JP5144024B2 - Electrode electrolyte for polymer fuel cell and use thereof - Google Patents

Description

  The present invention relates to an electrode electrolyte for a polymer electrolyte fuel cell, an electrode paste, an electrode, and a membrane-electrode assembly containing a polymer composed of a specific structural unit.

  Solid polymer fuel cells have high power density and can be operated at low temperatures, so they can be reduced in size and weight, and put into practical use as power sources for automobiles, stationary power sources, and portable devices. Is expected.

  A polymer electrolyte fuel cell is provided with a pair of electrodes on both sides of a proton conductive solid polymer electrolyte membrane, supplies pure hydrogen or reformed hydrogen as a fuel gas to one electrode (fuel electrode), oxygen gas or air Is supplied as an oxidant to the other electrode (air electrode) to generate electricity.

  The electrode of such a fuel cell is composed of an electrode electrolyte in which a catalyst component is dispersed (for this reason, the electrode is sometimes referred to as an electrode catalyst layer), and the electrode catalyst layer on the fuel electrode side generates protons and electrons from the fuel gas. Water is generated from oxygen, protons and electrons in the electrode catalyst layer on the air electrode side, and the solid polymer electrolyte membrane conducts protons in ionic conduction. And electric power is taken out through this electrode catalyst layer.

  Conventionally, in a polymer electrolyte fuel cell, a perfluoroalkyl sulfonic acid polymer represented by Nafion (trademark) is used as an electrolyte of an electrode catalyst layer. Although this material has excellent proton conductivity, it is very expensive and has a large amount of fluorine atoms in the molecule, so that it has low combustibility and is used for the electrode catalyst such as platinum. There is a problem that makes it very difficult to recover and reuse expensive precious metals.

  On the other hand, various non-perfluoroalkylsulfonic acid polymers have been studied as alternative materials. In particular, an attempt has been made to use an aromatic sulfonic acid polymer having a high heat resistance as an electrolyte with the aim of using it under high temperature conditions with high power generation efficiency.

For example, Japanese Patent Application Laid-Open No. 2005-50726 (Patent Document 1) discloses the use of a sulfonated polyarylene polymer as an electrode electrolyte, and further, Japanese Patent Application Laid-Open No. 2004-253267 (Patent Document 2). Discloses the use of certain sulfonated polyarylenes.
Japanese Patent Laying-Open No. 2005-50726 JP 2004-253267 A

  However, these materials conventionally known as electrolytes sometimes cause a reversible elimination reaction of sulfonic acid groups or a crosslinking reaction involving sulfonic acid at high temperatures. As a result, there is a problem that proton conductivity is reduced, membrane embrittlement or the like occurs, power generation output of the fuel cell is reduced, or power generation is disabled when the membrane is broken.

In order to avoid such problems as much as possible, the upper limit temperature at the time of fuel cell power generation is limited and used, and the power generation output is limited.
When the sulfonic acid concentration is increased in order to increase proton conductivity, there is a problem that the swelling due to water absorption is large under high-temperature and high-humidity conditions, the gas flow path is blocked, and the power generation performance decreases.

  That is, the object of the present invention is to solve the above-mentioned problem of cost and the problem of recovery of the catalytic metal, and is a solid having excellent proton conductivity, dimensional stability, resistance to hot water, and mechanical properties. Provided is an electrode electrolyte for a polymer fuel cell, and further provides an electrode paste, an electrode, and an electrolyte membrane with a catalyst containing the electrolyte.

  The present invention has been made in order to solve the above-described problems. By using a specific polyarylene polymer, a copolymer having a high sulfonic acid concentration can be synthesized, and a material having a high proton conductivity. Design is possible, the stability of sulfonic acid groups under high temperature conditions can be improved, and even if the composition ratio of units having no sulfonic acid groups in the copolymer is increased, the copolymer of high sulfonic acid concentration It has been found that coalescence can be synthesized, material design with excellent hot water resistance and mechanical properties becomes possible, and the above problems are solved.

  Furthermore, this polymer does not contain a fluorine atom, or even if it contains it, its content has been greatly reduced, and it has been found that the above-mentioned problems relating to the recovery and reuse of catalyst metals can be solved. It came to be completed.

The configuration of the present invention is as follows.
[1] An electrode electrolyte for a polymer type fuel cell, comprising a polyarylene copolymer containing a structural unit represented by the general formula (1).

Wherein (1), A, D, E is a direct bond, -O -, - S -, - CO -, - SO 2 -, - SO-
, —CONH—, —COO—, — (CF ₂ ) _f — (f is an integer of 1 to 10), — (CH ₂ ) _h — (h is an integer of 1 to 10), —CR ′ _2- (R ′ represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group and a halogenated hydrocarbon group), at least one structure selected from the group consisting of a cyclohexylidene group and a fluorenylidene group.

B independently represents an oxygen atom or a sulfur atom, and X represents an atom or group selected from a halogen atom excluding fluorine, —OSO ₂ CH ₃ and —OSO ₂ CF ₃ .
R _{1 to} R ₂₈ may be the same as or different from each other, and may be a hydrogen atom, a fluorine atom, an alkyl group, a halogenated alkyl group in which some or all are halogenated, an allyl group, an aryl group, a nitro group, and a nitrile group. At least one atom or group selected from the group consisting of

l and o represent an integer of 0 to 4, m represents an integer of 1 to 4, and q represents an integer of 2 or more. n and p indicate the composition ratio of each unit and take a value of 0 to 1, where n + p = 1. However, n takes a value other than 0. ]
[2] The polymer electrolyte fuel cell electrode electrolyte according to [1], wherein the structural unit represented by the formula (1) is a structural unit represented by the following general formula (2).

Wherein (2), A, E is a direct bond, -O -, - CO -, - SO 2 -, - SO -, - (CF 2) f
- (f is an integer of 1 to _{10), - (CH 2) h} - (h is an integer of 1 to _{10), - CR '2 - (} R' is an aliphatic hydrocarbon group, an aromatic hydrocarbon A hydrogen group and a halogenated hydrocarbon group), at least one structure selected from the group consisting of a cyclohexylidene group and a fluorenylidene group.

D is a direct bond, —O—, —CO—, — (CH ₂ ) _h — (h is an integer of 1 to 10), —CR
" _2- (R" represents an aliphatic hydrocarbon group or aromatic hydrocarbon group), and X represents an atom selected from halogen atoms excluding fluorine. R _{1 to} R ₂₈ may be the same as or different from each other, and are selected from a hydrogen atom, a fluorine atom, an alkyl group, a halogenated alkyl group, an allyl group, an aryl group, a nitro group, and a nitrile group, which are partially or completely halogenated. At least one atom or group selected from the group consisting of: L and o each represent an integer of 0 to 4, and q represents an integer of 2 or more. n and p indicate the composition ratio of each unit and take a value of 0 to 1, where n + p = 1. However, n takes a value other than 0. ]
[3] The polymer electrolyte fuel cell electrode electrolyte of [2], which is a structural unit represented by the following general formula (3).

[In the formula (3), X represents an atom selected from halogen atoms excluding fluorine, D represents —O—, —CR ″ ₂ — (R ″ represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group; ). P is at least one structure selected from structures represented by the following general formulas (4-1) to (4-3), and Q is represented by the following general formulas (5-1) to (5-12). At least one structure selected from the following structures. Q represents an integer of 2 or more. n and p indicate the composition ratio of each unit and take a value of 0 to 1, where n + p = 1. However, n takes a value other than 0. ]

[4] The polymer electrolyte fuel cell electrode electrolyte according to [3], wherein in the general formula (3), n = 0.3 to 1.
[5] The polymer electrolyte fuel cell electrode electrolyte according to [1] to [4], wherein the polyarylene copolymer further contains a structural unit represented by the following general formula (6).

Wherein Y is —CO—, —SO ₂ —, —SO—, —CONH—, —COO—, — (CF ₂ ) _f — (l is an integer of 1 to 10), —C (CF _{3) 2} - represents at least one structure selected from the group consisting of, Z is a direct bond _{or, - (CH 2) h -} (h is an integer of 1 to 10), - C (CH _{3) 2} represents at least one structure selected from the group consisting of —, —O—, and —S—, and Ar represents —
An aromatic group having a substituent represented by SO ₃ H or —O (CH ₂ ) _r SO ₃ H or —O (CF ₂ ) _r SO ₃ H is shown. r represents an integer of 1 to 12, j represents an integer of 0 to 10, and k represents 0 to 10
I represents an integer of 1 to 4. )
[6] An electrode paste comprising the electrolyte of [1] to [5], catalyst particles, and a solvent.
[7] An electrode for a polymer electrolyte fuel cell comprising the electrolyte according to [1] to [5] and catalyst particles.
[8] A membrane-electrode assembly comprising the electrode according to [7] on at least one surface of a polymer electrolyte membrane.

According to the present invention, a structural unit having hydrophobicity derived from a compound synthesized from a monomer having three or more continuous benzene rings represented by 4,4 ′-(1,3-phenylenediisopropylidene) bisphenol Therefore, even if a sulfonic acid group is introduced at a high concentration, an electrode electrolyte having high methanol resistance, excellent workability, and high proton conductivity can be obtained. In addition, according to the present invention, there is provided an electrode electrolyte for a polymer electrolyte fuel cell that is inexpensive, easily recovers catalytic metal, has excellent proton conductivity and dimensional stability, and has excellent hot water resistance and mechanical properties. Provided. Furthermore, the present invention provides an electrode paste, an electrode, and a catalyst-attached electrolyte membrane containing the electrolyte, and contributes to improvement in power generation performance of a solid polymer fuel cell.

(Electrode electrolyte)
An electrode electrolyte for a polymer electrolyte fuel cell according to the present invention is a structural unit derived from a monomer having three or more continuous benzene rings represented by 4,4 ′-(1,3-phenylenediisopropylidene) bisphenol. A polyarylene-based copolymer.

[Polyarylene copolymer]
The polyarylene copolymer used in the present invention contains a structural unit represented by the following general formula (1). This structural unit imparts a hydrophobic portion to the polymer.

  Moreover, since it has three or more continuous benzene rings, the main chain skeleton is flexible and the heat distortion temperature can be lowered. For this reason, it has the effect | action which improves the workability at the time of fuel cell manufacture using a hot press, and joining property with an electrode.

  Since such a hydrophobic structural unit is included, a polymer electrolyte and a proton conductive membrane having high methanol resistance, excellent processability, and high proton conductivity even when a sulfonic acid group is introduced at a high concentration. Can be formed.

  In addition, in a compound having two or less continuous benzene rings, introduction of a sulfonic acid group at a high concentration may result in low methanol resistance, poor processability, and lower adhesion to electrodes and the like. is there.

  In formula (1), l and o represent an integer of 0 to 4, m represents an integer of 1 to 4, and q represents an integer of 2 or more. n and p indicate the composition ratio of each unit and take a value of 0 to 1, where n + p = 1. However, n takes a value other than 0. Of these, m is preferably 1, and l is preferably 0 or 1. Moreover, it is preferable that n takes the value of 0.3-1.

A and E are direct bonds, —O—, —S—, —CO—, —SO ₂ —, —SO—, —CONH—.
, —COO—, — (CF ₂ ) _f — (f is an integer of 1 to 10), — (CH ₂ ) _h — (h is an integer of 1 to 10), —CR ′ ₂ — (R 'Represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group or a halogenated hydrocarbon group), at least one structure selected from the group consisting of a cyclohexylidene group and a fluorenylidene group. Here, specific examples of the structure represented by —CR ′ ₂ — include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, t-butyl group, propyl group, octyl group, decyl group. Group, octadecyl group, phenyl group, trifluoromethyl group, and the like.

Among these, a direct bond or a, -O -, - CO -, - SO -, - SO 2 -, - CR '2 -, - (CF 2) f -, - (CH 2) h -, cyclohexylidene Group and fluorenylidene group are preferred.

B independently represents an oxygen atom or a sulfur atom, preferably an oxygen atom.
D is a direct bond, —O—, —S—, —CO—, —SO ₂ —, —SO—, —CONH—,
—COO—, — (CF ₂ ) _f — (f is an integer of 1 to 10), — (CH ₂ ) _h — (h is an integer of 1 to 10), —CR ′ ₂ — (R ′ Represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group and a halogenated hydrocarbon group), and represents at least one structure selected from the group consisting of a cyclohexylidene group and a fluorenylidene group. Here, specific examples of the structure represented by —CR ′ ₂ — include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, t-butyl group, propyl group, octyl group, decyl group. Group, octadecyl group, phenyl group, trifluoromethyl group, and the like. Of these, direct bond, -O-, -SO-,-(C
H ₂ ) _h — and —CR ″ ₂ — (R ″ represents an aliphatic hydrocarbon group or an aromatic hydrocarbon group) are preferred.

X represents a halogen atom excluding fluorine, an atom or group selected from —OSO ₂ CH ₂ and —OSO ₂ CF _2, and a halogen atom excluding fluorine is particularly preferably Cl or Br.
R _{1 to} R ₂₈ may be the same as or different from each other, and may be a hydrogen atom, a fluorine atom, an alkyl group, a halogenated alkyl group in which some or all are halogenated, an allyl group, an aryl group, a nitro group, and a nitrile group. At least one atom or group selected from the group consisting of

  As the structural unit, a structural unit represented by the following (2) is preferable.

Wherein (2), A, E is a direct bond, -O -, - CO -, - SO 2 -, - SO -, - (CF 2) f
- (f is an integer of 1 to _{10), - (CH 2) h} - (h is an integer of 1 to _{10), - CR '2 - (} R' is an aliphatic hydrocarbon group, an aromatic hydrocarbon A hydrogen group and a halogenated hydrocarbon group), at least one structure selected from the group consisting of a cyclohexylidene group and a fluorenylidene group.

D is a direct bond, —O—, —CO—, — (CH ₂ ) _h — (h is an integer of 1 to 10), —CR
" _2- (R" represents an aliphatic hydrocarbon group or aromatic hydrocarbon group), and X represents an atom selected from halogen atoms excluding fluorine. R _{1 to} R ₂₈ may be the same as or different from each other, and are selected from a hydrogen atom, a fluorine atom, an alkyl group, a halogenated alkyl group, an allyl group, an aryl group, a nitro group, and a nitrile group, which are partially or completely halogenated. At least one atom or group selected from the group consisting of: L and o each represent an integer of 0 to 4, and q represents an integer of 2 or more. n and p indicate the composition ratio of each unit and take a value of 0 to 1, where n + p = 1. However, n takes a value other than 0. ]
As the structural unit, a compound represented by the following formula (3) is more preferable.

[In the formula (3), X represents an atom selected from halogen atoms excluding fluorine, D represents —O—, —CR ″ ₂ — (R ″ represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group; ). P is at least one structure selected from the structures represented by the following general formulas (4-1) to (4-3), and Q is the following general formula. Q represents an integer of 2 or more. n and p indicate the composition ratio of each unit and take a value of 0 to 1, where n + p = 1. However, n takes a value other than 0. ]

  The structural unit represented by the above formula (1) is derived from a monomer represented by the following formula (1 ′).

In the formula (1 ′), each symbol and a preferable range are the same as those of the structural unit represented by the formula (1). Such a monomer can be synthesized, for example, by the following reaction.

First, in order to convert a divalent atom or organic group or a bisphenol linked by a direct bond into an alkali metal salt of the corresponding bisphenol, N-methyl-2-pyrrolidone, N,
In polar solvents with high dielectric constant such as N-dimethylacetamide, sulfolane, diphenylsulfone, dimethylsulfoxide, alkali metals such as lithium, sodium and potassium, alkali metal hydrides, alkali metal hydroxides, alkali metal carbonates, etc. Add The alkali metal is reacted in excess with respect to the hydroxyl group of phenol, and is usually used in an amount of 1.1 to 2 times equivalent, preferably 1.2 to 1.5 times equivalent. At this time, it is preferable to promote the progress of the reaction by coexisting a solvent azeotropic with water such as benzene, toluene, xylene, chlorobenzene, and anisole.

Next, the alkali metal salt of bisphenol is reacted with a dihalide compound substituted with a halogen atom such as chlorine and a nitrile group.
Among the above bisphenols, those having three or more continuous benzene rings include 4,4 ′-(1,3-phenylenediisopropylidene) bisphenol and 4,4 ′-(1,4-phenylenediisopropylidene) bisphenol. 1,3- (4-hydroxybenzoylbenzene), 1,4- (4-hydroxybenzoylbenzene), 1,3-bis (4-hydroxyphenoxy) benzene, 1,4-bis (4-hydroxyphenoxy) benzene 1,4-bis (4-hydroxyphenyl) benzene, 1,3-bis (4-hydroxyphenyl) benzene, and the like. Of these, 4,4 ′-(1,3-phenylenediisopropylidene) bisphenol and 4,4 ′-(1,4-phenylenediisopropylidene) bisphenol are preferable.

Other bisphenols include 4,4′-isopropylidenebiphenol, 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane, and 4,4′-bis. Hydroxybenzophenone, 4,4′-bishydroxydiphenyl sulfone, 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxybiphenyl, bis (4-hydroxyphenyl) methane, resorcinol, hydroquinone, 2,6-dihydroxynaphthalene, 9 , 9-bis (4-hydroxyphenyl) fluorene, 4,4′-isopropylidenebis (2-phenylphenol), 4,4′-cyclohexylidenebis (2-cyclohexylphenol), and the like.

  Examples of the dihalogen compound include 4,4′-dichlorobenzophenone, 4,4′-difluorobenzophenone, 4-chloro-4′-fluorobenzophenone, 2-chloro-4′-fluorobenzophenone, 4,4′-dichlorodiphenylsulfone. 4,4′-difluorodiphenylsulfone, 2,6-dinitrobenzonitrile, 2,5-dinitrobenzonitrile, 2,4-dinitrobenzonitrile, 2,6-dichlorobenzonitrile, 2,5-dichlorobenzonitrile, Examples include 2,4-dichlorobenzonitrile, 2,6-difluorobenzonitrile, 2,5-difluorobenzonitrile, 2,4-difluorobenzonitrile, 2-chloro-6-fluorobenzonitrile and the like.

  The dihalogen compound is used in an amount of 1.0001 to 1 mol, preferably 1.001 to 2 mol based on bisphenol. Further, after the completion of the reaction, for example, an excess of a dichloro compound may be further reacted so that both ends are chlorine atoms. When a difluoro compound or a dinitro compound is used, it is necessary to devise the reaction so that both ends are chlorine atoms by a method such as adding a dichloro compound in the latter half of the reaction.

These reactions are performed at a reaction temperature of 60 ° C to 300 ° C, preferably in the range of 80 ° C to 250 ° C, and in a reaction time of 15 minutes to 100 hours, preferably in the range of 1 hour to 24 hours.
The obtained oligomer or polymer can be purified by a general polymer purification method, for example, a dissolution-precipitation operation. The molecular weight is adjusted by the reaction molar ratio of excess aromatic dichloride and bisphenol. Since the aromatic dichloride is excessive, the molecular ends of the obtained oligomer or polymer are aromatic chlorides.

  Specific examples of the compound synthesized by the above method include the following.

  Among these compounds, a compound synthesized from 4,4 ′-(1,3-phenylenediisopropylidene) bisphenol and 4,4 ′-(1,4-phenylenediisopropylidene) bisphenol is preferable. .

The glass transition temperature of the polymer can be adjusted by changing the ratio of n and p representing the composition ratio of each unit. Among these, from the viewpoint of polymer processability, compounds having a value of n = 0.3 to 1 are useful. In this range, the main chain skeleton is flexible, so the thermal deformation temperature is low, and therefore it is possible to improve the workability and the bondability with the electrode when manufacturing a fuel cell using a hot press. Become. Furthermore, since it contains a structural unit having a hydrophobic property derived from such an aromatic compound, even when a sulfonic acid group is introduced at a high concentration, the electrode electrolyte has high methanol resistance, excellent workability, and high proton conductivity. Can be formed.

The structural unit contained as an essential component in the polyarylene copolymer used in the present invention is a monomer in which the terminal x is removed in such a monomer.
In addition to the structural unit (1), the electrode electrolyte of the present invention includes a structural unit that provides proton conductivity.

As such a proton conductive structural unit, a structural unit (sulfonic acid unit) having a sulfonic acid group represented by the following general formula (A) is preferable.
<Sulphonic acid unit>

In the general formula (A), Y represents —CO—, —SO ₂ —, —SO—, —CONH—, —COO.
It represents at least one structure selected from the group consisting of —, — (CF ₂ ) ₁ — (wherein 1 is an integer of 1 to 10) and —C (CF ₃ ) ₂ —. Of these, —CO— and —SO ₂ — are preferable.

Z is a direct bond or at least one selected from the group consisting of — (CH ₂ ) ₁ — (wherein 1 is an integer of 1 to 10), —C (CH ₃ ) ₂ —, —O—, and —S—. The structure of the species is shown. Among these, a direct bond and -O- are preferable.

Ar is an aromatic group having a substituent represented by —SO ₃ H or —O (CH ₂ ) _p SO ₃ H or —O (CF ₂ ) _p SO ₃ H (p represents an integer of 1 to 12). Indicates.
Specific examples of the aromatic group include a phenyl group, a naphthyl group, an anthryl group, and a phenanthryl group. Of these groups, a phenyl group and a naphthyl group are preferable. -SO ₃
A substituent represented by H or —O (CH ₂ ) _p SO ₃ H or —O (CF ₂ ) _p SO ₃ H (p is 1 to 1
2 represents an integer of 2), it is necessary that at least one is substituted, and in the case of a naphthyl group, two or more are preferably substituted.

j is an integer of 0 to 10, preferably 0 to 2, k is an integer of 0 to 10, preferably 0 to 2, and i is an integer of 1 to 4.
As a preferred combination of the values of j and k and the structures of Y, Z and Ar, (1) j = 0, k = 0, Y is —CO—, and Ar is substituted with —SO ₃ H. (2) j = 1, k = 0, Y is —CO—, Z is —O—, and Ar is a phenyl group having —SO ₃ H as a substituent. A certain structure, (3) j = 1, k = 1, i = 1
Y is —CO—, Z is —O—, Ar is a phenyl group having —SO ₃ H as a substituent, (4) j = 1, k = 0, Y Is —CO—, Z is —O—, and Ar is a naphthyl group having two —SO ₃ H as a substituent, (5) j =
1, k = 0, Y is —CO—, Z is —O—, and Ar is —O (
CH _2), such as structure that is a phenyl group having a ₄ SO ₃ H and the like.

The polyarylene having a sulfonic acid group suitably used as an electrode electrolyte is specifically a polymer represented by the following general formula (C).
<Polymer structure>

In the general formula (C), A, B, D, E, Y, Z, Ar, i, k, j, l, m, n, o, p, q, and R _{1 to} R ₂₈ are each the above general formula. A, B, D, E, Y in (1) and (A)
, Z, Ar, i, k, j, l, m, n, o, p, q and R _{1 to} R ₂₈ . x,
y represents the molar ratio when x + y = 100 mol%.

  The polyarylene having a sulfonic acid group used in the present invention is a proportion of 0.5 to 99.999 mol%, preferably 10 to 99.9 mol% of the structural unit represented by the formula (A), that is, the unit of x. The structural unit represented by the formula (B), that is, the unit of y is contained in a proportion of 99.5 to 0.001 mol%, preferably 90 to 0.1 mol%.

The polyarylene polymer has a polystyrene-equivalent weight average molecular weight (hereinafter simply referred to as “weight average molecular weight”) measured by gel permeation chromatography is 10,000 to 1,000,000, preferably 20,000 to 800,000.
<Method for producing polymer>
For the production of polyarylene having a sulfonic acid group, for example, the following three methods, Method A, Method B and Method C, can be used.

(Method A)
For example, in the method described in JP-A No. 2004-137444, a monomer having a sulfonate group that can be a structural unit represented by the general formula (A), and a structural unit represented by the general formula (1) A polyarylene having a sulfonic acid ester group is produced by copolymerization with a monomer or oligomer that can be synthesized, and the sulfonic acid ester group is deesterified, and then the sulfonic acid ester group is converted into a sulfonic acid group. be able to.

(Method B)
For example, in the method described in JP-A-2001-342241, a monomer having a skeleton represented by the general formula (A) and not having a sulfonic acid group or a sulfonic acid ester group, and the general formula (1) It is also possible to synthesize this polymer by copolymerizing a monomer or oligomer that can be a structural unit represented and sulfonating the polymer using a sulfonating agent.

(Method C)
In the general formula (A), when Ar is an aromatic group having a substituent represented by —O (CH ₂ ) _p SO ₃ H or —O (CF ₂ ) _p SO ₃ H, for example, A precursor monomer that can be the structural unit represented by the general formula (A) and a monomer or oligomer that can be the structural unit represented by the general formula (1) by the method described in JP-A-2005-60625 Can be synthesized by a method in which an alkylsulfonic acid or a fluorine-substituted alkylsulfonic acid is introduced.
As specific examples of the monomer having a sulfonic acid ester group that can be used in (Method A) and can be the structural unit represented by the general formula (A), JP-A Nos. 2004-137444 and 2004-345997 are disclosed. Examples thereof include sulfonic acid esters described in JP-A-2004-346163.
As a specific example of a monomer having no sulfonic acid group or sulfonic acid ester group that can be a structural unit represented by the above general formula (A) that can be used in (Method B), JP-A-2001-342241 Examples thereof include dihalides described in Japanese Patent Laid-Open No. 2002-293889.
Specific examples of precursor monomers that can be used in (Method C) and can be structural units represented by the above general formula (A) include dihalides described in JP-A-2005-36125. Can be mentioned.

In addition, the precursor which can be a structural unit represented by the general formula (1) is a monomer represented by the formula (1 ′) as described above.
In order to obtain a polyarylene having a sulfonic acid group, first, a monomer that can be a structural unit represented by the general formula (A), a monomer that can be a structural unit represented by the general formula (1), Alternatively, it is necessary to copolymerize with an oligomer to obtain a precursor polyarylene. This copolymerization is carried out in the presence of a catalyst, and the catalyst used in this case is a catalyst system containing a transition metal compound. This catalyst system is (1) a transition metal salt and a ligand. A compound (hereinafter referred to as “ligand component”) or a transition metal complex coordinated with a ligand (including a copper salt) and (2) a reducing agent as essential components, and further increase the polymerization rate. Therefore, “salt” may be added.

  Specific examples of these catalyst components, the use ratio of each component, the polymerization conditions such as the reaction solvent, concentration, temperature, time, etc. include the compounds described in JP-A No. 2001-342241.

The polyarylene having a sulfonic acid group can be obtained by converting the precursor polyarylene to a polyarylene having a sulfonic acid group. As this method, there are the following three methods.
(Method A) A method of deesterifying a polyarylene having a sulfonic acid ester group as a precursor by the method described in JP-A-2004-137444.
(Method B) A method of sulfonating a precursor polyarylene by the method described in JP-A-2001-342241.
(Method C) A method of introducing an alkylsulfonic acid group into the precursor polyarylene by the method described in JP-A-2005-60625.

  The polyarylene having a sulfonic acid group of the general formula (C) produced by the above method has an ion exchange capacity of usually 0.3 to 5 meq / g, preferably 0.5 to 3 meq / g, more preferably Is 0.8 to 2.8 meq / g. If it is less than 0.3 meq / g, the proton conductivity is low and the power generation performance is low. On the other hand, if it exceeds 5 meq / g, the water resistance may be significantly lowered, which is not preferable.

  The ion exchange capacity is, for example, a precursor monomer that can be a structural unit represented by the general formula (A), a monomer that can be a structural unit represented by the general formula (1), or the kind of oligomer, and a use ratio. It can be adjusted by changing the combination. Specifically, the monomer ratio may be changed so that the composition ratio is as described above.

  The molecular weight of the polyarylene having a sulfonic acid group thus obtained is 10,000 to 1,000,000, preferably 20,000 to 800,000 in terms of polystyrene-equivalent weight average molecular weight by gel permeation chromatography (GPC).

  Such a polyarylene polymer can be synthesized by introducing a specific aromatic group so that a copolymer having a high sulfonic acid concentration can be synthesized, and a material design with high proton conductivity can be achieved. In addition to improving the stability of the sulfonic acid group, it is possible to synthesize a copolymer having a high sulfonic acid concentration even if the composition ratio of units having no sulfonic acid group in the copolymer is increased. Material design with excellent mechanical properties is possible. Such a polymer can be suitably used as a proton conductive membrane, an electrode electrolyte, and a binder for a fuel cell. An electrode electrolyte containing such a polyarylene polymer is also suitable as a membrane electrode assembly.

The electrode electrolyte according to the present invention only needs to include the above-described polymer, and therefore, the electrode electrolyte may be composed of only the above-described polymer or may further include another electrolyte. Other electrolytes include perfluorocarbon polymers such as Nafion, Flemion, and Aciplex that have been used in the past, sulfonated products of vinyl polymers such as polystyrene sulfonic acid, polybenzimidazole, polyether ether ketone, and other heat resistance Examples of the polymer include organic polymers such as a polymer in which a sulfonic acid group or a phosphoric acid group is introduced. When other electrolytes are included, the ratio of use is desirably 50% by weight or less, preferably 30% by weight in the total electrode electrolyte.
(Electrode paste)
The electrode paste of the present invention is composed of the above-mentioned electrode electrolyte, catalyst particles, and solvent, and may contain other components such as a dispersant and carbon fiber as necessary.
Catalyst particles The catalyst particles are composed of a catalyst supported on carbon or a metal oxide support, or a single catalyst.

  Platinum or a platinum alloy is used as the catalyst. When a platinum alloy is used, stability and activity as an electrode catalyst can be further imparted. Such platinum alloys include platinum group metals other than platinum (ruthenium, rhodium, palladium, osmium, iridium), iron, cobalt, titanium, gold, silver, chromium, manganese, molybdenum, tungsten, aluminum, silicon, rhenium. An alloy of platinum and one or more selected from zinc and tin is preferable, and the platinum alloy may contain an intermetallic compound of a metal alloyed with platinum.

The catalyst forms catalyst particles, either alone or supported on a carrier.
As the carrier for supporting the catalyst, carbon black such as oil furnace black, channel black, lamp black, thermal black and acetylene black is preferably used in view of the electron conductivity and the specific surface area. Further, artificial graphite or carbon obtained from organic compounds such as natural graphite, pitch, coke, polyacrylonitrile, phenol resin, furan resin, and the like may be used.

  Examples of the oil furnace black include “Vulcan XC-72”, “Vulcan P”, “Black Pearls 880”, “Black Pearls 1100”, “Black Pearls 1300”, “Black Pearls 2000”, and “Regal 400” manufactured by Cabot Corporation. “Ketjen Black EC” manufactured by Lion Corporation, “# 3150, # 3250” manufactured by Mitsubishi Chemical Corporation, and the like. Examples of the acetylene black include “DENKA BLACK” manufactured by Denki Kagaku Kogyo.

As the form of these carbons, in addition to particles, fibers can also be used. Further, the amount of the catalyst supported on the carbon is not particularly limited as long as the catalyst activity can be effectively exhibited, but the supported amount is 0.1 to 9.0 g- with respect to the carbon weight. Metal / g-carbon, preferably in the range of 0.25 to 2.4 g-metal / g-carbon.

  In addition to carbon, the carrier may be a metal oxide such as titania, zinc oxide, silica, ceria, alumina, alumina spinel, magnesia, zirconia, and the like.

Solvent The solvent of the electrode paste of the present invention is not particularly limited as long as it can dissolve or disperse the electrolyte. Further, not only one type but also two or more types of solvents can be used.

Specifically, water,
Methanol, ethanol, n-propyl alcohol, 2-propanol, 2-methyl-2-propanol, 2-butanol, n-butyl alcohol, 2-methyl-1-propanol, 1-pentanol, 2-pentanol, 3- Pentanol, 2-methyl-1-butanol, 3-methyl-1-butanol, 2-methyl-2-butanol, 3-methyl-2-butanol, 2,2-dimethyl 1-propanol, cyclohexanol, 1-hexanol 2-methyl-1-pentanol, 2-methyl-2-pentanol, 4-methyl-2-pentanol, 2-ethyl-1-butanol, 1-methylcyclohexanol, 2-methylcyclohexanol, 3- Methylcyclohexanol, 4-methylcyclohexanol, 1-octanol, 2-octa Nord, 2-ethyl-1-hexanol, 2-methoxyethanol, 2-ethoxyethanol, 2- (methoxymethoxy) ethanol, 2-isopropoxyethanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, Alcohols such as
Polyhydric alcohols such as ethylene glycol, propylene glycol and glycerol,
Dioxane, tetrahydrofuran, tetrahydropyran, diethyl ether, diisopropyl ether, di-n-propyl ether, butyl ether, phenyl ether, isopentyl ether, 1,2-dimethoxyethane, diethoxyethane, bis (2-methoxyethyl) ether, bis Ethers such as (2-ethoxyethyl) ether, cineol, benzyl ethyl ether, anisole, phenetole, acetal,
Ketones such as acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone, cyclopentanone, cyclohexanone, 2-hexanone, 4-methyl-2-pentanone, 2-heptanone, 2,4-dimethyl-3-pentanone, 2-octanone Kind,
γ-butyrolactone, ethyl acetate, propyl acetate, n-butyl acetate, isobutyl acetate, sec-butyl acetate, pentyl acetate, isopentyl acetate, 3-methoxybutyl acetate, methyl butyrate, ethyl butyrate, methyl lactate, ethyl lactate, lactic acid Esters such as butyl,
Aprotic polar solvents such as dimethyl sulfoxide, N-methylformamide, N, N-dimethylformamide, N, N-diethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, tetramethylurea,
Examples thereof include hydrocarbon solvents such as toluene, xylene, heptane, hexane, heptane, and octane, and these can be used in combination of one or more.

Dispersants Dispersants that may be included as necessary include oleic acid / N-methyltaurine, potassium oleate / diethanolamine salt, alkyl ether sulfate / triethanolamine salt, polyoxyethylene alkyl ether sulfate / triethanolamine salt , Amine salt of special modified polyether ester acid, amine salt of higher fatty acid derivative, amine salt of special modified polyester acid, amine salt of high molecular weight polyether ester acid, amine salt of special modified phosphoric acid ester, high molecular weight polyester acid amidoamine salt , Amidoamine salts of special fatty acid derivatives, alkylamine salts of higher fatty acids, amidoamine salts of high molecular weight polycarboxylic acids, sodium laurate, sodium stearate, sodium oleate sodium lauryl sulfate, Chyl sulfate sodium salt, stearyl sulfate sodium salt, oleyl sulfate sodium salt, lauryl ether sulfate ester salt, sodium alkylbenzene sulfonate, oil-soluble alkylbenzene sulfonate, α-olefin sulfonate, higher alcohol phosphate monoester di Anionic surfactants such as sodium salt, higher alcohol phosphate diester disodium salt, zinc dialkyldithiophosphate, benzyldimethyl {2- [2- (P-1,1,3,3-tetramethylbutylphenoxy) ethoxy] Ethyl} ammonium chloride, octadecylamine acetate, tetradecylamine acetate, octadecyltrimethylammonium chloride, tallow trimethylammonium chloride, dodecyltrimethylammonium Chloride, palm trimethylammonium chloride, hexadecyltrimethylammonium chloride, behenyltrimethylammonium chloride, palm dimethylbenzylammonium chloride, tetradecyldimethylbenzylammonium chloride, octadecyldimethylbenzylammonium chloride, dioleyldimethylammonium chloride, 1-hydroxyethyl-2- Beef tallow imidazoline quaternary salt, 2-heptadecenyl-hydroxyethyl imidazoline,
Stearamide ethyl diethylamine acetate, stearamide ethyl diethylamine hydrochloride, triethanolamine monostearate formate, alkyl pyridium salt, higher alkyl amine ethylene oxide adduct, polyacrylamide amine salt, modified polyacrylamide amine salt, perfluoroalkyl Cationic surfactants such as quaternary ammonium iodide, and dimethyl coconut betaine, dimethyl lauryl betaine, sodium laurylaminoethylglycine, sodium laurylaminopropionate, stearyl dimethyl betaine, lauryl dihydroxyethyl betaine, amide betaine, imidazolinium betaine , Lecithin, sodium 3- [ω-fluoroaccanoyl-N-ethylamino] -1-propanesulfonate, N- [3- (perfluoro Octanesulfonamido) propyl] -N, N-dimethyl-N-carboxymethyleneammonium betaine and the like, coconut fatty acid diethanolamide (1: 2 type), coconut fatty acid diethanolamide (1: 1 type), cow Fatty acid diethanolamide (1: 2 type), bovine fatty acid diethanolamide (1: 1 type), oleic acid diethanolamide (1: 1 type), hydroxyethyl lauryl amine, polyethylene glycol lauryl amine, polyethylene glycol coconut amine, polyethylene glycol stearyl Amine, polyethylene glycol beef tallow amine, polyethylene glycol beef tallow propylene diamine, polyethylene glycol dioleyl amine, dimethyl lauryl amine oxide, dimethyl stearyl amine oxide, dihydroxy Ethyl lauryl amine oxide, perfluoroalkylamine oxide, polyvinyl pyrrolidone, higher alcohol ethylene oxide adduct, alkylphenol ethylene oxide adduct, fatty acid ethylene oxide adduct, polypropylene glycol ethylene oxide adduct, fatty acid ester of glycerin, fatty acid of pentaerythritol Nonionic surfactants such as esters, fatty acid esters of sorbitol, fatty acid esters of sorbitan, fatty acid esters of sugar, and amphoteric surfactants such as sodium laurylaminopropionate, stearyldimethylbetaine, lauryldihydroxyethylbetaine, etc. Can do. These can be used alone or in combination of two or more. Among these, a surfactant having a basic group is preferable, an anionic or cationic surfactant is more preferable, and a surfactant having a molecular weight of 5,000 to 30,000 is more preferable. is there.

When the above dispersant is added to the electrode paste, the storage stability and fluidity are excellent, and the productivity during coating is improved.
Carbon fiber In the electrode paste according to the present invention, a carbon fiber on which a catalyst is not supported can be added as necessary.

As carbon fibers used as necessary in the present invention, rayon-based carbon fibers, PAN-based carbon fibers, lignin pover-based carbon fibers, pitch-based carbon fibers, vapor-grown carbon fibers, and the like can be used, preferably Vapor grown carbon fiber.

  When carbon fiber is added to the electrode paste, the pore volume in the electrode increases, thereby improving the diffusibility of fuel gas and oxygen gas, and improving the flooding caused by the generated water, thereby improving the power generation performance. .

Other Additives In the electrode paste according to the present invention, other components can be added as necessary. For example, a water repellent such as a fluorine polymer or a silicon polymer may be added. The water repellent has an effect of efficiently discharging generated water and contributes to improvement of power generation performance.

Composition The usage ratio of the catalyst particles in the paste according to the present invention is 1 to 20% by weight, preferably 3 to 15% by weight. Further, the usage ratio of the electrode electrolyte is 0.5 to 30% by weight, and preferably 1 to 15% by weight. Further, the ratio of the solvent used is 5 to 95% by weight, preferably 15 to 90% by weight.

The use ratio of the dispersant used as necessary is 0% by weight to 10% by weight, preferably 0% by weight to 2% by weight, and the use ratio of the carbon fiber used as necessary is The ratio is 0 to 20% by weight, preferably 1 to 10% by weight. (The total amount does not exceed 100% by weight)
When the use ratio of the catalyst particles is less than the above range, the electrode reaction rate may be lowered. On the other hand, if it is larger than the above range, the viscosity of the electrode paste increases and uneven coating may occur during coating.

  When the use ratio of the electrolyte is less than the above range, the proton conductivity decreases. Furthermore, it cannot play the role of a binder, and an electrode cannot be formed. Moreover, when larger than the said range, the pore volume in an electrode will reduce.

When the use ratio of the solvent is within the above range, a sufficient pore volume in the electrode necessary for power generation can be secured. Moreover, if it exists in the said range, it is suitable for the handling as a paste.
When the use ratio of the dispersant is within the above range, an electrode paste having excellent storage stability can be obtained. When the use ratio of the carbon fiber is less than the above range, the effect of increasing the pore volume in the electrode is low. Moreover, when larger than the said range, an electrode reaction rate may fall.

Preparation of Paste The electrode paste according to the present invention can be prepared , for example, by mixing the above-mentioned components at a predetermined ratio and kneading by a conventionally known method.

The order of mixing each component is not particularly limited. For example, all components are mixed and stirred for a certain period of time, or components other than the dispersant are mixed and stirred for a certain period of time, and then a dispersant is added as necessary. It is preferable to add and stir for a certain time. Moreover, you may adjust the quantity of a solvent as needed and may adjust the viscosity of a paste.
(Electrode membrane with electrode and catalyst)
When the electrode paste according to the present invention as described above is applied onto a transfer substrate and the solvent is removed, the electrode of the present invention is obtained.

  As the transfer substrate, a sheet made of a fluoropolymer such as polytetrafluoroethylene (PTFE), a glass plate or a metal plate whose surface is treated with a release agent, a polyethylene terephthalate (PET) sheet, or the like can be used.

Examples of the coating method include brush coating, brush coating, bar coater coating, knife coater coating, doctor blade method, screen printing, and spray coating.
When the electrode applied on the transfer substrate is dried to remove the solvent and then transferred to both surfaces of the solid polymer electrolyte membrane, the electrolyte membrane with catalyst of the present invention is obtained.

The solid polymer electrolyte membrane used for the catalyst-attached electrolyte membrane of the present invention is not particularly limited as long as it is a proton conductive solid polymer membrane.
For example, an electrolyte membrane made of a perfluoroalkyl sulfonic acid polymer such as Nafion (DuPont), Flemion (Asahi Glass), Aciplex (Asahi Kasei),
Reinforced electrolyte membrane combined with polytetrafluoroethylene fiber and porous membrane to perfluoroalkylsulfonic acid polymer,
An electrolyte membrane comprising a partially fluorinated sulfonated polymer such as polytetrafluoroethylene graft sulfonated polystyrene,
Sulfonated polyarylene, sulfonated polyphenylene, sulfonated polyether ketone, sulfonated polyether sulfone, sulfonated polyether nitrile, sulfonated polyphenylene ether, sulfonated polyphenylene sulfide, sulfonated polybenzimidazole, sulfonated polybenzoxazole, sulfone Electrolyte membranes made of aromatic sulfonated polymers such as modified polybenzthiazole,
Electrolyte membranes composed of aliphatic sulfonated polymers such as sulfonated polystyrene and sulfonic acid-containing acrylic polymers,
A pore filling type electrolyte membrane in which these are combined with a porous membrane,
Examples thereof include an electrolyte membrane made of an acid-impregnated polymer in which a polymer such as polybenzoxazole, polybenzimidazole, or polybenzthiazole is impregnated with phosphoric acid or sulfuric acid. Among these, an electrolyte membrane made of an aromatic sulfonated polymer is preferable.

Moreover, the polymer which comprises the said electrolyte for electrodes can also be used as a solid polymer electrolyte.
In order to transfer the electrode to the solid polymer electrolyte membrane, a hot press method can be used. In the hot press method, the electrode paste is applied to carbon paper or a release sheet, but the electrode paste application surface and the electrolyte membrane are pressure-bonded. Hot pressing is usually performed in a temperature range of 50 to 250 ° C. and a pressure of 10 to 500 kg / cm ² for a period of 1 minute to 180 minutes.

As another method for obtaining the catalyst-attached electrolyte membrane of the present invention, there is a method of repeatedly applying and drying the catalyst layer and the electrolyte membrane stepwise. There is no restriction | limiting in particular in the order of application | coating and drying.
For example, an electrolyte membrane solution is applied on a substrate such as a PET film and dried to form an electrolyte membrane, and then the electrode paste of the present invention is applied thereon. Next, the substrate is peeled off, and the electrode paste is applied to the other surface. Finally, when the solvent is removed, an electrolyte membrane with catalyst is obtained. Examples of the application method include the same methods as described above.

The solvent is removed at a drying temperature of 20 ° C. to 180 ° C., preferably 50 ° C. to 160 ° C., and a drying time of 5 minutes to 600 minutes, preferably 30 minutes to 400 minutes.
If necessary, the electrolyte membrane may be immersed in water to remove the solvent. Water temperature is 5 to 120 ° C
The immersion time in water is preferably 1 minute to 72 hours, preferably 5 minutes to 48 hours.

  Contrary to the above method, the electrode paste is first applied and the electrode layer is formed, and then the electrolyte membrane solution is applied to create the electrolyte membrane, and then the other catalyst layer is applied. It is good also as an electrolyte membrane with a catalyst by drying.

The thickness of the electrode layer is not particularly limited, but the metal supported as a catalyst is 0.05 to 4.0 mg / cm ² , preferably 0.1 to 2.0 mg / cm ² per unit area. It is desirable to be in the range of ² . Within this range, sufficiently high catalytic activity is exhibited and protons can be efficiently conducted.

  The pore volume of the electrode layer is 0.05 to 3.0 ml / g, preferably 0.1 to 2.0 ml / g. The pore volume of the electrode layer is measured by a method such as a mercury intrusion method or a gas adsorption method.

The thickness of the electrolyte membrane is not particularly limited, but if the thickness is increased, the power generation efficiency is reduced or it is difficult to reduce the weight, so that the thickness may be about 10 to 200 μm. is not.
[Example]
EXAMPLES Hereinafter, although this invention is demonstrated further more concretely based on an Example, this invention is not limited to these Examples. Various measurement items in the examples were determined as follows.
(Molecular weight)
As for the molecular weight of the polymer, a polystyrene-reduced weight average molecular weight was determined by GPC. N-methyl-2-pyrrolidone to which lithium bromide was added was used as a solvent.
(Ion exchange capacity)
The obtained sulfonated polymer is washed until the washing water has a pH of 4 to 6, the free remaining acid is removed, washed thoroughly, dried, weighed, and mixed with THF / water. After dissolving in a solvent, phenolphthalein was used as an indicator, titration was performed with a standard solution of NaOH, and the ion exchange capacity was determined from the neutralization point.
(Measurement of proton conductivity)
The obtained polymer was formed into a film by a casting method, and a film having a film thickness of about 50 μm was used as a sample.

  The AC resistance was obtained by pressing a platinum wire (f = 0.5 mm) on the surface of a strip-shaped sample film having a width of 5 mm, holding the sample in a constant temperature and humidity device, and measuring AC impedance between the platinum wires. . That is, the impedance at AC 10 kHz was measured in an environment of 85 ° C. and relative humidity 90%. A chemical impedance measurement system manufactured by NF Circuit Design Block Co., Ltd. was used as the resistance measurement device, and JW241 manufactured by Yamato Scientific Co., Ltd. was used as the constant temperature and humidity device. Five platinum wires were pressed at intervals of 5 mm, the distance between the wires was changed to 5 to 20 mm, and the AC resistance was measured. The specific resistance of the membrane was calculated from the line-to-line distance and the resistance gradient, and the proton conductivity was calculated from the reciprocal of the specific resistance.

Specific resistance R (Ω · cm) = 0.5 (cm) × film thickness (cm) × resistance line gradient (Ω / cm)
(Hot water resistance)
The membrane was immersed in hot water at 120 ° C. for 24 hours, and the weight and size of the membrane immediately after taking out were compared with the membrane before immersion, and the water content and dimensional change rate were determined.
(Power generation evaluation)
The catalyst-attached electrolyte membrane is sandwiched between carbon papers and 160 ° C under a pressure of 100 kg / cm ^2.
A membrane electrode assembly (MEA) was formed by hot press molding under conditions of × 15 min. The MEA was sandwiched between two titanium current collectors, and a heater was placed outside the MEA to assemble a fuel cell having an effective area of 25 cm ² .

The temperature of the fuel cell was maintained at 85 ° C., and hydrogen and oxygen were supplied at 2 atm at a humidity of 35% RH and 100% RH. Under each condition, the voltage between terminals at current densities of 0.5 A / cm ² and 1.0 A / cm ² was measured.

Further, the temperature of the fuel cell was kept at 85 ° C., hydrogen and oxygen were supplied at 2 atm at a humidity of 35% RH, and the voltage between terminals at a current density of 0.5 A / cm ² was measured for 150 hours.
[Synthesis Example 1]
(1) Synthesis of hydrophobic unit 4, 4′-dichlorobenzophenone 60.3 g (240 mmol), 4, 4 in a 1 L separable three-necked flask equipped with a stirring blade, thermometer, nitrogen introduction tube, Dean-Stark tube, and cooling tube '-(1,4-phenylenediisopropylidene) bisphenol (Bis-P) 69.3 g (200 mmol) and potassium carbonate 35.9 g (260 mmol) were weighed. Sulfolane (370 mL) and toluene (190 mL) were added, and the mixture was heated to reflux at 150 ° C. in a nitrogen atmosphere. Water produced by the reaction is azeotroped with toluene to produce Dean-St.
Removed from arc tube. When no more water was observed after 3 hours, toluene was removed from the system and stirred at 180 ° C. for 7 hours, and then 4,4′-dichlorobenzophenone.
20.1 g (80 mmol) was added, and the mixture was further stirred for 3 hours.

After standing to cool, inorganic substances insoluble in the reaction solution were removed by filtration using Celite as a filter aid. The filtrate was then poured into 2.0 L of methanol to solidify the reaction product. The precipitated coagulum was filtered, washed with a small amount of methanol, and vacuum dried. The dried product was redissolved in 200 mL of tetrahydrofuran. This solution was poured into 2.0 L of methanol and reprecipitated. The coagulated product was filtered and dried under vacuum to obtain 103 g (yield 92%) of the desired product. The number average molecular weight in terms of polystyrene determined by GPC was 4500, and the weight average molecular weight was 6800. It was confirmed that the obtained compound was an oligomer represented by the formula (I).

[Synthesis Example 2] Synthesis of Sulfonated Polymer In a 1 L three-necked flask equipped with a stirrer, a thermometer, and a nitrogen introduction tube, 53.3 g (133 mmol) of neopentyl 3- (2,5-dichlorobenzoyl) benzenesulfonate was synthesized. 1, 74.7 g (16.6 mmol) of a hydrophobic unit having a number average molecular weight of 4,500, 2.94 g (5.0 mmol) of bis (triphenylphosphine) nickel dichloride, 0.67 g of sodium iodide (5. 0 mmol), 15.7 g (60 mmol) of triphenylphosphine, and 23.5 g (360 mmol) of zinc were weighed and substituted with dry nitrogen. 320 mL of N, N-dimethylacetamide (DMAc) was added thereto, and stirring was continued for 3 hours while maintaining the reaction temperature at 80 ° C., and then diluted by adding 540 mL of DMAc, and insoluble matter was filtered off.

The obtained solution was put into a 2 L three-necked flask equipped with a stirrer, a thermometer, and a nitrogen introduction tube. The mixture was heated and stirred at 115 ° C., and 23.2 g (266 mmol) of lithium bromide was added. After stirring for 7 hours, the product was precipitated by pouring into 3.5 L of acetone. Subsequently, after washing in order of 1N hydrochloric acid and pure water, it was dried to obtain 92 g of the desired polymer. The weight average molecular weight (Mw) of the obtained polymer was 85,000. It was confirmed that the obtained compound was a polymer represented by the formula (II).

A 10% by weight N-methyl-2-pyrrolidone (NMP) solution of the obtained sulfonated polymer was cast on a glass plate to form a film having a film thickness of 40 μm.
[Synthesis Example 3] Synthesis of hydrophobic unit 4, 4'-difluorobenzophenone 52.4 g (240 mmol), 4 L in a 1 L separable three-necked flask equipped with a stirring blade, thermometer, nitrogen introduction tube, Dean-Stark tube, and cooling tube -Chloro-4'-fluorobenzophenone 14.1 g (60.0 mmol), 4,4 '-(1,3-phenylenediisopropylidene) bisphenol (Bis-M) 70.2
g (203 mmol), 23.7 g (67.5 mmol) of bis (4-hydroxyphenyl) fluorene, and 48.5 g (351 mmol) of potassium carbonate were weighed. DMAc 430mL and toluene 220mL were added, and it heated and refluxed at 150 degreeC by nitrogen atmosphere. The water produced by the reaction was removed from the Dean-Stark tube by azeotroping with toluene. When no more water was observed after 3 hours, toluene was removed from the system and stirred at 160 ° C. for 7 hours. Then, 7.0 g (20.0 mmol) of 4-chloro-4′-fluorobenzophenone was added, The mixture was further stirred for 3 hours.

After standing to cool, inorganic substances insoluble in the reaction solution were removed by filtration using Celite as a filter aid. The filtrate was poured into 2.0 L of methanol to solidify the reaction product. The precipitated coagulum was filtered, washed with a small amount of methanol, and vacuum dried. The dried product was redissolved in 200 mL of tetrahydrofuran. This solution was poured into 2.0 L of methanol and reprecipitated. The solidified product was filtered and dried under vacuum to obtain 110 g (yield 80%) of the desired product. The number average molecular weight in terms of polystyrene determined by GPC was 6000, and the weight average molecular weight was 8,300. It was confirmed that the obtained compound was an oligomer represented by the formula (III).

As for the composition ratio of n and p, n was 0.75 and p was 0.25.
[Synthesis Example 4] Synthesis of Sulfonated Polymer In a 1 L three-necked flask equipped with a stirrer, a thermometer, and a nitrogen introduction tube, 56.1 g (140 mmol) of neopentyl 3- (2,5-dichlorobenzoyl) benzenesulfonate was synthesized. Hydrophobic unit 61.1 g (10.2 mmol) of Mn 6000 obtained in Step 3, bis (triphenylphosphine) nickel dichloride 2.94 g (5.0 mmol), sodium iodide 0.67 g (5.0 mmol), triphenyl 15.7 g (60 mmol) of phosphine and 23.5 g (360 mmol) of zinc were weighed and substituted with dry nitrogen. 290 mL of N, N-dimethylacetamide (DMAc) was added thereto, and stirring was continued for 3 hours while maintaining the reaction temperature at 80 ° C. Then, 490 mL of DMAc was added for dilution, and insoluble matters were filtered off.

  The obtained solution was put into a 2 L three-necked flask equipped with a stirrer, a thermometer, and a nitrogen introduction tube. The mixture was heated and stirred at 115 ° C., and 24.3 g (280 mmol) of lithium bromide was added. After stirring for 7 hours, the product was precipitated by pouring into 3.0 L of acetone. Subsequently, after washing in order of 1N hydrochloric acid and pure water, it was dried to obtain 97 g of the desired polymer. The weight average molecular weight (Mw) of the obtained polymer was 105,000. It was confirmed that the obtained compound was a polymer represented by the formula (IV).

A 10 wt% N-methyl-2-pyrrolidone (NMP) solution of the resulting sulfonated polymer was
The film was cast on a glass plate to obtain a film having a thickness of 40 μm.
[Synthesis Example 5] Synthesis of hydrophobic unit 48.2 g (280 mmol) of 2,6-dichlorobenzonitrile in a 1 L separable three-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, a Dean-Stark tube, and a cooling tube
1,3-bis (4-hydroxyphenoxy) benzene 38.3 g (130 mmol), 9
, 9-bis (4-hydroxyphenyl) fluorene (45.6 g, 130 mmol) and potassium carbonate (46.7 g, 338 mmol) were weighed. Sulfolane (370 mL) and toluene (190 mL) were added, and the mixture was heated to reflux at 150 ° C. in a nitrogen atmosphere. The water produced by the reaction was removed from the Dean-Stark tube by azeotroping with toluene. When no more water was observed after 3 hours, toluene was removed from the system and stirred at 180 ° C. for 7 hours. Then, 6.88 g (40 mmol) of 2,6-dichlorobenzonitrile was added, and the mixture was further stirred for 3 hours. .

After standing to cool, inorganic substances insoluble in the reaction solution were removed by filtration using Celite as a filter aid. The filtrate was poured into 2.0 L of methanol to solidify the reaction product. The precipitated coagulum was filtered, washed with a small amount of methanol, and vacuum dried. The dried product was redissolved in 200 mL of tetrahydrofuran. This solution was poured into 2.0 L of methanol and reprecipitated. The coagulated product was filtered and dried under vacuum to obtain 106 g (yield 91%) of the desired product. The number average molecular weight in terms of polystyrene determined by GPC was 8,100, and the weight average molecular weight was 9,500. It was confirmed that the obtained compound was an oligomer represented by the formula (V).

As for the composition ratio of n and p, n was 0.50 and p was 0.50.
[Synthesis Example 6] Synthesis of Sulfonated Polymer In a 1 L three-necked flask equipped with a stirrer, a thermometer, and a nitrogen introduction tube, 56.8 g (141 mmol) of neopentyl 3- (2,5-dichlorobenzoyl) benzenesulfonate was synthesized. Hydrophobic unit 69.5 g (8.6 mmol) of Mn8100 obtained in No. 5, 2.94 g (5.0 mmol) of bis (triphenylphosphine) nickel dichloride, 0.67 g (5.0 mmol) of sodium iodide, triphenyl 15.7 g (60 mmol) of phosphine and 23.5 g (360 mmol) of zinc were weighed and substituted with dry nitrogen. N, N-dimethylacetamide (DMAc) (320 mL) was added thereto, and stirring was continued for 3 hours while maintaining the reaction temperature at 80 ° C., and then DMAc (530 mL) was added for dilution, and insoluble matters were filtered.

The obtained solution was put into a 2 L three-necked flask equipped with a stirrer, a thermometer, and a nitrogen introduction tube. The mixture was heated and stirred at 115 ° C., and 24.6 g (282 mmol) of lithium bromide was added. After stirring for 7 hours, the product was precipitated by pouring into 3.4 L of acetone. Subsequently, it was washed with 1N hydrochloric acid and pure water in this order and dried to obtain 103 g of the desired polymer. The weight average molecular weight (Mw) of the obtained polymer was 97,000. It was confirmed that the obtained compound was a polymer represented by the formula (VI).

A 10% by weight N-methyl-2-pyrrolidone (NMP) solution of the obtained sulfonated polymer was cast on a glass plate to form a film having a film thickness of 40 μm.
Synthesis Example 7 Synthesis of Hydrophobic Unit 4, 4′-Dichlorobenzophenone 45.2 g (180 mmol), 4 L in a 1 L separable three-necked flask equipped with a stirring blade, thermometer, nitrogen introduction tube, Dean-Stark tube, and condenser tube , 4 ′-(1,4-phenylenediisopropylidene) bisphenol (Bis-P) 33.3 g (96.0 mmol), 4,4′-biphenol 11.9 g (64.0 mmol)
Then, 28.7 g (208 mmol) of potassium carbonate was weighed. 270 mL of sulfolane and 135 mL of toluene were added, and the mixture was heated to reflux at 150 ° C. in a nitrogen atmosphere. The water produced by the reaction was removed from the Dean-Stark tube by azeotroping with toluene. When no more water was observed after 3 hours, toluene was removed from the system and stirred at 180 ° C. for 7 hours. Then, 15.1 g (60 mmol) of 4,4′-dichlorobenzophenone was added, and the mixture was further stirred for 3 hours. .

After standing to cool, inorganic substances insoluble in the reaction solution were removed by filtration using Celite as a filter aid. The filtrate was poured into 2.0 L of methanol to solidify the reaction product. The precipitated coagulum was filtered, washed with a small amount of methanol, and vacuum dried. The dried product was redissolved in 150 mL of tetrahydrofuran. This solution was poured into 2.0 L of methanol and reprecipitated. The coagulated product was filtered and vacuum-dried to obtain 65 g (yield 85%) of the desired product. The number average molecular weight in terms of polystyrene determined by GPC was 6400, and the weight average molecular weight was 7800. It was confirmed that the obtained compound was an oligomer represented by the formula (VII).

As for the composition ratio of n and p, n was 0.60 and p was 0.40.
[Synthesis Example 8] Synthesis of Sulfonated Polymer In a 1 L three-necked flask equipped with a stirrer, a thermometer, and a nitrogen introduction tube, 56.8 g (141 mmol) of neopentyl 3- (2,5-dichlorobenzoyl) benzenesulfonate was synthesized. Hydrophobic unit 55.0 g (8.6 mmol) of Mn6400 obtained in No. 7, 2.94 g (5.0 mmol) of bis (triphenylphosphine) nickel dichloride, 0.67 g (5.0 mmol) of sodium iodide, triphenyl 15.7 g (60 mmol) of phosphine and 23.5 g (360 mmol) of zinc were weighed and substituted with dry nitrogen. 280 mL of N, N-dimethylacetamide (DMAc) was added thereto, and stirring was continued for 3 hours while maintaining the reaction temperature at 80 ° C. Then, 460 mL of DMAc was added for dilution, and insoluble matters were filtered off.

  The obtained solution was put into a 2 L three-necked flask equipped with a stirrer, a thermometer, and a nitrogen introduction tube. The mixture was heated and stirred at 115 ° C., and 24.6 g (285 mmol) of lithium bromide was added. After stirring for 7 hours, the product was precipitated by pouring into 5.0 L of acetone. Subsequently, it was washed with 1N hydrochloric acid and pure water in this order, and then dried to obtain 82 g of the desired polymer. The weight average molecular weight (Mw) of the obtained polymer was 93,000. It was confirmed that the obtained compound was a polymer represented by the formula (VIII).

A 10% by weight N-methyl-2-pyrrolidone (NMP) solution of the obtained sulfonated polymer was cast on a glass plate to form a film having a film thickness of 40 μm.
[Synthesis Example 9] (equivalent to Comparative Example)
To a 1 L separable three-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, a Dean-Stark tube, and a cooling tube, 4,4′-dichlorobenzophenone 50.2 g (200 mmol), 9,9-bis (4-hydroxyphenyl) ) Weighed 11.1 g (55.0 mmol) of fluorene, 57.8 g (165 mmol) of 4,4′-dihydroxydiphenyl ether, and 39.5 g (286 mmol) of potassium carbonate. Sulfolane (340 mL) and toluene (170 mL) were added, and the mixture was heated to reflux at 150 ° C. in a nitrogen atmosphere. The water produced by the reaction was removed from the Dean-Stark tube by azeotroping with toluene. When no more water was observed after 3 hours, toluene was removed from the system and stirred at 180 ° C. for 7 hours. Then, 10.0 g (40.0 mmol) of 4,4′-dichlorobenzophenone was added, and another 3 hours Stir.

After standing to cool, inorganic substances insoluble in the reaction solution were removed by filtration using Celite as a filter aid. The filtrate was poured into 2.0 L of methanol to solidify the reaction product. The precipitated coagulum was filtered, washed with a small amount of methanol, and vacuum dried. The dried product is added to 150 ml of tetrahydrofuran.
Redissolved in L. This solution was poured into 1.5 L of methanol and reprecipitated. Filter the coagulum,
Vacuum drying gave 87 g (yield 83%) of the desired product. The number average molecular weight in terms of polystyrene determined by GPC was 5,500, and the weight average molecular weight was 8,500. It was confirmed that the obtained compound was an oligomer represented by the formula (IX).

[Synthesis Example 10] (Comparative Example) Synthesis of Sulfonated Polymer Into a 1 L three-necked flask equipped with a stirrer, a thermometer, and a nitrogen introduction tube, 55.2 g (138 mmol) of neopentyl 3- (2,5-dichlorobenzoyl) benzenesulfonate. ), 67.9 g (12.3 mmol) of hydrophobic unit of Mn5500 obtained in Synthesis Example 9, 2.94 g (5.0 mmol) of bis (triphenylphosphine) nickel dichloride, 0.67 g (5.0 mmol) of sodium iodide. ), 15.7 g (60 mmol) of triphenylphosphine and 23.5 g (360 mmol) of zinc were weighed and purged with dry nitrogen. N, N-dimethylacetamide (DMAc) (300 mL) was added thereto, and stirring was continued for 3 hours while maintaining the reaction temperature at 80 ° C. Then, DMAc (520 mL) was added to dilute, and insoluble matters were filtered.

The obtained solution was put into a 2 L three-necked flask equipped with a stirrer, a thermometer, and a nitrogen introduction tube. The mixture was heated and stirred at 115 ° C., and 23.9 g (275 mmol) of lithium bromide was added. After stirring for 7 hours, the product was precipitated by pouring into 3.2 L of acetone. Subsequently, it was washed with 1N hydrochloric acid and pure water in this order, and then dried to obtain 88 g of the desired polymer. The weight average molecular weight (Mw) of the obtained polymer was 93,000. It was confirmed that the obtained compound was a polymer represented by the formula (X).

A 10% by weight N-methyl-2-pyrrolidone (NMP) solution of the obtained sulfonated polymer was cast on a glass plate to form a film having a film thickness of 40 μm.
[Evaluation]
The physical properties of the sulfonated polymers and films (proton conducting membranes) synthesized in Synthesis Examples 2 and 4, 6, 8, and Synthesis Example 10 were evaluated. The results are shown in Table 1.

[Example 1]
[Preparation of paste A]
Put 50 g of zirconia balls (trade name: YTZ ball, manufactured by Nikkato Co., Ltd.) 25 g in a 50 ml glass bottle, and carry platinum-supported carbon particles (Pt: 46 wt%, (Tanaka Kikinzoku Kogyo Co., Ltd .: TEC10E50E) 1.51 g. 0.88 g of distilled water, 3.23 g of 15% water-1, dimethoxyethane solution (weight ratio 10:90) of the polymer of Synthesis Example 2, 13.97 g of 1,2-dimethoxyethane, vapor grown carbon fiber (Product name: VGCF, manufactured by Showa Denko Co., Ltd.) 0.1 g and a dispersant (trade name: DA234, manufactured by Enomoto Kasei Co., Ltd.) 0.028 g were added, and the mixture was stirred for 60 minutes with a wave blower. Paste A was obtained.

[Create electrode]
On the PET film treated with a release agent, paste A was applied using a doctor blade so that the platinum coating amount was 0.5 mg / cm ² . This was heated and dried at 95 ° C. for 10 minutes to form an electrode layer.

[Creating electrolyte membrane with catalyst]
One electrolyte membrane having a film thickness of 50 μm made of a polymer having a weight average molecular weight (Mw) of 170,000 having a structure represented by the following general formula (XI) is prepared, sandwiched between two electrode layers, and a pressure of 100 kg / cm. ² and hot press molding under the conditions of 160 ° C. × 15 min to prepare an electrolyte membrane with a catalyst.

[Example 2]
[Preparation of paste B]
Put 50 g of zirconia balls (trade name: YTZ ball, manufactured by Nikkato Co., Ltd.) 25 g in a 50 ml glass bottle, and carry platinum-supported carbon particles (Pt: 46 wt%, (Tanaka Kikinzoku Kogyo Co., Ltd .: TEC10E50E) 1.51 g. 0.88 g of distilled water, 3.23 g of 15% water-1,2 dimethoxyethane solution (weight ratio 10:90) of the polymer of Synthesis Example 4, 13.97 g of 1,2-dimethoxyethane, vapor grown carbon fiber (Product name: VGCF, manufactured by Showa Denko Co., Ltd.) 0.1 g and a dispersant (trade name: DA234, manufactured by Enomoto Kasei Co., Ltd.) 0.028 g were added, and the mixture was stirred for 60 minutes with a wave blower. Paste B was obtained.

[Create electrode]
On the PET film treated with a release agent, paste B was applied using a doctor blade so that the platinum coating amount was 0.5 mg / cm ² . This was heated and dried at 95 ° C. for 10 minutes to form an electrode layer.

[Creating electrolyte membrane with catalyst]
One electrolyte membrane having a thickness of 50 μm made of a polymer having a weight average molecular weight (Mw) of 170,000 having a structure represented by the above general formula (XI) is prepared, and sandwiched between two electrode layers, and a pressure of 100 kg / cm ² and hot press molding under the conditions of 160 ° C. × 15 min to prepare an electrolyte membrane with a catalyst.
[Example 3]
[Preparation of paste C]
Put 50 g of zirconia balls (trade name: YTZ ball, manufactured by Nikkato Co., Ltd.) 25 g in a 50 ml glass bottle, and carry platinum-supported carbon particles (Pt: 46 wt%, (Tanaka Kikinzoku Kogyo Co., Ltd .: TEC10E50E) 1.51 g. 0.88 g of distilled water, 3.23 g of 15% water-1, dimethoxyethane solution of the polymer of Synthesis Example 6 (weight ratio 10:90), 13.97 g of 1,2-dimethoxyethane, vapor grown carbon fiber (Product name: VGCF, manufactured by Showa Denko Co., Ltd.) 0.1 g and a dispersant (trade name: DA234, manufactured by Enomoto Kasei Co., Ltd.) 0.028 g were added, and the mixture was stirred for 60 minutes with a wave blower, and the viscosity was 50 cp (25 ° C.). Paste C was obtained.

[Create electrode]
Paste C was applied onto a PET film treated with a release agent using a doctor blade so that the platinum coating amount was 0.5 mg / cm ² . This was heated and dried at 95 ° C. for 10 minutes to form an electrode layer.

[Creating electrolyte membrane with catalyst]
One electrolyte membrane having a thickness of 50 μm made of a polymer having a weight average molecular weight (Mw) of 170,000 having a structure represented by the above general formula (XI) is prepared, and sandwiched between two electrode layers, and a pressure of 100 kg / cm. ² and hot press molding under the conditions of 160 ° C. × 15 min to prepare an electrolyte membrane with a catalyst.
[Example 4]
[Preparation of paste D]
Put 50 g of zirconia balls (trade name: YTZ ball, manufactured by Nikkato Co., Ltd.) 25 g in a 50 ml glass bottle, and carry platinum-supported carbon particles (Pt: 46 wt%, (Tanaka Kikinzoku Kogyo Co., Ltd .: TEC10E50E) 1.51 g. 0.88 g of distilled water, 3.23 g of 15% water-1,2 dimethoxyethane solution of the polymer of Synthesis Example 8 (weight ratio 10:90), 13.97 g of 1,2-dimethoxyethane, vapor grown carbon fiber (Product name: VGCF, manufactured by Showa Denko Co., Ltd.) 0.1 g and a dispersant (trade name: DA234, manufactured by Enomoto Kasei Co., Ltd.) 0.028 g were added, and the mixture was stirred for 60 minutes with a wave blower. Paste D was obtained.

[Create electrode]
On the PET film treated with a release agent, paste D was applied using a doctor blade so that the platinum coating amount was 0.5 mg / cm ² . This was heated and dried at 95 ° C. for 10 minutes to form an electrode layer.

[Creating electrolyte membrane with catalyst]
One electrolyte membrane having a thickness of 50 μm made of a polymer having a weight average molecular weight (Mw) of 170,000 having a structure represented by the above general formula (XI) is prepared, and sandwiched between two electrode layers, and a pressure of 100 kg / cm. ² and hot press molding under the conditions of 160 ° C. × 15 min to prepare an electrolyte membrane with a catalyst.
[Comparative example]
[Preparation of paste E]
Put 50 g of zirconia balls (trade name: YTZ ball, manufactured by Nikkato Co., Ltd.) 25 g in a 50 ml glass bottle, and carry platinum-supported carbon particles (Pt: 46 wt%, (Tanaka Kikinzoku Kogyo Co., Ltd .: TEC10E50E) 1.51 g. 0.88 g of distilled water, 3.23 g of 15% water-1,2 dimethoxyethane solution of the polymer of Synthesis Example 10 (weight ratio 10:90), 13.97 g of 1,2-dimethoxyethane, vapor grown carbon fiber (Product name: VGCF, manufactured by Showa Denko Co., Ltd.) 0.1 g and a dispersant (trade name: DA234, manufactured by Enomoto Kasei Co., Ltd.) 0.028 g were added, and the mixture was stirred for 60 minutes with a wave blower. Paste E was obtained.

[Create electrode]
Paste E was applied onto a PET film treated with a release agent using a doctor blade so that the platinum coating amount was 0.5 mg / cm ² . This was heated and dried at 95 ° C. for 10 minutes to form an electrode layer.

[Creating electrolyte membrane with catalyst]
One electrolyte membrane having a thickness of 50 μm made of a polymer having a weight average molecular weight (Mw) of 170,000 having a structure represented by the above general formula (XI) is prepared, and sandwiched between two electrode layers, and a pressure of 100 kg / cm. ² and hot press molding under the conditions of 160 ° C. × 15 min to prepare an electrolyte membrane with a catalyst.
[Evaluation]
Next, Table 2 shows the evaluation results of the power generation characteristics. The electrode-attached electrolyte membrane prepared from the electrolyte of the present invention is excellent in the adhesion between the electrode and the membrane, so that a high terminal voltage can be obtained at each current density even in measurement under conditions of high temperature and high humidity. It can be seen that the power generation performance is excellent.

Claims (8)

A polymer electrolyte fuel cell electrode electrolyte comprising a polyarylene copolymer containing a structural unit represented by the general formula (1) and a structural unit that provides proton conductivity.

, - - a direct bond, -O is wherein (1), A, D, E S -, - CO -, - SO 2 -, - SO -, - CONH -, - COO -, - (CF 2) _f - (f is an integer of 1 to _{10), - (CH 2) h} - (h is an integer of 1 to _{10), - CR '2 - (} R' is an aliphatic hydrocarbon group, an aromatic A hydrocarbon group and a halogenated hydrocarbon group), at least one structure selected from the group consisting of a cyclohexylidene group and a fluorenylidene group.
B is shows the oxygen atom or a sulfur atom independently.
R _{1 to} R _{28 each} represent a hydrogen atom or a nitrile group.
l and o represent an integer of 0 to 4, m represents an integer of 1 to 4, and q represents an integer of 2 or more. n and p indicate the composition ratio of each unit and take a value of 0 to 1, where n + p = 1. However, n takes a value other than 0. ] 2. The polymer electrolyte fuel cell electrode electrolyte according to claim 1, wherein the structural unit represented by the formula (1) is a structural unit represented by the following general formula (2).

[In the formula (2), A and E are a direct bond, —O—, —CO—, —SO ₂ —, —SO—, — (CF ₂ ) _f — (f is an integer of 1 to 10), — (CH ₂ ) _h — (h is an integer of 1 to 10), —CR ′ ₂ — (R ′ represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group and a halogenated hydrocarbon group), cyclohexyl It shows at least one structure selected from the group consisting of a silidene group and a fluorenylidene group.
D is a direct bond, —O—, —CO—, — (CH ₂ ) _h — (h is an integer of 1 to 10), —CR ″ ₂ — (R ″ is an aliphatic hydrocarbon group, aromatic It shows the family hydrocarbon group). R _{1 to} R ₂₈ may be the same as or different from each other, and are selected from a hydrogen atom, a fluorine atom, an alkyl group, a halogenated alkyl group, an allyl group, an aryl group, a nitro group, and a nitrile group, which are partially or completely halogenated. At least one atom or group selected from the group consisting of: L and o each represent an integer of 0 to 4, and q represents an integer of 2 or more. n and p indicate the composition ratio of each unit and take a value of 0 to 1, where n + p = 1. However, n takes a value other than 0. ] 3. The polymer electrolyte fuel cell electrode electrolyte according to claim 2, which is a structural unit represented by the following general formula (3).

[In the formula (3), D represents —O— or —CR ″ ₂ — (R ″ represents an aliphatic hydrocarbon group or an aromatic hydrocarbon group). P is at least one structure selected from structures represented by the following general formulas (4-1) to (4-3), and Q is represented by the following general formulas (5-1) to (5-12). At least one structure selected from the following structures. Q represents an integer of 2 or more. n and p indicate the composition ratio of each unit and take a value of 0 to 1, where n + p = 1. However, n takes a value other than 0. ]

  4. The polymer electrolyte fuel cell electrode electrolyte according to claim 3, wherein in the general formula (3), n = 0.3 to 1. The polymer electrolyte fuel cell electrode electrolyte according to any one of claims 1 to 4, wherein the polyarylene copolymer further contains a structural unit represented by the following general formula (6).

Wherein Y is —CO—, —SO ₂ —, —SO—, —CONH—, —COO—, — (CF ₂ ) _f — (l is an integer of 1 to 10), —C (CF _{3) 2} - represents at least one structure selected from the group consisting of, Z is a direct bond _{or, - (CH 2) h -} (h is an integer of 1 to 10), - C (CH _{3) 2} represents at least one structure selected from the group consisting of —, —O—, and —S—, and Ar represents —SO ₃ H or —O (CH ₂ ) _r SO ₃ H or —O (CF ₂ ) _r. An aromatic group having a substituent represented by SO ₃ H. r represents an integer of 1 to 12, j represents an integer of 0 to 10, k represents an integer of 0 to 10, and i represents 1 Represents an integer of ~ 4.)   An electrode paste comprising the electrolyte according to claim 1, catalyst particles, and a solvent.   An electrode for a polymer electrolyte fuel cell comprising the electrolyte according to any one of claims 1 to 5 and catalyst particles.   A membrane-electrode assembly comprising the electrode according to claim 7 on at least one surface of a polymer electrolyte membrane.