KR20220023206A - Tactile actuator based on ionic polymer-inorganic particle complex and method for manufacturing same - Google Patents

Abstract

The present invention discloses a tactile actuator. The tactile actuator according to an embodiment of the present invention includes a lower electrode, an upper electrode, and an active layer disposed between the lower electrode and the upper electrode, wherein the active layer includes inorganic particles having a surface ion layer and an ionic polymer composite in which the inorganic particles are dispersed, the surface ion layer has a first ion and a second ion, the first ion is hydrogen-bonded on the surface of the inorganic particles, and the second ions are coupled to the first ions by electrostatic attraction to form the surface ion layer. An embodiment of the present invention is to provide a low-power ionic actuator device that can be driven at a low voltage using an ionic polymer material as an active layer.

Description

Tactile actuator based on ionic polymer-inorganic particle complex and manufacturing method thereof

The present invention relates to an actuator, and more particularly, to a tactile actuator with increased ion transfer characteristics according to an electrical signal applied through an ionic polymer-inorganic particle complex.

With the recent development of wearable electronic devices and robot technology, in the IoT-based augmented reality/virtual reality field and emerging fields such as soft robotics and biopharmaceuticals, mechanical stimulation is provided to users through various driving characteristics and applied to miniaturized devices. Therefore, the demand for low voltage driven electromechanical converters is increasing. A promising candidate for this is an ionic polymer actuator capable of large displacement under a low operating voltage of only a few volts. The unique salient features of ionic polymer actuators include flexibility, ease of manufacture, low cost and light weight. Extensive efforts have been made to improve the performance of ionic polymer actuators over the past decade through the discovery of novel ionic polymers, and various electrode materials, especially ionic liquids, have demonstrated the advantages of a wide range of electrochemical stability and high ionic conductivity. Because it provides, the introduction of ionic liquids into actuators is showing great potential to achieve large bending strains with long cycle life.

In the case of research related to artificial actuators with high driving force characteristics for realization of tactile feedback, an ionic material and a metallic material are mixed to ensure high mechanical properties and low driving voltage in the active layer. When voltage is applied by forming electrodes on both sides of the ionic polymer-metal complex, actuator characteristics are shown through the difference in concentration and size of ions accumulated at the interface of both electrodes, and high driving force characteristics due to high mechanical properties through the contained metal material. is implemented

Due to the high mechanical properties of the metal material to ensure high driving force characteristics, i) it is difficult to secure a high operating displacement of the actuator, and due to the decrease in the intrinsic ion mobility of the ionic material contained in the polymer ii) the user with a low driving frequency It is difficult to provide various tactile stimuli to users, and iii) there is a technical limit in which it is difficult to secure sufficient driving force to provide actual tactile feedback due to the slow operation response speed by electrical signals. It is a required time.

Korean Patent Publication No. 10-1213246, "Motor driving device and driving method using actuator of ionic polymer-metal composite material" Korean Patent Application Laid-Open No. 10-2015-0034537, "Electroactive polymer matrix and electroactive polymer matrix system comprising same"

An embodiment of the present invention is to provide a low-power ionic actuator device that can be driven at a low voltage using an ionic polymer material as an active layer.

In addition, an embodiment of the present invention is to provide an ionic actuator device using a mechanism for improving ion transport characteristics based on inorganic particles bonded to ions on the surface of the low-power ionic actuator device.

In addition, an embodiment of the present invention is to provide a tactile actuator having an ionic actuator element with improved high driving frequency and high driving force characteristics at the same time using the above mechanism.

The tactile actuator according to the present invention includes a lower electrode and an upper electrode, and an active layer disposed between the lower electrode and the upper electrode, wherein the active layer includes inorganic particles having a surface ionic layer and an ionic polymer in which the inorganic particles are dispersed. comprising a complex, wherein the surface ion layer has first ions and second ions, the first ions are hydrogen-bonded on the surface of the inorganic particles, and the second ions are electrostatically coupled to the first ions It is characterized in that the surface ion layer is formed.

The ionic polymer composite of the tactile actuator according to an embodiment of the present invention is composed of a polymer and an ionic material, and the ionic material is 20 to 60% by weight based on 100% by weight of the total of the elastic polymer and the ionic material characterized.

The second ion of the tactile actuator according to an embodiment of the present invention is characterized in that when an electrical signal is applied to the lower electrode and the upper electrode, the second ion is dissociated and combined with another adjacent first ion.

The inorganic particles of the tactile actuator according to an embodiment of the present invention are characterized in that silica, alumina, zirconia, or titania.

The first ion of the tactile actuator according to an embodiment of the present invention is an anion, and the anion is carboxylate or carbonate. phosphate, sulfonate, sulfate, cyanate, imide, bis(sulfonyl)imide, dicyanamide, It is characterized in that at least one anion selected from the group consisting of hexafluoroantimonate, hydroxide, nitrite, and tetrafluoroborate.

The anion of the tactile actuator according to an embodiment of the present invention is bis(sulfonyl)imide represented by the following Chemical Formula 1.

[Formula 1]

In Formula 1, R1 and R2 independently represent fluorine or a fluorinated alkyl group having 1 to 4 carbon atoms.

The second ion of the tactile actuator according to an embodiment of the present invention is a cation, and the cation is ammonium, choline, imidazolium, phosphonium, pyridinium, It is characterized in that at least one cation selected from the group consisting of pyrazolium, pyrrolidinium, piperidinium, morpholinium, and sulfonium.

The ionic material of the tactile actuator according to an embodiment of the present invention comprises an anion that is a bis(perfluoroalkylsulfonyl)imide having a perfluoroalkyl group having 1 to 4 carbon atoms, and a cation that is imidazolium. do it with

The method for manufacturing a tactile actuator according to the present invention comprises the steps of preparing a polymer solution by mixing a polymer and a solvent, preparing inorganic particles having a surface ionic layer by mixing inorganic particles and an ionic material, inorganic particles having the surface ionic layer and Comprising the steps of preparing an active layer by mixing and then thermosetting the polymer solution, and forming an upper electrode and a lower electrode on both surfaces of the active layer, the surface ion layer has a first ion and an electrostatic attraction between the first ion and the first ion It is characterized in that it consists of second ions bound to

The ionic material of the tactile actuator manufacturing method according to the embodiment of the present invention is characterized in that 20 to 60% by weight based on 100% by weight of the total of the elastic polymer and the ionic material.

The step of forming the electrodes on both sides of the active layer of the method for manufacturing a tactile actuator according to an embodiment of the present invention is characterized in that the electrode is formed by a transfer or spray coating method.

Since the embodiment of the present invention uses an ionic polymer material as an active layer, it is possible to provide a low-power ionic actuator device that can be driven at a low voltage of less than 3V.

An embodiment of the present invention provides a tactile sense having an ionic actuator element with improved high driving frequency and high driving force characteristics at the same time by using a mechanism for improving ion transport characteristics based on inorganic particles bonded to ions on the surface of the low-power ionic actuator element. An actuator may be provided.

1 is a cross-sectional view of a tactile actuator according to an embodiment of the present invention.
2 is a more detailed cross-sectional view of a tactile actuator according to an embodiment of the present invention.
3 is a schematic diagram of a driving mechanism of a tactile actuator according to an embodiment of the present invention.
4 is a schematic diagram of a method for manufacturing a tactile actuator according to an embodiment of the present invention.
5 is a graph showing activation energy of an active layer of a tactile actuator according to Examples 1 and 2 and Comparative Examples 1 and 2 of the present invention.
6 is a graph showing the results of measuring the driving displacement and driving force of the tactile actuator according to the embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings and contents described in the accompanying drawings, but the present invention is not limited or limited by the embodiments.

The terminology used herein is for the purpose of describing the embodiments and is not intended to limit the present invention. In this specification, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, "comprises" and/or "comprising" does not exclude the presence or addition of one or more other elements, steps, or elements mentioned.

As used herein, “embodiment”, “example”, “aspect”, “exemplary”, etc. are to be construed as advantageous in any aspect or design described as being preferred or advantageous over other aspects or designs. is not doing

Also, the term 'or' means 'inclusive or' rather than 'exclusive or'. That is, unless stated otherwise or clear from context, the expression 'x employs a or b' means any of natural inclusive permutations.

Also, as used herein and in the claims, the singular expression "a" or "an" generally means "one or more," unless stated otherwise or clear from the context that it relates to the singular form. should be interpreted as

The terms used in the description below have been selected as general and universal in the related technical field, but there may be other terms depending on the development and/or change of technology, customs, preferences of technicians, and the like. Therefore, the terms used in the description below should not be construed as limiting the technical idea, but as illustrative terms for describing the embodiments.

In addition, in a specific case, there is a term arbitrarily selected by the applicant, and in this case, the meaning will be described in detail in the corresponding description. Therefore, the terms used in the description below should be understood based on the meaning of the term and the content throughout the specification, rather than the simple name of the term.

Unless otherwise defined, all terms (including technical and scientific terms) used herein may be used with the meaning commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in a commonly used dictionary are not to be interpreted ideally or excessively unless clearly defined in particular.

Meanwhile, in the description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. In addition, the terms used in this specification are terms used to properly express the embodiment of the present invention, which may vary according to the intention of a user or operator or customs in the field to which the present invention belongs. Accordingly, definitions of these terms should be made based on the content throughout this specification.

Hereinafter, a description of the tactile actuator 100 using the ionic polymer-inorganic particle complex according to an embodiment of the present invention is as follows, and a cross-sectional view of the tactile actuator 100 is shown in FIG. 1 .

1, the tactile actuator 100 according to the embodiment of the present invention includes a lower electrode 110 and an upper electrode 120 and an active layer disposed between the lower electrode 110 and the upper electrode 120 ( 130), and the active layer 130 includes the inorganic particles 150 having the surface ionic layer 170 and the ionic polymer composite 180 in which the inorganic particles 150 are dispersed.

The surface ion layer 170 includes first ions and second ions, the first ions are hydrogen-bonded on the surface of the inorganic particles 150, and the second ions are electrostatically attracted to the first ions. It is characterized in that it is combined to form the surface ion layer (170).

2 is a cross-sectional view showing the tactile actuator 100 according to the embodiment of the present invention in more detail.

Referring to FIG. 2 , a tactile actuator 100 according to an embodiment of the present invention includes a lower electrode 110 and an upper electrode 120 , and an active layer 130 disposed between the lower electrode 110 and the upper electrode 120 . ) has been described in more detail.

In this case, the lower electrode 110 and the upper electrode 110 may be a metal layer, a conductive metal oxide layer, a conductive carbon layer, a metal nanowire network layer, a graphene layer, a graphite layer, or a conductive polymer layer regardless of each other, and a conductive material If so, there is no limit.

An upper substrate (not shown) may be disposed on the upper electrode 21 , and a lower substrate (not shown) may be disposed under the lower electrode 11 . These substrates may serve as a support, and may be a glass substrate or a polymer substrate. When the substrate is a flexible substrate such as a polymer substrate and the electrodes 110 and 120 are flexible electrodes, the tactile actuator 100 may be disposed on the surface of an object.

The active layer 130 includes inorganic particles having the surface ion layer 170 dispersed in the ionic polymer composite 180 .

The ionic polymer complex 180 includes an ionic material 160 having a cation and an anion, and contains a polymer 140 , and the polymer 140 is an elastic polymer. In addition, the elastic polymer may impart viscoelasticity to the active layer 130 .

The polymer 140 may be polyisoprene, polybutadiene, polyisobutylene, or polyurethane. Preferably, the polymer 140 is a thermoplastic block copolymer of the hard segment 144 and the soft segment 142 . It may be an elastic polymer. The thermoplastic elastomer (TPE) may be polystyrene-based, polyolefin-based, polyester-based, polyurethane-based, or polyamide-based TPE, which are classified according to the type of hard segment. As an example, polystyrene-based TPE, that is, thermoplastic polystyrene, is styrene-butadiene-styrene (SBS), styrene-polyisoprene-styrene (SIS) in which the hard segment is polystyrene and the soft segment is polybutadiene, polyisoprene, and polyethylene/polybutylene (SIS). , or styrene-polyethylene/polybutyrene-styrene (SEBS). In the polyester system, the hard segment may be an aromatic polyester and the soft segment may be an aliphatic polyether or aliphatic polyester. In the polyurethane-based TPE, the hard segment may be an aromatic polyurethane, and the soft segment may be an aliphatic polyether or aliphatic polyester. In the polyamide-based TPE, the hard segment may be an aromatic polyamide, and the soft segment may be an aliphatic polyether or aliphatic polyester. Among the thermoplastic elastic polymers, a polyester-based, polyurethane-based, or polyamide-based TPE having a functional group capable of hydrogen bonding to the soft segment may be used.

The inorganic particles 150 may be inorganic particles 150 having a surface functional group (SFG), for example, a hydroxyl group on the surface. In this case, a portion of the polymer 140 may interact with the surface functional group (SFG) of the inorganic particle 150, for example, may be bonded by hydrogen bonding.

When the polymer 140 is a thermoplastic elastic polymer that is a block copolymer of the hard segment 144 and the soft segment 142 , the hydroxyl group as a functional group (SFG) on the surface of the inorganic particle 150 is the soft segment 142 . ) can be hydrogen-bonded. Accordingly, the inorganic particles 150 may be attached to the polymer 140 . In addition, the inorganic particles 150 may be almost uniformly dispersed in the ionic polymer composite 180 .

The inorganic particles 150 may have a network having an M-O-M bond as a main skeleton, and may be, for example, silica, titania, alumina, or zirconia. The inorganic particles 150 may have porosity, and in this case, a hydroxyl group may be located on the surface in the pores of the porous inorganic particles. The inorganic particles 150 may have a diameter of micrometers, for example, about several to several tens of μm, specifically about 1 to 20 μm, and more specifically about 5 to 10 μm.

이하 구체적으로 상온에서 액체 상태로 유동성을 갖는 물질을 의미할 수 있다. The ionic material 160 is a salt in which a cation 164 and an anion 162 are combined by an ionic bond, about 100

Hereinafter, specifically, it may refer to a material having fluidity in a liquid state at room temperature.

When the surface functional group (SFG) is a hydroxyl group, the interaction may be hydrogen bonding. Specifically, any one of the cation 164 and the anion 162 has N, O, or F in the molecule, and hydrogen bonds to a hydroxyl group, which is a functional group (SFG) located on the surface of the inorganic particle 150 , It may be constrained or fixed on the surface of the inorganic particle 150 . As an example, the anion 162 of the cation 164 and the anion 162 includes N, O, or F in the molecule and is constrained on the surface of the inorganic particle 150 by hydrogen bonding, and the cation 164 ) may be bound by ionic bonds to the anions 162 by ionic bonds to form an ionic double layer, that is, the surface double layer 170 on the surface of the inorganic particles 150 .

The surface double layer 170 includes a first ion that hydrogen bonds with a functional group (SFG) on the surface of the inorganic particle 150 and a second ion that bonds with the first ion by electrostatic attraction.

The first ion is derived from the anion 162 of the ionic material 160 , and the second ion is derived from the cation 164 of the ionic material 160 .

On the other hand, some of the ionic liquid 37 that is not immobilized or constrained on the surface of the inorganic particle 150 , that is, the cations 164 and the anions 162 , are adjacent to the hard segment 144 of the polymer 140 . ) or other portions may maintain fluidity in the active layer 130 .

The amount of cations 164 and anions 162 maintaining fluidity in the active layer 130 can be adjusted by adjusting the amount of the ionic substance 160 added, and in order to maintain the fluidity, the ionic substance 160 . The silver polymer 140 and the ionic material 160 contains 20 to 60% by weight based on 100% by weight of the total. When the amount of the ionic material 160 is less than 20% by weight relative to 100% by weight of the total of the polymer 140 and the ionic material 160 , the cations 164 and the anions 162 maintaining fluidity in the active layer 130 . ) is mostly confined on the surface of the inorganic particles 150 , or the amount of ions disposed between the hard segments 144 to maintain fluidity in the active layer 130 is present in a very small amount. In this case, there is a limitation in effective implementation of the mechanism because the number of ions having fluidity in the active layer is small, and the flexibility of the active layer is too insufficient to operate as a tactile actuator. When the amount of the ionic material 160 is greater than 60% by weight relative to 100% by weight, it is difficult to operate as a high tactile actuator due to the actuator operation by ions having fluidity rather than the transfer effect of constrained ions to implement the mechanism.

The anion 162 may be an anion having N, O, or F in the molecule, and the anion having N, O, or F in the molecule is carboxylate or carbonate. phosphate, sulfonate, sulfate, cyanate, imide, bis(sulfonyl)imide, dicyanamide, It may be at least one anion selected from the group consisting of hexafluoroantimonate, hydroxide, nitrite, and tetrafluoroborate. Furthermore, the anion may be a fluorinated anion containing fluorine in its molecule.

The carboxylate anion may be acetate, aminoacetate, benzoate, lactate, thiosalicylate, or trifluoroacetate, and the carbonate anion Silver may be hydrogen carbonate or methyl carbonate, the phosphate anion may be dibutyl phosphate or hexafluorophosphate, and the sulfonate anion may be heptadecafluoro It may be rooctanesulfonate (heptadecafluorooctanesulfonate), methanesulfonate (methanesulfonate), nonafluorobutanesulfonate (nonafluorobutanesulfonate), trifluoromethanesulfonate (trifluoromethanesulfonate), or tosylate (tosylate), wherein the sulfate anion is a hydride hydrogen sulfate, 2-(2-methoxyethoxy)ethyl sulfate, methyl sulfate, or octyl sulfate, wherein The cyanate anion may be thiocyanate, and the imide anion may be succinimide. The bis(sulfonyl)imide may be represented by Formula 1 below.

[Formula 1]

In Formula 1, R1 and R2 may be fluorine or a fluorinated alkyl group having 1 to 4 carbon atoms, regardless of each other. The fluorinated alkyl group may be a perfluorinated alkyl group.

The bis(sulfonyl)imide is a bis(perfluoroalkylsulfonyl)imide having a perfluoroalkyl group having 1 to 4 carbon atoms, for example, bis(fluoromethylsulfonyl)imide , FSI), bis(trifluoromethylsulfonyl)imide (TFSI), bis(perfluoroethylsulfonyl)imide (bis(pentafluoroethylsulfonyl)imide, BETI), or (perfluoro robutylsulfonyl)(trifluoromethylsulfonyl)imide ((nonafluorobutylsulfonyl) (trifluoromethylsulfonyl) imide, IM14).

The cation of the ionic material 160 is ammonium (ammonium), choline (choline), imidazolium (imidazolium), phosphonium (phosphonium), pyridinium (pyridinium), pyrazolium (pyrazolium), pyrrolidinium (pyrrolidinium) ), piperidinium, morpholinium, and sulfonium may be at least one cation selected from the group consisting of. When the cation is imidazolium, pyridinium, pyrazolium, etc. having a pi bond in the molecule, there may be a binding force between the cations due to a pi-pi bond.

The ammonium is a quaternary ammonium having 4 of the alkyl groups having 1 to 20 carbon atoms regardless of each other, for example, butyltrimethylammonium, tributylmethylammonium, triethylmethylammonium, ethyldimethylpropylammonium, 2-Hydroxyethyl-trimethylammonium, tri(2-hydroxyethyl)methylammonium, methyltrioctadecylammonium, methyltrioctylammonium, tetramethylammonium, tetraethylammonium, tetrabutylammonium, tetrapentylammonium, tetrahexyl ammonium, tetraheptylammonium, tetraoctylammonium, tetradecylammonium, tetradodecylammonium, or tetrahexadecylammonium.

The imidazolium is 1-allyl-3-methylimidazolium, 1-benzyl-3-methylimidazolium, 1,3-bis(cyanomethyl)imidazolium, 1,3-bis(cyanopropyl ) imidazolium, 1-butyl-2,3-dimethylimidazolium, 1-butyl-3-methylimidazolium, 1-butyl-3- (3,3,4,4,5,5,6 ,6,7,7,8,8,8-tridecafluorooctyl)imidazolium, 1-(3-cyanopropyl)-3-methylimidazolium, 1-decyl-3-methylimidazolium , 1,3-diethoxyimidazolium, 1,3-dimethoxyimidazolium, 1,3-dihydroxyimidazolium, 1,3-dihydroxy-2-methoxyimidazolium, 1,3-dimethoxy-2-methylimidazolium, 1,3-dimethylimidazolium, 1,2-dimethyl-3-propylimidazolium, 1-dodecyl-3-methylimidazolium , 1-ethyl-2,3-dimethylimidazolium, 1-ethyl-3-methylimidazolium, 1-hexyl-3-methylimidazolium, 1-(2-hydroxyethyl)-3-methyl Imidazolium, 1-methylimidazolium, 1-methyl-3-octylimimi

Dazolium, 1-methyl-3-propylimidazolium, 1-methyl-3-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro rooctyl)imidazolium, 1-methyl-3-vinylimidazolium, or 1,2,3-trimethylimidazolium.

The phosphonium may be tetrabutylphosphonium, tributylmethylphosphonium, triethylmethylphosphonium, or trihexyltetradecylphosphonium. The pyridinium is 1-butyl-3-methylpyridinium, 1-butyl-4-methylpyridinium, 1-butylpyridinium, 1-(3-cyanopropyl)pyridinium, 1-ethylpyridinium, or 3 -methyl-1-propylpyridinium. The pyrrolidinium may be 1-butyl-1-methylpyrrolidinium or 1-ethyl-1-methylpyrrolidinium. The pyrazolium may be 1,2,4-trimethylpyrazolium. The sulfonium may be triethylsulfonium. The piperidinium may be 1-butyl-1-methylpiperidinium or 1-ethyl-1-methylpiperidinium. The morpholinium may be 4-ethyl-4-methylmorpholinium. Specifically, the ionic material 160 may be 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM]+[TFSI]−) which is an ionic liquid (IL).

3 is a schematic diagram of an operation mechanism of a tactile actuator according to an embodiment of the present invention.

Referring to FIG. 3 and referring again to FIG. 2 , a voltage may be applied to the electrodes 110 and 120 of the tactile actuator, and the tactile actuator may operate while the voltage is applied.

When a voltage is applied to the electrodes 110 and 120, the polymer 140 is not constrained on the surface of the inorganic particle 150 among the anions 162 and the cations 164 present in the active layer 130, and Anions 162 and cations 164 having fluidity that are not disposed between the adjacent hard segments 144 are drawn onto the surfaces of the electrodes 110 and 120 to form an electrostatic double layer, resulting in the accumulation of ions. show driving characteristics.

The surface ion layer of the inorganic particle 150 includes first ions and second ions, and the second ions coupled to the surface ion layer by electrostatic attraction with the first ions. The second ions are the lower electrode 110 . ) and the upper electrode 120 may be combined with other adjacent first ions while dissociating and moving when an electrical signal is applied.

At this time, the first ion bonded to the surface of the inorganic particle 150 is used as an ion transfer point, and another second ion dissociated by an electrical signal recombines with another first ion bonded to the surface of the inorganic particle 150 . And, by replacing the other second ions that were previously bound, the ion transport properties of the moving second ions are improved.

A method of manufacturing a tactile actuator according to another embodiment of the present invention will be described below.

The tactile actuator manufacturing method includes the steps of preparing a polymer solution by mixing a polymer and a solvent, preparing inorganic particles having a surface ion layer by mixing inorganic particles and an ionic material, inorganic particles having the surface ion layer and the polymer solution Comprising the steps of preparing an active layer by thermal curing after mixing and forming an upper electrode and a lower electrode on both surfaces of the active layer, wherein the surface ion layer has a first ion and a second ion, and the first ion is hydrogen-bonded on the surface of the inorganic particle, and the second ion is coupled to the first ion by electrostatic attraction to form the surface ion layer.

The polymer is the same as the polymer material described with reference to FIG. 2, and the solvent may be distilled water or water including purified water.

The inorganic particles are derived from a metal oxide precursor, and the metal oxide precursor includes a hydroxyl group, an alkoxy group having 1, 2 or 3 carbon atoms, a halo group, or two or more of them. It may be silicon, titanium, aluminum, or zirconium with functional groups corresponding to the combination.

As an example, the metal oxide precursor may be a silicon alkoxide, a titanium(IV) alkoxide, an aluminum alkoxide, or a zirconium(IV) alkoxide. Specifically, the metal oxide precursor may be Tetraethylorthosilicate (TEOS). In addition, the metal oxide precursor may be provided in the form of an aqueous solution, and may have an almost neutral pH. The ionic material has a cation and an anion as described with reference to FIG. 2 and may have a liquid form at 100 degrees or less.

In the step of preparing the inorganic particles having the surface ionic layer, a sol-gel reaction may occur in the mixed solution of the inorganic particles and the ionic material to generate inorganic particles having the surface ionic layer. For this purpose, a catalyst may be added to the mixed solution, and the catalyst is an acid catalyst, and specifically, hydrochloric acid or an aqueous hydrochloric acid solution may be added. In this case, the ionic material includes a cation and an anion.

The inorganic particles may be micro particles having a network structure formed of M-O-M bonds. In the sol-gel reaction, hydrolysis of inorganic particles and a condensation reaction between the hydrolyzed inorganic particles occur thereafter. The porosity of the inorganic particles having the surface ion layer can be reduced.

In this embodiment, in order to increase the hydrolysis rate compared to the condensation reaction rate, an acid catalyst and an aqueous hydrochloric acid solution capable of exhibiting strong acidity was used as the catalyst, but is not limited thereto. In some cases, the porosity of the inorganic particles may be increased by increasing the rate of the condensation reaction compared to the rate of hydrolysis.

The surface ion layer includes a first ion and a second ion bonded to the surface of the inorganic particle, the first ion is derived from an anion of the ionic material, and the second ion is derived from a cation of the ionic material do.

In addition, as the metal oxide precursor and the ionic material are mixed before proceeding with the sol-gel reaction, the cations and anions provided in the ionic material form a relatively high-density ionic double layer constrained on the surface of the inorganic particles. can As described above, the ionic double layer is an example of an ion having a functional group capable of hydrogen bonding among ionic materials. Also, a cation that is a counter ion of the anion may be formed by being bound to the anion by an ionic bond.

The ionic material may serve as a surfactant and as a plasticizer. Specifically, the ionic material can form an ionic double layer on the surface of the hydrophilic inorganic particle to modify the surface of the hydrophilic inorganic particle to be hydrophobic, and thus the inorganic particle in the active layer formed by mixing with the hydrophobic elastic polymer gel. A homogeneous dispersion can be induced.

The ionic material 160 includes 20 to 60% by weight based on 100% by weight of the polymer 140 and the ionic material 160 .

When the ionic material 160 is less than 20% by weight relative to 100% by weight of the total of the polymer 140 and the ionic material 160, the cations 164 and the anions 162 that maintain fluidity in the active layer 130 Most of these are confined on the surface of the inorganic particles 150 , or the amount of ions disposed between the hard segments 144 to maintain fluidity in the active layer 130 is present in a very small amount. In this case, there is a limitation in effective implementation of the mechanism because the number of ions having fluidity in the active layer is small, and the flexibility of the active layer is too insufficient to operate as a tactile actuator, and on the contrary, the entire polymer 140 and the ionic material 160 are When the amount of the ionic material 160 is greater than 60% by weight relative to 100% by weight, it is difficult to operate as a high tactile actuator due to the actuator operation by ions having fluidity rather than the transfer effect of constrained ions to implement the mechanism.

The step of preparing the active layer by mixing the inorganic particles having the surface ionic layer with the polymer solution and then thermosetting the polymer solution may further include mixing the inorganic particles having the surface ionic layer with the polymer solution and molding the mixture, The active layer may be in the form of a film.

Hereinafter, a preferred experimental example (example) is presented to help the understanding of the present invention. However, the following experimental examples are only for helping understanding of the present invention, and the present invention is not limited by the following experimental examples.

Example 1. ( 60 wt% Si-i-TPU material)

A polymer solution is prepared by mixing a thermoplastic elastomer (thermoplastic polyurethane (TPU)) and a solvent (N,N-Dimethylformamide (DMF)) in a 1:5 weight ratio and stirring at 80 °C for 5 hours.

에서 10 분 간 교반하여 전구체 수용액을 제조함.0.5 mL of a precursor (Tetraethyl orthosilicate (TEOS)) capable of forming silica particles through a sol-gel reaction was mixed with 0.25 mL of water and 40

Aqueous solution of precursor was prepared by stirring for 10 minutes.

= 60 중량%)인 것이다. 60% by weight of the ionic liquid (Ionic liquid (IL), 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM] + [TFSI] -)) is mixed with the aqueous precursor solution. If the mixing of the thermoplastic elastic polymer and the ionic liquid is described further including the weight unit, 100 g of the thermoplastic carbon polymer contains 150 g of the ionic liquid, and the ionic polymer (thermoplastic elastic polymer containing 150 g of the ionic liquid) Polymers and ionic liquids) solutions ( (

= 60% by weight).

에서 교반을 진행하며, 0.05 mL 의 염산수용액 (0.06M HCl)을 적하하여 동일 조건에서 2 시간 동안 교반을 진행하여 표면 이온층이 도입된 무기입자 분산용액을 제조한다. When the ionic liquid is mixed with the aqueous precursor solution, the same temperature condition (40

While stirring, 0.05 mL of an aqueous hydrochloric acid solution (0.06M HCl) is added dropwise and stirred under the same conditions for 2 hours to prepare a dispersion solution of inorganic particles having a surface ion layer introduced therein.

The prepared inorganic particle dispersion solution was added dropwise to the polymer solution in an amount of 19 wt% based on 100 wt% of the thermoplastic elastic polymer and the prepared inorganic particle dispersion solution, followed by stirring at 80 ° C. for additional 20 hours to obtain ionic polymer-inorganic particles. A composite material solution is prepared. The dripping refers to the process of slowly dropping one drop at a time.

The prepared composite material solution is poured into a Teflon dish at 40 ° C., and finally heat-treated at 80 ° C. for 72 hours through a temperature increase process of 10 ° C per hour to prepare an ionic polymer-composite material film. .

A conductive polymer solution is prepared by mixing a conductive polymer (conducting polymer, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS)) and a solvent (distilled water) in a 1:3 weight ratio, and then dispersing with a sonicator for 15 minutes. do.

A polar solvent (Dimethyl sulfoxide (DMSO)) and an ionic liquid (Ionic liquid (IL), 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM]+[TFSI]-)) The conductive polymer solution and the ionic liquid were sequentially mixed in the solvent to contain 0.05 parts by weight and 0.015 parts by weight, respectively, and stirred at room temperature for 3 hours to prepare an ionic-conductive polymer solution. That is, the preparation ratio of the conductive polymer solution is prepared by mixing conductive polymer (PEDOT:PSS): solvent (distilled water): polar solvent (DMSO): ionic liquid = 1: 3: 0.05: 0.015 by weight.

The prepared ionic-conductive polymer solution is dispersed through a sonicator for 15 minutes, and the ionic-conductive polymer solution is uniformly spray coated on both sides of the prepared ionic polymer-composite film at 100 ° C. A tactile actuator is manufactured by forming the upper and lower electrodes with this method and performing heat treatment at 120 °C for 30 minutes.

At this time, in the case of the ionic liquid, since the boiling point is 190.5 ° C and the vapor pressure has a very low vapor pressure of 10-8 Pa at room temperature (25 ° C), the evaporation of the ionic liquid during the heat treatment process Since no loss occurs, the ionic liquid in the final material is present in the tactile actuator without loss.

Example 2. ( 20 wt% Si-i-TPU material)

In the same manner as in Example 1, but in the step of preparing the inorganic particle dispersion solution, 20% by weight of the ionic liquid (IL), 1-Ethyl-, based on the weight of the thermoplastic elastic polymer in the polymer solution This is performed using 3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM]+[TFSI]-)).

Example 3. ( 60 wt% i-TPU material)

에서 5 시간 교반하여 고분자 용액을 제조한다. Mix the thermoplastic elastomer (thermoplastic polyurethane (TPU)) and the solvent (N,N-Dimethylformamide (DMF)) in a 1:4 weight ratio and 80

A polymer solution is prepared by stirring for 5 hours.

60% by weight of the ionic liquid (Ionic liquid (IL), 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM] + [TFSI] -)) is mixed and stirred for an additional 20 hours to prepare an ionic polymer solution.

= 60 중량%)인 것이다. If the mixing of the thermoplastic elastic polymer and the ionic liquid is described further including the weight unit, 100 g of the thermoplastic carbon polymer contains 150 g of the ionic liquid, and the ionic polymer (thermoplastic elastic polymer containing 150 g of the ionic liquid) Polymers and ionic liquids) solutions ( (

= 60% by weight).

의 테프론 용기 (Teflon dish)에 붓고 시간당 10

의 승온 과정을 통해 최종적으로 120

에서 48 시간 동안 열처리를 진행하여 이온성 고분자 소재 필름을 제조하여 준비한다. The prepared composite material solution was

Pour into a Teflon dish of 10 per hour

Finally through the process of raising the temperature of 120

Heat treatment for 48 hours to prepare an ionic polymer material film.

A conductive polymer solution was prepared by mixing a conductive polymer (conducting polymer, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS)) and a solvent (distilled water) in a 1:3 weight ratio, and then dispersing with a sonicator for 15 minutes. do.

A polar solvent (Dimethyl sulfoxide (DMSO)) and an ionic liquid (Ionic liquid (IL), 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM]+[TFSI]-)) The conductive polymer solution and the ionic liquid were sequentially mixed in the solvent to contain 0.05 parts by weight and 0.015 parts by weight, respectively, and stirred at room temperature for 3 hours to prepare an ionic-conductive polymer solution. That is, the preparation ratio of the conductive polymer solution is prepared by mixing conductive polymer (PEDOT:PSS): solvent (distilled water): polar solvent (DMSO): ionic liquid = 1: 3: 0.05: 0.015 by weight.

에서 스프레이 코팅 방식으로 상부 및 하부 전극을 형성하고 120

에서 30 분 간 열처리를 진행하여 촉각 액츄에이터를 제조한다. The prepared ionic-conductive polymer solution was dispersed through a sonicator for 15 minutes, and the ionic-conductive polymer solution was uniformly 100 on both sides of the prepared ionic polymer-composite film.

Forming the upper and lower electrodes by spray coating in 120

A tactile actuator is manufactured by heat treatment for 30 minutes in

Example 4. ( 20 wt% i-TPU material)

Performed in the same manner as in Comparative Example 1, but in the step of preparing the ionic polymer solution, an ionic liquid (IL), 1-Ethyl in a weight ratio of 20 wt% based on the weight of the thermoplastic elastic polymer in the polymer solution This is performed using -3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM]+[TFSI]-)).

Characteristic evaluation 1.

The activation energy of the ionic polymer-inorganic particle composite active layer prepared according to Examples 1 and 4 was measured by impedance spectroscopy, Electrochemical Impedance Spectroscopy, EIS), and the measured impedance was measured as a sample The ionic conductivity obtained by calculating the size and thickness of was analyzed according to temperature.

The analysis results are shown in Table 1 and FIG. 5 below.

Referring to FIG. 5, the result of improved ion transport properties through lower activation energy in the ionic polymer-inorganic particles introduced with inorganic particles as in Examples 1 and 2 can be confirmed.

active layer active energy Example 4
(20 wt% i-TPU) 21.78 kJ mol ^-1 Example 2
(20 wt% Si-i-TPU) 17.76 kJ mol ^-1 Example 3
(60 wt% i-TPU) 13.10 kJ mol ^-1 Example 1 (60 wt% Si-i-TPU) 12.53 kJ mol ^-1

Characteristic evaluation 2.

The driving displacement and driving force of the tactile actuators manufactured according to Example 1 and Comparative Example 1 were checked to measure their performance as an actuator. In the case of actuator performance measurement, the movement (displacement) of the actuator element was measured through the reflection of laser light. force), and the force generated at this time (blocking force, driving force) was measured.

The measurement results are shown in Table 2 and FIG. 6 below.

Referring to Table 2 below and FIG. 6 , the tactile actuator based on the ionic polymer-inorganic particle composite of Example 1 has high driving frequency and blocking force, and it can be seen that up to 100 Hz It is possible to secure various driving force characteristics from 0.05 to 0.96 mN. However, considering that the driving force that can be sensed by the user is 0.4 mN or more, Example 3 has a driving force characteristic of 0.4 mN or more only at frequencies of 0.1 to 0.5, whereas in the case of Example 1, various driving forces up to 0.1 to 5 Hz It can be seen that it has a driving force characteristic of 0.4 mN or more in the frequency range.

frequency
(Hz) Example 3
(60 wt% i-TPU) Example 1
(60 wt% Si-i-TPU) drive variation
(mm) driving force
(mN) drive variation
(mm) driving force
(mN) 0.1 3.72 0.58 3.57 0.96 0.5 2.85 0.45 2.66 0.92 One 2.21 0.37 2.05 0.81 5 0.72 0.21 0.64 0.43 10 0.41 0.10 0.45 0.27 30 0.30 0.07 0.30 0.11 50 0.24 0.05 0.16 0.08 100 0.05 0.03 0.11 0.05

As described above, although the present invention has been described with reference to limited embodiments and drawings, the present invention is not limited to the above embodiments, and various modifications and variations from these descriptions are provided by those skilled in the art to which the present invention pertains. This is possible. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined by the following claims as well as the claims and equivalents.

100: tactile actuator
110: lower electrode
120: upper electrode
130: active layer
140: polymer
142: soft segment
144: hard segment
150: inorganic particles
160: ionic liquid
162: anion
164: cation
170: surface double layer
180: ionic polymer composite

Claims (11)

a lower electrode and an upper electrode; and
an active layer disposed between the lower electrode and the upper electrode; including,
The active layer is
inorganic particles having an ionic layer on the surface; and
Including an ionic polymer composite in which the inorganic particles are dispersed,
The surface ion layer has a first ion and a second ion,
The first ion is hydrogen-bonded on the surface of the inorganic particle, and the second ion is electrostatically coupled to the first ion to form the surface ion layer.
According to claim 1,
The ionic polymer composite is composed of an elastic polymer and an ionic liquid, and the ionic liquid is 20 to 60 wt% based on 100 wt% of the total amount of the elastic polymer and the ionic liquid.
According to claim 1,
The second ion is dissociated when an electrical signal is applied to the lower electrode and the upper electrode, and is combined with another adjacent first ion.
According to claim 1,
The inorganic particles are silica, alumina, zirconia, or titania.
According to claim 1,
The first ion is an anion,
The anion is carboxylate, carbonate. phosphate, sulfonate, sulfate, cyanate, imide, bis(sulfonyl)imide, dicyanamide, A tactile actuator that is at least one anion selected from the group consisting of hexafluoroantimonate, hydroxide, nitrite, and tetrafluoroborate.
6. The method of claim 5,
The anion is bis(sulfonyl)imide represented by the following formula (1).
[Formula 1]

In Formula 1, R1 and R2 independently represent fluorine or a fluorinated alkyl group having 1 to 4 carbon atoms.
According to claim 1,
The second ion is a cation,
The cation is ammonium, choline, imidazolium, phosphonium, pyridinium, pyrazolium, pyrrolidinium, piperidinium ), a tactile actuator that is at least one cation selected from the group consisting of morpholinium, and sulfonium.
3. The method of claim 2,
The ionic liquid is a tactile actuator, characterized in that it comprises an anion that is bis(perfluoroalkylsulfonyl)imide having a perfluoroalkyl group having 1 to 4 carbon atoms, and a cation that is imidazolium.
preparing a polymer solution by mixing a polymer and a solvent;
preparing inorganic particles having a surface ionic layer by mixing inorganic particles and an ionic liquid;
preparing an active layer by mixing the inorganic particles having the surface ion layer with the polymer solution and then thermally curing the mixture; and
Comprising the step of forming an upper electrode and a lower electrode on both sides of the active layer,
The surface ion layer has a first ion and a second ion,
The first ion is hydrogen-bonded on the surface of the inorganic particle, and the second ion is coupled to the first ion by electrostatic attraction to form the surface ion layer.
10. The method of claim 9,
The ionic liquid is a tactile actuator manufacturing method, characterized in that 20 to 60% by weight based on 100% by weight of the total amount of the elastic polymer and the ionic liquid.
10. The method of claim 9,
The step of forming the electrodes on both sides of the active layer is a method of manufacturing a tactile actuator, characterized in that the electrode is formed by a transfer or spray coating method.

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