulsion pump is adjusted to 35ml / h. The spinning solution is uniformly extruded into a coagulation bath of deionized water and anhydrous ethanol (volume ratio of 7:3) using a 0.51mm syringe needle, and the drafting multiple is 2.5 times, so that the spinning solution is quickly formed in the coagulation bath, and then it is placed in a ventilated environment at room temperature to dry for 24 hours to obtain a wet-spun fiber with a diameter of 0.2mm.

[0077] The third step is to warp the wet-spun fibers to arrange them neatly, and then weave them on a digital loom using plain weave. The warp density is set to 11 yarns / cm and the weft density is set to 26 yarns / cm. The warp tension is dynamically adjusted according to the breakage rate and hairiness index during the weaving process to ensure the structural uniformity of the fabric during the weaving process, thereby producing a strain-sensing fabric.

[0078] The strain sensing fabric with health monitoring function is thus obtained. The warp and weft yarns are evenly arranged, and there are multi-level conductive coupling paths at the fiber level, so that the fabric can achieve conductive connectivity under high strain. The fabric thickness is 500μm, the elastic elongation is 75%, the sensitivity is 103 at this elongation, and the conductivity is 7200S / cm. It can identify the human body's pulse rate per minute, gestures, and running frequency to achieve non-destructive health monitoring. According to the national standard GB / T12704.2-2009 positive cup method test, the strain sensing fabric has a moisture permeability flux of 9500g / m2 / d, which is comfortable to wear.

[0079] The present invention and its embodiments are described above. This description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if a person skilled in the art is inspired by this and, without departing from the purpose of the present invention, designs structures and embodiments similar to this technical solution without inventiveness, they shall fall within the scope of protection of the present invention.

Claims

1. A method for preparing a strain sensing fabric with health monitoring function, characterized in that: The following steps are involved: Step 1: Synthesize one-dimensional silver nanowires using a polyol method, synthesize two-dimensional MXene nanosheets using a hydrochloric acid / lithium fluoride system, and add silver nitrate solution to the MXene dispersion for in-situ reduction to generate zero-dimensional silver nanoparticles. The three are mixed and stirred to produce a multidimensional conductive nanomaterial. Step 2: Adding a fiber-forming polymer to a solvent, then adding a multidimensional conductive nanomaterial, dissolving and stirring the solution to obtain a wet spinning solution; and using a wet spinning device to prepare a wet-spinning fiber with high elasticity and high conductivity. Step 3: After drying, the above fibers are used as warp and weft yarns, and spinning parameters such as warp tension are adjusted on a digital loom to weave a strain-sensing fabric with air and moisture permeability.

2. The method for preparing a strain sensing fabric with health monitoring function according to claim 1, characterized in that: The scale range of the multidimensional conductive nanomaterial described in step 2 is: The average diameter of zero-dimensional silver nanoparticles is 50 to 400 nm; The average diameter of one-dimensional silver nanowires is 50 to 400 nm; The microstructure of two-dimensional MXene nanosheets is accordion-shaped, with an average interlayer spacing of <200 nm.

3. The method for preparing a strain sensing fabric with health monitoring function according to claim 2, characterized in that: The average diameter of the wet-spun fiber in step 2 is 0.2 to 0.8 mm, and the diameter is adjustable.

4. The method for preparing a strain sensing fabric with health monitoring function according to claim 3, characterized in that: The strain sensing fabric with health monitoring function described in step 3 has a warp density of 6 to 12 threads / cm and a weft density of 15 to 30 threads / cm.

5. The method for preparing a strain sensing fabric with health monitoring function according to claim 4, characterized in that: The one-dimensional silver nanowires described in step 1 are synthesized by heating 0.2-0.4 g polyvinyl pyrrolidone, 0.1-0.3 g silver nitrate, and 10-30 ml ethylene glycol at 150-200° C. for 2 h to obtain silver nanowires with a certain aspect ratio, which are then dispersed in ethanol at a dispersion concentration of 0.5-10 mg / ml.

6. The method for preparing a strain sensing fabric with health monitoring function according to claim 5, characterized in that: The synthesis of zero-dimensional silver nanoparticles described in step 1 adopts an in-situ reduction method using MXene as a reducing agent. The concentration of silver nitrate is 1-5 mg / ml, and it is slowly dripped into the MXene dispersion. After 5-40 minutes of oscillation and ultrasonic treatment, the silver nanoparticles are evenly distributed on the surface of the MXene nanosheets.

7. The method for preparing a strain sensing fabric with health monitoring function according to claim 6, characterized in that: The wet spinning fiber-forming polymer described in step 2 is any one or a combination of thermoplastic polyurethane, polyethylene, polyacrylonitrile, polyester, polyvinyl alcohol, and polyamide. The solvent system used is one or more of N,N-dimethylformamide, dimethylacetamide, and tetrahydrofuran. The mass percentage of the spinning solution concentration is 7 to 20%. The coagulation bath uses any one or a combination of water, ethanol, and dimethyl sulfoxide. The spinneret diameter is 0.1 to 0.5 mm, the coagulation bath temperature is 20 to 50°C, the propulsion pump extrusion speed is 20 to 150 mm / s, and the drafting ratio is 2.0 to 4.5X.

8. The method for preparing a strain sensing fabric with health monitoring function according to claim 7, characterized in that: The strain sensing fabric described in step 3 is woven using a digital loom, and the warp tension is dynamically adjusted to reduce the breakage rate and hairiness index. The weaving breakage rate is less than 5%, and the hairiness index is ≤2.

0.

9. The method for preparing a strain sensing fabric with health monitoring function according to claim 8, characterized in that: The elastic elongation of the wet-spun fiber in step 2 is 80% to 300%, and the tensile strength at break is greater than 20 MPa. The elastic elongation of the strain sensing fabric is 30% to 160%, and the tensile strength at break is greater than 50 MPa.

10. The method for preparing a strain sensing fabric with health monitoring function according to claim 9, characterized in that: The wet-spun fiber sensitivity described in step 2 is greater than 100, the strain sensing fabric sensitivity is greater than 80, the electrical conductivity is greater than 5000 S / cm, and the moisture permeability is greater than 5100 g / m2 / d.

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