CN115418860A - Conductive fiber body, preparation method thereof and application thereof in preparing strain sensor - Google Patents
Conductive fiber body, preparation method thereof and application thereof in preparing strain sensor Download PDFInfo
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- A61B5/02—Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
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- D06M11/74—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising with carbon or compounds thereof with carbon or graphite; with carbides; with graphitic acids or their salts
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Abstract
The invention belongs to the field of flexible wearability, and particularly relates to a conductive fibrous body, a preparation method thereof and application thereof in preparing a strain sensor. A conductive fibrous body comprises a matrix core material, a microsphere/fiber framework layer and a graphene conductive layer which are sequentially arranged from inside to outside. Use of a conductive fibrous body in the manufacture of a strain sensor. The strain sensor prepared by adopting the conductive fibrous body has extremely high sensitivity, wide strain range, quick response time and good durability, and the high sensitivity under micro strain meets the requirement of micro deformation monitoring, such as health detection of human body pulse beat, throat vibration and the like. Meanwhile, the sensor can be used for monitoring violent and large-amplitude movement, such as joint movement. The invention has simple preparation process and controllable structure, can be integrated into yarn or fabric through weaving and sewing, and has huge application prospect in flexible wearable sensors.
Description
Technical Field
The invention belongs to the field of flexible wearability, and particularly relates to a conductive fibrous body, a preparation method thereof and application thereof in preparing a strain sensor.
Background
In recent years, the application of flexible strain sensors to intelligent wearable devices has attracted great attention of researchers, and the flexible strain sensors can capture and evaluate human body movement and health conditions in real time and show great application potential and market value. The traditional semiconductor and metal foil strain gauge has the defects of strong rigidity, low sensitivity, narrow sensing range (5%) and the like, so that the application of the strain gauge in the field of intelligent wearable is limited. However, in the new materials, graphene has the characteristics of lightness, thinness, transparency, excellent conductivity and mechanical properties and the like, and has extremely important and wide application prospects in the aspect of sensing technologies.
The conductive fiber has the characteristics of light weight, softness, capability of weaving and the like, can bear various deformations such as bending, torsion, stretching and the like, endows the fiber-based sensor with the capability of adapting to the wearing performance of a human body and skin, and has good reliability when used for monitoring physiological signals of the human body. A commonly used preparation method of the fiber-based flexible sensor is to uniformly disperse a conductive material in a molten or dissolved flexible matrix, and the conductive material/flexible matrix homogeneous composite fiber can be prepared by various spinning methods, and the method has the advantages of simple operation, low cost, easy large-scale production and the like, but the prepared sensor is not sensitive to small strain, has slow response speed and poor tensile property (epsilon is less than 30%). Another method is to cover or infiltrate conductive material into the surface of the fiber to construct a conductive network to prepare the strain sensor. The interface action of the conductive material and the fiber matrix has an important influence on the performance of the sensor, and the sensitivity of the graphene-based fiber sensor prepared usually is generally low (GF 0.1-30) in the strain range of 0-10%, so that the improvement of the sensitivity of the graphene-based fiber sensor in the small strain range is a great challenge.
Disclosure of Invention
The invention mainly overcomes the defects of the prior art, and provides a conductive fibrous body and a preparation method thereof, wherein the number of contact points of a graphene conductive network is increased through structural design, so that the sensitivity is improved. The invention discloses a fiber strain sensor with good elasticity, wide strain range and high sensitivity, which is prepared based on a chestnut-rod-shaped lead fiber body structure modified by hollow microspheres and the mechanical flexibility and the electrical conductivity of graphene.
In order to solve the technical problems, the invention adopts the following technical scheme:
a conductive fiber body comprises a matrix core material, a microsphere/fiber framework layer and a graphene conductive layer which are sequentially arranged from inside to outside.
Preferably, the matrix core material is made of any one of polyurethane elastic fiber, polyether ester elastic fiber, polyolefin elastic fiber and elastic polyester fiber, the microsphere/fiber framework layer is constructed by expanded microspheres, and the graphene conductive layer is made of graphene oxide.
A method for producing the above-mentioned one conductive fiber body, comprising the steps of:
step S1, preparing an expanded microsphere/elastic polymer finishing liquid: weighing a certain amount of elastic polymer, adding expanded microspheres, and uniformly dispersing to obtain an expanded microsphere/elastic polymer finishing liquid; wherein, the elastic polymer is as follows by mass: expanded microspheres =1:3% -10%;
s2, soaking the one-dimensional elastomer in the expanded microsphere/elastic polymer finishing liquid, and then sequentially heating, rinsing and drying to obtain an intermediate;
s3, soaking the intermediate in graphene finishing liquid, drying, soaking in the graphene finishing liquid, drying, circulating for multiple times, and performing chemical reduction treatment to obtain a conductive fiber body;
furthermore, in S1, the foaming temperature of the expanded microspheres is 80-120 ℃, and the particle size is 5-10 μm.
In S1, the elastic polymer is any one of aqueous polyurethane, polyvinyl alcohol, and polyacrylate aqueous solution.
In S2, the one-dimensional elastomer is any one of polyurethane elastic fiber, polyether ester elastic fiber, polyolefin elastic fiber, and elastic polyester fiber.
Furthermore, in S2, the time condition of dipping is 5-10min, the temperature condition of heating is 80-120 ℃, and the time condition is 10-30min.
Further, in S3, the graphene finishing liquid is a graphene oxide aqueous solution, the solid content of the graphene oxide aqueous solution is 5-10mg/mL, the dipping time condition in S3 is 5-10min, and the cycle number is 1-5 times.
The conductive fibrous body is applied to the preparation of a strain sensor.
The preparation method of the strain sensor comprises the steps of connecting two ends of the conductive fiber body with copper wires by using conductive silver paste, and connecting the conductive fiber body with an external power supply after the conductive silver paste is solidified, so as to obtain the strain sensor. The technical scheme provided by the invention has the beneficial effects that:
(1) The elastic structure and the continuous corrugated graphene conductive network of the three-dimensional chestnut-rice-stick-shaped fiber skeleton designed by the invention can provide more conductive contact points for stress-strain sensing, have larger deformation space and provide a foundation for certain tensile strain;
(2) The framework structure designed by the invention generates huge microstructure change and conductive network change when strain occurs, the sensor can be endowed with extremely high sensitivity and quick response capability even under extremely small strain, and the sensor has excellent cycling stability and wide strain range due to the elastic recovery performance of the graphene reinforced microsphere/fiber framework;
(3) Strain sensor based on this structure preparation possesses the function of real-time supervision health status and motion, can realize beating human pulse, throat vibration and the detection of each human joint motion state, has very big application potentiality in the aspect of intelligent wearable equipment such as virtual reality, human-computer interaction, health monitoring.
Description of the drawings:
FIG. 1 is an SEM photograph of a polyurethane elastic fiber in example 1 of the present invention;
FIG. 2 is an SEM picture of the fiber modified by the expanded beads in example 1 of the present invention;
fig. 3 is an SEM picture of a graphene oxide-modified microsphere/fiber scaffold in example 1 of the present invention;
fig. 4 is an SEM picture of a reduced graphene oxide modified microsphere/fiber scaffold in example 1 of the present invention;
FIG. 5 shows the strain range and sensitivity of the strain sensor manufactured in example 1 of the present invention under uniaxial tension;
FIG. 6 is a response time test of a strain sensor prepared in example 1 of the present invention at 0-6% strain;
FIG. 7 shows 2000 cycles of stability testing at 0-20% strain for a strain sensor made in accordance with example 1 of the present invention;
FIG. 8 is a diagram showing the results of the strain sensor according to example 1 of the present invention for detecting the knee movement of a human body;
fig. 9 is a result of detecting the throat working condition of a human body by using the strain sensor manufactured in embodiment 1 of the present invention;
fig. 10 shows the result of detecting the pulse vibration of a human body by using the strain sensor manufactured in example 1 of the present invention.
The specific implementation scheme is as follows:
the invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.
The conductive fibrous body is of a chestnut-rice-stick-shaped structure and comprises a base core material, a microsphere/fiber framework layer and a graphene conductive layer which are sequentially arranged from inside to outside. Specifically, the invention adopts a one-dimensional elastomer as a matrix core material, a surface microstructure is constructed by expanded microspheres to form a microsphere/fiber framework layer, and a graphene conductive network is used as a shell to be modified on a micro-convex spherical surface of the graphene conductive network to wrap the framework and fill gaps among the microspheres, so that the chestnut-rod-shaped core-spun fiber structure is prepared.
According to the invention, the 'chestnut-rice-rod' -shaped conductive fibrous body is applied to the preparation of the strain sensor, when the prepared sensor is subjected to deformation such as stretching, bending, twisting and folding under the action of external force, the relative resistance change is caused by the change of the conductive network structure based on the deformation of the expanded microspheres, the flattening of the wrinkled graphene and the expansion of microcracks, and the deformation of the material is detected and indicated by detecting the relative resistance change. In addition, the elastic structure of the three-dimensional chestnut-rice-rod-shaped fiber skeleton and the continuous corrugated graphene conductive network can provide more conductive contact points for stress-strain sensing, have larger deformation space and provide a foundation for the tensile strain of the sensor.
The working mechanism of the strain sensor is as follows:
(1) Under the condition of low strain, when external strain is applied, the sensor is stretched by virtue of the inherent excellent elasticity of the substrate and the hollow microspheres, the microspheres in close contact are gradually pulled apart to generate displacement, and the contact resistance is increased;
(2) Along with the increase of strain, the graphene conducting layer on the outer layer is gradually flattened from a corrugated shape along the direction parallel to the stress direction, the contact points of the graphene conducting network on the outer layer of the adjacent microsphere are reduced, the conducting path is reduced, and the contact resistance is sharply increased;
(3) At very high strains, the sensor expands further and the conductive network develops microcracks, resulting in a further increase in the relative change in resistance. When the strain is released, due to the excellent elastic recovery performance of the framework, the expanded sensor can be recovered to the original state, the microcracks are gradually closed, the graphene layer is recovered to the folded state, and the microspheres are recovered to the dense arrangement, so that the change of the relative resistance of the sensor is reduced and the initial value is recovered. The deformation of the material is detected by detecting the relative resistance change.
In addition, the invention also provides a preparation method of the strain sensor, which mainly comprises the following steps:
step S1, preparing an expanded microsphere/elastic polymer finishing liquid: weighing a certain amount of elastic polymer, adding expanded microspheres, and uniformly dispersing to obtain an expanded microsphere/elastic polymer finishing liquid; wherein, the elastic polymer is as follows by mass: expanded microspheres =1:3% -10%; the foaming temperature of the expanded microspheres is 80-120 ℃, the particle size is 5-10 mu m, and the elastic polymer is any one of aqueous polyurethane, polyvinyl alcohol and polyacrylate water solution;
s2, soaking the one-dimensional elastomer in an expanded microsphere/elastic polymer finishing liquid for 5-10min, heating in a drying oven at 80-120 ℃ for 10-30min, heating a low-boiling-point core material in the expanded microsphere to generate pressure to cause microsphere volume expansion, constructing an expanded microsphere modified chestnut-rice-rod-shaped fiber framework with a core-shell structure, rinsing with deionized water, and drying in air to obtain an intermediate; wherein the one-dimensional elastomer is any one of polyurethane elastic fiber, polyether ester elastic fiber, polyolefin elastic fiber and elastic polyester fiber, the soaking time is 5-10min, the heating temperature is 80-120 ℃, and the heating time is 10-30min; the preparation method does not limit the dosage of the one-dimensional elastomer, and can adopt a one-dimensional elastomer material with a corresponding length according to actual needs;
s3, soaking the intermediate in graphene finishing liquid for 5-10min, drying in a 50 ℃ drying oven, soaking in the graphene finishing liquid for 5-10min, drying in the 50 ℃ drying oven, circulating the step for 1-5 times, and performing chemical reduction treatment to obtain a conductive fiber body; the method comprises the following steps of (1) realizing a raised spherical microstructure modified by a multi-layer graphene coating through the self-assembly combination effect of graphene and an intermediate to obtain a chestnut-rice-rod-shaped fibrous body; wherein the graphene finishing liquid is a graphene oxide aqueous solution, the solid content of the graphene oxide aqueous solution is 5-10mg/mL, and the impregnation time is 5-10min; removing oxygen-containing functional groups on the surface of the graphene oxide by chemical reduction reaction, recovering a pi-pi conjugated structure, enhancing the strength and conductivity of the matrix, and obtaining a chestnut-rod-shaped conductive fibrous body with the reduced graphene oxide as a conductive carrier;
and S4, connecting two ends of the conductive fiber body with copper wires by using conductive silver paste, and connecting the conductive fiber body with an external power supply after the conductive silver paste is solidified to obtain the strain sensor.
In the preparation method, the expanded microspheres and the conductive silver paste are purchased from the market, wherein the model of the expanded microspheres is F-48 (Nippon Songban grease pharmaceutical Co., ltd.), and the model of the conductive silver paste is 3812 (Shenzhen Xinwei electronic materials Co., ltd.).
< example 1>
A method for preparing a strain sensor comprises the following steps:
step S1, preparing an expanded microsphere/elastic polymer finishing liquid: weighing 50g of waterborne polyurethane, adding 2.5g of expanded microspheres, and dispersing by using a homogenizer to obtain uniformly dispersed expanded microsphere/polyurethane finishing liquid;
s2, soaking polyurethane elastic fibers (shown in figure 1) in the expanded microsphere/polyurethane finishing liquid prepared in the step S1 for 10min, placing the soaked polyurethane elastic fibers in an oven at the temperature of 120 ℃, heating the soaked polyurethane elastic fibers for 10min, heating and foaming the polyurethane elastic fibers to construct a fiber framework (shown in figure 2) modified by the expanded microspheres with the core-shell structure, rinsing the fiber framework with deionized water, and drying the fiber framework in the air to obtain an intermediate;
s3, soaking the intermediate in graphene finishing liquid with solid content of 5mg/mL for 10min, drying in a 50-DEG C drying oven, soaking in the graphene finishing liquid, repeating for 5 times in a circulating manner to realize a multi-layer graphene coating-modified convex spherical microstructure (as shown in figure 3), and performing chemical reduction through ascorbic acid solution to obtain a reduced graphene oxide coating-loaded chestnut rod-shaped conductive fibrous body (as shown in figure 4);
and S4, coating conductive silver paste at two ends of the chestnut-rice-stick-shaped conductive fiber body prepared in the step S3 to be used as electrodes, and attaching copper wires and the conductive silver paste and fixing the copper wires and the conductive silver paste by using a conductive copper foil adhesive tape to prepare the strain sensor.
The strain sensor prepared by the invention is respectively tested for tensile property test, human motion detection, human health monitoring and the like, and the specific operation is as follows:
(1) And (3) testing tensile property: the strain sensor prepared in this example generates strain by unidirectionally stretching a sample with a TC-DLJ-PC microcomputer controlled testing machine, and tests resistance change conditions and performance stability under cyclic stretching under different stretching strains with a DM3068 digital multimeter, and the test results are shown in fig. 5-7. Wherein, the sensor is stretched from the initial length to the required length and then is restored to the initial length in one stretching cycle.
As can be seen from FIG. 5, the sensor has a wide strain detection range of 0-100%, and the relative resistance change rate increases with the increase of strain. The sensitivity factor is 118.24 at 0.5% -20% strain, 331.32 at 20% -80% strain, and 904.77 at 80% -100% strain. The sensor has a wide strain range, can detect the motion state of a human body, has a relative resistance change rate of 57.75% under 0.5% weak tensile deformation, and provides possibility for detecting weak signal change.
As can be seen from fig. 6, the response time of the sensor is 87.4ms, and the quick response is undoubtedly helpful for monitoring the health index of the human body in real time.
Figure 7 shows that the performance stability under cyclic stretching, the resistance change of the sensor remains around 2180% after 2000 stretch-release cycles, indicating that the sensor has excellent cyclic stability performance in terms of strain response, providing potential for further practical application of the sensor.
(2) Human motion detection: the strain sensor prepared in this example was attached to the knee to monitor and identify the movements of the knee joint such as jogging, sprinting and jumping, and the test results are shown in fig. 8. As can be seen from fig. 8, when the knee joint is bent, the resistance of the sensor starts to increase correspondingly, which has excellent repeatable responsiveness to the movement of the knee joint, and the peak value and the width of the curve are different in different movement states. Similarly, the sensor can identify the motion state of the human body according to various response curves.
(3) Monitoring the human health: the strain sensor prepared in this example was attached to the neck of a human body to monitor throat vibration, and the test results are shown in fig. 9. As can be seen from fig. 9, when the human body performs swallowing and coughing actions, the sensor will show corresponding response curves, the peaks and widths of which are different. The sensor is fixed on the wrist to monitor the human pulse, and the test result is shown in fig. 10. As can be seen from fig. 10, the strain sensor prepared in this embodiment can clearly detect the heart rate physiological signals of the human body, and the inset shows the characteristic peak of typical human body pulse waveforms corresponding to the shock wave (P wave), the tidal wave (T wave), and the diastolic wave (D wave). The result shows that the strain sensor prepared by the embodiment can be used for monitoring human body pulse beating, throat vibration and other fine human body motions, and further can realize real-time monitoring on various health conditions of a human body. Indicating that it has important and diverse potential in wearable electronics, health monitoring and smart robots.
< example 2>
A method for preparing a strain sensor comprises the following steps:
step S1, preparing an expanded microsphere/elastic polymer finishing liquid: weighing 50g of polyvinyl alcohol, adding 1.5g of expanded microspheres, and dispersing by a homogenizer to obtain uniformly dispersed expanded microsphere/polyvinyl alcohol finishing liquid;
s2, soaking polyurethane elastic fibers in the expanded microsphere/polyvinyl alcohol finishing liquid prepared in the step S1 for 5min, placing the soaked polyurethane elastic fibers in an oven at the temperature of 120 ℃ for heating for 10min, heating and foaming the soaked polyurethane elastic fibers to construct a fiber framework modified by the expanded microspheres with the core-shell structure, rinsing the fiber framework with deionized water, and drying the fiber framework in the air to obtain an intermediate;
s3, soaking the intermediate in graphene oxide finishing liquid with the solid content of 8mg/mL for 10min, drying the intermediate in a 50-DEG C drying oven, soaking the intermediate in the graphene finishing liquid, repeating the steps for 5 times in a circulating manner to realize a raised spherical microstructure modified by a multi-layer graphene coating, and chemically reducing the raised spherical microstructure by using an ascorbic acid solution to obtain a chestnut rod-shaped conductive fibrous body loaded by the reduced graphene oxide coating;
and S4, coating conductive silver paste at two ends of the chestnut-rice-stick-shaped conductive fiber body prepared in the step S3 to be used as electrodes, and attaching copper wires and the conductive silver paste and fixing the copper wires and the conductive silver paste by using a conductive copper foil adhesive tape to prepare the strain sensor.
< example 3>
A method for preparing a strain sensor comprises the following steps:
step S1, preparing an expanded microsphere/elastic polymer finishing liquid: weighing 50g of waterborne polyurethane, adding 5g of expanded microspheres, and dispersing by using a homogenizer to obtain uniformly dispersed expanded microsphere/polyurethane finishing liquid;
s2, soaking the polyolefin elastic fiber in the expanded microsphere/polyurethane finishing liquid prepared in the step S1 for 10min, placing the soaked polyolefin elastic fiber in an oven at the temperature of 100 ℃ for heating for 10min, heating and foaming the soaked polyolefin elastic fiber to construct a fiber framework modified by the expanded microsphere with the core-shell structure, rinsing the fiber framework with deionized water, and drying the fiber framework in the air for later use to obtain an intermediate;
s3, soaking the intermediate in 10mg/mL graphene oxide finishing liquid for 10min, drying the intermediate in a 50 ℃ drying oven, soaking the intermediate in the graphene finishing liquid, repeating the steps for 5 times in a circulating manner to realize a raised spherical microstructure modified by a multi-layer graphene coating, and chemically reducing the raised spherical microstructure by using an ascorbic acid solution to obtain a chestnut rod-shaped conductive fibrous body loaded by the reduced graphene oxide coating;
and S4, coating conductive silver paste at two ends of the chestnut-rice-stick-shaped conductive fiber body prepared in the step S3 to be used as electrodes, and attaching copper wires and the conductive silver paste and fixing the copper wires and the conductive silver paste by using a conductive copper foil adhesive tape to prepare the strain sensor.
< comparative example 1>
S1, soaking polyurethane elastic fibers in 5mg/mL graphene oxide finishing liquid for 10min, drying in a 50-DEG C drying oven, soaking in the graphene finishing liquid, and repeating for 5 times in a circulating mode to achieve a multi-layer graphene coating modified fiber structure.
And S2, chemically reducing the fiber structure prepared in the S1 by using an ascorbic acid solution to obtain the conductive fiber loaded with the reduced graphene oxide coating.
And S3, coating conductive silver paste at two ends of the conductive fiber prepared in the step S2 to be used as electrodes, and attaching the copper wire and the conductive silver paste and fixing the copper wire and the conductive silver paste by using a conductive copper foil adhesive tape to prepare the strain sensor.
The strain sensor prepared in the embodiment is tested for tensile property, and the strain sensor has a wide strain detection range of 0-100%, and the relative resistance change rate is increased along with the increase of strain. However, the sensitivity factor is 25.43 at 0-65% strain and 64.58 at 65% -100% strain.
Compared with example 1, the elastic fiber strain sensor prepared in comparative example 1 has lower sensitivity because the change of the relative resistance is only related to the expansion and closing of the microcracks during the strain process, and the structural change and the change of the conductive network are not obvious, so the sensor is not sensitive to the stimulation under small strain.
The specific raw materials listed in the invention, the upper and lower limits of the raw materials and the process parameters and the values of the intervals can realize the invention, and the examples are not listed. The features of the embodiments and embodiments described herein above may be combined with each other without conflict.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (10)
1. The conductive fiber body is characterized by comprising a matrix core material, a microsphere/fiber framework layer and a graphene conductive layer which are sequentially arranged from inside to outside.
2. The conductive fiber body of claim 1, wherein the matrix core material is made of any one of polyurethane elastic fiber, polyether ester elastic fiber, polyolefin elastic fiber, and elastic polyester fiber, the microsphere/fiber skeleton layer is constructed by expanded microspheres, and the graphene conductive layer is made of graphene oxide.
3. A method for producing an electrically conductive fibrous body according to claim 1 or 2, comprising the steps of:
step S1, preparing an expanded microsphere/elastic polymer finishing liquid: weighing a certain amount of elastic polymer, adding expanded microspheres, and uniformly dispersing to obtain an expanded microsphere/elastic polymer finishing liquid; wherein, the elastic polymer is as follows by mass: expanded microspheres =1:3% -10%;
s2, soaking the one-dimensional elastomer in the expanded microsphere/elastic polymer finishing liquid, and then sequentially heating, rinsing and drying to obtain an intermediate;
and S3, soaking the intermediate in the graphene finishing liquid, drying, soaking in the graphene finishing liquid, drying, circulating for multiple times, and performing chemical reduction treatment to obtain the conductive fiber body.
4. The method for producing a conductive fibrous body according to claim 3, wherein in S1, the expanded microspheres have a foaming temperature of 80 to 120 ℃ and a particle diameter of 5 to 10 μm.
5. The method of claim 3, wherein in S1, the elastic polymer is any one of aqueous polyurethane, polyvinyl alcohol, and polyacrylate solution.
6. The method of claim 3, wherein in S2, the one-dimensional elastomer is any one of polyurethane elastic fiber, polyether ester elastic fiber, polyolefin elastic fiber, and elastic polyester fiber.
7. The method for preparing an electrically conductive fiber according to claim 3, wherein the dipping time in S2 is 5 to 10min, the heating temperature is 80 to 120 ℃ and the heating time is 10 to 30min.
8. The method for preparing a conductive fibrous body according to claim 3, wherein in S3, the graphene finishing liquid is an aqueous solution of graphene oxide, the solid content of the graphene finishing liquid is 5-10mg/mL, and in S3, the dipping time is 5-10min, and the cycle number is 1-5.
9. Use of a conductive fibrous body according to claim 1 or 2 in the manufacture of a strain sensor.
10. The method for manufacturing the strain sensor according to claim 9, wherein the two ends of the conductive fibrous body according to claim 1 or 2 are connected to copper wires by using conductive silver paste, and after curing, the conductive fibrous body is connected to an external power supply, thereby manufacturing the strain sensor.
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| CN107881768A (en) * | 2017-11-29 | 2018-04-06 | 合肥工业大学 | A kind of stretchable strain transducer based on polyurethane fiber and preparation method thereof |
| US20200255981A1 (en) * | 2017-05-31 | 2020-08-13 | South China University Of Technology | High-stretchable high-sensitive flexible force-sensitive sensing fiber and preparation method therefor |
| WO2022089510A1 (en) * | 2020-11-02 | 2022-05-05 | 香港理工大学 | Tensile conductive yarn and manufacturing method therefor |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US20200255981A1 (en) * | 2017-05-31 | 2020-08-13 | South China University Of Technology | High-stretchable high-sensitive flexible force-sensitive sensing fiber and preparation method therefor |
| CN107881768A (en) * | 2017-11-29 | 2018-04-06 | 合肥工业大学 | A kind of stretchable strain transducer based on polyurethane fiber and preparation method thereof |
| WO2022089510A1 (en) * | 2020-11-02 | 2022-05-05 | 香港理工大学 | Tensile conductive yarn and manufacturing method therefor |
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