JP2006081374A - Air drive polymer actuator element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polymer actuator capable of being driven longer than one day, even in the atmospheric pressure or in an open system without a cover. <P>SOLUTION: The polymer actuator element which contains metal electrodes and an electrolyte containing polymer electrolyte, wherein the metal electrodes are formed so as to form a pair, the metal electrodes are in contact with the electrolyte, an organic compound which has a boiling point or a decomposition temperature of 180°C or higher and is a fluid at a normal temperature and normal pressure is contained, and the electrolyte is made into a state where an ion exchange resin swells and is moistened by the organic compound. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a polymer actuator element that functions as an actuator element by applying a voltage to a pair of metal electrodes formed so as to be in contact with an electrolyte containing an ion exchange resin, thereby causing displacement or deformation.

  Conventionally, as a polymer actuator element, comprising an ion exchange resin molded product and a metal electrode formed in an insulated state on the surface of the ion exchange resin molded product, in the water-containing state of the ion exchange resin molded product, There has been provided a polymer actuator element that functions as an actuator element by applying a potential difference between metal electrodes to cause displacement and deformation of an ion exchange resin molded product (for example, Patent Document 1).

  Since this polymer actuator element is lightweight and flexible, it can be suitably used as an introduction part of a medical device such as a catheter. Furthermore, since the polymer actuator element is light in weight and simple in configuration, application as various driving devices or pressing devices is expected.

Japanese Patent No. 2961125

  The polymer actuator element can drive a large displacement or a displacement for a long time by applying a voltage to a pair of metal electrodes in an aqueous solution containing ions such as sodium ions and quaternary ammonium ions. However, when the polymer actuator element is taken out from the aqueous solution and the polymer actuator element is installed in the air, the water evaporates and ions that are charge carriers do not move. For this reason, the polymer actuator element cannot maintain the initial driving (displacement amount) for 1 hour because water evaporates when exposed to air without coating.

  The polymer actuator element can be used for a driving device in various devices in order to bend or displace. However, since the polymer actuator element cannot maintain the initial driving for 1 hour, it is substantially difficult to drive in an environment other than in an aqueous solution due to water evaporation. is there. Therefore, when the polymer actuator element is used in a driving device for various devices, there are limitations on the application.

  Further, even when the polymer actuator element is coated with a flexible polymer to prevent water from evaporating from the element, the coating layer may be cracked by driving the polymer actuator element. When generated, water evaporates from the polymer actuator element. Therefore, the polymer actuator element can maintain the initial displacement only for about 20 minutes in the air when the coating layer is not provided. Due to the occurrence of this, the initial displacement is greatly reduced within a few hours. In other words, even when the polymer actuator element is coated, it must be driven while confirming that there is no cracking of the coating resin. Therefore, even if the driving device using the polymer actuator element is coated with a flexible resin, it is not suitable for long-term use due to a monitoring burden, and the use is limited. Is done.

  An object of the present invention is to provide a polymer actuator element that can be driven for one day or more even in the environment in air under atmospheric pressure without a cover. Furthermore, an object of the present invention is to provide a polymer actuator element that can exhibit substantially the same amount of bending or displacement as the initial amount even when left in the atmosphere for 1 hour.

  As a result of intensive studies, the present inventors have found that the above problems can be solved by using the polymer actuator element of the present invention. The present invention is a polymer actuator element comprising a metal electrode and an electrolyte containing a polymer electrolyte, wherein the metal electrode is formed so as to form a pair, the metal electrode is in contact with the electrolyte, In the polymer actuator element, the electrolyte has a boiling point or decomposition temperature of 180 ° C. or higher, contains an organic compound that is liquid at normal temperature and pressure, and the electrolyte is swollen with the organic compound.

  Since the polymer actuator element of the present invention uses a specific polar solvent and has a high boiling point, it can be used to drive a bending or displacement deformation in an environment other than an aqueous solution such as air. It can be easily used for a wide variety of practical applications. In particular, the polymer actuator element is suitable for applications that require long-term driving. In the polymer actuator element, even when a specific voltage higher than 3.0 V is applied to the metal electrode in order to drive it, no electrolysis of the solvent occurs, and therefore no bubbles are generated.

  The present invention is a polymer actuator element comprising a metal electrode and an electrolyte containing a polymer electrolyte, wherein the metal electrode is formed so as to form a pair, the metal electrode is in contact with the electrolyte, In the polymer actuator element, the electrolyte has a boiling point or decomposition temperature of 180 ° C. or higher, contains an organic compound that is liquid at normal temperature and pressure, and the electrolyte is swollen with the organic compound. When the polymer actuator element includes a specific liquid organic compound, the bending amount or the displacement amount of the actuator element hardly changes. Therefore, the polymer actuator element can be driven outside the solution, that is, in the air, and is suitable for long-term driving because there is almost no evaporation of the solution.

  The organic compound that has a boiling point or decomposition temperature of 180 ° C. or higher and is in a liquid state at normal temperature and pressure is contained in the electrolyte. When the organic compound is contained in the electrolyte, the actuator element can keep a small change in the swollen state even after 1 hour without coating at room temperature and normal pressure, and the amount of bending or displacement is small. By containing the organic solvent, the electrolyte is swollen and the polymer actuator element can be easily bent or displaced. In addition, the boiling point of the present application is, as a matter of course, a boiling point measured under normal pressure.

  The organic compound is not particularly limited as long as it has a boiling point of 180 ° C. or higher or a decomposition temperature and is liquid at normal temperature and pressure. The organic compound preferably has a function as a solvent. The organic compound may be an organic compound that can serve as a salt solvent containing ions that serve as charge carriers, or an organic compound that can serve as charge carriers. The organic compound is preferably a polar organic solvent and / or an ionic liquid.

  The polar organic solvent is not particularly limited as long as it is a polar organic solvent having a boiling point of 180 ° C. or higher or a decomposition temperature, but is more preferably a polar organic solvent having a boiling point of 245 ° C. or higher. The polar solvent is more preferably diethylene glycol, glycerin, sulfolane, propylene carbonate, butyrolactone, or a mixture thereof, and particularly preferably diethylene glycol, glycerin, sulfolane, or a mixture thereof. Since the solvent component of the solution contained in the polymer actuator element is the polar solvent, bending of 50 ° or more can be performed after one day without sealing the polymer actuator element.

  Further, the conventional polymer actuator element has a surface area of the metal electrode at the interface with the ion exchange resin, for example, in order to cause bending at an angle of 270 ° or more at an applied voltage of 1.2 V, which is a relatively low voltage. Therefore, it is necessary to perform complicated pretreatment at the time of manufacturing. However, the polymer actuator element of the present invention may generate almost no gas due to water electrolysis for a certain period of time even when a specific voltage higher than 3.0 V is applied. When used under such conditions, the polymer actuator element of the present invention can be easily manufactured because the electrode can be formed more easily. In the present application, the angle (°) representing the degree of bending or displacement is obtained by measuring the angle (displacement angle) between the tangential direction of the bending or displacement convex surface at the tip of the polymer actuator element and the direction of gravity. Is.

  An ionic liquid can be used as the organic compound that is liquid at room temperature and normal pressure and has a boiling point or decomposition temperature of 180 ° C. or higher. The ionic liquid is also called a room temperature molten salt and has almost no vapor pressure at room temperature. Therefore, the polymer actuator element of the present invention in which the electrolyte contains an ion exchange resin and the ion exchange resin is swollen with an ionic liquid exhibits a bending or displacement substantially equal to the initial value even for a long period of one month. can do.

The ionic liquid is selected from the group consisting of tetraalkylammonium ions, dialkylimidazolium ions, trialkylimidazolium ions, pyrazolium ions, pyrrolium ions, pyrrolium ions, pyrrolidinium ions, and piperidinium ions. Cations,
3. A salt comprising a combination of PF ₆ ⁻ , BF ₄ ⁻ , AlCl ₄ ⁻ , ClO ₄ ⁻ and an anion selected from the group consisting of sulfonium imide anions represented by the following formula (1): The polymer actuator element described in 1.
_{(C n F (2n + 1} ) SO 2) (C m F (2m + 1) SO 2) N - (1)
(Here, n and m are arbitrary integers.)

  The tetraalkylammonium ion is not particularly limited, and trimethylpropylammonium, trimethylhexylammonium, and tetrapentylammonium can be used.

  The imidazolium cation may be a dialkyl imidazolium ion and / or a trialkyl imidazolium ion. For example, the imidazolium cation is not particularly limited, but includes 1-ethyl-3-methylimidazolium ion, 1-hexyl-3 methylimidazolium ion, 1-butyl-3-methylimidazolium ion, 1 , 3-dimethylimidazolium ion, 1-methyl-3-ethylimidazolium ion, 1,2,3-trimethylimidazolium ion, 1,2-dimethyl-3-ethylimidazolium ion, 1,2-dimethyl-3 Examples thereof include -propylimidazolium ion and 1-butyl-2,3-dimethylimidazolium ion.

  The alkylpyridinium ion is not particularly limited, but is N-butylpyridinium ion, N-methylpyridinium ion, N-ethylpyridinium ion, N-propylpyridinium ion, 1-ethyl-2-methylpyridinium ion, 1- Butyl-4-methylpyridinium, 1-butyl-2,4-dimethylpyridinium can be used.

  The pyrrolium cation is not particularly limited, but 1,1-dimethylpyrrolium ion, 1-ethyl-1-methylpyrrolium ion, 1-methyl-1-propylpyrrolium ion, 1-butyl-1-methyl Pyrrolium ions can be used.

  The pyrazolium cation is not particularly limited, but 1,2-dimethylpyrazolium ion, 1-ethyl-2-methylpyrazolium ion, 1-propyl-2-methylpyrazolium ion, 1-butyl A 2-methylpyrazolium ion can be used.

The pyrrolium cation is not particularly limited, but 1,2-dimethylpyrrolium ion, 1-ethyl-2-methylpyrrolium ion, 1-propyl-2-methylpyrrolium ion, 1-butyl- 2-Methylpyrrolinium ion can be used.

The pyrrolidinium cation is not particularly limited, but 1,1-dimethylpyrrolidinium ion, 1-ethyl-1-methylpyrrolidinium ion, 1-methyl-1-propylpyrrolidinium ion, 1-butyl A -1-methylpyrrolidinium ion can be used.

The piperidinium cation is not particularly limited, but 1,1-dimethylpiperidinium ion, 1-ethyl-1-methylpiperidinium ion, 1-methyl-1-propylpiperidinium ion, 1-butyl A -1-methyl piperidinium ion can be used.

The ionic liquid is not particularly limited in the combination of the anion and the cation. For example, 1-methyl-3-ethylimidazolium trifluoromethanesulfimide (EMITFSI), 1-methyl-3-imidazo Rium tetrafluoroborate (EMIBF ₄ ), 1-methyl-3-imidazolium hexafluorophosphoric acid (EMIPF ₆ ), trimethylpropylammonium trifluoromethanesulfonimide, 1-hexyl-3-methylimidazolium tetrafluoroborate, 1-hexyl -3-Methylimidazolium hexafluorophosphoric acid, 1-hexyl-3-methylimidazolium trifluoromethanesulfimide can be used.

  In the polymer actuator element of the present invention, when the electrolyte contains the ion exchange resin and the ionic liquid, the ion exchange resin can be a gel electrolyte swollen with the ionic liquid. When the electrolyte contains an ion exchange resin and an ionic liquid, the polymer actuator element can be driven even when left for one month at atmospheric pressure. Furthermore, since the gel electrolyte containing an ion exchange resin and an ionic liquid is flexible and can hold a high concentration of electrolyte, it is suitable as an electrolyte for actuator elements and capacitors.

  The manufacturing method of the electrolyte containing the ion exchange resin and the ionic liquid is not particularly limited, but the ionic liquid is 1 to 90% by weight in a known polar solvent having a boiling point of 100 ° C. or less. It can be easily obtained by immersing the ion exchange resin in a mixed solution containing a proportion and leaving it at room temperature until there is no change in size or weight, or leaving it for more than an hour.

  The polymer actuator element of the present invention includes a metal electrode and an ion exchange resin electrolyte, and is formed so that the metal electrode can form a pair. The metal electrode is in contact with the electrolyte and is a polymer actuator element. And having a structure including a plurality of the metal electrodes. The actuator element may include one electrode layer on each side of the ion exchange resin layer, or may include a plurality of electrode layers on both sides or one side. As a specific structure of the actuator element, for example, an actuator element in which a pair of electrode layers form an electrode pair with an ion exchange resin layer sandwiched between them can be used, and an outer surface of a tubular ion exchange resin and / or A plurality of metal electrodes may be provided on the inner surface.

  A polymer actuator element in which the electrode layer forms an electrode pair with an ion exchange resin interposed therebetween can be obtained by a known method. For example, by performing electroless plating on an ion exchange resin tangible material having a membrane shape, a plate shape, or a tubular shape, a metal layer is formed on the inner surface of the ion exchange resin tangible surface or the ion exchange resin tangible surface, By using the metal layer metal as an electrode layer, a metal-ion exchange resin assembly that is the polymer actuator element can also be obtained.

  As the electroless plating, for example, the following electroless plating method can be suitably used. After performing the roughening treatment, an adsorption step is performed in which the ion exchange resin is immersed in water and swollen to adsorb a metal complex such as a platinum complex or a gold complex to the ion exchange resin. Next, a reduction step of reducing the adsorbed metal complex with a reducing agent to deposit a metal is performed, and a cleaning step of cleaning and removing the reducing agent is optionally performed after the reduction step.

  In this electroless plating, the adsorption process, the reduction process, and the cleaning process can be repeated as one cycle in order to make the metal layer as an electrode thick enough for energization, bending, or displacement. In the actuator element thus obtained, an electrode layer grows in the inner direction of the ion exchange resin to form an electrode, and the cross section of the electrode layer has a fractal structure at the interface between the ion exchange resin and the electrode layer. Since it forms, it can have a big electric double layer in the interface of the said electrode layer and the said ion exchange resin layer. Further, since the electrode layer forms a fractal structure in the inner direction of the ion exchange resin layer, the anchor effect is exerted, so that the ion exchange resin assembly is durable even when it is repeatedly bent.

  The ion exchange resin contained in the electrolyte of the polymer actuator element of the present invention is not particularly limited. The ion exchange resin is not particularly limited, and a known ion exchange resin can be used. When a cation exchange resin is used, a sulfonic acid group or a carboxyl group is added to polyethylene, polystyrene, fluororesin, or the like. What introduced hydrophilic functional groups, such as these, can be used. Examples of such resins include perfluorosulfonic acid resin (trade name “Nafion”, manufactured by DuPont), perfluorocarboxylic acid resin (trade name “Flemion”, manufactured by Asahi Glass), ACIPLEX (manufactured by Asahi Kasei Kogyo Co., Ltd.), NEOSEPTA (manufactured by Tokuyama Corporation) can be used.

  The metal complex solution used in the electroless plating adsorption step is not particularly limited as long as the metal layer formed by reduction contains a metal complex that can function as an electrode layer. . The metal complex is preferably a metal complex such as a gold complex, a platinum complex, a palladium complex, a rhodium complex, or a ruthenium complex because a metal having a small ionization tendency is electrochemically stable. Since it is used as an electrode, a metal complex composed of a noble metal having good electrical conductivity and high electrochemical stability is preferable, and a gold complex composed of gold that is relatively difficult to undergo electrolysis is preferable. In the metal salt solution, the solvent is not particularly limited. However, since the metal salt is easy to dissolve and easy to handle, the solvent is preferably based on water. A metal salt aqueous solution is preferred. Therefore, the metal complex solution is preferably a metal complex aqueous solution, particularly preferably a gold complex aqueous solution or a platinum complex aqueous solution, and more preferably a gold complex aqueous solution.

  As the reducing agent used in the reduction process of electroless plating, depending on the type of metal complex used in the metal complex solution adsorbed on the ion exchange resin, the type can be appropriately selected and used, for example, sulfurous acid. Sodium, hydrazine, sodium borohydride, phosphorous acid, sodium hypophosphite and the like can be used.

The reducing agent can be appropriately selected depending on the metal species to be deposited. When the metal deposited by reduction is nickel or cobalt, sodium phosphinate, dimethylaminoborane, hydrazine, or potassium tetrahydroborate can be used as the reducing agent. When the metal deposited by reduction is palladium, sodium phosphinate, sodium phosphonate, or potassium tetrahydroborate can be used as the reducing agent. When the metal deposited by reduction is copper, formalin, sodium phosphonate, or potassium tetrahydroborate can be used as the reducing agent. When the metal deposited by reduction is silver or gold, dimethylaminoborane and potassium tetrahydroborate can be used as the reducing agent. When the metal deposited by reduction is platinum, hydrazine and sodium tetrahydroborate can be used as the reducing agent. When the metal deposited by reduction is tin, titanium trichloride can be used as the reducing agent. Further, the reducing agent is not limited to the above type, but is used with a catalyst such as platinum black, hydrogen, non-metallic acid or ion such as HgS, HI or I ⁻ , Na (H ₂ PO ₂ ) or Na lower oxyacid salts, such as ₂ S ₂ O _3, lower oxides such as CO or SO2, Li, Na, Cu, Mg, Zn, Fe, Fe (II), Sn (II), Ti (III), Cr ( II) metals having a high ionization tendency or their amalgams and low-valent metal salts, hydrides such as AlH [(CH3) 2CHCH2] 2 and lithium aluminum hydride, diimides, formic acid, aldehydes, saccharides and L-ascorbic acid Etc. can be used as appropriate.

  The reducing agent can be appropriately selected according to the metal species to be reduced. However, the growth rate of plating, the particle size of the deposited metal, the contact area between the metal electrode of the fractal structure and the ion exchange resin, the electrode structure, and In order to change the flexibility of the resin after plating, the optimum type of reducing agent can be selected and used. Moreover, in order to make the reducing bath in the reduction step have a desired pH, the type of the reducing agent can be appropriately selected.

In addition, when reducing a metal complex, you may add an acid or an alkali as needed. The concentration of the reducing agent solution is not particularly limited as long as it contains a sufficient amount of reducing agent to obtain the amount of metal to be deposited by reduction of the metal complex. It is also possible to use a concentration equivalent to the metal salt solution used when forming the electrode by plating. Further, the reducing agent solution can contain a good solvent for the ion exchange resin.

  The polymer actuator element of the present invention includes a solvent and a salt inside an electrolyte in contact with a metal electrode formed so that a pair can be formed. The polymer actuator element is preferably flexible so that the polymer actuator element can be bent or displaced. In order to obtain the flexibility, in the polymer actuator element, the ion exchange resin is swollen with a liquid organic compound at normal temperature and pressure. The degree of swelling is not particularly limited, but the degree of swelling of the polymer actuator element, that is, in the swollen state of the polymer actuator element with respect to the thickness of the polymer electrolyte in a dry state. The thickness increase rate is preferably 3 to 200%, more preferably 5 to 60%. When the degree of swelling is less than 3%, the displacement bending performance is inferior, and when the degree of swelling is greater than 200%, the displacement bending performance is also inferior and the tensile strength is greatly reduced. . In addition, although the said organic compound is contained in electrolyte, when an electrode layer is a porous electrode, a part of said solvent may be contained in a pre-metal electrode layer with a salt.

  Further, the polymer actuator element of the present invention has a large bending or displacement because the electrolyte has a higher degree of swelling when the organic compound is a polar organic solvent than when an ionic liquid is used. Can be suitably used for applications that require. On the other hand, when an ionic liquid is used as the organic compound, the degree of swelling is smaller than when a polar organic solvent is used, but it swells even if left as an open system at room temperature and normal pressure for a period of about one month. Therefore, the polymer actuator element can be driven without a large change in the amount of bending or displacement during a period of about one month without the need for providing a cover. In order to obtain the electrolyte, it can be obtained by immersing the ion exchange resin layer in a liquid of the organic compound. For example, when the polymer actuator element is an element in which a metal electrode is formed by performing electroless plating on an ion exchange resin, the polymer actuator element is immersed in a liquid in the organic compound for about one night. By soaking, an element in which the ion exchange resin is swollen by the organic compound can be obtained.

  The electrolyte of the polymer actuator element of the present invention may be in a state where the ion exchange resin is swollen by the ionic liquid. When the ion exchange resin is swollen by the ionic liquid and the ion exchange resin does not swell even when the ion exchange resin is immersed in the ionic liquid, the ion exchange resin is mixed with the solvent for swelling and the ionic liquid. The electrolyte in which the ion exchange resin is swollen with the ionic liquid can be easily obtained by evaporating the swelling solvent after swelling the exchange resin. Further, a high boiling polar organic solvent can be used as the swelling solvent and left in the device. The swelling solvent is a solvent that can swell the ion exchange resin and dissolve the ionic liquid. The above-mentioned swelling does not include infinite swelling in the present application.

In the polymer actuator element of the present invention, the salt contained in the electrolyte in contact with the metal electrode formed so that a pair can be formed can be dissolved in the liquid organic compound at the normal temperature and pressure. Although not particularly limited, when the polymer electrolyte forms a counter ion with a cation, a salt of a monovalent to trivalent cation can be used, and a monovalent salt such as Na +, K +, or Li + can be used. It is preferable to use a cation because it can be bent or displaced greatly, and it is further preferable to use an alkylammonium ion having a large ionic radius because it can be bent or displaced more greatly. Examples of the alkyl ammonium ion include CH ₃ N ⁺ H ₃ , C ₂ H ₅ N ⁺ H ₃ , (CH ₃ ) ₂ N ⁺ H ₂ , (C ₂ H ₅ ) ₂ N ⁺ H ₂ , and (CH ₃ ) _3. N ⁺ H, (C ₂ H ₅ ) ₃ N ⁺ H, (CH ₃ ) ₄ N ⁺ , (C ₂ H ₅ ) ₄ N ⁺ , (C ₃ H ₇ ) ₄ N ⁺ , (C ₄ H ₉ ) ₄ N ⁺ , H ₃ N ⁺ (CH ₂ ) ₄ N ⁺ H ₃ , H ₂ C═CHCH ₂ N ⁺ HCH ₃ , H ₃ N ⁺ (CH ₂ ) ₄ N ⁺ H ₂ (CH ₂ ) ₄ N ⁺ H ₃ , HC≡CCH ₂ N ⁺ H ₂ , CH ₃ CH (OH) CH ₂ N ⁺ H ₃ , H ₃ N ⁺ (CH ₂ ) ₅ OH, H ₃ N ⁺ CH (CH ₂ OH) ₂ , (HOCH ₂ ) ₂ C (CH ₂ N ⁺ H ₃ ) ₂ , C ₂ H ₅ OCH ₂ CH ₂ N ⁺ H ₃ or an ammonium ion having an aliphatic hydrocarbon as a substituent, or an alicyclic in addition to a hydrocarbon as a functional group Ammonium ions having cyclic hydrocarbons can also be used. At this time, the concentration of the salt only needs to be contained as a concentration equal to or higher than the functional group of the ion exchange resin, and is 0.01 to 10 mol / l in order to obtain sufficient bending or displacement. Is preferable, and it is more preferable that it is 0.1-1.0 mol / l. In addition, when using an ionic liquid as a liquid organic compound at normal temperature and normal pressure, it is not necessary to use said salt.

  Since the polymer actuator element of the present invention contains the above-mentioned polar solvent, it can be driven for one day or more without being coated with a resin, but may be further coated with a flexible resin. Although it does not specifically limit as said resin, A polyurethane resin and / or a silicon resin can be used. The polyurethane resin is not particularly limited, but it is particularly preferable to use a flexible thermoplastic polyurethane because of its high flexibility and good adhesion. As a flexible thermoplastic polyurethane, a trade name “Asaflex 825” (flexibility 200%, manufactured by Asahi Kasei Co., Ltd.), a trade name “Peresen 2363-80A” (flexibility 550%), “Peresen 2363-80AE” (flexibility) 650%), “Pelecene 2363-90A” (flexibility: 500%), “Pelecene 2363-90AE” (flexibility: 550%), (manufactured by Dow Chemical Co., Ltd.). Further, the silicone resin is not particularly limited, but a resin having a flexibility of 50% or more is particularly preferable because of its high flexibility and good adhesion. As the silicone resin, for example, “SilaSeal 3FW”, “SilaSeal DC738RTV”, “DC3145”, and “DC3140” (above, manufactured by Dow Corning) can be used. In addition, in this application, a softness | flexibility means the tensile breaking elongation (Ultimate Elongation%) based on ASTMD412.

(Driving method)
The present invention is also a method for driving a polymer actuator element. The polymer actuator element is a polymer actuator element provided with a pair of metal electrodes formed so as to face each other with an ion exchange resin interposed therebetween, and is a polymer actuator element provided with a pair of metal electrodes, Since this is a polymer actuator element containing a polar solvent having a boiling point of 180 ° C. or higher in the ion exchange resin, a voltage higher than 3.0 V was applied in order to cause bending or displacement of 160 ° C. or higher. However, since the solvent is not easily evaporated without generating bubbles, it can be driven for one day or more without being covered with resin.

  As described above, the driving method uses a polar solvent having a boiling point of 180 ° C. or higher as a solvent that swells the polymer actuator element and dissolves ions as charge carriers, as described above. It is not particularly limited. In particular, the polar solvent is preferably diethylene glycol and / or glycerin because it can be bent at 160 ° or more.

  Hereinafter, although the Example and comparative example of this invention are described, this invention is not limited to these.

Example 1
An ion exchange resin membrane having a thickness of 0.2 mm when dried (fluororesin-based ion exchange resin: perfluorocarboxylic acid resin, trade name “Flemion”, manufactured by Asahi Glass Co., Ltd., ion exchange capacity 1.4 meq / g) is shown below ( The processes of 1) to (3) were repeated 6 cycles to obtain an ion exchange resin membrane provided with a pair of metal electrodes formed with the ion exchange resin sandwiched therebetween. (1) Adsorption process: It was immersed in a dichlorophenanthroline gold chloride aqueous solution for 12 hours to adsorb the dichlorophenanthroline gold complex in the molded article. (2) Reduction step: The adsorbed dichlorophenanthroline gold complex was reduced in an aqueous solution containing sodium sulfite to form a gold electrode on the membrane polymer electrolyte. At this time, the temperature of the aqueous solution was set to 60 to 80 ° C., and the dichlorophenanthrine gold complex was reduced for 6 hours while gradually adding sodium sulfite. Next, (3) washing step: The membrane polymer electrolyte having a gold electrode formed on the surface was taken out and washed with water at 70 ° C. for 1 hour. The ion exchange resin film on which a pair of metal electrodes was formed by electroless plating was cut into a length of 22 mm and a width of 1.5 mm. Next, the ion exchange resin membrane is dipped in an aqueous solution of 0.5 mol / l tetraethylammonium chloride and dried, and then 0.5 mol / l of tetraethyleneammonium chloride is added so that the degree of swelling is about 15%. The polymer actuator element of Example 1 was obtained by being immersed in a diethylene glycol solution for 24 hours.

(Example 2)
Other than using a 0.5 mol / l propylene carbonate solution of tetraethyleneammonium chloride instead of 0.5 mol / l tetraethyleneammonium diethylene glycol solution as a solvent for immersing the cut ion exchange resin membrane. Obtained the polymer actuator element of Example 2 by the same method as Example 1.

(Example 3)
The solvent for immersing the cut ion exchange resin membrane was changed to 0.5 mol / l tetraethyleneammonium chloride diethylene glycol solution, except that 0.5 mol / l tetraethyleneammonium chloride glycerin solution was used. The polymer actuator element of Example 3 was obtained in the same manner as in Example 1.

Example 4
The solvent for immersing the cut ion exchange resin membrane was changed to 0.5 mol / l tetraethyleneammonium chloride diethylene glycol solution, except that a 0.5 mol / l tetraethyleneammonium chloride sulfolane solution was used. The polymer actuator element of Example 4 was obtained in the same manner as in Example 1.

(Example 5)
The solvent for immersing the cut ion exchange resin membrane was changed to a 0.5 mol / l tetraethyleneammonium chloride diethylene glycol solution, but a 0.5 mol / l tetraethyleneammonium chloride butyrolactone solution was used. The polymer actuator element of Example 3 was obtained in the same manner as in Example 1.

(Example 6)
An ion exchange resin membrane having a thickness of 0.2 mm when dried (fluororesin-based ion exchange resin: perfluorocarboxylic acid resin, trade name “Flemion”, manufactured by Asahi Glass Co., Ltd., ion exchange capacity 1.4 meq / g) is shown below ( The processes of 1) to (3) were repeated 6 cycles to obtain an ion exchange resin membrane provided with a pair of metal electrodes formed with the ion exchange resin sandwiched therebetween. (1) Adsorption process: It was immersed in a dichlorophenanthroline gold chloride aqueous solution for 12 hours to adsorb the dichlorophenanthroline gold complex in the molded article. (2) Reduction step: The adsorbed dichlorophenanthroline gold complex was reduced in an aqueous solution containing sodium sulfite to form a gold electrode on the membrane polymer electrolyte. At this time, the temperature of the aqueous solution was set to 60 to 80 ° C., and the dichlorophenanthrine gold complex was reduced for 6 hours while gradually adding sodium sulfite. Next, (3) washing step: The membrane polymer electrolyte having a gold electrode formed on the surface was taken out and washed with water at 70 ° C. for 1 hour. The ion exchange resin film on which a pair of metal electrodes was formed by electroless plating was cut into a length of 22 mm and a width of 1.5 mm. Next, the ion exchange resin membrane was dipped in an aqueous solution of 0.5 mol / l tetraethylammonium chloride and dried, and then diluted with an aqueous solution of 0.2 mol / l ethylmethylimidazolium trifluoromethanesulfonimide salt (EMITFSI). The polymer actuator element of Example 6 was obtained by immersing at room temperature overnight and air drying at room temperature for 2 hours or more to evaporate water.

(Example 7)
Implementation was performed except that an aqueous solution of 0.2 mol / l of ethylmethylimidazolium hexafluorophosphate (EMIPF ₆ ) was used instead of the aqueous solution of 0.2 mol / l of ethylmethylimidazolium trifluoromethanesulfonimide salt. In the same manner as in Example 6, the polymer actuator element of Example 7 was obtained.

(Example 8)
Implementation was performed except that an aqueous solution of 0.2 mol / l of ethylmethylimidazolium tetrafluoroborate (EMIBF ₄ ) was used instead of the aqueous solution of 0.2 mol / l of ethylmethylimidazolium trifluoromethanesulfonimideimide salt. A polymer actuator element of Example 8 was obtained in the same manner as Example 6.

Example 9
Example 6 was used except that instead of the 0.2 mol / l ethylmethylimidazolium trifluoromethanesulfonimide salt aqueous solution, an aqueous solution of 0.2 mol / l trimethylpropylammonium trifluoromethanesulfonimide salt (TMPATFSI) was used. Similarly, a polymer actuator element of Example 9 was obtained.

(Example 10)
Other than using 0.2 mol / l of an aqueous solution of 1-butyl 3-methylimidazolium tetrafluoroborate (BMIBF ₄ ) instead of 0.2 mol / l of ethylmethylimidazolium trifluoromethanesulfonimide salt aqueous solution Obtained a polymer actuator element of Example 10 in the same manner as in Example 6.

(Example 11)
Other than using an aqueous solution of 0.2 mol / l 1-hexyl 3-methylimidazolium hexaolophosphate (HMIPF ₆ ) instead of the 0.2 mol / l ethylmethylimidazolium trifluoromethanesulfonimide salt aqueous solution Obtained a polymer actuator element of Example 11 in the same manner as in Example 6.

(Comparative example)
Except for using a 0.5 mol / l aqueous solution of tetraethyleneammonium chloride in place of the solvent for immersing the cut ion exchange resin membrane in place of a 0.5 mol / l tetraethyleneammonium chloride diethylene glycol solution, A polymer actuator element of a comparative example was obtained in the same manner as in Example 1.

[Evaluation]
About the polymer actuator element of Examples 1-11 and a comparative example, the displacement angle in the air and the element property in 3.0V voltage application were evaluated with the following method. The results are shown in Table 1.

(Displacement angle in air)
For each of the polymer actuator elements of Examples 1 to 11 and the comparative example, the thickness of the polymer actuator element at the platinum terminal is such that each pair of metal electrodes can be energized at a position 2 mm inside from one end. The film surface was gripped so that the film surface was parallel to the gravity direction. 1. Using a potentiostat (DC mode, trade name “Potentio Galvanostat HA-501”, manufactured by Hokuto Denko Co., Ltd.) so that one of the pair of metal electrodes is a positive electrode and the other is a negative electrode. A voltage of 5 V was applied, and a voltage was applied so that an opposite voltage was applied to each metal electrode at a period of 0.1 Hz, and a displacement motion reciprocating left and right was performed. The angle formed by the tangential direction of the displacement convex surface at the tip of the polymer actuator element and the gravity direction in the bent or displaced state at the third reciprocation of this reciprocating displacement movement is measured in the right displacement and the left displacement, and averaged. The displacement angle was determined. This measurement was carried out for each polymer actuator element at 1 minute, 1 hour, and 24 hours after being held by the platinum terminal.

(result)
In the polymer actuator element of Example 1, since diethylene glycol, which is a polar solvent having a boiling point of 245 ° C., is contained in the element as a solvent, even after 24 hours, that is, after one day, 100 ° or more at an applied voltage of 1.2 V The displacement angle is shown. On the other hand, since the polymer actuator element of the comparative example contained water as a polar solvent having a boiling point of 100 ° C. as a solvent, no displacement occurred after 24 hours.

  Since the polymer actuator elements of Examples 2 to 5 were included in the element with polar solvents having boiling points of 204 to 290 ° C., displacements of 50 ° or more at an applied voltage of 1.2 V even after 24 hours. The corner was shown. In particular, in Example 4, the displacement angle after 24 hours was 80% of the displacement angle after 1 minute, and the change in displacement was small and good.

  In the polymer actuator elements of Examples 6 to 11, the degree of swelling was 14.0 to 22.1% and the displacement angle was not large, but there was almost no decrease in displacement. In addition, the polymer actuator elements of Examples 6 to 11 were good with little decrease in displacement even when left for one month in an open system at room temperature without being covered. A polymer actuator element using an ionic liquid is not very suitable for an application that requires a large amount of displacement, but is suitably used for an application that requires a small amount of displacement, such as a switching device.

  As shown by the polymer actuator elements of Examples 1 to 11, the performance over time is sufficient with the ability to drive for one day in the room temperature release system, and there is almost no decrease in the amount of displacement after one hour. For applications where the amount is required, a polar organic solvent can be suitably used as the organic compound which is liquid at normal pressure and room temperature with a boiling point of 180 ° C. or higher. On the other hand, although a large amount of displacement is not required, the boiling point is 180 ° C. or higher for applications in which the amount of displacement hardly changes even if left in a room temperature release system for one day and the displacement can be made even after one month. As the organic compound that is liquid at normal pressure and room temperature, an ionic liquid can be suitably used. The polar organic solvent and the ionic liquid may be mixed at an arbitrary ratio in order to control the displacement amount and the change of the displacement amount with time.

  Even when the polymer actuator elements of Examples 1 to 11 are covered and scratched, they become a release system due to scratches compared to the polymer actuator element using an aqueous solvent as in Comparative Example 1. Even in such a state, it can be driven for a long time. Further, when the polymer actuator elements of Examples 1 to 11 are not covered, the covering layer does not hinder the bending, and thus the bending inherent in the element can be performed.

  The polymer actuator element of the present invention can be used as an actuator element that causes displacement or bending displacement. Further, by combining the laminate with a device that converts a bending motion into a linear motion, an actuator that generates a displacement linearly can also be used. An actuator that generates a linear displacement or a bending displacement can be used as a driving unit that generates a linear driving force or a driving unit that generates a driving force for moving a track-type orbit made of an arc portion. . Further, the actuator can be used as a pressing portion that performs a linear operation.

  That is, the actuator is an OA device, an antenna, a device for placing a person such as a bed or a chair, a medical device, an engine, an optical device, a fixture, a side trimmer, a vehicle, a lifting device, a food processing device, a cleaning device, a measuring device, Inspection equipment, control equipment, machine tools, processing machines, electronic equipment, electron microscopes, electric razors, electric toothbrushes, manipulators, masts, amusement equipment, amusement equipment, riding simulation equipment, vehicle occupant restraining devices, and aircraft accessories In the device, as a driving unit that generates a linear driving force, a driving unit that generates a driving force for moving a track-type track composed of an arc portion, or a pressing unit that performs a linear operation or a curved operation It can be used suitably. The actuator is, for example, a track-type track formed of a drive unit or a circular arc unit that generates a linear drive force in valves, brakes, and lock devices used in all machines including the above-described devices such as OA devices and measurement devices. It can be used as a driving unit that generates a driving force for moving the sway, or a pressing unit that performs a linear operation. In addition to the above-mentioned devices, devices, instruments, etc., in general mechanical devices, a positioning device drive unit, a posture control device drive unit, a lifting device drive unit, a transport device drive unit, and a movement device drive unit It can be suitably used as a drive unit for an adjustment device such as an amount and a direction, a drive unit for an adjustment device such as a shaft, a drive unit for a guidance device, and a pressing unit for a pressing device. In addition, since the actuator can perform a rotational motion, a drive unit of a switching device, a drive unit of a reversing device such as a conveyed product, a drive unit of a winding device such as a wire, a drive unit of a traction device, It can also be used as a drive unit for a swiveling device in the left-right direction such as swinging.

Claims (7)

A polymer actuator element comprising a metal electrode and an electrolyte comprising a polymer electrolyte,
The metal electrodes are formed to form a pair;
The metal electrode is in contact with the electrolyte;
A polymer actuator element, wherein the electrolyte has a boiling point or decomposition temperature of 180 ° C. or higher, contains an organic compound that is liquid at normal temperature and pressure, and the electrolyte is in a state in which an ion exchange resin is swollen by the organic compound. The polymer actuator element according to claim 1, wherein the organic compound is a polar organic solvent and / or an ionic liquid. The ionic liquid is
A cation selected from at least one selected from the group consisting of tetraalkylammonium ions, dialkylimidazolium ions, trialkylimidazolium ions, pyrazolium ions, pyrrolium ions, pyrrolium ions, pyrrolidinium ions, and piperidinium ions;
3. A salt comprising a combination of PF ₆ ⁻ , BF ₄ ⁻ , AlCl ₄ ⁻ , ClO ₄ ⁻ and an anion selected from the group consisting of sulfonium imide anions represented by the following formula (1): The polymer actuator element described in 1.
_{(C n F (2n + 1} ) SO 2) (C m F (2m + 1) SO 2) N - (1)
(Here, n and m are arbitrary integers.) The polymer actuator element according to claim 2 or 3, wherein the electrolyte is a polymer gel electrolyte containing an ion exchange resin and an ionic liquid. The polymer actuator element according to claim 1, wherein the polymer actuator element is in a state swollen by the organic compound and has a swelling degree of 3 to 200%. The polymer actuator element according to claim 1, wherein the polymer actuator element is coated with a flexible resin. A polymer gel electrolyte comprising an ion exchange resin and an ionic liquid.