JP2012201723A - Ion gel with film and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ion gel with film, which can form an electrolyte having a desired shape and dimension, or the like, and further can chemically or physically stabilize ion liquid.SOLUTION: The ion gel with film 10 includes a film 14 formed on the surface of a core 12 composed of ion gel. The core 12 (ion gel) is a compatible compound of a first polymer and ion liquid, which is formed by taking the ion liquid into the network of the first polymer. Meanwhile, the film 14 is formed from a reaction product (polymer) obtained by mutually reacting the first polymer contained in the core 12 and a second polymer.

Description

  The present invention relates to an ion gel with a film that exhibits ion conductivity and is suitable as an electrolyte used in a fuel cell, for example, and a method for producing the same.

The ionic liquid is known as a liquid exhibiting a property of conducting various ions such as proton (H ⁺ ) and lithium ion (Li ⁺ ). Furthermore, the vapor pressure is below the lower limit of measurement, and the coagulation temperature is low. In other words, it hardly volatilizes and hardly changes to a solid phase even in a cold region. Therefore, it can be an excellent ionic conductor over a wide temperature range. For this reason, an ionic liquid can become a suitable electrolyte of various devices, such as a fuel cell, a secondary battery, a capacitor, and a dye-sensitized solar cell.

  However, when the electrolyte is a liquid, there is a concern that the above-described device may be damaged for some reason or the electrolyte may leak when the sealing function is deteriorated due to vibration applied to the device.

  In order to dispel this concern, as described in Non-Patent Document 1, it is considered effective to gel the ionic liquid into an ionic gel. In this case, the ionic liquid is taken into the network formed by the polymer and becomes compatible with the polymer, thereby forming a solid phase (that is, an ionic gel) that exhibits elasticity. When such a solid-phase ion gel is employed as the electrolyte, even if the device is damaged, leakage due to the electrolyte being in the solid phase is avoided.

Shiro Seki et al., “Journal of Physics Chem. B”, 2005, Vol. 109, No. 9, pp. 3886-3892.

  According to the description of Non-Patent Document 1, the ionic gel is obtained as follows. That is, first, a monomer, a crosslinking agent, and a polymerization initiator, which are polymer raw materials, are dissolved in an ionic liquid to prepare a polymerization solution.

  Next, this polymerization solution is poured into a mold, and then the monomer is polymerized in the mold. Along with this polymerization, a polymer is produced and an ionic liquid is taken into the polymer network. In other words, the polymer and the ionic liquid are compatibilized to form an ionic gel.

  As can be understood from this, according to the manufacturing method disclosed in Non-Patent Document 1, the ion gel can only be obtained as a bulk body corresponding to the shape of the mold (cavity). That is, this manufacturing method has a problem that the ion gel cannot be obtained in a desired shape.

  Further, as is well known, gels have extremely large elasticity, and therefore have poor plasticity. Therefore, the ion gel obtained according to the description of Non-Patent Document 1 cannot be formed into a desired shape by performing press molding. Furthermore, it is impossible to perform injection molding using ion gel.

  As described above, the manufacturing method disclosed in Non-Patent Document 1 has a problem that the ion gel cannot be obtained in an appropriate shape / dimension corresponding to the shape / dimension of the device.

  Furthermore, when an ion gel exhibiting proton conductivity is used as an electrolyte for a fuel cell, there is a concern that the ionic liquid may be discharged outside the fuel cell. That is, in the fuel cell, water is generated at the interface between the electrolyte and the electrode by a power generation reaction. On the other hand, the ionic liquid exhibiting proton conductivity is generally highly hydrophilic, and therefore, the ionic liquid contained in the electrolyte may move to water as a reaction product. Since water is discharged to the outside of the fuel cell, when the ionic liquid moves to the water, the ionic liquid is also discharged at the same time.

  When such a situation occurs, the amount of ionic liquid that is an ionic conductor is reduced, so that the power generation performance of the fuel cell is degraded.

  The present invention has been made in order to solve the above-described problems, and can form an electrolyte having a desired shape and size, and can further stabilize an ionic liquid chemically or physically. And it aims at providing the manufacturing method.

In order to achieve the above object, the present invention is an ion gel with a film in which a film made of a polymer is formed on the surface of an ion gel made of a compatible compound of a polymer and an ionic liquid, and is a granule,
The film is a reaction product of the polymer contained in the ion gel and another polymer.

  In such a configuration, the ion gel is shielded by the film. Therefore, even when a substance having a high affinity for the ionic liquid in the ionic gel and the ionic gel with a film come into contact, the ionic liquid is prevented from moving from the ionic gel to the substance, in other words, the ionic liquid is prevented from being washed away. The That is, the film performs a blocking action, whereby the ionic gel is physically and chemically stabilized.

  Moreover, since it is a granule, it is rich in plasticity. For this reason, it is possible to fill the ion gel with a film in a shape corresponding to the shape of the filling portion, or to obtain an aggregate (or compacted body) having a desired shape. Therefore, for example, the shape of the aggregate (or compacted body) of the ion gel with film can be set according to the shape of the device such as the electrolyte of the fuel cell.

  The particle size of the ion gel with film is preferably in the range of 1 nm to 1 mm, and the thickness of the film is preferably 0.1 nm to 100 nm. The particle diameter is defined as an average value of the major axis and the minor axis of a granule (substantially oval or perfect circle) visually recognized as a two-dimensional plane by a scanning electron microscope.

  When the particle size is smaller than 1 nm, the number of molecules of the ion gel becomes insufficient, and the ionic conductivity tends to decrease. On the other hand, when the thickness exceeds 1 mm, it is not easy to prevent the ion gel from leaking from the film when the film is damaged.

  On the other hand, when the thickness of the film is less than 0.1 nm, it is not easy to ensure the strength as the film. On the other hand, if it exceeds 100 nm, the resistance to ionic conduction increases.

Further, the present invention is a method for producing an ion gel with a film in which a film made of a polymer is formed on the surface of an ion gel made of a compatible compound of a polymer and an ionic liquid, and is a granule,
A step of preparing a first mixed solution by mixing an ion gel monomer, which is a raw material of the ion gel, and an ionic liquid;
A second mixed solution is prepared by mixing a solvent that causes phase separation with respect to the ionic liquid when the ionic liquid is added and the first mixed solution, and an emulsion is generated in the second mixed solution. A process of
A step of polymerizing the monomer for ionic gel contained in the emulsion to form a first polymer, and compatibilizing the first polymer with the ionic liquid to obtain a granular ionic gel;
Mixing a solution containing a second polymer that interacts with the first polymer with a solution containing the ion gel to prepare a third mixed solution;
The first polymer contained in the ion gel is reacted with the second polymer in the third mixed solution to form a film made of a polymer as a reaction product on the surface of the ion gel. To obtain a coated ion gel,
It is characterized by having.

  By going through such a process, the above-mentioned ion gel with a film can be easily obtained.

  The second mixed solution is preferably cooled in the step of forming an emulsion and the step of polymerizing the monomer for ion gel. This is because an emulsion is relatively easily broken at high temperatures, and it becomes difficult to obtain an ionic gel as granules.

  Moreover, it is preferable to prepare the said 2nd mixed solution as what contains surfactant. By the action of this surfactant, the formation of the emulsion is promoted and the formed emulsion is prevented from being broken. Therefore, it becomes easy to obtain a fine emulsion and thus a fine ion gel.

  In any case, it is preferable to obtain the ion gel with a coating as a ionic liquid encapsulant having a particle size in the range of 1 nm to 1 mm and a thickness of the coating of 0.1 nm to 100 nm. The particle size and the film thickness can be adjusted, for example, by appropriately setting the reaction time.

  According to the present invention, the ion gel, which is a compatible material of the first polymer and the ionic liquid, is protected by the film, so that the ionic gel, and hence the ionic liquid in the ionic gel, is physically or chemically stable. It can be made. Therefore, for example, it is possible to prevent the ionic liquid from flowing out even when the ionic gel with a film comes into contact with a substance having a high affinity with the ionic liquid. For this reason, ion conductivity is stabilized.

  In addition, since the ion gel with a film is a fine granule, it is rich in plasticity. Therefore, it is possible to form a filler or agglomerate (or powder compact) having a desired shape. Therefore, by using this ion gel with a film to produce a filler or an aggregate (or compacted body), for example, the fuel cell electrolyte can be obtained in a desired shape.

It is typical sectional drawing of the ion gel with a film | membrane which concerns on embodiment of this invention. 2 is an optical micrograph of an ion gel that is a film-coated ion gel of Example 1. FIG. 2 is an optical micrograph of an ion gel that is an ion gel with a film according to Example 2. FIG. 4 is an optical micrograph of an ion gel that is an ion gel with a film of Example 3. FIG.

  Hereinafter, preferred embodiments of the ion gel with a film and the method for producing the same according to the present invention will be described in detail with reference to the accompanying drawings.

  First, an ion gel with a film will be schematically described with reference to FIG.

  FIG. 1 is a schematic cross-sectional view of a coated ion gel 10. The ion gel 10 with a film is a fine granule formed by coating a core 12 made of an ion gel with a film 14 made of a polymer, in other words, a fine particle. In this case, the coated ion gel 10 is approximately approximate to a sphere.

  In FIG. 1, the cross section along the diameter of the ion gel 10 with a film | membrane is shown. As described above, the particle diameter of the ion gel 10 with a film is shown as an average value of D1 and D2 in FIG. 1, but in this case, D1 and D2 are substantially equal.

  The ionic gel forming the core 12 is made of a compatible compound of an ionic liquid and a polymer. That is, the ionic liquid is formed by being taken into the polymer network.

  When the ion gel with film 10 is employed as an electrolyte, a substance capable of conducting target ions may be selected as the ionic liquid. For example, when a fuel cell electrolyte is used, a substance capable of conducting protons is selected. Specifically, dimethylethylamine trifluoromethanesulfonate, diethylmethylamine methanesulfonate, diethylmethylamine bis (trifluoromethane) sulfonimide, dimethylethylamine bis (trifluoromethane) sulfonimide, 1-ethyl-3-methylimidazolium bis (trimethyl) Fluoromethylsulfonyl) imide, 1-ethyl-3-methylimidazolium methanesulfonate, and the like.

On the other hand, as the polymer, a polymer having a reactive functional group is selected while taking the ionic liquid to be used into the network to form a compatible compound. Here, examples of the reactive functional group include those that form a salt and those that form a covalent bond. Among these, an acid group and a basic group are present in those that form salts. Preferred examples of the acid group include —COOH, —SO ₃ H, —OP (OH) _{3, and the} like. Preferable examples of the sex group include —NH, —OH, —SH and the like. On the other hand, preferred examples of the reactive functional group that forms a covalent bond include —NH, —C (═O) —R, —C═C—R, —C (═O) NH, and the like. R represents an organic group.

  Examples of such polymers include those obtained by polymerizing polymerizable vinyl monomers such as methyl acrylate, acrylic acid, methyl methacrylate, methacrylic acid, acrylamide, acrylonitrile, hydroxyethyl methacrylate, vinyl acetate, and those shown below. Can be mentioned.

  The polymer forming the film 14 is a reaction product of a polymer contained in the ion gel forming the core 12 and a polymer different from the polymer. Hereinafter, for convenience of explanation, the polymer contained in the ion gel is also referred to as “first polymer”, and the other polymer is also referred to as “second polymer”.

  As the second polymer, a polymer that interacts with the first polymer is selected. That is, it has a reactive functional group that reacts with the reactive functional group of the first polymer.

  Specifically, when the reactive functional group of the first polymer is an acidic group, a substance having a basic group is selected as the second polymer. On the other hand, when the reactive functional group of the first polymer is a basic group, a substance having an acidic group is selected as the second polymer.

  When the reactive functional group of the first polymer is —NH, the second polymer includes —C (═O) —R, —C═C—R, which forms a covalent bond with —NH, Alternatively, a substance having —C (═O) NH is selected, and conversely, the reactive functional group of the first polymer is —C (═O) —R, —C═C—R, or —C ( When ═O) NH, a substance having —NH which forms a covalent bond with any of these is selected.

  The thickness T of the film 14 is preferably 0.1 nm to 100 nm. If the thickness T is less than 0.1 nm, it is not easy to ensure the strength as the coating 14. On the other hand, if it exceeds 100 nm, the resistance to ionic conduction increases.

  The suitable particle diameter (average value of D1 and D2) of the ion gel 10 with a film having the core 12 and the film 14 as described above is in the range of 1 nm to 1 mm. When it is smaller than 1 nm, the number of molecules of the ion gel constituting the core 12 is not sufficient, and the ionic conductivity tends to decrease. If the thickness exceeds 1 mm, it is not easy to prevent the core 12 from leaking when the coating 14 is damaged. A more preferable particle diameter of the ion gel 10 with a film is 10 nm to 100 μm.

  In the ion gel 10 with a film configured as described above, the core 12 (ion gel) is protected by the film 14. Therefore, even if a substance having high affinity for the ionic liquid in the ionic gel and the ion gel 10 with a film come into contact with each other, the ionic liquid is prevented from moving from the ionic gel to the substance. This is because the film 14 performs a blocking action.

  That is, the provision of the coating 14 makes it easy to maintain the ionic liquid in a chemically or physically stable state. For this reason, when the ion gel 10 with a film is used as an electrolyte of a fuel cell, the ionic liquid contained in the core 12 is prevented from moving to the generated water, and consequently, accompanying the generated water and being discharged outside the fuel cell. As a result, the power generation performance of the fuel cell can be maintained.

  Moreover, the ion gel 10 with a film | membrane is a very fine microparticle as mentioned above. For this reason, it can fill with the shape corresponding to the shape of a filling location, or it can be set as the aggregate (or compacting body) of desired shape. Accordingly, when obtaining an electrolyte for a fuel cell from the ion gel 10 with a film, for example, fine particles of the ion gel 10 with a film may be filled in a sealing member formed in a predetermined shape in advance.

  Thus, according to this Embodiment, the electrolyte of the desired shape according to a device can be obtained. In addition, in this case, since the electrolyte has the coating 14, it is difficult for damage to occur, and even if the damage occurs, the core 12 is a gel, so that it does not easily flow out of the coating 14. Therefore, the concern that the ionic liquid that is the ionic conductor leaks can be eliminated.

  Next, the manufacturing method of the above-mentioned ion gel 10 with a film | membrane is demonstrated.

  First, an ionic liquid for obtaining an ionic gel and an ionic gel monomer are mixed to prepare a first mixed solution. Furthermore, at least one of a polymerization initiator and a crosslinking agent for promoting the polymerization of the monomer for ion gel can be added to the first mixed solution.

  As the ionic liquid, a substance as described above may be used. Moreover, what is necessary is just to select polymerizable vinyl monomers, such as methyl acrylate, acrylic acid, methyl methacrylate, methacrylic acid, acrylamide, acrylonitrile, hydroxyethyl methacrylate, vinyl acetate, and the following, as an ion gel monomer.

  In this case, as the polymerization initiator, a substance that promotes the polymerization of the monomer for ion gel and is soluble in the ionic liquid is selected. Preferable examples thereof include lauroyl peroxide, azobisisobutyronitrile, 2,2′-azobis (2-methylpropionamide) dihydrochloride, benzoyl peroxide, and the like that can generate radicals upon decomposition. Can be mentioned.

  Further, as the crosslinking agent, a substance that can crosslink the network formed by the polymerization of the above-mentioned monomer for ion gel and is soluble in the ionic liquid is selected. Preferable examples thereof include N, N-methylenebisacrylamide, ethylene glycol dimethacrylate, polyethyleneamine, glutaraldehyde and the like.

  On the other hand, a solvent that causes phase separation for the ionic liquid when mixed with the ionic liquid is prepared. The solvent is not particularly limited as long as it can be separated into two phases from the ionic liquid. When the ionic liquid is the above-mentioned substance, preferable examples thereof include n-hexane, n-dodecane, Examples include toluene and water. Especially in the case of water, there is an advantage that it is inexpensive and extremely easy to obtain.

  In addition, it is preferable to add surfactant to this solvent for the reason mentioned later. When the ionic liquid is hydrophobic and the solvent is water, a suitable example of the surfactant is a nonionic surfactant having an HLB value of 12 or more. On the other hand, when the ionic liquid is hydrophilic and the solvent is a hydrophobic organic solvent, the HLB value is preferably 6 or less.

  Next, this solvent is mixed with the first mixed solution prepared as described above. Thereby, the second mixed solution is prepared.

  In this mixing, forcible mechanical stirring is performed using a magnetic stirrer, stirring blade, homogenizer, ultrasonic dispersion device, or the like. Thereby, an emulsion is formed with the monomer for ionic gel and the ionic liquid. In addition, when a surfactant is added to the solvent, the second mixed solution is prepared as a surfactant added. In this case, the formation of the emulsion is promoted by the action of the surfactant, and the formed emulsion is inhibited from being destroyed. That is, it becomes easy to maintain the emulsion in a fine shape.

  When the temperature of the second mixed solution is excessively high, the emulsion tends to be easily broken. Therefore, it is preferable to cool the container containing the second mixed solution by immersing it in an oil bath or the like so as to keep the temperature of the second mixed solution at 40 ° C. or lower.

  If left in this state, the polymerization of the monomer for ion gel in the emulsion starts spontaneously and proceeds. Or you may make it start superposition | polymerization by irradiating an ultraviolet-ray to such an extent that the temperature of a 2nd mixed solution does not rise. If the temperature of the second mixed solution rises excessively, there is a concern that the emulsion may be destroyed as described above. Therefore, it is more preferable to cool the second mixed solution also in this step.

  As the polymerization of the monomer for ion gel proceeds, a first polymer network is formed, and an ionic liquid is taken into the network. As a result, an ion gel that is a compatible compound of the first polymer and the ionic liquid is generated. When the crosslinking agent is added, the first polymer is generated as a crosslinked polymer.

  The ion gel is fine because it is formed by gelation of each emulsion. That is, it becomes a fine particle having a particle diameter of 1 nm to 1 mm. The particle size can be adjusted, for example, by appropriately setting the reaction time.

  On the other hand, a solution containing the second polymer that forms the film 14 is prepared. For this purpose, for example, an ionic liquid identical to the ionic liquid used in preparing the first mixed solution, or an organic such as water, methanol, N-methylpyrrolidone, dimethylacetamide, N, N-dimethylformamide, dimethylsulfoxide, etc. The second polymer may be dissolved in the solvent. Of course, as the second polymer, one having a reactive functional group that interacts with the reactive functional group of the first polymer is selected.

  Next, this solution is mixed with the second mixed solution containing the ion gel. Thereby, a third mixed solution is prepared.

  If left in this state, the reactive functional group of the first polymer and the reactive functional group of the second polymer included in the ion gel begin to react with each other in the vicinity of the surface layer of the ion gel. As a result, a film 14 which is a reaction product of the first polymer and the second polymer is formed on the surface of the ion gel, and thereby the ion gel 10 with a film is obtained.

  0.5 g (2.1 mmol) of diethylmethylamine trifluoromethanesulfonate, which is an ionic liquid, was weighed and stored in a container with an open / close stopper. In contrast, 0.25 g (3.5 mmol) acrylic acid, 0.012 g (0.08 mmol) N, N-methylenebisacrylamide, 0.012 g (0.07 mmol) 2,2′-azobis (iso) Butyronitrile) was dissolved to prepare a first mixed solution.

  The first mixed solution was frozen with liquid nitrogen, and then the inside of the container with an open / close stopper was decompressed with a vacuum pump. By returning this to room temperature, the first mixed solution was dissolved. By repeating this operation three times, oxygen was removed from the first mixed solution and the inside of the container with an open / close stopper. Furthermore, Ar was filled in a container with an opening / closing stopper.

  On the other hand, Nikkor Decagrim 5-ISV (trade name of nonionic surfactant manufactured by Nikko Chemicals Co., Ltd., HLB = 3.5) is set to 0 with respect to 10 ml of n-dodecane stored in another container with an open / close stopper. .5 g dissolved was prepared. This is expressed as “n-dodecane dispersion medium”.

  After this n-dodecane dispersion medium was frozen with liquid nitrogen, the inside of the container with an open / close stopper was decompressed with a vacuum pump. By returning this to room temperature, the n-dodecane dispersion medium was dissolved. By repeating this operation three times, oxygen was removed from the n-dodecane dispersion medium and the inside of the container with an opening / closing stopper. Furthermore, Ar was filled in a container with an opening / closing stopper.

  As described above, oxygen that inhibits polymerization of acrylic acid was reduced.

  Next, in the glove box having an Ar atmosphere, the n-dodecane dispersion medium and the first mixed solution are mixed to prepare a second mixed solution, and by vigorously stirring for 60 minutes with a magnetic stirrer, The emulsion was dispersed in the second mixed solution.

  Next, while maintaining the second mixed solution at 5 ° C., the second mixed solution was irradiated with ultraviolet rays having a wavelength of 365 nm from an ultraviolet lamp to polymerize and crosslink acrylic acid. Thereby, an ionic gel in which an ionic liquid and a crosslinked polymer of acrylic acid were compatibilized was obtained as a product. An optical micrograph of the cross section of this product is shown in FIG.

  On the other hand, 0.15 g (3.5 mmol) of polyethyleneimine having a molecular weight of about 1200 was dissolved in 1 g of diethylmethylamine trifluoromethanesulfonate. This is referred to as a “polyethyleneimine solution”.

  After this polyethyleneimine solution and the second mixed solution were mixed to prepare a third mixed solution, the third mixed solution was stirred at room temperature for 24 hours. Thereby, the crosslinked polymer of acrylic acid contained in the ion gel and the polyethyleneimine in the third mixed solution caused an interaction, and a film was formed on the surface of the ion gel. That is, an ion gel with a film was obtained.

Next, the ion gel with a film precipitated by centrifugation was washed with n-dodecane, and further vacuum-dried at 60 ° C. to obtain a dry powder. When this dry powder was used and the proton conductivity was measured by a direct current four-terminal method at 120 ° C. in a hydrogen atmosphere, it was 2.4 × 10 ⁻² S / cm.

  Further, when the dry powder was immersed in distilled water and allowed to stand at room temperature for 12 hours, and then separated from distilled water by centrifugation and dried again, the weight loss accompanying elution in distilled water was 5.6% by weight. Met.

  The dissolved amounts of acrylic acid, N, N-methylenebisacrylamide, and 2,2′-azobis (isobutyronitrile) in the first mixed solution were 0.5 g (6.9 mmol) and 0.025 g (0.16 mmol), respectively. , 0.025 g (0.15 mmol), and in the same manner as in Example 1 except that the amount of polyethyleneimine dissolved in the polyethyleneimine solution was 0.3 g (7 mmol), An ion gel with a film on which a film made of a reaction product of a crosslinked polymer of acrylic acid and polyethyleneimine was formed was obtained. An optical micrograph of the ion gel before the film is formed is shown in FIG.

Then, using the dry powder obtained in the same manner as in Example 1, the proton conductivity was measured by the DC four-terminal method at 120 ° C. in a hydrogen atmosphere, and found to be 1.2 × 10 ⁻² S / cm. . Further, when the dry powder was immersed in distilled water and allowed to stand at room temperature for 12 hours, and then separated from distilled water by centrifugation and dried again, the weight loss accompanying elution in distilled water was 2.4% by weight. Met.

  The dissolved amounts of acrylic acid, N, N-methylenebisacrylamide, and 2,2′-azobis (isobutyronitrile) in the first mixed solution were 1 g (13.9 mmol), 0.05 g (0.32 mmol), 0 .05 g (0.3 mmol) and the surface of the ion gel in the same manner as in Examples 1 and 2 except that the amount of polyethyleneimine dissolved in the polyethyleneimine solution was 0.6 g (13.9 mmol). In addition, a film-coated ion gel was obtained in which a film composed of a reaction product of a crosslinked polymer of acrylic acid and polyethyleneimine was formed. FIG. 4 shows an optical micrograph of the ion gel before the film is formed.

Thereafter, the proton conductivity at 120 ° C. was measured by the DC four-terminal method in a hydrogen atmosphere in the same manner as in Examples 1 and 2, and it was 6.4 × 10 ⁻⁴ S / cm. Moreover, the weight reduction accompanying elution in distilled water was 1.6 weight%.

  In the same manner as in Examples 1 to 3, except that the polyethyleneimine aqueous solution was prepared by setting the amount of polyethyleneimine having a molecular weight of about 10,000 to 0.15 g (3.5 mmol), the surface of the ion gel was cross-linked with acrylic acid. A dry powder of an ion gel with a film on which a film made of a reaction product of a polymer and polyethyleneimine was formed was obtained.

With respect to this dry powder, proton conductivity at 120 ° C. was measured under a hydrogen atmosphere by a direct current four-terminal method, which was 5.1 × 10 ⁻² S / cm. Moreover, the weight loss accompanying elution in distilled water was 3.3% by weight.

  In the same manner as in Example 4 except that a polyethyleneimine aqueous solution was prepared by setting the amount of polyethyleneimine having a molecular weight of about 10,000 to 0.3 g (7 mmol), an acrylic acid cross-linked polymer and polyethylene were formed on the surface of the ionic gel. A dry powder of an ion gel with a film on which a film made of a reaction product with imine was formed was obtained.

This dry powder was measured for proton conductivity at 120 ° C. in a hydrogen atmosphere by the direct current four-terminal method and found to be 1.5 × 10 ⁻² S / cm. Moreover, the weight reduction accompanying elution in distilled water was 3.0 weight%.

  In the same manner as in Examples 4 and 5, except that a polyethyleneimine aqueous solution was prepared by setting the amount of polyethyleneimine having a molecular weight of about 10,000 to 0.6 g (13.9 mmol), crosslinking of acrylic acid was performed on the surface of the ion gel. A dry powder of an ion gel with a film on which a film made of a reaction product of a polymer and polyethyleneimine was formed was obtained.

With respect to this dry powder, the proton conductivity at 120 ° C. was measured in a hydrogen atmosphere by the direct current four-terminal method, and found to be 8.4 × 10 ⁻⁴ S / cm. Moreover, the weight loss accompanying elution in distilled water was 2.7% by weight.

Comparative example

  For comparison, the ionic gel (see FIG. 2) obtained during Example 1 was separated from the second mixed solution by centrifugation, washed with n-dodecane, and further vacuum dried at 60 ° C. To dry powder. When this dry powder was immersed in distilled water and allowed to stand at room temperature for 12 hours, and then separated from distilled water by centrifugation and dried again, the weight loss associated with elution in distilled water was 53.3% by weight. Yes, it was very large compared to Examples 1-6.

  From the above results, it is possible to sufficiently retain the ionic liquid even when it comes into contact with a substance having a high affinity with the ionic liquid, that is, it is difficult for the ionic liquid to flow out. It is clear.

10 ... Ion gel with coating 12 ... Core 14 ... Coating

Claims (6)

A film made of a polymer is formed on the surface of an ion gel made of a compatible compound of a polymer and an ionic liquid, and is an ion gel with a film that is a granule,
The ion gel with a film, wherein the film is a reaction product of the polymer contained in the ion gel and another polymer.   The ion gel with a film according to claim 1, wherein the particle diameter is in the range of 1 nm to 1 mm, and the thickness of the film is 0.1 nm to 100 nm. A method for producing a film-coated ion gel, in which a film made of a polymer is formed on the surface of an ion gel made of a compatible compound of a polymer and an ionic liquid,
A step of preparing a first mixed solution by mixing an ion gel monomer, which is a raw material of the ion gel, and an ionic liquid;
A second mixed solution is prepared by mixing a solvent that causes phase separation with respect to the ionic liquid when the ionic liquid is added and the first mixed solution, and an emulsion is generated in the second mixed solution. A process of
A step of polymerizing the monomer for ionic gel contained in the emulsion to form a first polymer, and compatibilizing the first polymer with the ionic liquid to obtain a granular ionic gel;
Mixing a solution containing a second polymer that interacts with the first polymer with a solution containing the ion gel to prepare a third mixed solution;
The first polymer contained in the ion gel is reacted with the second polymer in the third mixed solution to form a film made of a polymer as a reaction product on the surface of the ion gel. To obtain a coated ion gel,
The manufacturing method of the ion gel with a film | membrane characterized by having.   4. The method for producing a coated ion gel according to claim 3, wherein the second mixed solution is cooled in the step of forming the emulsion and the step of polymerizing the monomer for ion gel.   The method for producing a coated ion gel according to claim 3 or 4, wherein the second mixed solution is prepared as a surfactant.   The manufacturing method according to any one of claims 3 to 5, wherein a particle diameter is in a range of 1 nm to 1 mm and a thickness of the film is 0.1 nm to 100 nm. Manufacturing method of ion gel with film.

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