JP2010093954A - Polymer transducer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polymer transducer that stably exhibits excellent performance even when no water exists, and to provide a polymer actuator that can be driven at a low voltage or a displacement sensor exhibiting excellent responsiveness. <P>SOLUTION: The polymer transducer comprises a polymer solid electrolyte including ionic liquid and a polymer component, and electrodes in contact with each other with the polymer solid electrolyte therebetween and insulated from each other. At least one of the electrodes includes a porous active material whose specific surface area As is at least 100 m<SP>2</SP>/g and in which a ratio Ao/As between the specific surface area As and an external surface area Ao is at least 0.1. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a polymer transducer, and more particularly to a polymer actuator whose performance is improved by using an electrode containing an active material that satisfies specific requirements, or a polymer transducer that can be used as a displacement sensor.

  In recent years, in the fields of medical equipment and micromachines, there is an increasing need for transducers such as small and lightweight actuators and sensors. In addition, in the fields of industrial and personal robots, there is an increasing need for transducers that are light and flexible.

  From this point of view, polymer actuators are attracting attention as actuators that are lightweight and have a flexible drive section. Various types of polymer actuators have been proposed so far. For example, it comprises a polymer actuator (see Patent Document 1) that utilizes a change in the shape of a hydrous polymer gel caused by a stimulus such as temperature change, pH change, and electric field application, an ion-exchange resin film, and electrodes joined to both surfaces thereof. There has been proposed a polymer actuator (see Patent Document 2) that causes a curve and deformation by applying a potential difference between electrodes on both surfaces in a water-containing state of an exchange resin film. Especially in the latter, bending and deformation instantly appear in response to the polymer actuator after application of the electrode and show very excellent responsiveness, but on the other hand, its application range is limited because it operates only in a water-containing state. There is a problem of being done.

  As a means for overcoming these problems, a polymer actuator comprising a soft polymer dielectric and a flexible electrode has been reported (see Patent Document 3). This type of polymer actuator does not require water for operation, and the operation of the actuator is not a mass transfer phenomenon such as ions, but is due to an electron transfer phenomenon which is a faster process, so it is very responsive. It is excellent. However, on the other hand, a very high voltage of about several thousand volts is required for the operation, and there is a problem that the application range is limited from the viewpoint of safety.

  In order to overcome this problem, a polymer actuator in which an electrode made of an ionic liquid, a fluorine-based polymer, and a single-walled carbon nanotube is bonded to both surfaces of a non-aqueous polymer solid electrolyte made of an ionic liquid and a fluorine-based polymer (non- Patent Document 1) and a polymer actuator (Patent Document 4) in which electrodes containing activated carbon are bonded to both surfaces of a nonaqueous polymer solid electrolyte made of an ionic liquid and a block copolymer have been reported. These polymer actuators are characterized by being driven at a voltage as low as several volts even in the absence of water, but they are not satisfactory in terms of the force and operating speed that the actuator can generate.

  The function of the polymer transducer has not only the function as the actuator described above but also the function as a sensor. Conventionally, piezoelectric elements using piezoelectric ceramics or the like have been widely used as sensors that convert mechanical energy into electrical energy. Piezoelectric ceramics represented by barium titanate, lead zirconate titanate (PZT), and the like convert mechanical energy into electrical energy by a piezoelectric effect that generates charges when the ceramic is subjected to stress.

  However, sensors using these piezoelectric ceramics often cannot be used in applications that require low weight because they use a high-density inorganic material. In addition, since the impact resistance is inferior, when an external impact is applied, the piezoelectric ceramic is destroyed and the sensor function is likely to be deteriorated. In addition, since it is inferior in flexibility, it is difficult to use it in applications where it is required to install it on a complex-shaped structure having a spherical surface or unevenness, and it is difficult to detect large deformations and small stresses. It was.

JP-A 63-309252 Japanese Patent Publication No. 7-4075 Special table 2003-505865 gazette PCT International Publication No. WO2008 / 044546 Future Materials, Vol. 5, 10, p. 14, 2005 “Studieson Pore Systems in Catalysts V. The t Method”, B. C. Lippens and J. H. de Boer, J. Catalysis, 4, 319 (1965).

  An object of the present invention is to provide a polymer transducer that exhibits stable and excellent performance even in the absence of water, and thus provides a polymer actuator that can be driven at a low voltage.

  As a result of intensive studies based on the object of the present invention, the present inventors have found that a polymer solid electrolyte containing an ionic liquid and a polymer component, and electrodes that are in contact with each other with the polymer solid electrolyte sandwiched therebetween and insulated from each other A polymer transducer using an active material in which at least one of the electrodes satisfies a specific requirement is a force generated by an actuator, a displacement amount, an operating speed, an output intensity as a sensor, and a signal / noise. It has been found that it is excellent in performance such as a ratio (S / N ratio) and can be suitably used for various applications.

  Further, the present inventors have found that when the polymer transducer of the present invention is used as an actuator, it operates efficiently with a small amount of charge compared to an actuator outside the scope of the present invention. The polymer actuator is essentially the same structure as an electric double layer capacitor, and in order to store more charge, and to take out the stored charge to the outside, energy loss due to internal resistance is inevitably large, That is, it becomes difficult to use energy effectively. However, since the polymer actuator of the present invention can operate efficiently even with a small amount of charge, it can reduce the above-mentioned energy loss and can be used as an actuator with excellent energy efficiency.

The polymer transducer according to claim 1 of the present invention made based on these findings is in contact with a solid polymer electrolyte containing an ionic liquid and a polymer component, with the polymer solid electrolyte sandwiched between them. A polymer transducer comprising at least one electrode insulated from each other, wherein at least one of the electrodes includes a porous active material, the specific surface area As of the active material is at least 100 m ² / g, and the specific surface area As and the external surface area An active material having an Ao ratio Ao / As of at least 0.1 is included.

  Similarly, the polymer transducer described in claim 2 is the polymer transducer described in claim 1, wherein the specific surface area As is a value obtained by a thickness plot method (t method).

  A polymer transducer described in claim 3 is the polymer transducer described in claim 1 or 2, wherein the main constituent element of the active material is carbon.

  Similarly, a polymer actuator according to a fourth aspect is characterized in that the polymer transducer according to the first, second, or third aspect is used as a drive unit.

  A polymer actuator according to a fifth aspect is the polymer actuator according to the fourth aspect, wherein the electrode and the trigger member are integrated.

  The polymer transducer of the present invention is excellent in performance such as generated force, displacement, operating speed, and sensitivity, and can be used for various applications. When this polymer transducer is used as an actuator, it has excellent characteristics such as generated force, displacement, and operating speed, and has the flexibility and light weight characteristic of polymer actuators. Can be suitably used. In addition, when this polymer transducer is used as a displacement sensor, it is excellent in fluctuation, deformation and pressure detection performance, detection sensitivity, and S / N ratio of detection output, as well as flexibility and light weight.

Preferred form for carrying out the invention

  Hereinafter, preferred embodiments of the present invention will be described in detail.

The polymer transducer of the present invention comprises a polymer solid electrolyte containing an ionic liquid and a polymer component, and electrodes which are in contact with each other with the polymer solid electrolyte interposed therebetween and insulated from each other. At least one of the electrodes contains an active material that satisfies the following requirements 1 and 2. Requirement 1 is that the specific surface area As determined by the thickness plot method is 100 m ² / g or more. Requirement 2 is that the ratio Ao / As of the specific surface area As and the external surface area Ao is at least 0.1.

  The specific surface area is literally the surface area per unit mass of the substance. For example, when there are holes, cracks, etc. on the outer surface of a sphere, square, etc. It can be said that it is the total surface area including the surface area. When there are no pores (non-porous), only the area of the outer shape such as a sphere or a rectangle becomes the specific surface area. On the other hand, the external surface area is the area outside the shape of a sphere, square, etc., regardless of the presence or absence of holes, etc., and is the same regardless of whether it is porous or non-porous if the outer shape is the same.

  Here, when examining the active material constituting the electrode, the active material is a porous or non-porous fine particle. Such fine particles adsorb a gas such as nitrogen gas, and the specific surface area is converted from the adsorbed amount. The mechanism by which the porous material adsorbs the gas is complicated, but the thickness plot method that simplifies and thinks to calculate the specific surface area is close to the experimentally obtained specific surface area. The thickness plot method referred to here, the so-called t method, compares the standard isotherm with adsorption and the adsorption isotherm, and converts the relative pressure to the thickness of the adsorption layer. Details are described in Non-Patent Document 2.

  If the substance is a simple sphere, square or the like, that is, if there is no hole or the like, in the graph of the thickness plot shown in FIG. 1, if it is isothermal, the volume V (vertical axis) of the gas is the gas adsorbed by the substance. It is proportional to the thickness t (horizontal axis).

  When gas is adsorbed to the porous active material, the gas adsorption volume per unit mass of the porous active material is adsorbed on the outer surface and the inner surface of the hole, and is laminated only on the outer surface when the inside of the hole is fully adsorbed. Will be adsorbed. Although there is a complicated change in the adsorption volume in details, the graph is generally a plot of the thickness t shown in FIG. The relationship with the adsorption volume V is that it is adsorbed on the outer surface and the inner surface of the hole when it is on a straight line passing through the origin at the start of adsorption, and becomes an inflection point P when the hole is fully adsorbed, and the gradient becomes gentle. It is shown that the film is adsorbed on the outer surface only.

  The specific surface area As is a value obtained by dividing the adsorption volume V by the thickness t, and is a parameter indicating that the degree of porosity is high if this value is large for the same material. The ratio Ao / As of the specific surface area As and the external surface area Ao is the external surface area Ao / (external surface area Ao + internal surface area). If 1 (Max), the internal surface area is 0. This parameter indicates that the value is large.

  In order to obtain the specific surface area, various quadrature methods represented by the BET adsorption formula have been proposed. Usually, a porous material such as activated carbon also measures the specific surface area by BET, but what is determined by BET is the total surface area, and in order to characterize the present invention, measurement by the so-called t method is preferable. In the active material used for the electrode constituting the present invention, it can be calculated by a single formula for the quadrature of the specific surface area of porous or non-porous, and is defined by the t method because it matches the properties and behavior of the active material. Specific surface area was adopted. In particular, the ions gathering on the outer surface of the active material express well the function as an electrode, and the action of ions on the inner surface is difficult to be transmitted to the outside, so the specific surface area of the t method matches the actual state.

This polymer transducer has a driving principle that an electric double layer is formed at the interface between an active material and a polymer solid electrolyte. Therefore, it is preferable from the viewpoint of performance as a transducer, particularly an actuator, that the active material has many interfaces capable of forming an electric double layer. From this point of view, the specific surface area of the active material, requirements 1 (specific surface area As, 100 m ² / g or higher) is required to meet, it is preferable that further is 200 meters ² / g or more, 300 meters ² / More preferably, it is g or more.

  The active material particles have a large surface area inside the active material particles, such as activated carbon that has been highly activated, and the electric double layer has no surface area inside the active material particles. The present inventors have found that the latter is superior in performance as an actuator as compared with the case where it is formed outside. From such a viewpoint, it is necessary that the relationship between all the specific surface areas As of the active material and the external surface area Ao of the active material particles satisfy the requirement 2 (the ratio Ao / As is 0.1 or more). Further, it is preferably 0.2 or more, and more preferably 0.3 or more.

Further, it is necessary to use a material having electron conductivity as the active material. The electron conductivity can be represented by volume resistivity. For example, the volume resistivity of a certain substance is an index of the volume resistivity as a substance bulk. The volume resistivity as the bulk material is preferably 10 ³ Ωcm or less, more preferably 10 ¹ Ωcm or less, from the viewpoint of the operation speed and energy efficiency of the actuator.

An active material that satisfies the above requirements can be used without limitation on the material, for example, single-walled carbon nanotube, multi-walled carbon nanotube, carbon nanohorn, carbon nanosheet (graphene sheet), polyacene, carbon fiber, vapor grown carbon fiber, ketjen black, High specific surface area carbon black such as Vulcan, carbon materials such as graphite, activated carbon, gold, platinum, silver, palladium, copper, nickel, aluminum, titanium, zinc, zirconium, iron, cobalt, tin, lead, indium, chromium, Metal materials such as molybdenum and manganese, indium-tin composite oxide (ITO), antimony-tin composite oxide (ATO), ruthenium oxide (RuO ₂ ), titanium oxide (TiO ₂ ), zinc oxide (ZnO), tin oxide _(SnO 2), iridium oxide _(IrO 2), oxidation Tan Sten _(WO 3), molybdenum oxide (MoO ₃₎ metal oxides such as zinc sulfide (ZnS), metal sulfides such as copper sulfide (CuS), poly (ethylene-3,4-dioxythiophene) (PEDOT) And conductive polymers such as polyaniline derivatives and polypyrrole derivatives.

  Among these, the active material is preferably a carbon-based material from the viewpoint of electrochemical stability and oxidation-reduction stability, and from the viewpoint of the performance of the polymer actuator, carbon nanotubes, high specific surface area carbon black, More preferred are carbon nanohorns and graphite. From the viewpoint of industrial economy, high specific surface area carbon black and carbon nanohorn are more preferable.

  One type of active material that satisfies the above conditions may be used, or a plurality of types may be used in combination. In the case of combining a plurality of types, there is no particular limitation, but generally about 2 to 5 types are preferable in terms of avoiding complication of the manufacturing process.

The electrode constituting the polymer transducer of the present invention may contain a conductive material, a binder, an ionic liquid, and the like in addition to the active material described above. Conductive material can be used to reduce the resistance of the electrode, for example, single-walled carbon nanotubes, multi-walled carbon nanotubes, carbon nanohorns, carbon nanosheets, carbon fibers, vapor grown carbon fibers, carbon black, graphite, etc. Materials, metal materials such as gold, platinum, palladium, copper, nickel, aluminum, titanium, zinc, zirconium, iron, cobalt, tin, lead, indium, chromium, molybdenum, manganese, indium-tin composite oxide (ITO), Antimony-tin composite oxide (ATO), ruthenium oxide (RuO ₂ ), titanium oxide (TiO ₂ ), zinc oxide (ZnO), tin oxide (SnO ₂ ), iridium oxide (IrO ₂ ), tungsten oxide (WO ₃ ) metal oxides such as molybdenum oxide (MoO _3), zinc sulfide (ZnS) Metal sulfides such as copper sulfide (CuS), poly (ethylene-3,4-dioxythiophene) (PEDOT), polyaniline derivatives, conductive polymers such as such as polypyrrole derivatives may be mentioned as examples.

  There is no restriction | limiting in particular in the shape of these electrically conductive materials, The thing of spherical shape, rugby ball shape, needle shape, fiber shape, flake shape, and nonwoven fabric shape is preferable. The amount of the conductive material used is not particularly limited, but is preferably 0.01 to 100 times the mass of the active material used in terms of conductivity and the ease of ion diffusion inside the electrode. 0.1 to 10 times is more preferable, and 0.2 to 5 times is more preferable.

  Examples of the binder include polyolefin resins such as polyethylene and polypropylene, polystyrene resins such as polystyrene and poly α-methylstyrene, polymethacrylic acid, polymethyl methacrylate, polybutyl methacrylate, polyacrylic acid, polymethyl acrylate, poly Poly (meth) acrylic resins such as ethyl acrylate and polybutyl acrylate, polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene random copolymer, polytetrafluoroethylene, polytri Halogenated vinyl resins such as fluoroethylene, polyester resins such as polyethylene glycol terephthalate, polyethylene glycol naphthalate, polybutylene glycol terephthalate, nylon-6, naphthalene Ron-6,6, Nylon-9T, Nylon-11, Nylon-12, Nylon-6,12 and other polyamide resins, thermoplastic polyurethane resins, polycarbonate resins, unsaturated polyesters, epoxy resins, alkyd resins, Thermosetting resins such as phenol resin, thermosetting polyurethane resin, natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber (styrene butadiene random copolymer), acrylic rubber, nitrile rubber, norbornene rubber, silicone rubber, Rubbers such as urethane rubber (including soft thermosetting polyurethane) or cross-linked products thereof, olefin-based thermoplastic elastomer (TPO), styrene-based thermoplastic elastomer (TPS), cross-linkable olefin-based thermoplastic elastomer (TPV), Acrylic heat Plastic elastomer (for example, block copolymer of polymethyl methacrylate and polybutyl acrylate, etc.), polyurethane thermoplastic elastomer (TPU), polyester thermoplastic elastomer (TPEE), polyamide thermoplastic elastomer (TPAE), etc. Examples thereof include thermoplastic elastomers and perfluorosulfonic acid polymers (for example, “Nafion” manufactured by DuPont).

  Among these, as a binder, from the viewpoint of film forming property, it is polyvinylidene fluoride, polytetrafluoroethylene, styrene-butadiene rubber, thermoplastic polyurethane resin, thermoplastic polyurethane elastomer, and a block copolymer described later. Is preferred. Further, from the viewpoint of the performance of the polymer transducer, the binder preferably contains an ionic liquid, and is preferably a polymer species that can be mixed with the ionic liquid. Although there is no restriction | limiting in particular in the usage-amount of a binder, it is preferable that it is 0.01-1000 times with respect to the mass of the active material to be used from a viewpoint of the resistance of an electrode and the ease of the spreading | diffusion of ion, and 0. 1 to 100 times is more preferable.

  Further, since the electrode layer needs to be in close contact with a non-aqueous solid polymer electrolyte described later, the electrode layer may be the same as or similar to the polymer constituting the solid polymer electrolyte.

  Although there is no restriction | limiting in particular about an ionic liquid, For example, the following general formula (I)-(V) can be mentioned as an example of the organic cation which comprises the suitable ionic liquid used in this invention.

(Ｉ)式中、Ｒ^１、Ｒ^２、Ｒ^３はそれぞれ独立に水素原子、または炭素数１〜１０の直鎖状または分岐状のアルキル基、炭素数１〜１０の直鎖状または分岐状のアルケニル基、炭素数６〜１５のアリール基、炭素数８〜２０のアラルキル基、炭素数２〜３０のオリゴアルケニレンオキシド基から選ばれる基を表す。

In formula (I), R ¹ , R ² and R ³ are each independently a hydrogen atom, a linear or branched alkyl group having 1 to 10 carbon atoms, or a linear or branched structure having 1 to 10 carbon atoms. A group selected from an alkenyl group, an aryl group having 6 to 15 carbon atoms, an aralkyl group having 8 to 20 carbon atoms, and an oligoalkenylene oxide group having 2 to 30 carbon atoms.

(II)式中、Ｒ^４は、水素原子、または炭素数１〜１０の直鎖状または分岐状のアルキル基、炭素数１〜１０の直鎖状または分岐状のアルケニル基、炭素数６〜１５のアリール基、炭素数８〜２０のアラルキル基、炭素数２〜３０のオリゴアルケニレンオキシド基から選ばれる基を、Ｒ'は炭素数１〜６の直鎖状または分岐状のアルキル基を、nは０以上５以下の整数を表す。

(II) In the formula, R ⁴ represents a hydrogen atom, a linear or branched alkyl group having 1 to 10 carbon atoms, a linear or branched alkenyl group having 1 to 10 carbon atoms, or a carbon number of 6 to A group selected from 15 aryl groups, aralkyl groups having 8 to 20 carbon atoms, and oligoalkenylene oxide groups having 2 to 30 carbon atoms, R ′ represents a linear or branched alkyl group having 1 to 6 carbon atoms, n represents an integer of 0 or more and 5 or less.

(III)式中、Ｒ^５、Ｒ^６、Ｒ^７、Ｒ^８はそれぞれ独立に水素原子、または炭素数１〜１０の直鎖状または分岐状のアルキル基、炭素数１〜１０の直鎖状または分岐状のアルケニル基、炭素数６〜１５のアリール基、炭素数８〜２０のアラルキル基、炭素数２〜３０のオリゴアルケニレンオキシド基から選ばれる基を表わし、Ｒ^５〜Ｒ^８のうち、２つの基が共同して環構造を形成していてもよい。

(III) In the formula, R ⁵ , R ⁶ , R ⁷ and R ⁸ are each independently a hydrogen atom, a linear or branched alkyl group having 1 to 10 carbon atoms, or a linear structure having 1 to 10 carbon atoms. Or a group selected from a branched alkenyl group, an aryl group having 6 to 15 carbon atoms, an aralkyl group having 8 to 20 carbon atoms, and an oligoalkenylene oxide group having 2 to 30 carbon atoms, and among R ^{5 to} R ⁸ , Two groups may jointly form a ring structure.

(IV)式中、Ｒ^９、Ｒ^１０、Ｒ^１１、Ｒ^１２はそれぞれ独立に水素原子、または炭素数１〜１０の直鎖状または分岐状のアルキル基、炭素数１〜１０の直鎖状または分岐状のアルケニル基、炭素数６〜１５のアリール基、炭素数８〜２０のアラルキル基、炭素数２〜３０のオリゴアルケニレンオキシド基から選ばれる基を表し、Ｒ^９〜Ｒ^１２のうち、２つの基が共同して環構造を形成していてもよい。

(IV) In the formula, R ⁹ , R ¹⁰ , R ¹¹ , and R ¹² are each independently a hydrogen atom, a linear or branched alkyl group having 1 to 10 carbon atoms, or a linear structure having 1 to 10 carbon atoms. Or a group selected from a branched alkenyl group, an aryl group having 6 to 15 carbon atoms, an aralkyl group having 8 to 20 carbon atoms, and an oligoalkenylene oxide group having 2 to 30 carbon atoms, and among R ^{9 to} R ¹² , Two groups may jointly form a ring structure.

(Ｖ)式中、Ｒ^１３、Ｒ^１４、Ｒ^１５はそれぞれ独立に水素原子、または炭素数１〜１０の直鎖状または分岐状のアルキル基、炭素数１〜１０の直鎖状または分岐状のアルケニル基、炭素数６〜１５のアリール基、炭素数８〜２０のアラルキル基、炭素数２〜３０のオリゴアルケニレンオキシド基から選ばれる基を表し、Ｒ^１３〜Ｒ^１４のうち、２つの基が共同して環構造を形成していてもよい。

(V) In formula, R <^13> , R <^14> , R < ¹⁵ > is a hydrogen atom or a C1-C10 linear or branched alkyl group each independently, C1-C10 linear or branched Represents a group selected from an alkenyl group, an aryl group having 6 to 15 carbon atoms, an aralkyl group having 8 to 20 carbon atoms, and an oligoalkenylene oxide group having 2 to 30 carbon atoms, and two groups among R ^{13 to} R ¹⁴ May jointly form a ring structure.

Among these, the imidazolium cation represented by the general formula (I) is preferable from the viewpoint of ion conductivity and availability of the ionic liquid. Among these, from the viewpoint of the melting point and viscosity of the ionic liquid, R ¹ and R ² in the general formula (I) are preferably a linear or branched alkyl group having 1 to 6 carbon atoms ^, More preferably, R ² is a different group. As an example of the most preferable organic cation, an ethylmethylimidazolium cation (EMI ⁺ ) can be mentioned.

Examples of anions constituting a suitable ionic liquid used in the present invention include halogen-containing anions, mineral acid anions, organic acid anions and the like. Specific examples of the halogen-containing anion or mineral acid anion include PF ₆ ⁻ , ClO ₄ ⁻ , CF ₃ SO ₃ ⁻ , C ₄ F ₉ SO ₃ ⁻ , BF ₄ ⁻ , (CF ₃ SO ₂ ) ₂ N ^{_{-, (C 2 F 5 SO}} 2) 2 N -, (CF 3 SO 2) 3 C -, AsF 6 - and the like can be given ^{_{-, SO 4 2-, (CN}} ) 2 N -, and NO ₃ . Examples of organic acid anions include RSO ₃ ⁻ , RCO ₂ ⁻ (where R is an alkyl group, allyl group, alkenyl group, aralkyl group, aralkenyl group, alkoxyalkyl group, acyloxyalkyl group, sulfoalkyl group, aryl group, or benzene). An aromatic heterocyclic residue such as a ring, naphthalene ring or anthracene ring, which may contain a plurality of cyclic structures or branched structures). Among these, PF ₆ ⁻ , ClO ₄ ⁻ , CF ₃ SO ₃ ⁻ , C ₄ F ₉ SO ₃ ⁻ , BF ₄ ⁻ , (CF ₃ SO ₂ ) ₂ from the viewpoint of ionic conductivity and availability of ionic liquids N ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ⁻ , (CN) ₂ N ⁻ are preferable, and in particular, BF 4 ⁻ , (CF ₃ SO ₂ ) ₂ N ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ^{− and the} like The sulfonylimide anion is preferred.

From the above, examples of the ionic liquid suitably used in the present invention include an ionic liquid composed of a combination of the above-described organic cation and anion. These may be used alone or in combination. Examples of preferred ionic liquids from the viewpoint of excellent ionic conductivity include ethylmethylimidazolium tetrafluoroborate (EMIBF ₄ ), ethylmethylimidazolium bis (trifluoromethanesulfonyl) imide (EMITFSI), butylmethylimidazolium tetrafluoro Examples thereof include borate (BMIBF ₄ ) and butylmethylimidazolium bis (trifluoromethanesulfonyl) imide (BMITFSI).

  The solid polymer electrolyte constituting the polymer transducer of the present invention comprises an ionic liquid and a polymer component. As the ionic liquid, those described for the electrode can be also used suitably. When an ionic liquid is used for the electrode, it is preferable to use the same ionic liquid for the polymer solid electrolyte.

  The polymer component that is a component of the polymer solid electrolyte can be used without particular limitation as long as it can hold the ionic liquid therein. For example, polyolefin resins such as polyethylene and polypropylene, polystyrene resins such as polystyrene and poly α-methylstyrene, polymethacrylic acid, polymethyl methacrylate, polyethyl methacrylate, polybutyl methacrylate, polyacrylic acid, polymethyl acrylate , Poly (meth) acrylic resins such as polyethyl acrylate and polybutyl acrylate, polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene random copolymer, polytetrafluoroethylene, Halogenated vinyl resins such as polytrifluoroethylene, polyethylene glycol terephthalate, polyethylene glycol naphthalate, polyester resins such as polybutylene glycol terephthalate, nylon-6, Nylon-6,6, Nylon-9T, Nylon-11, Nylon-12, Nylon-6.12 and other polyamide resins, thermoplastic polyurethane resins, polycarbonate resins, unsaturated polyesters, epoxy resins, alkyd resins, Thermosetting resins such as phenol resin, thermosetting polyurethane resin, natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber (styrene butadiene random copolymer), acrylic rubber, nitrile rubber, norbornene rubber, silicone rubber, Rubbers such as urethane rubber (including soft thermosetting polyurethane) or cross-linked products thereof, olefinic thermoplastic elastomer (TPO), styrenic thermoplastic elastomer (TPS), crosslinkable olefinic thermoplastic elastomer (TPV), Acrylic thermoplastic elastomer ( For example, polymethyl methacrylate and polybutyl acrylate block copolymers), polystyrene and poly (meth) acrylate block copolymers, polystyrene and amorphous polyester block copolymers, polyurethane thermoplastics Examples include elastomers (TPU), polyester-based thermoplastic elastomers (TPEE), thermoplastic elastomers such as polyamide-based thermoplastic elastomers (TPAE), and perfluorosulfonic acid polymers (for example, “Nafion” manufactured by DuPont). Can do.

  The polymer component may be a block copolymer of the polymers listed here or a graft copolymer. Among these, from the viewpoints of freedom of selection of the molding method, stability to heat, and low corrosivity to the electrode material, it is preferably a polymer that does not contain an ion dissociable group. From the viewpoint of the mechanical strength of the electrolyte, a copolymer having a polymer block that is incompatible with the ionic liquid to be used is more preferable, and the polymer block that is compatible with the ionic liquid to be used and the ionic liquid are incompatible. A block copolymer having a compatible polymer block is more preferable. The polymer component may be one kind or plural kinds, but usually 2 to 5 kinds are preferable in order to avoid complication of the production process.

  The mass ratio of the ionic liquid to the polymer component in the polymer solid electrolyte is not particularly limited, but from the viewpoint of ionic conductivity and mechanical strength, the ionic liquid is 1 part by mass or more and 1000 parts by mass with respect to 100 parts by mass of the polymer component. Part or less, preferably 10 parts by weight or more and 700 parts by weight or less, more preferably 20 parts by weight or more and 500 parts by weight or less.

  In the electrode and the polymer solid electrolyte, an antioxidant, a UV absorber, a lubricant, a dispersant, a surfactant, a filler, a reinforcing material, a plasticizer, etc. Preferably it is 40 mass parts or less with respect to 100 mass parts of electrolyte, More preferably, it is 30 mass parts or less, More preferably, you may contain 20 mass parts or less.

  The shape of the polymer transducer of the present invention is not particularly limited, but various shapes such as a film shape, a film shape, a sheet shape, a plate shape, a fiber shape, a columnar shape, a columnar shape, and a spherical shape are possible. In the case of manufacturing a film-like, film-like, sheet-like, or plate-like actuator, for example, in the method of producing these shapes, a sheet-like shape that is separately formed into a film-like shape is formed on the polymer solid electrolyte that is formed into a film-like shape. A method of bonding electrodes, a method of coating a solution or dispersion containing an electrode component on a polymer solid electrolyte formed into a film shape, casting a solution or dispersion containing an electrode component, and then attaching the polymer solid electrolyte Examples thereof include a method of casting the solution or dispersion liquid containing the electrode component, and further casting the solution or dispersion liquid containing the electrode component. The same method can be adopted in the case of a fiber shape, a columnar shape, a spherical shape, and the like.

  The polymer transducer of the present invention may be provided with a current collector for the purpose of reducing the resistance in the longitudinal direction. Examples of the current collector include metal foil such as gold, silver, copper, platinum, aluminum, nickel, and metal thin films, metal powder such as gold, silver, nickel, and carbon fine powder such as carbon powder, carbon nanotube, and carbon fiber. Examples thereof include a film-like molded body made of a binder resin, a fabric such as woven fabric, paper, and nonwoven fabric, and a polymer film formed with a metal thin film by a method such as sputtering or plating. Among these, from the viewpoint of flexibility, it is preferable that a metal thin film is formed on a film-like molded body, a fabric, a polymer film, or the like made of a metal powder and a binder resin.

  The polymer transducer can operate in air, water, vacuum, and organic solvents. Moreover, you may seal suitably according to a use environment. There is no restriction | limiting in particular as an example of sealing material, Various resin etc. can be mentioned.

  An example of using a polymer transducer as an actuator is shown in FIG. A force, fluctuation, and displacement are generated by applying a potential difference through terminals 12 and 13 between electrodes that are in contact with each other with the polymer solid electrolyte of the polymer transducer 10 sandwiched therebetween and insulated from each other. The electrode itself in contact with the polymer solid electrolyte of the polymer transducer 10 serves as a trigger member of the actuator to drive the load cell 18.

  On the other hand, when a deformation and / or pressure is applied to the polymer transducer from the outside, a potential difference (voltage) is generated between the mutually insulated electrodes, so that it is used as a displacement sensor for detecting fluctuation, deformation and / or pressure. You can also.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated further more concretely, this invention is not limited at all by these.

<Various measurements and calculations>
(1) Measurement of specific surface area As and external surface area Ao Using BELSORP 18 manufactured by Nippon Bell Co., Ltd., measurement was performed by the t method based on an adsorption isotherm of 77K obtained using nitrogen gas as a probe gas. Specifically, As was calculated from the initial inclination of the straight line portion passing through the origin, and Ao was calculated from the inclination of the straight line after the inflection point P changed and the inclination changed.

(2) Measurement of Generating Force as Actuator As shown in FIG. 3, for the polymer transducer 10 cut to a size of 15 mm × 5 mm, 10 mm in the length direction is sandwiched between the gold terminal 12 and the gold terminal 13 and used as an actuator. An operating length of 5 mm was taken out into the air to form a measurement cell. A potentiostat 15 (HAB-151 made by Hokuto Denko) connected with a function generator 16 (Hokuto Denko's function generator HB-211) was connected to the gold terminals 12 and 13. The gold terminal 12 is a working electrode, and the gold terminal 13 is a counter electrode, that is, a reference electrode. The load cell 18 (UL-10GR manufactured by Minebea Co., Ltd.) was arranged so that the probe was in contact with the position P of 1 mm from the tip of the actuator (the part of the polymer transducer 10 exposed to the air). In this state, a predetermined voltage was applied from the potentiostat 15. Alternatively, the actuator 10 is operated by applying a pulse voltage through the function generator 16 as necessary. In this operation, the generated force was recorded by the load cell 18.

(3) Calculation of the amount of stored electricity In the actuator test, the amount of stored electricity was calculated by integrating the time-current curve detected by the potentiostat 15.

<Materials used>
(1) Ketjen Black: “Ketjen Black EC” sold by Lion Corporation was used as it was.
(2) Single-walled carbon nanotube (SWCNT): “Purified HiPco” manufactured by Carbon Nanotechnology Inc. was used as it was.
(3) Ruthenium oxide (RuO ₂ )
“Ruthenium (IV) oxide, Electronic Grade, Premion (R), 99.95%” purchased from Alfa Aesar was used as it was.
(4) Carbon nanohorn: “Carbon nanohorn” manufactured by NEC was used as it was.
(5) Silver flake: “S-300” manufactured by Daiken Chemical Co., Ltd. was used as it was.
(6) Acetylene black: Denka Black (registered trademark) manufactured by Denki Kagaku Co., Ltd. is used.
(7) Activated carbon: “YP-17D” manufactured by Kuraray Chemical Co. was used as it was.
(8) Ethylmethylimidazolium bis (trifluoromethylsulfonyl) imide (EMITFSI): The product made by Nippon Synthetic Chemical Co., Ltd. was used as it was.
(9) Ethylmethylimidazolium tetrafluoroborate (EMIBF4): The product made by Nippon Synthetic Chemical Co., Ltd. was used as it was.
(10) Vinylidene fluoride-hexafluoropropylene random copolymer (P (VDF / HFP)): Uses “Kyner # 2801” purchased from Arkema.
(11) Nafion membrane: The Nafion 117 membrane (manufactured by DuPont) was used as it was.
(12) Nafion dispersion solution: “5% Nafion dispersion solution DE520 CS type” obtained from Wako Pure Chemical Industries, Ltd. was used as it was.
As other materials and reagents, commercially available products that were purified according to a conventional method if necessary were used.

<Example of member production>
(1) Preparation of solid polymer electrolyte Nafion 117 was cut to a size of 6 cm x 6 cm, boiled and washed with 1 mol / L sulfuric acid for 1 hour, then thoroughly washed with water, and then an aqueous lithium chloride solution (1 g / L) The mixture was boiled for 1 hour to neutralize sulfonic acid groups. This was dried at 150 ° C. overnight, then immersed in EMIBF 4 and impregnated at 150 ° C. for 3 hours. This membrane was sufficiently vacuum-dried to obtain a polymer solid electrolyte having a thickness of about 190 μm.

(2) Production of electrode film A predetermined amount of active material (Ketjen black, single-walled carbon nanotube, ruthenium oxide, carbon nanohorn) and a conductive material are weighed in a sample bottle, if necessary, and a binder solution (Nafion) In the case of (3), a commercially available dispersion was added, and in the case of using P (VDF / HFP) / EMITFSI, an N-methylpyrrolidone solution of this mixture was used. When the viscosity was too high and stirring was difficult, the solvent was further added to adjust the viscosity. The dispersion thus prepared was irradiated with ultrasonic waves at room temperature for 12 hours, and then poured into a mold of a predetermined size and cast to obtain an electrode film.

<Examples 1-4> Polymer Transducer The polymer solid electrolyte prepared in Preparation Example (1) is sandwiched between two electrode films prepared in Preparation Example (2), and in this state for 10 minutes at 130 to 200 ° C. The polymer transducer was bonded by hot pressing at a temperature appropriately selected between them.

For the polymer transducer of Example 1, an electrode film using ketjen black as an active material was used. In the polymer transducer of Example 2, an electrode film using single-walled carbon nanotubes as an active material was used. The polymer transducer of Example 3 used an electrode film using ruthenium oxide (RuO ₂ ) as an active material. The polymer transducer of Example 4 used an electrode film using carbon nanohorn as an active material.

  About the polymer transducer of Examples 1-4, the performance as an actuator was evaluated. The results are shown in Table 1. In addition, since the performance of the actuator, that is, the generated force depends on the filling amount of the active material, a value obtained by dividing the generated force after 180 seconds by the charged amount after 180 seconds was calculated as a comparison. The higher this value, the greater the amount of work with a smaller amount of electricity stored, and the higher the performance as an actuator.

Comparative Examples 1 and 2 Polymer Transducer Polymer transducers of Comparative Examples 1 and 2 were prepared using different active materials, and the performance as an actuator was evaluated in the same manner as in Examples 1 to 4. The results are shown in Table 1.

  From the above results, when the polymer transducer of the present invention is used as an actuator, the generated force is greatly superior to those of Comparative Examples 1 and 2, and the generated force value per unit charged amount is also large, and the actuator is excellent in efficiency. It can be seen that it is. Although Comparative Example 1 satisfies the requirement 2 of the present invention, since the requirement 1 is not satisfied, it can be seen that the performance as an actuator is greatly inferior. The comparative example 2 satisfies the requirement 1 of the present invention, but does not satisfy the requirement 2, so that the actuator performance is low and the efficiency is inferior.

The graph of the plot with respect to thickness t of the volume V of the gas adsorb | sucked by the active material of a simple shape without a hole. The graph of the plot with respect to the thickness t of the volume V of the gas adsorbed by the porous active material. It is the schematic of the apparatus used in the operation | movement test of the actuator to which this invention is applied.

Explanation of symbols

  10 is an actuator, 12 and 13 are gold terminals, 15 is a potentiostat, 16 is a function generator, and 18 is a load cell.

Claims (4)

A polymer transducer comprising a polymer solid electrolyte comprising an ionic liquid and a polymer component and electrodes which are in contact with each other and are insulated from each other, wherein at least one of the electrodes is porous A high active material having a specific surface area As of at least 100 m ² / g and a ratio Ao / As of the specific surface area As to the external surface area Ao of at least 0.1. Molecular transducer.   2. The polymer transducer according to claim 1, wherein the specific surface area As is a value obtained by a thickness plot method (t method).   3. The polymer transducer according to claim 1, wherein the main constituent element of the active material is carbon.   A polymer actuator comprising the polymer transducer according to claim 1 as a drive unit.

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