Air-permeable and water-repellent multi-stage structure multifunctional fabric and preparation method thereof
By using a multi-level structural design, a breathable and hydrophobic multifunctional fabric was developed to solve the sensing performance problem of flexible strain sensors in high humidity environments, achieving high sensitivity, wide response range and stability, making it suitable for wearable electronic devices.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZHENGZHOU UNIVERSITY OF AERONAUTICS
- Filing Date
- 2026-04-24
- Publication Date
- 2026-06-12
AI Technical Summary
Existing flexible strain sensors suffer from poor sensing performance in high humidity environments, making it difficult to balance high sensitivity and wide sensing response range.
A multi-level structural design, including micro-nano structures, porous structures, and microcrack structures, was adopted. By layer-by-layer impregnation with dopamine hydrochloride, carbon nanotubes, poly(3,4-ethylenedioxythiophene): polystyrene sulfonic acid, and perfluorodecyl mercaptan solution, a breathable and hydrophobic multifunctional fabric was prepared, forming a conductive polymer composite material-based strain sensor.
It improves the sensor's sensitivity and response range, ensures the sensor's stability and durability, and also has breathable, hydrophobic and electrothermal properties, making it suitable for long-term wear.
Smart Images
Figure CN122190031A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of lightweight flexible materials technology, specifically relating to a breathable and hydrophobic multi-level structured multifunctional fabric and its preparation method. Background Technology
[0002] Flexible wearable electronic devices are widely used in fields such as human physiological activity monitoring, health management, disease prevention, artificial skin, and human-computer interaction due to their ability to flexibly adhere to human skin and their superior sensing capabilities. Strain sensors are one of the core components of flexible wearable electronic devices. However, traditional metal or semiconductor-based strain sensors have limited deformation ranges and narrow measurement ranges, greatly restricting their application areas. Therefore, flexible strain sensors have emerged. Furthermore, wearable electronic devices are inevitably exposed to sweat, water, oil, and other substances during daily use. Under normal activity conditions, human skin continuously produces sweat, which evaporates into the external environment as water vapor. During motion monitoring, especially during performance evaluation, the wearer sweats profusely, and the exhaled air during respiratory monitoring creates a high-humidity environment, affecting the sensing performance of sensors in flexible wearable electronic devices.
[0003] Furthermore, existing conductive polymer composite materials possess advantages such as low cost, good processing performance, and tunable properties, and are often used as sensing materials for flexible sensors to appropriately improve their sensing performance. However, due to the viscoelasticity of polymer materials, conductive polymer composite-based flexible strain sensors face the challenge of balancing high sensitivity and a wide sensing response range. Summary of the Invention
[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a breathable and hydrophobic multi-level multifunctional fabric and its preparation method, which solves the problem of difficulty in coordinating high sensitivity and wide sensing response range in the above-mentioned conductive polymer composite material-based flexible strain sensors.
[0005] The present invention adopts the following technical solution: A breathable and hydrophobic multi-level multifunctional fabric is prepared by sequentially immersing an elastic fabric in a first mixed solution, a carbon nanotube dispersion, a second mixed solution, and a third solution.
[0006] Furthermore, the first mixed solution is a dopamine hydrochloride / tris(hydroxymethyl)aminomethane mixed solution, which is prepared by mixing dopamine hydrochloride and tris(hydroxymethyl)aminomethane buffer at a ratio of 2 mg: 1 mL.
[0007] Furthermore, the second mixed solution is a poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid / dimethyl sulfoxide mixed solution, wherein the mass ratio of dimethyl sulfoxide to poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid solution is 5:100; the addition of dimethyl sulfoxide solvent to poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid solution can improve the conductivity of poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid).
[0008] Furthermore, the third mixed solution is a 1H,1H,2H,2H-perfluorodecylthiol / anhydrous ethanol mixed solution, with a mass ratio of 1H,1H,2H,2H-perfluorodecylthiol to anhydrous ethanol of 0.03:100.
[0009] A method for preparing a breathable and hydrophobic multi-level structured multifunctional fabric includes the following steps: Dopamine hydrochloride was mixed with tris(hydroxymethyl)aminomethane buffer to obtain a dopamine hydrochloride / tris(hydroxymethyl)aminomethane mixed solution. The elastic fabric was immersed in a mixed solution of dopamine hydrochloride / tris(hydroxymethyl)aminomethane and dried to obtain a polydopamine-modified elastic fabric. The elastic fabric modified with polydopamine was immersed in a carbon nanotube dispersion, sonicated, and dried to obtain a conductive fabric coated with carbon nanotubes. A conductive fabric coated with carbon nanotubes was immersed in a mixed solution of poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid / dimethyl sulfoxide and dried to obtain a conductive fabric coated with PEDOT:PSS / CNT. PEDOT: A PSS / CNT coated conductive fabric is immersed in a mixed solution of 1H,1H,2H,2H-perfluorodecylthiol / anhydrous ethanol, stirred, and dried to obtain a multifunctional fabric.
[0010] Furthermore, the elastic fabric includes at least one of TPU fiber membrane fabric, polyurethane PU fiber membrane fabric, styrene-butadiene-styrene block copolymer SBS fiber membrane fabric, hydrogenated styrene-ethylene / butene-styrene block copolymer SEBS fiber membrane fabric, polyvinylidene fluoride PVDF fiber membrane fabric, polyacrylonitrile PAN fiber membrane fabric, spandex fabric, and cotton spandex fabric.
[0011] Furthermore, the ratio of tris(hydroxymethyl)aminomethane to water in the tris(hydroxymethyl)aminomethane buffer solution is 0.3 g: 100 mL.
[0012] Furthermore, the drying conditions are 58~62℃ for 20min~60min.
[0013] Furthermore, the concentration of the carbon nanotube dispersion is 0.3~8 mg / mL, and the solvent is deionized water; the carbon nanotubes include one of multi-walled carbon nanotubes, carboxylated multi-walled carbon nanotubes, hydroxylated multi-walled carbon nanotubes, and single-walled carbon nanotubes.
[0014] Furthermore, the preparation steps of the poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid solution / dimethyl sulfoxide mixed solution are as follows: Dimethyl sulfoxide was added to a poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid solution to obtain a poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid / dimethyl sulfoxide mixed solution, wherein the concentration of the poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid solution was 0.5 mg / mL to 3 mg / mL.
[0015] Furthermore, the ultrasound conditions are 800~1000W, 20min~30min.
[0016] Furthermore, the conductive fabric coated with PEDOT:PSS / CNT is immersed in a 1H,1H,2H,2H-perfluorodecylthiol solution and stirred for 60-70 minutes.
[0017] A conductive polymer composite material-based strain sensor is made of multifunctional fabric, conductive silver paste, and conductive cloth tape.
[0018] The principle of this invention: The multi-level structure designed in this invention, incorporating micro / nano structures, porous structures, and microcrack structures, exhibits significant effects in regulating strain sensing performance. The opening and closing of the outer microcrack structure under strain induces a significant change in resistance, thereby enhancing the sensor's sensitivity. Simultaneously, the porous structure of the elastic fabric serves as the framework for the inner conductive network structure, loading conductive nanomaterials. Even when the outer microcrack structure opens, it still acts as a bridge between the microcrack sheets, thus broadening the response range of the strain sensor.
[0019] Through this multi-level structure design, the sensitivity and response range of the strain sensor are significantly improved, while ensuring excellent stability and durability, resulting in superior overall strain sensing performance.
[0020] Meanwhile, by adjusting the pore size and porosity of the elastic fabric and introducing a hydrophobic coating on the surface of the conductive elastic fabric, the air permeability and hydrophobicity of the fabric-based strain sensor are ensured. The construction of a multi-level conductive network structure ensures good conductivity, thereby achieving excellent electrothermal performance.
[0021] Compared with the prior art, the present invention has the following beneficial effects: (1) This invention provides a breathable and hydrophobic multi-level multifunctional fabric, which is prepared by sequentially immersing an elastic fabric in a dopamine hydrochloride / tris(hydroxymethyl)aminomethane mixed solution, a carbon nanotube dispersion, a poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid / dimethyl sulfoxide mixed solution, and a 1H,1H,2H,2H-perfluorodecylthiol / anhydrous ethanol mixed solution. After the multifunctional fabric is fabricated into a sensor, the GF value is 1438.15 at 650% strain, and the response range is not lower than 650% strain.
[0022] (2) The present invention uses a layer-by-layer dip-coating process to prepare a fabric CPCs strain sensor with a multi-level structure, including micro-nano structure, porous structure and microcracks. The sensor has high sensitivity, wide response range, good stability and durability. The micro-scale system has a micro-nano structure formed by carbon nanotubes with high aspect ratio, a porous structure formed by TPU fiber overlap in the fiber membrane fabric, and a microcrack structure formed by the difference in modulus between the TPU fiber membrane substrate and the conductive coating.
[0023] (3) The multi-level structure sensor designed in this invention has multiple functions such as breathability, hydrophobicity and electrothermal response, which can meet the comfort of long-term wear and the practical application requirements, ensure the performance of strain sensor in low temperature climate, and broaden the practicality of wearable strain sensor. Attached Figure Description
[0024] Figure 1 In the image, a is a SEM image of the TPU fiber membrane fabric; b is a SEM image of the TPU fiber membrane fabric treated with PDA; c is a SEM image of the TPU fiber membrane fabric coated with CNTs; and d is a SEM image of the hydrophobic conductive fabric obtained after dip-coating with PEDOT:PSS and hydrophobic treatment. The red arrows mark the microcrack structures.
[0025] Figure 2 Electrical response signal graphs of CNT coated with conductive fabric (CT) and hydrophobic conductive fabric CPCs (PPCT) under strain; the vertical axis ∆R / R0 represents the relative resistance change; the horizontal axis Strain represents the tensile strain.
[0026] Figure 3 The graph shows the sensitivity of hydrophobic conductive fabric CPCs under tensile strain; the vertical axis ∆R / R0 represents the relative resistance change; the horizontal axis Strain represents the tensile strain.
[0027] Figure 4The bar chart shows the water vapor transmission rate of TPU fiber membrane fabric, hydrophobic conductive fabric CPCs, and open and sealed conditions. The vertical axis WVTR represents water vapor transmission rate; the horizontal axis Open represents the control group; TPU represents the TPU fiber membrane fabric group; PPCT represents the hydrophobic conductive fabric CPCs group; and Sealed represents the sealed plastic film group, covering bottles containing the same mass of deionized water.
[0028] Figure 5 The WCA of the PPCT conductive fiber membrane is shown at different stretching degrees; the vertical axis WCA represents the water droplet contact angle; the horizontal axis Strain represents the tensile strain.
[0029] Figure 6 The graph shows the change of surface temperature (Temperature) of PPCT conductive fabric under different voltages over time. Detailed Implementation
[0030] The present invention will be further described in detail below with reference to embodiments, but the embodiments of the present invention are not limited thereto. Unless otherwise specified, the technical means used in the following embodiments are conventional means well known to those skilled in the art; the experimental methods used are all conventional methods; the materials, reagents, etc. used are all commercially available products in the art or prepared by conventional methods in the art.
[0031] Poly(3,4-ethylenedioxythiophene): Polystyrene sulfonic acid (PEDOT): PSS, from Heraeus, product number Clevios™ PH 1000; Carbon nanotubes (CNTs), multi-walled carbon nanotubes, from Jiangsu Xianfeng Nanomaterials Technology Co., Ltd.; 1H,1H,2H,2H-perfluorodecyl mercaptan (PFDT); Dopamine hydrochloride (DA); Polydopamine (PDA); Dimethyl sulfoxide (DMSO); Thermoplastic polyurethane elastomer (TPU), from BASF, product number Elastollan 1185A; Hydrophobic conductive fabrics (CPCs) (PPCT).
[0032] Example 1 The preparation steps of a breathable and hydrophobic multi-level structured multifunctional fabric are as follows: S1. Electrospinning to prepare elastic fabrics Weigh 4g of TPU particles and add them to 40mL of a 1:1 dimethylformamide / tetrahydrofuran mixture to prepare an electrospinning solution with a TPU mass fraction of 10%. Stir for 4 hours.
[0033] 7 mL of electrospinning solution was drawn using a 10 mL syringe and placed in an electrospinning machine, with release paper fixed to the roller. The feed speed was 2 mL / min, the roller speed was 200 rpm / min, the distance between the needle and the roller was 12 cm, the spinning voltage was 12 kV, the needle movement distance was 20 cm, the humidity was maintained at 35%, and the temperature was maintained at 30℃ during spinning.
[0034] After electrospinning is completed, the TPU fiber membrane along with the release paper is removed and placed in a 60℃ drying oven for 12 hours to obtain TPU elastic fabric. The release paper is A4 size, and the electrospun fiber membrane is spun on the release paper. The electrospinning yields an A4-sized TPU fabric, which is then cut into 20mm×5mm pieces during subsequent preparation.
[0035] Observe using a scanning electron microscope (SEM), such as Figure 1 As shown in a, the TPU elastic fabric fibers have a smooth surface, and the fibers overlap to form a three-dimensional porous network skeleton.
[0036] S2, Polydopamine pretreatment: First, 0.6 g of Tris was dissolved in 200 mL of deionized water to obtain a Tris buffer solution with a pH of 8.5. Then, 0.4 g of dopamine hydrochloride was dissolved in the Tris buffer solution and stirred for 10 min to ensure complete dissolution. Next, the TPU elastic fabric was immersed in the DA / Tris buffer solution and stirred at 25 °C for 6 hours. During this process, dopamine polymerized on the surface of the TPU fiber membrane fabric to form a polydopamine PDA layer. After 6 hours, the TPU fiber membrane fabric was removed, and the unpolymerized dopamine monomers were washed with deionized water. Subsequently, it was dried in an oven at 60 °C for 60 min to obtain the polydopamine-modified elastic fabric.
[0037] Observe using a scanning electron microscope (SEM), such as Figure 1 As shown in b, the surface of the elastic fabric modified with polydopamine becomes rough, but the three-dimensional porous network skeleton of the fiber membrane fabric is not destroyed, and the adhesion of PDA helps the conductive filler to form a stable and uniform conductive layer on the fiber surface of the fiber membrane fabric during the dip coating process.
[0038] S3. Apply CNT coating: The elastic fabric modified with polydopamine was immersed in 50 mL of CNT conductive dispersion for 30 min. The concentration of the CNT conductive dispersion was 2 mg / mL. During the process, an ultrasonic cleaner was used to help the CNTs penetrate into the fabric. The ultrasonic cleaner was used at 800 W for 30 min. After the immersion coating was completed, the fabric was rinsed with deionized water to remove the unattached CNTs on the fabric surface. The fabric was then dried in an oven at 60 °C for 20 min to obtain the carbon nanotube coated conductive fabric, i.e., the CNT coated conductive fabric.
[0039] Observe using a scanning electron microscope (SEM), such as Figure 1 As shown in c, the fiber surface is coated with CNTs with a high aspect ratio.
[0040] S4. Coating PEDOT: PSS layer: Next, a 2 mg / mL PEDOT:PSS solution was prepared and 5 wt% DMSO was added. The TPU fiber membrane fabric coated with CNTs was immersed in the solution for 30 min and then dried to obtain PEDOT:PSS / CNT coated conductive fabric.
[0041] Observe using a scanning electron microscope (SEM), such as Figure 1 As shown in d, the conductive fiber surface is coated with a PEDOT:PSS layer, and there are microcrack structures on the surface of the PEDOT:PSS layer. At the same time, the three-dimensional porous network skeleton of the TPU fiber membrane fabric is still well maintained and has not been damaged.
[0042] Figure 1 In micrometer-scale systems, there are micro / nano structures formed by high aspect ratio carbon nanotubes, porous structures formed by overlapping TPU fibers in fibrous membrane fabrics, and microcrack structures formed due to the difference in modulus between the TPU fiber membrane substrate and the conductive coating. Porous structures refer to the porous structures formed by overlapping TPU fibers in fibrous membrane fabrics, such as... Figure 1 As shown in d, microcrack structures can be seen on the TPU fibers.
[0043] S5. Hydrophobic treatment: The PEDOT:PSS / CNT coated conductive fabric obtained in the previous step is immersed in an anhydrous ethanol solution of 0.03wt%PFDT and stirred for 60 min; then dried at 60℃ for 60 min to obtain PFDT-treated hydrophobic conductive fabric CPCs, i.e., multifunctional fabric.
[0044] PFDT provides a hydrophobic surface coating by forming a self-assembled monolayer, improving wettability and reducing surface energy, thus creating a robust hydrophobic layer on the surface of the elastic conductive fiber. This not only improves the performance and reliability of the elastic conductive fiber but also extends its service life.
[0045] Example 2 The preparation steps of a breathable and hydrophobic multi-level structured multifunctional fabric are as follows: S1. Electrospinning to prepare elastic fabrics Weigh 4g of TPU particles and add them to 40mL of a 1:1 dimethylformamide / tetrahydrofuran mixture to prepare an electrospinning solution with a TPU mass fraction of 10%. Stir for 4 hours.
[0046] 7 mL of electrospinning solution was drawn using a 10 mL syringe and placed in an electrospinning machine, with release paper fixed to the roller. The feed speed was 2 mL / min, the roller speed was 200 rpm / min, the distance between the needle and the roller was 12 cm, the spinning voltage was 12 kV, the needle movement distance was 20 cm, and the humidity was maintained at 35 ± 3% RH and the temperature was maintained at 30 ± 5℃ during spinning.
[0047] After electrospinning is completed, the TPU fiber film and release paper are removed together and placed in a drying oven at 60℃ for 12 hours to obtain TPU elastic fabric.
[0048] S2, Polydopamine pretreatment: First, 0.6 g of Tris was dissolved in 200 mL of deionized water to obtain a Tris buffer solution with a pH of 8.5. Then, 0.4 g of dopamine hydrochloride was dissolved in the Tris buffer solution and stirred for 10 min to ensure complete dissolution. Next, the TPU elastic fabric was immersed in the DA / Tris buffer solution and stirred at 25 °C for 6 h. During this process, dopamine polymerized on the surface of the TPU fiber membrane fabric to form a polydopamine PDA layer. After 6 h, the TPU fiber membrane fabric was removed, and the unpolymerized dopamine monomers were washed with deionized water. Subsequently, it was dried in an oven at 58 °C for 60 min to obtain the polydopamine-modified elastic fabric.
[0049] S3. Apply CNT coating: The polydopamine-modified elastic fabric was immersed in 50 mL of CNT conductive dispersion for 30 min. The concentration of the CNT conductive dispersion was 0.3 mg / mL. During the process, an ultrasonic cleaner was used to help the CNTs penetrate into the fabric. The ultrasonic cleaner was used at 1000 W for 20 min. After the immersion coating was completed, the fabric was rinsed with deionized water to remove the unattached CNTs on the fabric surface and dried in an oven at 62 °C for 20 min to obtain the carbon nanotube-coated conductive fabric.
[0050] S4. Coating PEDOT: PSS layer: Next, a 0.5 mg / mL PEDOT:PSS solution was prepared and 5 wt% DMSO was added. The TPU fiber membrane fabric coated with CNTs was immersed in the solution for 30 min and then dried to obtain PEDOT:PSS / CNT coated conductive fabric.
[0051] S5. Hydrophobic treatment: The PEDOT:PSS / CNT coated conductive fabric obtained in the previous step is immersed in an anhydrous ethanol solution of 0.03wt%PFDT and stirred for 60 min; then dried at 60℃ for 60 min to obtain PFDT-treated hydrophobic conductive fabric CPCs, i.e., multifunctional fabric.
[0052] Example 3 The preparation steps of a breathable and hydrophobic multi-level structured multifunctional fabric are as follows: S1. Electrospinning to prepare elastic fabrics Weigh 4g of TPU particles and add them to 40mL of a 1:1 dimethylformamide / tetrahydrofuran mixture to prepare an electrospinning solution with a TPU mass fraction of 10%. Stir for 4 hours.
[0053] 7 mL of electrospinning solution was drawn using a 10 mL syringe and placed in an electrospinning machine, with release paper fixed to the roller. The feed speed was 2 mL / min, the roller speed was 200 rpm / min, the distance between the needle and the roller was 12 cm, the spinning voltage was 12 kV, the needle movement distance was 20 cm, and the humidity was maintained at 35 ± 3% RH and the temperature was maintained at 30 ± 5℃ during spinning.
[0054] After electrospinning is completed, the TPU fiber film and release paper are removed together and placed in a drying oven at 60℃ for 12 hours to obtain TPU elastic fabric.
[0055] S2, Polydopamine pretreatment: First, 0.6 g of Tris was dissolved in 200 mL of deionized water to obtain a Tris buffer solution with a pH of 8.5. Then, 0.4 g of dopamine hydrochloride was dissolved in the Tris buffer solution and stirred for 10 min to ensure complete dissolution. Next, the TPU elastic fabric was immersed in the DA / Tris buffer solution and stirred at 25 °C for 6 h. During this process, dopamine polymerized on the surface of the TPU fiber membrane fabric to form a polydopamine PDA layer. After 6 h, the TPU fiber membrane fabric was removed, and the unpolymerized dopamine monomers were washed with deionized water. Subsequently, it was dried in an oven at 58 °C for 60 min to obtain the polydopamine-modified elastic fabric.
[0056] S3. Apply CNT coating: The elastic fabric modified with polydopamine was immersed in 50 mL of CNT conductive dispersion for 30 min. The concentration of the CNT conductive dispersion was 8 mg / mL. During the process, an ultrasonic cleaner was used to help the CNTs penetrate into the fabric. The ultrasonic cleaner was used at 1000 W for 20 min. After the immersion coating was completed, the fabric was rinsed with deionized water to remove the unattached CNTs on the fabric surface and dried in an oven at 62 °C for 20 min to obtain the carbon nanotube coated conductive fabric.
[0057] S4. Coating PEDOT: PSS layer: Next, a 3 mg / mL PEDOT:PSS solution was prepared and 5 wt% DMSO was added. The TPU fiber membrane fabric coated with CNTs was immersed in the solution for 30 min and then dried to obtain PEDOT:PSS / CNT coated conductive fabric.
[0058] S5. Hydrophobic treatment: The PEDOT:PSS / CNT coated conductive fabric obtained in the previous step is immersed in an anhydrous ethanol solution of 0.03wt%PFDT and stirred for 60 min; then dried at 60℃ for 60 min to obtain PFDT-treated hydrophobic conductive fabric CPCs, i.e., multifunctional fabric.
[0059] In both Examples 2 and 3, carbon nanotube-coated conductive fabrics show carbon nanotubes distributed on the fiber surface, only the loading amount is different.
[0060] Application Example 1 The multifunctional fabric prepared in Example 1 was coated with conductive silver paste at both ends and then introduced into a conductive fabric tape as electrodes to prepare a conductive polymer composite-based strain sensor. Strain sensing performance and electrothermal performance were then tested.
[0061] Experiment 1: Strain Sensing Performance Test The strain sensing performance was tested by applying tensile strain to the sensor using a universal testing machine, while a high-precision digital multimeter was used to collect and record the resistance change of the sensor in real time during the tensile process.
[0062] like Figure 2 As shown, the GF value of CNT-coated conductive fabric at 650% strain is only 325.32, while the GF value of hydrophobic conductive fabric CPCs at 650% strain is 1438.15. The comparison demonstrates that the hydrophobic conductive fabric significantly improves sensitivity while maintaining a well-preserved response range, which is not lower than 650% strain.
[0063] After further fitting, such as Figure 3 As shown, the sensitivity of hydrophobic conductive fabric CPCs increases with increasing strain. The GF values for strain ranges of 0%~100%, 100%~200%, 200%~400%, 400%~600%, and 600%~650% are 6.03, 32.65, 240.69, 2212.39, and 8433.41, respectively.
[0064] Experiment 2: Air permeability test Bottles containing the same mass of deionized water were covered using the TPU elastic fabric (TPU), hydrophobic conductive fabric CPCs (PPCT), and a sealing plastic film (Sealed) as described in Example 1 to measure the water vapor transmission rate (WVTR). An open bottle containing the same mass of deionized water was used as a control group. All bottles were placed in an oven at 60°C and 40% relative humidity, and the remaining water volume was measured every two hours. Figure 4 As shown, the WVTR value of the open bottle is 2.5 kg / (m³). 2 The WVTR values of TPU fiber membrane fabrics and hydrophobic conductive fabric CPCs were 2.3 kg / (m²). 2 ·d) and 2.2kg / (m 2 ·d), which shows that TPU fiber membrane fabric has good breathability, and the breathability of hydrophobic conductive fabric CPCs is also well maintained.
[0065] Experiment 3 Hydrophobicity Test The hydrophobic conductive fabrics (CPCs) and PPCTs in Example 1 were tested using a microscopic optical contact angle meter; the water droplet contact angle (WCA) under different tensile strains was measured. During the test, 5 μL of deionized water was placed on the sample surface and allowed to stand for 10 seconds to ensure the droplet was stable. Figure 5 As shown, the contact angle of the hydrophobic conductive fabric CPCs is 116º, and the contact angle at 210% strain is 113º, indicating that the hydrophobicity is well maintained.
[0066] Experiment 4 Electrothermal Performance Test Different voltages are applied to the sensor using a DC power supply, and a multi-channel temperature meter is used to collect and record the temperature changes of the sensor in real time while the voltage is applied.
[0067] like Figure 6 As shown, when the voltage increases from 0.1V to 1V, the average temperature of PPCT increases from 25.6℃ to 98.2℃, indicating that PPCT conductive fabric has excellent electrothermal performance.
[0068] The above descriptions are merely embodiments of the present invention, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.
Claims
1. A breathable and hydrophobic multi-level structured multifunctional fabric, characterized in that, The multifunctional fabric is prepared by sequentially immersing an elastic fabric in a first mixed solution, a carbon nanotube dispersion, a second mixed solution, and a third solution. The first mixed solution is a dopamine hydrochloride / tris(hydroxymethyl)aminomethane mixed solution, which is prepared by mixing dopamine hydrochloride and tris(hydroxymethyl)aminomethane buffer at a ratio of 2 mg: 1 mL; The second mixed solution is a poly(3,4-ethylenedioxythiophene): polystyrene sulfonic acid / dimethyl sulfoxide mixed solution, wherein the mass ratio of dimethyl sulfoxide to poly(3,4-ethylenedioxythiophene): polystyrene sulfonic acid solution is 5:100; The third mixed solution is a 1H,1H,2H,2H-perfluorodecylthiol / anhydrous ethanol mixed solution, with a mass ratio of 1H,1H,2H,2H-perfluorodecylthiol to anhydrous ethanol of 0.03:
100.
2. A method for preparing a breathable and hydrophobic multi-level structured multifunctional fabric, characterized in that, Includes the following steps: Dopamine hydrochloride was mixed with tris(hydroxymethyl)aminomethane buffer to obtain a dopamine hydrochloride / tris(hydroxymethyl)aminomethane mixed solution. The elastic fabric was immersed in a mixed solution of dopamine hydrochloride / tris(hydroxymethyl)aminomethane and dried to obtain a polydopamine-modified elastic fabric. Polydopamine-modified elastic fabric was immersed in carbon nanotube dispersion, sonicated, and dried to obtain carbon nanotube-coated conductive fabric. A conductive fabric coated with carbon nanotubes was immersed in a mixed solution of poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid / dimethyl sulfoxide and dried to obtain a conductive fabric coated with PEDOT:PSS / CNT. PEDOT: A PSS / CNT coated conductive fabric is immersed in a mixed solution of 1H,1H,2H,2H-perfluorodecylthiol / anhydrous ethanol, stirred, and dried to obtain a multifunctional fabric.
3. The preparation method according to claim 2, characterized in that, The elastic fabric includes at least one of TPU fiber membrane fabric, polyurethane PU fiber membrane fabric, styrene-butadiene-styrene block copolymer SBS fiber membrane fabric, hydrogenated styrene-ethylene / butene-styrene block copolymer SEBS fiber membrane fabric, polyvinylidene fluoride PVDF fiber membrane fabric, polyacrylonitrile PAN fiber membrane fabric, spandex fabric, and cotton spandex fabric.
4. The preparation method according to claim 2, characterized in that, The ratio of tris(hydroxymethyl)aminomethane to water in the tris(hydroxymethyl)aminomethane buffer solution is 0.3 g: 100 mL.
5. The preparation method according to claim 2, characterized in that, The drying conditions are 58~62℃ for 20min~60min.
6. The preparation method according to claim 2, characterized in that, The concentration of the carbon nanotube dispersion is 0.3~8 mg / mL, and the solvent is deionized water; the carbon nanotubes include one of multi-walled carbon nanotubes, carboxylated multi-walled carbon nanotubes, hydroxylated multi-walled carbon nanotubes, and single-walled carbon nanotubes.
7. The preparation method according to claim 2, characterized in that, The preparation steps for the poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid solution / dimethyl sulfoxide mixed solution are as follows: Dimethyl sulfoxide was added to a poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid solution to obtain a poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid / dimethyl sulfoxide mixed solution, wherein the concentration of the poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid solution was 0.5 mg / mL to 3 mg / mL.
8. The preparation method according to claim 2, characterized in that, The ultrasound conditions are 800~1000W, 20min~30min.
9. The preparation method according to claim 2, characterized in that, The PEDOT:PSS / CNT coated conductive fabric is immersed in a mixed solution of 1H,1H,2H,2H-perfluorodecylthiol / anhydrous ethanol and stirred for 60-70 minutes.
10. A strain sensor based on a conductive polymer composite material, characterized in that, It is made from the multifunctional fabric, conductive silver paste and conductive cloth tape as described in claim 1.