CN114953296B - Manufacturing method of polycrystalline polyvinylidene fluoride film and wearable device - Google Patents
Manufacturing method of polycrystalline polyvinylidene fluoride film and wearable device Download PDFInfo
- Publication number
- CN114953296B CN114953296B CN202210581109.3A CN202210581109A CN114953296B CN 114953296 B CN114953296 B CN 114953296B CN 202210581109 A CN202210581109 A CN 202210581109A CN 114953296 B CN114953296 B CN 114953296B
- Authority
- CN
- China
- Prior art keywords
- polyvinylidene fluoride
- fluoride film
- wearable device
- film
- polycrystalline
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 229920002981 polyvinylidene fluoride Polymers 0.000 title claims abstract description 156
- 239000002033 PVDF binder Substances 0.000 title claims abstract description 155
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 11
- 239000013078 crystal Substances 0.000 claims abstract description 36
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 claims description 18
- 239000000835 fiber Substances 0.000 claims description 16
- 239000000463 material Substances 0.000 claims description 15
- 238000010438 heat treatment Methods 0.000 claims description 9
- 238000001523 electrospinning Methods 0.000 claims description 8
- 230000035790 physiological processes and functions Effects 0.000 claims description 8
- 239000000758 substrate Substances 0.000 claims description 8
- 230000036760 body temperature Effects 0.000 claims description 7
- 230000029058 respiratory gaseous exchange Effects 0.000 claims description 5
- 239000002904 solvent Substances 0.000 claims description 5
- 230000036772 blood pressure Effects 0.000 claims description 3
- 239000011248 coating agent Substances 0.000 claims description 2
- 238000000576 coating method Methods 0.000 claims description 2
- 238000002360 preparation method Methods 0.000 claims description 2
- 230000000694 effects Effects 0.000 abstract description 10
- 238000000034 method Methods 0.000 description 10
- 238000010041 electrostatic spinning Methods 0.000 description 4
- 210000000707 wrist Anatomy 0.000 description 4
- 238000001816 cooling Methods 0.000 description 3
- 125000004435 hydrogen atom Chemical class [H]* 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- 230000010287 polarization Effects 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 230000006978 adaptation Effects 0.000 description 2
- 238000000137 annealing Methods 0.000 description 2
- 238000002425 crystallisation Methods 0.000 description 2
- 230000008025 crystallization Effects 0.000 description 2
- 125000001153 fluoro group Chemical group F* 0.000 description 2
- 238000012544 monitoring process Methods 0.000 description 2
- 230000002269 spontaneous effect Effects 0.000 description 2
- BAAVRTJSLCSMNM-CMOCDZPBSA-N (2s)-2-[[(2s)-2-[[(2s)-2-[[(2s)-2-amino-3-(4-hydroxyphenyl)propanoyl]amino]-4-carboxybutanoyl]amino]-3-(4-hydroxyphenyl)propanoyl]amino]pentanedioic acid Chemical compound C([C@H](N)C(=O)N[C@@H](CCC(O)=O)C(=O)N[C@@H](CC=1C=CC(O)=CC=1)C(=O)N[C@@H](CCC(O)=O)C(O)=O)C1=CC=C(O)C=C1 BAAVRTJSLCSMNM-CMOCDZPBSA-N 0.000 description 1
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 description 1
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- IUHFWCGCSVTMPG-UHFFFAOYSA-N [C].[C] Chemical group [C].[C] IUHFWCGCSVTMPG-UHFFFAOYSA-N 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 125000004432 carbon atom Chemical group C* 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 229920000131 polyvinylidene Polymers 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 108010032276 tyrosyl-glutamyl-tyrosyl-glutamic acid Proteins 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
- B29C41/24—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of indefinite length
- B29C41/30—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of indefinite length incorporating preformed parts or layers, e.g. moulding around inserts or for coating articles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
- B29C41/34—Component parts, details or accessories; Auxiliary operations
- B29C41/38—Moulds, cores or other substrates
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
- B29C41/34—Component parts, details or accessories; Auxiliary operations
- B29C41/42—Removing articles from moulds, cores or other substrates
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
- B29C41/34—Component parts, details or accessories; Auxiliary operations
- B29C41/52—Measuring, controlling or regulating
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Manufacture Of Macromolecular Shaped Articles (AREA)
- Treatments Of Macromolecular Shaped Articles (AREA)
Abstract
The invention provides a manufacturing method of a polycrystalline polyvinylidene fluoride film. The polycrystalline polyvinylidene fluoride film obtained by the manufacturing method has the beta crystal phase and the gamma crystal phase at the same time, so that the polycrystalline polyvinylidene fluoride film has good piezoelectric effect to sense pressure or tension in different directions. Meanwhile, the polycrystalline polyvinylidene fluoride film also has good pyroelectric effect for sensing ambient temperature.
Description
Technical Field
The invention relates to a method for manufacturing a polyvinylidene fluoride film (polyvinylidene difluoride; PVDF), in particular to a method for manufacturing a polycrystalline polyvinylidene fluoride film.
Background
Polyvinylidene fluoride (Polyvinylidene fluoride; PVDF) has good chemical corrosion resistance, high temperature resistance, oxidation resistance, weather resistance and radiation resistance, and also has piezoelectric effect, pyroelectric effect and dielectric effect, so that the polyvinylidene fluoride (PVDF) is widely applied to functional films such as piezoelectric films, solar backboard films, lithium battery films and the like. The piezoelectric effect is that when a piezoelectric crystal is deformed by an external force, equal amounts of different charges appear on some of its corresponding surfaces. Pyroelectric effects are phenomena in which the electrical polarization of a polar dielectric changes due to temperature changes. Pyroelectric effects can be used to measure ambient or body temperature.
Compared with the traditional piezoelectric material (such as a ceramic piezoelectric plate), the polyvinylidene fluoride has the characteristics of wide frequency response, large dynamic range, high force point conversion sensitivity, good mechanical property, high mechanical strength, easy matching of acoustic impedance and the like, and has the advantages of light weight, softness, no brittleness, impact resistance, difficult pollution by water and chemicals, easy preparation of sheets or pipes with any shape and area and the like. The method is widely applied to the technical fields of mechanics, acoustics, optics, electronics, measurement, infrared, safety alarm, medical care, military, traffic, information engineering, office automation, ocean development, geological exploration and the like.
The piezoelectric film formed by polyvinylidene fluoride has the advantages of thin thickness, light weight, very softness, capability of working under the condition of no power supply and the like, so that the piezoelectric film is widely applied to devices such as medical sensors and the like. The piezoelectric film formed by polyvinylidene fluoride is used as a dynamic strain sensor, and is very suitable for being applied to the surface of human skin or implanted into the human body for physiological state monitoring, such as respiration and heartbeat monitoring.
Polyvinylidene fluoride is a polycrystalline polymer, and polyvinylidene fluoride films with different crystalline phases can be obtained by using different methods such as additives. The crystal phases mainly comprise an alpha crystal phase, a beta crystal phase and a gamma crystal phase. Polyvinylidene fluoride in the alpha crystal phase has high thermodynamic stability, and the molecular chain conformation of TGTG' in the crystal lattice leads to opposite polarity and no polarity of the molecular chain dipole. The polyvinylidene fluoride with beta crystal phase is an orthorhombic all-trans conformation TTT, has spontaneous polarity and excellent piezoelectric performance. The molecular conformation of the gamma-crystalline polyvinylidene fluoride is TTTGTTTG', and two molecular chains in the same unit cell are arranged in parallel, and have polarity due to the same dipole moment direction. Fig. 1, 2 and 3 show the molecular structures of polyvinylidene fluoride in the alpha, beta and gamma crystalline phases, respectively, wherein C is a Carbon (Carbon) atom, F is a Fluorine (Fluorine) atom, and H is a Hydrogen (Hydrogen) atom.
The beta crystal phase and the gamma crystal phase of the polyvinylidene fluoride have higher spontaneous polarization intensity, and are important crystal phase structures of the polyvinylidene fluoride. Polyvinylidene fluoride having beta and gamma crystal phases has excellent ferroelectric, pyroelectric and piezoelectric properties.
In recent years, polyvinylidene fluoride films have also begun to be used in wearable devices. However, the existing polyvinylidene fluoride film only uses one crystal phase, has a single function, and therefore has limited application in wearable devices with limited space. Therefore, the invention provides a polycrystalline polyvinylidene fluoride film to provide multiple functions at the same time.
Disclosure of Invention
One of the objects of the present invention is to provide a method for producing a polyvinylidene fluoride film having a polycrystalline phase.
One of the objects of the present invention is to provide a wearable device using a polycrystalline polyvinylidene film.
According to the invention, the manufacturing method of the polycrystalline polyvinylidene fluoride film comprises the following steps: coating a polyvinylidene fluoride solution on a substrate to form a film, and heating the polyvinylidene fluoride solution on the substrate to a temperature above the melting point of the polyvinylidene fluoride solution to generate a first polyvinylidene fluoride film; cooling the first polyvinylidene fluoride film to obtain a second polyvinylidene fluoride film in a semi-molten state; preparing a plurality of polyvinylidene fluoride fibers with beta crystalline phases by utilizing electrostatic spinning; arranging the polyvinylidene fluoride fibers in parallel on the second polyvinylidene fluoride film to obtain a third polyvinylidene fluoride film; and carrying out heating annealing on the third polyvinylidene fluoride film at a fixed temperature to change alpha-phase crystals into gamma-phase crystals, and finally obtaining the polycrystalline polyvinylidene fluoride film with beta-phase and gamma-phase.
In one embodiment, a polyvinylidene fluoride material may be dissolved in a solvent, such as but not limited to Dimethylformamide (DMF), to prepare the polyvinylidene fluoride material solution.
In one embodiment, the step of producing the first polyvinylidene fluoride film comprises heating the polyvinylidene fluoride solution on the substrate above a melting point (e.g., 200 ℃) to produce the first polyvinylidene fluoride film.
In one embodiment, the fixed temperature may be 160 ℃.
In one embodiment, the step of producing the plurality of polyvinylidene fluoride fibers comprises electrospinning a polyvinylidene fluoride material to produce the plurality of polyvinylidene fluoride fibers.
According to the invention, a wearable device comprises a polycrystalline polyvinylidene fluoride film, a switching device and a processor. The polycrystalline polyvinylidene fluoride film has a beta crystal phase and a gamma crystal phase. The polycrystalline polyvinylidene fluoride film can sense temperature and pressure to generate a temperature sensing signal and a pressure sensing signal. The processor is coupled with the polycrystalline polyvinylidene fluoride film and the switching device, controls the switching device according to the temperature sensing signal to start or close the wearable device, and generates an electric signal according to the pressure sensing signal.
In an embodiment, when the polycrystalline polyvinylidene fluoride film senses the temperature of a human body, the processor starts the wearable device according to the temperature sensing signal.
In an embodiment, when the polycrystalline polyvinylidene fluoride film does not sense the temperature of the human body, the processor turns off the wearable device according to the temperature sensing signal.
In one embodiment, the electrical signal is used to determine a physiological state or to generate related information.
In an embodiment, the physiological state comprises heart beat, blood pressure or respiration.
In one embodiment, the related information includes pressure, weight, or distance.
Drawings
Fig. 1 shows the molecular structure of polyvinylidene fluoride in the alpha-crystalline phase.
Fig. 2 shows the molecular structure of polyvinylidene fluoride in the β -crystalline phase.
Fig. 3 shows the molecular structure of polyvinylidene fluoride in gamma-crystalline phase.
FIG. 4 shows a process for making a polycrystalline polyvinylidene fluoride film according to the present invention.
Fig. 5 shows a wearable device using the polycrystalline polyvinylidene fluoride film of the present invention.
Fig. 6 shows a first embodiment of the operation of the wearable device of fig. 5.
Fig. 7 shows a second embodiment of the operation of the wearable device of fig. 5.
Reference numerals:
wearable device 12. polycrystalline phase polyvinylidene fluoride film
Processor 16 switching device
S10. step s12. step
S14. step s16. step
S18. step s20. step
S22. step s24. step
S26. step s28. step
S29. step s30. step
S32. step s34. step
C. carbon atoms f. fluorine atoms
H. hydrogen atoms
Detailed Description
In order that the manner in which the above recited features of the present invention are attained and can be understood in detail, a more particular description of the invention, briefly summarized below, may be had by reference to embodiments, some of which are illustrated in the appended drawings. This invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. These embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
Values or ranges are recited herein that are otherwise approximate unless explicitly stated otherwise.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, and/or components.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an overly formal sense unless expressly so defined herein.
In this document, numerous specific details are set forth in order to provide a thorough understanding of the following embodiments. However, embodiments of the invention may be practiced without these specific details. In other instances, well-known structures and devices are shown schematically in order to simplify the drawings.
In various embodiments, one feature, element, or circuit may be formed on, connected to, and/or coupled to another feature, element, or circuit, and may include implementations in which the features, elements, or circuits are in contact, or may include implementations in which other features, elements, or circuits may be formed and interposed between the features, elements, or circuits, such that the features, elements, or circuits may not be in direct contact.
FIG. 4 shows a process for making a polycrystalline polyvinylidene fluoride film according to the present invention. In step S10 of fig. 4, a polyvinylidene fluoride solution is prepared, and the polyvinylidene fluoride solution is coated on a substrate to form a film, and then the polyvinylidene fluoride solution on the substrate is heated to above its melting point, so that the polyvinylidene fluoride solution is flattened into a first polyvinylidene fluoride film. The first polyvinylidene fluoride film produced in step S10 is a half melt film. The heating of the polyvinylidene fluoride solution can not only produce the first polyvinylidene fluoride film, but also eliminate the thermal history of the polyvinylidene fluoride material in the polyvinylidene fluoride solution, so that the subsequent crystallization is not influenced by the previous generation conditions. Wherein the thermal history comprises the influences of temperature, shearing, stretching and the like of the polyvinylidene fluoride material before molding and leaving a factory. In one embodiment, the polyvinylidene fluoride solution on the substrate may be heated to about 200 ℃ to obtain the first polyvinylidene fluoride film. In one embodiment, the step of formulating the polyvinylidene fluoride solution includes dissolving a polyvinylidene fluoride material in a corresponding solvent to obtain the polyvinylidene fluoride solution, wherein the solvent includes, but is not limited to, dimethylformamide (DMF).
After the production of the first polyvinylidene fluoride film is completed in step S10, step S12 of fig. 4 is performed. In step S12, the first polyvinylidene fluoride film is cooled to form a second polyvinylidene fluoride film in a semi-molten state. The second polyvinylidene fluoride film has an alpha crystalline phase. In one embodiment, the first polyvinylidene fluoride film is cooled from a temperature of about 200 ℃ to a temperature of about 160 ℃ to obtain the second polyvinylidene fluoride film. The cooling manner of step S12 includes, but is not limited to, natural cooling.
In step S14 of fig. 4, a polyvinylidene fluoride material is placed in an electrospinning apparatus for electrospinning to produce a plurality of polyvinylidene fluoride fibers having a beta crystalline phase. During electrospinning, the polyvinylidene fluoride material will be melted to eliminate the thermal history of the polyvinylidene fluoride material to avoid affecting subsequent crystallization. The electrostatic spinning is a technology for preparing fibers through a high electric field, and beta-crystalline phase of the polyvinylidene fluoride fibers prepared through the electrostatic spinning is stable and easy to prepare, mainly because stretching and solidification are carried out simultaneously when the electrostatic spinning gives electric polarization to the polyvinylidene fluoride material. Electrospinning is a common technique, so its specific operation and principle are not described here again. In the embodiment of fig. 4, the electrospinning method is used to produce a plurality of polyvinylidene fluoride fibers having a beta crystalline phase, but the present invention is not limited thereto, and other methods that can produce polyvinylidene fluoride fibers having a beta crystalline phase are also applicable to the present invention.
In the embodiment of fig. 4, the step S10 and the step S14 may be performed simultaneously, or one may be performed after the other is completed. For example, steps S10 and S12 are performed before step S14 is performed, or steps S14 are performed before steps S10 and S12 are performed.
In the embodiment of fig. 4, the polyvinylidene fluoride material in the polyvinylidene fluoride solution used in step S10 may be the same as or different from the polyvinylidene fluoride material used in step S14.
Step S16 is performed after the second polyvinylidene fluoride film and the plurality of polyvinylidene fluoride fibers are obtained. In step S16, the second polyvinylidene fluoride film is placed on a collecting table, and the plurality of polyvinylidene fluoride fibers are arranged in parallel on the second polyvinylidene fluoride film, so as to obtain a third polyvinylidene fluoride film having an α -crystal phase and a β -crystal phase. In one embodiment, the collection station may be an electrospinning collection station.
In one embodiment, after step S10 is completed to obtain the first polyvinylidene fluoride film, the first polyvinylidene fluoride film may be transferred to the collection table, during which transfer the first polyvinylidene fluoride film has sufficient time to cool naturally to form the second polyvinylidene fluoride film in a semi-molten state.
After the third polyvinylidene fluoride film is obtained, step S18 is performed. In step S18 of fig. 4, the third polyvinylidene fluoride film is placed on a heating table, and is heat annealed at a fixed temperature. In the heating annealing process of step S18, since the third polyvinylidene fluoride film has the polyvinylidene fluoride fiber with the β crystal phase, the α crystal in the third polyvinylidene fluoride film will be transformed into the γ crystal, and a polycrystalline polyvinylidene fluoride film with the β crystal phase and the γ crystal phase is produced. In one embodiment, the fixed temperature used in step S18 is about 160℃and the duration of heating is about 48 hours.
The polycrystalline polyvinylidene fluoride film has beta crystal phase and gamma crystal phase, and the arrangement of the beta crystal phase and the gamma crystal phase forms an included angle of 90 ℃, so that the polycrystalline polyvinylidene fluoride film has good piezoelectric effect in different directions (such as d31 and d 33). In other words, when the polycrystalline polyvinylidene fluoride film of the present invention is applied to a ring-shaped wearable device, it is possible to sense pressure or tension in various directions. In addition, the polycrystalline polyvinylidene fluoride film of the invention can also achieve temperature sensing because the beta crystal phase and the gamma crystal phase have pyroelectric effects. In the wearable device, the temperature sensing function of the poly-phase polyvinylidene fluoride film can be used for sensing the temperature of a human body, and when the poly-phase polyvinylidene fluoride film senses the body temperature or the sensed temperature is higher than a preset value, the wearable device is started. In contrast, when the poly-phase polyvinylidene fluoride film does not sense the body temperature or the sensed temperature is lower than a preset value, the wearable device is turned off. The function of automatically starting and closing the wearable device can avoid the power waste caused by the fact that a user forgets to close the wearable device, and the service life of the wearable device can be prolonged.
Fig. 5 shows a wearable device 10 using the polycrystalline polyvinylidene fluoride film 12 of the present invention. In the embodiment of fig. 5, the wearable device 10 includes a polycrystalline polyvinylidene fluoride film 12, a processor 14, and a switching device 16. The poly-phase polyvinylidene fluoride film 12 has both a beta-phase and a gamma-phase. The processor 14 is connected to the poly-phase polyvinylidene fluoride film 12 and the switching device 16. The switch device 16 is used to control the on/off of the wearable device 10. The wearable device 10 may be, but is not limited to, a pulse sensor.
The processor 14 of fig. 5 may be a machine utilizing hardware, firmware, and/or software, and is physically adapted to operate via brin logic (or boolean logic) on a plurality of logic gates forming a specific physical circuit to perform specific tasks defined by executable machine instructions. A processor may use mechanical, pneumatic, hydraulic, electrical, magnetic, optical, information, chemical, and/or biological principles, mechanisms, adaptations, signals, inputs, and/or outputs to perform tasks. The processor may be a general purpose device such as a microcontroller and/or microprocessor. In some embodiments, the processor may be a special purpose device, such as an Application Specific Integrated Circuit (ASIC) or Field Programmable Gate Array (FPGA).
The switching device 16 of fig. 5 is an on/off circuit for cutting off or conducting a current path. In one embodiment, switching device 16 may be, but is not limited to, a switch formed of a single transistor.
Fig. 6 shows a first embodiment of the operation of the wearable device 10 of fig. 5. As shown in steps S20 and S22 of fig. 6, when the user wears the wearable device 10 on the wrist, the poly-phase polyvinylidene fluoride film 12 of the wearable device 10 senses the body temperature of the user, and the poly-phase polyvinylidene fluoride film 12 thus outputs a temperature sensing signal to the processor 14. After the processor 14 receives the temperature sensing signal from the poly-phase polyvinylidene fluoride film 12, the processor 14 controls the switching device 16 to activate the wearable device 10, as shown in step S24 of fig. 6. When the user removes the wearable device 10, the poly-phase polyvinylidene fluoride film 12 of the wearable device 10 cannot sense the body temperature of the user, so the poly-phase polyvinylidene fluoride film 12 stops outputting the temperature sensing signal to the processor 14, as shown in steps S26 and S28 of fig. 6. After the poly-phase polyvinylidene fluoride film 12 stops outputting the temperature sensing signal, the processor 14 controls the switching device 16 to turn off the wearable device 10, as shown in step S29 of fig. 6.
Fig. 7 shows a second embodiment of the operation of the wearable device 10 of fig. 5. When the user wears the wearable device 10 on the wrist, the poly-phase polyvinylidene fluoride film 12 of the wearable device 10 may sense the pressure or tension on the wrist, as shown in step S30 of fig. 7. The pressure or tension on the wrist is from the pulse beat or the swing of the arm. Based on the sensed pressure or tension, the poly-phase polyvinylidene fluoride film 12 generates a pressure sensing signal to the processor 14. The processor 14 determines an electrical signal according to the pressure sensing signal, as shown in step S32. The wearable device 10 determines the physiological status of the user or generates related information according to the electrical signal. Finally, the wearable device 10 can feed back the obtained physiological status or related information to the user, as shown in step S34. The feedback to the user may include, but is not limited to, displaying the physiological status or related information on a display, which may be provided on the wearable device 10 or externally connected thereto. Depending on the type of wearable device 10, the physiological state obtained by the wearable device 10 may be different, for example, when the wearable device 10 is a pulse sensor, the physiological state may be the heartbeat or blood pressure of the user. When the wearable device 10 is a respiration sensor, the physiological state may be the respiration of the user. Also, depending on the type of the wearable device 10, the related information obtained by the wearable device 10 may be, but is not limited to, pressure, weight or distance.
The foregoing description is only illustrative of the present invention and is not to be construed as limiting the invention, but is not to be construed as limiting the invention, and any and all simple modifications, equivalent variations and adaptations of the foregoing embodiments, which are within the scope of the invention, may be made by those skilled in the art without departing from the scope of the invention.
Claims (8)
1. The manufacturing method of the polycrystalline polyvinylidene fluoride film is characterized by comprising the following steps of:
coating a polyvinylidene fluoride solution on a substrate to form a film, and heating the polyvinylidene fluoride solution on the substrate to 200 ℃ to generate a first polyvinylidene fluoride film;
the preparation step of the polyvinylidene fluoride solution comprises dissolving a polyvinylidene fluoride material in a corresponding solvent to obtain the polyvinylidene fluoride solution, wherein the solvent comprises but is not limited to Dimethylformamide (DMF);
the first polyvinylidene fluoride film is cooled from the temperature of 200 ℃ to the temperature of 160 ℃ to obtain a second polyvinylidene fluoride film in a semi-molten state;
producing a plurality of polyvinylidene fluoride fibers having a beta crystalline phase;
arranging the polyvinylidene fluoride fibers in parallel on the second polyvinylidene fluoride film to obtain a third polyvinylidene fluoride film with alpha crystal phase and beta crystal phase; and
the third polyvinylidene fluoride film was heat annealed at a fixed temperature of 160 ℃ for a heating time of 48 hours to produce the polycrystalline polyvinylidene fluoride film having a beta crystal phase and a gamma crystal phase.
2. The method of making of claim 1, wherein the step of producing the plurality of polyvinylidene fluoride fibers comprises electrospinning a polyvinylidene fluoride material to produce the plurality of polyvinylidene fluoride fibers.
3. A wearable device, comprising:
the poly-phase polyvinylidene fluoride film of claim 1, the poly-phase polyvinylidene fluoride film sensing temperature and pressure producing temperature sensing signals and pressure sensing signals;
a switching device; and
the processor is coupled with the polycrystalline polyvinylidene fluoride film and the switching device, controls the switching device to start or close the wearable device according to the temperature sensing signal, and generates an electric signal according to the pressure sensing signal.
4. The wearable device of claim 3, wherein the processor activates the wearable device according to the temperature sensing signal when the polycrystalline polyvinylidene fluoride film senses a human body temperature.
5. The wearable device of claim 3, wherein the processor turns off the wearable device according to the temperature sensing signal when the poly-phase polyvinylidene fluoride film does not sense a human body temperature.
6. The wearable device of claim 3, wherein the electrical signal is used to determine a physiological state or generate related information.
7. The wearable device of claim 6, wherein the physiological state comprises heart beat, blood pressure, or respiration.
8. The wearable device of claim 6, wherein the related information comprises pressure, weight, or distance.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210581109.3A CN114953296B (en) | 2022-05-26 | 2022-05-26 | Manufacturing method of polycrystalline polyvinylidene fluoride film and wearable device |
| TW111120191A TWI828170B (en) | 2022-05-26 | 2022-05-31 | Fabrication method of polycrystalline phase polyvinylidene fluoride film and wearable device using polycrystalline phase polyvinylidene fluoride film |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210581109.3A CN114953296B (en) | 2022-05-26 | 2022-05-26 | Manufacturing method of polycrystalline polyvinylidene fluoride film and wearable device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114953296A CN114953296A (en) | 2022-08-30 |
| CN114953296B true CN114953296B (en) | 2023-08-29 |
Family
ID=82955622
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210581109.3A Active CN114953296B (en) | 2022-05-26 | 2022-05-26 | Manufacturing method of polycrystalline polyvinylidene fluoride film and wearable device |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN114953296B (en) |
| TW (1) | TWI828170B (en) |
Citations (22)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4308370A (en) * | 1979-04-26 | 1981-12-29 | Rikagauku Kenkyusho | Piezoelectric and pyroelectric polymer film and process for preparing same |
| ITMI972764A1 (en) * | 1997-12-15 | 1999-06-15 | Ausimont Spa | FLUORINATED THERMOPLASTIC ELASTOMERS |
| US5922493A (en) * | 1995-03-03 | 1999-07-13 | Elf Atochem North America, Inc. | Polymeric electrode and electrolyte article of manufacture |
| KR20090030827A (en) * | 2007-09-21 | 2009-03-25 | 경희대학교 산학협력단 | Method for producing polyvinylidene fluoride nanofiber web containing a large amount of β-crystal having excellent piezoelectricity |
| KR20090131313A (en) * | 2008-06-18 | 2009-12-29 | 연세대학교 산학협력단 | Β Crystallization Method of PFCDF Thin Films Cast Through RTA |
| CN102805615A (en) * | 2012-07-26 | 2012-12-05 | 翁整 | A vital sign monitoring alarm based on smart phone application |
| CN104291264A (en) * | 2014-10-17 | 2015-01-21 | 华中科技大学 | Nano-piezoelectric fiber based flexible energy-harvesting device and manufacturing method thereof |
| CN105385077A (en) * | 2015-12-21 | 2016-03-09 | 中国科学院长春应用化学研究所 | Polyvinylidene fluoride composite material, preparation method and applications thereof |
| CN105739612A (en) * | 2014-12-30 | 2016-07-06 | 意美森公司 | Deformable Haptic Wearables With Variable Physical Properties |
| CN105758452A (en) * | 2016-02-04 | 2016-07-13 | 歌尔声学股份有限公司 | Wearing state detection method and device of wearable equipment |
| JP2016160307A (en) * | 2015-02-27 | 2016-09-05 | 公立大学法人大阪市立大学 | Method for producing polyvinylidene fluoride film |
| KR20160147446A (en) * | 2015-06-15 | 2016-12-23 | 서울시립대학교 산학협력단 | manufacture method of bulletproof glass using ferroelectrics |
| KR101840136B1 (en) * | 2016-11-10 | 2018-03-20 | 중앙대학교 산학협력단 | Manufacturing method for PVDF based film and fiber with an increased β-phase ratio |
| CN109686836A (en) * | 2018-11-27 | 2019-04-26 | 江苏大学 | A kind of preparation method of the 3D printing poly meta fluoroethylene piezoelectric film under uniform electric field |
| CN110752286A (en) * | 2019-10-25 | 2020-02-04 | 业成科技（成都）有限公司 | Piezoelectric film, preparation method thereof and piezoelectric film sensor |
| CN111166304A (en) * | 2019-12-31 | 2020-05-19 | 青岛理工大学 | Medical care health flexible sensor detection system |
| CN112745519A (en) * | 2019-10-31 | 2021-05-04 | 北京化工大学 | Preparation method of polyvinylidene fluoride film |
| CN113336986A (en) * | 2021-06-03 | 2021-09-03 | 陕西科技大学 | Preparation method of oriented gamma-phase PVDF/CTAB composite film |
| CN214667279U (en) * | 2021-05-14 | 2021-11-09 | 深圳市三五智能科技有限公司 | Wearable intelligent body temperature monitoring device |
| JP2021176629A (en) * | 2020-05-01 | 2021-11-11 | 三菱ケミカル株式会社 | Resin composition manufacturing method, porous film manufacturing method, and porous film |
| CN113659069A (en) * | 2021-05-08 | 2021-11-16 | 西华大学 | High-performance PVDF (polyvinylidene fluoride) -based flexible piezoelectric device based on MXene and micro injection molding and preparation method thereof |
| CN113801413A (en) * | 2021-11-02 | 2021-12-17 | 北京航空航天大学 | Photosensitive ferroelectric polymer composite film, method for preparing the same, and ferroelectric device or piezoelectric device using the same |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20160016369A1 (en) * | 2014-05-21 | 2016-01-21 | University Of South Carolina | Novel Additive Manufacturing-Based Electric Poling Process of PVDF Polymer for Piezoelectric Device Applications |
| KR101810545B1 (en) * | 2014-09-09 | 2017-12-19 | 사빅 글로벌 테크놀러지스 비.브이. | Methods for producing a thin film ferroelectric device using a two-step temperature process |
| TWI614386B (en) * | 2015-03-11 | 2018-02-11 | National Taiwan University Of Science And Technology | Acoustic absorbing material |
| WO2021168750A1 (en) * | 2020-02-27 | 2021-09-02 | 南昌欧菲显示科技有限公司 | Piezoelectric film and preparation method therefor, and piezoelectric film sensor |
| CN113261841A (en) * | 2021-03-19 | 2021-08-17 | 武汉理工大学 | Noise reduction and power generation curtain based on flexible composite phonon structure |
-
2022
- 2022-05-26 CN CN202210581109.3A patent/CN114953296B/en active Active
- 2022-05-31 TW TW111120191A patent/TWI828170B/en active
Patent Citations (22)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4308370A (en) * | 1979-04-26 | 1981-12-29 | Rikagauku Kenkyusho | Piezoelectric and pyroelectric polymer film and process for preparing same |
| US5922493A (en) * | 1995-03-03 | 1999-07-13 | Elf Atochem North America, Inc. | Polymeric electrode and electrolyte article of manufacture |
| ITMI972764A1 (en) * | 1997-12-15 | 1999-06-15 | Ausimont Spa | FLUORINATED THERMOPLASTIC ELASTOMERS |
| KR20090030827A (en) * | 2007-09-21 | 2009-03-25 | 경희대학교 산학협력단 | Method for producing polyvinylidene fluoride nanofiber web containing a large amount of β-crystal having excellent piezoelectricity |
| KR20090131313A (en) * | 2008-06-18 | 2009-12-29 | 연세대학교 산학협력단 | Β Crystallization Method of PFCDF Thin Films Cast Through RTA |
| CN102805615A (en) * | 2012-07-26 | 2012-12-05 | 翁整 | A vital sign monitoring alarm based on smart phone application |
| CN104291264A (en) * | 2014-10-17 | 2015-01-21 | 华中科技大学 | Nano-piezoelectric fiber based flexible energy-harvesting device and manufacturing method thereof |
| CN105739612A (en) * | 2014-12-30 | 2016-07-06 | 意美森公司 | Deformable Haptic Wearables With Variable Physical Properties |
| JP2016160307A (en) * | 2015-02-27 | 2016-09-05 | 公立大学法人大阪市立大学 | Method for producing polyvinylidene fluoride film |
| KR20160147446A (en) * | 2015-06-15 | 2016-12-23 | 서울시립대학교 산학협력단 | manufacture method of bulletproof glass using ferroelectrics |
| CN105385077A (en) * | 2015-12-21 | 2016-03-09 | 中国科学院长春应用化学研究所 | Polyvinylidene fluoride composite material, preparation method and applications thereof |
| CN105758452A (en) * | 2016-02-04 | 2016-07-13 | 歌尔声学股份有限公司 | Wearing state detection method and device of wearable equipment |
| KR101840136B1 (en) * | 2016-11-10 | 2018-03-20 | 중앙대학교 산학협력단 | Manufacturing method for PVDF based film and fiber with an increased β-phase ratio |
| CN109686836A (en) * | 2018-11-27 | 2019-04-26 | 江苏大学 | A kind of preparation method of the 3D printing poly meta fluoroethylene piezoelectric film under uniform electric field |
| CN110752286A (en) * | 2019-10-25 | 2020-02-04 | 业成科技（成都）有限公司 | Piezoelectric film, preparation method thereof and piezoelectric film sensor |
| CN112745519A (en) * | 2019-10-31 | 2021-05-04 | 北京化工大学 | Preparation method of polyvinylidene fluoride film |
| CN111166304A (en) * | 2019-12-31 | 2020-05-19 | 青岛理工大学 | Medical care health flexible sensor detection system |
| JP2021176629A (en) * | 2020-05-01 | 2021-11-11 | 三菱ケミカル株式会社 | Resin composition manufacturing method, porous film manufacturing method, and porous film |
| CN113659069A (en) * | 2021-05-08 | 2021-11-16 | 西华大学 | High-performance PVDF (polyvinylidene fluoride) -based flexible piezoelectric device based on MXene and micro injection molding and preparation method thereof |
| CN214667279U (en) * | 2021-05-14 | 2021-11-09 | 深圳市三五智能科技有限公司 | Wearable intelligent body temperature monitoring device |
| CN113336986A (en) * | 2021-06-03 | 2021-09-03 | 陕西科技大学 | Preparation method of oriented gamma-phase PVDF/CTAB composite film |
| CN113801413A (en) * | 2021-11-02 | 2021-12-17 | 北京航空航天大学 | Photosensitive ferroelectric polymer composite film, method for preparing the same, and ferroelectric device or piezoelectric device using the same |
Non-Patent Citations (1)
| Title |
|---|
| Flexoelectric and ferroelectric properties of quenched polyvinylidene fluoride (PVDF) homopolymer films;Lovinger, A.J.;Journal of Polymer Science;第18卷(第4期);第793-809页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114953296A (en) | 2022-08-30 |
| TW202346437A (en) | 2023-12-01 |
| TWI828170B (en) | 2024-01-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Zhu et al. | Flexible 3D architectured piezo/thermoelectric bimodal tactile sensor array for E‐skin application | |
| Liu et al. | Recent progress on flexible nanogenerators toward self‐powered systems | |
| Wang et al. | Stretchable and shape‐adaptable triboelectric nanogenerator based on biocompatible liquid electrolyte for biomechanical energy harvesting and wearable human–machine interaction | |
| Zhu et al. | A flexible active dual-parameter sensor for sensitive temperature and physiological signal monitoring via integrating thermoelectric and piezoelectric conversion | |
| Liu et al. | Strong tough thermogalvanic hydrogel thermocell with extraordinarily high thermoelectric performance | |
| Mondal et al. | Advanced pyroelectric materials for energy harvesting and sensing applications | |
| Chen et al. | Electrospun flexible PVDF/GO piezoelectric pressure sensor for human joint monitoring | |
| Yao et al. | Recent progress on the fabrication and applications of flexible ferroelectric devices | |
| Liu et al. | High p-and n-type thermopowers in stretchable self-healing ionogels | |
| Yuan et al. | Melt-stretched poly (vinylidene fluoride)/zinc oxide nanocomposite films with enhanced piezoelectricity by stress concentrations in piezoelectric domains for wearable electronics | |
| CN114953296B (en) | Manufacturing method of polycrystalline polyvinylidene fluoride film and wearable device | |
| Li et al. | Ultrasensitive mechanical/thermal response of a P (VDF-TrFE) sensor with a tailored network interconnection interface | |
| US20190023817A1 (en) | Ferroelectric polymers from dehydrofluorinated PVDF | |
| Bae et al. | Multi-deformable piezoelectric energy nano-generator with high conversion efficiency for subtle body movements | |
| KR20160053079A (en) | A piezoelectric fiber, a preparation method thereof, and textile, clothing and a wearable piezoelectric sensor using the fiber | |
| Tian et al. | Ultrathin Epidermal P (VDF-TRFE) piezoelectric film for wearable electronics | |
| Zabek et al. | Characterization and modeling of meshed electrodes on free standing polyvilylidene difluoride (PVDF) films for enhanced pyroelectric energy harvesting | |
| Chai et al. | Integrated Piezoelectric/Pyroelectric Sensing from Organic–Inorganic Perovskite Nanocomposites | |
| US10584189B2 (en) | Ferroelectric polymers from dehydrofluorinated PVDF | |
| JP3470471B2 (en) | Polymer electret material and method for producing the same | |
| Wang et al. | PVDF energy-harvesting devices: Film preparation, electric poling, energy-harvesting efficiency | |
| Yuan et al. | Highly stretchable piezoelectric strain sensor with dual wavy structures of PVDF microfibers | |
| Wang et al. | Flexible piezoelectric sensor with a sandwich structure composed of ionic conductive hydrogel and PVDF film | |
| CN112928199B (en) | High-sensitivity flexible sensor and preparation method and application thereof | |
| Jayakrishnan et al. | Pyroelectric nanogenerators in energy technology |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20240111 Address after: 518109, Building E4, 101, Foxconn Industrial Park, No. 2 East Ring 2nd Road, Fukang Community, Longhua Street, Longhua District, Shenzhen City, Guangdong Province (formerly Building 1, 1st Floor, G2 District), H3, H1, and H7 factories in K2 District, North Shenchao Optoelectronic Technology Park, Minqing Road, Guangdong Province Patentee after: INTERFACE OPTOELECTRONICS (SHENZHEN) Co.,Ltd. Patentee after: Interface Technology (Chengdu) Co., Ltd. Patentee after: GENERAL INTERFACE SOLUTION Ltd. Address before: No.689 Hezuo Road, West District, high tech Zone, Chengdu City, Sichuan Province Patentee before: Interface Technology (Chengdu) Co., Ltd. Patentee before: INTERFACE OPTOELECTRONICS (SHENZHEN) Co.,Ltd. Patentee before: Yicheng Photoelectric (Wuxi) Co.,Ltd. Patentee before: GENERAL INTERFACE SOLUTION Ltd. |