JP2010009912A - Electrode electrolyte for solid polymer fuel cell, and electrode varnish, electrode paste and membrane electrode assembly using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrode electrolyte excellent in heat resistance and mechanical characteristics for a solid polymer fuel cell. <P>SOLUTION: The electrode electrolyte for a fuel cell contains a polyarylene copolymer containing a condensed aromatic ring unit represented by formula (1) and a unit having a polyphenylene structure for its main chain and having in its side chain a nitrogen-containing heterocyclic ring represented by the below formula (A). In the formula (1): A and D are direct bonds, -O-, -S-, -CO- or the like; Ph is a condensed aromatic ring; R<SB>1</SB>-R<SB>20</SB>are each a hydrogen atom, a fluorine atom, a hydrocarbon group, an alkyl halide group, a nitro group, a nitryl group and the like; (l) and (m) are each an integer of 0-4, (q) an integer of 2 or more, and (t) an integer of 0-4; (n) and (p) are each a composition ratio of the respective unit; and (n)+(p)=1. In the formula (A), Z is a direct bond, -O-, -S- or the like; Y is -CO-, -SO<SB>2</SB>-, -SO-, -CONH- or the like; R<SB>21</SB>is a nitrogen-containing heterocyclic group; (b) is an integer of 1-5; and (a) is an integer of 0-4. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electrode electrolyte for a polymer electrolyte fuel cell containing polyarylene having a specific structural unit, an electrode varnish containing the electrolyte, an electrode paste, an electrode for a polymer electrolyte fuel cell formed from the electrode paste, and The present invention relates to a membrane-electrode assembly having the electrode.

  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, and 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.

  In such fuel cells, conventionally, perfluoroalkylsulfonic acid polymers represented by Nafion (trademark) have been used as the electrolyte of the electrode catalyst layer as well as the proton conducting membrane. 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 that a sulfonated polyarylene polymer is used as an electrode electrolyte, and further, Japanese Patent Application Laid-Open No. 2004-253267 (Patent Document 2), JP 2006-121051 (Patent Document 3) discloses the use of a specific sulfonated polyarylene.
Japanese Patent Laying-Open No. 2005-50726 JP 2004-253267 A JP 2006-121051 A

  These polyarylene-based (aromatic sulfonic acid-based) electrolyte materials solve the above-mentioned cost problems and problems related to the recovery of catalytic metals, as well as high heat resistance, solvent resistance, Electrode for polymer electrolyte fuel cell, which is superior in use in high temperature and humidity range, excellent proton conductivity, dimensional stability and mechanical properties compared to Nafion because it can be given hydrothermal resistance An electrolyte can be provided.

  It has been desired that the fuel cell itself has a higher power generation output, particularly at high temperatures. In such a fuel cell, hydrogen peroxide is generated by oxidation of the fuel in the cell during power generation, thereby generating active species such as hydroxy radicals, which may cause degradation of the electrode electrolyte and cause performance degradation. Are known. Therefore, improvement in durability against chemical deterioration of the electrode electrolyte has also been demanded.

  In addition, in an electrode electrolyte made of a polymer having a sulfonic acid group used in such a fuel cell, a reversible elimination reaction of the sulfonic acid group and a crosslinking reaction involving the sulfonic acid occur at a high temperature. was there. As a result, there is a problem that the proton conductivity is reduced or the electrode electrolyte is embrittled, resulting in a decrease in the power generation output of the fuel cell and the inability to generate power. 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.

That is, the problem of the present invention is to solve the above-mentioned problem of cost and the problem of recovery of the catalytic metal, and is excellent in proton conductivity, dimensional stability and mechanical properties, and also excellent at high temperature. It has hot water resistance and heat resistance, high power output, and MEA
The present invention provides an electrode electrolyte for a polymer electrolyte fuel cell imparted with processing suitability at the time of production, and further provides an electrode varnish, an electrode paste, an electrode, and a membrane-electrode assembly containing the electrolyte.

The present inventors have intensively studied to solve the above problems. As a result, it has been found that the above problem can be solved by introducing a unit having a nitrogen-containing heterocyclic group into polyarylene having a condensed aromatic ring unit, and the present invention has been completed.
[1] A condensed aromatic ring unit represented by the formula (1):
A solid polymer fuel cell comprising a polyarylene copolymer having a main chain having a polyphenylene structure and a side chain having a nitrogen-containing heterocyclic group represented by the following formula (A): Electrode electrolyte for use.

Wherein (1), A, D is a direct bond, -O -, - S -, - CO -, - SO 2 -, - SO -, - CONH -, - COO -, - (CF 2) i - (I is an integer of 1 to 10), — (CH ₂ ) _j — (j is an integer of 1 to 10), —CR ′ ₂ — (R ′ is an aliphatic hydrocarbon group, 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, B represents an oxygen atom or a sulfur atom, and Ph represents a condensed aromatic ring. shown, R ₁ to R ₂₀ may be the being the same or different, a hydrogen atom, a fluorine atom, an alkyl group, a part or all of halogenated halogenated alkyl group, an allyl group, an aryl group, At least one atom selected from the group consisting of a nitro group and a nitrile group The other represents a group. l and m represent an integer of 0 to 4, and q represents an integer of 2 or more. t shows the integer of 0-4. n and p indicate the composition ratio of each unit, and p is a value other than 0 among 0 to 1, and n + p = 1.

In the formula (A), Z is a direct bond or at least one selected from the group consisting of —O— and —S—.
Indicates the type of structure, Y _{is, -CO -, - SO 2 -} , - SO -, - CONH -, - COO-,
_{- (CF 2) l '-} (l' is an integer of 1 to _{10), - C (CF 3)} 2 - represents at least one structure selected from the group consisting of, R ₂₁ is a nitrogen-containing heterocyclic A ring group is shown. b shows the integer of 1-5, a shows the integer of 0-4.

Among the single lines at the end of the structural unit, those not having a substituent displayed on one side mean connection with the adjacent structural unit. ]
[2] In the above formula (1), Ph is a divalent group consisting of an aromatic ring selected from the group consisting of naphthalene, anthracene, tetracene and pentacene, [1] Fuel cell electrode electrolyte.
[3] The polymer electrolyte fuel cell electrode electrolyte according to [1], wherein the condensed aromatic ring unit is represented by the following formula (2):

[In the formula (2), A represents a direct bond, —O—, —CO—, —SO ₂ —, —SO—, — (CF ₂ ) _i.
- (i is an integer of 1 to _{10), - (CH 2) j} - (j is an integer of 1 to _{10), - CR '2 - (} R' represents an aliphatic hydrocarbon group, an aromatic hydrocarbon A hydrogen group or 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 ) _j — (j is an integer of 1 to 10) and —CR ′ ₂ — (R ′ is an aliphatic hydrocarbon group, aromatic carbonization. Represents at least one structure selected from the group consisting of a hydrogen group or a halogenated hydrocarbon group),
Ph represents a condensed aromatic ring, R _{1 to} R ₂₀ may be the same 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, At least one atom or group selected from the group consisting of allyl group, aryl group, nitro group and nitrile group is shown.

l represents an integer of 0 to 4, and q represents an integer of 2 or more. t shows the integer of 0-4.
n and p indicate the composition ratio of each unit, and p is a value other than 0 among 0 to 1, and n + p = 1.

Among the single lines at the end of the structural unit, those not having a substituent displayed on one side mean connection with the adjacent structural unit. ]
[4] The polymer electrolyte fuel cell electrode electrolyte according to [3], wherein the condensed aromatic ring unit is represented by the formula (3);

[In the formula (3), D is selected from the group consisting of —O—, —CR ′ ₂ — (R ′ represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group or a halogenated hydrocarbon group). At least one structure is shown.

P is at least one structure selected from structures represented by the following formulas (4-1) to (4-3);
Ph is a structure represented by the following formula (5-1).

q represents an integer of 2 or more. t shows the integer of 0-4.
n and p indicate the composition ratio of each unit, and p is a value other than 0 among 0 to 1, and n + p = 1.

  Among the single lines at the end of the structural unit, those not having a substituent displayed on one side mean connection with the adjacent structural unit. ]

[5] The electrode electrolyte for a polymer electrolyte fuel cell according to [4], wherein in the formula (3), p is in the range of 0.01 to 1.
[6] The nitrogen-containing heterocyclic group is pyrrole, thiazole, isothiazole, oxazole, isoxazole, pyridine, imidazole, imidazoline, pyrazole, 1,3,5-triazine, pyrimidine, pyritazine, pyrazine, indole, quinoline, isoquinoline, At least one compound derived from a nitrogen-containing heterocyclic compound consisting of bryne, benzimidazole, benzoxazole, benzthiazole, tetrazole, tetrazine, triazole, carbazole, acridine, quinoxaline, quinazoline and a compound selected from the group consisting of these derivatives [1] to [5], which are basic polymer electrolyte fuel cell electrode electrolytes.
[7] The electrode electrolyte for a polymer electrolyte fuel cell according to [1], wherein the unit having a nitrogen-containing heterocyclic group in the side chain is a structural unit represented by the following general formula (B).

(In the formula (B), Y, Z, R ₂₁ , a, and b are the same as those in the formula (A). Of the single wires at the end of the structural unit, those not having a substituent on one side are adjacent to each other. (8) The polyarylene-based copolymer further includes a side chain having a sulfonic acid group represented by the following general formula (E) [1] ] Electrode electrolyte for polymer electrolyte fuel cell of [7]-[7].

(In the formula (E), Z is a direct bond or at least one selected from the group consisting of -O- and -S-.
Indicates the type of structure, Y _{is, -CO -, - SO 2 -} , - SO -, - CONH -, - COO-,
_{- (CF 2) l '-} (l' is an integer of 1 to 10), - indicating at least one structure selected from the group consisting of - C (CF _{3) 2.} Ar is an aromatic group having a substituent represented by —SO ₃ H, —O (CH ₂ ) _h SO ₃ H or —O (CF ₂ ) _h SO ₃ H (h represents an integer of 1 to 12). Indicates. c
Represents an integer of 0 to 10, d represents an integer of 0 to 10, and k represents an integer of 1 to 4. )
[9] The polyarylene copolymer according to [8], wherein the side chain having a sulfonic acid group is a structural unit represented by the following general formula (F).

(In the formula (F), Y, Z, Ar, c, d, and k are the same as those in the formula (E). Of the single lines at the end of the structural unit, those that do not have a substituent on one side are adjacent. (It means connection with a matching unit.)
[10] An electrode varnish comprising the polymer electrolyte fuel cell electrode electrolyte of [1] to [9].
[11] An electrode paste comprising the polymer electrolyte fuel cell electrode electrolyte of [1] to [9] and catalyst particles.
[12] The electrode paste according to [11], wherein the solvent constituting the paste is a mixed solvent of water and at least one organic solvent, and the mixed solvent is a poor solvent for the proton conductive membrane. [13] A polymer electrolyte fuel cell electrode comprising the polymer electrolyte fuel cell electrode electrolyte of [1] to [9] and catalyst particles.
[14] A membrane-electrode assembly comprising the polymer electrolyte fuel cell electrode according to [13] on at least one surface of a polymer electrolyte membrane.

According to the present invention, it is inexpensive and easy to recover catalytic metal, and proton conductivity, dimensional stability, mechanical properties, mechanical properties, and workability (bonding of proton conducting membrane / gas diffusion layer and electrode layer) ), Improved durability against chemical degradation, and includes a sulfonated polymer having a condensed aromatic ring unit and a unit having a nitrogen-containing heterocyclic group. Electrode for a polymer electrolyte fuel cell, which is less swelled with an electrode electrolyte, has improved sulfonic acid group stability under high temperature conditions, and has excellent power generation performance and power generation durability, including the electrolyte An electrode varnish, an electrode paste, an electrode for a polymer electrolyte fuel cell, and a membrane-electrode assembly are provided, which contributes to an improvement in power generation performance of the polymer electrolyte fuel cell.

Hereinafter, the electrode electrolyte, electrode varnish, electrode paste, electrode and membrane-electrode assembly (MEA) according to the present invention will be described in detail.
[Electrode electrolyte for polymer electrolyte fuel cells]
The electrode electrolyte for a polymer electrolyte fuel cell of the present invention has a polyarylene copolymer having a sulfonic acid group (hereinafter referred to as a sulfonated polyarylene), a condensed aromatic ring unit, and a nitrogen-containing heterocyclic group. It is characterized by containing polyarylene containing a structure.

The electrode electrolyte of the present invention may include such a sulfonated polyarylene alone, or may include a conventionally known electrode electrolyte.
Since the sulfonated polyarylene having such a structure includes a unit containing a condensed aromatic ring, it has high hot water resistance and suppresses swelling of the electrode electrolyte in the immersed state. Moreover, since the nitrogen atom of a nitrogen-containing heterocyclic group has basicity, it forms an ionic interaction with a sulfonic acid group. This enhances the stability of the sulfonic acid group and suppresses the elimination of the sulfonic acid group under high temperature conditions. Similarly, the cross-linking reaction between polymer molecules derived from sulfonic acid groups can be suppressed under high temperature conditions. The nitrogen-containing heterocyclic group is a basic group having an appropriate strength that can exhibit these effects without impairing proton conductivity.

For this reason, the electrode electrolyte containing the sulfonated polyarylene can generate power even in a wide range of temperatures and humidity, particularly at high temperatures, and can improve the power generation output. In addition, even when used at high temperatures, the sulfonic acid group has high stability, so that a fuel cell with greatly improved battery life can be obtained.
Sulfonated polyarylene The sulfonated polyarylene used in the present invention includes a condensed aromatic ring unit and a unit having a nitrogen-containing heterocyclic group.
[Condensed aromatic ring unit]
The condensed aromatic ring unit is a monomer unit (constituent unit) represented by the following formula (1). By including such a unit, a hydrophobic portion can be imparted to the polymer. Moreover, since it has a condensed aromatic ring, the hot water resistance of the polymer can be improved.

In formula (1), l and m 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 p is a value other than 0 among 0 to 1, and n + p = 1. Of these, m is preferably 0 or 1, and l is preferably 0 or 1. Further, p preferably takes a value of 0.01 to 1, more preferably 0.1 to 1, and particularly preferably 0.05 to 1. t represents an integer of 0 to 4, preferably 0 to 2, more preferably 0 or 1.

A is a direct bond, -O -, - S -, - CO -, - SO 2 -, - SO -, - CONH -, -
COO—, — (CF ₂ ) _i — (i is an integer of 1 to 10), — (CH ₂ ) _j — (j is an integer of 1 to 10), —CR ′ ₂ — (R ′ is It represents at least one structure selected from the group consisting of an aliphatic hydrocarbon group, an aromatic hydrocarbon group or a halogenated hydrocarbon group), a cyclohexylidene group and a fluorenylidene group.

Here, as specific examples of R ′ of —CR ′ ₂ —, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, t-butyl group, propyl group, octyl group, decyl group, An octadecyl group, a phenyl group, a trifluoromethyl group, etc. are mentioned. Of these, a direct bond, —O—, and —CR ′ ₂ — (R ′ represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a halogenated hydrocarbon group) are preferable.

B represents an oxygen atom or a sulfur atom, preferably an oxygen atom.
Ph represents a divalent group composed of an aromatic ring, and examples thereof include a divalent group composed of an aromatic ring such as naphthalene, anthracene, tetracene, and pentacene. Among them, a divalent group composed of a naphthalene ring is preferable. By containing these, water resistance can be imparted to the sulfonated polyarylene containing the condensed aromatic ring unit represented by the formula (1).

D is a direct bond, —O—, —S—, —CO—, —SO ₂ —, —SO—, —CONH—,
—COO—, — (CF ₂ ) _i — (i is an integer of 1 to 10), — (CH ₂ ) _j — (j is an integer of 1 to 10), —CR ′ ₂ — (R ′ Represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group or a halogenated hydrocarbon group), and represents at least one structure selected from the group consisting of a cyclohexylidene group and a fluorenylidene group.

Of the single wires at the end of each structural unit, one not having a substituent displayed on one side means connection with an adjacent structural unit.
Here, as specific examples of R ′ in —CR ′ ₂ —, a methyl group, an ethyl group, a propyl group,
Examples include isopropyl group, butyl group, isobutyl group, t-butyl group, propyl group, octyl group, decyl group, octadecyl group, phenyl group and trifluoromethyl group. Among these, a direct _{bond, -O -, - CR '2} - (R' represents an aliphatic hydrocarbon group, aromatic hydrocarbon group or a halogenated hydrocarbon group).

  It is preferable that the condensed aromatic ring unit is represented by the formula (2).

[In the formula (2), A represents a direct bond, —O—, —CO—, —SO ₂ —, —SO—, — (CF ₂ ) _i.
- (i is an integer of 1 to _{10), - (CH 2) j} - (j is an integer of 1 to _{10), - CR '2 - (} R' is an aliphatic hydrocarbon group, an aromatic hydrocarbon A hydrogen group or 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) j - (j is an integer of 1 to 10) and -CR _'2 - (R' is an aliphatic hydrocarbon group, an aromatic hydrocarbon Represents a hydrogen group or a halogenated hydrocarbon group), and represents at least one structure selected from the group consisting of:
Ph represents a condensed aromatic ring, R ₁ to R ₂₀ may be the being the same or different, a hydrogen atom, a fluorine atom, an alkyl group, a halogenated alkyl group in which a part or wholly halogenated, At least one atom or group selected from the group consisting of allyl group, aryl group, nitro group and nitrile group is shown.

l and m represent an integer of 0 to 4, and q represents an integer of 2 or more. t shows the integer of 0-4.
n and p indicate the composition ratio of each unit, and p is a value other than 0 among 0 to 1, and n + p = 1. ].

  Furthermore, what is represented by following formula (3) as this condensed aromatic ring unit is more preferable.

[In Formula (3), D is at least one selected from the group consisting of —O— and —CR ″ ₂ — (R ″ represents an aliphatic hydrocarbon group or an aromatic hydrocarbon group). The structure is shown.
P is at least one structure selected from structures represented by the following formulas (4-1) to (4-3);
Ph is a structure represented by the following formula (5-1).

q represents an integer of 2 or more. t shows the integer of 0-4.
n and p indicate the composition ratio of each unit, and p is a value other than 0 among 0 to 1, and n + p = 1. ].
In order to improve water resistance, it is desirable to introduce more condensed aromatic ring units (as the value of p is larger). However, when more condensed ring units are introduced, the solubility of the product is remarkably lowered and handling may be difficult. In such a case, it is possible to introduce more condensed aromatic ring units by synthesizing a hydrophobic unit using two or more different condensed aromatic ring units. It is preferable that p is in the range of 0.01 to 1.

  Specific examples of such units include the following.

When the unit containing such a condensed aromatic ring is contained, the hydrophobicity is remarkably improved. For this reason, the outstanding hot water tolerance can be provided, providing the proton conductivity similar to the past.
[Unit having nitrogen-containing heterocyclic group]
The sulfonated polyarylene used in the present invention includes a unit having a main chain of a polyphenylene structure and a nitrogen-containing heterocyclic group in the side chain.

The polyphenylene structure serving as the main chain is obtained by removing the substituent R ² in the following structure, and the side chain represents the substituent R ² in the following structural formula.

In the present invention, R ² which is a side chain having a nitrogen-containing heterocyclic group is represented by the following general formula (A).

In formula (2), Z represents a direct bond or at least one structure selected from the group consisting of —O— and —S—,
Y _{is, -CO -, - SO 2 -} , - SO -, - CONH -, - COO -, - (CF 2) l '- (l' is an integer of 1 to 10), - C (CF ₃ ) ₂ - represents at least one structure selected from the group consisting of, preferably -CO-.

R ₂₁ represents a nitrogen-containing heterocyclic group. Examples of the nitrogen-containing heterocyclic group include pyrrole, thiazole, isothiazole, oxazole, isoxazole, pyridine, imidazole, imidazoline, pyrazole, 1,3,5-triazine, pyrimidine, pyritadine, pyrazine, indole, quinoline, isoquinoline, brine, Nitrogen-containing heterocyclic compounds composed of benzimidazole, benzoxazole, benzthiazole, tetrazole, tetrazine, triazole, carbazole, acridine, quinoxaline and quinazoline and groups having a structure in which a hydrogen atom bonded to carbon or nitrogen of these derivatives is extracted It is. These nitrogen-containing heterocyclic groups may have a substituent. Examples of the substituent include alkyl groups such as a methyl group, an ethyl group, and a propyl group, and aryl groups such as a phenyl group, a toluyl group, and a naphthyl group. Group, cyano group, fluorine atom and the like.

b shows the integer of 1-5, Preferably it is 1 or 2.
a represents an integer of 0 to 4, and is preferably 0 or 1.
Examples of the unit having a nitrogen-containing heterocyclic group in the side chain include a structural unit represented by the following general formula (B).

Y, Z, R ₂₁ , a, and b in the formula (B) are the same as in the formula (A). In addition, among the single lines at the ends of the structural units, those in which no substituent is displayed on one side mean connection with adjacent structural units.

When a nitrogen-containing heterocyclic group is contained in the side chain, a polymer solid electrolyte having high sulfonic acid stability at high temperatures can be obtained without impairing proton conductivity.
[Units containing side chains having sulfonic acid groups]
The sulfonated polyarylene used in the present invention has a sulfonic acid group, and such a sulfonic acid group may be substituted on any of the polyarylenes, and is substituted on the above-mentioned side chain. It may include a structural unit having a sulfonic acid group. In the present invention, the sulfonated polyarylene preferably contains a side chain having a sulfonic acid group represented by the following general formula (E).

In the formula (E), Y represents —CO—, —SO ₂ —, —SO—, —CONH—, —COO—, — (CF ₂ ) _{1 ′} — (wherein 1 ′ is an integer of 1 to 10), -C (CF _{3) 2} - represents at least one structure selected from the group consisting of. Of these, —CO— and —SO ₂ — are preferable. Z represents a direct bond or at least one structure selected from the group consisting of —O— and —S—. 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 ) _h SO ₃ H or —O (CF ₂ ) _h SO ₃ H (h 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. Aromatic group is a substituent represented by -SO ₃ H or _{-O (CH 2) h SO 3} H or _{-O (CF 2) h SO 3} H described above, must have at least one substituent In the case of a naphthyl group, it is preferable that two or more are substituted.

c is an integer of 0 to 10, preferably 0 to 2, d is an integer of 0 to 10, preferably 0 to 2, and k is an integer of 1 to 4.
As a preferable combination of the values of c and d and the structures of Y, Z and Ar,
(1) a structure in which c = 0, d = 0, Y is —CO—, and Ar is a phenyl group having —SO ₃ H as a substituent;
(2) a structure in which c = 1, d = 0, Y is —CO—, Z is —O—, and Ar is a phenyl group having —SO ₃ H as a substituent;
(3) c = 1, a d = 1, k = 1, Y is -CO-, Z is -O-, and the structure Ar is a phenyl group having a -SO ₃ H as a substituent,
(4) a c = 1, d = 0, Y is -CO-, 2 pieces of -SO ₃ as Ar is a substituted group
A structure which is a naphthyl group having H,
(5) c = 1, d = 0, Y is —CO—, Z is —O—, and Ar is a phenyl group having —O (CH ₂ ) ₄ SO ₃ H as a substituent. Examples include structures.

  The structural unit having such a sulfonic acid group is represented by the following formula (F).

In general formula (F), Y, Z, Ar, c, d, and k are the same as those in formula (E). In addition, among the single lines at the end of each structural unit, those in which no substituent is displayed on one side mean connection with adjacent structural units.

In addition, Y and Z of the said formula (A) and (E) which comprise a side chain may be the same, and may differ.
Sulfonated polyarylene The sulfonated polyarylene used in the present invention includes structural units represented by the general formulas (1) and (B). Specifically, the sulfonated polyarylene used in the present invention is represented by the structural unit (sulfonic acid unit) having a sulfonic acid group represented by the general formula (F) and the general formula (1). It is characterized by containing a structural unit (hydrophobic unit) having no sulfonic acid group and a nitrogen-containing heterocyclic group (nitrogen-containing heterocyclic aromatic unit) represented by the above general formula (B). It is a polymer represented by the formula (G). Of the single wires at the end of each structural unit, one not having a substituent displayed on one side means connection with an adjacent structural unit.

In the general formula (G), A, B, D, Y, Z, Ph, Ar, a, b, c, d, k, l, m
, N, p, q, t, and R _{1 to} R ₂₁ are A, B, D, Y, Z, Ph, Ar, a, and R in the general formulas (1), (B), and (F), respectively. b, synonymous c, d, k, l, m, n, p, q, s, t, and the R ₁ to R _21. x, y, and z indicate molar ratios when x + y + z = 100 mol%. Of the single wires at the end of each structural unit, one not having a substituent displayed on one side means connection with an adjacent structural unit.

Such a sulfonated polyarylene contains 0.5 to 99.9 mol%, preferably 10 to 99.% of the structural unit represented by the formula (F), that is, the unit of x (unit containing a side chain having a sulfonic acid group). The structural unit represented by the formula (B), that is, the unit of z (a unit containing a nitrogen-containing heterocyclic group) is 0.1 to 99.5 mol%, preferably 0.5 to 89.% in a proportion of 5 mol%. 5 mol% is contained. The structural unit represented by the formula (B), that is, the unit of y (condensed aromatic ring unit) is 99.4 to 0.01 mol%, preferably 89.5 to 0.5 mol%. desirable.

  The ratio of the structural unit represented by the formula (B), that is, the z unit to the structural unit represented by the formula (F), that is, the unit of x is 0.001 mol% to 50 mol%, preferably 0.1 mol% to 30 mol%, more preferably 1 mol% to 25 mol%.

  The ion exchange capacity of the sulfonated polyarylene used in the present invention is usually 0.3 to 5 meq / g, preferably 0.5 to 3 meq / g, and more preferably 0.8 to 2.8 meq / g. When it is 0.3 meq / g or more, proton conductivity is high and power generation performance is high. On the other hand, when it is 5 meq / g or less, a decrease in water resistance can be suppressed, which is preferable.

The above-mentioned ion exchange capacity can be adjusted by changing the types, usage ratios, and combinations of the structural unit (1), the structural unit (B), and the structural unit (F). Therefore, the charge ratio of the precursor (monomer / oligomer) that induces each structural unit (1), (B), (F) during polymerization,
It can be adjusted by changing the type.

Generally, when the structural unit (F) is increased, the ion exchange capacity is increased and the proton conductivity is increased, but the water resistance is decreased. On the other hand, when the structural unit (F) decreases, the ion exchange capacity decreases and the water resistance increases, but the proton conductivity decreases.

When the structural unit (B) is contained, the stability of the sulfonic acid group under high temperature conditions is improved, and as a result, the heat resistance is improved. Since the nitrogen atom of the nitrogen-containing heterocyclic aromatic compound has basicity, it forms an ionic interaction with the sulfonic acid group. This enhances the stability of the sulfonic acid group and suppresses the elimination of the sulfonic acid group under high temperature conditions. Similarly, the cross-linking reaction between polymer molecules derived from sulfonic acid groups can be suppressed under high temperature conditions.

The remainder excluding the components (B) and (F) in the polymer corresponds to the amount of the structural unit (1). When this structural unit (1) is contained, it becomes easy to adjust the molecular weight and the content of each structural unit, and a thermally and chemically stable polymer can be obtained. By including this structural unit (1), a hydrophobic portion can be imparted to the polymer, and since it has a condensed aromatic ring, methanol resistance can be imparted to the polymer.

The molecular weight of the sulfonated polyarylene used in the present invention 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).
<Method for producing sulfonated polyarylene>
For the production of the sulfonated polyarylene used in the present invention, for example, the following three methods, Method A, Method B and Method C, can be used.

(Method A)
For example, in the same manner as the method described in JP-A-2004-137444, the following general formula (F ′
), A monomer represented by the following general formula (B ′) and a monomer represented by the following general formula (1 ′) are copolymerized to produce a polymer having a sulfonate group, It can be synthesized by deesterifying the sulfonic acid ester group and converting the sulfonic acid ester group to a sulfonic acid group.

Monomer (F ’)

In the formula (F ′), X represents an atom or group selected from a chlorine atom, a bromine atom and —OSO ₂ Rb (where Rb represents an alkyl group, a fluorine-substituted alkyl group or an aryl group).
Y, Z, c, d and k are the same as those in formula (F), and R represents an alkyl group having 4 to 12 carbon atoms.

Ar 'is an aromatic having a -SO ₃ R or _{-O (CH 2) h SO 3} R , or -O (CF _{2) h} SO ₃ substituents represented by R (h is an integer of 1 to 12) Indicates a group.
Specific examples of the compound represented by the general formula (F ′) include compounds represented by the following general formula, JP-A Nos. 2004-137444, 2004-345997, and JP-A-200.
Examples thereof include sulfonic acid esters described in Japanese Patent No. 4-346163.

In the compound represented by the general formula (F ′), the sulfonate structure is usually bonded to the meta position of the aromatic ring.
Monomer (1 ')
The monomer (1 ′) is represented by the following formula (1 ′).

In the formula (1 ′), A, B, D, Ph, R _{1 to} R ₂₀ , l, m, n, p, q, and t are the same as those in the formula (1).
X represents a halogen atom excluding fluorine, an atom or group selected from —SO ₂ CH ₃ and —SO ₂ CF ₃ ;
Ph is preferably a group selected from a naphthalene group, an anthracene group, a tetracene group, and a pentacene group.

  The compound represented by the formula (1 ′) is more preferably a compound represented by the following formula (2 ′).

[In the formula (2 ′), A, D, Ph, R _{1 to} R ₂₀ , l, m, q, t, n, and p are the same as those in the formula (2). X represents an atom selected from halogen atoms excluding fluorine.
Furthermore, as such a compound, a compound represented by the following formula (3 ′) is preferable.

In formula (3 ′), X represents an atom selected from halogen atoms excluding fluorine. D, P, Ph, q, t, n, and p are the same as in equation (3). It is preferable that p is in the range of 0.01 to 1.
The compound represented by the above formula (1 ′) can be synthesized, for example, by the following reaction.

  First, bisphenols represented by the following formulas (1-1) and (1-2) are used as alkali metal salts.

At this time, after dissolving in a polar solvent having a high dielectric constant such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, sulfolane, diphenylsulfone, dimethylsulfoxide, an alkali metal such as lithium, sodium, potassium, Add alkali metal hydride, alkali metal hydroxide, alkali metal carbonate, etc. 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 the bisphenol is reacted with a dihalide represented by the following formula (1-3).

In formula (1-3), Hal represents a halogen atom, and a fluorine atom or a chlorine atom is particularly preferable.
Examples of bisphenols represented by the formula (1-1) include 1,3-bis [1-methyl-
1- (4-hydroxyphenyl) ethyl] benzene (Bis-M), 1,4-bis [1-methyl-1- (4-hydroxyphenyl) ethyl] benzene, 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, 4,4′-isopropylidenebiphenol (Bis-A), 2,2-bis (4-hydroxyphenyl) -1, 1,1,3,3,3-hexafluoropropane (Bis-AF), 4,
4′-bishydroxybenzophenone (4,4′-DHBP), 4,4′-bishydroxydiphenyl sulfone (4,4′-DHDS), 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxybiphenyl (4 , 4′-DHBP), bis (4-hydroxyphenyl) methane, resorcinol (RES), hydroquinone (HQ), 9,9-bis (4-hydroxyphenyl) fluorene (BPFL), 9,9-bis (4- Hydroxy-3-methylphenyl) fluorene (BCFL), 4,4′-isopropylidenebis (2-phenylphenol), 4,4′-cyclohexylidenebis (2-cyclohexylphenol) and the like. Among them, 1,3-bis [1-methyl-1- (4-hydroxyphenyl) ethyl] benzene (Bi
sm), 1,4-bis [1-methyl-1- (4-hydroxyphenyl) ethyl] benzene,
2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane (Bis-AF), resorcinol (RES), 9,9-bis (4-hydroxyphenyl) fluorene (BPFL) is preferred.

Examples of the bisphenols represented by the formula (1-2) include 1,5-dihydroxynaphthalene (1,5-NAP), 1,6-dihydroxynaphthalene (1,6-NAP), 1,7- Dihydroxynaphthalene (1,7-NAP), 2,6-dihydroxynaphthalene (2,
6-NAP), 2,7-dihydroxynaphthalene (2,7-NAP), 2,3-dihydroxynaphthalene (2,3-NAP) and the like. Among them, 2,7-dihydroxynaphthalene (2,7-NAP), 1,5-dihydroxynaphthalene (1,5-NAP), 1,6-dihydroxynaphthalene (1,6-NAP), 1,7-dihydroxy Naphthalene (1,7-
NAP) is preferred.

Examples of the dihalide represented by the formula (1-3) include 4,4′-dichlorobenzophenone (4,4′-DCBP), 4,4′-difluorobenzophenone (4,4′-DFBP), 4- Chloro-4′-fluorobenzophenone, 2-chloro-4′-fluorobenzophenone, 4,4′-dichlorodiphenylsulfone (4,4′-DCDS), 4,4′-difluorodiphenylsulfone (4,4′-DFDS) ), 2,6-dinitrobenzonitrile, 2,5-dinitrobenzonitrile, 2,4-dinitrobenzonitrile, 2,6-dichlorobenzonitrile (2,6-DCBN), 2,5-dichlorobenzonitrile (2 , 5-DCBN), 2,4-dichlorobenzonitrile (2,4-DBN), 2,6-difluorobenzonitrile (
2,6-DFBN), 2,5-difluorobenzonitrile (2,5-DFBN), 2,4-
And difluorobenzonitrile (2,4-DFBN).

  The dihalide 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 a method of adding a dichloro compound in the latter half of the reaction so that both ends are chlorine atoms.

In these reactions, the reaction temperature is 60 ° C to 300 ° C, preferably 80 ° C to 250 ° C, and the reaction time is 15 minutes to 100 hours, preferably 1 hour to 24 hours.
The obtained compound is an oligomer or a polymer, and these can be purified by a general purification method of a polymer, 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 in excess, the molecular end of the resulting compound is an aromatic chloride.

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

  The following are specific examples of aromatic compounds in which n = 0 and P and Ph are composed of two or more different types.

(In the above formulas, p ₁ and p ₂ indicate the composition ratio of each unit, and p ₁ takes a value other than 0 from 0 to 1, and p ₁ + p ₂ = 1.)
The following is a specific example of an aromatic compound in which n = 0 and P and Ph are composed of one type.

Among these aromatic compounds, the compound (1-2) includes 2,7-dihydroxynaphthalene (2,7-NAP), 1,5-dihydroxynaphthalene (1,5-NAP), 1,6- As a compound of dihydroxynaphthalene (1,6-NAP) and (1-1), 1,3-bis [
1-methyl-1- (4-hydroxyphenyl) ethyl] benzene (Bis-M), 1,4-bis [1-methyl-1- (4-hydroxyphenyl) ethyl] benzene, 2,2-bis (4 -Hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane (Bis-AF),
The compound synthesized from resorcinol (RES) is preferred.

By changing the ratio of n and p representing the composition ratio of each unit, the glass transition temperature of the polymer can be adjusted. Among these, from the viewpoint of polymer processability, a compound having a value of p = 0.1 to 1 is preferable.

Monomer (B ’)

X represents an atom or group selected from a chlorine atom or a bromine atom, and -OSO ₂ Rb (wherein Rb represents an alkyl group, a fluorine-substituted alkyl group or an aryl group).
Y, Z, R _21, a and b are as defined in the general formula (B).

  Specific examples of the monomer (B ′) include the following compounds.

Furthermore, compounds in which a chlorine atom is replaced with a bromine atom, and isomers having different bonding positions of chlorine and bromine atoms can be exemplified. In addition, a compound in which a —CO— bond is replaced with a —SO ₂ — bond can be exemplified. These compounds may be used alone or in combination of two or more.

  Examples of the method for synthesizing the monomer (B ′) include a method in which a compound represented by the following general formula (B2) and a nitrogen-containing heterocyclic compound are subjected to a nucleophilic substitution reaction.

In the formula, X, Y, a and b are the same as those defined in the general formula (B ′).
X ′ represents a halogen atom, specifically, preferably a fluorine atom or a chlorine atom, more preferably a fluorine atom.

Specific examples of the compound represented by the general formula (2) include 2,4-dichloro-4′-fluorobenzophenone, 2,5-dichloro-4′-fluorobenzophenone, and 2,6-dichloro-4′-fluoro. Benzophenone, 2,4-dichloro-2'-fluorobenzophenone, 2,5-dichloro-2'-fluorobenzophenone, 2,6-dichloro-2'-fluorobenzophenone, 2,4-dichlorophenyl-4'-fluorophenylsulfone 2,5-dichlorophenyl-4'-fluorophenylsulfone, 2,6-dichlorophenyl-4'-fluorophenylsulfone, 2,4-dichlorophenyl-2'-fluorophenylsulfone, 2,4-dichlorophenyl-2'-fluoro Phenylsulfone, 2,4-dichlorophenyl-2′-fluorophenylsulfone.
Of these compounds, 2,5-dichloro-4'-fluorobenzophenone is preferred.

The nitrogen-containing heterocyclic compound has active hydrogen, and this active hydrogen is subjected to a substitution reaction with the group represented by X ′ of the compound represented by the general formula (2).
Examples of nitrogen-containing heterocyclic compounds having active hydrogen include pyrrole, thiazole, isothiazole, oxazole, isoxazole, pyridine, imidazole, imidazoline, pyrazole, 1,3,5-triazine, pyrimidine, pyritazine, pyrazine, indole, quinoline, Isoquinoline, bromine, benzimidazole, benzoxazole, benzthiazole, tetrazole, tetrazine, triazole, carbazole, acridine, quinoxaline, quinazoline, 2-hydroxypyridine, 3-hydroxypyridine, 4-hydroxypyridine, 3-hydroxyquinoline, 8-hydroxy Quinoline, 2-hydroxypyrimidine, 2-mercaptopyridine, 3-mercaptopyridine, 4-mercaptopyridine, 2-mercaptopyrimidine, 2-me , And the like mercapto benzthiazole.

Of these compounds, pyrrole, imidazole, indole, carbazole, benzoxazole, and benzimidazole are preferable.
The reaction between the compound represented by the general formula (2) and the nitrogen-containing heterocyclic compound having active hydrogen is preferably performed in an organic solvent. A polar solvent such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, sulfolane, diphenylsulfone, dimethylsulfoxide is used. In order to accelerate the reaction, alkali metal, alkali metal hydride, alkali metal hydroxide, alkali metal carbonate, or the like is used. The ratio of the compound represented by the general formula (2) to the nitrogen-containing heterocyclic compound having active hydrogen is such that the nitrogen-containing heterocyclic compound having equimolar or active hydrogen is added in excess. Specifically, the nitrogen-containing heterocyclic compound having active hydrogen is preferably used in an amount of 1 to 3 times mol, particularly 1 to 1.5 times mol of the compound represented by the general formula (2).

The reaction temperature is 0 ° C to 300 ° C, preferably 10 ° C to 200 ° C. The reaction time is 15 minutes to 100 hours, preferably 1 hour to 24 hours. The product is preferably used after being purified by a method such as recrystallization.
Polymerization method When producing the sulfonated polyarylene, the monomer (1 ′) and the monomer (B ′)
And a monomer (F ′) are copolymerized to obtain a precursor.

This copolymerization is carried out in the presence of a catalyst. The catalyst used at this time is a catalyst system containing a transition metal compound, and this catalyst system is (1) a transition metal salt and a ligand. Compound(
Hereinafter, it is referred to as “ligand component”. ), Or transition metal complexes with ligands coordinated (including copper salts)
As well as (2) a reducing agent as an essential component, and in order to further increase the polymerization rate, a “salt” may be added.

  As specific examples of these catalyst components, the use ratio of each component, reaction solvent, concentration, temperature, time, and other polymerization conditions, the compounds and conditions described in JP-A No. 2001-342241 can be employed.

For example, as the transition metal salt, nickel chloride, nickel bromide and the like are preferably used, and as the compound serving as a ligand, triphenylphosphine, tri-o-tolylphosphine, tri-m-tolylphosphine, Tri-p-tolylphosphine, tributylphosphine, tri-tert-butylphosphine, trioctylphosphine, 2,2'-bipyridine and the like are preferably used. Furthermore, nickel chloride bis (triphenylphosphine) and nickel chloride (2,2′bipyridine) are preferably used as the transition metal (salt) in which the ligand is coordinated in advance. Examples of the reducing agent include iron, zinc, manganese, aluminum, magnesium, sodium, and calcium, and zinc, magnesium, and manganese are preferable. As the “salt”, sodium bromide, sodium iodide, potassium bromide, tetraethylammonium bromide, and tetraethylammonium iodide are preferable. A polymerization solvent may be used for the reaction, and specifically, tetrahydrofuran, N, N-dimethylformamide, N, N-dimethylacetamide, 1-methyl-2-pyrrolidone and the like are preferably used.

  The proportion of each component used in the catalyst system is usually from 0.0001 to 10 mol, preferably from 0.0001 to 10 mol, based on 1 mol of the total amount of monomers of the transition metal salt or the transition metal (salt) coordinated with the ligand. 01-0.5 mol. If it exists in this range, it can polymerize with high catalyst activity and high molecular weight. When “salt” is used in the catalyst system, the amount used is generally 0.001 to 100 mol, preferably 0.01 to 1 mol, per 1 mol of the total amount of monomers. Within such a range, the effect of increasing the polymerization rate is sufficient. The total concentration of monomers in the polymerization solvent is usually 1 to 90% by weight, preferably 5 to 40% by weight. Moreover, the polymerization temperature at the time of superposing | polymerizing the polymer of this invention is 0-200 degreeC normally, Preferably it is 50-100 degreeC. The polymerization time is usually 0.5 to 100 hours, preferably 1 to 40 hours.

Next, the obtained polymer is hydrolyzed to convert the sulfonic acid ester group (—SO ₃ R) in the structural unit into a sulfonic acid group (—SO ₃ H).
Hydrolysis includes (1) a method in which the polymer having a sulfonic acid ester group is added to an excess amount of water or alcohol containing a small amount of hydrochloric acid, and the mixture is stirred for 5 minutes or longer. (2) the sulfone is added in trifluoroacetic acid. a method of reacting about 5 to 10 hours at a temperature of about 80 to 120 ° C. the polymer having an ester group, (3) sulfonic acid ester group in the polymer (-SO ₃ R) 1 to 3 relative to 1 mole of After the polymer having a sulfonic acid ester group is reacted at a temperature of about 80 to 150 ° C. for about 3 to 10 hours in a solution containing double moles of lithium bromide, such as N-methylpyrrolidone, hydrochloric acid is added. It can be performed by the method of doing.

In addition to the above method, for example, similarly to the method described in JP-A No. 2001-342241, it has a skeleton represented by the above general formula (F ′) and has a sulfonic acid group and a sulfonic acid ester group. The monomer (1 ′) and the monomer (B ′) are copolymerized, and the polymer can be synthesized by sulfonation using a sulfonating agent (this is Method B). Called).

  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 (F ′) that can be used in Method B, JP-A-2001-342241 And dihalides described in JP-A-2002-29389.

In addition to the above method, in the general formula (F ′), Ar is an aromatic group having a substituent represented by —O (CH ₂ ) _h SO ₃ H or —O (CF ₂ ) _h SO ₃ H. In this case, for example, as in the method described in JP-A-2005-606254, a precursor monomer that can be a structural unit represented by the general formula (F ′) and the general formula (1) A monomer or oligomer that can be a structural unit (monomer or oligomer of formula (1 ′)) and a monomer that is a structural unit represented by general formula (B) (monomer of formula (B ′)) Then, it can also be synthesized by introducing an alkyl sulfonic acid or a fluorine-substituted alkyl sulfonic acid (this is called C method).

  As specific examples of precursor monomers that can be used in (Method C) and can be structural units represented by the above general formula (F ′), dihalides described in JP-A-2005-36125 Can be mentioned. Specifically, 2,5-dichloro-4′-hydroxybenzophenone, 2,4-dichloro-4′-hydroxybenzophenone, 2,6-dichloro-4′-hydroxybenzophenone, 2,5-dichloro-2 ′, Examples thereof include 4′-dihydroxybenzophenone and 2,4-dichloro-2 ′, 4′-dihydroxybenzophenone. Moreover, the compound which protected the hydroxyl group of these compounds by the tetrahydropyranyl group etc. can be mention | raise | lifted. Further, those in which a hydroxyl group is replaced with a thiol group and those in which a chlorine atom is replaced with a bromine atom or an iodine atom can also be mentioned.

In (Method C), an alkylsulfonic acid group is introduced into a polymer (having no sulfonic acid group) by the method described in JP-A-2005-60625. For example, it can be introduced by reacting the hydroxyl group of the precursor polymer with propane sultone, butane sultone, or the like.
<Additives>
In addition to the sulfonated polyarylene, the electrode electrolyte for a polymer electrolyte fuel cell of the present invention includes an antioxidant, an inorganic acid such as sulfuric acid and phosphoric acid, phosphate glass, tungstic acid, phosphate hydrate, β- Inorganic proton conductor particles such as alumina proton substitution products, proton-introduced oxides,
An organic acid containing a carboxylic acid, an organic acid containing a sulfonic acid, an organic acid containing a phosphonic acid, an appropriate amount of water, or the like may be added.

  As the antioxidant, a hindered phenol compound having a molecular weight of 500 or more is preferable. By containing such an antioxidant, durability as an electrolyte can be further improved.

Examples of the hindered phenol compound include triethylene glycol-bis [3- (
3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate] (trade name: IRGANOX 245), 1,6-hexanediol-bis [3- (3,5-di-tert-butyl-4-hydroxy) Phenyl) propionate] (trade name: IRGANOX 259), 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -3,5-triazine (trade name) : IRGANOX 565), pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] (trade name: IRGANOX 1010), 2,2-thio-diethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] (trade name: IRGANOX 1035), octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate) Name: IRGANOX 1076), N, N-hexamethyl Nbisu (3,5
Di-t-butyl-4-hydroxy-hydrocinnamamide) (IRGAONOX 1098) 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) ) Benzene (trade name: IRGANOX 1330), tris- (3,5-di-t-butyl-4-hydroxybenzyl) -isocyanurate (trade name: IRGANOX 3114), 3,9-bis [2- [3 -(3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane (trade name: Sumilizer G
A-80).

  The amount of the additive added to the polymer electrolyte fuel cell electrode electrolyte of the present invention is not particularly limited, and the oxidation resistance, proton conductivity, strength and elasticity required for the polymer electrolyte fuel cell electrode electrolyte are not limited. An optimal amount may be used depending on the rate. For example, it is desirable that the total weight of the additive is 0.001 to 30 parts by weight, preferably 0.01 to 10 parts by weight with respect to 100 parts by weight of the sulfonated polyarylene. Moreover, an additive may be used independently or may use 2 or more types together.

[Electrode paste and electrode varnish]
The electrode varnish of the present invention is obtained by dispersing or dissolving the above-mentioned polymer electrolyte fuel cell electrode electrolyte in a solvent, and the electrode paste is a paste containing the above-mentioned electrode electrolyte, catalyst particles and solvent, and is necessary for these. Depending on the case, other components such as a dispersant and carbon fiber may be included.

<Catalyst particles>
The catalyst particles consist of a catalyst supported on carbon or a metal oxide carrier, 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 used in the electrode varnish and electrode paste of the present invention is not particularly limited as long as it is a solvent that dissolves or disperses the above-described polymer electrolyte fuel cell electrode electrolyte. Moreover, you may use individually by 1 type or in combination of 2 or more types. If a varnish prepared by dissolving the electrode electrolyte for a polymer electrolyte fuel cell in the following solvent is prepared before mixing with an electrode material such as a catalyst to prepare a paste, handling becomes easy.

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-octano , 2-octanol, 2-ethyl-1-hexanol, 2-methoxyethanol, 2-ethoxyethanol, 2- (methoxymethoxy) ethanol, 2-isopropoxyethanol, 1-methoxy-2-propanol, 1-ethoxy Alcohols such as 2-propanol; 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 (2-ethoxyethyl) ether, cineol, benzylethylether, anisole, phene Ethers such as alcohol and acetal; acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone, cyclopentanone, cyclohexanone, 2-hexanone, 4-methyl-2-pentanone, 2-heptanone, 2,4-dimethyl-3 Ketones such as pentanone and 2-octanone; γ-butyrolactone, ethyl acetate, propyl acetate, n-butyl acetate, isobutyl acetate, sec-butyl acetate, pentyl acetate, isopentyl acetate, 3-methoxypropyl acetate, 3-methoxy Esters such as butyl acetate, methyl butyrate, ethyl butyrate, methyl lactate, ethyl lactate, butyl lactate; dimethyl sulfoxide, N-methylformamide, N, N-dimethylformamide, N, N-diethylformamide, N, N-dimethylacetamide N-methyl-2 Pyrrolidone, aprotic polar solvents such as tetramethylurea; toluene, xylene, heptane, hexane, heptane, etc. hydrocarbon solvents such as octane.

Of the above solvents, those which are poor solvents for the proton conducting membrane in a mixed solvent system of water are particularly desirable. The combination of the electrode electrolyte and the solvent system is suitable for mass production of MEAs because the electrode paste can be applied to the proton conducting membrane. Preferred solvents for use with water include methanol, ethanol, n-propyl alcohol, 2-propanol, dioxane, tetrahydrofuran, tetrahydropyran, diisopropyl ether, di-n-propyl ether, methyl ethyl ketone, 2-pentanone, 3-pentanone, cyclohexane. Pentanone, cyclohexanone, 2-hexanone, 4-methyl-2-pentanone, 2-heptanone, γ-butyrolactone, ethyl acetate, propyl acetate, n-butyl acetate, isobutyl acetate, sec-butyl acetate, 3-methoxypropyl acetate 3-methoxybutyl acetate, dimethyl sulfoxide, N-methylformamide, N, N-dimethylformamide, N, N-diethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone It can be suitably used. The mixed solvent may be a mixture of one kind of solvent and water, or a plurality of solvents and water.

<Dispersant>
You may add a dispersing agent to the electrode paste and varnish of this invention as needed. Examples of such a dispersant include surfactants such as an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant.

  Examples of the anionic surfactant include oleic acid / N-methyltaurine, potassium oleate / diethanolamine salt, alkyl ether sulfate / triethanolamine salt, polyoxyethylene alkyl ether sulfate / triethanolamine salt, special modified polyether Amine salt of 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 ester, high molecular weight polyester acid amide amine salt, special fatty acid derivative Amidoamine salt, alkylamine salt of higher fatty acid, amidoamine salt of high molecular weight polycarboxylic acid, sodium laurate, sodium stearate, sodium oleyl sulfate sodium salt, cetyl Sulfate sodium salt, stearyl sulfate sodium salt, oleyl sulfate sodium salt, lauryl ether sulfate sodium salt, alkylbenzene sulfonate sodium, oil-soluble alkylbenzene sulfonate, α-olefin sulfonate, higher alcohol phosphate monoester disodium Salt, higher alcohol phosphoric acid diester disodium salt, zinc dialkyldithiophosphate and the like.

  Examples of the cationic surfactant include benzyldimethyl {2- [2- (P-1,1,3,3-tetramethylbutylphenoxy) ethoxy] ethyl} ammonium chloride, octadecylamine acetate, tetradecylamine. Acetate, octadecyltrimethylammonium chloride, tallow trimethylammonium chloride, dodecyltrimethylammonium chloride, coconut trimethylammonium chloride, hexadecyltrimethylammonium chloride, behenyltrimethylammonium chloride, coconut dimethylbenzylammonium chloride, tetradecyldimethylbenzylammonium chloride, octadecyldimethylbenzyl Ammonium chloride, dioleyldimethylammonium chloride, 1-hydro Xyethyl-2-tallow imidazoline quaternary salt, 2-heptadecenyl-hydroxyethyl imidazoline, stearamide ethyl diethylamine acetate, stearamide ethyl diethylamine hydrochloride, triethanolamine monostearate formate, alkyl pyridium salt, higher alkyl Examples include amine ethylene oxide adducts, polyacrylamide amine salts, modified polyacrylamide amine salts, and perfluoroalkyl quaternary ammonium iodides.

Examples of the amphoteric surfactant include dimethyl coconut betaine, dimethyl lauryl betaine, sodium laurylaminoethylglycine, sodium laurylaminopropionate, stearyl dimethyl betaine, lauryl dihydroxyethyl betaine, amide betaine, imidazolinium betaine, lecithin, 3 -[Ω-fluoroaccanoyl-N-ethylamino] -1-propanesulfonic acid sodium, N- [3- (perfluorooctanesulfonamido) propyl] -N, N-dimethyl-N-carboxymethyleneammonium betaine, etc. Can be mentioned.

Examples of the nonionic surfactant include coconut fatty acid diethanolamide (1: 2).
Type), coconut fatty acid diethanolamide (1: 1 type), bovine 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, dihydroxyethyl lauryl Amine oxide, perfluoroalkylamine oxide, polyvinylpyrrolidone, higher alcohol ethylene oxide adduct,
Examples include alkylphenol ethylene oxide adduct, fatty acid ethylene oxide adduct, polypropylene glycol ethylene oxide adduct, fatty acid ester of glycerin, fatty acid ester of pentaerythrit, fatty acid ester of sorbit, fatty acid ester of sorbitan, fatty acid ester of sugar, and the like.

  The above surfactants may be used singly or in combination of two or more. Among the above surfactants, 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.

When the above dispersant is added to the electrode paste or varnish of the present invention, the power generation characteristics, storage stability and fluidity are excellent, and the productivity during coating is improved.
<Carbon fiber>
Carbon fiber can be further added to the electrode paste of the present invention as necessary. As such carbon fiber, rayon-based carbon fiber, PAN-based carbon fiber, lignin pover-based carbon fiber, pitch-based carbon fiber, vapor-grown carbon fiber, etc. can be used, preferably vapor-grown carbon fiber. is there.

  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>
Other components can be added to the electrode paste or varnish of the present invention as required. 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 content of the catalyst particles is 1 to 20% by weight, preferably 3 to 15% by weight with respect to the total amount of the electrode paste of the present invention, and the content of the polymer electrolyte fuel cell electrode electrolyte is 0.5 to 30%. % By weight, preferably 1-15% by weight, and the solvent content is 50-95% by weight, preferably 70-90% by weight. The content of the dispersant used as necessary is 0 to 10% by weight, preferably 0 to 2% by weight, and the content of carbon fiber is 0 to 20% by weight, preferably 1 to 10% by weight. is there. The total content of the above components does not exceed 100% by weight.

  If the content of the catalyst particles is 1% by weight or more, the electrode reaction rate can be increased, and if the content is 20% by weight or less, the viscosity of the electrode paste is not too high, so that uneven coating is also suppressed during coating. .

When the content of the electrode electrolyte is 0.5% by weight or more, a material having high proton conductivity is obtained, and the electrode electrolyte itself serves as a binder, so that the electrode can be easily produced. Moreover, the pore volume in an electrode can be maintained high as it is 30 weight% or less.

When the content of the solvent is in the range of 50 to 95% by weight, a sufficient pore volume in the electrode necessary for power generation can be secured, and it is suitable for handling as a paste or varnish.
When the content of the dispersant is in the range of 0 to 10% by weight, an electrode paste or an electrode paste having excellent storage stability can be obtained.

When the content of the carbon fiber is in the range of 0 to 20% by weight, a decrease in the electrode reaction rate can be suppressed.
<Preparation of paste and varnish>
The electrode paste and electrode varnish of the present invention can be prepared, for example, by mixing the above components so as to have the above contents and kneading them by a conventionally known method.

  The order of mixing the components is not particularly limited. For example, all the 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 the dispersant is added as necessary. It is preferable to stir for a certain period of time. Moreover, you may adjust the quantity of a solvent as needed and may adjust the viscosity of a paste.

[Fuel cell electrode]
The electrode for a polymer electrolyte fuel cell according to the present invention is obtained by applying the electrode paste on a transfer substrate and removing the solvent. That is, the electrode of the present invention includes the above-mentioned electrode electrolyte for a polymer electrolyte fuel cell of the present invention and the above catalyst particles.

  As the transfer substrate, a sheet made of a fluorine-based polymer such as polytetrafluoroethylene (PTFE), a glass plate treated with a release agent, a metal plate, a sheet of polyethylene terephthalate (PET) or the like may be used. it can.

  Examples of methods for applying the electrode paste onto the transfer substrate include brush coating, brush coating, bar coater coating, knife coater coating, doctor blade method, screen printing, and spray coating.

In addition, an electrode paste containing the above polymer electrolyte fuel cell electrode electrolyte may be directly applied to a proton conductive membrane, a gas diffusion layer, or carbon paper.
[Membrane-electrode assembly]
In the membrane-electrode assembly (hereinafter also referred to as “MEA”) of the present invention, the electrode is provided on at least one surface of a solid polymer electrolyte membrane, and the electrode layer formed on the transfer substrate is used as the electrolyte. It is obtained by transferring to at least one side, preferably both sides, of the film.

  The solid polymer electrolyte membrane is not particularly limited as long as it is a proton conductive solid polymer membrane. For example, electrolyte membrane made of perfluoroalkyl sulfonic acid polymer such as Nafion (DuPont), Flemion (Asahi Glass), Aciplex (Asahi Kasei), etc .; perfluoroalkyl sulfonic acid polymer, polytetrafluoroethylene fiber and porous Reinforced electrolyte membrane combined with membrane; electrolyte membrane made of partially fluorinated sulfonated polymer such as polytetrafluoroethylene graft sulfonated polystyrene; sulfonated polyarylene, sulfonated polyphenylene, sulfonated polyetherketone, sulfonated polyether Aromatics such as sulfone, sulfonated polyether nitrile, sulfonated polyphenylene ether, sulfonated polyphenylene sulfide, sulfonated polybenzimidazole, sulfonated polybenzoxazole, sulfonated polybenzthiazole Electrolyte membranes made of sulfonated polymers; electrolyte membranes made of aliphatic sulfonated polymers such as sulfonated polystyrene and sulfonic acid-containing acrylic polymers; pore filling type electrolyte membranes made by combining these with porous membranes; polybenzoxazole, Examples thereof include an electrolyte membrane made of an acid-impregnated polymer obtained by impregnating a polymer such as polybenzimidazole or polybenzthiazole with phosphoric acid or sulfuric acid. Among these, an electrolyte membrane made of an aromatic sulfonated polymer is preferable.

In the case of producing a polymer electrolyte fuel cell, the sulfone containing the structural units (1), (B) and (F) described above has excellent proton conductivity, hot water resistance and processability. The polymer electrolyte fuel cell electrode electrolyte obtained from the modified polyarylene and the solid polymer electrolyte membrane are preferably used.

Transfer of the electrode layer to the electrolyte membrane can be performed by a hot press method. The hot press method is a method in which an electrode paste is applied to carbon paper or a release sheet, and the electrode paste application surface and the electrolyte membrane are pressure-bonded. Hot pressing is usually performed at a temperature range of 50 to 250 ° C. and a pressure of 10 to 500 kg / cm ² for 1 to 180 minutes.

  As another method for obtaining the MEA of the present invention, the MEA may be produced after forming the electrode layer directly on the proton conducting membrane, the gas diffusion layer, or the carbon paper. At this time, there is no restriction | limiting in particular in the order of application | coating and drying.

  For example, after forming an electrolyte membrane by applying a polymer electrolyte solution on a substrate such as a PET film and drying, the electrode paste is applied on the electrolyte membrane and dried to remove the solvent To form an electrode layer. Next, the MEA in which the electrode layers are formed on both surfaces of the electrolyte membrane is obtained by removing the base material, applying the electrode paste to the other surface of the electrolyte membrane, and removing the solvent.

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 3.0 mg / cm ² per unit area. It is desirable to exist in the electrode layer in the range of ² . If it is in the range of 0.05 to 4.0 mg / cm ² , sufficiently high catalytic activity is exhibited, and protons can be efficiently conducted.

The pore volume of the electrode layer is desirably in the range of 0.05 to 4.0 ml / g, preferably 0.1 to 3.0 ml / g.
[Example]
EXAMPLES The present invention will be specifically described below with reference to examples. However, the present invention is not limited to the following examples. The preparation of the membrane for evaluation and the measurement of the sulfonic acid equivalent, the molecular weight and the proton conductivity were carried out as follows.
<Preparation of membrane>
When preparing a proton conducting membrane composed of the nitrogen-containing heterocyclic aromatic compound and the sulfonated polymer described in the examples, a predetermined amount of the nitrogen-containing heterocyclic aromatic compound and the resulting sulfonated arylene were in solution. A varnish was prepared by dissolving in methanol / NMP = 1/3 (volume ratio) so as to be weight%. A cast film was prepared by a casting method in the same manner as described above, and the remaining NMP in the film was removed by dilution by immersion in a large amount of distilled water to obtain the desired film (film thickness 30 μm).
<Sulphonic acid equivalent>
The obtained polymer having a sulfonic acid group is washed until the washing water becomes neutral, and the acid remaining free is sufficiently washed with water. After drying, a predetermined amount is weighed, and THF / water Titration was performed using a standard solution of NaOH using phenolphthalein dissolved in a mixed solvent as an indicator, and the sulfonic acid equivalent was determined from the neutralization point.
<Measurement of molecular weight>
A polymer having no sulfonic acid group has a weight average molecular weight of tetrahydrofuran (T
The molecular weight in terms of polystyrene was determined by GPC using HF).

The molecular weight of a polymer having a sulfonic acid group, or the molecular weight of a polymer having a sulfonic acid group after a heat resistance test, is 7.83 g of lithium bromide, 3.3 ml of phosphoric acid, and N-methyl-2-pyrrolidone (NMP) 2 L. The molecular weight in terms of polystyrene was determined by GPC using a mixed solution consisting of
<Measurement of proton conductivity>
The AC resistance is a platinum wire (φ = 0.5 mm) pressed against the surface of a strip-shaped film sample with a width of 5 mm,
The sample was held in a constant temperature and humidity apparatus, and obtained from AC impedance measurement between 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 impedance was measured. The slope between each resistance line was measured from the AC impedance, the specific resistance of the membrane was calculated from the distance between the lines and the slope between the resistance lines, and the proton conductivity was calculated from the reciprocal of the specific resistance and the film thickness.

Specific resistance R (Ω · cm) = 0.5 (cm) × film thickness (cm) × resistance-to-resistance gradient (Ω / cm)
<Evaluation of heat resistance>
Each film having a thickness of about 40 μm was placed in a 160 ° C. oven for 24 hours. The sample before and after the heat resistance test was immersed in and dissolved in 99.8 parts by weight of the above-described NMP-based GPC eluent, and then the insoluble matter was removed and GPC measurement was performed. The insoluble content was determined from the ratio of the elution area of GPC before and after the heat test.
<Hot water resistance test>
A sulfonated polymer film having a thickness of 30 μm is cut into a length of 3 cm and a width of 4 cm, and the weight (A) is measured. In a pressure cooker, immerse the cut sample in pure water at 120 ° C for 24 hours.
Heat for hours. After cooling, after cooling, the sample is taken out, and water droplets adhering to the surface are removed with Ben Cotton (manufactured by Asahi Kasei). The weight (B) after removing the water droplets is measured, and the water content is calculated according to the following formula.

(Moisture content%) = (B−A) / A × 100
[Synthesis Example 1]
(1) Synthesis of hydrophobic unit 30.8 g of 2,7-dihydroxynaphthalene (2,7-NAP) in a 3 L separable three-necked flask equipped with a stirring blade, thermometer, nitrogen introduction tube, Dean-Stark tube, and cooling tube
(192 mmol), 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane (Bis-AF) 96.8 g (288 mmol), 2,6
-92.9 g (540 mmol) of dichlorobenzonitrile (2,6-DBN) and 86.2 g (624 mol) of potassium carbonate were weighed. After vacuum drying under reduced pressure, 675 mL of sulfolane and 270 mL of toluene were added, and the mixture was heated to reflux at 130 ° 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, and then 31.0 g (180 mmol) of 2,6-dichlorobenzonitrile (2,6-DBN) 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 methanol / hydrochloric acid aqueous solution 3.0 L / 0.3 L 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 0.4 kg of tetrahydrofuran. This solution was poured into 3.0 L of methanol and reprecipitated. The coagulated product was filtered and dried under vacuum to obtain 144 g (yield 80%) of the desired product. The number average molecular weight (Mn) in terms of polystyrene determined by GPC was 5600, and the weight average molecular weight (Mw) was 7400. It was confirmed that the obtained compound was an oligomer represented by the formula (1-a).

(2) Synthesis of copolymer In a 500 mL three-necked flask equipped with a stirrer, a thermometer, and a nitrogen introduction tube, 3- (2,5
-Dichlorobenzoyl) benzenesulfonic acid neopentyl 37.67 g (93.9 mmol), 2,5-dichloro-4 '-(1-imidazolyl) benzophenone 1.49 g (4.
7 mmol, 11.5 g of the hydrophobic unit (1-a) obtained in Synthesis Example 1- (1) (1.
4 mmol), bis (triphenylphosphine) nickel dichloride 2.62 g (4.0 mmol), sodium iodide 0.45 g (3.0 mmol), triphenylphosphine 10.
49 g (40 mmol) and 15.69 g (240 mmol) of zinc were weighed and replaced with dry nitrogen. To this was added 152 mL of N, N-dimethylacetamide (DMAc), and stirring was continued for 3 hours while maintaining the reaction temperature at 80 ° C. Then, 349 mL of DMAc was added for dilution, 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 32.6 g (375.5 mmol) of lithium bromide was added. The solution was stirred for 7 hours and then poured into 2.0 L of acetone to precipitate the product. Subsequently, after washing in order of 1N hydrochloric acid and pure water, it was dried to obtain 48 g of the desired polymer. The weight average molecular weight (Mw) of the obtained polymer was 163,000. It was confirmed that the obtained compound was a polymer represented by the formula (1-b).

A 20 wt% N-methylpyrrolidone (NMP) / methanol solution (3/1 weight ratio) of the obtained sulfonated polymer was cast on a glass plate to form a film having a thickness of 30 μm. The ion exchange capacity was 2.38 (meq / g). Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.
[Synthesis Example 2]
96.8 g (288 mmol) of 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane (Bis-AF) of Synthesis Example 1 was added to 1,3-bis [1 -Methyl-1- (4-hydroxyphenyl) ethyl] benzene (Bis-M) 99.8 g (2
88 mmol) except that the hydrophobic unit (2-a) was synthesized in the same manner as in Synthesis Example 1, and the resulting hydrophobic unit was used to synthesize in the same manner as in Synthesis Example 1, A polymer of (2-b) was obtained. A film having a thickness of 30 μm was obtained by forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Synthesis Example 3]
96.8 g (288 mmol) of 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane (Bis-AF) of Synthesis Example 1 was resorcinol (
Res) A hydrophobic unit (3-a) was synthesized in the same manner as in Synthesis Example 1 except that the amount was changed to 31.7 g (288 mmol), and the same method as in Synthesis Example 1 was performed using the obtained hydrophobic unit. And a polymer of the formula (3-b) was obtained. A film having a thickness of 30 μm was obtained by forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Synthesis Example 4]
30.8 g (192 mmol) of 2,7-dihydroxynaphthalene (2,7-NAP) of Synthesis Example 1 was replaced with 30.8 g (192 mm) of 1,5-dihydroxynaphthalene (1,5-NAP)
ol) except that the hydrophobic unit (4-a) was synthesized in the same manner as in Synthesis Example 1, and the resulting hydrophobic unit was used to synthesize in the same manner as in Synthesis Example 1, A polymer of (4-b) was obtained. A film having a thickness of 30 μm was obtained by forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Synthesis Example 5]
30.8 g (192 mmol) of 2,7-dihydroxynaphthalene (2,7-NAP) of Synthesis Example 1 was replaced with 30.8 g (192 mm) of 1,5-dihydroxynaphthalene (1,5-NAP)
ol), 96.8 g (288 mmol) of 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane (Bis-AF) and 1,3-bis [1 -Methyl-1- (4-hydroxyphenyl) ethyl] benzene (Bis-M) 99.8 g (28
Except for the change, the hydrophobic unit (5-a) was synthesized in the same manner as in Synthesis Example 1, and the resulting hydrophobic unit was used to synthesize in the same manner as in Synthesis Example 1 to obtain the formula ( A polymer of 5-b) was obtained. A film having a thickness of 30 μm was obtained by forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Synthesis Example 6]
30.8 g (192 mmol) of 2,7-dihydroxynaphthalene (2,7-NAP) of Synthesis Example 1 was replaced with 30.8 g (192 mm) of 1,6-dihydroxynaphthalene (1,6-NAP)
ol) except that the hydrophobic unit (6-a) was synthesized in the same manner as in Synthesis Example 1, and the resulting hydrophobic unit was used to synthesize in the same manner as in Synthesis Example 1. A polymer (6-b) was obtained. A film having a thickness of 30 μm was obtained by forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Synthesis Example 7]
30.8 g (192 mmol) of 2,7-dihydroxynaphthalene (2,7-NAP) of Synthesis Example 1 was replaced with 30.8 g (192 mm) of 1,6-dihydroxynaphthalene (1,6-NAP)
ol), 96.8 g (288 mmol) of 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane (Bis-AF) and 1,3-bis [1 -Methyl-1- (4-hydroxyphenyl) ethyl] benzene (Bis-M) 99.8 g (28
Except for the change, the hydrophobic unit (7-a) was synthesized in the same manner as in Synthesis Example 1, and the resulting hydrophobic unit was used to synthesize in the same manner as in Synthesis Example 1 to obtain the formula ( The polymer of 7-b) was obtained. A film having a thickness of 30 μm was obtained by forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Synthesis Example 8]
92.9 g (540 mmol) of 2,6-dichlorobenzonitrile (2,6-DBN) of Synthesis Example 1 was converted to 135.6 g (540) of 4,4′-dichlorobenzophenone (4,4′-DBP).
In addition, 31.0 g (180 mmol) of 2,6-dichlorobenzonitrile (2,6-DBN) to be added additionally was added to 4,4′-dichlorobenzophenone (4,4′-DBP).
) The hydrophobic unit (8-a) was synthesized in the same manner as in Synthesis Example 1 except that the amount was changed to 45.2 g (180 mmol), and the obtained hydrophobic unit was used in the same manner as in Synthesis Example 1. Synthesis was performed to obtain a polymer of formula (8-b). The obtained polymer was treated in the same manner as in Synthesis Example 1 with NMP /
A film having a thickness of 30 μm was obtained by forming a film from methanol. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Synthesis Example 9]
30.8 g (192 mmol) of 2,7-dihydroxynaphthalene (2,7-NAP) of Synthesis Example 1 was replaced with 30.8 g (192 mm) of 1,5-dihydroxynaphthalene (1,5-NAP)
ol), 92.9 g (540 mm) of 2,6-dichlorobenzonitrile (2,6-DBN).
ol) 135.6 g (540) of 4,4′-dichlorobenzophenone (4,4′-DBP)
In addition, 31.0 g (180 mmol) of 2,6-dichlorobenzonitrile (2,6-DBN) to be added additionally was added to 4,4′-dichlorobenzophenone (4,4′-DBP).
) A hydrophobic unit (9-a) was synthesized in the same manner as in Synthesis Example 1 except that the amount was changed to 45.2 g (180 mmol), and the obtained hydrophobic unit was used in the same manner as in Synthesis Example 1. Synthesis was performed to obtain a polymer of formula (9-b). The obtained polymer was treated in the same manner as in Synthesis Example 1 with NMP /
A film having a thickness of 30 μm was obtained by forming a film from methanol. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Synthesis Example 10]
30.8 g (192 mmol) of 2,7-dihydroxynaphthalene (2,7-NAP) of Synthesis Example 1 was replaced with 30.8 g (192 mm) of 1,6-dihydroxynaphthalene (1,6-NAP)
ol), 92.9 g (540 mm) of 2,6-dichlorobenzonitrile (2,6-DBN).
ol) 135.6 g (540) of 4,4′-dichlorobenzophenone (4,4′-DBP)
In addition, 31.0 g (180 mmol) of 2,6-dichlorobenzonitrile (2,6-DBN) to be added additionally was added to 4,4′-dichlorobenzophenone (4,4′-DBP).
) A hydrophobic unit (10-a) was synthesized in the same manner as in Synthesis Example 1 except that the amount was changed to 45.2 g (180 mmol), and the obtained hydrophobic unit was used in the same manner as in Synthesis Example 1. Synthesis was performed to obtain a polymer of formula (10-b). A film having a thickness of 30 μm was obtained by forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Synthesis Example 11]
30.8 g (192 mmol) of 2,7-dihydroxynaphthalene (2,7-NAP) of Synthesis Example 1 and 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoro Instead of using 96.8 g (288 mmol) of propane (Bis-AF),
2,7-dihydroxynaphthalene (2,7-NAP) 23.1 g (144 mmol), 1
, 5-Dihydroxynaphthalene (1,5-NAP) 23.1 g (144 mmol), 2,
In the same manner as in Synthesis Example 1, except that 64.6 g (192 mmol) of 2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane (Bis-AF) was used. Hydrophobic unit (11-a) was synthesized and synthesized using the obtained hydrophobic unit in the same manner as in Synthesis Example 1 to obtain a polymer of formula (11-b). A film having a thickness of 30 μm was obtained by forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Synthesis Example 12]
Instead of 23.1 g (144 mmol) of 2,7-dihydroxynaphthalene (2,7-NAP) in Synthesis Example 11, 23.1 g of 1,6-dihydroxynaphthalene (1,6-NAP)
(144 mmol) except that it was used, the hydrophobic unit (12-a) was synthesized in the same manner as in Synthesis Example 11, and the resulting hydrophobic unit was used to synthesize in the same manner as in Synthesis Example 1 to obtain the formula (12
A polymer of -b) was obtained. A film having a thickness of 30 μm was obtained by forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Synthesis Example 13]
Using the hydrophobic unit (1-a) synthesized in Synthesis Example 1, instead of 1.49 g (4.7 mmol) of 2,5-dichloro-4 ′-(1-imidazolyl) benzophenone of Synthesis Example 1, 2,5- Synthesis was performed in the same manner as in Synthesis Example 1 except that 1.62 g (4.7 mmol) of dichloro-4 ′-(pyridine-4-oxy) benzophenone was used, and a polymer of the formula (13-b) was obtained. A film having a thickness of 30 μm was obtained by forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Synthesis Example 14]
Using the hydrophobic unit (4-a) synthesized in Synthesis Example 4, instead of 1.49 g (4.7 mmol) of 2,5-dichloro-4 ′-(1-imidazolyl) benzophenone of Synthesis Example 1, 2,5- Synthesis was performed in the same manner as in Synthesis Example 1 except that 1.62 g (4.7 mmol) of dichloro-4 ′-(pyridine-4-oxy) benzophenone was used, and a polymer of the formula (13-b) was obtained. A film having a thickness of 30 μm was obtained by forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Synthesis Example 15]
Using the hydrophobic unit (6-a) synthesized in Synthesis Example 6, instead of 1.49 g (4.7 mmol) of 2,5-dichloro-4 ′-(1-imidazolyl) benzophenone of Synthesis Example 1, 2,5- Synthesis was performed in the same manner as in Synthesis Example 1 except that 1.62 g (4.7 mmol) of dichloro-4 ′-(pyridine-4-oxy) benzophenone was used, and a polymer of formula (15-b) was obtained. A film having a thickness of 30 μm was obtained by forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Synthesis Example 16]
37.65 g of neopentyl 3- (2,5-dichlorobenzoyl) benzenesulfonate (9
3.9 mmol), 4- (2,5-dichlorobenzoyl) pyridine 1.18 g (4.7 m)
mol), 11.8 g (1.5 of the hydrophobic unit (1-a) obtained in Synthesis Example 1- (1)
Synthesis was performed in the same manner as in Synthesis Example 1 except that (mmol) was used as a raw material, to obtain a polymer of the formula (16-b). A film having a thickness of 30 μm was obtained by forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Synthesis Example 17]
Using the hydrophobic unit (4-a) synthesized in Synthesis Example 4, instead of 1.49 g (4.7 mmol) of 2,5-dichloro-4 ′-(1-imidazolyl) benzophenone in Synthesis Example 16, 4- (2 , 5-dichlorobenzoyl) pyridine was synthesized in the same manner as in Synthesis Example 1 except that 1.18 g (4.7 mmol) was used, to obtain a polymer of the formula (17-b). By forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1, a film thickness of 30
A film of μm was obtained. Table 1 shows the physical properties of the obtained hydrophobic unit, polymer, and film.

[Synthesis Example 18]
Using the hydrophobic unit (6-a) synthesized in Synthesis Example 6, instead of 1.49 g (4.7 mmol) of 2,5-dichloro-4 ′-(1-imidazolyl) benzophenone in Synthesis Example 16, 4- (2 , 5-dichlorobenzoyl) pyridine was synthesized in the same manner as in Synthesis Example 1 except that 1.18 g (4.7 mmol) was used, and a polymer of formula (18-b) was obtained. By forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1, a film thickness of 30
A film of μm was obtained. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Comparative Synthesis Example 1]
30.8 g (192 mmol) of 2,7-dihydroxynaphthalene (2,7-NAP) of Synthesis Example 1 and 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoro Instead of using 96.8 g (288 mmol) of propane (Bis-AF),
The same as Synthesis Example 1 except that 161.4 g (480 mmol) of 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane (Bis-AF) was used. The hydrophobic unit (19-a) was synthesized by the method, and the resulting hydrophobic unit was used for synthesis in the same manner as in Synthesis Example 1 to obtain a polymer of the formula (19-b). A film having a thickness of 30 μm was obtained by forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Comparative Synthesis Example 2]
39.46 g of neopentyl 3- (2,5-dichlorobenzoyl) benzenesulfonate (9
8.3 mmol), 13.3 g (1.7 mmol) of the hydrophobic unit (1-a) obtained in Synthesis Example 1- (1), 2.62 g (4.0 mmol) of bis (triphenylphosphine) nickel dichloride, Sodium iodide 0.45 g (3.0 mmol), triphenylphosphine 1
Synthesis was performed in the same manner as in Synthesis Example 1, except that 0.49 g (40 mmol) and 15.69 g (240 mmol) of zinc were used as raw materials, and a polymer of formula (20-b) was obtained. A film having a thickness of 30 μm was obtained by forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Comparative Synthesis Example 3]
Synthesis was performed in the same manner as in Comparative Synthesis Example 2 except that the hydrophobic unit (19-a) synthesized in Comparative Synthesis Example 1 was used to obtain a polymer of the formula (21-b). A film having a thickness of 30 μm was obtained by forming the obtained polymer from NMP / methanol in the same manner as in Synthesis Example 1. Tables 1 and 2 show the physical properties of the obtained hydrophobic unit, polymer, and film.

[Example 1]
[Preparation of paste A]
Place 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) prepared using the sulfonated polyarylene obtained in Synthesis Example 1, and 1,2-dimethoxyethane 13.97 g was added, and the mixture was stirred for 60 minutes with a wafer blower to obtain paste A having a viscosity of 50 cp (25 ° C.).
[Production of gas diffusion layer]
Carbon black and polytetrafluoroethylene (PTFE) particles are mixed at a weight ratio of carbon black: PTFE particles = 4: 6, and a slurry in which the resulting mixture is uniformly dispersed in ethylene glycol is mixed on one side of carbon paper. The base layer was applied and dried to prepare two diffusion layers 3 composed of the base layer and carbon paper.
[Production of gas diffusion electrode]
On the diffusion layer produced above, paste A was applied using a doctor blade so that the amount of platinum applied was 0.5 mg / cm ² . This was heated and dried at 95 ° C. for 10 minutes to form a gas diffusion electrode layer.
[Production of membrane-electrode assembly]
One electrolyte membrane (thickness 30 μm) prepared in Synthesis Example 1 is prepared, sandwiched between the pair of gas diffusion electrode layers prepared above, and under the condition of 160 ° C. × 15 min under a pressure of 100 kg / cm ^2. The membrane-electrode assembly was prepared by hot press molding.
[Power generation evaluation]
A polymer electrolyte fuel cell was constructed by laminating a separator also serving as a gas flow path on both sides of the membrane-electrode assembly obtained above. Using this as a single cell, one was supplied with air as an oxygen electrode, and the other was supplied with pure hydrogen as a fuel electrode to generate electricity. The power generation conditions were a cell temperature of 95 ° C., an air electrode side relative humidity of 75%, and a fuel electrode side relative humidity of 40%, and the cell voltage was measured at an initial current density of 1 A / cm ² after 500 hours. The results are shown in Table 3.
[Example 2]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 2 was used, and power generation was evaluated. The results are shown in Table 3.
[Example 3]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 3 was used, and power generation was evaluated. The results are shown in Table 3.
[Example 4]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 4 was used, and power generation was evaluated. The results are shown in Table 3.
[Example 5]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 5 was used, and power generation was evaluated. The results are shown in Table 3.
[Example 6]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 6 was used, and power generation was evaluated. The results are shown in Table 3.
[Example 7]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 7 was used, and power generation was evaluated. The results are shown in Table 3.
[Example 8]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 8 was used, and power generation was evaluated. The results are shown in Table 3.
[Example 9]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 9 was used, and power generation was evaluated. The results are shown in Table 3.
[Example 10]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 10 was used, and power generation was evaluated. The results are shown in Table 3.
[Example 11]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 11 was used, and power generation was evaluated. The results are shown in Table 3.
[Example 12]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 12 was used, and power generation was evaluated. The results are shown in Table 3.
[Example 13]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 13 was used, and power generation was evaluated. The results are shown in Table 3.
[Example 14]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 14 was used, and power generation was evaluated. The results are shown in Table 3.
[Example 15]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 15 was used, and power generation was evaluated. The results are shown in Table 3.
[Example 16]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 16 was used, and power generation was evaluated. The results are shown in Table 3.
[Example 17]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 17 was used, and power generation was evaluated. The results are shown in Table 3.
[Example 18]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Synthesis Example 18 was used, and power generation was evaluated. The results are shown in Table 3.
[Comparative Example 1]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Comparative Synthesis Example 1 was used, and power generation was evaluated. The results are shown in Table 3.
[Comparative Example 2]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Comparative Synthesis Example 2 was used, and power generation was evaluated. The results are shown in Table 3.
[Comparative Example 3]
A membrane-electrode assembly was prepared in the same manner as in Example 1 except that the sulfonated polymer prepared in Comparative Synthesis Example 3 was used, and power generation was evaluated. The results are shown in Table 3.
[Power generation evaluation results]
Table 3 shows the power generation evaluation results of Example 1-18 and Comparative Example 1-3. By using the polymer electrolyte excellent in heat resistance and mechanical properties shown in the present invention, any membrane-electrode composite can generate high output at high temperature and has excellent long-term power generation durability. I understood it.

Claims (14)

A condensed aromatic ring unit represented by the formula (1):
A solid polymer fuel cell comprising a polyarylene copolymer having a main chain having a polyphenylene structure and a side chain having a nitrogen-containing heterocyclic group represented by the following formula (A): Electrode electrolyte for use.

Wherein (1), A, D is a direct bond, -O -, - S -, - CO -, - SO 2 -, - SO -, - CONH -, - COO -, - (CF 2) i - (I is an integer of 1 to 10), — (CH ₂ ) _j — (j is an integer of 1 to 10), —CR ′ ₂ — (R ′ is an aliphatic hydrocarbon group, 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, B represents an oxygen atom or a sulfur atom, and Ph represents a condensed aromatic ring. shown, R ₁ to R ₂₀ may be the being the same or different, a hydrogen atom, a fluorine atom, an alkyl group, a part or all of halogenated halogenated alkyl group, an allyl group, an aryl group, At least one atom selected from the group consisting of a nitro group and a nitrile group The other represents a group. l and m represent an integer of 0 to 4, and q represents an integer of 2 or more. t shows the integer of 0-4. n and p indicate the composition ratio of each unit, and p is a value other than 0 among 0 to 1, and n + p = 1.
In the formula (A), Z is a direct bond or at least one selected from the group consisting of —O— and —S—.
Indicates the type of structure, Y _{is, -CO -, - SO 2 -} , - SO -, - CONH -, - COO-,
_{- (CF 2) l '-} (l' is an integer of 1 to _{10), - C (CF 3)} 2 - represents at least one structure selected from the group consisting of, R ₂₁ is a nitrogen-containing heterocyclic A ring group is shown. b shows the integer of 1-5, a shows the integer of 0-4.
Among the single lines at the end of the structural unit, those not having a substituent displayed on one side mean connection with the adjacent structural unit. ]   2. The polymer electrolyte fuel according to claim 1, wherein in the formula (1), Ph is a divalent group consisting of an aromatic ring selected from the group consisting of naphthalene, anthracene, tetracene, and pentacene. Battery electrode electrolyte. 2. The electrode electrolyte for a polymer electrolyte fuel cell according to claim 1, wherein the condensed aromatic ring unit is represented by the following formula (2):

[In the formula (2), A represents a direct bond, —O—, —CO—, —SO ₂ —, —SO—, — (CF ₂ ) _i.
- (i is an integer of 1 to _{10), - (CH 2) j} - (j is an integer of 1 to _{10), - CR '2 - (} R' represents an aliphatic hydrocarbon group, an aromatic hydrocarbon A hydrogen group or 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 ) _j — (j is an integer of 1 to 10) and —CR ′ ₂ — (R ′ is an aliphatic hydrocarbon group, aromatic carbonization. Represents at least one structure selected from the group consisting of a hydrogen group or a halogenated hydrocarbon group),
Ph represents a condensed aromatic ring, R _{1 to} R ₂₀ may be the same 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, At least one atom or group selected from the group consisting of allyl group, aryl group, nitro group and nitrile group is shown.
l represents an integer of 0 to 4, and q represents an integer of 2 or more. t shows the integer of 0-4.
n and p indicate the composition ratio of each unit, and p is a value other than 0 among 0 to 1, and n + p = 1.
Among the single lines at the end of the structural unit, those not having a substituent displayed on one side mean connection with the adjacent structural unit. ] The electrode polymer electrolyte for a polymer electrolyte fuel cell according to claim 3, wherein the condensed aromatic ring unit is represented by the formula (3);

[In the formula (3), D is selected from the group consisting of —O—, —CR ′ ₂ — (R ′ represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group or a halogenated hydrocarbon group). At least one structure is shown.
P is at least one structure selected from structures represented by the following formulas (4-1) to (4-3);
Ph is a structure represented by the following formula (5-1).
q represents an integer of 2 or more. t shows the integer of 0-4.
n and p indicate the composition ratio of each unit, and p is a value other than 0 among 0 to 1, and n + p = 1.
Among the single lines at the end of the structural unit, those not having a substituent displayed on one side mean connection with the adjacent structural unit. ]

In the said Formula (3), p exists in the range of 0.01-1, The polymer electrolyte fuel cell electrode electrolyte of Claim 4 characterized by the above-mentioned. The nitrogen-containing heterocyclic group is pyrrole, thiazole, isothiazole, oxazole, isoxazole, pyridine, imidazole, imidazoline, pyrazole, 1,3,5-triazine, pyrimidine, pyritazine, pyrazine, indole, quinoline, isoquinoline, bromine, benz It is at least one group derived from a compound selected from the group consisting of nitrogen-containing heterocyclic compounds consisting of imidazole, benzoxazole, benzthiazole, tetrazole, tetrazine, triazole, carbazole, acridine, quinoxaline, quinazoline and derivatives thereof. An electrode electrolyte for a polymer electrolyte fuel cell according to any one of claims 1 to 5. 2. The electrode electrolyte for a polymer electrolyte fuel cell according to claim 1, wherein the unit having a nitrogen-containing heterocyclic group in the side chain is a structural unit represented by the following general formula (B).

(In the formula (B), Y, Z, R 21, a, b are of the single lines at the ends of. The structural unit is the same as formula (A), those wherein a substituent does not appear in the one hand adjacent (This means connection with the structural unit.) 8. The polymer electrolyte fuel cell according to claim 1, wherein the polyarylene-based copolymer further includes a side chain having a sulfonic acid group represented by the following general formula (E). Electrode electrolyte.

(In the formula (E), Z is a direct bond or at least one selected from the group consisting of -O- and -S-.
Indicates the type of structure, Y _{is, -CO -, - SO 2 -} , - SO -, - CONH -, - COO-,
_{- (CF 2) l '-} (l' is an integer of 1 to 10), - indicating at least one structure selected from the group consisting of - C (CF _{3) 2.} Ar is an aromatic group having a substituent represented by —SO ₃ H, —O (CH ₂ ) _h SO ₃ H or —O (CF ₂ ) _h SO ₃ H (h represents an integer of 1 to 12). Indicates. c
Represents an integer of 0 to 10, d represents an integer of 0 to 10, and k represents an integer of 1 to 4. ) The polyarylene copolymer according to claim 8, wherein the side chain having a sulfonic acid group is a structural unit represented by the following general formula (F).

(In the formula (F), Y, Z, Ar, c, d, and k are the same as those in the formula (E). Of the single lines at the end of the structural unit, those that do not have a substituent on one side are adjacent. (It means connection with a matching unit.) An electrode varnish comprising the electrode electrolyte for a polymer electrolyte fuel cell according to any one of claims 1 to 9. An electrode paste comprising the electrode electrolyte for a polymer electrolyte fuel cell according to any one of claims 1 to 9 and catalyst particles.   12. The electrode paste according to claim 11, wherein the solvent constituting the paste is a mixed solvent of water and at least one organic solvent, and the mixed solvent is a poor solvent for the proton conductive membrane. A polymer electrolyte fuel cell electrode comprising the polymer electrolyte fuel cell electrode electrolyte according to any one of claims 1 to 9 and catalyst particles.   A membrane-electrode assembly comprising the polymer electrolyte fuel cell electrode according to claim 13 on at least one surface of a polymer electrolyte membrane.