JP4636235B2 - Liquid curable resin composition for electrolyte membrane / electrode bonding and method for producing electrolyte membrane / electrode assembly - Google Patents

Description

  The present invention relates to a liquid curable resin composition for joining an electrolyte membrane / electrode of a polymer electrolyte fuel cell and a method for producing an electrolyte membrane / electrode assembly.

  A fuel cell using an electrolyte membrane for a polymer electrolyte fuel cell has a low operating temperature of 100 ° C. or lower, and its energy density is high. Therefore, it is expected to be widely put into practical use as a power source for electric vehicles and a simple auxiliary power source. . In this polymer electrolyte fuel cell, there are important elemental technologies related to electrolyte membranes, platinum-based catalysts, gas diffusion electrodes, and electrolyte membrane-electrode assemblies. Among these, electrolyte membrane-electrode assemblies include It is one of the most important technologies involved in fuel cell characteristics.

Conventionally, the following two methods are generally known as a method for producing an electrolyte membrane / electrode assembly of a polymer electrolyte fuel cell.
(1) A method of directly depositing an electrode catalyst on an electrolyte membrane (for example, see Patent Document 1: Japanese Patent Publication No. 58-47471).
(2) A method of producing an electrode sheet having catalytic ability and bonding it to an electrolyte membrane by hot pressing (hereinafter referred to as hot pressing method. For example, Patent Documents 2 to 4: US Pat. No. 3,134,697, US Pat. No. 3,297,484) No. specification and Japanese Patent Publication No. 2-7398).

  At present, the hot pressing method (2), which can effectively use a small amount of catalyst, has become the mainstream. In the research on solid polymer fuel cells so far, as a method for forming a catalyst layer on a gas diffusion electrode sheet, for example, an electrochemical deposition method (see Patent Document 5: US Pat. No. 5,084,144), a catalyst, and the like. Various methods such as paste application (see Patent Document 6: Japanese Patent Laid-Open No. Hei 4-162365) have been proposed, but the method of finally joining the ion exchange membrane has relied on hot pressing.

In the hot press method, in order to obtain the bonding strength between the electrolyte membrane and the electrode and the electrical bonding state, the temperature is 100 ° C. or more, which is the glass transition point of the resin forming the electrolyte membrane, and the pressure seems to partially penetrate the electrode. In general, the amount of 20 kgf / cm ² or more necessary for achieving the above is generally used.

However, when hot-pressing at 100 ° C. or higher and 20 kgf / cm ² or higher, an electrode made of carbon paper or carbon cloth or a fluorine-based resin such as polytetrafluoroethylene forming a pore structure is easily deformed, There was a problem that the fuel diffusibility deteriorated due to the decrease in the rate and the collapse of the pores.

  Moreover, when the electrolyte membrane and the electrode are pressed at a high temperature, the moisture content decreases due to drying of the electrolyte membrane, the membrane resistance increases, and if the hot press temperature is too high, the membrane may be altered. There are problems that occur, and when the hot press pressure is too high, the film is broken.

  In the hot press method, these problems are unavoidable, and a process for joining the electrode and the ion exchange membrane at room temperature and under no pressure has been demanded. Moreover, when producing a large-area joined body, non-heating and non-pressurization are more advantageous in terms of mass productivity.

In order to improve productivity and adhesiveness, Patent Document 7: Japanese Patent Laid-Open No. 7-220741 proposes that an electrolyte membrane dissolved in a specific solvent is used as a bonding agent to bond at a relatively low temperature. However, the polymer electrolyte membrane tends to stay on the surface of the base material and does not easily penetrate into the inside, so that the bonding property is not always sufficient.
Japanese Patent Publication No.58-47471 US Pat. No. 3,134,697 US Pat. No. 3,297,484 Japanese Patent Publication No.2-7398 US Pat. No. 5,084,144 JP-A-4-162365 Japanese Patent Laid-Open No. 7-220741

  The present invention has been made in view of the above circumstances. In an electrolyte membrane / electrode assembly for a polymer electrolyte fuel cell, the present invention solves the above problems and makes it possible to easily produce a high-performance assembly. An object of the present invention is to provide a liquid curable resin composition for joining an electrolyte membrane / electrode and a method for producing an electrolyte membrane / electrode assembly using the same.

As a result of intensive studies to achieve the above object, the present inventors have
(A) as a monomer having a one ethylenically unsaturated group and one sulfonic acid group or its precursor group in the molecule, styrene sulfonic acid, allyl sulfonic acid, allyl oxybenzene sulfonic acid, acrylamide 2 A sulfonic acid group-containing monomer selected from methylpropanesulfonic acid, vinylsulfonic acid, fluorovinylsulfonic acid, perfluoroalkylsulfonic acid fluorovinyl ether and perfluorovinyl ether sulfonic acid, or an alkali metal salt thereof ,
(B) an ethylenically unsaturated group copolymerizable or addition reaction to groups as oligomers having in one molecule at least two, polyether acrylated DOO
A liquid curable resin composition for joining an electrolyte membrane and an electrode having a viscosity at 25 ° C. of 100,000 mPa · s or less, at a monomer / oligomer mass ratio of 10/90 to 90/10. The liquid curable resin composition is applied so that the liquid curable resin composition is interposed between the electrolyte membrane and the electrode, and then cured by heating and / or radiation irradiation, thereby the electrolyte membrane and the electrode. However, it was found that the cured film can be satisfactorily bonded without hot pressing, and that an electrolyte membrane / electrode assembly useful for a fuel cell can be advantageously produced industrially, and the present invention has been made.

Therefore, the present invention provides the following liquid curable resin composition for electrolyte membrane / electrode bonding and a method for producing an electrolyte membrane / electrode assembly.
[Claim 1]
(A) as a monomer having a one ethylenically unsaturated group and one sulfonic acid group or its precursor group in the molecule, styrene sulfonic acid, allyl sulfonic acid, allyl oxybenzene sulfonic acid, acrylamide 2 A sulfonic acid group-containing monomer selected from methylpropanesulfonic acid, vinylsulfonic acid, fluorovinylsulfonic acid, perfluoroalkylsulfonic acid fluorovinyl ether and perfluorovinyl ether sulfonic acid, or an alkali metal salt thereof ,
(B) an ethylenically unsaturated group copolymerizable or addition reaction to groups as oligomers having in one molecule at least two, polyether acrylated DOO
A liquid curable resin composition for joining an electrolyte membrane and an electrode, characterized by having a monomer / oligomer mass ratio of 10/90 to 90/10 and a viscosity at 25 ° C. of 100,000 mPa · s or less .
[Claim 2]
The liquid curable resin composition for bonding an electrolyte membrane / electrode according to claim 1 is applied to at least one of an electrolyte membrane or an electrode prepared in advance, and the liquid curable resin composition is interposed between the electrolyte membrane and the electrode. After being bonded together, the liquid curable resin composition is cured by heating and / or radiation irradiation to join the electrolyte membrane and the electrode cured membrane, and the electrolyte for a polymer electrolyte fuel cell, Manufacturing method of membrane / electrode assembly.

  According to the present invention, since the electrolyte membrane and the electrode can be joined with sufficient strength without hot pressing, the process of manufacturing the joined body of the electrolyte membrane and the electrode is simplified. In addition, since there is no deterioration of the electrolyte membrane or electrode due to heat, it is possible to produce a fuel cell with low internal resistance, which is particularly useful as an electrolyte membrane / electrode assembly for solid polymer fuel cells and direct methanol fuel cells. is there.

The liquid curable resin composition for electrolyte membrane / electrode bonding of the present invention comprises a monomer having at least one ethylenically unsaturated group and at least one ion-conducting group or a precursor group thereof in one molecule. , those containing the oligomer of at least two chromatic ethylenically unsaturated group copolymerizable or addition reaction to groups in a molecule.

Compounds having at least one ion-conducting group or a precursor group of at least one ethylenically unsaturated group and scan sulfonic acid group in one molecule used in the present invention (-SO ₃ H) is the scan styrene sulfonic acid, allyl sulfonic acid, allyl oxybenzene sulfonic acid, acrylamido 2-methylpropane sulfonic acid, vinyl sulfonic acid, fluoro vinyl sulfonic acid, perfluoroalkylsulfonic acid fluorovinyl ether, a sulfonic acid group selected from the perfluorovinyl ether sulfonate Containing monomer, its alkali metal salt .

  Among these, monomers having a molecular weight of less than 1,000, particularly 200 to 500, are desirable for increasing the ion (proton) conductivity of the cured film.

  In the present invention, those having a sulfonic acid group and further a sulfonic acid group precursor group as the ion conductive group are preferred from the viewpoint of high ionic conductivity. Examples of the precursor group of the sulfonic acid group include a metal salt of sulfonic acid, a glycidyl group for forming a sulfonic acid metal salt with sodium sulfite and the like.

In oligomer having at least two reactive groups per molecule for use in the present invention, the reactive group, Ri Oh ethylenically unsaturated group copolymerizable or addition reactions group, a vinyl group, an allyl group, ( Examples of such oligomers include polyethylene glycol di (meth) acrylate, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polybutylene glycol diurethane (meth) acryloyl group, mercapto group, and hydrogen atom directly bonded to a silicon atom. Examples include polyether polyacrylates such as (meth) acrylates, polyester polyacrylates, (meth) acryloxy group-containing organopolysiloxanes, vinyl group-containing organopolysiloxanes, and hydrogen atom-containing organopolysiloxanes directly connected to silicon atoms. It is a number average molecular weight of 1,000 or more, and particularly those of 1,000 to 4,000, coatability of the composition, desirable for excellent curability.

In the liquid curable resin composition for bonding an electrolyte membrane / electrode of the present invention, a compound (monomer) having at least one ethylenically unsaturated group and at least one ion-conducting group or precursor group in one molecule. ) And an oligomer having at least two reactive groups in one molecule (monomer / oligomer) is 10/90 to 90/10, preferably 20/80 to 80/20, more preferably 30/70. 70 / Ru 30 der. If the mass ratio of the monomer to the oligomer is less than 10/90, the ionic conductivity may decrease, and if it exceeds 90/10, the curability may be impaired.

  The liquid curable resin composition for joining an electrolyte membrane / electrode of the present invention includes a monomer having no ion conductive group or its precursor group, for example, styrene, t, for the purpose of adjusting the joining property between the electrolyte membrane and the electrode. -Ion conductivity of electrolyte membrane / electrode assembly obtained by using -butylstyrene, n-lauryl acrylate, 2-ethylhexyl acrylate, n-hexyl acrylate, isooctyl acrylate, 2-phenoxyethyl acrylate, 2-ethoxyethyl acrylate, etc. You may use together in the range which does not impair.

  Furthermore, in the present invention, heteropolyacids such as phosphotungstic acid for the purpose of improving ion conductivity, or inorganic compounds such as oxides, nitrides and carbides for the purpose of preventing the permeation of hydrogen or alcohol, water, and oxygen in fuel cells. It can be added as a filler. Specific examples of the filler include boron nitride, silicon carbide, and silica.

  The method for producing the liquid curable resin composition for bonding an electrolyte membrane / electrode of the present invention is not particularly limited, and is prepared according to a conventional method. In addition, the viscosity at 25 ° C. measured by a rotational viscometer of the liquid curable resin composition for electrolyte membrane / electrode bonding is 100,000 mPa · s or less from the viewpoint of applicability, and a desirable viscosity is 100 to 10,000 mPa · s. s. When the viscosity of the composition exceeds 100,000 mPa · s, the leveling property is poor, and it becomes difficult to apply thinly and uniformly. When the viscosity is less than 100 mPa · s, the penetration into the repellent or the substrate may be increased. .

  In the liquid curable resin composition for joining an electrolyte membrane and an electrode in the present invention, a solvent can be used in combination for the purpose of adjusting the viscosity. The solvent used at this time is preferably a solvent that uniformly dissolves the composition, for example, ketones such as acetone and methyl ethyl ketone, esters such as ethyl acetate and butyl acetate, ethers such as tetrahydrofuran and dioxane, benzene, toluene and the like. Aromatic hydrocarbons, aliphatic or alicyclic hydrocarbons such as n-heptane, n-hexane, cyclohexane, polar solvents such as N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, water, or These mixed solvents are used. Among these, polar solvents are more preferable.

  Apply the above liquid curable resin composition for electrolyte membrane / electrode bonding onto an electrode such as carbon paper carrying a metal catalyst such as platinum, and paste the electrolyte membrane on it, and then liquid curing for electrolyte membrane / electrode bonding. The other electrode coated with the conductive resin composition is bonded to the opposite surface of the electrolyte membrane and cured by heating and / or irradiation to produce an electrolyte membrane / electrode assembly. Instead, the resin composition may be applied to the electrolyte membrane, and the electrode may be bonded thereto.

  In order to cure the liquid curable resin composition for bonding an electrolyte membrane / electrode of the present invention, it is necessary to apply heat and / or radiation. In the present invention, after the composition is heated, it can be further cured by irradiation with radiation. The atmosphere for curing the composition is preferably an inert gas atmosphere such as nitrogen, helium or argon in order to facilitate radical polymerization. The oxygen concentration in the gas is preferably 500 ppm or less, and more preferably 200 ppm or less.

  Here, in the case of curing by heating, the temperature is preferably a temperature at which the electrolyte membrane and the electrode do not change, 120 ° C. or less, desirably 80 to 100 ° C., the heating time is 0.1 to 30 minutes, desirably 3 to 10 minutes. When the temperature of the composition is less than 80 ° C., curing may be insufficient. When the temperature exceeds 120 ° C., the electrolyte membrane, the electrode, and the liquid curable resin for electrolyte membrane / electrode bonding may be altered. If the heating time is less than 0.1 minutes, the curability of the composition may be insufficient, and if it exceeds 30 minutes, the productivity may deteriorate. In addition, when performing heat curing, in order to accelerate | stimulate hardening of a composition, a well-known polymerization initiator can be used, For example, a benzoyl peroxide, an azobisisobutyronitrile, etc. are illustrated.

  Examples of radiation include electron beams, γ-rays, X-rays, and ultraviolet rays, and electron beams are particularly preferable. The temperature when irradiating with radiation may be around room temperature, but in order to adjust the viscosity of the resin composition so that it is easy to apply, or to keep the film thickness and the state of the coating surface constant, the temperature and irradiation of the resin composition are previously determined. It is better to adjust the temperature of the atmosphere to be constant. In this case, the temperature of the resin composition and the irradiation atmosphere is preferably in the range of 25 to 60 ° C. and constant.

  When curing using an electron beam, an accelerator having an acceleration voltage of 50 to 300 kV can be used, a desirable absorbed dose is 5 kGy or more, a more desirable absorbed dose is 5 to 500 kGy, and a more desirable absorbed dose is 10 to 100 kGy. If it is less than 5 kGy, curing may be insufficient, and if it exceeds 500 kGy, the resin may be decomposed.

Moreover, when making it harden | cure by irradiating an ultraviolet-ray, desirable irradiation energy is 20 mJ / cm < ² > or more, and more desirable irradiation energy is 50-1,000 mJ / cm < ² >. Irradiation energy may become insufficient curing is less than 20 mJ / cm ^2, a resin besides Enenrugi is wasted exceeds 1,000 mJ / cm ² there is a risk of damage. In addition, when performing ultraviolet curing, in order to accelerate | stimulate hardening of a composition, a well-known photoinitiator can be used. Known photopolymerization initiators include, for example, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-2-phenylacetophenone, phenylacetophenone diethyl ketal, alkoxyacetophenone, benzylmethyl ketal, benzophenone and 3,3-dimethyl-4. Benzophenone derivatives such as methoxybenzophenone, 4,4-dimethoxybenzophenone, 4,4-diaminobenzophenone, benzoylalkyl benzoate, bis (4-dialkylaminophenyl) ketone, benzyl derivatives such as benzyl and benzylmethyl ketal, benzoyl and benzoin Benzoin derivatives such as butyl methyl ketal, benzoin isopropyl ether, 2-hydroxy-2-methylpropiophenone, 2,4-diethylthioxan And thioxanthone derivatives such as 2,4-dichlorothioxanthone, fluorene, 2-methyl-1- [4- (methylthio) phenyl] 2-morpholinopropane-1,2-benzyl-2-dimethylamino-1- (morpholinophenyl) ) -Butanone-1,2,4,6-trimethylbenzoyldiphenylphosphine oxide, phosphine oxide derivatives such as bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, benzoyl peroxide, t- Organic peroxides such as butyl peroxide and cumene hydroperoxide, organic azo such as azobiscyanovaleric acid, azobisbutyronitrile, azobis- (2,4-dimethyl) valeronitrile, azobis- (2-aminopropane) hydrochloride Compounds, etc. .

  These photopolymerization initiators may be used alone or in combination of two or more. A compounding quantity improves the sclerosis | hardenability of the composition of this invention, can be used in the range which does not impair a characteristic, and is normally used in 20 mass% or less in a composition. A preferred amount of use is 0.1 to 10% by mass, particularly 1 to 5% by mass.

  The film thickness of the electrolyte membrane / electrode bonding liquid curable resin composition is 100 μm or less, preferably 0.1 to 10 μm. When the thickness exceeds 100 μm, the resistance of the cured film increases when the electrolyte membrane / electrode assembly is used. When the thickness is less than 0.1 μm, the bonding resistance between the electrolyte membrane and the electrode becomes insufficient, so that the contact resistance increases and the output decreases. There is a fear.

  In addition, when it hardens | cures using the composition containing the compound which has an ion conductive precursor group, for example, the sulfonic acid metal salt in hardened | cured material ion-exchanges with acids, such as hydrochloric acid and a sulfuric acid, and a glycidyl group is a sulfurous acid. By making an acid treatment after forming a sulfonic acid metal salt with sodium or the like, the ion conductive precursor group present in the cured product can be made an ion conductive group.

The liquid curable resin composition for joining an electrolyte membrane and an electrode according to the present invention plays a role of improving the joining property between an electrolyte membrane for a fuel cell and an electrode. It can be manufactured by a method.
(I) A liquid curable resin composition for electrolyte membrane / electrode bonding is applied on the first electrode on which the catalyst is supported, the electrolyte membrane is bonded together, and then heated and / or irradiated with radiation. The step of curing the object and bonding the electrolyte membrane and the electrode is performed.
(Ii) A liquid curable resin composition for electrolyte membrane / electrode bonding is applied on the first electrode carrying the catalyst, and the electrolyte membrane is bonded together. After the second electrode on which the catalyst coated with the resin composition is supported is bonded, heating and / or radiation is applied to cure the resin composition, and a step of joining the electrolyte membrane and the electrode is performed.

  FIG. 1 illustrates the method (ii). In FIG. 1, 1 is an air electrode in which a catalyst layer 3 is formed on a carbon paper 2, and 4 is a catalyst layer 6 that is also formed on a carbon paper 5. 7 is an electrolyte membrane, and 8 and 9 are layers of the liquid curable resin composition of the present invention. For example, the liquid curable resin composition layer 9 and the electrolyte are formed on the surface of the catalyst layer 6 of the fuel electrode 4. The film 7, the liquid curable resin composition layer 8, and the catalyst layer 3 surface of the air electrode 1 are laminated in this order, and then irradiated with radiation such as heating and / or electron beam to cure the compositions 8 and 9, An electrolyte membrane / electrode assembly is obtained.

  As an electrode on which the catalyst is supported, an electrode in which a catalyst is supported on an electrode (fuel electrode, air electrode) of a normal fuel cell can be used. In this case, the structure and material of these electrodes can be those known as fuel cells, and catalysts known as fuel cells, such as platinum-based catalysts, can also be used.

  Examples of the electrolyte membrane bonded to the electrode include a perfluorosulfonic acid electrolyte membrane having a perfluoroalkylene group as a main chain and a perfluoroethersulfonic acid in a side chain, polytetrafluoroethylene, ethylene / tetrafluoroethylene copolymer film, and the like. Examples include a radiation-grafted electrolyte membrane that is irradiated with radiation and grafted with styrene and divinylbenzene, and a hydrocarbon-based electrolyte membrane in which sulfonic acid groups are introduced into polybenzimidazole or polyetheretherketone. In addition, a film obtained by previously curing the composition of the present invention with heat and / or radiation can be used as an electrolyte membrane.

In the above process, in order to join the coating film or the electrolyte membrane to the electrode, it is only necessary to press the electrode at about 0.05 to 5 kgf / cm ² using a press or the like, without pressing the electrolyte membrane and the electrode at a high temperature. Even if it adheres well.

  The liquid curable resin composition for electrolyte membrane / electrode bonding and the electrolyte membrane / electrode assembly of the present invention are suitably used for fuel cells. A fuel cell has a thin solid polymer electrolyte membrane that is well adhered to each electrode between a fuel electrode and an air electrode, and a catalyst layer and a fuel diffusion layer on both sides of the solid polymer electrolyte membrane. In addition, a fuel cell having excellent power generation characteristics can be manufactured by arranging the separator.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example. In the following examples, the number average molecular weight indicates a polystyrene conversion value measured by gel permeation chromatography (GPC), and the viscosity is measured using a B-type rotational viscometer. 3. The value at 25 ° C. measured under the condition of the rotation speed of 30 rpm is shown.

[Example 1]
A reaction vessel was charged with 100 g of fluorotetraethylene glycol having a number average molecular weight of 410 and 0.05 g of 2,6-di-tert-butylhydroxytoluene (BHT), and 2,4-tolylene diisocyanate at 65 to 70 ° C. under nitrogen flow. 84.9 g was added dropwise. After the dropwise addition, the mixture was further reacted at 70 ° C. for 2 hours, then 0.02 g of dibutyltin dilaurate was added, and 56.6 g of 2-hydroxyethyl acrylate was added dropwise under dry air. Furthermore, it was made to react at 70 degreeC for 5 hours, and the fluoro polyether urethane acrylate oligomer (oligomer A) of the number average molecular weight 990 was obtained.

  50 g of oligomer A, 100 g of acrylamidomethylpropanesulfonic acid, 100 g of polyvinylidene fluoride powder (PVDF) having a number average molecular weight of 543,000, and 900 g of N, N-dimethylformamide (DMF) as a solvent are mixed, and the viscosity at 25 ° C. is 8, Fluorescent color transparent liquid curable resin composition B was obtained at 000 mPa · s.

  Next, using an applicator, the liquid curable resin composition B is applied to a glass plate to a thickness of 200 μm, and irradiated with an electron beam so that the acceleration voltage is 300 kV and the absorbed dose is 50 kGy in a nitrogen atmosphere with an oxygen concentration of 50 ppm or less. And cured to obtain an electrolyte membrane C having a thickness of about 30 μm.

Carbon paper TGP-H-060 (manufactured by Toray Industries, Inc.) is a catalyst paste made by kneading 5% isopropyl alcohol solution of Nafion (manufactured by Aldrich) and TEC10E50E (manufactured by Tanaka Kikinzoku) carrying 50% by mass of platinum. After coating using a wire bar so that a platinum catalyst might be set to 3 mg / cm < ² > above, it dried at 60 degreeC for 30 minute (s) in the hot air circulation type dryer, and the electrode (air electrode) was obtained.

Similarly, a platinum-ruthenium catalyst obtained by kneading carbon TEC61E54 (manufactured by Tanaka Kikinzoku Co., Ltd.) carrying 54% by mass of a platinum-ruthenium alloy into a paste is prepared on carbon paper TGP-H-060 (manufactured by Toray Industries, Inc.). Was applied using a wire bar so as to be 3 mg / cm ^2, and then dried in a hot air circulation dryer at 60 ° C. for 30 minutes to obtain an electrode (fuel electrode).

The liquid curable resin composition B is applied on the catalyst layer surface of these electrodes using an applicator so that the film thickness is about 20 μm, and is bonded to both surfaces of the electrolyte membrane C, and a roller of 5 kgf / cm ² at room temperature. Was reciprocated twice and crimped. Thereafter, using the electron beam irradiation apparatus, in the embodiment shown in FIG. 1, the liquid curable resin composition B was irradiated with an electron beam so that the acceleration voltage was 300 kV and the absorbed dose was 50 kGy in a nitrogen atmosphere with an oxygen concentration of 50 ppm or less. It cured well and the electrolyte membrane and each electrode were firmly bonded.

Using this electrolyte membrane / electrode assembly, methanol at a concentration of 1 M / L was used as fuel, and power was generated at 30 ° C., and an output of 20 mW / cm ² was obtained at a current of 100 mA / cm ² .

[Comparative Example 1]
The electrolyte membrane C was directly sandwiched between the fuel electrode (anode) and the air electrode (cathode) produced in Example 1 without applying the liquid curable resin composition, and a 5 kgf / cm ² roller was reciprocated ^twice at room temperature. Although it was crimped, it did not adhere at all.

It is sectional drawing explaining an example of the method of producing the electrolyte membrane electrode assembly of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air electrode 2,5 Carbon paper 3,6 Catalyst layer 4 Fuel electrode 7 Electrolyte membrane 8,9 Liquid curable resin composition

Claims (2)

(A) as a monomer having a one ethylenically unsaturated group and one sulfonic acid group or its precursor group in the molecule, styrene sulfonic acid, allyl sulfonic acid, allyl oxybenzene sulfonic acid, acrylamide 2 A sulfonic acid group-containing monomer selected from methylpropanesulfonic acid, vinylsulfonic acid, fluorovinylsulfonic acid, perfluoroalkylsulfonic acid fluorovinyl ether and perfluorovinyl ether sulfonic acid, or an alkali metal salt thereof ,
(B) an ethylenically unsaturated group copolymerizable or addition reaction to groups as oligomers having in one molecule at least two, polyether acrylated DOO
A liquid curable resin composition for joining an electrolyte membrane and an electrode, characterized by having a monomer / oligomer mass ratio of 10/90 to 90/10 and a viscosity at 25 ° C. of 100,000 mPa · s or less . The liquid curable resin composition for bonding an electrolyte membrane / electrode according to claim 1 is applied to at least one of an electrolyte membrane or an electrode prepared in advance, and the liquid curable resin composition is interposed between the electrolyte membrane and the electrode. After being bonded together, the liquid curable resin composition is cured by heating and / or radiation irradiation to join the electrolyte membrane and the electrode cured membrane, and the electrolyte for a polymer electrolyte fuel cell, Manufacturing method of membrane / electrode assembly.

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