JP6870835B2 - Stacked actuator - Google Patents

Description

The present invention relates to a laminated actuator.

As an actuator element that can operate in the air or in a vacuum, an actuator that uses a gel of carbon nanotubes (hereinafter, may be abbreviated as "CNT") and an ionic liquid as a conductive elastic active layer has been proposed. (Patent Document 1).

Further, those using a conductive auxiliary agent to improve the performance of the actuator (Patent Document 2) and those using CNT and carbon nanohorn (CNH) in combination (Patent Document 3) have been proposed.

The structure of a conventional actuator element uses a gel of a conductive material such as carbon nanotube, Nafion (registered trademark), or a conductive polymer as an elastic active layer and an ionic liquid, and an electrode using the ionic liquid gel as an electrolyte layer. It has a sandwich structure with layers. Actuator performance is mainly evaluated by two parameters, displacement amount and stress, but it is difficult to improve or improve these two parameters at the same time.

Patent Document 4 discloses a laminated actuator in which a plurality of actuators are laminated, and describes that a sheet having a low friction coefficient is preferable as an insulating layer in order to reduce the friction applied between the actuator and the sheet when the actuator is driven. Since such an insulating sheet hinders the drive of the actuator, it is difficult to improve the displacement amount and the stress at the same time.

JP-A-2005-176428 WO2009 / 157491 WO2010 / 029992 JP 2010-068678

An object of the present invention is to improve the displacement amount and stress of the actuator at the same time.

The present invention provides the following laminated actuators.
Item 1. A laminated actuator including a plurality of polymer actuator units and one or a plurality of insulating materials, wherein the insulating material is sandwiched between the polymer actuator units, and the insulating material is composed of a non-woven fabric of organic polymer fibers. Laminated actuator.
Item 2. Item 2. The laminated actuator according to Item 1, wherein the organic polymer fiber has an average diameter of less than 1000 nm.
Item 3. Item 3. The laminated actuator according to Item 1 or 2, wherein the organic polymer is a fluoropolymer.
Item 4. Item 2. The laminated actuator according to any one of Items 1 to 3, wherein the polymer actuator unit contains nanocarbon.
Item 5. Item 2. The laminated actuator according to any one of Items 1 to 4, wherein the polymer actuator unit has a structure in which an electrolyte layer is sandwiched between two electrode layers.

According to the present invention, it is possible to obtain an actuator in which the displacement amount and the stress are simultaneously improved as compared with the actuator unit.

By using the above-mentioned organic polymer fiber non-woven fabric as the laminated member, the electrode layer of the polymer actuator unit and the fibers constituting the organic polymer fiber non-woven fabric are in a bonded state. From this, each polymer actuator unit is driven with the organic polymer fibers adhering to the electrode surface when the laminated actuator is driven. However, since the friction between the fibers is small for the polymer fibers constituting the organic polymer fiber non-woven fabric, the friction between the fibers is small. It deforms easily. As a result, an effect that does not interfere with the driving of adjacent actuators is produced.

Schematic and description showing laminated actuators It is the schematic which shows the actuator unit (actuator A) and the laminated actuator. The outline of the measurement of the displacement amount by the laser displacement meter is shown. Shows the relationship between the number of stacked actuators and the amount of displacement The relationship between the number of stacked actuators and the shrinkage rate is shown. The relationship between the number of stacked actuators and the generated force is shown. SEM photograph of electrospun non-woven fabric using PVDF-HFP. From FIG. 7, it can be seen that the fibers are not fused together. Therefore, the friction is small and the structure is suitable for the laminating member.

As the polymer actuator unit of the present invention, for example, an electrolyte membrane layer (ion conductive layer) is sandwiched between both sides of the electrolyte membrane layer (electrode layer) containing carbon nanotubes, an ionic liquid, and a polymer (electrode layer). A three-walled structure of − (ionic conductive layer) − (electrode layer) can be mentioned, and in order to increase the surface conductivity of the electrode, a conductive layer is further formed on the outside of the electrode layer (conductive layer) − (electrode). The actuator unit may have a five-layer structure of (layer)-(ionic conduction layer)-(electrode layer)-(conductive layer).

In order to form an electrode layer on the surface of the electrolyte membrane layer to obtain an actuator unit, the electrode layer may be pressure-bonded to the surface of the electrolyte membrane layer. The crimping may be performed under heating or at room temperature.

The laminated actuator of the preferred embodiment of the present invention assumes an actuator as shown in FIG. 1 which can be manufactured by sandwiching an insulating material between polymer actuator units and crimping them. When the laminated actuator has 3 or more polymer actuator units and 2 or more insulating materials, they may be crimped step by step, or all polymer actuator units and all insulating materials may be overlapped and crimped together. Good.

In the present invention, a laminated actuator can be obtained by sandwiching an insulating material between adjacent actuator units. The number of actuator units included in the laminated actuator may be 2 or more, and examples thereof include about 2 to 100. Since the insulating material is sandwiched between the actuator units, the number of insulating materials may be one less than the number of actuator units.

In a preferred embodiment of the invention, the electrode layer is composed of a polymeric gel containing a conductive material, an ionic liquid and a polymer. Examples of the conductive material include nanocarbon, a fluorine-based polymer having a sulfonic acid group, and a conductive polymer, and these may be used alone or in combination of two or more. Examples of nanocarbons include carbon nanohorns (CNH), carbon nanotubes (CNT), carbon nanofibers (CNF), carbide delivered carbon (CDC), graphene, graphene nanoribbons, and graphene nanoplates. Examples of the fluorine-based polymer having a sulfonic acid group include Nafion (registered trademark). Conductive polymers include polyacetylene, polyaniline, polythiophene, polypyrrole, polyfluorene, polyphenylene, polyphenylene sulfide, poly (1,6-heptadiyne), polybiphenylene (polyparaphenylene), polyparaphenylene sulfide, polyphenylacetylene, poly. (2,5-thienylene), polyindole, poly-2,5-diaminoanthraquinone, poly (o-phenylene sulfide), poly (quinolinium) salt, poly (isoquinolinium) salt, polypyridine, polyquinoxaline, polyphenylquinoxalin, etc. Can be mentioned. The electrolyte membrane also contains an ionic liquid and a polymer.

The carbon nanotubes used in the present invention are carbon-based materials having a shape in which a graphene sheet is wound into a cylinder, and are roughly classified into single-walled nanotubes (SWNTs) and multi-walled nanotubes (MWNTs) according to the number of constituent walls thereof. Further, various types are known, such as being divided into a chiral type, a zigzag type, and an armchair type according to the difference in the structure of the graphene sheet. In the present invention, any type of carbon nanotube can be used as long as it is such a so-called carbon nanotube. As carbon nanotubes, use HiPco (manufactured by Unidim), which can be relatively mass-produced using carbon monoxide as a raw material, and carbon nanotubes (SG) synthesized by the super growth method, which can be obtained by the National Institute of Advanced Industrial Science and Technology. Can be done.

The aspect ratio of carbon nanotubes used in the present invention is preferably 10 ³ or more. The length of the carbon nanotubes is not particularly limited, but ordinary carbon nanotubes of about 1 μm or less may be used, and carbon nanotubes longer than 1 μm, for example, longer carbon nanotubes of about 10 μm to 30 μm may be used. Further, in the case of carbon nanotubes synthesized by the super growth method, carbon nanotubes of 50 μm or more, further 200 μm or more, particularly 500 μm or more can be obtained, so such long carbon nanotubes can also be used. The upper limit of the length of the carbon nanotube is not particularly limited, but is, for example, about 10 mm.

Carbon nanohorns are carbon nanoparticles that have a shape in which a graphite sheet is rolled into a cone and the tip is closed in a conical shape. Commercially available products can be used as the carbon nanohorn.

The carbon nanofiber (CNF) used in the present invention is a carbon fiber having a lower limit of diameter of about 150 nm and an upper limit of diameter of about 500 nm. The lower limit of the length of CNF is about 10 μm, and the upper limit is about 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm, or 1000 μm.

CNF uses an aromatic mesophase pitch as the carbon precursor polymer, melt-spins a polymer blend in which it is dispersed in a matrix polymer, and then melt-spins the spun fiber, carbonizes and heats it, and further activates it if necessary, graphite. It can be produced by chemical treatment. CNF activated by activation treatment is called ACNF (activated CNF). As such a CNF, for example, carbon nanofiber manufactured by Teijin Limited can be preferably exemplified.

A conductive auxiliary agent may be further added to the electrode layer. Further, the oil and fat may be blended inside the electrode layer, or the oil and fat layer may be provided between the electrode layer and the electrolyte membrane layer.

Examples of the conductive auxiliary agent include mesoporous inorganic materials, metal oxides, carbon particles, gold fine particles, and the like.

Mesoporous inorganic materials include silica, titania, zirconia, alumina, silica-alumina, silica-titania, tin phosphate, niobium phosphate, aluminum phosphate, titanium phosphate, and their oxides, nitrides, and sulfides. Examples thereof include selenium compounds, tellurides and composite oxides, and composite salts. Examples of the metal oxide include titanium oxide, zinc oxide, tin oxide, aluminum oxide, ruthenium oxide and the like. Examples of carbon particles include carbon black, ketjen black, acetylene black, artificial graphite, carbon fiber, furnace black, channel black, lamp black, and thermal black.

Oils and fats include salad oil, white squeezed oil, corn oil, soybean oil, sesame oil, rapeseed oil, rice bran oil, bran oil, camellia oil, Benibana oil, palm kernel oil, palm oil, cottonseed oil, sunflower oil, sesame oil, olive oil, and peanut oil. , Almond oil, avocado oil, hazelnut oil, walnut oil, grape seed oil, mustard oil, lettuce oil, fish oil, whale oil, shark oil, liver oil and other fatty oils, cacao butter, palm oil, lard, beef, chicken oil, At room temperature solid fats such as sheep fat, horse fat, shortening, milk fat, butter, margarine, gee, hardened oil, lubricating oil, castor oil, grease, cutting oil, glycerin fatty acid ester, polyglycerin fatty acid ester, sucrose fatty acid ester. , Ethylene fatty acid ester, propylene glycol fatty acid ester, sorbitan fatty acid ester, polyoxyethylene fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, polyoxyethylene lanolin fatty acid ester, trimethylolpropan fatty acid ester, beeswax, rice Wax, hydrogenated processed fats and oils, polyglycerin condensed (poly) ricinoleic acid ester, phospholipids, lecithin, egg yolk lecithin, lysolecithin, soybean lecithin, organic acid monoglyceride, polyoxyethylene alkyl ether, polyoxyethylene castor oil, sodium stearoyl lactate, Stearoyl calcium lactate, saponin, kiraya saponin, succinic acid monoglyceride, succinic acid diglyceride and the like can be mentioned.

The ionic liquid used in the present invention is also referred to as a room temperature molten salt or simply a molten salt, and is a salt that exhibits a molten state in a wide temperature range including room temperature (room temperature), for example, 0. A salt that exhibits a molten state at ° C., preferably −20 ° C., more preferably −40 ° C. Further, the ionic liquid used in the present invention preferably has high ionic conductivity.

In the present invention, various known ionic liquids can be used, but stable ones that exhibit a liquid state at room temperature (room temperature) or a temperature close to room temperature are preferable. Suitable ionic liquids used in the present invention consist of cations (preferably imidazolium ions, quaternary ammonium ions) represented by the following general formulas (I) to (IV) and anions (X ⁻ ). Things can be mentioned.

In the above formulas (I) to (IV), R contains an alkyl group or an ether bond having a linear or branched carbon number of 1 to 12, and the total number of carbon and oxygen is 3 to 12 linear or branched. In formula (I), R ¹ represents a linear or branched alkyl group or hydrogen atom having 1 to 4 carbon atoms. In formula (I), ^{it is preferable that R and R 1} are not the same. In formulas (III) and (IV), x is an integer of 1 to 4, respectively. In formulas (III) and (IV), the two R groups may be combined to form a 3- to 8-membered, preferably 5- or 6-membered aliphatic saturated cyclic group.

Alkyl groups having a linear or branched carbon number of 1 to 12 include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, pentyl, hexyl, heptyl, octyl, and the like. Groups such as nonyl, decyl, undecyl, and dodecyl can be mentioned. The number of carbon atoms is preferably 1 to 8, and more preferably 1 to 6.

Examples of the alkyl group having a linear or branched carbon number of 1 to 4 include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and t-butyl.

Alkyl groups having an ether bond and a linear or branched total number of carbon and oxygen of 3 to 12 include CH ₂ OCH ₃ , CH ₂ CH ₂ OCH ₃ , CH ₂ OCH ₂ CH ₃ , and CH ₂ CH _2. OCH ₂ CH ₃ , (CH ₂ ) _p (OCH ₂ CH ₂ ) _q OR ² (where p is an integer of 1 to 4, q is an integer of 1 to 4, R ² is CH ₃ or C ₂ H ₅ Represents).

Anion (X ^-) as the tetrafluoroborate ion _{^{(BF 4 -), BF 3}} CF 3 -, BF 3 C 2 F 5 -, BF 3 C 3 F 7 -, BF 3 C 4 F 9 -, hexa fluorophosphate ion (PF ₆ ^-), bis (trifluoromethanesulfonyl) imide ion _{((CF 3 SO 2) 2} N -), bis (trifluoromethanesulfonyl) imide ion ^{_{((FSO 2) 2 N -}} ), bis (pentafluorophenyl ethanesulfonyl) imide ion _{((CF 3 CF 2 SO 2} ) 2 N -), ( trifluoromethane sulfonyl) (trifluoromethanesulfonyl) imide ion _{((FSO 2) (CF 3} SO 2) N -), perchlorate ion (ClO ₄ ^-), tris (trifluoromethanesulfonyl) carbon acid ion _{(CF 3 SO 2) 3 C} -), trifluoromethanesulfonate ion (CF ₃ SO ₃ ^-), dicyanamide ion ((CN) ₂ N ^-), trifluoroacetate ion (CF ₃ COO ^-), organic carboxylic acid ions and halogen ions can be exemplified.

Among these, as the ionic liquid, for example, the cation is 1-ethyl-3-methylimidazolium ion, 1-butyl-3-methylimidazolium ion, [N (CH ₃ ) (CH ₃ ) (C ₂ H _5). ) (C ₂ H ₄ OC ₂ H ₄ OCH ₃ )] ⁺ , [N (CH ₃ ) (C ₂ H ₅ ) (C ₂ H ₅ ) (C ₂ H ₄ OCH ₃ )] ⁺ , anion is halogen ion, tetrafluoroborate, bis (trifluoromethanesulfonyl) imide ion _{((CF 3 sO 2) 2} N -), trifluoromethanesulfonate ion (CF ₃ sO ₃ ^-) ones are specifically exemplified. It is also possible to use two or more cations and / or anions to further lower the melting point.

However, the combination is not limited to these, and any ionic liquid having a conductivity of 0.1 Sm ^-1 or more can be used.

The electrolyte membrane layer (ionic conduction layer) of the present invention is prepared by preparing a solution containing a polymer, a solvent and, if necessary, an ionic liquid, forming a film of the obtained solution by a casting method, and evaporating and drying the solvent. Can be obtained by The electrolyte membrane can be formed by coating, printing, extrusion, casting, injection, or the like. Here, the solvent may be a mixed solvent of a hydrophilic solvent and a hydrophobic solvent.

Examples of the hydrophilic solvent include carbonates such as ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, methylethyl carbonate, propylene carbonate and butylene carbonate, ethers such as tetrahydrofuran, and carbon atoms 1 to 3 such as acetone, methanol and ethanol. Examples of lower alcohols, acetonitrile, N, N-dimethylacetamide, N-methyl-2-pyrrolidone and other amides. Examples of the hydrophobic solvent include ketones having 5 to 10 carbon atoms such as 4-methylpentane-2-one, halogenated hydrocarbons such as chloroform and methylene chloride, and aromatic hydrocarbons such as toluene, benzene and xylene. Examples thereof include aliphatic or alicyclic hydrocarbons such as hexane and cyclohexane.

In the present invention, the polymer used for the electrode layer and the electrolyte membrane layer is a copolymer of a fluorinated olefin having a hydrogen atom such as a polyvinylidene fluoride-hexafluoropropylene copolymer [PVDF (HFP)] and a perfluorinated olefin. , Homopolymer of fluorinated olefin having hydrogen atom such as polyvinylidene fluoride (PVDF), perfluorosulfonic acid (Nafion), poly-2-hydroxyethyl methacrylate (poly-HEMA), polymethyl methacrylate (PMMA), etc. Poly (meth) acrylates, polyethylene oxide (PEO), polyacrylonitrile (PAN) and the like can be mentioned. This polymer does not include conductive polymers such as polyaniline.

The insulating material of the present invention is composed of a non-woven fabric of organic polymer fibers. The insulating material is preferably a lightweight, stretchable (deformable), thin-film non-woven fabric with low friction between the organic polymer fibers constituting the non-woven fabric. If the structure of the insulating material is a sheet in which the polymer chains are firmly bonded to each other, the friction between the polymer chains becomes large. Therefore, even if the friction between each polymer actuator unit and the surface of the insulating material is small, the result is Inhibits the displacement of the actuator.

The organic polymer constituting the non-woven fabric preferably has low friction, is soluble in a solvent, and is insoluble in water and ionic liquids. Specific examples of the organic polymer include polyolefins, polystyrenes, polyvinyl chlorides, fluorine-based polymers, and the like, and fluorine-based polymers are preferable. Examples of the polyolefin include polyethylene, polypropylene, polybutene, and copolymers thereof. Fluorine-based polymers include ethylene fluorinated propylene, a copolymer of tetrafluoroethylene, hexafluoropropylene and vinylidene fluoride (THV), a copolymer of ethylene and tetrafluoroethylene, ethylene chlorotrifluoroethylene, and polyvinylidene fluoride. , A copolymer of a fluorinated olefin having a hydrogen atom such as polyvinylidene fluoride-hexafluoropropylene copolymer [PVDF (HFP)] and a perfluorinated olefin, fluorination having a hydrogen atom such as polyvinylidene fluoride (PVDF) Examples include homopolymers of olefins, blends and derivatives thereof. A preferred fluoropolymer is a copolymer of a fluorinated olefin having a hydrogen atom such as a polyvinylidene fluoride-hexafluoropropylene copolymer [PVDF (HFP)] and a perfluorinated olefin.

The average diameter of the organic polymer fiber is about 200 to 1000 nm, preferably about 500 to 750 nm.

The thickness of the insulating material (nonwoven fabric of organic polymer fiber) is preferably about 0.5 to 100 μm, preferably about 1 to 50 μm, and more preferably about 2 to 20 μm.

The bulk density of the insulating material is 0.1 to 1 g / cm ³ , preferably 0.2 to 0.7 g / cm ³ , and more preferably about 0.45 to 0.55 g / cm ³ .

The porosity of the insulating material is 50-90%, preferably 60-80%, more preferably about 70-75%.

The non-woven fabric of the organic polymer fiber may be produced by a melt blown method, a spunbond method, a papermaking method or the like, but is preferably produced by an electric field spinning method.

The electric field spinning method is a method of electrically spinning fibers by applying a high voltage to a spinning stock solution.

The electric field spinning method has an advantage that it can be manufactured by a simple device and can be obtained as a non-woven fabric in which ultrafine fibers are bonded to each other. The non-woven fabric obtained by the electrolytic spinning method is preferable because it is lightweight, has elasticity, and can be made thin. In addition, by selecting the material, it is possible to produce a non-woven fabric with low friction between fibers. The electrospun non-woven fabric can be easily carried out by those skilled in the art using an electrolytic spinning apparatus.

In a preferred embodiment of the invention, the electrode layer of the actuator unit comprises a conductive material, a polymer, an ionic liquid. The preferable mixing ratio of the conductive material, the polymer, and the ionic liquid in the electrode layer is that the total amount thereof is 100% by mass.
Conductive material:
1-98% by mass, preferably 23-66% by mass, more preferably 23-50% by mass;
polymer:
1-98% by mass, preferably 17-50% by mass, more preferably 17-40% by mass;
Ionic liquid:
1-98% by mass, preferably 17-80% by mass, more preferably 17-60% by mass;
Is.

The formation of the electrode layer can be carried out by a method such as coating, printing, extrusion, casting, or injection of a mixed solution containing a conductive material, a polymer, and an ionic liquid together with a solvent, and is preferably carried out by casting.

The thickness of the electrolyte membrane layer is preferably 5 to 200 μm, more preferably 10 to 100 μm. The thickness of the electrode layer is preferably 10 to 500 μm, more preferably 50 to 300 μm. Further, spin coating, printing, spraying and the like can also be used for forming the film of each layer. Further, an extrusion method, an injection method and the like can also be used.

The electrode layer may be composed of a single thin film, or a plurality of thin films may be laminated by pressure bonding or the like.

When a DC voltage of 0.5 to 4 V is applied between the electrodes (the electrodes are connected to the electrode layer), the laminated actuator thus obtained has a unit length (from the fixed end of the electrode to the tip) within a few seconds. It is possible to obtain a displacement of about 0.05 to 1 times that of the movable part). Further, this actuator unit can be flexibly operated in air or vacuum.

According to the actuator unit that can be obtained by the above method, it is possible to obtain a unit that has good responsiveness, a large amount of deformation, and is durable in air or vacuum. Moreover, the structure is simple, miniaturization is easy, and it can be operated with a small amount of electric power.

Since the actuator unit of the present invention operates with good durability in air or vacuum and flexibly operates at a low voltage, the actuator of a robot that comes into contact with a person who needs safety (for example, a home robot, a pet robot, etc.) Actuators for personal robots such as amusement robots), robots that work in special environments such as space environment, vacuum chamber use, rescue robots, medical and welfare robots such as surgical devices and muscle suits, and even micro It is most suitable as an actuator for machines and the like.

In particular, in the production of materials in a vacuum environment or an ultra-clean environment, there is an increasing demand for actuators for transporting and positioning samples in order to obtain high-purity products, and ionic liquids that hardly evaporate are used. The laminated actuator of the present invention can be effectively used as an actuator for a process in a vacuum environment as an actuator without fear of contamination.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.
Example 1
Weight of single-walled carbon nanotubes (hereinafter referred to as SWNTs), carbon nanohorns (manufactured by NEC, trade name CNHox, hereinafter referred to as CNH), and 1-ethyl-3-methylimidazolium-tetrafluoroborate (hereinafter referred to as EMIBF ₄ ). A polyvinylidene fluoride-hexafluoropropylene copolymer (manufactured by Archema, trade name KYNAR2801, hereinafter referred to as PVDF-HFP) is formed between two electrode films (thickness 74 μm) composed of a ratio of 1: 1: 6. An _{electrolyte membrane layer (thickness 12 μm) in which EMIBF 4} is composed of a weight ratio of 1: 1 is sandwiched, ^{and heat pressure bonding is performed under the conditions of 70 ° C., 0.5 N / mm 2} , and 10 minutes, and an actuator as shown in FIG. 2 is performed. A was obtained (Fig. 2). The thickness of the actuator A was 152 μm.

A laminating member made of a non-woven fabric of PVDF-HFP having a film thickness of 10 μm produced by an electric field spinning method is sandwiched between the ^two actuators A, and pressure-bonded at room temperature for a few minutes at 0.1 N / mm. B was obtained (Fig. 2). The thickness of the laminated actuator B was 306 μm. The bulk density of the non-woven fabric of PVDF-HFP was 0.5 g / cm ³ . Further, since the density of the resin (PVDF-HFP) was 1.76 to 1.79 g / cm ³ , the porosity was about 72% (filling rate was about 28%). An SEM photograph of the non-woven fabric (insulating material) of PVDF-HFP is shown in FIG.
Comparative Example 1
A laminating member made of a PVDF-HFP film having a film thickness of 6 μm produced by a solvent casting method is sandwiched between the ^two actuators A, and pressure-bonded under the conditions of room temperature, 0.1 N / mm for a few minutes, and the laminated actuator C. Got
Comparative Example 2
The PVDF-HFP film having a thickness of 6μm was prepared by solvent casting superimposed on the actuator A, to obtain room temperature and the pressure bonding under the conditions of 0.1 N / ^mm 2, 3 minutes actuators D'. The two actuators D'2 were arranged so that the PVDF-HFP film sides faced each other, and were brought into close contact with each other via a lubricating oil (liquid paraffin) to obtain a laminated actuator D.

The amount of deformation of the actuator when the actuator A and the laminated actuators B, C, and D are attached to the electrode jigs and a rectangular wave voltage having a frequency of 0.01 Hz and ± 2 V is applied between the electrode jigs. A laser was irradiated to a position 5 mm from the distance, and measurement was performed using a laser displacement meter (LC2100 manufactured by Keyence Co., Ltd.) (FIG. 3).

Table 1 shows the relative values of the deformation amount of each actuator and the deformation amount of the laminated actuators B, C, and D when the deformation amount of the actuator A is 100%.

Ideally, even when a plurality of actuators are stacked, the amount of deformation is equivalent to the amount of deformation of a single actuator. That is, it can be said that the closer the deformation amount shown in Table 1 is to the value of the actuator A, the more suitable the laminating member used for the laminating member is for laminating the actuator.

Comparing the deformation amounts of the laminated actuator B and the laminated actuator C in Table 1, since the laminated actuator B shows a larger value, even a member made of the same PVDF-HFP is more than a film produced by the casting method. It can be seen that the non-woven fabric produced by the electrospinning method is superior as a laminating member.

In particular, since the amount of deformation of the laminated actuator B is almost the same as 84% of the amount of deformation of the actuator A, it can be seen that the PVDF-HFP non-woven fabric produced by the electrospinning method is particularly excellent as a laminating member.
Example 2
_{An electrolyte membrane layer in which PVDF-HFP and EMIBF 4} are composed of a weight ratio of 1: 1 between two electrode membranes (thickness: 80 μm) in which SWNTs, CNH, and EMIBF ₄ are composed of a weight ratio of 1: 1: 7. Actuator E was obtained by heat-pressing under the conditions of 70 ° C., 0.5 N / mm ^{2, and 10 minutes with (thickness 12 μm) sandwiched between them.} The thickness of the actuator E was 163 μm.

The piling member consisting of nonwoven PVDF-HFP having a thickness to produce 13μm by electrospinning method, sandwiched between E2 Like the actuator, stacking actuator performs compression under conditions of room temperature, 0.1 N / ^mm 2, 3 minutes I got F. The thickness of the laminated actuator F was 346 μm.

Further, a laminating member made of a non-woven fabric of PVDF-HFP having a film thickness of 13 μm produced by an electric field spinning method is sandwiched between the two laminated actuators F, and crimped under the conditions of ^{room temperature, 0.1 N / mm for 2 to 3 minutes.} A laminated actuator G was obtained. The thickness of the laminated actuator G was 725 μm. The number of laminated actuators G is 4.

The amount of deformation of the actuator when each of the actuator E and the laminated actuators F and G is attached to the electrode jig and a rectangular wave voltage having a frequency of 0.01 Hz and ± 2 V is applied between the electrode jigs is 5 mm from the electrode jig. The position was irradiated with a laser, and the measurement was performed using a laser displacement meter (LC2100 manufactured by Keyence Co., Ltd.).

FIG. 4 shows the relationship between the number of stacked actuators and the amount of displacement obtained from the above measurement. As described above, it is ideal that the same amount of deformation as a single actuator can be obtained even when a plurality of actuators are stacked. As shown in FIG. 4, the amount of deformation when the number of layers is 2 is 83% of the amount when the number of layers is 1, and it can be seen that the decrease in the amount of deformation due to the layers is small. Further, even when the number of layers is 4, the amount of deformation is 78% of the case where the number of layers is 1, and the decrease in the amount of deformation due to the layers is limited.

FIG. 5 shows the relationship between the number of stacked actuators and the shrinkage rate calculated by the formula shown in FIG.

The shrinkage rate indicates how much the electrode film shrinks when a voltage is applied. Since this equation holds for a single actuator, the contraction rate of the laminated actuator calculated from this equation is an apparent value. From FIG. 5, it can be seen that the apparent shrinkage rate increases as the number of layers increases. On the other hand, when a single actuator is simply thickened, the expansion / contraction rate tends to be smaller than that of an actuator having a small thickness due to problems of charging speed and ion transfer speed due to resistance of the electrode portion. Therefore, assuming that the expansion / contraction ratio is equal to or less than that of the equation shown in FIG. 3, in the case of a single actuator, the thicker the actuator, the smaller the amount of deformation. From this, it can be seen that by stacking the actuators, a deformation amount that cannot be realized by a single actuator having the same thickness is obtained.

Further, for each of the actuator E and the laminated actuators F and G, the generated force was measured using a load cell (LTS-50GA manufactured by Kyowa Electric Co., Ltd.). The measurement point is at a position 4 mm from the fixed end.

FIG. 6 shows the relationship between the number of stacked actuators and the generated force obtained from the above measurement. It can be seen that the larger the number of layers, the larger the generated force, and the effect of the layers is obtained.

Claims (6)

A laminated actuator having a plurality of polymer actuator unit and one or more insulating materials, the insulating material is sandwiched between the polymer actuator unit, wherein the insulating material is composed of a nonwoven fabric of organic polymer fibers, said A laminated actuator having a structure in which a polymer actuator unit sandwiches an electrolyte layer between two electrode layers. The laminated actuator according to claim 1, wherein the organic polymer fiber has an average diameter of less than 1000 nm. The laminated actuator according to claim 1 or 2, wherein the organic polymer is a fluoropolymer. The laminated actuator according to any one of claims 1 to 3, wherein the polymer actuator unit contains nanocarbon. The laminated actuator according to any one of claims 1 to 4, wherein the organic polymer is a copolymer of a fluorinated olefin having a hydrogen atom and a per-fluorinated olefin. The laminated actuator according to any one of claims 1 to 5, wherein the nonwoven fabric is an electrospun nonwoven fabric.

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