Piezoelectric polymer crystallization equipment

Abstract

The utility model discloses piezoelectric polymer crystallization equipment which comprises an equipment body and a high-frequency power supply, an upper polar plate is arranged above the equipment body; a lower polar plate is arranged below the equipment body; one end of the high-frequency power supply is electrically connected to the upper polar plate, and the other end of the high-frequency power supply is electrically connected to the lower polar plate; a polymer solution is arranged in the equipment body; the high-frequency heating PVDF piezoelectric polymer solvent crystallization equipment has the advantages of uniform temperature, high heating speed, convenience in reaction control, heating selectivity and the like, dipoles in the solvent are oriented and polarized under the action of a high-frequency alternating electric field to form a temperature gradient (high inside and low outside), so that the solvent is promoted to be volatilized and dried from inside to outside, and meanwhile, vacuum high-frequency heating can be matched, so that the crystallization efficiency is improved. The boiling point of the solvent can be reduced within a certain vacuum degree, and meanwhile, in a negative pressure environment, the pressure in the solution is greater than the surface, so that the diffusion speed of the solvent from inside to outside is accelerated.

Description

Technical Field

[0001] The present invention relates to the technical field of piezoelectric polymer crystallization, and more particularly to a piezoelectric polymer crystallization device. Background Art

[0002] Polyvinylidene fluoride (PVDF) is a semicrystalline polymer with five main crystalline structures (α, β, γ, δ, and ε). The β crystal has a higher polarity, a higher dielectric constant, and a higher piezoelectric coefficient. Therefore, the β crystal is the most important crystalline form of PVDF polymer used in sensing technology. PVDF crystallizes from solution and typically only produces the non-polar α crystal with a helical conformation. However, the PVDF-TrFE copolymer, obtained by copolymerizing vinylidene fluoride and trifluoroethylene, can directly form the β crystal with an all-trans conformation when crystallized.

[0003] Crystallization of PVDF and its polymers typically occurs during the melt cooling process, or is induced by solvent volatilization, i.e., a change in solution temperature. In the prior art, PVDF and its polymers typically utilize heating methods such as heat conduction, heat radiation, and heat convection during solvent volatilization or melt cooling crystallization.

[0004] In the prior art, piezoelectric polymers are heated by heat conduction, heat radiation, and heat convection during the crystallization process from solution. The heat first acts on the interface of the solution, causing the solvent on the surface to evaporate preferentially before the solvent inside the solution is fully evaporated. This, to a certain extent, hinders the outward evaporation of the internal solvent, resulting in a piezoelectric film with high porosity, an opaque appearance (milky white), and brittle appearance.

[0005] In the existing technology, during the crystallization process of piezoelectric polymer from solution, heat needs to first pass through the substrate coated with the piezoelectric polymer solution and then act on the solution, which can easily cause thermal deformation of some substrates (including flexible substrates, glass substrates or silicon-based substrates, etc.), and even cause delamination of the substrate and the piezoelectric film after solidification and crystallization. Summary of the Invention

[0006] In order to solve at least one of the above technical problems, the present invention provides a piezoelectric polymer crystallization device.

[0007] A first aspect of the present invention provides a piezoelectric polymer crystallization device, comprising: a device body and a high-frequency power supply;

[0008] An upper electrode plate is provided above the device body;

[0009] A lower electrode plate is provided below the device body;

[0010] One end of the high-frequency power supply is electrically connected to the upper plate, and the other end of the high-frequency power supply is electrically connected to the lower plate;

[0011] A polymer solution is arranged inside the device body.

[0012] In a preferred embodiment of the present invention, the present invention further comprises a substrate, and the polymer solution is evenly coated on the substrate.

[0013] In a preferred embodiment of the present invention, the substrate includes one of a flexible substrate, a wafer substrate or a glass substrate.

[0014] In a preferred embodiment of the present invention, the polymer solution includes polyvinylidene fluoride or polyvinylidene fluoride polymer.

[0015] In a preferred embodiment of the present invention, a good solvent is further included. The good solvent is disposed inside the device body and is added to the polymer solution.

[0016] In a preferred embodiment of the present invention, the good solvent includes methyl ethyl ketone or dimethylformamide.

[0017] In a preferred embodiment of the present invention, the dielectric constant of the methyl ethyl ketone is 18.5, the dielectric loss of the methyl ethyl ketone is 1.462, the dielectric constant of the dimethylformamide is 37.7, and the dielectric loss of the dimethylformamide is 60.7.

[0018] The above technical solution of the present invention has the following advantages over the prior art:

[0019] This application utilizes high-frequency heating for PVDF piezoelectric polymer solvent crystallization, which offers advantages such as uniform temperature, fast heating speed, convenient reaction control, and heating selectivity. Under the action of a high-frequency alternating electric field, the internal dipoles of the solvent are polarized, forming a temperature gradient (high inside, low outside), thereby driving the solvent to evaporate and dry from the inside out. This can also be combined with vacuum high-frequency heating, which, within a certain vacuum level, can lower the boiling point of the solvent. Furthermore, in a negative pressure environment, the pressure inside the solution is greater than the surface, which helps accelerate the diffusion of the solvent from the inside out. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the specific embodiments or the description of the prior art. Obviously, some of the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 This is a diagram of a piezoelectric polymer crystallization device according to an embodiment of the present invention.

[0022] In the figure: 1. Upper plate, 2. Lower plate, 3. Polymer solution, 4. High-frequency power supply, 5. Device body, 6. Wires. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of this application.

[0024] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0025] In this application, terms such as "upper," "lower," "left," "right," "front," "back," "top," "bottom," "inner," "outer," "center," "vertical," "horizontal," "transverse," and "longitudinal" indicate positions or locations based on the positions or locations shown in the accompanying drawings. These terms are primarily intended to better describe the present invention and its embodiments and are not intended to limit the devices, elements, or components indicated to having a specific orientation, or to being constructed or operated in a specific orientation.

[0026] Furthermore, some of the above terms may be used to express other meanings besides indicating a position or location. For example, the term "on" may also be used to indicate a dependency or connection in certain circumstances. Those skilled in the art will understand the specific meanings of these terms in the present invention based on the specific circumstances.

[0027] Furthermore, the terms "installed," "disposed," "provided with," "connected," "connected," and "socketed" should be interpreted broadly. For example, they can refer to fixed connections, removable connections, or integral structures; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; or internal communication between two devices, elements, or components. Those skilled in the art will understand the specific meanings of these terms in the present invention based on specific circumstances.

[0028] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0029] Example 1

[0030] See also Figure 1 As shown, the present invention proposes a piezoelectric polymer crystallization device, including: a device body 5 and a high-frequency power supply 4; an upper electrode plate 1 is arranged above the device body 5; a lower electrode plate 2 is arranged below the device body 5; one end of the high-frequency power supply 4 is electrically connected to the upper electrode plate 1, and the other end of the high-frequency power supply 4 is electrically connected to the lower electrode plate 2; a polymer solution 3 is arranged inside the device body 5.

[0031] Specifically, the high-frequency power supply 4 is connected to the upper electrode plate 1 and the lower electrode plate 2 through the wire 6, and the dielectric is heated from the inside of the solution by the principle of oriented polarization heating under the action of the alternating electromagnetic field. Heat is generated from various places inside the solution, and the solvent is fully and evenly evaporated from the inside to the outside, which solves the problem of insufficient and uneven solvent volatilization in the traditional solution crystallization process of the piezoelectric polymer film. Therefore, the crystallinity of the piezoelectric film can be made more uniform, and the density and crystallinity of the film can be improved.

[0032] According to an embodiment of the present invention, a substrate is further included, and the polymer solution 3 is evenly coated on the substrate. The substrate includes one of a flexible substrate, a wafer substrate, or a glass substrate.

[0033] According to an embodiment of the present invention, the polymer solution 3 includes polyvinylidene fluoride or a polyvinylidene fluoride polymer.

[0034] According to an embodiment of the present invention, a good solvent is further included. The good solvent is disposed inside the device body 5 and is added into the polymer solution 3 .

[0035] According to an embodiment of the present invention, the good solvent includes methyl ethyl ketone or dimethylformamide.

[0036] Specifically, PVDF and its polymers have many good solvents, such as polar solvents such as methyl ethyl ketone (MEK) and dimethylformamide (DMF). Evaporating the solvent from the solution can achieve crystallization of PVDF and its polymers. Using an alternating electromagnetic field to heat the volatile polar solvent can be explained by the interaction between the substance and the alternating electromagnetic field. Under the action of the alternating electromagnetic field, molecules containing dipole moments try to align with the rapidly changing electric field, resulting in the deflection and movement of the dipoles. This movement generates kinetic energy, which is converted into heat energy.

[0037] According to an embodiment of the present invention, the dielectric constant of methyl ethyl ketone is 18.5, the dielectric loss of methyl ethyl ketone is 1.462, the dielectric constant of dimethylformamide is 37.7, and the dielectric loss of dimethylformamide is 60.7.

[0038] During the solution crystallization process, high-frequency alternating heating is used. Heat is generated from within the solution, allowing the solution in the electric field to be heated uniformly, reaching the same temperature from the inside out, thereby improving film density. High-frequency alternating heating facilitates reaction control: heating occurs when power is on and stops when power is off, allowing instantaneous heating control by adjusting the time. Furthermore, because different objects have different dissipation factors and absorb different electric field energies at a certain frequency, the appropriate frequency can be selected to heat a specific substance within the electric field, allowing for selective heating and reducing energy consumption. High-frequency heating PVDF piezoelectric polymer solvent crystallization equipment offers advantages such as uniform temperature, fast heating, convenient reaction control, and selective heating.

[0039] In summary, the present application is suitable for coating PVDF polymer solution 3 on various flexible, wafer, glass and other substrates, applying a high-frequency alternating electric field of a certain frequency, and the applied electric field energy is selectively lost by the solvent, and the solvent evaporates from the inside to the outside. The flexible substrate, wafer substrate, glass substrate and the devices thereon do not suffer losses, and will not cause thermal deformation, thermal delamination, etc. The present application adopts high-frequency heating PVDF piezoelectric polymer solvent crystallization equipment with the advantages of uniform temperature, fast heating speed, convenient reaction control, and heating selectivity. Under the action of the high-frequency alternating electric field, the internal dipole orientation of the solvent is polarized to form a temperature gradient (high inside and low outside), thereby promoting the solvent to evaporate and dry from the inside to the outside. At the same time, it can be combined with vacuum high-frequency heating. Within a certain vacuum degree, the boiling point of the solvent can be reduced. At the same time, in a negative pressure environment, the pressure inside the solution is greater than the surface, which is conducive to accelerating the diffusion rate of the solvent from the inside to the outside.

[0040] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to the above embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein, but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

[0041] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A piezoelectric polymer crystallization device comprising: The device body and high-frequency power supply are characterized in that: An upper electrode plate is provided above the device body; A lower electrode plate is provided below the device body; One end of the high-frequency power supply is electrically connected to the upper plate, and the other end of the high-frequency power supply is electrically connected to the lower plate; A polymer solution is arranged inside the device body.

2. A piezoelectric polymer crystallization device according to claim 1, characterized in that: The invention also includes a substrate, on which the polymer solution is evenly coated.

3. A piezoelectric polymer crystallization device according to claim 2, characterized in that: The substrate includes one of a flexible substrate, a wafer substrate or a glass substrate.

4. The piezoelectric polymer crystallization device according to claim 1, characterized in that: The polymer solution includes polyvinylidene fluoride or a polyvinylidene fluoride polymer.

5. The piezoelectric polymer crystallization device according to claim 1, characterized in that: The device further comprises a good solvent, which is arranged inside the device body and is added into the polymer solution.

6. The piezoelectric polymer crystallization device according to claim 5, characterized in that: The good solvent includes methyl ethyl ketone or dimethylformamide.

7. The piezoelectric polymer crystallization device according to claim 6, characterized in that: The dielectric constant of the methyl ethyl ketone is 18.5, and the dielectric loss of the methyl ethyl ketone is 1.

462. The dielectric constant of the dimethylformamide is 37.7, and the dielectric loss of the dimethylformamide is 60.7.

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