A multi-electrode frictional power generation fiber and a preparation method and application thereof

Abstract

The application discloses a kind of multi-electrode friction power generation fibers and preparation method and application thereof, adopt friction disc false twister to the false twist of multiple copper wires, friction disc false twister includes by the friction disc shaft made of insulating material and is respectively arranged on the friction disc shaft and by upper and lower sequentially arranged first friction disc, second friction disc with material quality are carbon fiber;Spun modified polyvinyl alcohol fiber and make it adhere to first friction disc, spun SEBS fiber and make it adhere to second friction disc;In the false twist process, multiple copper wires rub with first friction disc, second friction disc in succession, and form the inner layer covered by modified polyvinyl alcohol fiber, outer layer covered by SEBS fiber in succession on the surface of multiple copper wires;The power generation fiber of the application can have good charge carrying capacity, good flexibility, good elasticity, good biocompatibility and power supply capacity, etc., is suitable for preparing deformation sensor.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of functional fibers, in particular to a multi-electrode frictional power generation fiber and a preparation method and application thereof. BACKGROUND

[0002] With the development of science and technology, intelligent wearable devices have shown great development prospects. The human body is an important source of energy, and the friction generated by people during exercise can realize energy conversion, can power wearable electronic devices, meet energy consumption needs, and thus break the dependence on external batteries. Deformation sensors play a crucial role in flexible wearable electronic devices. Fiber-based sensors have soft characteristics and can be woven into textiles or integrated on any shape, so fiber sensors have become the ideal choice for the next generation of electronic products for monitoring complex human activities.

[0003] However, the current flexible fiber electrode still has some deficiencies in the application process, such as insufficient voltage load capacity, poor flexibility, poor elasticity, or insufficient power supply performance, etc.

[0004] For example, patent document CN 111996641B proposes a triboelectric yarn composed of a thermoplastic elastomer skin layer and an embedded yarn, the oriented nanofiber layer of the embedded yarn is a soluble polymer, and the core layer is a conductive fiber, which uses metal wire or carbon fiber as the conductive fiber; patent document CN 101339820B discloses a preparation method of an optical fiber, which is made of a preform rod made of an organic polymer, the preform rod has a central hole for inserting a light guide fiber, and one or more through holes for passing metal wires, and the preform rod is heated and stretched to draw out a fiber wrapped with the light guide fiber and the metal wire. The core layer electrode of them has poor elasticity and has not been subjected to elastic treatment, and the yarn stretching has certain limitations.

[0005] For example, patent document CN 110227208A proposes a flexible fiber electrode prepared by taking a flexible filament conductive material as a core layer and polyether ether ketone as a coating layer after heat stretching; patent document CN 111277167A discloses a liquid electrode-polymer composite fiber, and the single electrode structure thereof has certain limitations for voltage load capacity.

[0006] For example, patent document CN 108180927B discloses a full-flexible self-powered sensor, which includes a liquid metal electrode layer, a piezoelectric material layer and a packaging layer, and its preparation process is complex, and the liquid metal has a risk of leakage, which has a biological compatibility hazard. At the same time, the resistivity of the liquid metal is higher than that of copper wire, and the conductive performance is not good, which affects the energy supply effect. SUMMARY

[0007] The application aims to overcome one or more deficiencies in the prior art and provide a novel preparation method of a multi-electrode triboelectric fiber, which has good charge carrying capacity, good flexibility, good elasticity, good biocompatibility and strong power supply capacity.

[0008] The application also provides the multi-electrode triboelectric fiber prepared by the method and application of the multi-electrode triboelectric fiber in preparing a deformation sensor.

[0009] To achieve the above-mentioned purposes, the application adopts a technical solution that is:

[0010] The application provides a preparation method of a multi-electrode triboelectric fiber.

[0011] The multi-electrode triboelectric fiber is prepared by the method, and the preparation method comprises the following steps:

[0012] The modified polyvinyl alcohol fiber is spun by the first electrostatic spinning mechanism and adhered to the first friction disc, and the SEBS fiber is spun by the second electrostatic spinning mechanism and adhered to the second friction disc.

[0013] In the false twisting process, the plurality of copper wires first rub against the first friction disc and then rub against the second friction disc, and a double-layer coating structure with an inner layer and an outer layer is formed on the surface of the plurality of copper wires in sequence, the inner layer is formed by the modified polyvinyl alcohol fiber, and the outer layer is formed by the SEBS fiber.

[0014] The modified polyvinyl alcohol fiber is spun by polyvinyl alcohol spinning solution containing silver powder.

[0015] According to some preferred aspects of the application, the diameter of a single copper wire is controlled to be less than 0.5 mm, the number of copper wires is 2-8, and the total diameter of the plurality of copper wires is less than 3 mm.

[0016] Further, the diameter of a single copper wire is controlled to be 0.01-0.15 mm.

[0017] Further, the total diameter of the plurality of copper wires is controlled to be 0.15-0.65 mm.

[0018] Further, the number of copper wires can be 2, 3, 4, 5, 6, 7, 8, 9 or 10.

[0019] According to some specific and preferred aspects of the present application, during the preparation process, the prepared multi-electrode triboelectric fiber is allowed to be grounded. The carbon fiber has certain conductivity, and the friction disc is in contact with the copper wire, so when the prepared multi-electrode triboelectric fiber is allowed to be grounded, it is equivalent to the grounding of the friction disc, which facilitates the collection of the spun fiber on the friction disc by electrostatic traction during the electrospinning process, and the conductivity of the carbon fiber is not as good as that of the copper wire, so that the copper wire can receive the fiber on the friction disc again during the rotation of the friction disc, so that the electrospun fiber is transferred through the friction disc and then loaded on the surface of the copper wire.

[0020] According to some preferred aspects of the present application, during the false twisting process, the draw ratio is 1.110-1.115, the ratio of the surface speed of each friction disc to the speed of the yarn leaving the friction disc false twister is 1.65-1.80, the speed of the yarn leaving the friction disc false twister is 450-650 m / h, and the ratio of the twisting tension T1 to the untwisting tension T2 is 0.75-0.85, and the rotation speed of each friction disc is independently 150-200 r / min.

[0021] According to some preferred aspects of the present application, in the polyvinyl alcohol spinning solution containing silver powder, the mass content of silver powder is 0.04-0.12 g / mL, and the mass concentration of polyvinyl alcohol is 14%-20%.

[0022] According to some preferred aspects of the present application, the molecular weight of the polyvinyl alcohol is 50000-180000, preferably 80000-140000.

[0023] In some embodiments of the present application, the preparation method of the polyvinyl alcohol spinning solution containing silver powder comprises:

[0024] A certain amount of dimethyl sulfoxide (DMSO) is added to a container, and then a certain amount of polyvinyl alcohol (PVA) is weighed and added to the container. The container is placed in a water bath machine, and heated and stirred at 80-95℃ (the time can be 30-120 min) to prepare a PVA solution with a concentration of 14%-20%. Then, a proper amount of silver powder is added to the PVA solution to make the concentration of silver powder in the PVA solution 0.04-0.12 g / mL, and the mixture is stirred and ultrasonically oscillated.

[0025] According to some preferred aspects of the present application, the SEBS fiber is prepared by spinning the SEBS spinning solution, and the SEBS spinning solution is obtained by dispersing SEBS in cyclohexane, and the mass concentration of SEBS in the SEBS spinning solution is 10%-20%.

[0026] In some embodiments of the present application, the preparation method of the SEBS spinning solution comprises:

[0027] A certain amount of hydrogenated styrene-butadiene block copolymer (SEBS) is added to cyclohexane and stirred until completely dissolved, then placed in a water bath for ultrasonic treatment to remove bubbles in the spinning solution, and a SEBS spinning solution with a mass concentration of 10%-20% is prepared.

[0028] According to some preferred aspects of the present application, the distance between the spinning nozzle of the first electrospinning mechanism and the first friction disc and the distance between the spinning nozzle of the second electrospinning mechanism and the second friction disc are both 5-10 cm.

[0029] According to some preferred aspects of the present application, during the spinning of the modified polyvinyl alcohol fiber, the flow rate of the polyvinyl alcohol spinning solution containing silver powder is 0.1-0.3 mL / h.

[0030] During the spinning of the SEBS fiber, the SEBS spinning solution is spun to form the SEBS fiber, and the flow rate of the SEBS spinning solution is 0.6-0.8 mL / h.

[0031] The present application provides another technical solution: a multi-electrode triboelectric fiber prepared by the preparation method of the multi-electrode triboelectric fiber.

[0032] The present application provides another technical solution: the application of the multi-electrode triboelectric fiber in preparing a deformation sensor.

[0033] Due to the use of the above technical solutions, the present application has the following advantages compared with the prior art:

[0034] First, the new multi-electrode triboelectric fiber prepared by the present application has an SEBS shell and a plurality of copper wire electrodes in the core layer. The SEBS has excellent rheological properties, which is more in line with human movement, thereby better monitoring human activity. Meanwhile, the SEBS can generate a larger voltage output by rubbing with the copper wire, and the excellent electrical conductivity of the copper wire electrode can well collect the triboelectric charge.

[0035] Second, the multi-electrode structure provided by the present application can make the triboelectric fiber have good charge carrying capacity, which can meet the power supply of intelligent wearable devices.

[0036] When charges are generated in the triboelectric fiber, they will be transmitted and accumulated through the conductive path of the copper wire. More copper wire numbers mean more conductive paths, which enable the charges to propagate more effectively in the fiber. At the same time, the increase in the number of copper wires will lead to an increase in the contact area of the triboelectric fiber. A larger contact area can provide more friction surfaces, increasing the generation and transmission area of the charges, thereby possibly improving the triboelectric performance. The increase in the number of roots will also lead to the enhancement of the electrical conductivity of the triboelectric fiber; better electrical conductivity helps the transmission and accumulation of charges, thereby enhancing the triboelectric performance.

[0037] More copper wire also results in better structural stability. During use and stress loading, the fibers are better able to maintain their shape and structural integrity, thus helping to maintain the stability of triboelectric properties.

[0038] Third, this invention creatively combines a friction disc false twister with an electrospinning device. On the one hand, the friction disc false twister is used to false twist multiple thin copper wires to make them have better cohesion. On the other hand, this invention can also coat the surface of multiple copper wires with modified polyvinyl alcohol fiber containing silver powder and SEBS successively during the false twisting process, so that the overall structure not only has excellent toughness, but also good tensile properties and excellent weaving effect.

[0039] Fourth, the polyvinyl alcohol (PVA) selected in this invention contains a large number of hydroxyl functional groups, which can form hydrogen bonds with the current collector (PVA can achieve adhesion to the metal by physical adsorption or chemical bonding with the metal surface through its hydroxyl functional groups, and it can form hydrogen bonds with oxygen atoms or other highly electronegative atoms on the metal surface), thereby obtaining good adhesion. This results in better adhesion and coating effect between the outer SEBS fiber layer and the inner copper wire electrode. In addition, the excellent biocompatibility of PVA makes it more suitable for wearable devices. Furthermore, the addition of silver powder can better improve the charge conduction capability.

[0040] Fifth, the multi-electrode triboelectric fiber of this invention can record mechanical motion through the triboelectric effect and electrostatic induction principle, and convert the mechanical energy generated by the movement of various parts of the human body into electrical energy. Its excellent elasticity and conductivity make it suitable for use in multifunctional wearable systems and smart textiles. Attached Figure Description

[0041] Figure 1 This is a schematic diagram illustrating the cooperation relationship between the friction disc false twister and the electrospinning equipment in an embodiment of the present invention;

[0042] Figure 2 This is a schematic diagram of the internal multiple electrodes in the multi-electrode triboelectric fiber prepared according to an embodiment of the present invention;

[0043] Figure 3 This is a schematic diagram of the triboelectric performance testing process in an embodiment of the present invention;

[0044] In the attached figures, the following are the reference numerals: 1. Multiple copper wires; 2. Friction disc false twister; 21. Friction disc shaft; 22. First friction disc; 23. Second friction disc; 31. First electrospinning nozzle; 32. Second electrospinning nozzle; 4. First electrospinning injector; 5. Polyvinyl alcohol spinning solution containing silver powder; 6. SEBS spinning solution; 7. Internal electrode with 4 copper wires; 8. Internal electrode with 6 copper wires; 9. Internal electrode with 8 copper wires; 10. First friction material; 11. Second friction material; 12. Multi-electrode triboelectric fiber. Detailed Implementation

[0045] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0046] See Figures 1 to 2 As shown, this embodiment of the invention provides a method for preparing multi-electrode triboelectric fibers and the resulting multi-electrode triboelectric fibers, the specific process of which includes:

[0047] Preparation of polyvinyl alcohol spinning solution containing silver powder: Add dimethyl sulfoxide (DMSO) to a container, then weigh a certain amount of polyvinyl alcohol (PVA, molecular weight 50,000-180,000, preferably 80,000-140,000) and add it to the container. Place the container in a water bath and heat and stir it in a water bath at 80-95℃ (for 30-120 minutes) to prepare a PVA solution with a concentration of 14%-20%. Then add an appropriate amount of silver powder to the PVA solution so that the concentration of silver powder in the PVA solution is 0.04-0.12 g / mL. Stir and ultrasonically vibrate to obtain a polyvinyl alcohol spinning solution containing silver powder.

[0048] Preparation of SEBS spinning solution: Add a certain amount of hydrogenated styrene-butadiene block copolymer (SEBS) to cyclohexane and stir until completely dissolved. Then place it in a constant temperature water bath at 15-40℃ and sonicate for 5-20 minutes to remove air bubbles in the spinning solution to obtain a SEBS spinning solution with a mass concentration of 10%-20%.

[0049] like Figure 1As shown, the production process employs a combination of a friction disc false twister 2, a first electrospinning mechanism, and a second electrospinning mechanism. The friction disc false twister 2 includes a friction disc shaft 21 made of insulating material and a first friction disc 22 and a second friction disc 23 respectively arranged on the friction disc shaft 21 from top to bottom. Both the first friction disc 22 and the second friction disc 23 are made of carbon fiber. Of course, only two friction discs for receiving the filament bundle are exemplarily shown. In fact, the structure of the friction disc false twister 2 used in this embodiment is an existing structure. The present invention only makes the following changes to the structure: First, the material of the friction disc shaft 21 is changed to a friction disc shaft made of insulating material to avoid affecting the collection of the spun filament bundle by the friction disc; Second, the material of the friction disc is changed to carbon fiber, which has lower conductivity than copper wire but can still conduct electricity.

[0050] The first electrospinning mechanism includes a first electrospinning injector 4 and a first electrospinning nozzle 31 connected to the first electrospinning injector 4. The first electrospinning injector 4 is filled with polyvinyl alcohol spinning solution containing silver powder. The first electrospinning nozzle 31 is directly opposite the first friction disc, and the distance between the two is 5-10 cm. The inner diameter of the first electrospinning nozzle 31 is 0.2 mm and the outer diameter is 0.3 mm.

[0051] The second electrospinning mechanism includes a second electrospinning injector and a second electrospinning nozzle 32 connected to the second electrospinning injector. The second electrospinning injector is filled with SEBS spinning solution 6. The second electrospinning nozzle 32 is directly opposite the second friction disc, and the distance between the two is 5-10 cm. The inner diameter of the second electrospinning nozzle 32 is 0.6 mm and the outer diameter is 0.7 mm.

[0052] Modified polyvinyl alcohol fibers are spun through the first electrospinning mechanism and attached to the first friction disk 22. The spinning voltage is 10-20 kV and the flow rate is 0.1-0.3 mL / h.

[0053] SEBS fibers are spun through a second electrospinning mechanism and attached to the second friction disk 23. The spinning voltage is 10-20 kV and the flow rate is 0.6-0.8 mL / h.

[0054] During the false twisting process, multiple copper wires 1 first rub against the first friction disc 22, and then rub against the second friction disc 23, forming a double-layer coating structure with an inner layer and an outer layer on the surface of the multiple copper wires 1. The inner layer is formed by coating with modified polyvinyl alcohol fiber, and the outer layer is formed by coating with SEBS fiber to obtain an intermediate. Then, after being treated in a hot box, a multi-electrode triboelectric fiber is made, and the prepared multi-electrode triboelectric fiber can be grounded.

[0055] On the one hand, due to friction, the filaments attached to the friction disk will be scraped by the copper wire to achieve adhesion; on the other hand, carbon fiber has a certain conductivity, and when the friction disk is in contact with the copper wire, the prepared multi-electrode triboelectric fiber can be grounded, which is equivalent to the friction disk being grounded. During the electrospinning process, it is convenient to collect the spun fibers on the friction disk through electrostatic traction. At the same time, the conductivity of carbon fiber is not as good as that of copper wire. During the rotation of the friction disk, the copper wire can receive the fibers on the friction disk again, so that the electrospun filaments are transferred through the friction disk and then loaded on the surface of the copper wire.

[0056] During the false twisting process, the stretch ratio is 1.110-1.115, the ratio of the surface velocity of each friction disc to the velocity of the filament leaving the friction disc false twister is 1.65-1.80, the velocity of the filament leaving the friction disc false twister is 450-650 m / h, the ratio of the twisting tension T1 to the untwisting tension T2 is 0.75-0.85, and the rotational speed of each friction disc is independently 150-200 r / min;

[0057] The temperature of the hot box is 240-330℃.

[0058] like Figure 2 As shown, exemplary schematic diagrams of the copper wire arrangements of internal electrodes 7 with 4 copper wires, internal electrodes 8 with 6 copper wires, and internal electrodes 9 with 8 copper wires are provided.

[0059] The above-mentioned solution will be further described below with reference to specific embodiments; it should be understood that these embodiments are used to illustrate the basic principles, main features and advantages of the present invention, and the present invention is not limited to the scope of the following embodiments; the implementation conditions used in the embodiments can be further adjusted according to specific requirements, and the implementation conditions not specified are usually the conditions in conventional experiments.

[0060] Unless otherwise specified in the following examples, all raw materials are commercially available or prepared by conventional methods in the art.

[0061] Example 1:

[0062] This example provides a method for preparing multi-electrode triboelectric fibers and the resulting multi-electrode triboelectric fibers, using the above-mentioned... Figure 1 The diagram shows the connection structure and process between the friction disc false twister and the electrospinning equipment, specifically:

[0063] Preparation of polyvinyl alcohol (PVA) solution: Preparation of polyvinyl alcohol spinning solution containing silver powder: Add dimethyl sulfoxide (DMSO) to a container, then weigh a certain amount of polyvinyl alcohol (PVA, Mw=125000) and add it to the container. Place the container in a water bath and heat and stir at 92℃ for 45 minutes to prepare a 14% PVA solution. Then add an appropriate amount of high-purity silver powder to the PVA solution to make the concentration of silver powder in the PVA solution 0.04 g / mL. Stir for 2 hours and ultrasonically vibrate for 5 minutes to obtain a polyvinyl alcohol spinning solution containing silver powder.

[0064] Preparation of SEBS solution: A certain amount of SEBS (purchased from Sinopec Baling Petrochemical Co., Ltd., brand name YH-688) was added to a cyclohexane solution and stirred until completely dissolved. The solution was then placed in a 20 ℃ constant temperature water bath and sonicated for 10 min to remove air bubbles from the spinning solution, thus obtaining a 15% SEBS spinning solution.

[0065] The number of copper wires is 4, and the diameter of the copper wires is 0.3mm. During the false twisting process, the process parameters are as follows: the speed at which the wire leaves the friction disc false twister is 650m / h, the rotation speed of the friction disc is 200 r / min, the stretch ratio is 1.110, the ratio of the surface speed of the friction disc to the speed at which the wire leaves the false twister is 1.65, the ratio of the twisting tension T1 to the untwisting tension T2 is 0.75, and the temperature of the hot box is 260℃.

[0066] The first electrospinning nozzle of the first electrospinning mechanism has an inner diameter of 0.2 mm and an outer diameter of 0.3 mm. The spinning voltage is 15 kV. The distance between the first electrospinning nozzle and the first friction disc is 5 cm. The flow rate of the polyvinyl alcohol spinning solution containing silver powder is 0.2 mL / h.

[0067] The inner diameter of the second electrospinning nozzle of the second electrospinning mechanism is 0.6 mm, the outer diameter is 0.7 mm, the spinning voltage is 15 kV, the distance between the second electrospinning nozzle and the second friction disc is 5 cm, and the flow rate of the SEBS spinning solution is 0.7 mL / h.

[0068] The viscosity of the obtained modified polyvinyl alcohol fiber is 10.21 Pa·s.

[0069] The triboelectric properties of the multi-electrode triboelectric fiber prepared in this embodiment were tested using a compression platform. A schematic diagram of the testing process is shown below. Figure 3As shown, the test includes a first friction material 10 and a second friction material 11. The second friction material 11 is fixed and used to hold the multi-electrode triboelectric fiber 12. The first friction material 10 can be moved vertically. By applying different pressures, the multi-electrode triboelectric fiber 12 is subjected to different effects, and its triboelectric properties are observed. Both the first friction material 10 and the second friction material 11 are made of acrylic sheets. The applied pressure is 0~20N. The contact length between the friction material and the multi-electrode triboelectric fiber 12 is 5cm, and the initial distance between the friction material and the fiber is 2cm. The test results are shown in Table 1.

[0070]

[0071] As shown in Table 1, the greater the pressure, the greater the current and voltage generated, which indicates that the fiber prepared by this invention has good self-powered performance.

[0072] Example 2:

[0073] This example provides a method for preparing multi-electrode triboelectric fibers and the resulting multi-electrode triboelectric fibers, which are basically the same as in Example 1, except that:

[0074] Heat and stir in a water bath for 55 minutes to prepare a 16% PVA solution. Then add an appropriate amount of high-purity silver powder to the PVA solution to make the concentration of silver powder in the PVA solution 0.08 g / mL.

[0075] The number of copper wires is 6, and the diameter of the copper wires is 0.3mm. During the false twisting process, the process parameters are as follows: the speed at which the wire leaves the friction disc false twister is 650m / h, the rotation speed of the friction disc is 175r / min, the stretch ratio is 1.112, the ratio of the surface speed of the friction disc to the speed at which the wire leaves the false twister is 1.7, the ratio of the twisting tension T1 to the untwisting tension T2 is 0.8, and the temperature of the hot box is 280℃.

[0076] The viscosity of the obtained modified polyvinyl alcohol fiber is 19.22 Pa·s.

[0077] The triboelectric properties of the multi-electrode triboelectric fiber prepared in this embodiment were tested using the same method as in Example 1, and the test results are shown in Table 2.

[0078]

[0079] Example 3:

[0080] This example provides a method for preparing multi-electrode triboelectric fibers and the resulting multi-electrode triboelectric fibers, which are basically the same as in Example 1, except that:

[0081] Heat and stir in a water bath for 65 minutes to prepare a PVA solution with a concentration of 18%. Then add an appropriate amount of high-purity silver powder to the PVA solution to make the concentration of silver powder in the PVA solution 0.12 g / mL.

[0082] The number of copper wires is 8, and the diameter of the copper wires is 0.3mm. During the false twisting process, the process parameters are as follows: the speed at which the wire leaves the friction disc false twister is 550m / h, the rotation speed of the friction disc is 150r / min, the stretch ratio is 1.112, the ratio of the surface speed of the friction disc to the speed at which the wire leaves the false twister is 1.7, the ratio of the twisting tension T1 to the untwisting tension T2 is 0.8, and the temperature of the hot box is 320℃.

[0083] The distance between the first electrospinning nozzle and the first friction disc is 7cm, and the distance between the second electrospinning nozzle and the second friction disc is 7cm.

[0084] The viscosity of the obtained modified polyvinyl alcohol fiber is 40.5 Pa·s.

[0085] The triboelectric properties of the multi-electrode triboelectric fiber prepared in this embodiment were tested using the same method as in Example 1, and the test results are shown in Table 3.

[0086]

[0087] Example 4:

[0088] This example provides a method for preparing multi-electrode triboelectric fibers and the resulting multi-electrode triboelectric fibers, which are basically the same as in Example 1, except that:

[0089] Heat and stir in a water bath for 75 minutes to prepare a 20% PVA solution. Then add an appropriate amount of high-purity silver powder to the PVA solution to make the concentration of silver powder in the PVA solution 0.12 g / mL.

[0090] The number of copper wires is 8, and the diameter of the copper wires is 0.3mm. During the false twisting process, the process parameters are as follows: the speed at which the wire leaves the friction disc false twister is 650m / h, the rotation speed of the friction disc is 150r / min, the stretch ratio is 1.115, the ratio of the surface speed of the friction disc to the speed at which the wire leaves the false twister is 1.8, the ratio of the twisting tension T1 to the untwisting tension T2 is 0.85, and the temperature of the hot box is 245℃.

[0091] The distance between the first electrospinning nozzle and the first friction disc is 10cm, and the distance between the second electrospinning nozzle and the second friction disc is 10cm.

[0092] The viscosity of the obtained modified polyvinyl alcohol fiber is 72.57 Pa·s.

[0093] The triboelectric properties of the multi-electrode triboelectric fiber prepared in this embodiment were tested using the same method as in Example 1, and the test results are shown in Table 4.

[0094]

[0095] Example 5:

[0096] This example provides a method for preparing multi-electrode triboelectric fibers and the resulting multi-electrode triboelectric fibers, which are basically the same as in Example 1, except that:

[0097] Heat and stir in a water bath for 75 minutes to prepare a 20% PVA solution. Then add an appropriate amount of high-purity silver powder to the PVA solution to make the concentration of silver powder in the PVA solution 0.12 g / mL.

[0098] The number of copper wires is 8, and the diameter of the copper wires is 0.3mm. During the false twisting process, the process parameters are as follows: the speed at which the wire leaves the friction disc false twister is 650m / h, the rotation speed of the friction disc is 175r / min, the stretch ratio is 1.115, the ratio of the surface speed of the friction disc to the speed at which the wire leaves the false twister is 1.8, the ratio of the twisting tension T1 to the untwisting tension T2 is 0.85, and the temperature of the hot box is 285℃.

[0099] The distance between the first electrospinning nozzle and the first friction disc is 10cm, and the distance between the second electrospinning nozzle and the second friction disc is 10cm.

[0100] The viscosity of the obtained modified polyvinyl alcohol fiber is 72.57 Pa·s.

[0101] The triboelectric properties of the multi-electrode triboelectric fiber prepared in this embodiment were tested using the same method as in Example 1, and the test results are shown in Table 5.

[0102]

[0103] According to GB / T 14344-2008 "Test Method for Tensile Properties of Chemical Fiber Filaments", the tensile properties of the examples were tested using a constant rate of elongation tester. 60cm specimens were prepared according to GB / T 6502, and the tensile rate was 50mm / min. The results showed that the elongation rate could reach more than 55%.

[0104] Comparative Example 1:

[0105] It is basically the same as Example 1, except that the number of copper wires is 1.

[0106] The triboelectric properties of the triboelectric fiber prepared in this embodiment were tested using the same method as in Example 1, and the test results are shown in Table 6.

[0107]

[0108] Comparative Example 2:

[0109] The results are essentially the same as in Example 1, except that the concentration of the PVA solution is 8%, and the viscosity of the resulting modified polyvinyl alcohol fiber is 2.08 Pa·s. Practice has shown that it cannot act as a binder and therefore cannot be used to prepare triboelectric fibers.

[0110] Comparative Example 3:

[0111] The process is basically the same as in Example 1, except that: the four copper wires are not processed by the friction disc false twister, and the spun modified polyvinyl alcohol fiber is directly wrapped on the copper wire, and then the spun SEBS fiber is wrapped on the outermost layer to make a multi-electrode triboelectric fiber.

[0112] According to GB / T 14344-2008 "Test Method for Tensile Properties of Chemical Fiber Filaments", the tensile properties of the examples were tested using a constant rate of elongation tester. A 60cm specimen was prepared according to GB / T 6502, and the tensile rate was 50mm / min. The results showed that the fiber broke when the elongation was 40%.

[0113] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

[0114] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

Claims

1. A method for preparing a multi-electrode triboelectric fiber, characterized in that, The preparation method includes: Multiple copper wires are false-twisted using a friction disc false twister. The friction disc false twister includes a friction disc shaft made of insulating material and a first friction disc and a second friction disc respectively arranged on the friction disc shaft from top to bottom. The first friction disc and the second friction disc are both made of carbon fiber. Modified polyvinyl alcohol fibers are spun out by the first electrospinning mechanism and attached to the first friction disc, and SEBS fibers are spun out by the second electrospinning mechanism and attached to the second friction disc. During the false twisting process, the multiple copper wires first rub against the first friction disc, and then rub against the second friction disc. A double-layer coating structure with an inner layer and an outer layer is formed sequentially on the surface of the multiple copper wires. The inner layer is formed by coating with modified polyvinyl alcohol fiber, and the outer layer is formed by coating with SEBS fiber. The modified polyvinyl alcohol fiber is produced by spinning a polyvinyl alcohol spinning solution containing silver powder. The polyvinyl alcohol spinning solution containing silver powder has a silver powder content of 0.04-0.12 g / mL, a polyvinyl alcohol concentration of 14%-20%, and a molecular weight of 50,000-180,000.

2. The method for preparing multi-electrode triboelectric fibers according to claim 1, characterized in that, The diameter of a single copper wire is controlled to be less than 0.5 mm, the number of copper wires is 2-8, and the total diameter of the multiple copper wires is less than 3 mm.

3. The method for preparing multi-electrode triboelectric fibers according to claim 1, characterized in that, During the preparation process, the resulting multi-electrode triboelectric fiber is grounded.

4. The method for preparing multi-electrode triboelectric fibers according to claim 1, characterized in that, During the false twisting process, the stretch ratio is 1.110-1.115, the ratio of the surface velocity of each friction disc to the velocity of the filament leaving the friction disc false twister is 1.65-1.80, the velocity of the filament leaving the friction disc false twister is 450-650 m / h, the ratio of twisting tension T1 to untwisting tension T2 is 0.75-0.85, and the rotational speed of each friction disc is independently 150-200 r / min.

5. The method for preparing multi-electrode triboelectric fibers according to claim 1, characterized in that, The molecular weight of the polyvinyl alcohol is 80,000-140,000.

6. The method for preparing multi-electrode triboelectric fibers according to claim 1, characterized in that, The SEBS fiber is produced by spinning a SEBS spinning solution, which is obtained by dispersing SEBS in cyclohexane, and the mass concentration of SEBS in the SEBS spinning solution is 10%-20%.

7. The method for preparing multi-electrode triboelectric fibers according to claim 1, characterized in that, The distance between the spinning nozzle of the first electrospinning mechanism and the first friction disc, and the distance between the spinning nozzle of the second electrospinning mechanism and the second friction disc are both 5-10cm.

8. The method for preparing multi-electrode triboelectric fibers according to claim 1, characterized in that, During the spinning of the modified polyvinyl alcohol fiber, the flow rate of the polyvinyl alcohol spinning solution containing silver powder is 0.1-0.3 mL / h; In the process of spinning the SEBS fibers, they are produced by spinning a SEBS spinning solution at a flow rate of 0.6-0.8 mL / h.

9. A multi-electrode triboelectric fiber prepared by the preparation method of any one of claims 1-8.

10. The application of the multi-electrode triboelectric fiber of claim 9 in the fabrication of a deformation sensor.

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