Ultraviolet curable resin composition, polymer electrolyte membrane, polymer electrolyte fuel cell, polymer electrolyte water electrolysis device, and method for producing polymer electrolyte membrane

Abstract

This ultraviolet curable resin composition contains: a urethane (meth)acrylate which has a weight average molecular weight of 1,500 to 20,000 inclusive and a double bond equivalent of 600 g / mol to 7,500 g / mol inclusive; a (meth)acrylate monomer which has a molecular weight of 150 to 300 inclusive; a vinyl monomer which has an acidic functional group; and a photopolymerization initiator.

Description

Ultraviolet-curable resin composition, polymer electrolyte membrane, solid polymer fuel cell, solid polymer water electrolysis device, and method for producing polymer electrolyte membrane

[0001] The present invention relates to an ultraviolet-curable resin composition, a polymer electrolyte membrane, a solid polymer fuel cell, a solid polymer water electrolysis device, and a method for producing a polymer electrolyte membrane.

[0002] Proton-conducting membranes composed solely of polymers having phosphate groups in their side chains are easily broken and have low strength. Patent Document 1 discloses an alternative proton-conducting membrane in which a polymer having phosphate groups in its side chains is polymerized within the pores of a porous membrane, thereby supporting the polymer within the pores. Proton-conducting membranes are used, for example, as polymer electrolyte membranes in solid molecular fuel cells.

[0003] Patent No. 4621344

[0004] Because the pores in the porous membrane that constitutes the proton-conducting membrane are very small, it is difficult to load a polymer into all of the pores, making it difficult to achieve excellent proton conductivity throughout the membrane.

[0005] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a polymer electrolyte membrane having excellent proton conductivity and high strength, a solid polymer fuel cell and a solid polymer water electrolysis device each including the polymer electrolyte membrane, a method for producing the polymer electrolyte membrane, and an ultraviolet-curable resin composition that can be used as a resin composition constituting the polymer electrolyte membrane.

[0006] The present invention is as follows.

[0007] [1] An ultraviolet-curable resin composition according to the present invention comprises: a urethane (meth)acrylate having a weight-average molecular weight of 1,500 or more and 20,000 or less and a double bond equivalent of 600 g / mol or more and 7,500 g / mol or less; a (meth)acrylate monomer having a molecular weight of 150 or more and 300 or less; a vinyl monomer having an acidic functional group; and a photopolymerization initiator, wherein the content of the urethane (meth)acrylate is 20% by weight or more and 45% by weight or less, based on a total of 100% by weight of the urethane (meth)acrylate, the (meth)acrylate monomer, and the vinyl monomer; and the content of the (meth)acrylate monomer is 15% by weight or more and 45% by weight or less, based on a total of 100% by weight of the urethane (meth)acrylate, the (meth)acrylate monomer, and the vinyl monomer. The content of the vinyl monomer is 20% by weight or more and 55% by weight or less, relative to 100% by weight of the total of the urethane (meth)acrylate, the (meth)acrylate monomer, and the vinyl monomer.

[0008] [2] The acidic functional group may be at least one selected from the group consisting of a carboxyl group, a phosphonic acid group, a sulfonic acid group, and a phosphoric acid group.

[0009] [3] The number of the acidic functional groups of the vinyl monomer may be one or two.

[0010] [4] A polymer electrolyte membrane according to the present invention is composed of a cured ultraviolet-curable resin composition according to any one of [1] to [3].

[0011] [5] A solid polymer fuel cell according to the present invention comprises: the polymer electrolyte membrane according to [4]; an anode catalyst layer formed on one side of the polymer electrolyte membrane; a cathode catalyst layer formed on the other side of the polymer electrolyte membrane; a first gas diffusion layer formed on the other side of the anode catalyst layer opposite to the one side on which the polymer electrolyte membrane is formed; a second gas diffusion layer formed on the other side of the cathode catalyst layer opposite to the one side on which the polymer electrolyte membrane is formed; a first separator disposed on the other side of the first gas diffusion layer opposite to the one side on which the anode catalyst layer is formed; and a second separator disposed on the other side of the second gas diffusion layer opposite to the one side on which the cathode catalyst layer is formed.

[0012] [6] A solid polymer water electrolysis device according to the present invention comprises: the polymer electrolyte membrane according to [4]; an anode catalyst layer formed on one side of the polymer electrolyte membrane; a cathode catalyst layer formed on the other side of the polymer electrolyte membrane; a first gas diffusion layer formed on the other side of the anode catalyst layer opposite to the one side on which the polymer electrolyte membrane is formed; a second gas diffusion layer formed on the other side of the cathode catalyst layer opposite to the one side on which the polymer electrolyte membrane is formed; a first separator disposed on the other side of the first gas diffusion layer opposite to the one side on which the anode catalyst layer is formed; and a second separator disposed on the other side of the second gas diffusion layer opposite to the one side on which the cathode catalyst layer is formed.

[0013] [7] A method for producing a polymer electrolyte membrane according to the present invention includes: a preparation step of preparing the ultraviolet-curable resin composition according to any one of [1] to [3]; a resin layer formation step of forming a resin layer composed of the ultraviolet-curable resin composition on one separate film; a film arrangement step of arranging another separate film on one side of the resin layer, the other side being the side on which the one separate film is arranged; a curing step of irradiating the resin layer with ultraviolet light through the one separate film or the other separate film to cure the resin layer; and a peeling step of peeling the one separate film and the other separate film from the cured resin layer.

[0014] According to the present invention, it is possible to provide a polymer electrolyte membrane having excellent proton conductivity and high strength, a solid polymer fuel cell and a solid polymer water electrolysis device each including this polymer electrolyte membrane, a method for producing a polymer electrolyte membrane, and an ultraviolet-curable resin composition that can be used as a resin composition constituting this polymer electrolyte membrane.

[0015] 1 is a schematic cross-sectional view of a polymer electrolyte membrane according to an embodiment of the present invention; FIG. 2 is a schematic cross-sectional view of a proton exchange polymer electrolyte fuel cell; FIG. 3 is a schematic cross-sectional view of a proton exchange polymer electrolyte water electrolysis device;

[0016] Hereinafter, an ultraviolet-curable resin composition, a polymer electrolyte membrane, a solid polymer fuel cell, a solid polymer water electrolysis device, and a method for producing a polymer electrolyte membrane, which are modes for carrying out the present invention (hereinafter referred to as embodiments), will be described in detail. The embodiments are examples for explaining the present invention, and are not intended to limit the present invention to the following content. The present invention can be carried out by appropriately modifying it within the scope of its gist.

[0017] In the present invention, urethane (meth)acrylate refers to urethane acrylate or urethane methacrylate. (Meth)acrylate monomer refers to acrylate monomer or methacrylate monomer. Weight refers to the weight of the resin alone, excluding volatile components such as organic solvents contained in the resin, or the weight of the non-volatile components.

[0018] [UV-Curable Resin Composition] The UV-curable resin composition according to an embodiment includes a urethane (meth)acrylate, a (meth)acrylate monomer, a vinyl monomer, and a photopolymerization initiator. Such a UV-curable resin composition can be suitably used as a resin composition for forming a polymer electrolyte membrane having excellent proton conductivity and high strength.

[0019] Components contained in the ultraviolet-curable resin composition of the embodiment will be described below.

[0020] (Urethane (meth)acrylate) Examples of the urethane (meth)acrylate used in the embodiment include addition type urethane (meth)acrylate, polycarbonate-based urethane (meth)acrylate, and polyester-based urethane (meth)acrylate. From the viewpoint of obtaining a polymer electrolyte membrane having excellent proton conductivity and high strength, the urethane (meth)acrylate is preferably addition type urethane (meth)acrylate or polycarbonate-based urethane (meth)acrylate. The urethane (meth)acrylate may be used alone or in combination of two or more types. The addition type urethane (meth)acrylate is also called adduct-based urethane (meth)acrylate.

[0021] From the viewpoint of obtaining a polymer electrolyte membrane having high strength, the weight average molecular weight of the urethane (meth)acrylate is from 1,500 to 20,000, preferably from 1,500 to 15,000, more preferably from 1,700 to 15,000, and even more preferably from 5,000 to 15,000. The weight average molecular weight of the hydroxy (meth)acrylate can be determined by gel permeation chromatography (GPC) using standard polymethyl methacrylate.

[0022] From the viewpoint of obtaining a polymer electrolyte membrane having excellent proton conductivity and high strength, the double bond equivalent of the urethane (meth)acrylate is 600 g / mol to 7500 g / mol, preferably 750 g / mol to 7500 g / mol, more preferably 800 g / mol to 7500 g / mol, and even more preferably 800 g / mol to 2500 g / mol. The urethane (meth)acrylate may have double bonds in the side chain and / or at the terminal, and from the viewpoint of increasing reactivity, it is preferable to have double bonds in both the side chain and the terminal. The double bond equivalent can be calculated from the formula: double bond equivalent (g / mol) = weight average molecular weight of monomer / number of polymerizable double bonds in the same molecule (mol).

[0023] The addition-type urethane (meth)acrylate described above can be obtained, for example, by reacting a hydroxy(meth)acrylate with a diisocyanate. Examples of the hydroxy(meth)acrylate include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and caprolactone-modified 2-hydroxyethyl (meth)acrylate. Furthermore, from the viewpoint of easy availability, 2-hydroxyethyl (meth)acrylate and 2-hydroxypropyl (meth)acrylate are preferred as the hydroxy(meth)acrylate. Examples of diisocyanates include (i) aromatic diisocyanates such as tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylene diisocyanate, and naphthalene diisocyanate; (ii) aliphatic diisocyanates such as hexamethylene diisocyanate and trimethylhexamethylene diisocyanate; and (iii) alicyclic diisocyanates such as isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, norbornene diisocyanate, and hydrogenated xylene diisocyanate. In view of ease of availability, tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, and hexamethylene diisocyanate are preferred.

[0024] The polycarbonate-based urethane (meth)acrylate can be obtained by reacting, for example, a polycarbonate diol with a hydroxy (meth)acrylate and a diisocyanate. Examples of the polycarbonate diol include propylene carbonate diol, hexamethylene carbonate diol, and 3-methylpentene carbonate diol. From the viewpoint of reactivity, the polycarbonate diol is preferably propylene carbonate diol or hexamethylene carbonate diol.

[0025] The polyester-based urethane (meth)acrylate can be obtained, for example, by reacting polyester polyol, hydroxy (meth)acrylate, and diisocyanate.

[0026] Examples of polyester polyols include reaction products of an alcohol component and an acid component. Examples of the alcohol component include ethylene glycol, propylene glycol, butanediol, 1,6-hexanediol, 2-methyl-1,8-octanediol, nonanediol, cyclohexanedimethanol, neopentyl glycol, 3-methyl-1,5-pentanediol, and hydroxypivalic acid neopentyl glycol ester. From the viewpoint of reactivity, the alcohol component is preferably ethylene glycol, propylene glycol, butanediol, 1,6-hexanediol, 2-methyl-1,8-octanediol, nonanediol, or cyclohexanedimethanol.

[0027] Examples of the acid component include dibasic acids such as adipic acid, sebacic acid, succinic acid, maleic acid, phthalic acid, hexahydrophthalic acid, and terephthalic acid, or anhydrides thereof, or ring-opening reaction products of polycarbonate diol and caprolactone, etc. From the viewpoint of efficiently promoting condensation polymerization, the acid component is preferably adipic acid or phthalic acid.

[0028] The content of the urethane (meth)acrylate in the ultraviolet-curable resin composition is 20% by weight or more and 45% by weight or less, and preferably 25% by weight or more and 40% by weight or less, relative to 100% by weight of the total of the urethane (meth)acrylate, the (meth)acrylate monomer, and the vinyl monomer. When the ultraviolet-curable resin composition contains the urethane (meth)acrylate in the above-mentioned proportion, the strength of the polymer electrolyte membrane is improved without deteriorating the proton conductivity performance.

[0029] ((Meth)acrylate Monomer) Examples of the (meth)acrylate monomer used in the embodiment include butyl (meth)acrylate, stearyl (meth)acrylate, benzyl (meth)acrylate, phenoxyethyl (meth)acrylate, diethylene glycol di(meth)acrylate, etc. Furthermore, from the viewpoint of compatibility with other materials constituting the ultraviolet-curable resin composition, benzyl (meth)acrylate, phenoxyethyl (meth)acrylate, and diethylene glycol di(meth)acrylate are more preferred as the (meth)acrylate monomer.

[0030] From the viewpoint of diluting the urethane (meth)acrylate, the vinyl monomer, and the photopolymerization initiator with the (meth)acrylate monomer, the molecular weight of the (meth)acrylate monomer is, for example, 150 or more and 300 or less, preferably 150 or more and 250 or less, and more preferably 175 or more and 225 or less.

[0031] From the viewpoint of reducing the viscosity of the UV-curable resin composition, the content of the (meth)acrylate monomer contained in the UV-curable resin composition is 15% by weight or more and 45% by weight or less, and preferably 15% by weight or more and 40% by weight or less, relative to 100% by weight of the total of the urethane (meth)acrylate, the (meth)acrylate monomer, and the vinyl monomer. This allows the vinyl monomer having an acidic functional group that affects proton conductivity to be uniformly dispersed in the UV-curable resin composition. By curing the UV-curable resin composition with this vinyl monomer uniformly dispersed, a polymer electrolyte membrane is obtained in which the acidic functional group is present in the thickness direction of the membrane and on the entire main surface of the membrane. Such a polymer electrolyte membrane has excellent proton conductivity throughout the membrane.

[0032] (Vinyl Monomer) The vinyl monomer has an acidic functional group. Examples of vinyl monomers having an acidic functional group include monofunctional phosphate (meth)acrylate (2-methacryloyloxyethyl acid phosphate), monofunctional sulfonic acid (meth)acrylate (2-[methacryloyloxy]ethanesulfonic acid), phosphonic acid (meth)acrylate, phosphonic acid di(meth)acrylate (bis[2-(methacryloyloxyethyl)]phosphate), vinylphosphonic acid, and vinylsulfonic acid. From the viewpoint of storage stability, the vinyl monomer is preferably monofunctional phosphate (meth)acrylate (2-methacryloyloxyethyl acid phosphate), monofunctional sulfonic acid (meth)acrylate (2-[methacryloyloxy]ethanesulfonic acid), phosphonic acid di(meth)acrylate, vinylphosphonic acid, or vinylsulfonic acid.

[0033] The acidic functional group is composed of at least one selected from the group consisting of a carboxy group, a phosphonic acid group, a sulfonic acid group, and a phosphate group. From the viewpoint of obtaining a polymer electrolyte membrane having excellent proton conductivity, the acidic functional group is preferably a phosphonic acid, sulfonic acid, and / or phosphate group. From the viewpoint of obtaining a polymer electrolyte membrane having excellent proton conductivity, the number of acidic functional groups in the vinyl monomer is preferably 1 or 2. Examples of vinyl monomers having phosphonic acid, sulfonic acid, and / or phosphoric acid include vinyl phosphonic acid, vinyl sulfonic acid, monofunctional phosphate (meth)acrylate (2-methacryloyloxyethyl acid phosphate), monofunctional sulfonic acid (meth)acrylate (2-[methacryloyloxy]ethanesulfonic acid), and the like.

[0034] From the viewpoint of obtaining a polymer electrolyte membrane having excellent proton conductivity, the molecular weight of the vinyl monomer is, for example, 100 or more and 1,000 or less, preferably 100 or more and 700 or less, and more preferably 100 or more and 400 or less.

[0035] The content of the vinyl monomer contained in the ultraviolet-curable resin composition is 20% by weight or more and 55% by weight or less, and preferably 20% by weight or more and 50% by weight or less, relative to 100% by weight of the total of the urethane (meth)acrylate, the (meth)acrylate monomer, and the vinyl monomer. A polymer electrolyte membrane obtained by curing such an ultraviolet-curable resin composition has excellent proton conductivity.

[0036] (Photopolymerization initiator) Examples of the photopolymerization initiator include short wavelength absorption photopolymerization initiators that absorb light with a wavelength of less than 400 nm, and long wavelength absorption photopolymerization initiators that absorb light with a wavelength of 400 nm or more. Examples of the short wavelength absorption photopolymerization initiator include Omnirad 2959, Omnirad 651, Omnirad 379, and Omnirad 907, all of which are manufactured by IGM RESIN. Examples of the long wavelength absorption photopolymerization initiator include Omnirad 184, Omnirad TPO, Omnirad 819, and Omnirad EMK, all of which are manufactured by IGM RESIN.

[0037] The photopolymerization initiator is preferably a long-wavelength absorbing photopolymerization initiator from the viewpoint of uniformly curing the UV-curable resin composition in the thickness direction of the polymer electrolyte membrane composed of the UV-curable resin composition. One type of photopolymerization initiator may be used alone, or two or more types may be used in combination. From the viewpoint of promoting the photocuring reaction, the content of the photopolymerization initiator is preferably 1 wt% to 10 wt%, more preferably 1 wt% to 7 wt%, and even more preferably 1 wt% to 3 wt%, relative to 100 wt% of the total of the urethane (meth)acrylate, the (meth)acrylate monomer, and the vinyl monomer.

[0038] (Other Components) Additives may be added to the ultraviolet-curable resin composition of the embodiment within a range that does not impair the proton conductivity and strength of the polymer electrolyte membrane. Examples of additives include chain transfer agents, sensitizers, dispersants, softeners, heat aging inhibitors, and silane coupling agents.

[0039] The ultraviolet-curable resin composition of the embodiment can be obtained by mixing predetermined amounts of the above-described materials in a container.

[0040] [Polymer Electrolyte Membrane] Next, the configuration of the polymer electrolyte membrane of the embodiment will be described. The polymer electrolyte membrane 40 of the embodiment shown in Figure 1 is made of the ultraviolet-curable resin composition of the embodiment. From the viewpoint of handleability and maintaining the strength of the membrane, the thickness of the polymer electrolyte membrane 40 of the embodiment is, for example, 10 μm or more and 300 μm or less, and more preferably 50 μm or more and 200 μm or less.

[0041] The polymer electrolyte membrane 40 can be obtained, for example, by the following procedure. A urethane (meth)acrylate, a (meth)acrylate monomer, a vinyl monomer, and a photopolymerization initiator are mixed in the amounts described above in a container to prepare an ultraviolet-curable resin composition (preparation step). The obtained ultraviolet-curable resin composition is applied to a first separate film using, for example, a coating device to form a resin layer composed of the ultraviolet-curable resin composition (resin layer formation step). Next, a second separate film is placed on the surface of the formed resin layer (film placement step). The resin layer is irradiated with ultraviolet light through the first separate film or the second separate film to harden the resin layer (hardening step). The first separate film and the second separate film placed on both sides of the resin layer are peeled off (peeling step) to obtain the resin layer, i.e., the polymer electrolyte membrane 40.

[0042] Examples of coating devices used in the resin layer forming step include a die coater and a comma coater. The wavelength of the ultraviolet light irradiated onto the resin layer in the curing step is, for example, 200 nm or more and 800 nm or less. The integrated light amount of the ultraviolet light irradiated onto the resin layer is, for example, 1000 mJ / cm. ２ More than 10000mJ / cm ２ From the viewpoint of uniformly curing the ultraviolet-curable resin composition constituting the resin layer in the thickness direction of the resin layer, the wavelength of the ultraviolet light is preferably 400 nm or more and 800 nm or less. Furthermore, when irradiating the ultraviolet-curable resin composition with ultraviolet light of 400 nm or more and 800 nm or less, the photopolymerization initiator contained in the ultraviolet-curable resin composition is preferably Omnirad 819 or Omnirad EMK, which absorbs ultraviolet light with a wavelength of 400 nm or more.

[0043] The thickness of the first and second separate films used in the resin layer forming process and the film disposing process is, for example, 25 μm to 100 μm, preferably 75 μm to 100 μm, from the viewpoint of facilitating the disposing and peeling of the separate films. Examples of materials for the separate films include polyethylene, polypropylene, polyimide, polyamide, polyethylene naphthalate, and polyethylene terephthalate. From the viewpoint of efficiently irradiating the resin layer with ultraviolet light in the curing process, the separate film is preferably a colorless and transparent film. Furthermore, from the viewpoint of facilitating the peeling of the separate film from the resin layer, a release treatment may be applied to the surface of the separate film. Examples of treatment agents for the release treatment include silicone-based treatment agents and fluorine-based treatment agents.

[0044] In the resin layer forming step, the formed resin layer may be heated. This hardens the resin layer, so that the thickness of the resin layer is less likely to change when a second separate film is laminated in the next step. Furthermore, although the polymer electrolyte membrane 40 of the embodiment is manufactured in the order of the resin layer forming step, the film disposing step, the curing step, and the peeling step, the polymer electrolyte membrane 40 may be obtained without performing the film disposing step. That is, the polymer electrolyte membrane 40 may be obtained by irradiating the resin layer obtained in the resin layer forming step with ultraviolet light without disposing a second separate film, performing the curing step to harden the resin layer, and then performing the peeling step.

[0045] The obtained polymer electrolyte membrane 40 can be used as a polymer electrolyte membrane for use in a polymer electrolyte fuel cell, more specifically, as a polymer electrolyte membrane for use in a proton exchange polymer electrolyte fuel cell.

[0046] The obtained polymer electrolyte membrane 40 can be used as a polymer electrolyte membrane for use in a solid polymer water electrolysis device, more specifically, as a polymer electrolyte membrane for use in a proton exchange type solid polymer water electrolysis device.

[0047] [Solid Polymer Electrolyte Fuel Cell] A proton exchange type solid polymer fuel cell 10 using the polymer electrolyte membrane 40 of the embodiment will be described as an example. As shown in Figure 2, the proton exchange type solid polymer fuel cell 10 includes an anode electrode 20, a cathode electrode 30, a polymer electrolyte membrane 40, a separator 51, and a separator 52.

[0048] The anode electrode 20 is composed of an anode catalyst layer 41 and a gas diffusion layer 43. The anode catalyst layer 41 is formed on one surface of the polymer electrolyte membrane 40. The gas diffusion layer 43 is formed on the other surface of the anode catalyst layer 41, which is the surface opposite to the surface on which the polymer electrolyte membrane 40 is formed. That is, in order from closest to the polymer electrolyte membrane 40, the anode catalyst layer 41 and the gas diffusion layer 43 are stacked on the polymer electrolyte membrane 40. The gas diffusion layer 43 corresponds to a first gas diffusion layer.

[0049] The cathode electrode 30 is composed of a cathode catalyst layer 42 and a gas diffusion layer 44. The cathode catalyst layer 42 is laminated on the other side of the polymer electrolyte membrane 40. The gas diffusion layer 44 is formed on the other side of the cathode catalyst layer 42, which is the opposite side to the side on which the polymer electrolyte membrane 40 is formed. That is, in order from closest to the polymer electrolyte membrane 40, the cathode catalyst layer 42 and the gas diffusion layer 44 are laminated on the polymer electrolyte membrane 40. The gas diffusion layer 44 corresponds to a second gas diffusion layer.

[0050] The anode catalyst layer 41 has a catalytic function that promotes the oxidation reaction of hydrogen. Examples of materials for the anode catalyst layer 41 include a carbon support with a platinum loading of 50 wt %. Specifically, TEC10E50E (manufactured by Tanaka Kikinzoku Kogyo K.K.) is used.

[0051] The cathode catalyst layer 42 has a catalytic function that promotes the reduction reaction of oxygen. Examples of materials for the cathode catalyst layer 42 include a carbon support with a platinum loading of 50 wt %. Specifically, TEC10E50E (manufactured by Tanaka Kikinzoku Kogyo K.K.) is used.

[0052] The gas diffusion layer 43 is formed by diffusing hydrogen (H ２The gas diffusion layer 44 functions to diffuse oxygen (O ２ ) 61 throughout the cathode catalyst layer 42. The gas diffusion layer 43 and the gas diffusion layer 44 may be made of carbon paper with a water-repellent surface. A specific example is SGL24-BCH (manufactured by SGL Carbon Co., Ltd.).

[0053] The polymer electrolyte membrane 40 absorbs protons (H ＋ ) 72 is passed through.

[0054] To protect the anode electrode 20, the polymer electrolyte membrane 40, and the cathode electrode 30, a pair of separators 51 and 52 are arranged to sandwich the anode electrode 20, the polymer electrolyte membrane 40, and the cathode electrode 30. The separator 51 is arranged on one side of the gas diffusion layer 43, opposite the side on which the anode catalyst layer 41 is formed. The separator 52 is arranged on the other side of the gas diffusion layer 44, opposite the side on which the cathode catalyst layer 42 is formed. As shown in FIG. 2 , the separators 51 and 52 have a plurality of grooves 53 and 54 on one side. The grooves 53 and 54 are formed on one side in parallel in a direction perpendicular to the longitudinal direction of the grooves 53 and 54. Examples of the separators 51 and 52 include metal separators manufactured by Mick Lab.

[0055] The separator 51 having grooves 53 on its surface is disposed on the gas diffusion layer 43 so that the surface on which the grooves 53 are formed is in contact with the gas diffusion layer 43. The grooves 53 are formed to allow hydrogen (H ２ ) 63, and is connected to a supply path 65 that supplies hydrogen (H ２ The groove 53 also functions to allow hydrogen (H ２ ) 63 is also connected to a discharge path 66 for discharging the same.

[0056] The separator 52 having grooves 54 on its surface is disposed on the gas diffusion layer 44 so that the surface on which the grooves 54 are formed is in contact with the gas diffusion layer 44. The grooves 54 are formed to allow oxygen (O ２) 61, and is connected to a supply channel 67 that supplies oxygen (O ２ The grooves 54 also function to allow oxygen (O ２ ) 61 and proton (H ＋ ) 72 and the water (H ２ O) 62 is also connected to a discharge path 68 for discharging the same.

[0057] The separator 51 corresponds to a first separator, and the separator 52 corresponds to a second separator.

[0058] Next, the mechanism by which the proton exchange polymer electrolyte fuel cell 10 generates electromotive force will be described.

[0059] Hydrogen (H ２ ) 63 passes through the grooves 53 of the separator 51 and reaches the anode catalyst layer 41 via the gas diffusion layer 43. ２ ) 63 is a hydrogen oxidation reaction, i.e., H ２ →2H ＋ +2e － The reaction occurs, and protons (H ＋ ) 72 and electrons (e － ) 71 is generated. The hydrogen (H ２ ) 63 are discharged to the outside of the proton exchange polymer electrolyte fuel cell 10 via a discharge path 66. － ) 71 returns to the proton exchange polymer electrolyte fuel cell 10 via the external circuit 70. At this time, an electromotive force is generated in the proton exchange polymer electrolyte fuel cell 10.

[0060] Proton (H ＋ ) 72 passes through the polymer electrolyte membrane 40 and reaches the cathode catalyst layer 42. Oxygen (O ２ ) 61 reaches the cathode catalyst layer 42 through the grooves 54 and the gas diffusion layer 44. In the cathode catalyst layer 42, oxygen (O ２ ) 61 and proton (H ＋ ) 72 by reduction reaction with water (H ２ O) 62 is generated.＋ +O ２ +4e － →2H ２ The reaction of O with water (H ２ O) 62 is discharged to the outside of the proton exchange polymer electrolyte fuel cell 10 via a discharge path 68.

[0061] The polymer electrolyte membrane 40 of the embodiment having acidic functional groups throughout the membrane absorbs protons (H ＋ ) 72 can be efficiently transferred to the cathode catalyst layer 42, resulting in excellent proton conductivity.

[0062] [Solid polymer water electrolysis device] Next, a proton exchange type solid polymer water electrolysis device 100 using the polymer electrolyte membrane 40 of the embodiment will be described as an example. As shown in Fig. 3 , the proton exchange type solid polymer water electrolysis device 100 includes an anode electrode 120, a cathode electrode 130, the polymer electrolyte membrane 40, and separators 151 and 152.

[0063] The anode electrode 120 is composed of an anode catalyst layer 141 and a gas diffusion layer 143. The anode catalyst layer 141 is formed on one surface of the polymer electrolyte membrane 40. The gas diffusion layer 143 is formed on the other surface of the anode catalyst layer 141, which is the surface opposite to the surface on which the polymer electrolyte membrane 40 is formed. That is, in order from closest to the polymer electrolyte membrane 40, the anode catalyst layer 141 and the gas diffusion layer 143 are stacked on the polymer electrolyte membrane 40. The gas diffusion layer 143 corresponds to a first gas diffusion layer.

[0064] The cathode electrode 130 is composed of a cathode catalyst layer 142 and a gas diffusion layer 144. The cathode catalyst layer 142 is formed on the other side of the polymer electrolyte membrane 40. The gas diffusion layer 144 is formed on the other side of the cathode catalyst layer 142, which is the opposite side to the side on which the polymer electrolyte membrane 40 is formed. That is, the cathode catalyst layer 142 and the gas diffusion layer 144 are stacked on the polymer electrolyte membrane 40 in order from closest to the polymer electrolyte membrane 40. The gas diffusion layer 144 corresponds to a second gas diffusion layer.

[0065] The anode catalyst layer 141 has a catalytic function that promotes the water decomposition reaction. Examples of materials for the anode catalyst layer 141 include a carbon support containing iridium oxide. Specifically, ELC-0110 (iridium content 1 mg / cm ２ ) (manufactured by Tanaka Kikinzoku Kogyo Co., Ltd.) can be mentioned.

[0066] The cathode catalyst layer 142 has a catalytic function that promotes the reduction reaction of hydrogen. Examples of materials for the cathode catalyst layer 142 include a carbon support with a platinum loading of 50 wt %. Specifically, TEC10E50E (platinum loading of 1 mg / cm ２ ) (manufactured by Tanaka Kikinzoku Kogyo Co., Ltd.) can be mentioned.

[0067] The gas diffusion layer 143 is formed by diffusing water (H ２ The gas diffusion layer 144 has a function of diffusing protons (H O) 163 generated in the water splitting reaction of the anode catalyst layer 141 in the cathode catalyst layer 142, and distributing the protons throughout the anode catalyst layer 141. ＋ ) 172 and the electrons (e － ) 171 ２ ) 161 throughout the separator 152 and efficiently guides it to the grooves 154 .

[0068] Porous titanium having excellent corrosion resistance and high strength can be used as the material for the gas diffusion layer 143. Specifically, WEBTi (registered trademark)-K (manufactured by Toho Titanium Co., Ltd.) can be used.

[0069] The gas diffusion layer 144 may be made of carbon paper with a water-repellent surface, such as SIGRACET (registered trademark) 39BC (manufactured by SLG Carbon Japan Co., Ltd.).

[0070] The polymer electrolyte membrane 40 absorbs protons (H ＋ ) 172 only.

[0071] To protect the anode electrode 120, the polymer electrolyte membrane 140, and the cathode electrode 130, a pair of separators 151 and 152 are arranged to sandwich the anode electrode 120, the polymer electrolyte membrane 140, and the cathode electrode 130. The separator 151 is arranged on one side of the gas diffusion layer 143, opposite the side on which the anode catalyst layer 141 is formed. The separator 152 is arranged on the other side of the gas diffusion layer 144, opposite the side on which the cathode catalyst layer 142 is formed. As shown in FIG. 3 , the separators 151 and 152 have multiple grooves 153 and 154 on one side. The grooves 153 and 154 are formed on one side in parallel and aligned in a direction perpendicular to the longitudinal direction of the grooves 153 and 154. An example of the separator 151 is a water electrolysis-side gold-plated titanium separator (manufactured by Miklab Co., Ltd.). The separator 152 may be, for example, a gold-plated titanium separator (manufactured by Miklab Co., Ltd.) on the hydrogen generation side.

[0072] The separator 151 having grooves 153 on its surface is disposed on the gas diffusion layer 143 so that the surface on which the grooves 153 are formed is in contact with the gas diffusion layer 143. The grooves 153 are formed to allow water (H ２ O) 163, and is connected to a supply channel 165 that supplies water (H ２ The groove 153 has a function of flowing water (H ２ O)163 and oxygen (O ２ ) 162 is also connected to a discharge path 166 that discharges the

[0073] The separator 152 having grooves 154 on its surface is disposed on the gas diffusion layer 144 so that the surface on which the grooves 154 are formed is in contact with the gas diffusion layer 144. The grooves 154 are formed to allow hydrogen (H ２ ) 161 is also connected to a discharge path 168 for discharging the same.

[0074] The separator 151 corresponds to a first separator, and the separator 152 corresponds to a second separator.

[0075] The power supply 170 supplies electricity to the proton exchange polymer water electrolysis device 100 .

[0076] Next, the mechanism by which hydrogen is generated in the proton exchange polymer water electrolysis device 100 will be described.

[0077] Water (H ２ The water (H O) 163 passes through the grooves 153 of the separator 151 and reaches the anode catalyst layer 141 via the gas diffusion layer 143. ２ O) 163 is converted into electricity (electrons (e － ) 171) is electrolyzed by this electrolysis of water, i.e., 2H ２ O → 4H ＋ +4e － +O ２ The reaction produces water (H ２ O) to proton (H ＋ ) and electrons (e － ) and oxygen (O ２ ) is generated. Unreacted water (H ２ O)163 and oxygen (O ２ ) 162 is discharged to the outside of the proton exchange type solid polymer water electrolysis apparatus 100 via a discharge path 166 .

[0078] Proton (H ＋ ) 172 passes through the polymer electrolyte membrane 40 and reaches the cathode catalyst layer 142. In the cathode catalyst layer 142, protons (H ＋ ) 172 and the electrons (e － ) 171, i.e., 2H ＋ +2e － →H2 to hydrogen (H ２ ) is generated. The generated hydrogen (H ２ ) 161 passes through the grooves 154 of the separator 152 via the gas diffusion layer 144 and is stored outside the proton exchange type solid polymer water electrolysis apparatus 100 via the discharge channel 168.

[0079] The polymer electrolyte membrane 40 of the embodiment having acidic functional groups in the membrane thickness direction and on the entire main surface of the membrane can absorb protons (H ＋) 172 can be efficiently transferred to the cathode catalyst layer 142, resulting in excellent proton conductivity.

[0080] The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples in any way.

[0081] The following materials were used as components contained in the ultraviolet-curable resin compositions of the examples and comparative examples. (Ester-based urethane (meth)acrylates) (1) CWD8E26 (manufactured by Negami Chemical Industrial Co., Ltd.) Weight average molecular weight 20,000, double bond equivalent 5,000 g / mol, glass transition temperature (Tg) -19°C, viscosity at 25°C 150,000 mPa·s, number of functional groups 4. (2) CWD11N (manufactured by Negami Chemical Industrial Co., Ltd.) Weight average molecular weight 10,500, double bond equivalent 3,500 g / mol, Tg -37°C, viscosity at 25°C 30,000 Pa·s, number of functional groups 3.

[0082] (Adduct-based urethane (meth)acrylate) (3) SMT001 (manufactured by Negami Chemical Industrial Co., Ltd.) Weight average molecular weight 1700, double bond equivalent 567 g / mol, Tg 103°C, viscosity at 25°C 1,000,000 Pa·s, viscosity at 60°C 250,000 Pa·s, number of functional groups 3. (4) UN2701 (manufactured by Negami Chemical Industrial Co., Ltd.) Weight average molecular weight 1500, double bond equivalent 750 g / mol, Tg 57°C, viscosity at 25°C 600,000 Pa·s, number of functional groups 2. (5) UN2600 (manufactured by Negami Chemical Industrial Co., Ltd.) Weight average molecular weight 1600, double bond equivalent 800 g / mol, Tg 10°C, viscosity at 25°C 10,000 Pa·s, number of functional groups 2.

[0083] (Carbonate-based urethane (meth)acrylate) (6) UN9000PEP (manufactured by Negami Chemical Industrial Co., Ltd.) Weight average molecular weight: 5000, double bond equivalent: 2500 g / mol, Tg: -7°C, viscosity at 25°C: 2,000,000 Pa·s, number of functional groups: 2. (7) UN9200 (manufactured by Negami Chemical Industrial Co., Ltd.) Weight average molecular weight: 15,000, double bond equivalent: 7500 g / mol, Tg: -27°C, viscosity at 25°C: 2,000,000 Pa·s, number of functional groups: 2.

[0084] ((Meth)acrylate Monomer) (1) Light Ester PO (manufactured by Kyoeisha Chemical Co., Ltd.) Weight average molecular weight: 201, double bond equivalent: 201 g / mol, viscosity at 25° C.: 7 Pa·s, number of functional groups: 1.

[0085] (Vinyl Monomer) Vinylphosphonic acid CAS RN 1746-03-8 (manufactured by Tokyo Chemical Industry Co., Ltd.) Weight average molecular weight: 108, double bond equivalent: 108 g / mol, number of functional groups: 1.

[0086] (Photopolymerization initiator) Omnirad 819 (manufactured by IGM Resin).

[0087] Example 1 (Preparation of UV-Curable Resin Composition) 33.3 parts by weight of Light Ester PO and 3.0 parts by weight of Omnirad 819 were added to a reaction vessel and stirred at 70°C. 33.3 parts by weight of CWD8E26 heated to 70°C was added to the reaction vessel and stirred until uniformly mixed. The mixture was then cooled to room temperature. Next, 33.3 parts by weight of CAS RN 1746-03-8 was added to the reaction vessel and stirred to obtain a UV-curable resin composition. The preparation was carried out in a room using a yellow lamp to suppress the reaction of the initiator due to visible light.

[0088] (Preparation of Polymer Electrolyte Membrane) Using a die coater, an ultraviolet-curable resin composition was applied to the release-treated surface of a 75 μm-thick first release PET film (PET75X manufactured by Lintec Corporation) so that the thickness after curing would be 150 μm. Next, a second release PET film (PET75X manufactured by Lintec Corporation) was placed on the resin surface so that the applied resin surface and the release-treated surface were in contact. Thereafter, ultraviolet light was irradiated using a high-pressure mercury lamp (Industrial UV Checker, UVR-T1 manufactured by Topcon Technohouse Corporation) to cure the ultraviolet-curable resin composition. The irradiation conditions were an illuminance of 150±20 W / cm ２ , cumulative light intensity 2000 mJ / cm ２ The resin layer, i.e., the polymer electrolyte membrane, was obtained by peeling off the first and second release PET films from a laminate in which the first release PET film, the resin layer, and the second release PET film were laminated in this order.

[0089] (Evaluation of proton conductivity) The proton conductivity of the obtained polymer electrolyte membrane was evaluated. First, the resistance value, membrane thickness, and electrode area of ​​the polymer electrolyte membrane were measured. The obtained values ​​were applied to formula (1) to calculate the proton conductivity. Next, the proton conductivity was evaluated according to the following criteria.

[0090] Equation (1) Proton conductivity (mS / cm) = 1000 × polymer electrolyte membrane thickness (cm) / (electrode area (cm) ２ ) × resistance value (Ω), and the S in the unit of proton conductivity (mS / cm) represents siemens.

[0091] Excellent: 8 mS / cm or more; Good: 3 mS / cm or more but less than 8 mS / cm; Poor: less than 3 mS / cm.

[0092] To determine the "resistance value" in formula (1), the AC impedance of the polymer electrolyte membrane was measured using an electrochemical measurement device (Hz-Pro S4, manufactured by Hokuto Denko Corporation) and a high-precision electrical resistance measurement device (IMC-008D(A), manufactured by Imoto Machinery Works, Ltd.).

[0093] Specifically, a 4 cm square polymer electrolyte membrane was cut and immersed in ion-exchanged water at 25°C for 24 hours, then removed from the ion-exchanged water. The polymer electrolyte membrane was then wiped clean to prepare a measurement sample. The measurement sample was then sandwiched between a pair of gold-plated electrodes equipped in a high-precision electrical resistance measurement device at a pressure of 1 MPa. The working electrode of the electrochemical measurement device was then connected to one of the gold-plated electrodes, and the reference electrode of the electrochemical measurement device was connected to the other gold-plated electrode. The counter electrode of the electrochemical measurement device was also connected to the reference electrode, and the AC impedance of the polymer electrolyte membrane was measured. The measurement conditions were 25°C, 50% RH relative humidity, a measurement frequency of 1 kHz to 1 MHz, and an AC amplitude of 10 mV.

[0094] A Nyquist plot was created from the measured AC impedance using dedicated software (Hokuto Denko Corporation, EIS 1.2.2) to determine the resistance value of the polymer electrolyte membrane. Note that a "Nyquist plot" refers to a plot of the AC impedance of the object measured at different frequencies on a complex plane with the X axis representing the real component and the Y axis representing the imaginary component.

[0095] The proton conductivity of the polymer electrolyte membrane made of the ultraviolet curable resin composition of Example 1, determined by the above-mentioned method, was 7.5 mS / cm, and was evaluated as Good.

[0096] Next, the strength of the polymer electrolyte membrane was evaluated by measuring the gas leakage amount and tensile strength of the polymer electrolyte membrane.

[0097] (Gas Leakage Amount) The gas leakage amount of the polymer electrolyte membrane was measured by measuring the amount of air leakage. Specifically, the air leakage amount was measured using an air leak tester (LS-R910, manufactured by Cosmo Instruments Co., Ltd.). First, a polymer electrolyte membrane cut into a 90 mm square was immersed in ion-exchanged water at 25°C for 24 hours. Next, the polymer electrolyte membrane was removed from the ion-exchanged water, and water droplets on the surface were wiped off. The polymer electrolyte membrane was then placed in the chamber of the air leak tester so as not to create any gaps. Next, air was flowed into the chamber at a pressure of 50 kPa for 30 seconds, and the amount of air leaking out was taken as the gas leakage amount.

[0098] Based on the results of the gas leakage amount, the evaluation was made as follows: Good: The polymer electrolyte membrane was not broken and the gas leakage amount was less than 100 ml; Poor: The polymer electrolyte membrane was broken, or the polymer electrolyte membrane was not broken but the gas leakage amount was 100 ml or more.

[0099] The amount of gas leakage from the polymer electrolyte membrane of Example 1 measured by the above-mentioned method was 1.0 ml or less, and the polymer electrolyte membrane was not broken, so the evaluation was Good.

[0100] (Tensile Strength) The tensile strength of the polymer electrolyte membrane was measured in accordance with JIS K 7161-2 using a tensile tester (Shimadzu Corporation, EZ-TEST EZ-SX 100N). Specifically, the polymer electrolyte membrane was cut into a dumbbell shape (No. 2 test piece specified in JIS K 7161-2) and immersed in ion-exchanged water at 25°C for 24 hours. Thereafter, the polymer electrolyte membrane was removed from the ion-exchanged water, and water droplets on the surface were wiped off to prepare a sample. This sample was placed in the tensile tester and measured at a test speed of 50 mm / min.

[0101] The obtained tensile strength was evaluated as follows: Excellent: 4 MPa or more, Good: 1 MPa or more and less than 3 MPa, Poor: less than 1 MPa.

[0102] The tensile strength of the polymer electrolyte membrane of Example 1 measured by the above-mentioned method was 1.2 MPa or less, and the evaluation was Good.

[0103] As described above, it was found that the polymer electrolyte membrane of Example 1 had a proton conductivity of 7.5 mS / cm, a small amount of gas leakage, and a strength of 1 MPa or more. These results demonstrate that the polymer electrolyte membrane of Example 1 has excellent proton conductivity and high strength. The polymer electrolyte membrane of Example 1 can be suitably used as a polymer electrolyte membrane for solid polymer fuel cells and solid polymer water electrolysis devices.

[0104] (Example 2) to (Example 11) and (Comparative Example 1) to (Comparative Example 7) The type and content of each component contained in the ultraviolet-curable resin composition of each Example and Comparative Example are shown in Table 1 and Table 2. For the ultraviolet-curable resin compositions of Examples 2 to 11 and Comparative Examples 1 to 7, the ultraviolet-curable resin compositions were prepared in the same manner as in Example 1, except that the type and content of each component were changed, and polymer electrolyte membranes were produced from them.

[0105]

[0106]

[0107] The results of the proton conductivity, gas leakage amount, and tensile strength of the polymer electrolyte membranes of each Example and Comparative Example are shown in Tables 3 and 4. The proton conductivity, gas leakage amount, and tensile strength of the polymer electrolyte membranes of Examples 2 to 11 and Comparative Examples 1 to 7 were measured using the same methods as those used to measure the proton conductivity and gas leakage amount of the polymer electrolyte membrane of Example 1. The unit of content in the tables is "parts by weight" unless otherwise specified.

[0108]

[0109]

[0110] As shown in Table 3, the polymer electrolyte membranes of Examples 2 to 11 were also found to have excellent proton conductivity and high strength. Furthermore, the polymer electrolyte membranes of Examples 2 to 11 can also be suitably used as polymer electrolyte membranes for solid polymer fuel cells and solid polymer water electrolysis devices.

[0111] The polymer electrolyte membranes of Comparative Examples 1 to 5 shown in Table 4 were evaluated as poor in at least one of the proton conductivity, gas leakage amount, and tensile strength. The polymer electrolyte membrane of Comparative Example 6 could not be formed. The polymer electrolyte membrane of Comparative Example 7 could be formed. However, the membrane dissolved when immersed in ion-exchanged water, and therefore the proton conductivity, gas leakage amount, and tensile strength could not be measured.

[0112] From the above results, it was found that the polymer electrolyte membrane formed from the ultraviolet-curable resin composition of this embodiment has excellent proton conductivity and high strength.

[0113] Furthermore, the polymer electrolyte membranes of Examples 1 to 11 were evaluated for chemical resistance, water resistance, initial viscosity, and pot life. Hereinafter, the ultraviolet-curable resin composition of Example 3 and the polymer electrolyte membrane composed of the ultraviolet-curable resin composition of Example 3 will be described as examples.

[0114] (Chemical Resistance) The chemical resistance was evaluated as follows. First, 30 wt % hydrogen peroxide solution (manufactured by Wako Pure Chemical Industries, Ltd.) was placed in a plastic container, and the Fe ２＋Iron sulfate heptahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) was added until the ion concentration reached 95 ppm to obtain a chemical solution. 100 ml of the chemical solution was added to another plastic container, and a polymer electrolyte membrane cut into a 4 cm square was immersed therein and left at room temperature (23°C ± 5°C) for one week. The membrane was then removed from the chemical solution, and the state of the polymer electrolyte membrane was visually confirmed.

[0115] The chemical resistance was evaluated according to the following criteria: Excellent: No change in the appearance of the polymer electrolyte membrane; Good: Part of the polymer electrolyte membrane was dissolved, but it could still be used as a polymer electrolyte membrane for a polymer electrolyte fuel cell; Poor: The polymer electrolyte membrane was completely dissolved.

[0116] Although the polymer electrolyte membrane of Example 3 was partially dissolved, it could be used as a polymer electrolyte membrane for a polymer electrolyte fuel cell and was evaluated as Good.

[0117] (Water Resistance) A polymer electrolyte membrane cut into a 4 cm square was immersed in ion-exchanged water at 25° C. for 24 hours, and then the polymer electrolyte membrane was taken out and the surface of the membrane was visually inspected. The water resistance was evaluated according to the following criteria: Good: No cracks were observed, Poor: Cracks were observed.

[0118] The polymer electrolyte membrane of Example 3 was free of cracks and was evaluated as Good.

[0119] (Initial Viscosity) The ultraviolet-curable resin composition of Example 3 was prepared at 25°C. The viscosity of the ultraviolet-curable resin composition immediately after preparation was measured using an E-type viscometer (TV200, manufactured by Toki Sangyo Co., Ltd.). The obtained viscosity was evaluated according to the following criteria. This viscosity is referred to as the initial viscosity. Good: Viscosity is 10 Pa·s or less, Poor: Viscosity is greater than 10 Pa·s.

[0120] The initial viscosity of the ultraviolet-curable resin composition of Example 3 was 10 Pa s or less, and the evaluation was Good. It was found that an ultraviolet-curable resin composition having an initial viscosity of 10 Pa s or less can be applied to a film surface without unevenness.

[0121] (Pot Life) The pot life test is a test to evaluate the period during which a polymer electrolyte membrane can be produced from an ultraviolet-curable resin composition. Specifically, the ultraviolet-curable resin composition is placed in a sealed container. The sealed container is stored at 25°C for 3 days under light-shielded conditions. The viscosity of the ultraviolet-curable resin composition after storage was then measured at 25°C. The obtained viscosity was evaluated according to the following criteria. An E-type viscometer (TV200, manufactured by Toki Sangyo Co., Ltd.) was used. Good: Viscosity is 10 Pa·s or less. Poor: Viscosity is greater than 10 Pa·s.

[0122] The viscosity of the ultraviolet-curable resin composition of Example 3 was 10 Pa s or less, and the evaluation was Good. It was found that an ultraviolet-curable resin composition having a viscosity of 10 Pa s or less after the pot life test can be applied to the film surface without uneven coating.

[0123] Examples 1 to 11 Table 5 shows the chemical resistance and water resistance of the polymer electrolyte membrane of each example, the initial viscosity of the ultraviolet-curable resin composition of each example, and the pot life.

[0124]

[0125] As shown in Table 5, the UV-curable resin compositions of Examples 3 to 11, which used adduct-based urethane (meth)acrylate and carbonate-based urethane (meth)acrylate, had good initial viscosity and pot life, and were found to have excellent processability as resin compositions for producing polymer electrolyte membranes. Furthermore, polymer electrolyte membranes formed from such UV-curable resin compositions were found to have excellent chemical resistance and water resistance. Solid polymer fuel cells and solid polymer water electrolysis devices equipped with such polymer electrolyte membranes use polymer electrolyte membranes that are resistant to deterioration, and therefore have long service lives as fuel cells and water electrolysis devices.

[0126] The present invention allows various embodiments and modifications without departing from the broad spirit and scope of the present invention. Furthermore, the above-described embodiments are intended to illustrate the present invention and do not limit the scope of the present invention. That is, the scope of the present invention is defined by the claims, not the embodiments. Various modifications made within the scope of the claims and within the scope of the meaning of the invention equivalent thereto are considered to be within the scope of the present invention.

[0127] This application is based on Japanese Patent Application No. 2023-214210, filed on December 19, 2023. The specification, claims, and drawings of Japanese Patent Application No. 2023-214210 are incorporated herein by reference.

[0128] (Appendix) Various aspects of the present disclosure are collectively described below as appendices. (Appendix 1) A polymerizable composition comprising: a urethane (meth)acrylate having a weight average molecular weight of 1,500 to 20,000 and a double bond equivalent of 600 to 7,500 g / mol, a (meth)acrylate monomer having a molecular weight of 150 to 300, a vinyl monomer having an acidic functional group, and a photopolymerization initiator, wherein the content of the urethane (meth)acrylate is 20 to 45% by weight, based on a total of 100% by weight of the urethane (meth)acrylate, the (meth)acrylate monomer, and the vinyl monomer, and the content of the (meth)acrylate monomer is 15 to 45% by weight, based on a total of 100% by weight of the urethane (meth)acrylate, the (meth)acrylate monomer, and the vinyl monomer. the content of the vinyl monomer is 20% by weight or more and 55% by weight or less, relative to 100% by weight of the total of the urethane (meth)acrylate, the (meth)acrylate monomer, and the vinyl monomer;

[0129] (Appendix 2) The ultraviolet-curable resin composition according to Appendix 1, wherein the acidic functional group is at least one selected from the group consisting of a carboxyl group, a phosphonic acid group, a sulfonic acid group, and a phosphoric acid group.

[0130] (Appendix 3) The ultraviolet-curable resin composition according to Appendix 1 or Appendix 2, wherein the number of the acidic functional groups in the vinyl monomer is 1 or 2.

[0131] (Appendix 4) A polymer electrolyte membrane comprising the cured ultraviolet-curable resin composition according to any one of Appendices 1 to 3.

[0132] (Supplementary Note 5) A polymer electrolyte fuel cell comprising: the polymer electrolyte membrane according to Supplementary Note 4; an anode catalyst layer formed on one side of the polymer electrolyte membrane; a cathode catalyst layer formed on the other side of the polymer electrolyte membrane; a first gas diffusion layer formed on the other side of the anode catalyst layer opposite to the one side on which the polymer electrolyte membrane is formed; a second gas diffusion layer formed on the other side of the cathode catalyst layer opposite to the one side on which the polymer electrolyte membrane is formed; a first separator disposed on the other side of the first gas diffusion layer opposite to the one side on which the anode catalyst layer is formed; and a second separator disposed on the other side of the second gas diffusion layer opposite to the one side on which the cathode catalyst layer is formed.

[0133] (Supplementary Note 6) A solid polymer water electrolysis device comprising: the polymer electrolyte membrane according to Supplementary Note 4; an anode catalyst layer formed on one side of the polymer electrolyte membrane; a cathode catalyst layer formed on the other side of the polymer electrolyte membrane; a first gas diffusion layer formed on the other side of the anode catalyst layer opposite to the one side on which the polymer electrolyte membrane is formed; a second gas diffusion layer formed on the other side of the cathode catalyst layer opposite to the one side on which the polymer electrolyte membrane is formed; a first separator disposed on the other side of the first gas diffusion layer opposite to the one side on which the anode catalyst layer is formed; and a second separator disposed on the other side of the second gas diffusion layer opposite to the one side on which the cathode catalyst layer is formed.

[0134] (Appendix 7) A method for producing a polymer electrolyte membrane, comprising: a preparation step of preparing the ultraviolet-curable resin composition according to any one of Appendices 1 to 3; a resin layer formation step of forming a resin layer composed of the ultraviolet-curable resin composition on one separate film; a film arrangement step of arranging another separate film on one surface of the resin layer that is opposite to the surface on which the one separate film is arranged; a curing step of irradiating the resin layer with ultraviolet light through the one separate film or the other separate film to cure the resin layer; and a peeling step of peeling the one separate film and the other separate film from the cured resin layer.

[0135] 10 Proton exchange type solid polymer fuel cell, 100 Proton exchange type solid polymer water electrolysis device, 20, 120 Anode electrode, 30, 130 Cathode electrode, 40 Polymer electrolyte membrane, 41, 141 Anode catalyst layer, 42, 142 Cathode catalyst layer, 43, 44, 143, 144 Gas diffusion layer, 51, 52, 151, 152 Separator, 53, 54, 153, 154 Groove, 61, 162 Oxygen, 62, 163 Water, 63, 161 Hydrogen, 65, 67, 165 Supply channel, 66, 68, 166, 168 Discharge channel, 70 External circuit, 71, 171 Electrons, 72, 172 Protons, 170 Power source.

Claims

1. A composition comprising: a urethane (meth)acrylate having a weight average molecular weight of 1,500 or more and 20,000 or less and a double bond equivalent of 600 g / mol or more and 7,500 g / mol or less; a (meth)acrylate monomer having a molecular weight of 150 or more and 300 or less; a vinyl monomer having an acidic functional group; and a photopolymerization initiator, wherein the content of the urethane (meth)acrylate is 20% by weight or more and 45% by weight or less with respect to a total of 100% by weight of the urethane (meth)acrylate, the (meth)acrylate monomer, and the vinyl monomer, and the content of the (meth)acrylate monomer is 15% by weight or more and 45% by weight or less with respect to a total of 100% by weight of the urethane (meth)acrylate, the (meth)acrylate monomer, and the vinyl monomer, the content of the vinyl monomer is 20% by weight or more and 55% by weight or less, based on 100% by weight of the total of the urethane (meth)acrylate, the (meth)acrylate monomer, and the vinyl monomer.

2. The ultraviolet-curable resin composition according to claim 1, wherein the acidic functional group is at least one selected from the group consisting of a carboxyl group, a phosphonic acid group, a sulfonic acid group, and a phosphoric acid group.

3. The ultraviolet-curable resin composition according to claim 1 or 2, wherein the number of the acidic functional groups of the vinyl monomer is 1 or 2.

4. A polymer electrolyte membrane comprising the cured ultraviolet-curable resin composition according to any one of claims 1 to 3.

5. A solid polymer electrolyte fuel cell comprising: the polymer electrolyte membrane according to claim 4; an anode catalyst layer formed on one side of the polymer electrolyte membrane; a cathode catalyst layer formed on the other side of the polymer electrolyte membrane; a first gas diffusion layer formed on the other side of the anode catalyst layer opposite to the one side on which the polymer electrolyte membrane is formed; a second gas diffusion layer formed on the other side of the cathode catalyst layer opposite to the one side on which the polymer electrolyte membrane is formed; a first separator disposed on the other side of the first gas diffusion layer opposite to the one side on which the anode catalyst layer is formed; and a second separator disposed on the other side of the second gas diffusion layer opposite to the one side on which the cathode catalyst layer is formed.

6. A solid polymer water electrolysis device comprising: the polymer electrolyte membrane according to claim 4; an anode catalyst layer formed on one side of the polymer electrolyte membrane; a cathode catalyst layer formed on the other side of the polymer electrolyte membrane; a first gas diffusion layer formed on the other side of the anode catalyst layer opposite to the one side on which the polymer electrolyte membrane is formed; a second gas diffusion layer formed on the other side of the cathode catalyst layer opposite to the one side on which the polymer electrolyte membrane is formed; a first separator disposed on the other side of the first gas diffusion layer opposite to the one side on which the anode catalyst layer is formed; and a second separator disposed on the other side of the second gas diffusion layer opposite to the one side on which the cathode catalyst layer is formed.

7. A method for producing a polymer electrolyte membrane, comprising: a preparation step of preparing an ultraviolet-curable resin composition according to any one of claims 1 to 3; a resin layer formation step of forming a resin layer composed of the ultraviolet-curable resin composition on one separate film; a film arrangement step of arranging another separate film on one side of the resin layer that is the opposite side to the side on which the one separate film is arranged; a curing step of irradiating the resin layer with ultraviolet light through the one separate film or the other separate film to harden the resin layer; and a peeling step of peeling off the one separate film and the other separate film from the hardened resin layer.

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