JP2009273204A - Polymer flexible actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polymer flexible actuator using a dielectric polymer that is driven by a low electric field. <P>SOLUTION: A polymer flexible actuator contains a dielectric polymer, a plasticizer, and a gel 1 consisting of ion liquid selected from phosphonium based cation and ammonium based cation. Preferably, the dielectric polymer is polyvinyl chloride. Preferably, the plasticizer is adipic acid, sebacic acid, itaconic acid or phthalic ester. Furthermore, the polymer flexible actuator preferably contains 1-50 pts.wt. of dielectric polymer, 50-150 pts.wt. of plasticizer, and 1-30 pts.wt. of ion liquid. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a polymer flexible actuator that can be applied to artificial muscles and the like, can be deformed by electrical stimulation, and is small, flexible, and lightweight.

  Actuators using dielectric polymer materials are small, light and flexible, and are expected to be applied to artificial muscles. Examples of dielectric polymer materials expected as artificial muscle actuators include polyvinyl chloride and polymethyl methacrylate. Among them, the polyvinyl chloride gel containing a plasticizer is similar to biological muscles and causes creep deformation or bending deformation by electrical stimulation. However, in general, driving a gel actuator using these dielectric polymers requires application of a high voltage of several hundred volts. Therefore, the development of a gel actuator driven at a low voltage is indispensable for application to artificial muscles.

  In order to solve these problems, in recent years, an ion gel actuator using a polymer and an ionic liquid has attracted attention.

  Patent Document 1 discloses an actuator using a polymer and an ionic liquid. This uses a dielectric polymer, an ionic liquid, and carbon nanofibers. This actuator is formed of three layers, the manufacturing method requires several steps, and the reagents used are generally expensive.

The actuator of Patent Document 2 is an actuator using a dielectric polymer, a plasticizer, and an additive, and discloses a method for reducing the drive voltage. In this driving method, although the driving voltage is lowered as compared with the conventional method, an applied voltage of 100 V or more is necessary, and there is a second point that requires a relatively high driving voltage.
JP 2006-288040 JP-A-2005-323482

  An object of the present invention is to provide a flexible polymer actuator that can be driven in a low electric field, operates stably in air, is extremely simple to manufacture and process, and enables practical application to a wide range of applications.

  The polymer flexible actuator according to claim 1, which has been made to achieve the above object, includes a dielectric polymer, a plasticizer, and an on-liquid selected from a phosphonium cation and an ammonium cation. It consists of a gel.

  A polymer flexible actuator according to a second aspect is the one according to the first aspect, wherein the dielectric polymer is polyvinyl chloride.

  A flexible polymer actuator according to a third aspect is the polymer flexible actuator according to the first aspect, wherein the plasticizer is adipic acid, sebacic acid, itaconic acid, and phthalic acid ester.

  The flexible polymer actuator according to claim 4 is the flexible polymer actuator according to claim 1, wherein 1 to 50 parts by weight of the dielectric polymer, 50 to 150 parts by weight of the plasticizer, and 1 to 30 of the ionic liquid. It includes a weight part.

  The method for producing a flexible polymer actuator according to claim 5 comprises dissolving a dielectric polymer and a plasticizer in an organic solvent, mixing an ionic liquid therein, evaporating the organic solvent, and forming a gel. Features.

  A method for producing a flexible polymer actuator according to a sixth aspect is the production method according to the fifth aspect, wherein the organic solvent is a hydrocarbon solvent.

  The polymer flexible actuator of the present invention exhibits plastic deformation different from the conventional one in addition to solving the above-mentioned problems. This polymer flexible actuator is colorless and transparent, small and light and flexible, and by reversing the applied voltage, a novel gel actuator that restores the gel deformation to the initial stage can be produced.

  Hereinafter, although embodiment of this invention is described in detail, the scope of the present invention is not limited to these embodiment.

  A polymer flexible actuator is a flexible polymer actuator that deforms a dielectric polymer by applying a voltage, wherein the dielectric polymer contains a plasticizer and an ionic liquid. Is obtained.

  A plasticizer is added in an amount of 70 to 100% by weight and an ionic liquid is added in an amount of 1 to 10% by weight in an organic solvent solution of a 3% by weight dielectric polymer, followed by complete dissolution. When the obtained solution was cast on a petri dish made of polytetrafluoroethylene and dried, it was gelled with a thickness of 250 to 600 μm, 3 parts by weight of a dielectric polymer, 70 to 100 parts by weight of a plasticizer, and 1 to 1 of an ionic liquid. A polymer flexible actuator consisting of 10 parts by weight is obtained.

  FIG. 1 is a cross-sectional schematic diagram showing an example of the operating state of the flexible polymer actuator of the present invention. The flexible polymer actuator according to the embodiment of the present invention is configured such that plate-like electrodes 2a and 2b are in contact with both surfaces of a plasticized polyvinyl chloride gel 1 containing an ionic liquid, and a driving power source 3 is connected to the electrodes 2a and 2b. ing. 1A shows a state in which no voltage is applied from the driving power source 3 to the gel 1, and FIG. 1B shows a state in which the gel 1 is bent in the anode direction by applying a voltage from the driving power source 3 to the gel 1. Show the state.

  The ionic liquid used in the present invention is also called a room temperature molten salt, an ionic liquid, and the like, and refers to an organic salt composed of a cation (cation) and an anion (anion) and having a melting point at 100 ° C. or lower. In addition, it exhibits excellent thermal stability and is chemically and electrically stable.

  Examples of the cation (cation) used in the ionic liquid of the present invention include a phosphonium cation and an ammonium cation.

On the other hand, examples of the anion (anion) of the ionic liquid used in the present invention include RSO ₃ ⁻ , Cl ⁻ , and RCOO ⁻ . It is preferable that the ionic liquid used for this invention contains the salt which consists of a combination of said cation and an anion.

  Note that the dielectric polymer is polyvinyl chloride which is highly versatile.

  Plasticizers include adipic acid, sebacic acid, itaconic acid and phthalic acid esters that are compatible with polyvinyl chloride. Of these, dimethyl adipate, which is excellent in adhesiveness and response speed, is preferable.

The organic solvent is not particularly limited as long as it dissolves polyvinyl chloride, a plasticizer, and an ionic liquid, and examples thereof include ether solvents such as tetrahydrofuran. Of these, tetrahydrofuran is preferred.

  The lower the concentration of the plasticizer and the ionic liquid in the solution, the higher the initial elastic modulus of the obtained gel and the easier the processing. However, when the concentration is less than the above range, a high applied voltage is required.

  A higher concentration of plasticizer and ionic liquid in the solution is preferable because electric charges are more likely to be accumulated, so that it is driven at a lower voltage. It becomes very brittle.

  When the plasticizer concentration in the solution is 70 to 100% by weight and the ionic liquid concentration is about 5% by weight, the obtained polymer flexible actuator can be driven with a low electric field. It is particularly preferable because it has good adhesiveness, is flexible and easy to process.

Examples 1 and 2 show examples of prototype polymer flexible actuators to which the present invention is applied. An example in which the present invention is not applied is shown in Comparative Example 1. In addition, physical properties of the polymer flexible actuators of Examples and Comparative Examples were examined.
Example 1

10 parts by weight of polyvinyl chloride, 85 parts by weight of dibutyl adipate, and 5 parts by weight of trihexyl (tetradecyl) phosphonium methanesulfonic acid were dissolved in tetrahydrofuran and thoroughly stirred to completely dissolve them. The obtained solution was cast on a petri dish made of tritetrafluoroethylene for about 5 days to evaporate tetrahydrofuran, and an IL-containing plasticized PVC gel having a thickness of about 400 μm was produced as a polymer flexible actuator.
(Example 2)

10 parts by weight of polyvinyl chloride, 88 parts by weight of dibutyl adipate, and 2 parts by weight of trihexyl (tetradecyl) phosphonium methanesulfonic acid were used in the same manner as in Example 1 as a polymer flexible actuator, and the ionic liquid-containing plasticization A polyvinyl chloride gel was prepared.
(Comparative Example 1)

10 parts by weight of polyvinyl chloride and 90 parts by weight of dibutyl adipate were used in the same manner as in Example 1 to prepare an ionic liquid-free plasticized polyvinyl chloride gel as a polymer flexible actuator.
(Evaluation of voltage response of flexible polymer actuator)

  The gels obtained in Example 1 and Comparative Example 1 were cut into 10 mm length × 5 mm width. The electrode was sandwiched between aluminum electrodes, a voltage was applied in air, and the amount of tip displacement of the gel was measured using a laser displacement meter.

  FIG. 2 shows the amount of displacement when a positive voltage is applied to the obtained flexible polymer actuator.

When the behavior of Example 2 at the time of voltage application was confirmed, it was confirmed that the deformation was maintained even after the voltage application was stopped.
(Evaluation of response to reverse voltage of flexible polymer actuator)

FIG. 3 shows the behavior (displacement amount) of the polymer flexible actuator when a voltage in the positive direction is applied to the gel obtained in Example 2 under the same conditions, the voltage application direction is reversed, and the voltage is applied. .

  It is useful not only as a polymer flexible actuator of the present invention but also as an electronic device such as a capacitor, a switching device and a sensor. Moreover, it can also be set as the clothes which make it fibrous and drive an electric field.

  The polymer flexible actuator is useful as an artificial muscle.

It is a schematic cross section which shows an example of the operation state of the flexible polymer actuator to which this invention is applied. It is a graph which shows the displacement amount per elapsed time of the flexible polymer actuator of Example 1 to which this invention is applied. It is a graph which similarly shows the displacement amount per elapsed time of the flexible polymer actuator of Example 2.

Explanation of symbols

1 is an ionic liquid-containing plasticized polyvinyl chloride gel, 2a and 2b are electrodes, and 3 is a driving power source.

Claims (6)

  A flexible polymer actuator comprising a dielectric polymer, a plasticizer, and a gel comprising an ionic liquid selected from a phosphonium cation and an ammonium cation   The polymer flexible actuator according to claim 1, wherein the dielectric polymer is polyvinyl chloride.   The polymer flexible actuator according to claim 1, wherein the plasticizer is adipic acid, sebacic acid, itaconic acid or phthalic acid ester.   The flexible polymer actuator according to claim 1, comprising 1 to 50 parts by weight of the dielectric polymer, 50 to 150 parts by weight of the plasticizer, and 1 to 30 parts by weight of the ionic liquid. .   A method for producing a flexible polymer actuator including a gel, wherein a dielectric polymer and a plasticizer are dissolved in an organic solvent, an ionic liquid is mixed therein, the organic solvent is evaporated, and a gel is formed. A method for producing a polymer flexible actuator.   The method for producing a flexible polymer actuator according to claim 5, wherein the organic solvent is a hydrocarbon solvent.

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