CN114923604A - Metal core piezoelectric piezoresistive composite fiber and preparation method thereof - Google Patents
Metal core piezoelectric piezoresistive composite fiber and preparation method thereof Download PDFInfo
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- G01L1/00—Measuring force or stress, in general
- G01L1/18—Measuring force or stress, in general using properties of piezo-resistive materials, i.e. materials of which the ohmic resistance varies according to changes in magnitude or direction of force applied to the material
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- G01L9/02—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means by making use of variations in ohmic resistance, e.g. of potentiometers, electric circuits therefor, e.g. bridges, amplifiers or signal conditioning
- G01L9/06—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means by making use of variations in ohmic resistance, e.g. of potentiometers, electric circuits therefor, e.g. bridges, amplifiers or signal conditioning of piezo-resistive devices
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Abstract
The invention discloses a piezoelectric piezoresistive composite fiber and a preparation method thereof, wherein the composite fiber sequentially comprises a metal core electrode, a piezoelectric layer, a middle electrode, a piezoresistive layer and an external electrode from inside to outside; wherein the metal core electrode is a copper polyimide enameled wire; the piezoelectric layer comprises a PVDF film pressure-sensitive layer and an insulating protective layer; the metal core electrode and the intermediate electrode serve as two electrodes; the piezoresistive layer is a PU-MWCNT (polyurethane-multi-walled carbon nanotube) composite pressure-sensitive material; the middle electrode and the outer electrode serve as two electrodes. The piezoelectric piezoresistive composite fiber is prepared by an electrowetting method in an auxiliary manner, the piezoelectric layer and the piezoresistive layer are attached to the metal core electrode in a coaxial manner by the electrowetting auxiliary method in sequence, and polyimide on the surface of the metal core is used as an electrowetting dielectric layer. The piezoelectric layer and the piezoresistive layer of the invention respectively bear the detection functions of dynamic force and static force. The invention has the advantages of small size, easy array, flexibility, suitability for loading small-size complex curved surfaces and dynamic/static force sensitivity.
Description
Technical Field
The invention relates to a metal core composite fiber with a core-shell structure, in particular to a metal core piezoelectric piezoresistive composite fiber and a preparation method thereof.
Background
The metal core piezoelectric fiber is a sensing unit which can be used in the fields of bionic airflow sensors, wearable intelligent fabrics, engineering structure health monitoring and the like. Metal-core piezoelectric fibers have many advantages over typical piezoelectric fibers without a metal core, such as being integrated on more complex surfaces; for example, each fiber works independently to improve the robustness of the system; such as not distributing the dielectric properties of the substrate; such as the advantages of fast adaptation and dynamic response.
Although the metal core piezoelectric fiber has good application prospect, the preparation method, the dynamic/static force sensitivity and the tensile strength limit the wide application of the metal core piezoelectric fiber. For a melting die wire pressing method commonly adopted for preparing the metal core piezoelectric fiber, the electro-infiltration auxiliary wire drawing method has the advantages of simple equipment, self polarization, high core-shell combination degree and long-size wire drawing, and accelerates the industrialization progress of the metal core piezoelectric fiber; the piezoelectric material of the metal core piezoelectric fiber can only detect dynamic force, so the application of the metal core piezoelectric fiber in the occasions (such as posture and strain damage) needing to detect static force in soft robots and structural health detection is limited. The composite piezoresistive layer can simultaneously detect dynamic and static forces, and makes up for the defect of static force detection; the metal core piezoelectric fiber does not have strong tensile property due to the material property of the metal core piezoelectric fiber, so that the use of the metal core piezoelectric fiber in practical application occasions is influenced. Therefore, a metal core piezoelectric piezoresistive composite fiber sensor is developed on the basis of the metal core piezoelectric fiber sensor.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a metal core piezoelectric piezoresistive composite fiber and a preparation method thereof.
A metal core piezoelectric piezoresistive composite fiber is characterized in that:
the composite fiber has a core-shell structure and sequentially comprises a metal core electrode, a piezoelectric layer, a middle electrode, a piezoresistive layer and an external electrode from inside to outside; the outer layer of the metal core electrode is coated with a layer of polyimide paint; the piezoelectric layer comprises a PVDF (polyvinylidene fluoride) film pressure-sensitive layer and an insulating protective layer which is arranged outside the PVDF (polyvinylidene fluoride) film pressure-sensitive layer and is composed of a parylene film; the polyimide dielectric film serves as an essential part of the electrowetting process on the one hand, and also increases the affinity of the metal core for the PVDF polymer solution to some extent on the other hand.
Preferably, the intermediate electrode is formed of a magnetron sputtered copper film.
Preferably, the piezoresistive layer is made of polyurethane elastomer with multi-wall carbon nano tubes uniformly dispersed.
Preferably, the external electrode is formed of a magnetron sputtered copper film.
Preferably, the insulating protective layer is formed of a chemical vapor deposited parylene film.
Preferably, the metal core electrode is a copper wire coated with a layer of polyimide varnish.
A preparation method of a metal core piezoelectric piezoresistive composite fiber is characterized in that a preparation device is an electrowetting device, and the electrowetting device comprises: the device comprises an electro-infiltration auxiliary device, a copper needle head, a metal tube electrode, a bearing wheel, a wire through hole, a collecting device and a wire winding wheel;
the preparation process of the metal core piezoelectric piezoresistive composite fiber comprises the following steps:
step one, mounting a metal core coated with a layer of polyimide paint on a winding wheel, bypassing a bearing wheel in an electrowetting auxiliary device, passing through a copper needle head, a metal tube and a metal tube electrode, passing through a wire through hole, scraping a part of paint on the metal core by using a blade, exposing a part of the metal core, connecting the exposed part of the metal core with a conductor of a collecting device to be grounded, straightening the metal core by using a pretightening force adjusting device, and centering by manual adjustment;
step two, adding PVDF (polyvinylidene fluoride) powder into a mixed solution of acetone and DMF (dimethylformamide), wherein the mass ratio of acetone to DMF (dimethylformamide) is 4: 6, after sealing is well done, magnetic stirring is carried out under the heating condition until PVDF (polyvinylidene fluoride) powder is completely dissolved, a PVDF (polyvinylidene fluoride) solution with the mass concentration of 20% is prepared, the cooled PVDF (polyvinylidene fluoride) solution is transferred into a copper needle, the voltage of the copper needle is set to be 3kV, the voltage of a metal pipe is set to be 2kV, and the wire drawing process is carried out under the room temperature condition;
after the drawing is finished, cutting the piezoelectric fiber obtained by drawing into required length, cleaning and drying by using deionized water, coating a coupling agent on the surface of the piezoelectric fiber after drying, putting the piezoelectric fiber into a coating chamber, and performing chemical vapor deposition parylene coating under the condition of vacuum degree of 2 x 10-2 Torr;
step four, cleaning the sample prepared in the step three, drying the sample, and plating a layer of copper film on the surface of the sample by a magnetron sputtering method;
step five, weighing a certain amount of MWCNT (multi-walled carbon nanotube) and dispersing the MWCNT (multi-walled carbon nanotube) in NMP (methyl pyrrolidone) by taking PVP (polyvinylpyrrolidone) as a dispersing agent, and performing ultrasonic dispersion after magnetic stirring to obtain MWCNT (multi-walled carbon nanotube) solution; weighing a certain amount of PU (polyurethane) particles, putting the PU (polyurethane) particles into DMF (dimethyl formamide), and magnetically stirring until PU (polyurethane) is completely dissolved to obtain a PU (polyurethane) solution; mixing and stirring MWCNT (multi-walled carbon nanotube) solution and PU (polyurethane) solution to obtain PU-MWCNT (polyurethane-multi-walled carbon nanotube) mixed solution;
and step six, transferring the solution obtained in the previous step into a copper needle by using a needle tube, controlling the voltage of the copper needle to be 3KV, and performing parameter wire drawing to obtain the piezoresistive layer. The principle of the electro-infiltration auxiliary wire drawing is that on the premise of electrifying the solution, the copper core of the metal core electrode is grounded, and the solution can increase the affinity degree with the metal core electrode under the action of electrostatic force and can make the surface appearance smoother and more stable;
and seventhly, cleaning and drying the sample again on the basis of the previous step, and plating a layer of copper film with the thickness of 1 mu m on the whole section of the sample by using a magnetron sputtering method to be used as an external electrode. And obtaining the metal core piezoelectric piezoresistive composite fiber after the completion.
The invention has the following beneficial effects:
1. in the preparation process, the electro-wetting auxiliary filamentation is used, the high-temperature condition of the traditional molten high polymer wiredrawing is improved, the PVDF (polyvinylidene fluoride) can be stretched and polarized, the problem of low affinity between the traditional polymer and a metal core is solved, and the wiredrawing process is simplified to a great extent;
2. compared with pure PVDF material fiber, the metal core fiber has great advantages: the dielectric properties of the array substrate are not required; can be integrated on more complex surfaces; each composite fiber can work independently, and the whole system has stronger robustness;
3. the parylene film is applied to the preparation of the metal core piezoelectric fiber for the first time, the parylene coating has the advantages of complete shape, uniform thickness, chemical corrosion resistance and excellent electrical property, and the problems of insufficient tensile strength and abrasion resistance of the metal core piezoelectric fiber are solved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is within the scope of the present invention for those skilled in the art to obtain other drawings based on the drawings without inventive exercise.
FIG. 1 is a schematic view of the structure of a metal core piezoelectric piezoresistive composite fiber according to the present invention;
FIG. 2 is an enlarged view of a portion of the metal core electrode of the present invention;
FIG. 3 is an axial view of the metal core piezoelectric piezoresistive composite fiber of the present invention;
FIG. 4 is an enlarged view of a portion of the electrowetting assistance device of the present invention;
FIG. 5 is a three-dimensional view of the copper needle of the present invention;
FIG. 6 is an exploded view of the copper needle of the present invention;
FIG. 7 is an enlarged top view of a single metal tube electrode of the present invention;
FIG. 8 is a three-dimensional view of a drawing bench of the present invention;
FIG. 9 is a front view of the drawing station of the present invention;
FIG. 10 is a schematic drawing trace of the present invention;
in the figure: 1. a metal core electrode; 2. a piezoelectric layer; 3. an intermediate electrode; 4. a piezoresistive layer; 5. an external electrode; 6. polyimide paint; 7. a copper wire; 8. a PVDF film pressure-sensitive layer; 9. an insulating protective layer; 10. an electrowetting assistance device; 11. a copper needle head; 11a, the upper part of the copper needle head; 11b, the lower part of the copper needle head; 12. a metal tube electrode; 13. A bearing wheel; 14. a nut; 15. a fixing plate; 16. compressing the spring; 17. a conductive metal block; 18. a metal tube; 19. a support frame; 20. a threading hole; 21. a collection device; 22. a high voltage power supply; 23. a wire wheel base; 24. a wire winding wheel.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings.
The terms of direction and position of the present invention, such as "up", "down", "front", "back", "left", "right", "inside", "outside", "top", "bottom", "side", etc., refer to the direction and position of the attached drawings. Accordingly, the terms of orientation and position are used for the purposes of illustration and understanding, and are not intended to limit the scope of the invention.
A metal core piezoelectric piezoresistive composite fiber is characterized in that:
the composite fiber has a core-shell structure and sequentially comprises a metal core electrode 1, a piezoelectric layer 2, a middle electrode 3, a piezoresistive layer 4 and an external electrode 5 from inside to outside; the outer layer of the metal core electrode 1 is coated with a layer of polyimide paint 6; the piezoelectric layer 2 comprises a PVDF (polyvinylidene fluoride) film pressure-sensitive layer 8 and an insulating protective layer 9 which is arranged outside the PVDF (polyvinylidene fluoride) film pressure-sensitive layer 8 and is composed of a parylene film.
The middle electrode 3 is composed of a copper film formed by magnetron sputtering.
The piezoresistive layer 4 is made of polyurethane elastomer with multi-wall carbon nano tubes uniformly dispersed.
The external electrode is composed of a magnetron sputtered copper film.
The insulating protective layer 9 is formed by a chemical vapor deposition parylene film.
The metal core electrode 1 is a copper wire coated with a layer of polyimide paint.
A preparation method of a metal core piezoelectric piezoresistive composite fiber is characterized in that a preparation device is an electrowetting device, and the electrowetting device comprises: the device comprises an electro-wetting auxiliary device 10, a copper needle 11, a metal tube electrode 12, a bearing wheel 13, a harness cord hole 20, a collecting device 21 and a winding wheel 24.
The preparation process of the metal core piezoelectric piezoresistive composite fiber comprises the following steps:
step one, mounting a metal core coated with a layer of polyimide paint on a winding wheel 24, bypassing a bearing wheel 13 in an electrowetting auxiliary device 10, passing through a copper needle 11 and a metal tube electrode 12, passing through a through wire hole 20, scraping a part of the paint on the metal core by a blade, exposing a part of the metal core, connecting the part of the metal core with a conductor of a collecting device 21 for grounding, straightening the metal core by a pretightening force adjusting device, and centering by manual adjustment;
step two, adding PVDF (polyvinylidene fluoride) powder into a mixed solution of acetone and DMF (dimethylformamide), wherein the mass ratio of acetone to DMF (dimethylformamide) is 4: and 6, after sealing is well done, magnetic stirring is carried out under the heating condition until PVDF (polyvinylidene fluoride) powder is completely dissolved to prepare a PVDF (polyvinylidene fluoride) solution with the mass concentration of 20%, the cooled PVDF (polyvinylidene fluoride) solution is transferred to a copper needle, the voltage of the copper needle 11 is set to be 3kV, and the voltage of the metal tube electrode 12 is set to be 2 kV. The wire drawing process is carried out at room temperature;
after the wire drawing is finished, cutting the piezoelectric fiber obtained by wire drawing into required length, cleaning and drying the piezoelectric fiber by using deionized water, coating a coupling agent on the surface of the piezoelectric fiber after drying, putting the piezoelectric fiber into a film coating chamber, and performing chemical vapor deposition parylene coating under the condition of vacuum degree of 2 x 10-2 Torr;
step four, cleaning and drying the sample prepared in the step three, and plating a layer of copper film on the surface of the sample by a magnetron sputtering method;
step five, weighing a certain amount of MWCNT (multi-walled carbon nanotube) and dispersing the MWCNT (multi-walled carbon nanotube) in NMP (methyl pyrrolidone) by taking PVP (polyvinylpyrrolidone) as a dispersing agent, and performing ultrasonic dispersion after magnetic stirring to obtain MWCNT (multi-walled carbon nanotube) solution; weighing a certain amount of PU (polyurethane) particles, putting the PU (polyurethane) particles into DMF (dimethyl formamide), and magnetically stirring until PU (polyurethane) is completely dissolved to obtain a PU (polyurethane) solution; mixing and stirring an MWCNT (multi-walled carbon nanotube) solution and a PU (polyurethane) solution to obtain a PU-MWCNT (polyurethane-multi-walled carbon nanotube) mixed solution;
and step six, transferring the solution in the previous step into a copper needle 11 by using a needle tube, controlling the voltage of the copper needle 11 to be 3KV, and controlling parameter wire drawing to obtain the piezoresistive layer 4. The principle of the electro-infiltration auxiliary wire drawing is that on the premise of electrifying the solution, the copper core of the metal core electrode 1 is grounded, and the solution can increase the affinity degree with the metal core electrode 1 under the action of electrostatic force and can make the surface appearance smoother and more stable;
and seventhly, cleaning and drying the sample again on the basis of the previous step, and plating a layer of copper film with the thickness of 1 mu m on the whole section of the sample by using a magnetron sputtering method to be used as an external electrode. And obtaining the metal core piezoelectric piezoresistive composite fiber after the completion.
As shown in fig. 1, which is a schematic structural diagram of an embodiment of the present invention, a metal core piezoelectric piezoresistive composite fiber has a core-shell structure, and the metal core piezoelectric piezoresistive composite fiber with the core-shell structure is composed of, from inside to outside, a metal core electrode 1, a piezoelectric layer 2, a middle electrode 3, a piezoresistive layer 4, and an external electrode 5 in sequence; the partial enlarged structure of the metal core electrode 1 is shown in figure 2, a layer of polyimide varnish 6 is coated on a copper wire 7, the thickness of the polyimide varnish is 15 microns, the diameter of the copper wire is 0.14mm, and the model is QYN-2B/240.
The piezoelectric layer 2 consists of a PVDF film pressure-sensitive layer 8 and an insulating protective layer 9, the piezoelectric layer 2 is a PVDF film with the thickness of 30 microns, which is manufactured by a solution method, and the insulating protective layer 9 is a parylene film with the thickness of 15 microns, which is deposited by chemical vapor deposition; the middle electrode 3 is a 200nm copper film plated outside the insulating protective layer 9 through magnetron sputtering; the piezoresistive layer 4 is made of multi-walled carbon nanotubes as conductive filler filled in polyurethane as an elastomer, and has a thickness of 30 μm.
As shown in fig. 4, the main body structure 10 of the electrowetting auxiliary device is composed of a copper needle 11, a bearing wheel 13, and a metal tube electrode 12, wherein the upper portion 11a of the copper needle and the metal tube electrode 12 are both formed by metal cutting, and the others are all made of PP (polypropylene).
As shown in fig. 5 and 6, the copper needle 11 is composed of a copper needle upper part 11a and a copper needle lower part 11b, the copper needle lower part 11b is made of a non-metal resin material through 3D printing, the diameter of a lower through hole is 1mm, and the thickness of the metal core piezoelectric fiber can be adjusted by replacing the copper needle lower part 11 b.
As shown in fig. 7, the metal tube electrode 12 is composed of a nut 14, a fixing plate 15, a pressure spring 16, a conductive metal block 17, and a metal tube 18, and is a device for applying an external electric field to the wire. The part is formed by seven metal tube electrodes 12 with reduced inner diameters, wherein the middle metal tube 18 is clamped by the elasticity generated by a pressure spring 16.
As shown in fig. 8 and 9, the wire drawing table is composed of an electro-wetting auxiliary device 10, a support frame 19, a collecting device 21, a high-voltage power supply 21 and a wire wheel base 23. A through-hole 20 is provided between the electrowetting assistance device 10 and the support frame 19. The wire drawing table is integrally made into a vertical type so as to adjust the shortest length of a single wire drawing, a longer length is needed for improving efficiency when manufacturing a piezoelectric wire, and the length of the single wire drawing is needed to be shortened as much as possible for conveniently plating the intermediate electrode 3 and secondary wire drawing when attaching the piezoresistive layer 4.
As shown in fig. 10, the motion trajectory of the metal core electrode 1 is: the winding wheel 24 → the electro-infiltration assisting device 10 → the through hole 20 → the collecting device 21;
the working principle of the metal core piezoelectric piezoresistive composite fiber sensor is as follows: when the surface of the fiber body is pressed by external force, the piezoresistive layer 4 is firstly pressed, the insulating protective layer 9 serves as a pressure conduction medium, when the piezoelectric layer 2 is pressed by the external force, the upper surface and the lower surface of the PVDF film pressure-sensitive layer 8 generate electric charges, the insulating protective layer 9 serves as a dielectric medium, the middle electrode 3 and the metal core on the surface of the insulating protective layer 8 are respectively connected with the external electrode 5 through leads, and the dynamic force on the surface of the composite fiber is reversely released by detecting the electric charges. When the fiber is bent and deformed or directly stressed, the internal resistivity of the piezoresistive layer 4 changes, the middle electrode 3 and the external electrode 5 are respectively connected with the lead wires, and the static force applied to the surface is detected by detecting the change of the resistivity, so that the function of composite measurement of the dynamic force and the static force is realized.
The embodiment also discloses a preparation method of the metal core piezoelectric piezoresistive composite fiber, which comprises the following steps:
step S1, mounting the metal core coated with a layer of polyimide paint on a winding wheel 24, bypassing a bearing wheel 13 in an electrowetting auxiliary device 10, passing through a copper needle 11, a metal tube 18 and a metal tube electrode 12, passing through a through hole 20, scraping a part of the paint on the metal core by using a blade, exposing a part of the metal core, connecting the part of the metal core with a conductor of a collecting device 21 for grounding, straightening the metal core by using a pre-tightening force adjusting device, and centering by manual adjustment;
step S2, weighing a certain amount of PVDF powder, adding the PVDF powder into a mixed solution of acetone and DMF (dimethyl formamide), wherein the mass ratio of the acetone to the DMF is 4: 6, after sealing is done, magnetically stirring for 2 hours at the heating condition of 40 ℃ until the PVDF powder is completely dissolved to prepare a PVDF solution with the mass concentration of 20%. The cooled PVDF solution was drawn out by a syringe and transferred to a copper needle 11, the voltage of the copper needle 11 was set to 3kV, and the voltage of the metal tube 11 was set to 2 kV. The drawing process is carried out at room temperature.
And step S3, after wire drawing is finished, cutting the metal core piezoelectric fibers into a length of 1m, washing the metal core piezoelectric fibers for 10min by using deionized water, drying the metal core piezoelectric fibers for half an hour at the temperature of 60 ℃, coating a coupling agent on the surfaces of the metal core piezoelectric fibers, putting the metal core piezoelectric fibers into a coating chamber, performing chemical vapor deposition of a parylene film at room temperature for 10h under the condition that the vacuum degree is 2 x 10-2Torr, and obtaining the film with the thickness of 20 mu m after the completion.
And step S4, on the basis of the previous step, cleaning and drying the sample again, and plating a layer of 1-micron copper film on the whole section of the sample by using a magnetron sputtering method.
Step S5, weighing a certain amount of MCWNT (multi-walled carbon nanotube) and dispersing in NMP (methyl pyrrolidone) by taking PVP (polyvinylpyrrolidone) as a dispersing agent, firstly magnetically stirring for 1h, and then ultrasonically dispersing for 1 h. Weighing a certain amount of PU (polyurethane) particles into DMF, and magnetically stirring at 40 ℃ until PU is completely dissolved. Mixing and stirring the two solutions for 1h to obtain a PU-MWCNT mixed solution.
And step S6, transferring the solution obtained in the previous step into a copper needle 11 by using a needle tube, controlling the voltage of the copper needle 11 to be 3KV, and performing parameter wire drawing to obtain the piezoresistive layer 4. The principle of the electro-infiltration auxiliary wire drawing is that under the premise of electrifying the solution, the copper core of the metal core electrode 1 is grounded, and the solution can increase the affinity degree with the metal core electrode under the action of electrostatic force and can make the surface appearance smoother and more stable.
And step S7, on the basis of the previous step, cleaning and drying the sample again, and plating a layer of 1 micron copper film on the whole section of the sample by a magnetron sputtering method to be used as an external electrode 5. And obtaining the metal core piezoelectric piezoresistive composite fiber after the completion.
According to the steps, the manufactured metal core piezoelectric piezoresistive composite fiber has excellent dynamic and static force simultaneous detection performance, is beneficial to being attached to a complex curved surface, can deform randomly and can feed back the curvature and vibration information of a physical structure.
It will be understood by those skilled in the art that all or part of the steps in the method for implementing the above embodiments may be implemented by relevant hardware instructed by a program, and the program may be stored in a computer-readable storage medium, such as ROM/RAM, magnetic disk, optical disk, etc.
The above disclosure is only for the purpose of illustrating the preferred embodiments of the present invention, and it is therefore to be understood that the invention is not limited by the scope of the appended claims.
Claims (9)
1. A metal core piezoelectric piezoresistive composite fiber is characterized in that:
the composite fiber has a core-shell structure and sequentially comprises a metal core electrode (1), a piezoelectric layer (2), a middle electrode (3), a piezoresistive layer (4) and an external electrode (5) from inside to outside;
the outer layer of the metal core electrode (1) is coated with a layer of polyimide paint (6); the piezoelectric layer (2) comprises a PVDF film pressure-sensitive layer (8) and an insulating protective layer (9) which is arranged outside the PVDF film pressure-sensitive layer (8) and is composed of a parylene film.
2. The metal core piezoelectric piezoresistive composite fiber according to claim 1, wherein: the intermediate electrode (3) is formed by a copper film formed by magnetron sputtering.
3. The metal core piezoelectric piezoresistive composite fiber according to claim 1, wherein: the piezoresistive layer (4) is composed of polyurethane elastomer with multi-wall carbon nano tubes uniformly dispersed.
4. The metal core piezoelectric piezoresistive composite fiber according to claim 1, wherein: the external electrode is composed of a magnetron sputtered copper film.
5. The metal core piezoelectric piezoresistive composite fiber according to claim 1, wherein: the insulating protective layer (9) is formed by a chemical vapor deposition parylene film.
6. The metal core piezoelectric piezoresistive composite fiber according to claim 1, wherein: the metal core electrode (1) is a copper wire coated with a layer of polyimide paint.
7. The method for preparing the metal core piezoelectric piezoresistive composite fiber according to any one of claims 1 to 6, wherein the preparation device is an electrowetting device, and the electrowetting device comprises: the device comprises an electro-wetting auxiliary device (10), a copper needle head (11), a metal tube electrode (12), a bearing wheel (13), a harness cord hole (20), a collecting device (21) and a winding wheel (24);
the preparation process of the metal core piezoelectric piezoresistive composite fiber comprises the following steps:
step one, mounting a metal core coated with a layer of polyimide paint on a winding wheel (24), winding a bearing wheel (13) in an electrowetting auxiliary device (10), penetrating a copper needle (11) and a metal tube electrode (12), penetrating a through hole (20), scraping a part of the paint on the metal core by using a blade, exposing a part of the metal core, connecting the part of the paint with a conductor of a collecting device (21) to be grounded, straightening the metal core by using a pretightening force adjusting device, and centering by manual adjustment;
step two, adding PVDF powder into a mixed solution of acetone and DMF, wherein the mass ratio of acetone to DMF is 4: stirring until the PVDF powder is completely dissolved to prepare a PVDF solution, transferring the cooled PVDF solution into a copper needle, setting the voltage of the copper needle to be 3kV, setting the voltage of a metal tube electrode to be 2kV, and carrying out the wire drawing process at room temperature;
step three, after wire drawing is finished, cleaning and drying the piezoelectric fiber obtained by wire drawing by using deionized water, coating a coupling agent on the surface of the piezoelectric fiber after drying, putting the piezoelectric fiber into a film coating chamber, and performing chemical vapor deposition parylene coating under the condition of vacuum degree of 2 x 10-2 Torr;
step four, cleaning and drying the sample prepared in the step three, and plating a layer of copper film on the surface of the sample as an intermediate electrode by a magnetron sputtering method;
step five, weighing a certain amount of MWCNT, dispersing the MWCNT in NMP by taking PVP as a dispersing agent, magnetically stirring, and then performing ultrasonic dispersion to obtain an MWCNT solution; weighing a certain amount of PU particles, putting the PU particles into DMF, and magnetically stirring until PU is completely dissolved to obtain a PU solution; mixing and stirring the MWCNT solution and the PU solution to obtain a PU-MWCNT mixed solution;
sixthly, transferring the PU-MWCNT mixed solution obtained in the fifth step into a copper needle, controlling the parameters to perform wire drawing to obtain a piezoresistive layer, wherein the voltage of the copper needle is 3KV, and the voltage of a metal tube electrode is 2 KV;
and step seven, cleaning and drying the sample obtained in the step six, and plating a layer of copper film on the whole section of the sample by a magnetron sputtering method to be used as an external electrode to obtain the metal core piezoelectric piezoresistive composite fiber.
8. The metal-core piezoelectric piezoresistive composite fiber is characterized by being prepared by the preparation method of the metal-core piezoelectric piezoresistive composite fiber according to claim 7.
9. A sensor comprising a metal core piezoelectric piezoresistive composite fibre according to any of claims 1 to 6 or 8.
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Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09505899A (en) * | 1995-02-07 | 1997-06-10 | インターナシヨナル・ビジネス・マシーンズ・コーポレーシヨン | Cantilever shake sensor and method of using the same |
| JP2005257326A (en) * | 2004-03-09 | 2005-09-22 | Nippon Telegr & Teleph Corp <Ntt> | Semiconductor detecting element and detection method |
| CN101776495A (en) * | 2010-03-12 | 2010-07-14 | 浙江大学 | Micro/nano fiber structure-based touch sensor and preparation method thereof |
| KR20150046631A (en) * | 2013-10-22 | 2015-04-30 | 삼성전기주식회사 | Piezoresistance Sensor module and MEMS Sensor having the same |
| CA2848430A1 (en) * | 2014-04-03 | 2015-10-03 | Peyman Servati | Coreshell nanofiber textiles for strain sensing, and methods of their manufacture |
| CN109307565A (en) * | 2018-08-21 | 2019-02-05 | 厦门大学 | It is a kind of can induction pressure flexible electronic skin and preparation method thereof |
| CN111270414A (en) * | 2020-03-23 | 2020-06-12 | 清华大学深圳国际研究生院 | Flexible piezoelectric fiber membrane and preparation method and application thereof |
| CN112025750A (en) * | 2020-09-02 | 2020-12-04 | 温州大学 | Piezoelectric piezoresistive composite humanoid tactile finger and preparation method thereof |
| CN112284577A (en) * | 2020-09-27 | 2021-01-29 | 西安交通大学 | Piezoelectric piezoresistive combined type touch sensor and preparation method thereof |
| CN113235310A (en) * | 2021-05-07 | 2021-08-10 | 北京航空航天大学 | Preparation method and application of piezoresistive sensing fabric |
| US20210384493A1 (en) * | 2020-06-08 | 2021-12-09 | Vanderbilt University | Composite fiber electrodes and applications of same |
-
2022
- 2022-04-09 CN CN202210370362.4A patent/CN114923604B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09505899A (en) * | 1995-02-07 | 1997-06-10 | インターナシヨナル・ビジネス・マシーンズ・コーポレーシヨン | Cantilever shake sensor and method of using the same |
| JP2005257326A (en) * | 2004-03-09 | 2005-09-22 | Nippon Telegr & Teleph Corp <Ntt> | Semiconductor detecting element and detection method |
| CN101776495A (en) * | 2010-03-12 | 2010-07-14 | 浙江大学 | Micro/nano fiber structure-based touch sensor and preparation method thereof |
| KR20150046631A (en) * | 2013-10-22 | 2015-04-30 | 삼성전기주식회사 | Piezoresistance Sensor module and MEMS Sensor having the same |
| CA2848430A1 (en) * | 2014-04-03 | 2015-10-03 | Peyman Servati | Coreshell nanofiber textiles for strain sensing, and methods of their manufacture |
| CN109307565A (en) * | 2018-08-21 | 2019-02-05 | 厦门大学 | It is a kind of can induction pressure flexible electronic skin and preparation method thereof |
| CN111270414A (en) * | 2020-03-23 | 2020-06-12 | 清华大学深圳国际研究生院 | Flexible piezoelectric fiber membrane and preparation method and application thereof |
| US20210384493A1 (en) * | 2020-06-08 | 2021-12-09 | Vanderbilt University | Composite fiber electrodes and applications of same |
| CN112025750A (en) * | 2020-09-02 | 2020-12-04 | 温州大学 | Piezoelectric piezoresistive composite humanoid tactile finger and preparation method thereof |
| CN112284577A (en) * | 2020-09-27 | 2021-01-29 | 西安交通大学 | Piezoelectric piezoresistive combined type touch sensor and preparation method thereof |
| CN113235310A (en) * | 2021-05-07 | 2021-08-10 | 北京航空航天大学 | Preparation method and application of piezoresistive sensing fabric |
Non-Patent Citations (4)
| Title |
|---|
| P. DARIO 等: "An integrated miniature fingertip sensor", 《MHS\'96 PROCEEDINGS OF THE SEVENTH INTERNATIONAL SYMPOSIUM ON MICRO MACHINE AND HUMAN SCIENCE》 * |
| 夏咸龙;周桂祥;边义祥;王昌龙;: "表面部分电极含金属芯压电纤维气流传感特性研究", 传感技术学报 * |
| 边义祥 等: "一种仿生感觉毛气流传感器", 《传感技术学报》 * |
| 边义祥 等: "含金属芯压电纤维的传感特性研究", 《振动、测试与诊断》 * |
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