JP2007106986A - Block copolymer and method for producing the same, polymer electrolyte, catalytic composition, polymer electrolyte membrane, membrane/electrode assembly and fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a block copolymer which can give an excellent proton-conductive polymer electrolyte. <P>SOLUTION: The method for producing a block copolymer comprises a step for producing a polymer is which a first polymer compound having an ion-exchanging group and a second polymer compound having substantially no ion-exchanging group are bonded in a mixture solvent of two or more solvents. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a block copolymer and a method for producing the same, a polymer electrolyte, a catalyst composition, a polymer electrolyte membrane, a membrane-electrode assembly, and a fuel cell.

  Conventionally, as a proton conductive polymer electrolyte used for a proton conductive membrane in a solid polymer fuel cell, a perfluoroalkylsulfonic acid polymer is mainly used because of its excellent characteristics as a fuel cell. . However, since this material is very expensive, a material for a polymer electrolyte that can be provided at a lower cost has been actively developed in order to spread a power generation system using a fuel cell more widely.

As a material for a polymer electrolyte replacing the perfluoroalkylsulfonic acid polymer, for example, a material in which a sulfonic acid group is introduced into an aromatic polyether having excellent heat resistance and high film strength has been proposed. For example, a sulfonated polyether ketone system (Patent Document 1) and a sulfonated polyethersulfone system (Patent Documents 2 and 3) are disclosed. In addition, a block copolymer comprising a segment into which an ion exchange group is introduced and a segment into which no ion exchange group is introduced is known as a material capable of forming a polymer electrolyte exhibiting excellent proton conductivity (patent) References 4, 5).
Japanese National Patent Publication No. 11-502249 Japanese Patent Laid-Open No. 10-45913 Japanese Patent Laid-Open No. 10-21944 JP 2001-250567 A Japanese Patent Laid-Open No. 2003-3232

  In recent years, solid polymer fuel cells are expected to be put to practical use as generators for residential and automotive applications. For such fuel cells, operation with higher efficiency than before is expected. Is required to be possible. In order to increase the efficiency of the fuel cell, it is effective to increase the proton conductivity of the polymer electrolyte used for the proton conducting membrane, and even higher proton conductivity than the above-mentioned conventional polymer electrolyte materials. There is a need for improvement.

  Then, this invention is made | formed in view of such a situation, and it aims at providing the method of manufacturing the block copolymer which can comprise the polymer electrolyte which has the outstanding proton conductivity. The present invention also provides a block copolymer obtained from such a production method, a polymer electrolyte and a polymer electrolyte membrane containing the block copolymer, a catalyst composition containing the polymer electrolyte, and a polymer electrolyte membrane or a catalyst layer. And a fuel cell including the membrane-electrode assembly.

  In order to achieve the above-mentioned object, the present inventors have conducted intensive research. As a result, in the block copolymer constituting the polymer electrolyte, a segment into which an ion-exchange group has been introduced, and an ion-exchange group have been introduced. It was found that a block copolymer capable of exhibiting excellent proton conductivity can be obtained by increasing the molecular weight of each segment that is not present.

  Usually, a block copolymer can be synthesized by block copolymerization of a polymer compound for forming each segment, but in order to increase the molecular weight of the segment as described above, each segment is formed. It is necessary to use a polymer compound having a higher molecular weight than the conventional polymer compound. However, according to the study results of the present inventors, the polymer compound for forming each segment becomes difficult to dissolve in a single solvent due to the increase in the molecular weight as described above. Therefore, it has been found that there is a tendency that only one of the polymer compounds is likely to be precipitated in the solvent. For this reason, when the molecular weight of each segment is increased, block copolymerization does not proceed sufficiently, and there are many cases in which a good block copolymer cannot be obtained.

  Therefore, as a result of further investigation by the present inventors, it is possible to use a polymer compound having a high molecular weight as described above by using a combination of a plurality of solvents as a solvent used for block copolymerization. The inventors have found that block copolymerization can be carried out, and have completed the present invention.

  That is, the method for producing a block copolymer of the present invention includes a first polymer compound having an ion exchange group in a mixed solvent containing two or more solvents, and a second substantially free of an ion exchange group. It has the process of obtaining the polymer which couple | bonded with the high molecular compound.

  As described above, in the production method of the present invention, since a mixed solvent containing two or more solvents is used, any single solvent can be used as the polymer compound for forming each segment of the block copolymer. Even in the case of using a combination that causes precipitation, these can be dissolved satisfactorily, and the block copolymerization reaction of these polymer compounds can be performed satisfactorily. . As a result, a block copolymer in which a segment having an ion exchange group introduced therein and a segment having no ion exchange group introduced therein are respectively increased in molecular weight can be obtained, thereby having excellent proton conductivity. A polymer electrolyte is obtained.

  The mixed solvent preferably contains a good solvent for the first polymer compound. Thereby, dissolution of the first polymer compound in the mixed solvent becomes advantageous, and block copolymerization proceeds more favorably. The mixed solvent more preferably contains a good solvent for the second polymer. By doing so, the second polymer compound is also well dissolved in the mixed solvent, and a block copolymer in which each segment has a high molecular weight can be reliably obtained.

  More specifically, the mixed solvent preferably contains 20% by mass or more of the good solvent for the first polymer compound. Further, it is more preferable that the good solvent for the second polymer compound is contained in an amount of 20% by mass or more. In this way, the first and / or second polymer compound is more satisfactorily dissolved in the mixed solvent, and the production of block copolymer in which each segment has a high molecular weight is further advantageous.

  Here, the “good solvent for the first (or second) polymer compound” refers to a solvent that can dissolve the polymer compound in 100 g at 25 ° C. to a concentration of 5% by mass or more. And In addition, when multiple types of 1st (or 2nd) high molecular compounds are contained, the total amount (g) of those dissolutions is used as a reference. The term “dissolved” as used herein means a state where the polymer compound and the solvent form a uniform liquid phase.

  The ion exchange group possessed by the first polymer compound is preferably a cation exchange group. Thereby, the obtained block copolymer comes to have a segment containing a cation exchange group. Such a block copolymer can exhibit excellent proton conductivity when used as a polymer electrolyte. Especially, as a cation exchange group, a sulfonic acid group is preferable.

  In the present invention, at least one of the first and second polymer compounds is preferably an aromatic polymer compound. In particular, it is more preferable that both the first and second polymer compounds are aromatic polymer compounds. If it carries out like this, it will become easy to obtain the polymer electrolyte which has the more excellent heat resistance and gas barrier property. In the present specification, the “aromatic polymer compound” refers to a compound in which 50% or more of the repeating units mainly constituting the compound have an aromatic ring in the main chain. To do.

  Furthermore, the first polymer compound preferably has a molecular weight of 2000 or more. Also, the second polymer compound preferably has a molecular weight of 2000 or more. If it carries out like this, each segment in the obtained block copolymer will become what became high molecular weight, and also it will become possible to obtain the polymer electrolyte which is excellent in proton conductivity.

  In the production method of the present invention, the relative permittivity of the good solvent of the first polymer compound is 40.0 or more, and the relative permittivity of the good solvent of the second polymer compound is less than 40.0. It is preferable. In this way, both the first and second polymer compounds are dissolved well in the mixed solvent, and as a result, a block copolymer in which each segment has a high molecular weight can be obtained favorably. In this case, if the difference between the relative permittivity of the good solvent of the first polymer compound and the relative permittivity of the good solvent of the second polymer compound is 5.0 or more, This is preferable because dissolution in a mixed solvent is further improved.

  More specifically, the good solvent for the first polymer compound is preferably dimethyl sulfoxide (DMSO). In this case, particularly when the first polymer compound has the above-described cation exchange group, particularly a sulfonic acid group, dissolution of the compound in a mixed solvent is advantageous. The good solvent for the second polymer compound is more preferably N-methylpyrrolidone. If it carries out like this, a 2nd high molecular compound will melt | dissolve more favorably in a mixed solvent.

［式中、Ａｒ^７１は、炭素数１〜２０のアルキル基、炭素数１〜２０のアルコキシ基、炭素数６〜２０のアリール基、炭素数６〜２０のアリールオキシ基又は炭素数２〜２０のアシル基を有していてもよい２価の芳香族基を示し、Ｘ^７１は、直接結合、酸素原子、硫黄原子、カルボニル基又はスルホニル基を示し、ｄは５以上の整数である。］ Specifically, the first polymer compound described above is preferably a compound having a structure represented by the following general formula (7) and having an ion exchange group in the structure.

[In the formula, Ar ⁷¹ represents an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, or 2 to 20 carbon atoms. A divalent aromatic group optionally having an acyl group, X ⁷¹ represents a direct bond, an oxygen atom, a sulfur atom, a carbonyl group or a sulfonyl group, and d is an integer of 5 or more. ]

［式中、Ａｒ^１１、Ａｒ^１２、Ａｒ^１３、Ａｒ^１４、Ａｒ^１５、Ａｒ^１６及びＡｒ^１７（以下、「Ａｒ^１１〜Ａｒ^１７」のように表記する）は、それぞれ独立に、炭素数１〜２０のアルキル基、炭素数１〜２０のアルコキシ基、炭素数６〜２０のアリール基、炭素数６〜２０のアリールオキシ基又は炭素数２〜２０のアシル基を有していてもよい２価の芳香族基を示し、Ｘ^１１〜Ｘ^１５は、それぞれ独立に、酸素原子又は硫黄原子を示し、Ｙ^１１及びＹ^１２は、それぞれ独立に、カルボニル基又はスルホニル基を示し、ｐ、ｑ及びｒは、それぞれ独立に、５以上の整数である。］ More specifically, the first polymer compound is a compound having a structure represented by the following general formula (1a), (1b) or (1c) and having an ion exchange group in this structure. More preferably.

[In the formula, Ar ¹¹ , Ar ¹² , Ar ¹³ , Ar ¹⁴ , Ar ¹⁵ , Ar ¹⁶ and Ar ¹⁷ (hereinafter referred to as “Ar ^{11 to} Ar ¹⁷ ”) are each independently represented by 1 to Divalent which may have 20 alkyl groups, C1-C20 alkoxy groups, C6-C20 aryl groups, C6-C20 aryloxy groups, or C2-C20 acyl groups X ^{11 to} X ¹⁵ each independently represents an oxygen atom or a sulfur atom, Y ¹¹ and Y ¹² each independently represent a carbonyl group or a sulfonyl group, and p, q and r Are each independently an integer of 5 or more. ]

［式中、Ｙ^２１は、カルボニル基又はスルホニル基を示し、ｓ及びｔは、それぞれ独立に０又は１であって少なくともいずれか一方が１であり、ｕは０、１又は２であり、ｖは１又は２であり、ｗは５以上の整数である。］ More specifically, the first polymer compound is more preferably a compound having a structure represented by the following general formula (2).

[Wherein Y ²¹ represents a carbonyl group or a sulfonyl group, s and t are each independently 0 or 1, at least one of which is 1, u is 0, 1 or 2; Is 1 or 2, and w is an integer of 5 or more. ]

［式中、Ｘ^１７１は、直接結合又は有機基であり、ｆは１からＸ^１７１における置換可能な部位の数までの整数であり、ｇは１又は２であり、ｌは５以上の整数である。］ Furthermore, the first polymer compound is more preferably a compound having a structure represented by the following general formula (17).

[ ^Wherein X ¹⁷¹ is a direct bond or an organic group, f is an integer from 1 to the number of substitutable sites in X ¹⁷¹ , g is 1 or 2, and l is an integer of 5 or more. is there. ]

［式中、Ａｒ^３１は、炭素数１〜２０のアルキル基、炭素数１〜２０のアルコキシ基、炭素数６〜２０のアリール基、炭素数６〜２０のアリールオキシ基又は炭素数２〜２０のアシル基を有していてもよい２価の芳香族基を示し、Ｘ^３１は、直接結合、酸素原子、硫黄原子、カルボニル基又はスルホニル基を示し、ｚは５以上の整数である。］ On the other hand, the second polymer compound is preferably a compound having a structure represented by the following general formula (3).

[In the formula, Ar ³¹ represents an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, or 2 to 20 carbon atoms. And X ³¹ represents a direct bond, an oxygen atom, a sulfur atom, a carbonyl group or a sulfonyl group, and z is an integer of 5 or more. ]

［式中、Ａｒ^４１、Ａｒ^４２及びＡｒ^４３は、それぞれ独立に、炭素数１〜２０のアルキル基、炭素数１〜２０のアルコキシ基、炭素数６〜２０のアリール基、炭素数６〜２０のアリールオキシ基又は炭素数２〜２０のアシル基を有していてもよい２価の芳香族基を示し、Ｘ^４１及びＸ^４２は、それぞれ独立に、酸素原子又は硫黄原子を示し、Ｚ^４１は、カルボニル基又はスルホニル基を示し、ｈは５以上の整数である。］ Such a second polymer compound may be a compound having a structure represented by the following general formula (4).

[Wherein, Ar ⁴¹ , Ar ⁴² and Ar ⁴³ each independently represent an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or 6 to 20 carbon atoms. An aryloxy group or a divalent aromatic group optionally having an acyl group having 2 to 20 carbon atoms, X ⁴¹ and X ⁴² each independently represent an oxygen atom or a sulfur atom, and Z ⁴¹ Represents a carbonyl group or a sulfonyl group, and h is an integer of 5 or more. ]

［式中、Ａｒ^５１は、炭素数１〜２０のアルキル基、炭素数１〜２０のアルコキシ基、炭素数６〜２０のアリール基、炭素数６〜２０のアリールオキシ基又は炭素数２〜２０のアシル基を有していてもよい２価の芳香族基を示し、Ｘ^５１及びＸ^５２は、それぞれ独立に、酸素原子又は硫黄原子を示し、Ｒ^５１及びＲ^５２は、それぞれ独立に、炭素数１〜２０のアルキル基、炭素数１〜２０のアルコキシ基、炭素数６〜２０のアリール基、炭素数６〜２０のアリールオキシ基又は炭素数２〜２０のアシル基を示し、Ｚ^５１は、カルボニル基又はスルホニル基を示し、ｊ及びｋは、それぞれ独立に、０〜４の整数であり、ｉは、５以上の整数である。］ More specifically, the second polymer compound is preferably a compound having a structure represented by the following general formula (5).

[In the formula, Ar ⁵¹ represents an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, or 2 to 20 carbon atoms. A divalent aromatic group optionally having an acyl group, X ⁵¹ and X ⁵² each independently represents an oxygen atom or a sulfur atom, and R ⁵¹ and R ⁵² each independently represent a carbon atom. C 1 -C 20 alkyl group, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryl group or an acyl group having 2 to 20 carbon atoms having from 6 to 20 carbon ^{atoms, Z 51} is , A carbonyl group or a sulfonyl group, j and k are each independently an integer of 0 to 4, and i is an integer of 5 or more. ]

  The present invention also provides a block copolymer obtainable by the production method of the present invention. As described above, such a block copolymer has a segment having an ion exchange group having a higher molecular weight than the conventional one and a segment having substantially no ion exchange group. A conductive polymer electrolyte can be formed.

  Such a block copolymer of the present invention preferably has an ion exchange capacity of 0.1 to 4 meq / g. A block copolymer having such an ion exchange capacity can form a polymer electrolyte having further excellent proton conductivity. By containing these block copolymers of the present invention as proton conducting components, the polymer electrolyte of the present invention is constituted.

  The present invention further provides a catalyst composition containing the polymer electrolyte of the present invention and a catalyst. Such a catalyst composition is suitable as a constituent material of the catalyst layer disposed adjacent to the proton conducting membrane in the membrane-electrode assembly constituting the fuel cell.

  The present invention also provides a polymer electrolyte membrane comprising the polymer electrolyte of the present invention. Since such a polymer electrolyte membrane has excellent proton conductivity, a fuel cell using such a polymer electrolyte as a proton conducting membrane is extremely efficient.

  The present invention also provides a membrane-electrode assembly that uses the polymer electrolyte of the present invention and is applied to a fuel cell. That is, the membrane-electrode assembly of the present invention includes a polymer electrolyte membrane and a catalyst layer formed on the polymer electrolyte membrane, and the polymer electrolyte membrane contains the polymer electrolyte of the present invention. It is characterized by that. A fuel cell including such a membrane-electrode assembly can generate power with high efficiency.

  Furthermore, the present invention provides a membrane-electrode assembly using the polymer electrolyte of the present invention as a catalyst layer. That is, the membrane-electrode assembly of the present invention comprises a polymer electrolyte membrane and a catalyst layer formed on the polymer electrolyte membrane, and the catalyst layer contains the polymer electrolyte and catalyst of the present invention. It is characterized by that. In such a membrane-electrode assembly, the catalyst layer can also exhibit high proton conductivity. For this reason, a fuel cell provided with this membrane-electrode assembly becomes extremely efficient.

  Furthermore, the present invention provides a fuel cell comprising the membrane-electrode assembly of the present invention. That is, the fuel cell of the present invention includes a pair of separators and a membrane-electrode assembly disposed between the pair of separators, and the membrane-electrode assembly is the membrane-electrode assembly of the present invention. It is characterized by. Since such a fuel cell includes the membrane-electrode assembly of the present invention, it can be operated with extremely high efficiency.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the block copolymer which is a material for polymer electrolytes which can form the proton conductive film | membrane which has the outstanding proton conductivity. Further, a polymer electrolyte and a polymer electrolyte membrane including such a proton copolymer and having high proton conductivity, a membrane-electrode assembly including the same, and a high-efficiency operation including the membrane-electrode assembly It is possible to provide a fuel cell capable of performing the above.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings as necessary.
[Method for producing block copolymer]

  First, the manufacturing method of the block copolymer which concerns on suitable embodiment is demonstrated. In this embodiment, a block copolymer having a segment having an ion exchange group and a segment having substantially no ion exchange group is produced. Here, the “segment” refers to a polymer structural unit formed by connecting a plurality of predetermined repeating units in a block copolymer. The “block copolymer” refers to a polymer compound in which two or more types of segments are bonded directly or via a linking group.

  In this embodiment, when preferred, the segment having an ion exchange group in the block copolymer is composed of a polymer compound having an ion exchange group (first polymer compound), and the ion exchange group is substantially The segment which does not have is comprised from the high molecular compound (2nd high molecular compound) which does not have an ion exchange group substantially. That is, the block copolymer is constituted by a polymer in which a first polymer compound and a second polymer compound are bonded. And in this embodiment, the said polymer is synthesize | combined in the mixed solvent containing 2 or more types of solvents. In addition, the high molecular compound in this specification means the compound containing two or more predetermined repeating units, and includes both an oligomer and a polymer.

(First polymer compound)
First, the first polymer compound will be described. As the ion exchange group possessed by the first polymer compound, either a cation exchange group or an anion exchange group can be applied. These ion exchange groups partially or entirely form a salt with a counter ion. It may be.

［式中、Ｘ^６１及びＸ^６２は、それぞれ独立に−Ｏ−、−Ｓ−又は−ＮＲ−を表し、Ｚ^６１は−ＣＯ−、−Ｃ（Ｓ）−、−Ｃ（ＮＲ^６３）−、置換基を有していてもよいアルキレン基又は置換基を有していてもよいアリーレン基を表す。また、上記ＮＲ^６３におけるＲ^６３は、水素原子、置換基を有していてもよい炭素数１〜６のアルキル基又は置換基を有していてもよい炭素数６〜１０のアリール基を表す。ａは、繰り返しの数を表わし、ａ＝０〜１０の整数を表わす。なお、ａ個のＺ^６１はそれぞれ同一であってもよく、異なっていてもよい。） Examples of such ion-exchange groups, for _{example, -SO 3 H, -COOH, -PO} (OH) 2, -POH (OH), - SO 2 NHSO 2 -, - Ph a _{(OH) (Ph} represents a phenyl group A cation exchange group such as a group represented by the following general formula (6) (a group having such a structure is hereinafter referred to as an “oxocarbon group”), —NH ₂ , —NHR, —NRR ′, —NRR ′ Anion exchange groups such as R ″ ⁺ , —NH ₃ ^{+ and the} like (R, R ′ and R ″ each independently represents an alkyl group, a cycloalkyl group or an aryl group) and the like can be mentioned.

[Wherein, X ⁶¹ and X ⁶² each independently represent —O—, —S— or —NR—, and Z ⁶¹ represents —CO—, —C (S) —, —C (NR ⁶³ ) —, It represents an alkylene group which may have a substituent or an arylene group which may have a substituent. Further, R ⁶³ in the above NR ⁶³ represents a hydrogen atom, 1 to 6 carbon atoms which may have a substituent alkyl or optionally substituted aryl group having 6 to 10 carbon atoms . a represents the number of repetitions, and a represents an integer of 0 to 10. The a Z ⁶¹ may be the same or different. )

Among them, the ion exchange group is preferably a cation exchange group, more preferably —SO ₃ H, —PO (OH) ₂ , —POH (OH), —SO ₂ NHSO ₂ — or an oxocarbon group. ₃ H, —PO (OH) ₂ or an oxocarbon group is more preferable, and —SO ₃ H is particularly preferable.

  In the first polymer compound, the ion exchange group is preferably contained in an average of 0.5 or more per repeating unit constituting the polymer compound, and is contained in 0.8 or more. It is more preferable that 1.0 or more are included. When the content of ion exchange groups is less than 0.5 per repeating unit, the amount of ion exchange groups in the segment comprising the first polymer compound becomes insufficient, and the proton conductivity of the block copolymer. Tend to be insufficient.

  The first polymer compound is preferably an aromatic polymer compound, such as polyphenylene, polyphenylene ether, polyphenylene sulfide, polyether ketone, polyether sulfone, or a copolymer of repeating units constituting them, In the repeating unit, a compound in which an ion exchange group is introduced so as to satisfy the above-mentioned condition can be mentioned. In the aromatic polymer compound as the first polymer compound, the bonding position of the ion exchange group is not particularly limited, but it is bonded to the aromatic ring (particularly the benzene ring) in the repeating unit from the viewpoint of ease of synthesis and the like. It is preferable.

［式中、Ａｒ^７１は、炭素数１〜２０のアルキル基、炭素数１〜２０のアルコキシ基、炭素数６〜２０のアリール基、炭素数６〜２０のアリールオキシ基又は炭素数２〜２０のアシル基を有していてもよい２価の芳香族基を示し、Ｘ^７１は、直接結合、酸素原子、硫黄原子、カルボニル基又はスルホニル基を示し、ｄは５以上の整数である。］ More specifically, the first polymer compound has a structure represented by the following general formula (7), and an ion exchange group as described above is introduced into at least a part of the repeating unit. Compounds.

[In the formula, Ar ⁷¹ represents an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, or 2 to 20 carbon atoms. A divalent aromatic group optionally having an acyl group, X ⁷¹ represents a direct bond, an oxygen atom, a sulfur atom, a carbonyl group or a sulfonyl group, and d is an integer of 5 or more. ]

  The molecular weight of the first polymer compound is preferably 2000 or more, more preferably 4000 or more, still more preferably 6000 or more, still more preferably 8000 or more, and particularly preferably 10,000 or more. preferable. When the molecular weight of the first polymer compound is 2000 or more, the proton conductivity of the polymer electrolyte containing the resulting block copolymer is good. In addition, the value of this molecular weight can be calculated | required by the analysis by a gel permeation chromatography (GPC), for example.

  For example, when the first polymer compound is synthesized by polycondensation (for example, polycondensation of a dihalogeno monomer and a diol monomer), the molecular weight of the first polymer compound is a ratio of the substance amounts of these monomers. It is possible to control by adjusting the ratio, and when synthesizing by chain polymerization, it can be controlled by adjusting the ratio of the amount of the initiator to the monomer.

［式中、Ａｒ^１１〜Ａｒ^１７は、それぞれ独立に、炭素数１〜２０のアルキル基、炭素数１〜２０のアルコキシ基、炭素数６〜２０のアリール基、炭素数６〜２０のアリールオキシ基又は炭素数２〜２０のアシル基を有していてもよい２価の芳香族基を示し、Ｘ^１１〜Ｘ^１５は、それぞれ独立に、酸素原子又は硫黄原子を示し、Ｙ^１１及びＹ^１２は、それぞれ独立に、カルボニル基又はスルホニル基を示し、ｐ、ｑ及びｒは、それぞれ独立に、５以上の整数である。］ Specifically, such a first polymer compound has a structure represented by the following general formula (1a), (1b) or (1c), and an ion exchange group is present in the structure. The compound which has is mentioned.

[In the formula, Ar ^{11 to} Ar ¹⁷ are each independently an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aryloxy having 6 to 20 carbon atoms. A divalent aromatic group optionally having a C 2-20 acyl group, X ^{11 to} X ¹⁵ each independently represents an oxygen atom or a sulfur atom, and Y ¹¹ and Y ¹² Each independently represents a carbonyl group or a sulfonyl group, and p, q, and r are each independently an integer of 5 or more. ]

In the above formulas (1a), (1b) and (1c), p, q and r are each independently preferably an integer of 5 to 250, more preferably an integer of 10 to 200, and 15 to 150. More preferably, it is an integer. Further, the terminal structure of the first polymer compound having these structures depends on the raw material monomer used when the compound is synthesized, and examples thereof include a hydroxy group. In the structures represented by the above formulas (1a), (1b), and (1c), groups represented by Ar ^{11 to} Ar ¹⁷ , X ^{11 to} X ¹⁵ , and Y ^{11 to} Y ¹² are each a repeating unit. The same group may be different from each other. However, from the viewpoint of ease of synthesis, etc., these are preferably the same for each repeating unit.

In the above formulas (1a), (1b) and (1c), examples of the group represented by Ar ^{11 to} Ar ¹⁷ include bivalent monocyclic carbonization such as 1,3-phenylene and 1,4-phenylene. Hydrogen aromatic group, 1,3-naphthalenediyl, 1,4-naphthalenediyl, 1,5-naphthalenediyl, 1,6-naphthalenediyl, 1,7-naphthalenediyl, 2,6-naphthalenediyl, 2,7 -Divalent condensed hydrocarbon aromatic groups such as naphthalenediyl, 3,3'-biphenylylene, 3,4'-biphenylylene, 4,4'-biphenylylene, diphenylmethane-4 ', 4'-diyl, 2,2 -Divalent polycyclic rings such as diphenylpropane-4 ′, 4 ″ -diyl, 1,1,1,3,3,3-hexafluoro-2,2-diphenylpropane-4 ′, 4 ″ -diyl Hydrocarbon aromatic group, pyridine Yl, quinoxalinediyl, heterocyclic aromatic groups such as thiophenediyl. Of these, divalent hydrocarbon aromatic groups are preferred.

  Moreover, as above-mentioned, these groups are a C1-C20 alkyl group, a C1-C20 alkoxy group, a C6-C20 aryl group, a C6-C20 aryloxy group, or carbon number. It may be substituted with 2 to 20 acyl groups. Here, examples of the alkyl group having 1 to 20 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an allyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, and an isobutyl group. Alkyl groups having 1 to 20 carbon atoms such as n-pentyl group, 2,2-dimethylpropyl group, cyclopentyl group, n-hexyl group, cyclohexyl group, 2-methylpentyl group, 2-ethylhexyl group, and the like. Substituents are substituted with halogen atoms such as fluorine atom, chlorine atom, bromine atom, hydroxyl group, nitrile group, amino group, methoxy group, ethoxy group, isopropyloxy group, phenyl group, phenoxy group, etc. Examples include alkyl groups having 1 to 20 carbon atoms.

  Examples of the alkoxy group having 1 to 20 carbon atoms include methoxy group, ethoxy group, n-propyloxy group, isopropyloxy group, n-butyloxy group, sec-butyloxy group, tert-butyloxy group, isobutyloxy group, and n-pentyl. An alkoxy group having 1 to 20 carbon atoms such as oxy group, 2,2-dimethylpropyloxy group, cyclopentyloxy group, n-hexyloxy group, cyclohexyloxy group, 2-methylpentyloxy group, 2-ethylhexyloxy group, These alkoxy groups are substituted with halogen atoms such as fluorine atom, chlorine atom, bromine atom, hydroxyl group, nitrile group, amino group, methoxy group, ethoxy group, isopropyloxy group, phenyl group, phenoxy group, etc. An alkoxy group containing 1 to 20 carbon atoms It is below.

  Examples of the aryl group having 6 to 20 carbon atoms include an aryl group having 6 to 20 carbon atoms such as a phenyl group and a naphthyl group, a halogen atom such as a fluorine atom, a chlorine atom and a bromine atom, and a hydroxyl group. A group, a nitrile group, an amino group, a methoxy group, an ethoxy group, an isopropyloxy group, a phenyl group, a phenoxy group, and the like, and an aryl group having 1 to 20 carbon atoms including the substituent.

  Moreover, as an aryloxy group having 6 to 20 carbon atoms, for example, an aryloxy group having 6 to 20 carbon atoms such as a phenoxy group and a naphthyloxy group, a fluorine atom, a chlorine atom, a bromine atom, etc. Substituted with a halogen atom, a hydroxyl group, a nitrile group, an amino group, a methoxy group, an ethoxy group, an isopropyloxy group, a phenyl group, a phenoxy group, etc. Groups and the like.

  Furthermore, examples of the acyl group having 2 to 20 carbon atoms include an acyl group having 2 to 20 carbon atoms such as an acetyl group, a propionyl group, a butyryl group, an isobutyryl group, a benzoyl group, a 1-naphthoyl group, and a 2-naphthoyl group. In these groups, fluorine atoms, chlorine atoms, halogen atoms such as bromine atoms, hydroxyl groups, nitrile groups, amino groups, methoxy groups, ethoxy groups, isopropyloxy groups, phenyl groups, naphthyl groups, phenoxy groups, naphthyloxy groups, etc. And an acyl group having 2 to 20 carbon atoms in total including this substituent.

Examples of such a first polymer compound include compounds having the following structure. That is, as the structure represented by the general formula (1a), for example, a structure represented by the following formulas 8-1 to 8-7 is preferable. In the following formula, n is preferably an integer of 10 or more, more preferably an integer of 10 to 250, and still more preferably an integer of 15 to 150. n ′ is preferably an integer of 5 or more, more preferably an integer of 5 to 250, still more preferably an integer of 10 to 200, and particularly preferably an integer of 15 to 150. In the formula, a sulfonic acid group is exemplified as the ion exchange group, but an ion exchange group other than the sulfonic acid group may be used.

Moreover, as a structure represented by the said general formula (1b), the structure represented by following formula 9-1 to 9-15 is preferable. N 'in a formula is synonymous with the above. In the formula, a sulfonic acid group is shown as the ion exchange group, but an ion exchange group other than the sulfonic acid group may be used.

［式中、Ｙ^２１は、カルボニル基又はスルホニル基を示し、ｓ及びｔは、それぞれ独立に０又は１であって少なくともいずれか一方は１であり、ｕは０、１又は２であり、ｖは１又は２であり、ｗは５以上の整数である。］ Among the structures described above, the structure represented by the general formula (1b) is preferably a structure represented by the following general formula (2). Such a structure includes the structures represented by 9-1 to 4, 9-13, and 9-14.

[Wherein Y ²¹ represents a carbonyl group or a sulfonyl group, s and t are each independently 0 or 1, at least one is 1, u is 0, 1 or 2; Is 1 or 2, and w is an integer of 5 or more. ]

Furthermore, examples of the structure represented by the general formula (1c) include structures represented by the following formulas 10-1 to 10-10. N and n 'in a formula are synonymous with the above. In the formula, a sulfonic acid group is shown as the ion exchange group, but an ion exchange group other than the sulfonic acid group may be used.

［式中、Ｘ^１７１は、直接結合又は有機基であり、ｆは１からＸ^１７１における置換可能な部位の数までの整数であり、ｇは１又は２であり、ｌは５以上の整数である。ｇが２である場合、２つのＸ^１７１、ｆ及びｇは、それぞれ同一であっても、異なっていてもよい。］ Furthermore, as the first polymer compound, those having a structure represented by the following general formula (17) are also suitable.

[ ^Wherein X ¹⁷¹ is a direct bond or an organic group, f is an integer from 1 to the number of substitutable sites in X ¹⁷¹ , g is 1 or 2, and l is an integer of 5 or more. is there. When g is 2, two X ¹⁷¹ , f and g may be the same or different. ]

When the group represented by X ¹⁷¹ is an organic group, X ¹⁷¹ is an organic group to which f sulfonic acid groups are bonded, and may further have a substituent other than the sulfonic acid group. Examples of the organic group include an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 1 to 20 carbon atoms, and an acyl having 2 to 20 carbon atoms. Groups. Examples of the group that may be substituted with these organic groups include halogen atoms such as fluorine atom, chlorine atom, bromine atom, hydroxyl group, nitrile group, amino group, methoxy group, ethoxy group, isopropyloxy group, and phenyl group. And a phenoxy group. In the above formula, when g is 2, two X ^171s may be the same or different.

The organic group represented by X ¹⁷¹ is preferably a group containing one or more aromatic rings. In this case, the sulfonic acid group bonded to X ¹⁷¹ in formula (17) is preferably bonded directly to the aromatic ring contained in X ¹⁷¹ or via a predetermined group, and X ¹⁷¹ has an aromatic ring. When there are a plurality of them, they may be bonded to a plurality of these aromatic rings. Examples of the aromatic ring include a benzene ring and a condensed ring (such as a naphthalene ring).

［式中、Ｘ^１８１及びＸ^１８２はそれぞれ独立に直接結合、酸素原子又はカルボニル基であり、Ａｒ^１８１及びＡｒ^１８２はそれぞれ独立に芳香環であり、Ｑは、スルホン酸基を含む基であり、ｅは０〜３の整数であり、ｙ及びｙ’はそれぞれ独立に０〜３の整数であってそれらの合計が１以上となる数である。なお、ｌ及びｇは上記と同義である。ただし、ｅが２以上である場合、複数のＸ^１８１及びＡｒ^１８１は、それぞれ同じであっても異なっていてもよい。 When the group represented by X ¹⁷¹ is an organic group containing an aromatic ring, the structure represented by the general formula (17) is preferably a structure represented by the following general formula (18a).

^Wherein X ¹⁸¹ and X ¹⁸² are each independently a direct bond, an oxygen atom or a carbonyl group, Ar ¹⁸¹ and Ar ¹⁸² are each independently an aromatic ring, and Q is a group containing a sulfonic acid group, e is an integer of 0 to 3, and y and y ′ are each independently an integer of 0 to 3, and the sum thereof is 1 or more. Here, l and g are as defined above. However, when e is 2 or more, the plurality of X ¹⁸¹ and Ar ¹⁸¹ may be the same or different.

［式中、ｌは上記と同義である。］ Moreover, as a high molecular compound represented by the said General formula (17), what has a structure where ^X171 in General formula (17) is a direct bond is preferable. Such a structure is specifically represented by the following general formula (18b).

[Wherein l is as defined above. ]

式（１９ｅ）及び（１９ｆ）中、Ｘ^１９は酸素原子、硫黄原子、カルボニル基又はスルホニル基であり、ｂ及びｂ´はそれぞれ独立に０〜１２の整数である。］ Specific examples of Q that is a group containing a sulfonic acid group in the general formula (18a) include groups represented by the following (19a) to (19f).

In the formulas (19e) and (19f), X ¹⁹ is an oxygen atom, a sulfur atom, a carbonyl group or a sulfonyl group, and b and b ′ are each independently an integer of 0 to 12. ]

Specific examples of the structural unit constituting the compound having the structure represented by the general formula (17) include compounds represented by the following formulas 20-1 to 20-11. In the following formula, Q, y, and y ′ are as defined above, and y and y ′ are preferably 1 to 3, respectively. y ″ is an integer of 0-2.

  Among the above structures constituting the first polymer compound, the structure represented by the general formula (2) is preferable, and among them, the above formulas 9-1, 9-2, 9-13, or 9-14 The structure represented is more preferable, the structure represented by the formula 9-13 or 9-14 is more preferable, and the structure represented by the formula 9-13 is particularly preferable.

(Second polymer compound)
Next, the second polymer compound will be described. The second polymer compound is a polymer compound that does not substantially contain an ion exchange group. Here, “substantially free of ion exchange groups” means that most of the repeating units mainly constituting the second polymer compound have no ion exchange groups, specifically, The average number of ion-exchange groups per repeating unit constituting the polymer compound is 0.1 or less, preferably 0.05 or less, and has an ion-exchange group in the repeating unit. More preferably not.

  The second polymer compound is preferably an aromatic polymer compound, such as polyphenylene, polyphenylene ether, polyphenylene sulfide, polyether ketone, polyether sulfone, or a copolymer of repeating units constituting these, The compound which does not contain an exchange group substantially is mentioned.

  The molecular weight of the second polymer compound is preferably 2000 or more, more preferably 4000 or more, further preferably 6000 or more, still more preferably 8000 or more, and particularly preferably 10,000 or more. preferable. When the molecular weight of the second polymer compound is 2000 or more, the proton conductivity of the polymer electrolyte containing the resulting block copolymer is good. The molecular weight value can be determined in the same manner as in the first polymer compound.

［式中、Ａｒ^３１は、炭素数１〜２０のアルキル基、炭素数１〜２０のアルコキシ基、炭素数６〜２０のアリール基、炭素数６〜２０のアリールオキシ基又は炭素数２〜２０のアシル基を有していてもよい２価の芳香族基を示し、Ｘ^３１は、直接結合、酸素原子、硫黄原子、カルボニル基又はスルホニル基を示し、ｚは５以上の整数である。］ More specifically, examples of the second polymer compound include compounds having a structure represented by the following general formula (3). The second polymer compound does not substantially have an ion exchange group as described above. If the second polymer compound satisfies the above definition, one ion exchange group is not included in the structure of the following formula (3). You may have in a part. The same applies to the various second polymer compounds exemplified below.

[In the formula, Ar ³¹ represents an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, or 2 to 20 carbon atoms. And X ³¹ represents a direct bond, an oxygen atom, a sulfur atom, a carbonyl group or a sulfonyl group, and z is an integer of 5 or more. ]

［式中、Ａｒ^４１、Ａｒ^４２及びＡｒ^４３は、それぞれ独立に、炭素数１〜２０のアルキル基、炭素数１〜２０のアルコキシ基、炭素数６〜２０のアリール基、炭素数６〜２０のアリールオキシ基又は炭素数２〜２０のアシル基を有していてもよい２価の芳香族基を示し、Ｘ^４１及びＸ^４２は、それぞれ独立に、酸素原子又は硫黄原子を示し、Ｚ^４１は、カルボニル基又はスルホニル基を示し、ｈは５以上の整数である。］ As such a second polymer compound, a compound having a structure represented by the following general formula (4) is suitable.

[Wherein, Ar ⁴¹ , Ar ⁴² and Ar ⁴³ each independently represent an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or 6 to 20 carbon atoms. An aryloxy group or a divalent aromatic group optionally having an acyl group having 2 to 20 carbon atoms, X ⁴¹ and X ⁴² each independently represent an oxygen atom or a sulfur atom, and Z ⁴¹ Represents a carbonyl group or a sulfonyl group, and h is an integer of 5 or more. ]

In the compound represented by the general formula (4), examples of the group represented by Ar ^{41 to} Ar ⁴³ include the same groups as the groups represented by Ar ^{11 to} Ar ¹⁷ , and among them, a phenylene group Is preferred. X ⁴¹ and X ⁴² are preferably an oxy group (—O—). Furthermore, h is preferably an integer of 10 to 500. In the structure represented by the above formula (4), the groups represented by Ar ^{41 to} Ar ⁴³ , X ⁴¹ and X ⁴² or Z ⁴¹ may be different for each repeating unit or may be the same. Good.

［式中、Ａｒ^５１は、炭素数１〜２０のアルキル基、炭素数１〜２０のアルコキシ基、炭素数６〜２０のアリール基、炭素数６〜２０のアリールオキシ基又は炭素数２〜２０のアシル基を有していてもよい２価の芳香族基を示し、Ｘ^５１及びＸ^５２は、それぞれ独立に、酸素原子又は硫黄原子を示し、Ｒ^５１及びＲ^５２は、それぞれ独立に、炭素数１〜２０のアルキル基、炭素数１〜２０のアルコキシ基、炭素数６〜２０のアリール基、炭素数６〜２０のアリールオキシ基又は炭素数２〜２０のアシル基を示し、Ｚ^５１は、カルボニル基又はスルホニル基を示し、ｊ及びｋは、それぞれ独立に、０〜４の整数であり、ｉは、５以上の整数である。］ As the structure constituting the second polymer compound, a structure represented by the following general formula (5) is particularly preferable.

[In the formula, Ar ⁵¹ represents an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, or 2 to 20 carbon atoms. A divalent aromatic group optionally having an acyl group, X ⁵¹ and X ⁵² each independently represents an oxygen atom or a sulfur atom, and R ⁵¹ and R ⁵² each independently represent a carbon atom. C 1 -C 20 alkyl group, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryl group or an acyl group having 2 to 20 carbon atoms having from 6 to 20 carbon ^{atoms, Z 51} is , A carbonyl group or a sulfonyl group, j and k are each independently an integer of 0 to 4, and i is an integer of 5 or more. ]

In the formula, each of Ar ⁵¹ , X ⁵¹ , X ⁵² and Z ⁵¹ is preferably the same group as Ar ⁴³ , X ⁴¹ , X ⁴² and Z ^41, and Ar ⁵¹ is preferably a phenylene group or a biphenylene group. Is preferred. Moreover, i is preferably an integer of 5 to 500. Furthermore, as R ⁵¹ or R ⁵² , a functional group such as a group that may be substituted with Ar ^{11 to} Ar ¹⁷ described above may be mentioned. The j and k are particularly preferably 0.

Examples of such second polymer compound include polyether ether ketone which may have a substituent when Z ⁴¹ (Z ⁵¹ ) is a carbonyl group (—CO—), and Z ^{When 41} (Z ⁵¹ ) is a sulfonyl group (—SO ₂ —), examples thereof include polyether ether sulfone which may have a substituent. When both are included, poly which may have a substituent Examples include ether ether ketone ether ether sulfone.

More specifically, the second polymer compound preferably has, for example, a structure represented by the following formulas 11-1 to 11-18. In the following formula, m has the same meaning as h or i.

  Especially, as a structure which comprises a 2nd high molecular compound, at least 1 sort (s) of the structure represented by said Formula 11-1-10 and 11-15-18 is preferable, and said Formula 11-1, 3 is preferable. , 11-5 to 7 and 11-15 to 18 are more preferable, and a structure represented by Formula 11-1 or 11-15 is more preferable, and Formula 11-15 is used. The structure represented by is particularly preferable.

(Mixed solvent)
Next, the mixed solvent will be described. As described above, the mixed solvent is a solvent in which two or more solvents are mixed, and examples thereof include a combination of two or more solvents having different relative dielectric constants. In particular, the mixed solvent includes a good solvent for the first polymer compound (hereinafter referred to as “first good solvent”) and a good solvent for the second polymer compound (hereinafter referred to as “second good solvent”). ) Including at least one type is preferable, and including both of these is more preferable. When a plurality of types of the first polymer compound or the second polymer compound are used, a plurality of types may be used in combination as the first and second good solvents.

  For example, when the first good solvent is contained in the mixed solvent, the content of the good solvent is preferably 10% by mass or more, more preferably 20% by mass or more in the mixed solvent, 30 More preferably, it is more preferably 40% by mass or more. When the second good solvent is contained, the content of the good solvent in the mixed solvent is preferably 10% by mass or more, more preferably 20% by mass or more, and 30% by mass or more. More preferably, it is more preferably 40% by mass or more. Even in the case where both of these are included, it is more preferable that both of the solvents satisfy the above conditions. When the content of the first or second good solvent in the mixed solvent is less than 10% by mass, any of the polymer compounds is hardly dissolved in the mixed solvent, and precipitates during block copolymerization. It tends to be difficult to obtain a block copolymer.

  The concentration of the first and second polymer compounds in the mixed solvent during block copolymerization, that is, 100 × [{weight of the first polymer compound (g)} + {second polymer compound The weight (g)}] / [weight (g) of block copolymer solution] is preferably 1 to 50% by mass, more preferably 3 to 40% by mass, and 5 to 30% by mass. % Is more preferable, and 7 to 20% by mass is particularly preferable. By doing so, the first and second polymer compounds are sufficiently dissolved in the mixed solvent even during the block copolymerization, and the block copolymer proceeds well.

  The first good solvent includes a solvent having a relative dielectric constant of preferably 40.0 or more. The second good solvent includes a solvent having a relative dielectric constant of preferably less than 40.0. In order to dissolve both the first and second polymer compounds satisfactorily, the difference in relative dielectric constant between them is preferably 5.0 or more. According to the mixed solvent in which the first and second good solvents satisfying the relative dielectric constant are combined, the first and second polymer compounds are sufficiently dissolved, and the block copolymerization proceeds well. It becomes like this.

  More specifically, examples of the first good solvent include alcohol solvents, ether solvents, sulfoxide solvents, amide solvents, carbonates, oligoalkylene glycols, and fluorine substituents introduced into these solvents. And the like. These solvents are preferably used as appropriate according to the type of the first polymer compound, in particular, the type of ion exchange group possessed by the compound.

  Examples of alcohol solvents include methanol, ethanol, isopropanol, butanol and the like. Examples of ether solvents include diethyl ether, dibutyl ether, diphenyl ether, tetrahydrofuran (THF), dioxane, dioxolane, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, and the like.

  Examples of the sulfoxide solvent include dimethyl sulfoxide (DMSO). Examples of the amide solvent include N, N-dimethylacetamide (DMAc), N-methylacetamide, N, N-dimethylformamide (DMF), N-methylformamide, formamide, N-methylpyrrolidone (NMP) and the like.

  Carbonic acid esters include propylene carbonate, ethylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, 4-trifluoromethyl-1,3-dioxolan-2-one, 1,2-di (methoxycarbonyloxy) ethane and the like. Esters include methyl formate, methyl acetate, and γ-butyrolactone, nitriles include acetonitrile and butyronitrile, and oligoalkylene glycols include oligo (ethylene glycol), oligo (propylene glycol), and oligo (butylene glycol). Etc.

  Among the above, the first good solvent is preferably an alcohol solvent, a sulfoxide solvent or an amide solvent, more preferably a sulfoxide solvent or an amide solvent, still more preferably a sulfoxide solvent, and particularly preferably DMSO. DMSO is particularly preferable because the compound can be dissolved well when the first polymer compound has a sulfonic acid group as an ion exchange group.

  As the second good solvent, ketone solvents, ether solvents, halogen solvents, sulfoxide solvents, sulfone solvents, amide solvents, carbonates, esters, nitriles, oligoalkylene glycols, Examples thereof include a solvent obtained by introducing a fluorine substituent.

  Examples of the ketone solvent include acetone, methyl isobutyl ketone, methyl ethyl ketone, and benzophenone. Examples of ether solvents include diethyl ether, dibutyl ether, diphenyl ether, tetrahydrofuran (THF), dioxane, dioxolane, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, and the like.

  Examples of the halogen-based solvent include chloroform, dichloromethane, 1,2-dichloroethane, 1,1,2,2-tetrachloroethane, chlorobenzene, dichlorobenzene, and the like, and examples of the sulfoxide-based solvent include DMSO. Examples of the sulfone solvent include diphenyl sulfone and sulfolane, and examples of the amide solvent include DMAc, N-methylacetamide, DMF, N-methylformamide, formamide, and NMP.

  Carbonic acid esters include propylene carbonate, ethylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, 4-trifluoromethyl-1,3-dioxolan-2-one, 1,2-di (methoxycarbonyloxy) ethane and the like. Esters include methyl formate, methyl acetate, and γ-butyrolactone, nitriles include acetonitrile and butyronitrile, and oligoalkylene glycols include oligo (ethylene glycol), oligo (propylene glycol), and oligo (butylene glycol). Etc.

  Among the above-described solvents, the second good solvent is preferably a ketone solvent, a sulfoxide solvent, a sulfone solvent or an amide solvent, more preferably a sulfoxide solvent or an amide solvent, still more preferably an amide solvent, and NMP. Particularly preferred.

  The first good solvent and the second good solvent may have the same kind of structure as long as each is a good solvent for the first and second polymer compounds. Are used in combination with solvents having different characteristics among those having the same kind of structure. Specifically, as described above, the amide solvent is a good solvent for both the first and second polymer compounds. For example, when DMAc is used as the first good solvent, the second good solvent is used. A solvent other than DMAc, such as DMF or NMP, is selected as the solvent.

  A preferred combination of the first good solvent and the second good solvent is preferably a combination in which the first good solvent is a sulfoxide solvent and the second good solvent is an amide solvent. A combination in which the first good solvent is DMSO and the second good solvent is NMP is particularly preferable.

  As the mixed solvent, in addition to the first good solvent and the second good solvent described above, other solvents may be further added as long as the solubility of the first and second polymer compounds in the mixed solvent is not lowered. You may contain. Examples of such other solvents include aromatic hydrocarbon solvents such as benzene, toluene, and xylene for azeotropic dehydration, and halogenated aromatic hydrocarbon solvents such as chlorobenzene and dichlorobenzene.

(Block copolymerization)
In the present embodiment, a block copolymer is obtained by synthesizing a polymer composed of a first polymer compound and a second polymer compound in the above-described mixed solvent. In this case, the polymerization reaction may be carried out in a mixed solvent from the beginning, or may be carried out by adding another type of solvent in the middle after starting in a single solvent. However, in order to homogenize the molecular weight distribution of the obtained block copolymer, it is preferable to use a mixed solvent from the start of the reaction.

As a more suitable block copolymerization method, for example, the following method (A), (B) or (C) can be mentioned. That is,
(A) After synthesizing one of the first polymer compound and the second polymer compound in a mixed solvent, the one polymer compound obtained in the mixed solvent Block copolymerization of the polymer with other polymer compounds to obtain a block copolymer,
(B) Synthesizing one of the first polymer compound and the second polymer compound in a mixed solvent, and causing the other polymer compound to coexist. Then, while synthesizing the one polymer compound, the block copolymer of this and the other polymer compound is simultaneously advanced to obtain a block copolymer,
(C) A reaction solution obtained by synthesizing the first polymer compound in a single solvent and a reaction solution obtained by synthesizing the second polymer compound in another single solvent were mixed and mixed. And a method in which a block copolymer is obtained by block copolymerization of a first polymer compound and a second polymer compound in a solution.

  In the method (A), the block copolymerization of the first polymer compound and the second polymer compound is carried out by (A-1) a condensation reaction between the first polymer compound and the second polymer compound, (A-2) The first polymer compound and the second polymer compound can be produced by a method of bonding via a compound that functions as a linking group.

  Examples of the method (A-1) include the following. That is, first, one of the polymer compound having a hydroxyl group at the terminal and the polymer compound having a halogeno group at the terminal is used as the first polymer compound and the other is used as the second polymer compound. And nucleophilic substitution condensation in the presence of a base catalyst.

  Further, as the first and second polymer compounds, polymer compounds having a hydroxyl group at one end and a halogeno group at the other end are used, respectively, and these are nucleophilically substituted in the presence of a base catalyst. The method of condensing to is also mentioned. Furthermore, a method of using a compound having a halogeno group at the terminal as the first and second polymer compounds and bonding them by a dehalogenation condensation reaction is also included.

  On the other hand, as the method (A-2), a polymer compound having a hydroxyl group at the terminal is used as each of the first and second polymer compounds, and these are used as 4,4′-difluorobenzophenone, decafluorobiphenyl, Examples thereof include a method of bonding via a compound capable of forming a linking group by causing a condensation reaction with the above-described both polymer compounds, such as hexafluorobenzene and 4,4′-difluorodiphenylsulfone. Moreover, the polymer compound which has a halogeno group at the terminal is used as the first and second polymer compounds, respectively, and these are used as 4,4′-dihydroxybiphenyl, bisphenol A, 4,4′-dihydroxybenzophenone, 4, 4 Examples of the method include bonding with a compound capable of forming a linking group by causing a condensation reaction with the above-described both polymer compounds, such as' -dihydroxydiphenylsulfone.

  In the method (A), after synthesizing the first polymer compound in a mixed solvent, this and the second polymer compound are bonded together by the method described above. For example, it can be carried out by a method of polymerizing monomers and / or polymer compounds capable of causing the same condensation reaction as described above. In this case, as a method of introducing an ion exchange group into the first polymer compound, a method of adding an ion exchange group to the polymer obtained by the above polymerization, a monomer or a polymer before the formation of this polymer, Both methods using compounds having an ion exchange group can be applied.

  As a method for introducing a sulfonic acid group into the structure represented by the general formula (1a), (1b) or (1c) by the former method, for example, the general formula (1a), (1b) or (1c Or a compound having a structure represented by) is dissolved or suspended in concentrated sulfuric acid or fuming sulfuric acid, or at least partially dissolved in an organic solvent, and then concentrated sulfuric acid, chlorosulfuric acid, fuming sulfuric acid or The method of making sulfur trioxide etc. act can be illustrated.

  In addition, when the first and second polymer compounds are bonded via a linking group as in the method (A-2), a compound having three or more functional groups, for example, When a polyfunctional compound such as decafluorobiphenyl or hexafluorobenzene is used, a block copolymer having a branched structure can be synthesized by appropriately controlling the reaction conditions. In this case, by changing the charged composition of the first polymer compound and the second polymer compound, a linear block copolymer and a branched block copolymer can be produced separately.

  On the other hand, in the method (B), the synthesis of any one of the first polymer compound and the second polymer compound is performed by, for example, using a monomer having a condensable functional group as a base catalyst. It can be carried out by condensation in the presence of nucleophilic substitution and polymerizing the monomers. Examples of such condensation include those described above in (A-1), and examples of the condensable functional group include a hydroxyl group or a halogeno group. In the case of synthesizing the first polymer compound in such polymerization, it is preferable to use a monomer having an ion exchange group.

  In addition, any one of the first and second polymer compounds coexisting during the synthesis includes a functional group capable of condensing with the condensable functional group of the above-described monomer. Those having a group (hydroxyl group or halogeno group) are mentioned. As a result, the polymer compound and the monomer under synthesis are combined by a condensation reaction. As a result, simultaneously with the synthesis of one polymer compound, block copolymerization of the polymer compound with the other polymer compound proceeds.

  More specifically, examples of the method (B) include the following methods. That is, (B-1) nucleophilic substitution of a monomer having two halogeno groups and a monomer having two hydroxyl groups in the presence of one polymer compound having a hydroxyl group at the terminal is carried out under a base catalyst. A method of synthesizing the other polymer compound to synthesize the other polymer compound. (B-2) In the presence of one polymer compound having a hydroxyl group at the terminal, monomers having both a halogeno group and a hydroxyl group are condensed with each other in a nucleophilic substitution manner under a base catalyst, A method of synthesizing the above polymer compound is also included.

  Further, (B-3) in the presence of one polymer compound having a halogeno group at the terminal, a monomer having two halogeno groups and a monomer having two hydroxyl groups are nucleophilically substituted under a base catalyst. A method of synthesizing the other polymer compound by condensation is also exemplified. Furthermore, in the presence of one polymer compound having a halogeno group at the terminal (B-4), monomers having both a halogeno group and a hydroxyl group are condensed in a nucleophilic substitution manner under a base catalyst, A method of synthesizing the other polymer compound is also included.

  In the method (C), the first polymer compound and the second polymer compound are separately synthesized in different solvents, and then mixed to react with each other. Block copolymerization of the first polymer compound and the second polymer compound is performed. As the form of such block copolymerization, (C-1) the condensation reaction of the first polymer compound and the first polymer compound, and (C-2) the same as in the method (A) above, Examples include a method in which a polymer compound of 1 and a second polymer compound are bonded via a compound that functions as a linking group, except that a single solvent is used during the synthesis of each polymer compound. It can be carried out in the same manner as in the method A).

(Block copolymer)
As described above, by reacting the first polymer compound and the second polymer compound in a mixed solvent, a segment having an ion exchange group and a segment having substantially no ion exchange group are obtained. The block copolymer which has is obtained.

  As such a block copolymer, for example, a segment having the structure represented by the general formula (1a), (1b) or (1c) having a structure having an ion exchange group in the structure; What has the segment which has a structure represented by the said General formula (3) can be illustrated.

And as a specific example of such a block copolymer, what is represented by following formula 12-1 to 12-12 can be illustrated, for example. In addition, description of "block" in a following formula represents having at least one segment derived from the first polymer compound and one segment derived from the second polymer compound. That is, the block copolymer represented by the following formula is not limited to one having only one of both the above segments.

  Among the block copolymers obtained by the present embodiment, compounds represented by 12-2, 12-8, and 12-9 to 12-12 are preferable, and represented by 12-9 to 12-12. The compound represented by 12-9 or 12-10 is more preferred, and the compound represented by 12-10 is particularly preferred.

  The mass composition ratio between the segment having an ion exchange group and the segment having substantially no ion exchange group in such a block copolymer is not particularly limited, but is 3:97 to 70 in terms of mass%. : 30, preferably 5:95 to 60:40, more preferably 10:90 to 50:50, and particularly preferably 20:80 to 40:60. When the composition ratio of the segment having an ion exchange group is in the above range, the resulting polymer electrolyte membrane using the block copolymer is preferable because it has excellent proton conductivity and good water resistance. Such a block copolymer particularly suitably functions as a polymer electrolyte membrane for fuel cells.

  In addition, the amount of ion exchange groups introduced as a whole block copolymer is preferably 0.1 mmol to 4 mmol per 1 g of the block copolymer. That is, the ion exchange capacity of the block copolymer is preferably 0.1 meq / g to 4.0 meq / g. From the viewpoint of obtaining better proton conductivity, the ion exchange capacity of the block copolymer is more preferably 0.8 meq / g to 3.0 meq / g, and further preferably 1.3 meq / g to 2.5 meq / g. preferable. If the ion exchange capacity of the block copolymer is less than 0.1 meq / g, proton conductivity may be low, and the function as a polymer electrolyte for a fuel cell may be insufficient. On the other hand, if it exceeds 4 meq / g, the water resistance tends to decrease. The amount of such ion exchange groups introduced is the content of the ion exchange groups in the first polymer compound and the molecular weight of the first polymer compound (number average molecular weight) during the production of the block copolymer. Alternatively, it can be controlled by adjusting the blending ratio of the first polymer compound and the second polymer compound.

  Furthermore, the molecular weight of the block copolymer obtained in the present embodiment is preferably 5000 to 1000000, and more preferably 15000 to 200000. As such molecular weight, a polystyrene-equivalent number average molecular weight measured by gel permeation chromatography (GPC) can be applied.

  Among these, the average molecular weight of the segment having an ion-exchange group is preferably 2000 or more, more preferably 4000 or more, further preferably 6000 or more, and more preferably 8000 or more in terms of the number average molecular weight in terms of polystyrene. More preferably, it is more preferably 10,000 or more. In addition, this upper limit is preferably 100,000, and more preferably 50,000. Further, the average molecular weight of the segment having substantially no ion exchange group is the above-mentioned polystyrene-equivalent number average molecular weight, preferably 2000 or more, more preferably 4000 or more, still more preferably 6000 or more, and 8000. More preferably, it is more preferably 10,000 or more. The upper limit is preferably 200,000, and more preferably 100,000.

  As described above, the block copolymer obtained in this embodiment has a segment having an ion exchange group and a segment having substantially no ion exchange group. Each of which may be a block copolymer, may be a block copolymer having two or more of any one segment, and may be any of a multi-block copolymer having two or more of both segments. Also good.

Further, the block copolymer may further have a segment other than the two segments described above. For example, the number of ion-exchange groups per repeating unit is more than 0.1 on average. It may have a segment larger than 0.5. Such a segment can be introduced into the block copolymer by adding, as a raw material, a polymer compound that satisfies the condition of the ion exchange group at the time of block copolymerization.
[Fuel cell]

  Next, a fuel cell using a polymer electrolyte containing a block copolymer obtained by the production method of the present invention will be described.

  FIG. 1 is a diagram schematically showing a cross-sectional configuration of a fuel cell according to a preferred embodiment. As shown in FIG. 1, the fuel cell 10 has a catalyst layer 14a, 14b, gas diffusion layers 16a, 16b, and separators 18a, 18b in order on both sides of a polymer electrolyte membrane 12 (proton conducting membrane). Is formed. A membrane-electrode assembly (hereinafter abbreviated as “MEA”) 20 is composed of the polymer electrolyte membrane 12 and a pair of catalyst layers 14 a and 14 b sandwiching the polymer electrolyte membrane 12.

  The polymer electrolyte membrane 12 is composed of a polymer electrolyte containing a block copolymer obtained by the production method of the above embodiment. Such a polymer electrolyte is mainly composed of a block copolymer which is a proton conducting component.

  Such a polymer electrolyte membrane 12 can be obtained by processing the polymer electrolyte into a film. Examples of processing methods include a method of forming a polymer electrolyte in a solution state (solution casting method), etc. Is mentioned. Specifically, the polymer electrolyte can be dissolved in a suitable solvent, and the resulting solution can be cast on a glass plate, and then the solvent can be removed to form a film.

  The solvent used for film formation is not particularly limited as long as it can dissolve the polymer electrolyte and can be removed after film formation. N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), aprotic polar solvents such as dimethyl sulfoxide (DMSO), chlorinated solvents such as dichloromethane, chloroform, 1,2-dichloroethane, chlorobenzene and dichlorobenzene, methanol , Alcohols such as ethanol and propanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, alkylene glycol monoalkyl ether such as propylene glycol monoethyl ether, tetrahydrofuran, 1, - dioxolane, 1,4-dioxane, 1,3-dioxane, tetrahydropyran, dibutyl ether, tert- butyl methyl ether, diphenyl ether, ether solvents such as crown ethers are preferred. These may be used alone or as a mixture of two or more as required.

  Of these, dimethyl sulfoxide, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, tetrahydrofuran, 1,3-dioxolane and the like are used as membrane-forming solvents for the solubility of the polymer electrolyte. Is preferable.

  Although there is no restriction | limiting in particular in the thickness of the film which comprises the polymer electrolyte membrane 12, It is preferable in it being 10-300 micrometers, and it is more preferable in it being 20-100 micrometers. If the thickness is less than 10 μm, the practical strength as the polymer electrolyte membrane 12 may not be sufficiently obtained. If the thickness is more than 300 μm, the membrane resistance tends to increase and the characteristics of the fuel cell 10 tend to deteriorate. It is in. This film thickness can be controlled by the concentration of the solution and the coating thickness on the substrate.

  The polymer electrolyte constituting the polymer electrolyte membrane 12 contains a plasticizer, a stabilizer, a release agent, etc. used for ordinary polymers as necessary in addition to the block copolymer described above. Also good. Moreover, in the use of a fuel cell, inorganic or organic fine particles may be added as a water retention agent in order to facilitate the water content management. Further, the polymer electrolyte membrane 12 may be a composite alloy of the block copolymer and another polymer by mixed co-casting or the like. Components other than these block copolymers can be used as long as the properties (proton conductivity, etc.) of the polymer electrolyte membrane 12 are not deteriorated.

  The polymer electrolyte membrane 12 may be further cross-linked by irradiating with an electron beam, radiation or the like for the purpose of improving mechanical strength after the film formation. In addition to the polymer electrolyte membrane 12 as described above, the polymer electrolyte membrane 12 is a mixture of a porous film or sheet impregnated with a polymer electrolyte, or a fiber or pulp mixed. It may be reinforced by doing.

  The catalyst layers 14a and 14b adjacent to the polymer electrolyte membrane 12 are layers that function as electrode layers in the fuel cell, and either one of them serves as an anode catalyst layer and the other serves as a cathode catalyst layer. The catalyst layers 14a and 14b are preferably formed from a catalyst composition containing the polymer electrolyte and a catalyst.

  The catalyst is not particularly limited as long as it can activate a redox reaction with hydrogen or oxygen, and examples thereof include noble metals, noble metal alloys, metal complexes, and fired metal complex products obtained by firing metal complexes. . Of these, platinum fine particles are preferable as the catalyst, and the catalyst layers 14a and 14b may be formed by supporting fine particles of platinum on particulate or fibrous carbon such as activated carbon or graphite.

  The gas diffusion layers 16a and 16b are provided so as to sandwich both sides of the MEA 20, and promote the diffusion of the raw material gas into the catalyst layers 14a and 14b. The gas diffusion layers 16a and 16b are preferably composed of a porous material having electronic conductivity. For example, a porous carbon nonwoven fabric or carbon paper efficiently feeds a source gas to the catalyst layers 14a and 14b. It is preferable because it can be transported.

  These polymer electrolyte membrane 12, catalyst layers 14a and 14b, and gas diffusion layers 16a and 16b constitute a membrane-electrode-gas diffusion electrode assembly (MEGA). Such MEGA can be manufactured by the method shown below, for example. That is, first, a solution containing a polymer electrolyte and a catalyst are mixed to form a catalyst composition slurry. This is applied on a carbon non-woven fabric or carbon paper for forming the gas diffusion layers 16a and 16b, and the solvent or the like is evaporated to obtain a laminate in which the catalyst layer is formed on the gas diffusion layer. And while arrange | positioning so that each catalyst layer may oppose a pair of obtained laminated body, the polymer electrolyte membrane 12 is arrange | positioned among these, and these are crimped | bonded. Thus, MEGA having the above-described structure is obtained.

  A method for forming a catalyst layer on a carbon non-woven fabric or carbon paper, and a method for bonding it to a polymer electrolyte membrane are described in, for example, J. Pat. Electrochem. Soc. : Methods described in Electrochemical Science and Technology, 1988, 135 (9), 2209 can be applied.

  Separator 18a, 18b is formed with the material which has electronic conductivity, As this material, carbon, resin mold carbon, titanium, stainless steel etc. are mentioned, for example.

  The fuel cell 10 can be obtained by sandwiching MEGA as described above between a pair of separators 18a and 18b and joining them together.

  The fuel cell of the present invention is not necessarily limited to the above-described configuration, and may have a different configuration as long as it does not depart from the spirit of the fuel cell. For example, in the fuel cell 10, the polymer electrolyte containing the block copolymer obtained by the production method of the present invention was included in both the polymer electrolyte membrane 12 and the catalyst layers 14a and 14b. It is not limited to this, and it may be contained in either one of these. However, from the viewpoint of obtaining a highly efficient fuel cell, it is preferable to be included in both of them. The fuel cell 10 may be one having the above-described structure sealed with a gas seal body or the like.

EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, this invention is not limited to these Examples.
[Synthesis of 4,4′-difluorodiphenylsulfone-3,3′-disulfonate dipotassium]

  First, dipotassium 4,4'-difluorodiphenylsulfone-3,3'-disulfonate used in the synthesis described below was synthesized as shown below. That is, first, 467 g of 4,4′-difluorodiphenylsulfone and 3500 g of 30% fuming sulfuric acid were added to a reactor equipped with a stirrer, and reacted at 100 ° C. for 5 hours. The obtained reaction mixture was cooled and then added to a large amount of ice water, and 470 mL of a 50% aqueous potassium hydroxide solution was further added dropwise thereto.

  Next, the precipitated solid was collected by filtration, washed with ethanol, and dried. The obtained solid was dissolved in 6.0 L of deionized water, 50% aqueous potassium hydroxide solution was added to adjust the pH to 7.5, and then 460 g of potassium chloride was added. The precipitated solid was collected by filtration, washed with ethanol, and dried.

Thereafter, the obtained solid was dissolved in 2.9 L of DMSO, insoluble inorganic salts were removed by filtration, and the residue was further washed with 300 mL of DMSO. To the obtained filtrate, 6.0 L of a solution of ethyl acetate / ethanol = 24/1 was added dropwise, and the precipitated solid was washed with methanol, dried at 100 ° C., and 4,4′-difluorodiphenylsulfone-3,3. 482 g of dipotassium dipotassium disulfonate was obtained.
[Reference test: Comparison of solubility between the first polymer compound and the second polymer compound]

(Reference Example 1)
In a flask equipped with an azeotropic distillation apparatus, 81.69 g of dipotassium 4,4′-difluorodiphenylsulfone-3,3′-disulfonate, potassium 2,5-dihydroxybenzenesulfonate (Samsung Chemical Co., Ltd.) under an argon atmosphere. 31.26 g, 493 g of dimethyl sulfoxide (DMSO) and 77 g of toluene were added, and argon gas was bubbled for 1 hour while stirring them at room temperature.

Thereafter, 19.91 g of potassium carbonate was added to the obtained mixture, and azeotropic dehydration was performed by heating and stirring at 140 ° C. Thereafter, heating was continued while distilling off toluene to obtain a DMSO solution of a polymer compound. Total heating time was 14 hours. A part of the obtained solution is sampled, poured into methanol to precipitate a polymer compound, and further purified by repeated washing with methanol, followed by drying to obtain a repeating unit represented by the following formula (13). The high molecular compound (A) which has was obtained. This polymer compound (A) had a number average molecular weight (Mn) of 9.0 × 10 ³ and a weight average molecular weight (Mw) of 1.7 × 10 ⁴ .

  The obtained polymer compound (A) (first polymer compound) having an ion exchange group was dissolved in an amount of 2.0 g or more in 10 g of DMSO at 25 ° C., but was hardly dissolved in NMP. .

(Reference Example 2)
A flask equipped with an azeotropic distillation apparatus was charged with 76.12 g of 4,4′-difluorodiphenylsulfone, 51.62 g of 2,6-dihydroxynaphthalene, 557 g of N-methylpyrrolidone (NMP), and 94 g of toluene under an argon atmosphere. In addition, argon gas was bubbled for 1 hour while stirring at room temperature.

Thereafter, 49.02 g of potassium carbonate was added to the obtained mixture, and azeotropic dehydration was performed by heating and stirring at 140 ° C. Thereafter, heating was continued while toluene was distilled off. Total heating time was 5 hours. The resulting solution was allowed to cool at room temperature to obtain an NMP solution of a polymer compound. This solution is poured into methanol to precipitate a polymer compound, which is further purified by washing with methanol and then dried to obtain a polymer compound (B) having a repeating unit represented by the following formula (14). It was. This polymer compound (B) had Mn of 2.0 × 10 ⁴ and Mw of 3.8 × 10 ⁴ .

  The obtained polymer compound (B) having no ion exchange group (second polymer compound) was dissolved in an amount of 2.0 g or more in 10 g of NMP at 25 ° C., but hardly dissolved in DMSO. It was. In addition, 2.0 g or more of this polymer compound (B) was dissolved in a mixed solvent composed of 5 g of NMP and 5 g of DMSO.

From the results of the above reference test, the polymer compound (A) having an ion exchange group and the polymer compound (B) having no ion exchange group can be dissolved in a mixed solvent composed of DMSO and NMP. It was confirmed.
[Example 1]

(Synthesis of the first polymer compound)
In a flask equipped with an azeotropic distillation apparatus, under an argon atmosphere, 313.37 g of dipotassium 4,4′-difluorodiphenylsulfone-3,3′-disulfonate, 120.05 g of potassium 2,5-dihydroxybenzenesulfonate, 1892 g of DMSO, And 297 g of toluene was added, and argon gas was bubbled for 1 hour, stirring these at room temperature.

Thereafter, 76.55 g of potassium carbonate was added to the obtained mixture, and azeotropic dehydration was performed by heating and stirring at 140 ° C. Thereafter, heating was continued while distilling off toluene to obtain a DMSO solution of the first polymer compound. Total heating time was 14 hours. The resulting solution was allowed to cool at room temperature. This first polymer compound had Mn of 9.0 × 10 ³ and Mw of 1.8 × 10 ⁴ .

(Synthesis of second polymer compound)
To a flask equipped with an azeotropic distillation apparatus, 250.40 g of 4,4′-difluorodiphenylsulfone, 177.78 g of 2,6-dihydroxynaphthalene, 953 g of DMSO, 953 g of NMP, and 310 g of toluene were added under an argon atmosphere at room temperature. While stirring, argon gas was bubbled for 1 hour.

Thereafter, 169.81 g of potassium carbonate was added to the obtained mixture, and the mixture was stirred at 140 ° C. for azeotropic dehydration. Thereafter, heating was continued while toluene was distilled off. Total heating time was 5 hours. The resulting solution was allowed to cool at room temperature to obtain an NMP / DMSO mixed solution of the second polymer compound. The Mn of this second polymer compound was 1.7 × 10 ⁴ and the Mw was 3.0 × 10 ⁴ .

(Synthesis of block copolymer)
While stirring the resulting NMP / DMSO mixed solution of the second polymer compound, the total amount of the DMSO solution of the first polymer compound and NMP1035 g were added thereto, and block copolymerization reaction was performed at 150 ° C. for 40 hours. Went.

  The obtained reaction solution was dropped into a large amount of 2N hydrochloric acid and immersed for 1 hour. Thereafter, the produced precipitate was filtered off and then immersed again in 2N hydrochloric acid for 1 hour. The obtained precipitate was filtered and washed with water, and then immersed in a large amount of hot water at 95 ° C. for 1 hour. And after filtering off from hot water, it dried at 80 degreeC overnight and the block copolymer was obtained. Table 1 shows the solvent composition during the block copolymerization reaction.

(Production of polymer electrolyte membrane)
The obtained block copolymer was made into an NMP solution of about 20% by weight and developed on a glass plate, and then the solvent was dried at 80 ° C. After drying, the film formed on the glass plate was immersed in a 2N hydrochloric acid aqueous solution, then washed with deionized water until the washing water became neutral, dried, and then the polymer of Example 1 having a thickness of 33 μm. An electrolyte membrane was obtained. This polymer electrolyte membrane had Mn of 8.6 × 10 ⁴ and Mw of 23.4 × 10 ⁴ .
[Example 2]

(Synthesis of the first polymer compound)
In a flask equipped with an azeotropic distillation apparatus, under an argon atmosphere, 313.37 g of dipotassium 4,4′-difluorodiphenylsulfone-3,3′-disulfonate, 120.05 g of potassium 2,5-dihydroxybenzenesulfonate, 1892 g of DMSO, Then, 297 g of toluene was added, and argon gas was bubbled for 1 hour while stirring at room temperature. Thereafter, 76.55 g of potassium carbonate was added and subjected to azeotropic dehydration by heating and stirring at 140 ° C. Thereafter, heating was continued while distilling off toluene to obtain a DMSO solution of the first polymer compound. Total heating time was 14 hours. The resulting solution was allowed to cool at room temperature. The obtained first polymer compound had Mn of 9.0 × 10 ³ and Mw of 1.8 × 10 ⁴ .

(Synthesis of second polymer compound)
In a flask equipped with an azeotropic distillation apparatus, 292.34 g of 4,4′-difluorodiphenylsulfone, 198.21 g of 2,6-dihydroxynaphthalene, 1070 g of DMSO, 1070 g of NMP, and 348 g of toluene are added under an argon atmosphere at room temperature While stirring, argon gas was bubbled for 1 hour. Thereafter, 189.33 g of potassium carbonate was added and subjected to azeotropic dehydration by heating and stirring at 140 ° C. Thereafter, heating was continued while toluene was distilled off. Total heating time was 5 hours. The mixture was allowed to cool at room temperature to obtain an NMP / DMSO mixed solution of the second polymer compound. The obtained second polymer compound had Mn of 1.9 × 10 ⁴ and Mw of 3.6 × 10 ⁴ .

(Synthesis of block copolymer)
While stirring the obtained NMP / DMSO mixed solution of the second polymer compound, the total amount of DMSO solution of the first polymer compound and 1035 g of NMP were added thereto, and a block copolymerization reaction was performed at 150 ° C. for 41 hours. It was.

  The obtained reaction solution was dropped into a large amount of 2N hydrochloric acid and immersed for 1 hour. Thereafter, the produced precipitate was filtered off and then immersed again in 2N hydrochloric acid for 1 hour. The obtained precipitate was filtered and washed with water, and then immersed in a large amount of hot water at 95 ° C. for 1 hour. And after filtering off from hot water, it dried at 80 degreeC overnight and the block copolymer was obtained. Table 1 shows the solvent composition during the block copolymerization reaction.

(Production of polymer electrolyte membrane)
The obtained block copolymer was made into an NMP solution of about 20% by weight and developed on a glass plate, and then the solvent was dried at 80 ° C. After drying, the film formed on the glass plate was immersed in a 2N hydrochloric acid aqueous solution, then washed with deionized water until the washing water became neutral, and dried to give a polymer of Example 2 having a thickness of 22 μm. An electrolyte membrane was obtained. This polymer electrolyte membrane had Mn of 8.3 × 10 ⁴ and Mw of 20.9 × 10 ⁴ .
[Example 3]

(Synthesis of the first polymer compound)
In a flask equipped with an azeotropic distillation apparatus, in an argon atmosphere, 81.69 g of dipotassium 4,4′-difluorodiphenylsulfone-3,3′-disulfonate, 31.26 g of potassium 2,5-dihydroxybenzenesulfonate, 493 g of DMSO, And 77g of toluene was added, and argon gas was bubbled for 1 hour, stirring at room temperature.

Thereafter, 19.91 g of potassium carbonate was added, and azeotropic dehydration was performed by heating and stirring at 140 ° C. Thereafter, heating was continued while distilling off the toluene to obtain a DMSO solution of the first polymer compound. Total heating time was 14 hours. The resulting solution was allowed to cool at room temperature. Mn of the obtained 1st high molecular compound was 9.0 * 10 < ³ >, and Mw was 1.7 * 10 < ⁴ >.

(Synthesis of second polymer compound)
To a flask equipped with an azeotropic distillation apparatus, 62.43 g of 4,4′-difluorodiphenylsulfone, 43.12 g of 2,6-dihydroxynaphthalene, 460 g of NMP and 77 g of toluene are added under an argon atmosphere, and the mixture is stirred at room temperature. Then, argon gas was bubbled for 1 hour.

Thereafter, 40.93 g of potassium carbonate was added and subjected to azeotropic dehydration by heating and stirring at 140 ° C. Thereafter, heating was continued while distilling off toluene. The total heating time was 3 hours. The mixture was allowed to cool at room temperature to obtain an NMP solution of the second polymer compound. The obtained second polymer compound had Mn of 1.9 × 10 ⁴ and Mw of 3.5 × 10 ⁴ .

(Synthesis of block copolymer)
While stirring the obtained NMP solution of the second polymer compound, the total amount of the DMSO solution of the first polymer compound and 274 g of NMP were added thereto, and the mixture was heated and stirred at 150 ° C. for 21 hours.

  The obtained reaction solution was dropped into a large amount of 2N hydrochloric acid and immersed for 1 hour. Thereafter, the produced precipitate was filtered off and then immersed again in 2N hydrochloric acid for 1 hour. The obtained precipitate was filtered and washed with water, and then immersed in a large amount of hot water at 95 ° C. for 1 hour. And after filtering off from hot water, it dried at 80 degreeC overnight and the block copolymer was obtained. Table 1 shows the solvent composition during the block copolymerization reaction.

(Production of polymer electrolyte membrane)
The obtained block copolymer was made into an NMP solution of about 20% by weight and developed on a glass plate, and then the solvent was dried at 80 ° C. After drying, the membrane formed on the glass plate is immersed in a 2N hydrochloric acid aqueous solution, washed with deionized water until the washing water becomes neutral, and dried to obtain a polymer electrolyte membrane having a thickness of 28 μm. It was. The obtained polymer electrolyte membrane had Mn of 8.0 × 10 ⁴ and Mw of 20.4 × 10 ⁴ .
[Example 4]

(Synthesis of the first polymer compound)
In a flask equipped with an azeotropic distillation apparatus, in an argon atmosphere, 83.78 g of dipotassium 4,4′-difluorodiphenylsulfone-3,3′-disulfonate, 32.01 g of potassium 2,5-dihydroxybenzenesulfonate, 505 g of DMSO, And 79g of toluene was added, and argon gas was bubbled for 1 hour, stirring at room temperature.

Thereafter, 20.39 g of potassium carbonate was added to the obtained mixture, and azeotropic dehydration was performed by heating and stirring at 140 ° C. Thereafter, heating was continued while distilling off the toluene to obtain a DMSO solution of the first polymer compound. Total heating time was 19 hours. The resulting solution was allowed to cool at room temperature. Mn of the obtained 1st high molecular compound was 9.0 * 10 < ³ >, and Mw was 1.7 * 10 < ⁴ >.

(Synthesis of second polymer compound)
In a flask equipped with an azeotropic distillation apparatus, 69.22 g of 4,4′-difluorodiphenylsulfone, 47.45 g of 2,6-dihydroxynaphthalene, 509 g of NMP and 86 g of toluene are added under an argon atmosphere, and the mixture is stirred at room temperature. Then, argon gas was bubbled for 1 hour.

Thereafter, 45.06 g of potassium carbonate was added to the obtained mixture, followed by azeotropic dehydration by heating and stirring at 140 ° C. Thereafter, heating was continued while distilling off toluene. The total heating time was 3 hours. The mixture was allowed to cool at room temperature to obtain an NMP solution of the second polymer compound. The obtained first polymer compound had Mn of 1.6 × 10 ⁴ and Mw of 3.3 × 10 ⁴ .

(Synthesis of block copolymer)
While stirring the obtained NMP solution of the second polymer compound, the total amount of the DMSO solution of the first polymer compound and 290 g of DMSO were added thereto, and a block copolymerization reaction was performed at 150 ° C. for 24 hours. .

  The obtained reaction solution was dropped into a large amount of 2N hydrochloric acid and immersed for 1 hour. Thereafter, the obtained precipitate was filtered off and then immersed again in 2N hydrochloric acid for 1 hour. The resulting precipitate was filtered off and washed with water, and then immersed in a large amount of hot water at 95 ° C. for 1 hour. Then, after separating from hot water, it was dried at 80 ° C. overnight to obtain a block copolymer. Table 1 shows the solvent composition during the block copolymerization reaction.

(Production of polymer electrolyte membrane)
The obtained block copolymer was made into an NMP solution of about 20% by weight and developed on a glass plate, and then the solvent was dried at 80 ° C. After drying, the film formed on the glass plate was immersed in a 2N hydrochloric acid aqueous solution, washed with deionized water until the washing water became neutral, and dried to give a polymer of Example 4 having a thickness of 30 μm. An electrolyte membrane was obtained. The obtained polymer electrolyte membrane had Mn of 9.1 × 10 ⁴ and Mw of 21.5 × 10 ⁴ .
[Comparative Example 1]

(Synthesis of the first polymer compound)
In a flask equipped with an azeotropic distillation apparatus, an argon atmosphere was charged with 31.59 g of dipotassium 4,4′-difluorodiphenylsulfone-3,3′-disulfonate, 120.07 g of potassium 2,5-dihydroxybenzenesulfonate, 1892 g of DMSO, Then, 297 g of toluene was added, and argon gas was bubbled for 1 hour while stirring at room temperature.

Thereafter, 76.34 g of potassium carbonate was added to the obtained mixture, and azeotropic dehydration was performed by heating and stirring at 140 ° C. Thereafter, heating was continued while distilling off the toluene to obtain a DMSO solution of the first polymer compound. Total heating time was 15 hours. The resulting solution was allowed to cool at room temperature. Mn of the obtained 1st high molecular compound was 9.0 * 10 < ³ >, and Mw was 1.7 * 10 < ⁴ >.

(Synthesis of second polymer compound)
To a flask equipped with an azeotropic distillation apparatus, 304.55 g of 4,4′-difluorodiphenylsulfone, 205.78 g of 2,6-dihydroxynaphthalene, 2225 g of dimethyl sulfoxide and 350 g of toluene were added under an argon atmosphere at room temperature. While stirring, argon gas was bubbled for 1 hour.

Thereafter, 195.10 g of potassium carbonate was added to the obtained mixture, followed by azeotropic dehydration by heating and stirring at 140 ° C. Thereafter, heating was continued while toluene was distilled off. Total heating time was 5 hours. When the resulting solution was allowed to cool at room temperature, the second polymer compound was precipitated in DMSO, and a DMSO dispersion of the second polymer compound was obtained. The obtained second polymer compound had Mn of 2.2 × 10 ⁴ and Mw of 4.1 × 10 ⁴ .

(Synthesis of block copolymer)
While stirring the DMSO dispersion of the second polymer compound, the whole amount of the DMSO solution of the first polymer compound was added thereto, and a block copolymerization reaction was performed at 120 ° C. for 2 hours and further at 150 ° C. for 4 hours. went. During the reaction, the inside of the system was separated into two phases and became a heterogeneous system.

  The reaction solution after the reaction was dropped into a large amount of 2N hydrochloric acid and immersed for 1 hour. Thereafter, the produced precipitate was filtered off and then immersed again in 2N hydrochloric acid for 1 hour. The obtained precipitate was filtered and washed with water, and then immersed in a large amount of hot water at 95 ° C. for 1 hour. And after filtering off from hot water, it dried at 80 degreeC overnight and the block copolymer was obtained. Table 1 shows the solvent composition during the block copolymerization reaction.

(Production of polymer electrolyte membrane)
The obtained block copolymer was made into an NMP solution of about 20% by weight and developed on a glass plate, and then the solvent was dried at 80 ° C. After drying, the film formed on the glass plate was immersed in a 2N hydrochloric acid aqueous solution, then washed with deionized water until the washing water became neutral, dried, and polymer of Comparative Example 1 having a thickness of 26 μm. An electrolyte membrane was obtained. This polymer electrolyte membrane had Mn of 11.0 × 10 ⁴ and Mw of 38.3 × 10 ⁴ .
[Example 5]

(Synthesis of the first polymer compound)
Polymerization was performed according to the method described in JP-A-2005-248143 to obtain a first polymer compound (C) having a repeating unit represented by the following formula (15). Mn of this polymer compound (C) was 11.8 × 10 ⁴ , and Mw was 30.5 × 10 ⁴ .

(Synthesis of second polymer compound)
In a flask equipped with a reduced-pressure azeotropic distillation apparatus, 23.79 g of 4,4′-dichlorodiphenylsulfone (manufactured by Tokyo Chemical Industry Co., Ltd.), 2,2-bis (4-hydroxyphenyl) propane (Tokyo Chemical Industry) under an argon atmosphere. Kogyo Co., Ltd.) 18.02 g, NMP 184 g and toluene 48 g were added, and argon gas was bubbled while stirring at room temperature.

Thereafter, 11.67 g of potassium carbonate was added to the obtained mixture, and the mixture was heated and stirred at 100 ° C. to perform azeotropic dehydration under reduced pressure. Toluene was distilled off, the temperature was raised to 180 ° C., and the mixture was stirred with heating for 7 hours. Thereafter, 0.38 g of potassium carbonate was added and the mixture was heated and stirred for 1.5 hours. The total heating time was 8.5 hours. The obtained reaction mixture was dropped into a large amount of methanol to precipitate a polymer compound, which was further purified by washing with methanol and water, and then dried to obtain a repeating unit represented by the following formula (16). A second polymer compound (D) having was obtained. Mn of this polymer compound (D) was 1.6 × 10 ⁴ , and Mw was 3.0 × 10 ⁴ .

(Evaluation of solubility of first and second polymer compounds)
The first polymer compound (C) having an ion exchange group obtained above was dissolved in an amount of 0.05 g or more in 0.95 g of DMSO at 25 ° C., but 0 in 0.95 g of NMP. -05g was not completely dissolved. Further, 0.05 g or more of this polymer compound was dissolved in a mixed solvent composed of 0.76 g of DMSO and 0.19 g of NMP.

  On the other hand, the second polymer compound (D) having no ion-exchange group was dissolved in an amount of 0.5 g or more in 9.5 g of NMP at 25 ° C., but in the case of 9.5 g of DMSO, it was 0.8. 5 g was not completely dissolved. In addition, 0.5 g or more of this polymer compound was dissolved in a mixed solvent composed of 1.9 g of NMP and 7.6 g of DMSO. From the above results, it was confirmed that the polymer compound (C) and the polymer compound (D) can be dissolved in a mixed solvent composed of MDSO and NMP.

(Synthesis of block copolymer)
In a flask equipped with a reduced pressure azeotropic distillation apparatus, in an argon atmosphere, 2.03 g of the second polymer compound (D) and 2,5′-di, which is a raw material monomer of the first polymer compound (C). 5.68 g of sodium chlorobenzenesulfonate, 8.55 g of 2,2′-bipyridyl (manufactured by Wako Pure Chemical Industries, Ltd.), 104 g of DMSO, 28 g of NMP, and 53 g of toluene were added, and the mixture was heated and stirred at 100 ° C., followed by azeotropic distillation under reduced pressure. Dehydrated. Then, toluene was distilled off and cooled to 70 ° C. Next, 15.06 g of bis (1,5-cyclooctadiene) nickel (0) (manufactured by Kanto Chemical Co., Inc.) was added thereto and stirred for 3 hours. Thus, the first polymer compound (C) was synthesized and a copolymerization reaction between the first polymer compound (C) and the second polymer compound (D) was caused.

  The obtained reaction solution was dropped into a large amount of methanol, and a polymer was precipitated and separated by filtration. Then, after washing and filtering with 6 mol / L hydrochloric acid were repeated several times, the filtrate was washed with water until it became neutral, and then immersed in a large amount of hot water at 95 ° C. for 1 hour. And after filtering off from hot water, the block copolymer was obtained by drying. Table 1 shows the solvent composition during the block copolymerization reaction.

(Production of polymer electrolyte membrane)
The obtained block copolymer was made into an about 10% by weight NMP solution, which was spread on a glass plate, and then the solvent was dried at 80 ° C. After drying, the film formed on the glass plate was immersed in a 2N hydrochloric acid aqueous solution, then washed with deionized water until the washing water became neutral, and dried to dry the polymer of Example 5 having a thickness of 20 μm. An electrolyte membrane was obtained. The obtained polymer electrolyte membrane had Mn of 9.5 × 10 ⁴ and Mw of 18.5 × 10 ⁴ .
[Comparative Example 2]

(Synthesis of block copolymer)
In a flask equipped with a vacuum azeotropic distillation apparatus, in an argon atmosphere, 2.34 g of the second polymer compound (D) and 2,5′-di, which is a raw material monomer of the first polymer compound (C). 5.65 g of sodium chlorobenzenesulfonate, 9.29 g of 2,2′-bipyridyl, 141 g of NMP, and 59 g of toluene were added, and the mixture was heated and stirred at 100 ° C. to perform azeotropic dehydration under reduced pressure. Then, toluene was distilled off and cooled to 70 ° C. Next, 14.87 g of bis (1,5-cyclooctadiene) nickel (0) was added thereto, and the mixture was stirred for 3 hours. Thus, the first polymer compound (C) was synthesized, and a copolymerization reaction between the first polymer compound (C) and the second polymer compound (D) was caused.

  The obtained reaction solution was dropped into a large amount of methanol, and a polymer was precipitated and separated by filtration. Then, after washing and filtering with 6 mol / L hydrochloric acid were repeated several times, the filtrate was washed with water until it became neutral, and then immersed in a large amount of hot water at 95 ° C. for 1 hour. And after filtering off from hot water, the block copolymer was obtained by drying. Table 1 shows the solvent composition during the block copolymerization reaction.

(Production of polymer electrolyte membrane)
The obtained block copolymer was made into an about 25 wt% NMP solution, which was developed on a glass plate, and then the solvent was dried at 80 ° C. After drying, the film formed on the glass plate was immersed in a 2N hydrochloric acid aqueous solution, then washed with deionized water until the washing water became neutral, dried, and the polymer of Comparative Example 2 having a thickness of 44 μm. An electrolyte membrane was obtained. The obtained polymer electrolyte membrane had Mn of 2.7 × 10 ⁴ and Mw of 5.4 × 10 ⁴ .

［特性評価］

[Characteristic evaluation]

  Using the polymer electrolyte membranes of Examples 1 to 5 and Comparative Examples 1 and 2, the proton conductivity, ion exchange capacity, water absorption rate, and molecular weight were measured according to the following method. The results obtained are summarized in Table 2.

(Measurement of proton conductivity (σ))
Each polymer electrolyte membrane is a strip-shaped membrane sample having a width of 1.0 cm, and a platinum plate (width: 5.0 mm) is pressed against the surface so that the interval is 1.0 cm, and 80 ° C. and a relative humidity of 90%. The sample was held in a constant temperature and humidity chamber, and the AC impedance between the platinum plates at 10 ⁶ to 10 ⁻¹ Hz was measured. Then, the obtained value was substituted into the following formula to calculate the proton conductivity (σ) (S / cm) of each polymer electrolyte membrane.
σ (S / cm) = 1 / (R × d)
[In the equation, the real component of the complex impedance when the imaginary component of the complex impedance is 0 on the Cole-Cole plot is R (Ω). d represents the film thickness (cm) of the strip-shaped film sample. ]

(Measurement of ion exchange capacity)
After weighing a predetermined amount of each of the polymer electrolyte membranes of Examples 1 to 5 and Comparative Examples 1 and 2, they were each immersed in a 0.1N sodium hydroxide standard aqueous solution for 2 hours. Thereafter, this solution was titrated with a 0.1N aqueous hydrochloric acid solution, and the ion exchange capacity (meq / g) of each polymer electrolyte membrane was calculated from the neutralization point.

(Measurement of water absorption)
The polymer electrolyte membranes of Examples 1 to 5 and Comparative Examples 1 and 2 were sufficiently dried and their weights were measured. The fully dried membrane was immersed in water at 100 ° C. for 2 hours, and its weight was measured. And the weight change before and behind immersing a film | membrane in water was calculated | required, and the change rate was made into the water absorption rate.

(Measurement of number average molecular weight and weight average molecular weight, and evaluation of molecular weight distribution of polymer electrolyte membrane)
For the first polymer compound, the second polymer compound, and the polymer electrolyte membrane in Examples 1 to 5 and Comparative Examples 1 and 2, the number average molecular weight (Mn) and the weight average molecular weight ( Mw) was measured. That is, the first polymer compound of Reference Example 1, Examples 1 to 4 and Comparative Example 1 was subjected to the following condition (1), and the second polymer of Reference Example 2, Examples 1 to 4 and Comparative Example 1 was used. For the polymer compound and the polymer electrolyte, the gel permeation was performed under the condition (2) below, and for the first and second polymer compounds of Example 5 and Comparative Example 2 under the condition (3) below. The analysis by an oscillation chromatography (GPC) was performed and Mn and Mw of polystyrene conversion were computed.

  And the molecular weight distribution (Mw / Mn) of each polymer electrolyte membrane was computed from the obtained value. The Mn and Mw of the first polymer compound, the second polymer compound, and the polymer electrolyte membrane in Examples 1 to 5 and Comparative Examples 1 to 2 are as described above. The molecular weight distribution of each polymer electrolyte membrane is shown in Table 2 together.

<GPC measurement conditions>
Condition (1)
GPC measuring device: Hitachi L-6200 low pressure column: TSKgel α-M
Column temperature: 40 ° C
Mobile phase solvent: 50 mM ammonium acetate / water: acetonitrile = 7: 3
Solvent flow rate: 0.6 mL / min

Condition (2)
GPC measuring device: HLC-8220 manufactured by TOSOH
Column: Two AT-80Ms manufactured by Shodex are connected in series Column temperature: 40 ° C
Mobile phase solvent: DMAc (added LiBr to 10 mmol / dm ³ )
Solvent flow rate: 0.5 mL / min

Condition (3)
GPC measuring device: Prominence GPC system column manufactured by Shimadzu Corporation: TSKgel GMH _HR- M manufactured by TOSOH
Column temperature: 40 ° C
Mobile phase solvent: DMF (LiBr added to 10 mmol / dm ³ )
Solvent flow rate: 0.5 mL / min

  From Table 2, the polymer electrolyte membranes of Examples 1 to 5 comprising a block copolymer obtained by block copolymerization of a first polymer compound and a second polymer compound in a mixed solvent have high proton conductivity. In addition, the film was found to be a homogeneous film having a small molecular weight distribution.

It is a figure which shows typically the cross-sectional structure of the fuel cell which concerns on suitable embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Fuel cell, 12 ... Polymer electrolyte membrane, 14a, 14b ... Catalyst layer, 16a, 16b ... Gas diffusion layer, 18a, 18b ... Separator, 20 ... MEA.

Claims (30)

  A step of obtaining a polymer in which a first polymer compound having an ion exchange group and a second polymer compound having substantially no ion exchange group are bonded in a mixed solvent containing two or more solvents. The manufacturing method of the block copolymer characterized by having.   The method for producing a block copolymer according to claim 1, wherein the mixed solvent contains a good solvent for the first polymer compound.   The method for producing a block copolymer according to claim 1 or 2, wherein the mixed solvent contains a good solvent for the second polymer compound.   The method for producing a block copolymer according to any one of claims 1 to 3, wherein the mixed solvent contains 20% by mass or more of a good solvent for the first polymer compound.   The method for producing a block copolymer according to any one of claims 1 to 4, wherein the mixed solvent contains 20% by mass or more of a good solvent for the second polymer compound.   The method for producing a block copolymer according to any one of claims 1 to 5, wherein the ion exchange group is a cation exchange group.   The method for producing a block copolymer according to any one of claims 1 to 6, wherein the ion exchange group is a sulfonic acid group.   The block copolymer according to any one of claims 1 to 7, wherein at least one of the first polymer compound and the second polymer compound is an aromatic polymer compound. Manufacturing method.   The method for producing a block copolymer according to any one of claims 1 to 8, wherein both the first polymer compound and the second polymer compound are aromatic polymer compounds. .   The method for producing a block copolymer according to any one of claims 1 to 9, wherein the molecular weight of the first polymer compound is 2000 or more.   The method for producing a block copolymer according to any one of claims 1 to 10, wherein the molecular weight of the second polymer compound is 2000 or more.   The mixed solvent includes a good solvent for the first polymer compound and a good solvent for the second polymer compound, and a relative dielectric constant of the good solvent for the first polymer compound is 40.0 or more. The method for producing a block copolymer according to any one of claims 1 to 11, wherein the good dielectric constant of the second polymer compound is less than 40.0.   The absolute value of the difference between the relative permittivity of the good solvent of the first polymer compound and the relative permittivity of the good solvent of the second polymer compound is 5.0 or more. 12. A process for producing a block copolymer according to 12.   The method for producing a block copolymer according to any one of claims 1 to 13, wherein the good solvent for the first polymer compound is dimethyl sulfoxide.   The method for producing a block copolymer according to any one of claims 1 to 14, wherein a good solvent for the second polymer compound is N-methylpyrrolidone. The first polymer compound is a compound having a structure represented by the following general formula (7) and having an ion exchange group in the structure. A method for producing a block copolymer according to claim 1.

[In the formula, Ar ⁷¹ represents an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, or 2 to 20 carbon atoms. A divalent aromatic group optionally having an acyl group, X ⁷¹ represents a direct bond, an oxygen atom, a sulfur atom, a carbonyl group or a sulfonyl group, and d is an integer of 5 or more. ] The first polymer compound is a compound having a structure represented by the following general formula (1a), (1b) or (1c), and having an ion exchange group in the structure. The manufacturing method of the block copolymer as described in any one of Claims 1-15.

[In formula, Ar < ¹¹ >, Ar < ¹² >, Ar < ¹³ >, Ar < ¹⁴ >, Ar < ¹⁵ >, Ar < ¹⁶ > and Ar < ¹⁷ > are respectively independently a C1-C20 alkyl group, a C1-C20 alkoxy group, carbon number A divalent aromatic group optionally having 6 to 20 aryl groups, 6 to 20 aryloxy groups or 2 to 20 carbon atoms acyl groups, X ¹¹ , X ¹² , X ¹³ , X ¹⁴ and X ¹⁵ each independently represent an oxygen atom or a sulfur atom, Y ¹¹ and Y ¹² each independently represent a carbonyl group or a sulfonyl group, and p, q and r each independently represent 5 It is an integer above. ] The method for producing a block copolymer according to any one of claims 1 to 15, wherein the first polymer compound is a compound having a structure represented by the following general formula (2). .

[Wherein Y ²¹ represents a carbonyl group or a sulfonyl group, s and t are each independently 0 or 1, at least one of which is 1, u is 0, 1 or 2; Is 1 or 2, and w is an integer of 5 or more. ] The method for producing a block copolymer according to any one of claims 1 to 15, wherein the first polymer compound is a compound having a structure represented by the following general formula (17). .

[ ^Wherein X ¹⁷¹ is a direct bond or an organic group, f is an integer from 1 to the number of substitutable sites in X ¹⁷¹ , g is 1 or 2, and l is an integer of 5 or more. is there. ] The method for producing a block copolymer according to any one of claims 1 to 19, wherein the second polymer compound is a compound having a structure represented by the following general formula (3). .

[In the formula, Ar ³¹ represents an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, or 2 to 20 carbon atoms. And X ³¹ represents a direct bond, an oxygen atom, a sulfur atom, a carbonyl group or a sulfonyl group, and z is an integer of 5 or more. ] The method for producing a block copolymer according to any one of claims 1 to 19, wherein the second polymer compound is a compound having a structure represented by the following general formula (4). .

[Wherein, Ar ⁴¹ , Ar ⁴² and Ar ⁴³ each independently represent an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or 6 to 20 carbon atoms. An aryloxy group or a divalent aromatic group optionally having an acyl group having 2 to 20 carbon atoms, X ⁴¹ and X ⁴² each independently represent an oxygen atom or a sulfur atom, and Z ⁴¹ Represents a carbonyl group or a sulfonyl group, and h is an integer of 5 or more. ] The method for producing a block copolymer according to any one of claims 1 to 19, wherein the second polymer compound is a compound having a structure represented by the following general formula (5). .

[In the formula, Ar ⁵¹ represents an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, or 2 to 20 carbon atoms. A divalent aromatic group optionally having an acyl group, X ⁵¹ and X ⁵² each independently represents an oxygen atom or a sulfur atom, and R ⁵¹ and R ⁵² each independently represent a carbon atom. C 1 -C 20 alkyl group, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryl group or an acyl group having 2 to 20 carbon atoms having from 6 to 20 carbon ^{atoms, Z 51} is , A carbonyl group or a sulfonyl group, j and k are each independently an integer of 0 to 4, and i is an integer of 5 or more. ]   The block copolymer which can be obtained with the manufacturing method as described in any one of Claims 1-22.   The block copolymer according to claim 23, having an ion exchange capacity of 0.1 to 4 meq / g.   A polymer electrolyte comprising the block copolymer according to claim 23 or 24 as a proton conductive component.   A catalyst composition comprising the polymer electrolyte according to claim 25 and a catalyst.   A polymer electrolyte membrane comprising the polymer electrolyte according to claim 25. A polymer electrolyte membrane, and a catalyst layer formed on the polymer electrolyte membrane,
The membrane-electrode assembly, wherein the polymer electrolyte membrane contains the polymer electrolyte according to claim 25. A polymer electrolyte membrane, and a catalyst layer formed on the polymer electrolyte membrane,
The membrane-electrode assembly, wherein the catalyst layer contains the polymer electrolyte according to claim 25 and a catalyst. A pair of separators, and a membrane-electrode assembly disposed between the pair of separators,
30. A fuel cell, wherein the membrane-electrode assembly is the membrane-electrode assembly according to claim 28 or 29.

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