JP6985159B2 - Method for manufacturing an inorganic-organic composite film - Google Patents

Description

The present invention relates to a method for producing an inorganic organic composite film. More specifically, the present invention relates to a method for producing an inorganic-organic composite film having excellent productivity.

The inorganic-organic composite film is a film composed of an inorganic component such as a metal oxide and an organic component such as a resin. For example, various applications have been studied for various uses such as alkaline water electrolysis diaphragms and battery separators, and each use. So far, an inorganic-organic composite film having excellent properties required for the above has been developed.

Among these uses, for example, an alkaline water electrolysis diaphragm is a membrane used for electrolysis of water, which is one of the industrial methods for producing hydrogen, and is used to separate an anode chamber and a cathode chamber in an electrolytic cell. Used for.

The electrolysis of water is carried out by the movement of electrons (or ions). Therefore, in order to efficiently perform electrolysis, the diaphragm for alkaline water electrolysis is required to have high ion permeability. Further, a gas barrier property capable of blocking oxygen generated in the anode chamber and hydrogen generated in the cathode chamber is required. Further, since the electrolysis of water is carried out at 80 to 90 ° C. using alkaline water having a high concentration of about 30%, high temperature resistance and alkali resistance are also required.

Various inorganic and organic composite membranes for such alkaline water electrolysis diaphragms have been known so far.
For example, Patent Document 1 comprises a polymer porous layer containing at least one polymer compound among polyethersulfone and polysulfone, and an organic fiber cloth layer bonded to the polymer porous layer. Alkaline water electropolymerization macromolecules have been described and described that the porous layer further comprises titanium oxide, zirconium oxide and mixtures thereof for further improvement of the ion conductivity of the macromolecules.
Further, for example, Patent Document 2 describes a microporous membrane containing a polyphenylene copolymer having an average pore diameter, a maximum pore diameter, and a void ratio in a specific range, which is applied to a diaphragm for alkaline water electrolysis. It is described as containing hydrophilic inorganic particles.

JP-A-2015-117407 Japanese Unexamined Patent Publication No. 2017-66184

The inorganic-organic composite film as described above is produced by using, for example, a resin composition prepared by mixing inorganic particles (inorganic components) of a metal oxide or metal hydroxide and a resin component in a solvent. In recent years, the performance required for inorganic-organic composite films has increased, and aromatic hydrocarbon-based resins such as super engineering plastics have come to be used as resin components. However, such an aromatic hydrocarbon-based resin has a problem that the productivity of the inorganic-organic composite film is low because the solubility in a solvent is low and it takes a long time to dissolve.

The present invention has been made in view of the above situation, and an object of the present invention is to provide a method for producing an inorganic-organic composite film, which can efficiently produce an inorganic-organic composite film in a short time.

The present inventor has studied various methods for producing an inorganic-organic composite film, and found that a resin piece having an arithmetic average surface roughness (Ra) of 20 μm or more was used as an aromatic hydrocarbon-based resin as an organic component. We have found that the resin component can be dissolved in a solvent in a short time, and thereby an inorganic organic composite film having excellent dispersibility of inorganic particles can be efficiently produced in a short time, and the present invention has been completed.

That is, the present invention is a method for producing an inorganic organic composite film containing metal oxide particles and / or metal hydroxide particles and an aromatic hydrocarbon-based resin. / Or a step of mixing a metal hydroxide particle, a resin piece of an aromatic hydrocarbon resin, and a solvent to obtain a resin composition, and a step of forming a film using the resin composition, the above-mentioned resin. It is a method for producing an inorganic organic composite film, characterized in that the arithmetic average surface roughness (Ra) of a piece is 20 μm or more.

According to the method for producing an inorganic-organic composite film of the present invention, the inorganic-organic composite film can be efficiently produced in a short time. Further, the inorganic-organic composite film obtained by the production method of the present invention has excellent dispersibility of metal oxide particles and / or metal hydroxide particles, and can sufficiently exhibit the performance of the film. The method for producing an inorganic-organic composite film of the present invention can be particularly suitably applied as a method for producing various inorganic-organic composite films such as a diaphragm for alkaline water electrolysis and a separator for a battery.

The present invention will be described in detail below. It should be noted that a combination of two or more of the individual preferred embodiments of the present invention described below is also a preferred embodiment of the present invention. Further, in the present specification, "metal oxide particles and / or metal hydroxide particles" are also referred to as "metal (water) oxide particles".

<Manufacturing method of inorganic organic composite film>
The present invention is a method for producing an inorganic organic composite film containing metal oxide particles and / or metal hydroxide particles and an aromatic hydrocarbon-based resin, wherein the production method is for metal oxide particles and / or. Alternatively, a step of mixing a metal hydroxide particle, a resin piece of an aromatic hydrocarbon resin, and a solvent to obtain a resin composition (hereinafter, also referred to as a “mixing step”), and the above resin composition are used. It includes a step of forming a film (hereinafter, also referred to as a “deposition step”), and is characterized in that the arithmetic average surface roughness (Ra) of the resin piece is 20 μm or more.

In the method for producing an inorganic-organic composite film of the present invention, a resin piece of an aromatic hydrocarbon-based resin having an arithmetic average surface roughness (Ra) of 20 μm or more is used in the mixing step for preparing a resin composition. .. Thereby, the aromatic hydrocarbon-based resin can be easily dissolved in the solvent to prepare the resin composition in a short time, and the productivity of the inorganic-organic composite film can be improved.

By using a resin piece having an arithmetic average surface roughness (Ra) in a specific range as the aromatic hydrocarbon-based resin, the productivity of the inorganic-organic composite film can be improved in the normal resin form. Since the resin component can be dissolved in the solvent in a short time as compared with the case of a certain pellet, a resin composition in which the metal (water) oxide particles and the aromatic hydrocarbon resin are mixed and dispersed can be easily prepared. It is presumed that this is because it can be done.

In the above mixing step, the arithmetic average surface roughness (Ra) of the resin piece of the aromatic hydrocarbon resin is 30 μm or more in that the aromatic hydrocarbon resin can be dissolved in the solvent in a shorter time. It is preferably present, and more preferably 40 μm or more. The upper limit of the arithmetic average surface roughness (Ra) of the resin pieces is not particularly limited as long as the resin pieces can be easily dissolved in a solvent, but the entanglement of the resin pieces during weighing and charging is suppressed. In terms of points, 200 μm or less is preferable, and 100 μm or less is more preferable.
In the present specification, the arithmetic average surface roughness (Ra) can be measured by a method based on JIS B0601-2001, and is an average value when observing 10 fields of 500 μm square with respect to the resin piece. For example, it can be measured using a laser microscope having a 20x field (VK-9700 manufactured by KEYENCE CORPORATION).

Each step in the manufacturing method of the present invention will be described.
(1) Mixing Step In the method for producing an inorganic-organic composite film of the present invention, first, a metal (water) oxide particle, a resin piece of an aromatic hydrocarbon-based resin, and a solvent are mixed to form an inorganic-organic composite film. It has a step of obtaining a resin composition for forming. Each component used in the mixing step will be described.

(Metal (water) oxide particles)
The metal (water) oxide particles used in the present invention can be appropriately selected depending on the purpose and application of the inorganic-organic composite film, and specifically, for example, zirconium oxide, titanium oxide, aluminum oxide, and the like. Metal oxides such as iron oxide, zinc oxide, tin oxide and bismuth oxide; or metal hydroxides such as magnesium hydroxide, zirconium hydroxide and titanium hydroxide can be mentioned. Among them, metal hydroxide is preferable, magnesium hydroxide and zirconium hydroxide are more preferable, and magnesium hydroxide is further preferable, because it is inexpensive and can be suitably used for an alkaline water electrolysis diaphragm. The metal (water) oxide particles may be used alone or in combination of two or more.

The metal (water) oxide particles are not particularly limited and may be natural products or synthetic products. Further, the surface may be untreated, or may be surface-treated with a silane coupling agent, stearic acid, oleic acid, phosphoric acid ester or the like.

The shape of the metal (water) oxide particles is not particularly limited as long as it is a particle, and may be any shape such as amorphous, spherical, granular, flaky, and hexagonal plate. In particular, it is preferably amorphous, spherical, or flaky in that the dispersibility in the resin composition is further improved.

In the present invention, general commercial products can also be used as the metal (water) oxide particles. Examples of commercially available products that can be used in the present invention include 200-06H manufactured by Kyowa Chemical Industry Co., Ltd., UP650-1 manufactured by Ube Material Industries, Ltd., MAGSTAR # 20 manufactured by Tateho Chemical Industries Co., Ltd., # 200 manufactured by Kamishima Chemical Industry Co., Ltd., and the like. Magnesium hydroxide; Zirconium hydride manufactured by Daiichi Rare Element Industry Co., Ltd. and the like can be mentioned.

The average particle size of the metal (water) oxide particles may be appropriately designed according to the use of the inorganic-organic composite film, but is usually 0.05 to 2.0 μm, preferably 0.1 to 1.5 μm, and more. It is preferably 0.2 to 1.0 μm.
When the use of the inorganic-organic composite film is an alkaline water electrolysis diaphragm, the average particle size of the metal (water) oxide particles is preferably 0.1 to 1.1 in terms of excellent ion permeability and gas barrier properties. It is 5 μm, more preferably 0.2 to 1.0 μm.
The average particle size is the volume average particle size (D50) obtained from the particle size distribution measurement by the laser diffraction method. Specifically, the average particle size is obtained by dispersing the metal (water) oxide particles in ethanol and subjecting them to ultrasonic treatment, and then using a laser diffraction / scattering type particle size distribution measuring device (HORIBA, Ltd. “Model No. LA-”. It can be obtained by adjusting and measuring the transmittance specified by the apparatus using 920 ”).

The content of the metal (water) oxide particles is preferably 15 to 50% by mass, more preferably 16 to 47% by mass, and further preferably 18 to 44% by mass in the resin composition. ..

(Aromatic hydrocarbon resin)
In the present invention, in the above mixing step, a resin piece of an aromatic hydrocarbon-based resin having an arithmetic average surface roughness (Ra) of 20 μm or more is used. As a result, the resin component can be easily dissolved in the solvent to prepare the resin composition in a short time, and the productivity of the inorganic organic composite film can be improved.

The shape of the resin piece is not particularly limited as long as it satisfies the range of the above-mentioned arithmetic mean surface roughness (Ra), and examples thereof include an amorphous shape, a flaky shape, a spherical shape, a columnar shape, and a cylindrical shape. Of these, amorphous or flaky is preferable.

The bulk density of the resin piece is preferably ^{0.1 to 0.7 g / cm 3.} When the bulk density of the resin piece is in the above range, the aromatic hydrocarbon-based resin can be dissolved in the solvent in a shorter time, and the productivity of the inorganic-organic composite film can be further improved. The bulk density of the resin piece is more preferably 0.2 to 0.6 g / cm ^3, further preferably 0.25~0.5g / cm ^3.
In the present specification, the bulk density can be determined using the bulk density measuring instrument (manufactured by AS ONE Co. K AM-01).

The aspect ratio of the resin piece is preferably 5 or more, more preferably 6 or more, and further preferably 7 or more. The upper limit of the aspect ratio of the resin pieces is not particularly limited, but is preferably 30 or less, more preferably 20 or less, still more preferably 15 or less, from the viewpoint of suppressing entanglement between the resin pieces at the time of weighing and charging.
In the present specification, the aspect ratio represents the ratio of the length of the longest side in the xy direction to the thickness in the z direction (the length of the longest side in the xy direction / the thickness in the z direction) when the resin piece is allowed to stand still. .. For the aspect ratio, the length and thickness of the longest side of about 10 to 20 resin pieces are measured, the ratio of (the length of the longest side in the xy direction / the thickness in the z direction) is obtained, and the average value is calculated. Obtained by calculation.

The length of the longest side of the resin piece in the xy direction is preferably 0.2 to 5 mm. When the length of the longest side of the resin piece in the xy direction is within the above range, the aromatic hydrocarbon-based resin can be dissolved in the solvent in a shorter time, and the productivity of the inorganic-organic composite film can be further improved. Can be improved. The length of the longest side of the resin piece in the xy direction is preferably 0.2 to 4 mm, more preferably 0.2 to 3 mm.
The length of the longest side in the xy direction can be measured by reading the scale in the scope with an optical microscope (microscope "model number PEAK2034-20" manufactured by Tokai Sangyo Co., Ltd., magnification 20 times).
The thickness of the resin piece in the z direction is preferably 0.05 to 2 mm, more preferably 0.1 to 1.5 mm, and even more preferably 0.2 to 1.0 mm.
The thickness of the resin piece in the z direction can be measured with a micrometer.

Examples of the aromatic hydrocarbon resin include polyethylene terephthalate, polybutylene terephthalate, polybutylene naphthalate, polystyrene, polysulfone, polyethersulfone, polyphenylene sulfide, polyphenylsulfone, polyallylate, polyetherimide, polyimide, and polyamideimide. And so on.
Among them, at least selected from the group consisting of polysulfone, polyethersulfone, and polyphenylsulfone in that when the above-mentioned inorganic organic composite film is used as a diaphragm for alkaline water electrolysis, excellent alkali resistance can be imparted. One is preferred, and polysulfone is more preferred in that it further facilitates the production of the inorganic-organic composite film.
The above aromatic hydrocarbon resin may be used alone or in combination of two or more.

The content of the aromatic hydrocarbon-based resin is preferably 3 to 22% by mass, more preferably 4 to 19% by mass, and further preferably 5 to 17% by mass in the resin composition.

The mass ratio of the metal (water) oxide particles to the aromatic hydrocarbon-based resin in the above resin composition is not particularly limited as long as an inorganic-organic composite film having the desired performance can be obtained, but the above-mentioned metal (water) oxidation The amount is preferably 20 to 40 parts by mass, more preferably 22 to 38 parts by mass, and further preferably 25 to 35 parts by mass with respect to 100 parts by mass of the particles. ..

(solvent)
The solvent used in the present invention is not particularly limited as long as it is a solvent capable of dissolving the above aromatic hydrocarbon resin, and for example, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, Examples thereof include N-dimethylformamide and dimethyl sulfoxide. These solvents may be used alone or in combination of two or more. Among them, it is preferable to contain N-methyl-2-pyrrolidone in that the dispersibility of the metal (water) oxide is further improved.

The content of the solvent is preferably 50 to 90% by mass, more preferably 60 to 85% by mass, and further preferably 70 to 80% by mass in the resin composition.

(Other ingredients)
The resin composition may contain other components in addition to the above-mentioned metal (water) oxide particles, aromatic hydrocarbon-based resin, and solvent. Examples of the other components include dispersants such as polyvinylpyrrolidone. These are generally known ones and can be appropriately selected and used. Further, the resin composition may contain a solvent other than the above-mentioned solvent as long as it does not affect the effect of the present invention.

(Preparation of resin composition)
The above-mentioned resin composition is prepared by mixing the above-mentioned metal (water) oxide particles, a resin piece of an aromatic hydrocarbon-based resin, and if necessary, other components together with the above-mentioned solvent. It is preferably prepared by mixing and dispersing a metal (water) oxide particle, an aromatic hydrocarbon resin (resin piece), and a solvent. The method of mixing and dispersing is not particularly limited, and known mixing and dispersing means such as a method using a mixer, a ball mill, a jet mill, a dispenser, a sand mill, a roll mill, a pot mill, a paint shaker and the like can be applied.

When preparing the resin composition, first, a solution (slurry) in which the metal (water) oxide particles are dispersed in a solvent (hereinafter, also referred to as “solution (a)”) is prepared. , The resin composition may be obtained by mixing the resin piece of the aromatic hydrocarbon resin with this solution (a). Further, a solution (a) and a solution in which a resin piece of the aromatic hydrocarbon resin is dissolved in a solvent (hereinafter, also referred to as “solution (b)”) are prepared, and these solutions are prepared. The above resin composition may be obtained by mixing. In particular, the solution (a) and the solution (b) are prepared and mixed to obtain the above resin composition because the aromatic hydrocarbon resin can be dissolved in the solvent in a shorter time. It is preferable to obtain it.

The concentration of the metal (water) oxide particles in the solution (a) is preferably 20 to 70% by mass, more preferably 30 to 60% by mass, and further preferably 40 to 50% by mass.
The concentration of the aromatic hydrocarbon resin in the solution (b) is preferably 20 to 40% by mass, more preferably 22 to 38% by mass, and further preferably 25 to 35% by mass.
The solvent used for the solution (a) and the solution (b) may be the same solvent or a different solvent as long as it contains the above-mentioned solvent, but the above-mentioned metal (water) oxide particles and the above-mentioned The same solvent is preferable in that the aromatic hydrocarbon-based resin can be more uniformly dispersed and mixed.

The addition amounts of the solution (a) and the solution (b) are appropriately adjusted so that the contents of the metal (water) oxide particles and the aromatic hydrocarbon-based resin in the above-mentioned resin composition are within a desired range. And mix.

(2) Film formation step In the production method of the present invention, a film is then formed using the resin composition obtained in the above mixing step (1).
The method for forming a film using the resin composition is not particularly limited, and a known method may be used. For example, the resin composition is applied onto a substrate to form a coating film, and the solvent is removed. Then, a method of forming an inorganic-organic composite film can be mentioned. Among them, it is preferable to include the following steps (2-1) and (2-2) in that a porous inorganic-organic composite film applicable to an alkaline water electrolysis diaphragm can be produced.
(2-1) Step of forming a coating film of the resin composition (2-2) Step of solidifying the coating film by bringing the coating film into contact with water.

As described above, when the step of forming the film in the film forming step includes a step of forming a coating film of the resin composition and a step of solidifying the coating film by contacting the coating film with water. Is also one of the preferred embodiments in the method for producing an inorganic-organic composite film of the present invention.

(2-1) Step of Forming a Coating Film of a Resin Composition As a method of forming a coating film of the resin composition obtained in the above mixing step, for example, a method of applying the above resin composition on a substrate or a method of applying the above resin composition onto a substrate is used. , A method of immersing the base material in the above resin composition and the like can be mentioned. Among them, the method of applying the above resin composition on the substrate is preferable because the coating film can be easily formed.

The method of applying the resin composition onto the substrate is not particularly limited, and known coating means such as a method using die coating, spin coating, gravure coating, curtain coating, spray, applicator, coater, etc. are applied. be able to.

The base material is not particularly limited as long as it can form a coating film of the resin composition, and for example, polytetraethylene terephthalate, polyethylene naphthalate, polypropylene, polyethylene, polyvinyl chloride, and polyvinyl acetal. , A film or sheet made of a resin such as polymethyl methacrylate and polycarbonate, a glass plate and the like.

In the case of producing an inorganic-organic composite in which an inorganic-organic composite film and a support are integrated in order to improve the strength of the obtained inorganic-organic composite film, the resin composition is applied onto the base material and then applied. By placing the support on the coating liquid and impregnating the support with the coating liquid, a coating film in which the support and the resin composition are composite may be formed.
When the inorganic-organic composite film is produced as a diaphragm for alkaline water electrolysis, it is preferable to include such a step of combining the support with the resin composition.
As the support, it is preferable to use a porous sheet-shaped member.

The material of the support can be appropriately selected depending on the purpose and application, and for example, polyethylene, polypropylene, polysulfone, polyethersulfone, polyphenylsulfone, polyphenylene sulfide, polyketone, polyimide, polyetherimide, and fluorine. Examples thereof include resins such as polysulfone. These may be used alone or in combination of two or more.

Examples of the form of the support include non-woven fabrics, woven fabrics, meshes, porous membranes, mixed fabrics of non-woven fabrics and woven fabrics, and the like, preferably non-woven fabrics, woven fabrics, or meshes.

The thickness of the support can be appropriately designed according to the purpose and application. For example, when it is produced as a diaphragm for alkaline water electrolysis, it is preferably 30 to 300 μm, more preferably 50 to 250 μm, and further preferably 100. It is ~ 200 μm.

The coating amount of the resin composition is not particularly limited, and may be appropriately set so that the inorganic-organic composite film has a thickness capable of exhibiting the desired performance. For example, in the case of producing a diaphragm for alkaline water electrolysis as the inorganic-organic composite film, the coating amount of the resin composition is usually 0.1 to 1.0 kg / m ² , preferably 0.2 to 0.8 kg / m 2. It is m ^2.

(2-2) Step of solidifying the coating film by bringing the coating film into contact with water By bringing water into contact with the coating film formed in the step (2-1), water diffuses into the coating film. However, the aromatic hydrocarbon-based resin that does not dissolve in water solidifies. On the other hand, the solvent in the coating film that can be dissolved in water elutes from the coating film. When such phase separation occurs, the aromatic hydrocarbon-based resin solidifies, and a film having pores in which a metal (water) oxide is dispersed is formed.
Examples of the method of bringing the coating film into contact with water include a method of immersing the coating film in water.

As the water, distilled water and ion-exchanged water are preferable, and ion-exchanged water is more preferable. Further, the solvent in the resin composition may be present in water in an amount of 50% or less.

The amount of water used is preferably 50 to 10000% by mass, more preferably 50% by mass, based on 100% by mass of the coating film, that is, 100% by mass of the solid content of the resin composition used for forming the coating film. Is 100 to 5000% by mass, more preferably 200 to 1000% by mass.

After solidifying the coating film in the above step (2-2), it is preferable to have a step (2-3) of further drying the solidified coating film.
By drying the coating film solidified in the above step to remove water, an inorganic organic composite film in which a metal (water) oxide is dispersed can be obtained.
The drying temperature is preferably 60 to 80 ° C.
The drying time is preferably 2 to 120 minutes, more preferably 5 to 60 minutes, still more preferably 10 to 30 minutes.
The solidified coating film is preferably dried after removing the base material.

Through the above steps, the metal (water) oxide can be uniformly dispersed, and an inorganic-organic composite film capable of fully exhibiting its performance can be obtained.
The inorganic-organic composite film obtained by the production method of the present invention will be described below.

(Inorganic organic composite membrane)
The inorganic-organic composite film obtained by the production method of the present invention contains the above-mentioned metal (water) oxide and the above-mentioned aromatic hydrocarbon-based resin.
The content of the metal (water) oxide and the aromatic hydrocarbon resin can be appropriately designed according to the purpose and application of the inorganic organic composite film, and for example, the content of the metal (water) oxide. Is usually 30 to 90% by mass, preferably 32 to 85% by mass, and more preferably 35 to 80% by mass with respect to 100% by mass of the inorganic-organic composite film. The content of the aromatic hydrocarbon resin is usually 5 to 40% by mass, preferably 7 to 35% by mass, and more preferably 10 to 30% by mass.

The inorganic-organic composite membrane is preferably a microporous membrane.
The inorganic-organic composite film preferably has a porosity of 20 to 80%, more preferably 25 to 75%, and even more preferably 30 to 70%. When the porosity is within the above range, for example, when the inorganic-organic composite membrane is used as a diaphragm for alkaline water electrolysis, the ion transmittance can be excellent.
The porosity can be determined by immersing the inorganic-organic composite film in a solution at room temperature for 24 hours and measuring the mass of the diaphragm before and after absorbing the liquid. Specifically, it is calculated by the following formula.
Porosity (% by volume) = (mass of membrane after immersion-mass of membrane before immersion) / density of solution / volume of membrane x 100
Examples of the solution include an electrolytic solution such as an alkaline aqueous solution in which an electrolyte such as potassium hydroxide or sodium hydroxide is dissolved in water.

The thickness of the inorganic-organic composite film can be appropriately designed according to the use of the inorganic-organic composite film, but is usually 10 to 3000 μm, preferably 50 to 1000 μm. For example, when the inorganic-organic composite membrane is applied to a diaphragm for alkaline water electrolysis, the thickness of the inorganic-organic composite membrane is preferably 50 to 1000 μm, preferably 100 to 500 μm, from the viewpoint of gas barrier property, ion permeability, and strength. It is more preferably 200 to 400 μm, and even more preferably 200 to 400 μm. When the inorganic-organic composite film is applied to a diaphragm for an aqueous battery, the thickness of the inorganic-organic composite film is preferably 10 to 1000 μm, more preferably 20 to 500 μm.

As described above, the method for producing an inorganic-organic composite film of the present invention can efficiently produce an inorganic-organic composite film in a short time. The production method of the present invention can be suitably applied as a method for producing an inorganic organic composite film used for various purposes such as a diaphragm for alkaline water electrolysis, a lithium ion battery separator, and a separator for an alkaline fuel cell. Above all, the production method of the present invention is suitable as a method for producing a diaphragm for alkaline water electrolysis.

(Septum for alkaline water electrolysis)
As a preferable example of the inorganic-organic composite membrane obtained by the production method of the present invention, a diaphragm for alkaline water electrolysis will be described.
The alkaline water electrolysis diaphragm may be composed of only the inorganic-organic composite film, or may have the inorganic-organic composite film formed on one or both sides of the support, or the support. It may be an inorganic-organic composite in which the above-mentioned inorganic-organic composite film is integrated with the above-mentioned inorganic-organic composite film. Above all, the above-mentioned inorganic-organic composite is preferable in that the strength and toughness of the diaphragm for alkaline water electrolysis can be further improved.

Examples of the support include those described above, and among them, a non-woven fabric, a woven fabric, or a mesh containing at least one resin selected from the group consisting of polypropylene, polyethylene, and polyphenylene sulfide. preferable.

The alkaline water electrolysis diaphragm preferably has a porosity of 20 to 80% by volume, and more preferably 25 to 75% by volume. When the porosity is within the above range, a film having excellent ion permeability and gas barrier properties can be obtained. The porosity can be determined by the method described above.

The thickness of the diaphragm for alkaline water electrolysis is preferably 50 to 1000 μm, more preferably 100 to 500 μm, and even more preferably 200 to 400 μm from the viewpoint of gas barrier property, ion permeability, and strength. ..

The diaphragm for alkaline water electrolysis is used as a member of the alkaline water electrolyzer. Examples of the alkaline water electrolyzer include an anode, a cathode, and a diaphragm for alkaline water electrolysis arranged between the anode and the cathode. More specifically, the alkaline water electrolyzer has an anode chamber in which an anode is present and a cathode chamber in which a cathode is present, which are separated by the alkaline water electrolysis diaphragm.
Examples of the anode and the cathode include known electrodes including a conductive substrate containing nickel or a nickel alloy or the like.

The method of electrolyzing water using the alkaline water electrolyzer provided with the alkaline water electrolyzing diaphragm is not particularly limited, and a known method can be used. For example, it can be performed by filling the alkaline water electrolyzer equipped with the alkaline water electrolyzing diaphragm of the present invention described above with an electrolytic solution and applying an electric current in the electrolytic solution.

As the electrolytic solution, an alkaline aqueous solution in which an electrolyte such as potassium hydroxide or sodium hydroxide is dissolved is used. The concentration of the electrolyte in the electrolytic solution is not particularly limited, but is preferably 20 to 40% by mass in that the electrolytic efficiency can be further improved.
The temperature at the time of electrolysis is preferably 50 to 120 ° C., more preferably 80 to 90 ° C., in that the ion conductivity of the electrolytic solution can be further improved and the electrolytic efficiency can be further improved. The current can be applied under known conditions and methods.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "part" means "part by mass" and "%" means "% by mass".

<Example 1>
Preparation of Inorganic Organic Composite Membrane (1. Preparation of Magnesium Hydroxide Dispersium)
Magnesium hydroxide (manufactured by Kyowa Chemical Industry Co., Ltd., product number 200-06H, average particle size 0.54 μm) and N-methyl-2-pyrrolidone (manufactured by Wako Pure Chemical Industries, Ltd.) are mixed so as to have a mass ratio of 1: 1. A magnesium hydroxide dispersion was prepared by performing a dispersion treatment at room temperature for 6 hours in a pot mill containing zirconia media balls.

(2. Preparation of polysulfone resin solution)
90 powdered polysulfone resin (manufactured by YOUJU New Material, product number PARYLS PSU, arithmetic average surface roughness Ra: 48 μm, bulk density: 0.33 g / cm ³ , aspect ratio: 5.8) at a concentration of 30% by mass. A polysulfone resin solution was prepared by thermally dissolving it in N-methyl-2-pyrrolidone (manufactured by Wako Pure Chemical Industries, Ltd.) at ° C. When preparing a 2 kg solution having the above resin concentration, N-methyl-2-pyrrolidone is first put into a 3 L separable flask, the temperature is adjusted to 90 ° C., and then the resin powder is continuously put into the blade diameter. / It was dissolved by stirring at 200 rpm with a paddle blade having a tank diameter of 0.7. The time required to dissolve the resin was 30 minutes.

(3. Preparation of coating liquid)
The magnesium hydroxide dispersion and the polysulfone resin solution obtained above are weighed so that the polysulfone resin (PSU) is 33 parts by mass with respect to 100 parts by mass of magnesium hydroxide. , Part number Awatori Rentaro ARE-500) at room temperature at 1000 rpm for about 10 minutes. The obtained mixed liquid was filtered through a 200 mesh of SUS to obtain a coating liquid.

(4. Formation of coating film)
A coating liquid is applied to a polyethylene terephthalate (PET) film with an applicator so that the thickness of the diaphragm after drying is 300 μm in total, and a polypropylene non-woven fabric (manufactured by Japan Vilene Co., Ltd., product number OA16728F, thickness 120 μm) is applied thereto. By contacting the non-woven fabric, the coating liquid was completely impregnated. Then, the nonwoven fabric impregnated with the coating liquid was bathed in water at room temperature for 10 minutes to solidify the coating liquid to form a film, and the film was peeled off from the PET film together with the nonwoven fabric in water. After bathing in water, the obtained membrane was dried at 80 ° C. for 30 minutes in a dryer to obtain an inorganic organic composite membrane (1) composed of a composite of a non-woven fabric and a membrane containing magnesium hydroxide and polysulfone resin.

<Example 2>
In Example 1 (2. Preparation of polysulfone resin solution), instead of powdered polysulfone resin, powdered polyethersulfone resin (manufactured by YOUJU New Material, product number PARYLS PES, arithmetic average surface roughness Ra: 31 μm). The inorganic-organic composite film (2) was produced by the same method as in Example 1 except that the bulk density: 0.43 g / cm ^{3 and the aspect ratio: 5.1) were used.} When preparing a 2 kg solution having the above resin concentration, the time required for dissolution was 60 minutes.

<Example 3>
In Example 1 (2. Preparation of polysulfone resin solution), instead of powdered polysulfone resin, powdered polyphenylsulfone resin (manufactured by YOUJU New Material, product number PARYLS PPS, arithmetic average surface roughness Ra: 57 μm). The inorganic-organic composite film (3) was produced by the same method as in Example 1 except that the bulk density: 0.28 g / cm ^{3 and the aspect ratio: 7.3) were used.} When preparing a 2 kg solution having the above resin concentration, the time required for dissolution was 80 minutes.

<Example 4>
In Example 1 (2. Preparation of polysulfone resin solution), a mixture of powdered polysulfone resin and polyphenylsulfone resin (manufactured by YOUJU New Material, product number PARYLS mPPSU, arithmetic average) instead of the powdered polysulfone resin. The inorganic-organic composite film (4) was produced by the same method as in Example 1 except that surface roughness Ra: 50 μm, bulk density: 0.29 g / cm ^{3, and aspect ratio: 6.6) were used.} .. When preparing a 2 kg solution having the above resin concentration, the time required for dissolution was 60 minutes.
The inorganic-organic composite films (1) to (4) produced in Examples 1 to 4 were produced for the purpose of being used as a diaphragm for alkaline water electrolysis.

<Comparative Example 1>
In Example 1 (2. Preparation of polysulfone resin solution), instead of powdered polysulfone resin, pelleted polysulfone resin (manufactured by BASF, product number Ultrazone S3010, arithmetic average surface roughness Ra: 13 μm, bulk density). The inorganic-organic composite film (c1) was prepared by the same method as in Example 1 except that: 0.82 g / cm ^{3, aspect ratio: 1.5) was used.} When preparing an eluent having a resin concentration of 2 kg, the time required for dissolution was 360 minutes.

<Comparative Example 2>
In Example 1 (2. Preparation of polysulfone resin solution), instead of the powdered polysulfone resin, pellets of polyethersulfone resin (manufactured by BASF, product number Ultrazone E3010, arithmetic average surface roughness Ra: 13 μm, The inorganic-organic composite film (c2) was produced by the same method as in Example 1 except that the bulk density: 0.85 g / cm ^{3 and the aspect ratio: 1.4) were used.} When preparing a 2 kg solution having the above resin concentration, the time required for dissolution was 480 minutes.

<Comparative Example 3>
In Example 1 (2. Preparation of polysulfone resin solution), instead of powdered polysulfone resin, pelleted polyphenylsulfone resin (manufactured by BASF, product number Ultrazone P3010, arithmetic average surface roughness Ra: 17 μm, The inorganic-organic composite film (c3) was produced by the same method as in Example 1 except that bulk density: 0.84 g / cm ^{3, aspect ratio: 1.6) was used.} When preparing a 2 kg solution having the above resin concentration, the time required for dissolution was 600 minutes.

Claims (5)

A method for producing an inorganic-organic composite film containing metal oxide particles and / or metal hydroxide particles and an aromatic hydrocarbon-based resin.
The production method includes a step of mixing metal oxide particles and / or metal hydroxide particles, a resin piece of an aromatic hydrocarbon-based resin, and a solvent to obtain a resin composition, and using the resin composition. Including the step of forming a film
Arithmetic average surface roughness of the resin piece (Ra) is Ri der than 20 [mu] m,
The bulk density of the resin piece is 0.1 to 0.7 g / cm ³ .
The aspect ratio of the resin piece is 5 or more, and the aspect ratio is 5.
The arithmetic average surface roughness (Ra) is measured by a method according to JIS B0601-2001, and is an average value when observing 10 fields of 500 μm square with respect to the resin piece.
The bulk density is a value measured using a bulk density measuring device (KAM-01 manufactured by AS ONE Corporation).
For the aspect ratio, the length of the longest side in the xy direction and the thickness in the z direction of 10 to 20 resin pieces are measured, and the ratio of (the length of the longest side in the xy direction / the thickness in the z direction) is obtained. It is the value calculated from the average value.
The length of the longest side in the xy direction is measured by reading the memory in the scope with an optical microscope, and the thickness in the z direction is measured with a micrometer.
The length of the longest side in the xy direction is 0.2 to 5 mm, and the length is 0.2 to 5 mm.
A method for producing an inorganic-organic composite film, characterized in that the thickness in the z-direction is 0.05 to 2 mm. The method for producing an inorganic-organic composite membrane according to claim 1, wherein the aromatic hydrocarbon-based resin is at least one selected from the group consisting of polysulfone, polyethersulfone, and polyphenylsulfone. The invention according to claim 1 or 2 , wherein the metal oxide particles and / or the metal hydroxide particles are at least one kind of particles selected from the group consisting of magnesium hydroxide and zirconium hydride. A method for producing an inorganic-organic composite film. The resin composition is characterized by being prepared by mixing and dispersing metal oxide particles and / or metal hydroxide particles, a resin piece of an aromatic hydrocarbon-based resin, and a solvent. 3. The method for producing an inorganic-organic composite film according to any one of 3. The step of forming the film is
A step of forming a coating film of the resin composition, and
The method for producing an inorganic-organic composite film according to any one of claims 1 to 4 , further comprising a step of solidifying the coating film by bringing the coating film into contact with water.