JP2015188032A - polymer actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polymer actuator which is excellent in flexibility and expansion rate, capable of being driven even in a low electric field and has low bleeding properties.SOLUTION: Disclosed is a polymer actuator 1 constituted of polyurethane elastomer 3 formed of a polyurethane elastomer composition containing a polyisocyanate component, an active hydrogen component and a catalyst. The polyurethane elastomer composition contains a mono-ol compound containing one active hydrogen group in a molecule with a concentration of 0.20 to 1.00 meg/g.

Description

  The present invention relates to a polymer actuator that is excellent in flexibility and expansion ratio, can be driven even in a low electric field, and has low bleed out property.

A polymer actuator formed of a polymer material is characterized by being lighter and more flexible than an actuator formed of a material such as ceramic or metal. Because of these features, polymer actuators are used in sensors, optical switches, diaphragms, braille displays, power generation applications such as wave power generation and wind power generation, industrial and nursing robots, medical equipment, It is attracting attention as an actuator that can operate safely even if it is directly touched with the skin. There have been various materials that have been proposed as polymer actuators so far, including ion exchange membranes, conductive polymers, dielectric elastomers, polymer gels, hydrogels, and carbon nanotubes.

  However, an actuator made of an ion exchange membrane, a conductive polymer, and a hydrogel is driven by movement of water, ions, etc., and is difficult to drive in air. Thus, a polymer actuator using a dielectric elastomer that does not require such a solvent has been proposed. However, since a polymer actuator using a dielectric elastomer has a high drive voltage for deformation of about several thousand volts, further reduction of the drive voltage has been required for practical use.

  For this reason, as a new polymer material that can be driven in the air, an elastomer such as a polyurethane elastomer is used as a polyol as a material having a dielectric property or a substituent having a relatively strong dipole moment. Or a polymer actuator obtained by adding a high dielectric solvent (Patent Documents 1 to 3).

  Patent Document 1 discloses a polyurethane elastomer having a dielectric polyol or a polyol having a substituent having a relatively strong dipole moment, and applying the DC electric field to the polyurethane elastomer, A polyurethane elastomer actuator characterized by being oriented in a direction is described. However, although the flexibility is improved by optimizing the molecular weight of the material used, there is a problem in that a high dielectric constant cannot be achieved and there is a limit to low electric field driving.

  Patent Document 2 discloses a polyurethane gel-like material in which a dielectric solvent is contained in a dielectric polyurethane elastomer or a polyurethane elastomer having a substituent having a relatively strong dipole moment, and a DC electric field is applied. Thus, a fast response polyurethane gel actuator is described in which dielectric molecules or substituents are oriented in the electric field direction and the gel structure changes anisotropically. However, the use of a high dielectric solvent improves flexibility and can achieve low electric field driving to some extent, but has a problem in that the compatibility between the matrix and the plasticizer is low and bleed out occurs.

  Patent Document 3 discloses an actuator obtained by crosslinking an elastomer composition containing an elastomer having a hetero atom in the molecule and a high dielectric constant liquid compound having a hetero atom in the molecule and compatible with the elastomer, A dielectric film suitable for transducers such as sensors is described. However, the use of a high dielectric solvent improves flexibility and can achieve low electric field driving to some extent, but has a problem in that the compatibility between the matrix and the plasticizer is low and bleed out occurs.

  Accordingly, there is a need for a polymer actuator using a dielectric elastomer that is excellent in flexibility and stretch ratio, can be driven even in a low electric field, and has low bleed out properties.

JP-A-6-85339 JP-A-6-85338 JP 2010-219380 A

  The present invention solves the problems of the conventional polymer actuators as described above, is excellent in flexibility and elongation, can be driven even in a low electric field, and has a low bleed out property. An object is to provide an actuator.

  As a result of intensive studies to achieve the above object, the inventors of the present invention, in a polymer actuator composed of a polyurethane elastomer formed from a polyurethane elastomer composition containing a polyisocyanate component, an active hydrogen component and a catalyst, By using a monool compound containing one active hydrogen group in the molecule for the polyurethane elastomer composition, and defining the monool compound concentration and the gel fraction of the polyurethane elastomer within a specific range, the polyurethane elastomer composition is flexible. The present inventors have found that a polymer actuator having excellent properties and elongation ratio, capable of being driven even with a low electric field, and having low bleed out properties can be provided.

That is, the present invention is a polymer actuator composed of a polyurethane elastomer formed from a polyurethane elastomer composition containing a polyisocyanate component, an active hydrogen component and a catalyst,
The polyurethane elastomer composition contains a monool compound containing one active hydrogen group in the molecule at a concentration of 0.20 to 1.00 meq / g,
The present invention relates to a polymer actuator wherein the polyurethane elastomer has a gel fraction of 30% or more.

Furthermore, in order to implement this invention suitably,
The monool compound has at least one functional group selected from the group consisting of an n-propyl group, a cyano group and a nitro group;
The polyurethane elastomer reacts a urethane group-containing compound obtained by reacting a monool compound containing one active hydrogen group in the molecule with a polyisocyanate component, and the active hydrogen component and the polyisocyanate component. Obtained by reacting the resulting mixture with the isocyanate-terminated compound with the active hydrogen component;
It is desirable.

As another aspect of the present invention, a polyurethane elastomer containing a polyisocyanate component, an active hydrogen component containing two or more active hydrogen groups in the molecule, a monool compound containing one active hydrogen group in the molecule, and a catalyst A method for producing a polymer actuator comprising a polyurethane elastomer molded article formed from a composition,
A step of preparing a urethane group-containing compound A by reacting a monool compound containing one active hydrogen group in the molecule with a polyisocyanate component,
A step of preparing an isocyanate-terminated compound B by reacting an active hydrogen component containing two or more active hydrogen groups in the molecule with a polyisocyanate component;
A method for producing a polymer actuator comprising: mixing the compounds A and B to form a mixture; and reacting the mixture with the active hydrogen component in the presence of the catalyst to form a polyurethane elastomer molded article There is.

Furthermore, in order to implement this invention suitably,
The concentration of the monool compound is 0.20 to 1.00 meq / g;
The monool compound has at least one functional group selected from the group consisting of an n-propyl group, a cyano group and a nitro group;
It is desirable.

  The “concentration of the monool compound” used in the present specification is an equivalent (meq) of the monool compound in 1 g of the polyurethane elastomer, calculated from the charged amount of the composition when producing the polyurethane elastomer.

  According to the present invention, in a polymer actuator composed of a polyurethane elastomer formed from a polyurethane elastomer composition containing a polyisocyanate component, an active hydrogen component and a catalyst, the polyurethane elastomer composition contains one active in the molecule. By using a monol compound containing a hydrogen group and by regulating the monool compound concentration and the gel fraction of the polyurethane elastomer within a specific range, it has excellent flexibility and elongation, and even in a low electric field. It is possible to provide a polymer actuator that can be driven and has a low bleed-out property.

It is a cross-sectional schematic diagram explaining the state of the polymer actuator before and after applying a voltage to a polymer actuator.

  The operation principle of the polymer actuator will be described below with reference to FIG. The left side of FIG. 1 shows a polymer actuator 1 before applying a voltage, and electrodes 2 are formed on both surfaces of a polyurethane elastomer 3 formed into a film shape. As shown on the right side of FIG. 1, when a voltage is applied to the electrode 2, positive and negative charges are attracted to each electrode 2, and the polyurethane elastomer 3 is compressed and reduced in thickness by the Coulomb force. Stretches in the surface direction.

ε_０：真空の誘電率
ε_ｒ：ポリウレタンエラストマーの比誘電率
Ｅ：電界強度
Ｅ＝Ｖ／ｄ（Ｖ：電圧、ｄ：厚さ）
ν：ポアソン比
ν＝Ｓ_ｘｙ／Ｓ_ｚ＝Ｐ_ｘｙ／Ｐ_ｚ
Ｙ：ポリウレタンエラストマーの弾性率 As the force P generated at this time, the generated force Pz in the thickness direction and the generated force Pxy in the surface direction, and as the expansion rate S, the expansion rate Sz in the thickness direction and the expansion rate Sxy in the surface direction are as follows.

ε ₀ : dielectric constant of vacuum ε _r : relative dielectric constant of polyurethane elastomer E: electric field strength E = V / d (V: voltage, d: thickness)
ν: Poisson's ratio ν = S _xy / S _z = P _xy / P _z
Y: Elastic modulus of polyurethane elastomer

  Therefore, it can be seen from the above formula that a high electric field strength E (= V / d), a high dielectric constant and a low elastic modulus of the polyurethane elastomer are necessary to achieve a high elongation ratio S. In order to achieve the low electric field driving which is the subject of the present invention, it is necessary to reduce the driving voltage V.

  As described above, the polymer actuator of the present invention comprises a polyurethane elastomer composition (mixed solution) containing a polyisocyanate component, an active hydrogen component and a catalyst, and a monool compound containing one active hydrogen group in the molecule. It is comprised from the polyurethane elastomer obtained by making it react and harden | cure, and additives, such as a pigment, a flame retardant, and a coloring inhibitor, can also be used.

  As the isocyanate component used in the polyurethane elastomer composition of the present invention, compounds known in the field of polyurethane can be used without particular limitation. For example, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, p-phenylene Aromatic diisocyanates such as diisocyanate, m-phenylene diisocyanate, p-xylylene diisocyanate, m-xylylene diisocyanate, ethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 1,6-hexamethylene diisocyanate 1,4-cyclohexane diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, isophorone diisocyanate, nor And alicyclic diisocyanates such as bornane diisocyanate. These may be used alone or in combination of two or more. The isocyanate may be modified by urethane modification, allophanate modification, biuret modification, isocyanurate modification or the like.

  Examples of commercially available products of the above polyisocyanate component include “Cosmonate T-80”, “Cosmonate T-100” manufactured by Mitsui Chemicals, Inc., and “Lupranate T-80” manufactured by BASF IONIC Polyurethanes.

  As the active hydrogen component, polymer polyols such as polyester polyols, polyether polyols, polycarbonate polyols, polybutadiene polyols, and castor oil polyols can be suitably used. Moreover, a polyol can be used individually or in combination of 2 or more types.

  Examples of the polyester polyol include poly (ethylene adipate), poly (diethylene adipate), poly (propylene adipate), poly (tetramethylene adipate), poly (hexamethylene adipate), poly (neopentylene adipate), 3-methyl Examples include polyols composed of -1,5-pentanediol and adipic acid, and copolymers thereof, caprolactone polyols obtained by ring-opening polymerization of ε-caprolactone, and copolymers composed of a carboxylic acid component and a glycol component.

  Examples of the polyether polyol include polytetramethylene glycol, polypropylene glycol, polyethylene glycol, a copolymer of propylene oxide and ethylene oxide, polyacrylonitrile particles, and a polyol (POP) containing polystyrene particles.

  Examples of the polycarbonate polyol include poly (hexanediol carbonate) and poly (nonanediol carbonate).

  Examples of the polybutadiene polyol include butanediene polymers such as butadiene homopolymer, isoprene homopolymer, butadiene-styrene copolymer, butadiene-isoprene copolymer, butadiene-acrylonitrile copolymer, butadiene-2-ethylhexyl acrylate copolymer, and butadiene-n-octadecyl acrylate copolymer. In which the terminal is modified with a hydroxyl group.

  Examples of the castor oil-based polyol include castor oil and modified castor oil (such as castor oil modified with a polyhydric alcohol such as trimethylolpropane and pentaerythritol).

  As a commercial product of the above polyol component, “Exenol 1020”, “Exenol 2020”, “Exenol 3020”, “Exenol 3030”, “Preminol 7001”, “Preminol 7012” manufactured by Asahi Glass Co., Ltd., and Kuraray Polyol manufactured by Kuraray Co., Ltd. “P-1010”, “P-2010”, “P-3010”, “F-1010”, “F-2010”, “F-3010”, “Placcel 210” “Placcel 220” manufactured by Daicel Corporation “Placcel 230”, “Placcel 312”, “Placcel L320AL” and the like.

  In addition to the above-described high molecular weight polyol component as an active hydrogen-containing component, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, 3-methyl-1,5-pentanediol, diethylene glycol, triethylene glycol, 1,4-bis (2-hydroxyethoxy) benzene, trimethylolpropane, glycerin, 1,2,6- Hexanetriol, pentaerythritol, tetramethylolcyclohexane, methylglucoside, sorbitol, mannitol, dulcitol, sucrose, 2,2,6,6-tetrakis (hydroxymethyl) cyclohexanol, and triethanolamine Low molecular weight polyol component equal, ethylenediamine, tolylenediamine, diphenylmethane diamine, may be used low molecular weight polyamine component of diethylenetriamine. These may be used alone or in combination of two or more. Furthermore, 4,4′-methylenebis (o-chloroaniline) (MOCA), 2,6-dichloro-p-phenylenediamine, 4,4′-methylenebis (2,3-dichloroaniline), 3,5-bis ( Methylthio) -2,4-toluenediamine, 3,5-bis (methylthio) -2,6-toluenediamine, 3,5-diethyltoluene-2,4-diamine, 3,5-diethyltoluene-2,6- Diamine, trimethylene glycol-di-p-aminobenzoate, polytetramethylene oxide-di-p-aminobenzoate, 1,2-bis (2-aminophenylthio) ethane, 4,4'-diamino-3,3 ' -Diethyl-5,5'-dimethyldiphenylmethane, N, N'-di-sec-butyl-4,4'-diaminodiphenylmethane, 4,4'-diamy -3,3'-diethyldiphenylmethane, 4,4'-diamino-3,3'-diethyl-5,5'-dimethyldiphenylmethane, 4,4'-diamino-3,3'-diisopropyl-5,5'- Dimethyldiphenylmethane, 4,4′-diamino-3,3 ′, 5,5′-tetraethyldiphenylmethane, 4,4′-diamino-3,3 ′, 5,5′-tetraisopropyldiphenylmethane, m-xylylenediamine, Polyamines exemplified by N, N′-di-sec-butyl-p-phenylenediamine, m-phenylenediamine, p-xylylenediamine and the like can also be mixed.

  Monool compounds containing one active hydrogen group in the molecule include aliphatics such as methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, pentyl alcohol, hexyl alcohol, heptyl alcohol, octyl alcohol, nonyl alcohol, and decyl alcohol. Monools; cycloaliphatic monools such as cyclohexanol and methyl-cyclohexanol; aromatic monools such as benzyl alcohol; ether-based monools such as ethylene glycol monomethyl ether and propylene glycol monomethyl ether; hydroxyacetic acid esters And ester monools such as hydroxypropionic acid esters. Among these, monool compounds having at least one functional group selected from the group consisting of an n-propyl group, a cyano group, and a nitro group are preferable. A monool compound having at least one functional group selected from the group consisting of a cyano group and a nitro group is more preferable.

  Specific examples of the monool compound include ethyl alcohol, n-propyl alcohol, isopropyl alcohol, butyl alcohol, ethylene cyanohydrin (2-cyanoethyl alcohol), 2-hydroxybutyronitrile, 2-hydroxyisobutyronitrile, and 3-hydroxy. Butyronitrile, 3-hydroxyglutaronitrile, 3-hydroxy-3-phenylpropionitrile, o-cyanobenzyl alcohol, m-cyanobenzyl alcohol, p-cyanobenzyl alcohol, 4- (2-hydroxyethyl) benzonitrile, 2-nitroethanol, 2-methyl-2-nitro-1-propanol, 3-nitro-2-butanol, 3-nitro-2-pentanol, o-nitrobenzyl alcohol, m-nitrobenzyl alcohol, p-ni Robenzyl alcohol, 2-methyl-3-nitrobenzyl alcohol, 3-methyl-2-nitrobenzyl alcohol, 3-methyl-4-nitrobenzyl alcohol, 4-methyl-3-nitrobenzyl alcohol, 5-methyl-2- Nitrobenzyl alcohol, 3-methoxy-4-nitrobenzyl alcohol, 4,5-dimethoxy-2-nitrobenzyl alcohol, 4-methoxy-3-nitrobenzyl alcohol, 5-hydroxy-2-nitrobenzyl alcohol, 4-hydroxy- Examples include 3-nitrobenzyl alcohol, 2- (4-nitrophenyl) ethanol, and n-propyl alcohol, ethylene cyanohydrin, 2-nitroethanol, and m-nitrobenzyl alcohol are preferable.

  The concentration of the monool compound is 0.20 to 1.00 meq / g, preferably 0.25 to 0.95 meq / g, more preferably 0.25 to 0, based on the total amount of the polyurethane elastomer composition. .90 meq / g. When the concentration of the monool compound is less than 0.20 meq / g, the effect of reducing the elastic modulus is small, and when it exceeds 1.00 meq / g, an increase in molecular weight is suppressed, so that a cured body (molded product) is obtained. Disappear.

  The monool compound has a molecular weight (Mn) of 30 to 300, preferably 40 to 250. When the molecular weight of the monool compound is less than 30, it is difficult to obtain a cured product (molded product) with the polyisocyanate component, and when it exceeds 300, the effect of improving the dielectric constant becomes small.

  As described above, the activity of containing a polyisocyanate component and two or more active hydrogen groups by using a monool compound containing one active hydrogen group involved in the reaction with the isocyanate component in the molecule to the polyurethane elastomer. In the curing reaction with the hydrogen component, it is possible to suppress the increase in the molecular weight of the molecular chain and to suppress the increase in the crosslinking density, thereby forming a cured product having a low crosslinking density. Thereby, the low elastic modulus and high elongation rate of the obtained polyurethane elastomer can be achieved. In addition, as described above, by using a monool compound, a high dielectric constant can be achieved and low electric field driving can be achieved. Furthermore, compared with the case where a plasticizer is added, the monool compound is incorporated into the cross-linked structure by reaction, so that a polymer actuator having a high gel fraction and hardly bleeding out can be achieved. In other words, the use of a monool compound containing one active hydrogen group in the molecule for a polymer actuator composed of a polyurethane elastomer molded product provides excellent flexibility and elongation, low electric field drive, and low bleed out properties. Are compatible.

  In the polyurethane elastomer composition, an equivalent ratio (NCO group / OH group) of an isocyanate group (NCO group) of the polyisocyanate component and an active hydrogen group (for example, OH group) of the active hydrogen component and monool compound is as described above. Although it varies depending on the concentration of the monool compound, it is desirably 0.80 to 1.20, preferably 0.95 to 1.05. If the equivalent ratio (NCO group / OH group) is less than 0.80, the crosslink density becomes too low and the handling property deteriorates. If it exceeds 1.20, it is difficult to achieve a low elastic modulus.

  As the catalyst used in the polyurethane composition, known catalysts can be used without limitation, but triethylenediamine, N, N, N ′, N′-tetramethylhexanediamine, bis (2-dimethylaminoethyl) Metal catalysts such as tertiary amines such as ether, bismuth octylate, tin octylate, di-n-butyltin dilaurate, and lead octylate can be used. These may be used alone or in combination of two or more.

  As a commercial product of the above catalyst, lead octylate marketed under the trade name “24% hexoate lead” from Toei Chemical Co., Ltd., bismuth octylate marketed under the trade name “Pucat 25” from Nippon Chemical Industry Co., Ltd., "TEDA-L33" manufactured by Tosoh Corporation, "NIAX CATALYST A1" manufactured by Momentive Performance Materials, "Caoriser No. 1" manufactured by Kao Corporation, "DABCO T-9" manufactured by Air Products And “BTT-24” manufactured by Toei Chemical Co., Ltd.

The polymer actuator of the present invention comprises a polyisocyanate component, an active hydrogen component containing two or more active hydrogen groups in the molecule, a monool compound containing one active hydrogen group in the molecule, and a polyurethane elastomer containing a catalyst. It is comprised from the polyurethane elastomer molded article formed from a composition. As described above, since the monool compound has a lower molecular weight than the active hydrogen component and thus has high reactivity, when the monool compound and the active hydrogen component are simultaneously reacted with the polyisocyanate component, the molecular chain is increased. The suppression effect of increasing the molecular weight and the suppression effect of increasing the crosslink density become too large. In an extreme case, the molded product cannot be formed without being cured. Therefore, the method for producing the polymer actuator of the present invention includes:
(I) a step of preparing a urethane group-containing compound A by reacting a monool compound containing one active hydrogen group with a polyisocyanate component,
(Ii) a step of preparing an isocyanate-terminated compound B from an active hydrogen component containing two or more active hydrogen groups and a polyisocyanate component;
(Iii) mixing the compounds A and B to form a mixture; and (iv) reacting the mixture with an active hydrogen component in the presence of the catalyst to form a polyurethane elastomer molded article. Is desirable.

  In the step (i), the isocyanate group (NCO group) of the polyisocyanate component and the active hydrogen group (for example, OH group) of the monool compound as a blending ratio of the polyisocyanate component and the monool compound. The equivalent ratio (NCO group / OH group) is 1.2 to 3.0, preferably 1.3 to 2.5. If the equivalent ratio (NCO group / OH group) is less than 1.2, the viscosity of the urethane group-containing compound A obtained tends to be too high, and if it exceeds 3.0, the effect of improving the dielectric constant due to the addition of the monool compound. Becomes smaller. The reaction conditions in the above step (i) are preferably 60 to 120 ° C. and 1 to 8 hours.

  In the step (ii), the isocyanate group (NCO group) of the polyisocyanate component and the active hydrogen group (for example, OH group) of the active hydrogen component as a mixing ratio of the polyisocyanate component and the active hydrogen component. The equivalent ratio (NCO group / OH group) is 1.5 to 3.0, preferably 1.8 to 2.5. If the equivalent ratio (NCO group / OH group) is less than 1.5, the viscosity of the resulting urethane group-containing compound B tends to be too high, and if it exceeds 3.0, the non-uniformity of crosslinking during curing increases. The actuator becomes difficult to drive with a low electric field. As reaction conditions in the said process (ii), 1 to 8 hours are preferable at 60-120 degreeC.

  The mixing apparatus used in the above steps (iii) and (iv) is not particularly limited as long as it can mix liquids with each other. For example, a hybrid mixer (manufactured by Keyence Corporation), a rotation / revolution mixer (stock) (Made by company Shinky).

  The method for forming the polyurethane elastomer molded product in the above step (iv) is a method using a molding die or a desired thickness by sandwiching a polyurethane elastomer composition between release-treated films having spacers in the case of a small thickness. A method of passing a nip roll with a controlled gap can be used. As said curing conditions, the temperature is 70-150 degreeC, Preferably it is 1-80 hours at 80-130 degreeC. When the curing temperature is less than 70 ° C., the curability of the polyurethane elastomer is insufficient, and when it exceeds 150 ° C., a large amount of by-products are generated. Further, when the curing time is less than 1 hour, the curability of the polyurethane elastomer is insufficient, and when it exceeds 24 hours, the polyurethane elastomer may be deteriorated.

  The obtained polyurethane elastomer can be produced in a desired shape, but may be a thin film, a film, or a sheet, and the thickness is 0.01 to 1.2 mm, preferably 0.05 to 1.0 mm. If the thickness is less than 0.01 mm, dielectric breakdown is likely to occur through defects in the film. If the thickness exceeds 1.2 mm, the applied electric field strength is reduced and the actuator is difficult to drive.

The resulting polyurethane elastomer has a gel fraction of 30% or more, preferably 40 to 95%, more preferably 45 to 90%. When the gel fraction is less than 30%, the bleed-out resistance is poor. The gel fraction was obtained by cutting the resulting polyurethane elastomer film into a width of 20 mm and a length of 50 mm and immersing in room temperature and toluene for 72 hours, then taking out the gel and drying until constant weight in a vacuum dryer at 100 ° C. And obtained from the following equation.
Gel fraction (%) = Wg / Wi × 100
Wi: Weight of initial sample Wg: Weight of gel after drying

  A polymer actuator can be produced by forming electrodes on both surfaces of the polyurethane elastomer molded article. As the material of the electrode, for example, metals such as gold, platinum, aluminum, silver, and copper, carbon, carbon nanotubes, or conductive resins or conductive elastomers obtained by dispersing them in a resin can be used. As a method for forming the electrode, for example, a plasma CVD method, an ion sputtering coating method, a vacuum deposition method, screen printing, or the like can be used.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further in detail, this invention is not limited to these.

(I) Synthesis of prepolymer (Prepolymer A)
Polypropylene glycol (Asahi Glass Co., Ltd., “Exenol 3030”, number average molecular weight 3000, functional group number 3) 85.2 parts by mass was added as a polyether polyol to the reaction vessel, and vacuum dehydration was performed for 1 hour with stirring. Thereafter, the inside of the reaction vessel was purged with nitrogen. Then, 14.8 parts by mass of 2,4-tolylene diisocyanate (manufactured by Mitsui Chemicals, “Cosmonate T-100”) was added to the reaction vessel, and the temperature in the reaction vessel was maintained at 80 ° C. 3 By reacting for a period of time, an isocyanate-terminated prepolymer was synthesized.

(Prepolymer B)
Into the reaction vessel, 68.9 parts by mass of 2,2,4-trimethylhexamethylene diisocyanate (Evonik Degussa, “Vestanut TMDI”) was placed, and vacuum dehydration was performed for 1 hour with stirring. Thereafter, the reaction vessel was purged with nitrogen, 31.1 parts by mass of ethylene cyanohydrin (manufactured by Tokyo Chemical Industry Co., Ltd., number average molecular weight 71.1) was added to the reaction vessel, and the temperature in the reaction vessel was adjusted to 100 ° C. Prepolymer B was synthesized by reacting for 6 hours while maintaining.

(Prepolymer C to H)
In the same manner as the prepolymer B except that the amount of 2,2,4-trimethylhexamethylene diisocyanate and the kind and amount of monool compound were as shown in Tables 1 and 2 below, H was synthesized.

(Example 1)
A mixed solution of 50 parts by mass of the prepolymer A and 50 parts by mass of the prepolymer B was prepared and degassed under reduced pressure. Subsequently, 151.9 parts by mass of polypropylene glycol (Asahi Glass Co., Ltd., “Exenol 3030”, number average molecular weight 3000, functional group number 3) and bismuth octylate (Nippon Chemical Industry Co., Ltd. “Pucat 25”) 0.30 mass The liquid which mixed and degassed the part was added to the mixed liquid, and mixed and defoamed with a hybrid mixer (manufactured by Keyence Corporation). The reaction solution was dropped onto a release-treated polyethylene terephthalate film having a 0.4 mm spacer, and the release-treated polyethylene terephthalate film was covered thereon, and the thickness was adjusted to 0.4 mm with a nip roll. Thereafter, curing was performed at 80 ° C. for 1 hour to obtain a polyurethane elastomer film having a monool compound concentration of 0.87 meq / g.

  The produced film was subjected to 200% biaxial stretching treatment, and fixed to a polypropylene frame having a diameter of 60 mm. Carbon grease was applied to the fixed film so as to have a diameter of 15 mm to produce an actuator element.

(Examples 2-8 and 11)
A polyurethane elastomer film actuator was produced in the same manner as in Example 1 except that the mixed liquid at the time of production of the polyurethane elastomer film was changed to the formulation shown in Tables 3 to 4 below.

Example 9
To 100 parts by mass of the prepolymer A, polypropylene glycol (Asahi Glass Co., Ltd., “Exenol 3030”, number average molecular weight 3000, functional group number 3) 17.2 parts by mass, ethylene cyanohydrin (Tokyo Chemical Industry Co., Ltd., number average molecular weight 71) .1) Implemented except that 4.8 parts by mass and bismuth octylate (Nippon Chemical Industry Co., Ltd. “Pucat 25”) 0.15 parts by mass were mixed and degassed, mixed and vacuum degassed. In the same manner as in Example 1, a polyurethane elastomer film actuator was produced.

(Example 10)
To 100 parts by mass of the prepolymer A, polypropylene glycol (Asahi Glass Co., Ltd., “Exenol 3030”, number average molecular weight 3000, functional group number 3) 16.6 parts by mass, n-propyl alcohol (Nacalai Tesque Co., Ltd., number average molecular weight) 60.1) 4.1 parts by mass and bismuth octylate (Nippon Chemical Industry Co., Ltd. “Pucat 25”) 0.15 parts by mass were mixed and degassed, and mixed and degassed under reduced pressure. In the same manner as in Example 1, a polyurethane elastomer film actuator was produced.

(Comparative Example 1)
To 100 parts by mass of the prepolymer A (without monool compound), 85.2 parts by mass of polypropylene glycol (Asahi Glass Co., Ltd., “Exenol 3030”, number average molecular weight 3000, functional group number 3) and bismuth octylate (Nippon Chemical Industrial Co., Ltd.) A polyurethane elastomer film actuator was prepared in the same manner as in Example 1 except that 0.22 parts by mass of a mixed and defoamed liquid was added, mixed and vacuum degassed.

(Comparative Example 2)
In the same manner as in Comparative Example 1, except that 100 parts by mass of the above prepolymer A was mixed with 740.8 parts by mass of the above-mentioned polypropylene glycol, bismuth octylate and dioctyl phthalate (manufactured by Sankyo Chemical Co., Ltd.) and degassed. Thus, a polyurethane elastomer film actuator was produced.

(Comparative Examples 3-4)
A polyurethane elastomer film actuator was produced in the same manner as in Example 1 except that the mixed liquid at the time of producing the polyurethane elastomer film was changed to the formulation shown in Table 5 below.

(Comparative Example 5)
To 100 parts by mass of the above prepolymer A (without monool compound), polypropylene glycol (Asahi Glass Co., Ltd., “Exenol 3030”, number average molecular weight 3000, functional group number 3) 8.9 parts by mass, ethylene cyanohydrin (Tokyo Chemical Industry Co., Ltd.) Manufactured, number average molecular weight 71.1) 5.4 parts by mass and bismuth octylate (Nippon Kagaku Sangyo Co., Ltd. “Pucat 25”) 0.14 parts by mass were mixed and degassed, mixed, depressurized A polyurethane elastomer film actuator was produced in the same manner as in Example 1 except for defoaming.

  Table 3 shows the elastomer blends of Examples 1 to 6, Table 4 lists the elastomer blends of Examples 7 to 11, and Table 5 summarizes the elastomer blends of Comparative Examples 1 to 5 in mass parts. The polyurethane elastomer film actuator obtained as described above was evaluated or measured for the monool compound concentration, 100% modulus, dielectric constant, elongation rate, gel fraction, and bleed-out resistance, and the results are shown in Tables 3-5. . The test method is as follows.

(Test method)
(1) 100% modulus The produced film was punched with a No. 7 dumbbell (test piece size: width 2 mm x length 12 mm), and autograph AG-X (manufactured by Shimadzu Corporation) in accordance with JIS K-7312 at room temperature. ) Was used to measure the modulus value at 100% elongation when a tensile test was conducted at a tensile speed of 500 mm / min.

(2) Dielectric constant The produced film was subjected to Au deposition using an ion sputtering apparatus JFC-1500 (manufactured by JEOL Ltd.) so that the effective electrode area was 30 mm in diameter, and equipped with a 1296 type dielectric constant measurement interface. The dielectric constant was measured using a 1255B type impedance analyzer (manufactured by Solartron). The applied voltage during measurement was 0.1 V, and the sweep frequency was 10 to 10 ⁶ Hz. The table shows a value of 1000 Hz.

(3) Expansion rate The manufactured actuator element was connected to a DC high-voltage power supply (Matsusada Precision Co., Ltd., HJPM-5R0.6-SP) through a copper foil, and the change in the expansion rate with respect to the applied voltage was measured. The table shows a value of 5 MV / m. The elongation rate was determined from the following formula.
Elongation rate (%) = [√ (S ₂ / S ₁ −1)] × 100
S ₁ : Film area before stretching S ₂ : Film area after voltage application

(4) Gel fraction The produced film was cut into a width of 20 mm and a length of 50 mm and immersed in toluene at room temperature for 72 hours. Thereafter, the gel was taken out and dried in a vacuum dryer at 100 ° C. until a constant weight was obtained. The gel fraction was determined from the following formula.
Gel fraction (%) = Wg / Wi × 100
Wi: Weight of initial sample Wg: Weight of gel after drying

(5) Bleed-out resistance The prepared film is allowed to stand on the release paper, “○” if there is no deposit on the release paper after one week, and “△” if there is some deposit but there is no problem. ", When there were many deposits, it evaluated as" x ".

*: Since it did not harden, a sample piece could not be prepared and measurement was not possible.
(Note 1) 2,4-tolylene diisocyanate commercially available under the trade name “Cosmonate T-100” from Mitsui Chemicals, Inc. (Note 2) The trade name “VESTANAT (registered trademark)” from Evonik Degussa ) TMDI ”, 2,2,4-trimethylhexamethylene diisocyanate (Note 3) Trifunctional polyether polyol marketed by Asahi Glass Co., Ltd. under the trade name“ Excenol 3030 ”; number average molecular weight (Mn) 3000
(Note 4) Ethylene cyanohydrin commercially available from Tokyo Chemical Industry Co., Ltd .; number average molecular weight (Mn) 71.1
(Note 5) n-propyl alcohol commercially available from Nacalai Tesque, Inc .; number average molecular weight (Mn) 60.1
(Note 6) m-nitrobenzyl alcohol commercially available from Tokyo Chemical Industry Co., Ltd .; number average molecular weight (Mn) 153.14
(Note 7) Bismuth octylate commercially available from Nippon Chemical Industry Co., Ltd. under the trade name “Pucat 25” (Note 8) Dioctyl phthalate commercially available from Sankyo Chemical Co., Ltd. under the trade name “DOP” (Note 9) ) NCO index: (equivalent of NCO group) / (equivalent of active hydrogen group)

  As is clear from the results shown in Tables 4 to 6, the polymer actuators of the present invention of Examples 1 to 11 have a lower 100% modulus and dielectric properties than the conventional polymer actuators of Comparative Examples 1 to 5. The ratio was high, the elongation ratio was large, the gel fraction was large, and the bleed-out resistance was excellent.

  In contrast, the polymer actuator of Comparative Example 1 does not use a monool compound, so the gel fraction is high and the bleed-out resistance is excellent, but the 100% modulus and dielectric constant are low, and the elongation rate is low. It was very low. The polymer actuator of Comparative Example 2 uses a large amount of low-molecular components such as dioctyl phthalate as a plasticizer, so that the 100% modulus is low, but the dielectric constant and gel fraction are low, and the bleed-out resistance The sex was very bad.

  The polymer actuators of Comparative Examples 3 and 4 were obtained by increasing the amount of the monool compound of Examples 1 and 2. However, because they did not cure, sample pieces could not be produced and the above characteristics could not be measured or evaluated. . The polymer actuator of Comparative Example 5 was prepared by adding a monool compound to the polyol component side without making it a prepolymer with an isocyanate component, but because it did not cure, a sample piece could not be prepared, and the above characteristics were measured or Evaluation was not possible.

  The polymer actuator of the present invention is excellent in flexibility and expansion ratio, and can be driven even in a low electric field. Sensors, optical switches, diaphragms, braille displays, power generation applications such as wave power generation and wind power generation, industrial It can be used for applications such as robots for nursing and nursing care, and medical equipment.

DESCRIPTION OF SYMBOLS 1 ... Polymer actuator 2 ... Electrode 3 ... Polyurethane elastomer

Claims (6)

A polymer actuator composed of a polyurethane elastomer formed from a polyurethane elastomer composition containing a polyisocyanate component, an active hydrogen component and a catalyst,
The polyurethane elastomer composition contains a monool compound containing one active hydrogen group in the molecule at a concentration of 0.20 to 1.00 meq / g,
A polymer actuator, wherein the polyurethane elastomer has a gel fraction of 30% or more.   The polymer actuator according to claim 1, wherein the monool compound has at least one functional group selected from the group consisting of an n-propyl group, a cyano group, and a nitro group.   The polyurethane elastomer reacts a urethane group-containing compound obtained by reacting a monool compound containing one active hydrogen group in the molecule with a polyisocyanate component, and the active hydrogen component and the polyisocyanate component. The polymer actuator according to claim 1, wherein the polymer actuator is obtained by reacting a mixture with an isocyanate-terminated compound obtained in this manner with the active hydrogen component. Polyurethane elastomer formed from a polyisocyanate component, an active hydrogen component containing two or more active hydrogen groups in the molecule, a monool compound containing one active hydrogen group in the molecule, and a polyurethane elastomer composition containing a catalyst A method for producing a polymer actuator comprising a molded article,
A step of preparing a urethane group-containing compound A by reacting a monool compound containing one active hydrogen group in the molecule with a polyisocyanate component,
A step of preparing an isocyanate-terminated compound B by reacting an active hydrogen component containing two or more active hydrogen groups in the molecule with a polyisocyanate component;
A method for producing a polymer actuator comprising: mixing the compounds A and B to form a mixture; and reacting the mixture with the active hydrogen component in the presence of the catalyst to form a polyurethane elastomer molded article .   The method for producing a polymer actuator according to claim 4, wherein the concentration of the monool compound is 0.20 to 1.00 meq / g.   6. The method for producing a polymer actuator according to claim 4, wherein the monool compound has at least one functional group selected from an n-propyl group, a cyano group, and a nitro group.

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