JP2007084739A - Ionic group-bearing polymer, polyelectrolyte material, polyelectrolyte component, membrane electrode assembly, and polyelectrolyte-type fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ionic group-bearing polymer excellent in proton conductivity, especially proton conductivity under low-humidifying conditions, and swelling resistance, to provide a polyelectrolyte material made thereof, to provide a polyelectrolyte component made from the above material, to provide a membrane electrode assembly constituted of the above components, and to provide a polyelectrolyte-type fuel cell using the above composite. <P>SOLUTION: The ionic group-bearing polymer has ionic groups each comprising a structure of the formula(A1)( wherein, G<SP>1</SP>is a substituent selected from a ketone group and a sulfone group ). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a polymer having an ionic group excellent in proton conductivity, particularly proton conductivity under low humidification conditions and swelling resistance, a polymer electrolyte material, and a polymer electrolyte component comprising the same, The present invention relates to a membrane electrode assembly and a polymer electrolyte fuel cell.

  Polymers having an ionic group are used, for example, in medical material applications, filtration applications, concentration applications, ion exchange resin applications, various structural material applications, coating material applications, polymer actuators, electrochemical applications, and the like.

  In electrochemical applications, polymers with ionic groups are used in capacitors, fuel cells, redox flow batteries, water electrolyzers and chloroalkali electrolyzers as polymer electrolyte materials, polymer electrolyte components or membrane electrode composites. Has been.

  Among these, the fuel cell is a power generation device that has low emissions, high energy efficiency, and low environmental burden. For this reason, it is a technology that attracts attention in the recent increase in global environmental protection. A fuel cell is a power generation device that is expected to be used in the future as a power generation device for a relatively small-scale distributed power generation facility or a moving body such as an automobile or a ship. In addition, instead of secondary batteries such as nickel metal hydride batteries and lithium ion batteries, or by hybridization with secondary batteries, it is expected to be mounted on small mobile devices such as mobile phones and personal computers.

  In polymer electrolyte fuel cells (hereinafter also referred to as PEFC), in addition to conventional batteries that use hydrogen gas as fuel, there is no need to reform fuel such as methanol into hydrogen gas. Direct fuel cells that supply directly are also attracting attention. Although the direct fuel cell has a lower output than the conventional PEFC, the fuel is liquid and does not use a reformer, so the energy density is high and the power generation time per filling is long. is there.

  In the polymer electrolyte material for a direct fuel cell, in addition to the performance required for a conventional polymer electrolyte material for PEFC using hydrogen gas as a fuel, suppression of fuel permeation is also required. In particular, fuel permeation through a polymer electrolyte membrane using a polymer electrolyte material is also called fuel crossover or chemical short, and causes a problem that the battery output and energy capacity are reduced.

  Further, the direct fuel cell is required to have a performance different from that of a conventional PEFC using hydrogen gas as a fuel. That is, in a direct type fuel cell, a fuel such as a methanol aqueous solution reacts with the catalyst layer of the anode electrode to produce protons, electrons, and carbon dioxide at the anode electrode, and the electrons are conducted to the electrode substrate, and the protons are polymer electrolyte. The carbon dioxide passes through the electrode substrate and is released out of the system. For this reason, in addition to the required characteristics of the anode electrode of the conventional PEFC, fuel permeability such as aqueous methanol solution and carbon dioxide emission are also required. Further, in the cathode electrode of the direct type fuel cell, in addition to the reaction similar to that of the conventional PEFC, fuel such as methanol that has permeated through the electrolyte membrane and oxidizing gas such as oxygen or air are mixed with carbon dioxide in the cathode electrode catalyst layer. Reactions that produce water also occur. For this reason, since generated water becomes more than conventional PEFC, it is necessary to discharge water more efficiently.

  Conventionally, a perfluoro proton conductive polymer membrane represented by “Nafion” (manufactured by DuPont, trade name) has been used as a polymer electrolyte membrane. However, these perfluoro proton conductive polymer membranes have a problem that the fuel permeation amount of methanol or the like is large in the direct fuel cell, and the cell output and energy capacity are not sufficient. Perfluoro proton conductive polymers are also very expensive in terms of using fluorine.

  Therefore, non-fluorine proton conductor polymer electrolytes are desired from the market, and some efforts have already been made on polymer electrolyte membranes based on non-fluorine polymers.

For example, an aromatic polyether polymer having a benzophenone moiety having one ionic group or a diphenylsulfone moiety having one ionic group (see, for example, Non-Patent Document 1 and Patent Document 1), Aromatic polyether polymers having a benzophenone moiety having two ionic groups or a diphenylsulfone moiety having two ionic groups have been proposed (see, for example, Patent Document 2). In this technique, there is a problem that it is difficult to achieve both proton conductivity of the obtained polymer electrolyte material, particularly proton conductivity under low humidification conditions and swelling resistance.
Proceedings of the 53rd Annual Meeting of the Polymer Society of Japan, II Pd120, 53 (1), 1640 (2004) JP 2005-015607 A International Publication WO2004 / 079844 Pamphlet

  The present invention has been achieved as a result of examination in view of the background of such prior art, and has an ionic group excellent in both proton conductivity, particularly proton conductivity under low humidification conditions and swelling resistance. It is an object of the present invention to provide a polymer and a polymer electrolyte material, and further to provide a polymer electrolyte fuel cell with high efficiency by using a polymer electrolyte component and a membrane electrode assembly made of the polymer and the polymer electrolyte material.

  In order to achieve the above object, according to the present invention, there is provided a polymer having an ionic group characterized by containing a structure of the following formula (A1).

[In Formula (A1), G ¹ represents a substituent selected from a ketone group and a sulfone group. X represents H and any cation. m and n represent an integer of 0 to 4, and 3 ≦ (m + n) ≦ 8. The structure represented by the formula (A1) may be optionally substituted. ]
The present invention also provides a polymer electrolyte material, a polymer electrolyte component, a membrane electrode assembly, and a polymer electrolyte fuel cell made of the above polymer having an ionic group.

  According to the present invention, it is possible to obtain a polymer and a polymer electrolyte material having an ionic group excellent in both proton conductivity, particularly proton conductivity under low humidification conditions, and swelling resistance. A high-efficiency polymer electrolyte fuel cell can be obtained by using the polymer electrolyte component and the membrane electrode assembly.

  The present invention will be specifically described below.

  The polymer having an ionic group according to the present invention is characterized by containing a structure represented by the following formula (A1).

[In Formula (A1), G ¹ represents a substituent selected from a ketone group and a sulfone group. X represents H and any cation. m and n represent an integer of 0 to 4, and 3 ≦ (m + n) ≦ 8. The structure represented by the formula (A1) may be optionally substituted. ]
In formula (A1), G ¹ represents a substituent selected from a ketone group and a sulfone group. Here, the ketone group is a group represented by the formula (g-1), and the sulfone group is a group represented by the formula (g-2).

  X represents H and any cation. Suitable cations include cations such as various alkali metals, various alkaline earth metals, and various ammoniums. Among them, cations of Li, Na, and K are particularly preferable. Moreover, you may use together multiple types of H or a cation as X.

m and n represent an integer of 0 to 4, and 3 ≦ (m + n) ≦ 8. When (m + n) is 3 or more, it becomes possible to obtain a polymer having an ionic group excellent in both proton conductivity, particularly proton conductivity under low humidification conditions and swelling resistance. This is presumably due to the fact that a large number of ionic groups (sulfonic acid groups) are concentrated in the vicinity of G ¹ which is a polar group. Introducing many sulfonic acid groups into an aromatic ring is generally not easy and leads to an increase in cost, and therefore it is more preferable that 3 ≦ (m + n) ≦ 4.

The polymer having an ionic group of the present invention preferably has a skeleton containing a repeating unit of the following formula (P1). This is because such a skeleton is excellent in hydrolysis resistance, and a tough polymer excellent in various mechanical properties can be obtained.

^{-Y 11 -Z 11 -Y 21 -Z 21} - (P1)

[In Formula (P1), Y ¹¹ and Y ¹² each represent O or S. Z ¹¹ represents a divalent group containing an aromatic ring, and Z ¹¹ may be optionally substituted. Z ²¹ represents a group represented by the formula (A1). ]
In formula (P1), Y ¹¹ and Y ¹² each represent O or S, and more preferably O.

In formula (P1), Z ¹¹ represents a divalent group containing an aromatic ring, and Z ¹¹ may be optionally substituted, but proton conductivity, fuel blocking property, resistance to swelling by fuel, and production From the viewpoint of obtaining excellent properties in both solubility in the membrane solvent, suitable examples thereof include groups represented by the following formulas (Z1-1) to (Z1-12), and the following formula (B1). To (B3), among which groups represented by formulas (B1) to (B3) are particularly preferable.

[In Formulas (B1) to (B3), Q ¹ represents a substituent selected from a direct bond, a methylene group, a carbonyl group, O and S. Q ² represents a substituent selected from H, a methyl group, and a phenyl group. Q ³ represents a substituent selected from a carbonyl group and a sulfonyl group. Q ⁴ represents a substituent selected from O, S and N—R ¹ . R ¹ represents a substituent selected from H, an alkyl group, and an aryl group. The structures represented by formulas (B1) to (B3) may be optionally substituted. ]
In formula (B1), Q ¹ represents a direct bond, a methylene group, a carbonyl group, a substituent selected from O and S, and most preferably a direct bond.

In formula (B2), Q ² represents a substituent selected from H, an alkyl group, and an aryl group, preferably H, a methyl group, and a phenyl group, and most preferably a phenyl group.

In the formula (B3), Q ³ represents a substituent selected from a carbonyl group and a sulfonyl group, and is preferably a carbonyl group. Q ⁴ represents a substituent selected from O, S and N—R ¹ , preferably O and N—R ¹ , and most preferably O. R ¹ represents a substituent selected from H, an alkyl group, and an aryl group, and is preferably H or an alkyl group having 1 to 3 carbon atoms.

  The groups represented by the formulas (Z1-1) to (Z1-12) and the groups represented by the formulas (B1) to (B3) may be optionally substituted. Any number of substituents may be substituted in any number, but preferred substituents are alkyl groups having 1 to 3 carbon atoms, halogenated alkyl groups, phenyl groups, halogen groups and ionic groups. The number of preferable substituents is 0-8.

In the formula (P1), Z ²¹ represents a group represented by the formula (A1).

The polymer having an ionic group of the present invention preferably further has a skeleton containing a repeating unit of the following formula (P2).

^{-Y 12 -Z 12 -Y 22 -Z 22} - (P2)

[In Formula (P2), Y ¹² and Y ²² each represent O or S. Z ¹² represents a divalent group containing an aromatic ring, and Z ¹² may be optionally substituted. Z ²² represents a divalent group containing an aromatic ring having an electron-withdrawing group, and Z ²² may be optionally substituted. ]
In formula (P2), Y ¹² and Y ²² each represent O or S, and more preferably O.

In the formula (P2), Z ¹² represents a divalent group containing an aromatic ring, and Z ¹² may be optionally substituted. A preferred example thereof is a preferred example of Z ¹¹ in the formula (P1). Similar to the example.

In the formula (P2), Z ²¹ represents a divalent group containing an aromatic ring having an electron-withdrawing group, and Z ²¹ may be optionally substituted, but proton conductivity, fuel cutoff, swelling due to fuel From the viewpoint of obtaining excellent properties in both resistance to water and solubility in a film-forming solvent, suitable examples thereof are groups represented by the following formulas (Z2-1) to (Z2-12). Among them, a group represented by the formula (Z2-1) and a group represented by the formula (Z2-2) are particularly preferable.

Z ²² may be optionally substituted, but preferred substituents are an alkyl group having 1 to 3 carbon atoms, a halogenated alkyl group, a phenyl group, a halogen group and an ionic group. The number of preferable substituents is 1 to 9 including the electron withdrawing group.

The polymer having an ionic group of the present invention preferably has a skeleton containing a repeating unit of the following formula (P3).

^{-Y 13 -Z 13 -Y 23 -Z 23} - (P3)

[In Formula (P3), Y ¹³ and Y ²³ each represent O or S. Z ¹³ represents a divalent group containing an aromatic ring, and Z ¹³ may be optionally substituted. Z ²³ represents a group represented by the following formula (A2). ]

[In Formula (A2), G ² represents a substituent selected from a ketone group and a sulfone group. X represents H and any cation. ]
In formula (P3), Y ¹³ and Y ²³ each represent O or S, and more preferably O.

In the formula (P3), Z ¹³ represents a divalent group containing an aromatic ring, and Z ¹³ may be optionally substituted. A preferred example thereof is a preferred example of Z ¹¹ in the formula (P1). Similar to the example.

Wherein (A2), G ² represents a substituent selected from a ketone group and sulfone group. Here, the ketone group is a group represented by the formula (g-1), and the sulfone group is a group represented by the formula (g-2).

  X represents H and any cation. Suitable cations include cations such as various alkali metals, various alkaline earth metals, and various ammoniums. Among them, cations of Li, Na, and K are particularly preferable. Moreover, you may use together multiple types of H or a cation as X. The group represented by the formula (A2) may be further optionally substituted, but most preferably not substituted.

In the polymer having ionic groups of the present invention, the number of SO 3 _X groups derived from a group represented by the formula (A1), relative to the total SO 3 _X groups of a polymer having the ionic group, 0. The range of 1% to 100% is preferable, 1% to 90% is more preferable, and 5% to 70% is more preferable. If the ratio of the number of SO ₃ X groups derived from the group represented by the formula (A1) is too small, it is difficult to obtain the effects of the present invention, which is not preferable. If the ratio of the number of SO ₃ X groups derived from the group represented by the formula (A1) is too large, the production cost of the polymer may increase, which may be undesirable.

The polymer having an ionic group of the present invention preferably has a skeleton containing the repeating unit of the formula (P1). Such a polymer can be obtained, for example, by the following method. ^{That, H-Y 11 -Z 11 -Y} 21 -H ^{[Y 11, Z 11} and ^{Y 21} have the same meanings as the symbols in the formula (P1). A compound and / or a salt thereof], ^E-Z 21 -E ^{[Z 21} has the same meaning as the symbols in the formula (P1). E represents F or Cl. ] The aromatic halide compound represented by this is the method of carrying out condensation polymerization under high temperature. In the condensation polymerization, a deoxidizing agent such as potassium carbonate can be used as necessary. In addition, aprotic solvents such as diphenylsulfone, dimethylformamide, dimethylsulfoxide, dimethylacetamide, N-methyl-2-pyrrolidone, dimethylimidazolidinone can be used. When water is generated during the condensation reaction, it is also preferable to add an azeotropic solvent such as toluene and remove the water by azeotropic distillation. The reaction temperature is about 100 to 300 ° C., and the reaction time is about 1 to 72 hours.

The polymer having an ionic group of the present invention preferably further has a skeleton containing the repeating unit of the formula (P2) and / or the formula (P3). In the case of having a skeleton containing the repeating unit of the formula (P2), H—Y ¹² —Z ¹² —Y ²² —H [Y ¹² , Z ¹² and Y ²² are symbols in the formula (P2). Means the same. A compound and / or a salt thereof], ^E-Z 22 -E ^{[Z 22} has the same meaning as the symbols in the formula (P2). E represents F or Cl. A skeleton containing the repeating unit of the formula (P2) is obtained by adding the aromatic halide compound represented by the formula (P2). If having a skeleton comprising a repeating unit of the formula (P3), the symbols of the polymerization system further ^{H-Y 13 -Z 13 -Y 23} -H ^{[Y 13, Z 13} and ^{Y 23} are in the formula (P3) Means the same. And a salt thereof, and EZ ²³ -E [Z ²³ has the same meaning as the symbol in formula (P3). E represents F or Cl. By adding the aromatic halide compound represented by the formula, a skeleton containing the repeating unit of the formula (P3) can be obtained.

The molecular weight of the polymer having an ionic group of the present invention is preferably 10,000 or more, more preferably 20,000 or more in terms of weight average molecular weight. If the molecular weight is too small, the swelling resistance to fuel tends to decrease, which is not preferable. On the other hand, if the molecular weight is too large, the solubility in a solvent is decreased, which is not preferable. Therefore, the molecular weight is preferably 5000000 or less, more preferably 2000000 or less, and even more preferably 1000000 or less.

  The weight average molecular weight of the polymer having an ionic group of the present invention is measured by GPC (gel permeation chromatography). Specifically, using a GPC apparatus equipped with an ultraviolet detector and two GPC columns having an inner diameter of 6.0 mm and a length of 15 cm, an N-methyl-2-pyrrolidone solvent (N-methyl containing 10 mmol / L of lithium bromide) was used. It is measured with a flow rate of 0.2 mL / min in a -2-pyrrolidone solvent, and the weight average molecular weight is obtained by standard polystyrene conversion.

The ionic group of the polymer having an ionic group of the present invention comprises at least a sulfonic acid group or a salt thereof, but it is also preferable to use it in combination with another ionic group. The other ionic group is preferably a negatively charged atomic group, and preferably has proton exchange ability. As such a functional group, a sulfuric acid group (—OSO ₂ (OH) ₂ ), a sulfonimide group (—SO ₂ NHSO ₂ R (R represents an organic group)), a phosphonic acid group (—PO (OH) ₂ ), Phosphoric acid groups (—OPO (OH) ₂ ), carboxylic acid groups (—CO (OH) 2), and salts thereof can be preferably employed. Of these, a sulfonimide group is preferable from the viewpoint of high proton conductivity, and a phosphonic acid group is preferable from the viewpoint of imparting chemical stability.

  In the production of the polymer having an ionic group of the present invention, examples of the method for introducing an ionic group include a method of polymerizing using a monomer having an ionic group and a method of introducing an ionic group by a polymer reaction. .

  As a method of polymerizing using a monomer having an ionic group, a monomer having an ionic group in a repeating unit may be used, and if necessary, an appropriate protecting group may be introduced to perform a deprotecting group after polymerization. . Such a method is described in, for example, Journal of Membrane Science, 197 (2002) 231-242. This method is very preferable because it is easy to control the ion exchange capacity of the polymer and is industrially applicable.

  Next, a method for introducing an ionic group by a polymer reaction will be described with reference to an example. As a method for sulfonating an aromatic polymer, that is, a method for introducing a sulfonic acid group, for example, JP-A-2-16126. The methods described in Japanese Patent Application Laid-Open No. 2-208322 and the like are known. Specifically, for example, sulfonation by reacting an aromatic polymer with a sulfonating agent such as chlorosulfonic acid in a solvent such as chloroform or by reacting in concentrated sulfuric acid or fuming sulfuric acid. Can do. The sulfonating agent is not particularly limited as long as it sulfonates an aromatic polymer, and sulfur trioxide or the like can be used in addition to the above. When the aromatic polymer is sulfonated by this method, the degree of sulfonation can be easily controlled by the amount of the sulfonating agent used, the reaction temperature and the reaction time. Introduction of a sulfonimide group into an aromatic polymer can be achieved, for example, by a method of reacting a sulfonic acid group and a sulfonamide group.

  The content of the sulfonic acid group of the polymer having an ionic group of the present invention can be represented by an ion exchange capacity. The ion exchange capacity of the polymer having an ionic group of the present invention is preferably from 0.01 to 3.5 meq / g, more preferably from 0.1 to 2.5 in terms of proton conductivity and swelling resistance. 5 meq / g. When the ion exchange capacity is lower than 0.01 meq / g, the output performance may be lowered due to low conductivity. When the ion exchange capacity is higher than 3.0 meq / g, sufficient swelling resistance is obtained when used as a polymer electrolyte membrane. And mechanical strength at the time of water content may not be obtained.

  Here, the ion exchange capacity is the molar amount of sulfonic acid groups introduced per unit gram of the polymer having a dry ionic group. In the present invention, the ion exchange capacity is specified by titration.

The titration procedure when the ionic group is a sulfonic acid group is as follows. The measurement shall be performed three times or more and the average shall be taken. A known titration method can be applied to ionic groups other than sulfonic acid groups.
(1) The sample is pulverized by a mill, and in order to make the particle size uniform, the sample is passed through a 50-mesh mesh sieve and the sample passed through the sieve is used as the measurement sample.
(2) Weigh the sample tube (with lid) with a precision balance.
(3) About 0.1 g of the sample of (1) is put into a sample tube and vacuum dried at 40 ° C. for 16 hours.
(4) Weigh the sample tube with the sample and determine the dry weight of the sample.
(5) Dissolve sodium chloride in a 30 wt% aqueous methanol solution to prepare a saturated saline solution.
(6) Add 25 mL of the saturated salt solution of (5) above to the sample, and stir for 24 hours for ion exchange.
(7) Titrate the resulting hydrochloric acid with 0.02 mol / L aqueous sodium hydroxide. Two drops of a commercially available titration phenolphthalein solution (0.1% by volume) as an indicator are added, and the point at which light reddish purple is obtained is the end point.
(8) The ion exchange capacity is obtained by the following formula.

Ion exchange capacity (meq / g) =
[Concentration of sodium hydroxide aqueous solution (mmol / ml) × Drip amount (ml)] / Dry weight of sample (g)
The polymer having an ionic group of the present invention contains other components, for example, an inactive polymer or an organic or inorganic compound that does not have conductivity or ionic conductivity, as long as the object of the present invention is not impaired. It does not matter.

  The polymer having an ionic group of the present invention is preferably used for electrochemical applications as a polymer electrolyte material or a polymer electrolyte component. Examples of the polymer electrolyte component include a polymer electrolyte membrane and an electrode catalyst layer.

  A production method when the polymer electrolyte material of the present invention is used as a polymer electrolyte membrane will be described. As a method of converting the polymer electrolyte material into a membrane, the polymer electrolyte material is made into a solution, suspension or emulsion, and the solution is coated to a desired film thickness, and then the solvent is removed by heating. The method of forming into a film by this, ie, the solvent cast method, is mentioned.

  The solid concentration of the liquid is preferably 1 to 50% by weight, more preferably 5 to 30% by weight, and particularly preferably about 10% by weight.

  As the coating method, methods such as spray coating, brush coating, dip coating, die coating, curtain coating, flow coating, spin coating, and screen printing can be applied.

  The solvent used for film formation is not particularly limited as long as the polymer electrolyte material can be dissolved and then removed. For example, N, N-dimethylacetamide, N, N-dimethylformamide, N-methyl-2-pyrrolidone , Dimethyl sulfoxide, sulfolane, aprotic polar solvents such as 1,3-dimethyl-2-imidazolidinone and hexamethylphosphontriamide, ester solvents such as γ-butyrolactone and butyl acetate, carbonates such as ethylene carbonate and propylene carbonate Solvent, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, alkylene glycol monoalkyl ether such as propylene glycol monoethyl ether, or isopropanol Alcohol solvents, water and mixtures thereof is preferably used, is preferred for high highest solubility aprotic polar solvent.

  Next, the obtained polymer electrolyte membrane is preferably heat-treated after at least a part of the ionic groups is in a metal salt state. The metal of the metal salt may be any metal that can form a salt with sulfonic acid, but from the viewpoint of cost and environmental load, Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, W, and the like are preferable. Among these, Li, Na, K, Ca, Sr, and Ba are more preferable, and Li, Na, and K are more preferable. The temperature of this heat treatment is preferably 150 to 550 ° C, more preferably 160 to 400 ° C, and particularly preferably 180 to 350 ° C. The heat treatment time is preferably 10 seconds to 12 hours, more preferably 30 seconds to 6 hours, and particularly preferably around 1 hour. If the heat treatment temperature is too low, the effect of suppressing fuel permeability is insufficient. On the other hand, if it is too high, the film material tends to deteriorate. If the heat treatment time is less than 10 seconds, the effect of suppressing fuel permeability is insufficient. On the other hand, when it exceeds 12 hours, the film material tends to deteriorate. The polymer electrolyte membrane obtained by the heat treatment can be proton-substituted by being immersed in an acidic aqueous solution as necessary. By molding by this method, the polymer electrolyte membrane of the present invention can achieve both a good balance between proton conductivity and fuel cutoff.

  In the polymer electrolyte membrane of the present invention, the polymer structure can be further cross-linked by means such as radiation irradiation as necessary. By crosslinking such a polymer electrolyte membrane, an effect of further suppressing fuel crossover and swelling with respect to the fuel can be expected, and the mechanical strength may be improved, which may be more preferable. Examples of such radiation irradiation include electron beam irradiation and γ-ray irradiation.

  The film thickness of the polymer electrolyte membrane of the present invention is preferably 1 to 2000 μm. A thickness of more than 1 μm is more preferable for obtaining the strength of a film that can withstand practical use, and a thickness of less than 2000 μm is preferable for reducing the film resistance, that is, improving the power generation performance. A more preferable range of the film thickness is 3 to 500 μm, and a particularly preferable range is 5 to 250 μm. The film thickness can be controlled by the solution concentration or the coating thickness on the substrate.

  In addition, an additive such as a plasticizer, a stabilizer, or a mold release agent used for a general polymer compound may be added to the polymer electrolyte material of the present invention within a range not contrary to the object of the present invention. it can.

  In addition, the polymer electrolyte material of the present invention includes various polymers, elastomers, fillers for the purpose of improving mechanical strength, thermal stability, workability, and the like within a range that does not adversely affect the above-described properties. , Fine particles, various additives, and the like may be contained.

The polymer electrolyte membrane of the present invention preferably has proton conductivity per unit area is 1S · ^{cm -2} or more, 2S · ^{cm -2} or more is more preferable. Proton conductivity can be measured by the constant potential alternating current impedance method, which is performed as quickly as possible after immersing the polymer electrolyte membrane in pure water at 25 ° C. for 24 hours, taking it out in an atmosphere of 25 ° C. and 50% to 80% relative humidity. it can.

By setting the proton conductivity per unit area to 1 S · cm ⁻² or more, when used as a polymer electrolyte membrane for a fuel cell, sufficient proton conductivity, that is, sufficient battery output can be obtained. Higher proton conductivity is preferable, but a membrane with high proton conductivity is likely to be dissolved or disintegrated by a fuel such as methanol water, and the fuel permeation amount tends to increase, so a practical upper limit is 50 S · cm. ^-2 .

Furthermore, the polymer electrolyte membrane of the present invention preferably exhibits high proton conductivity under low humidification. This is because, for example, an automobile fuel cell is required to operate under low humidification. The polymer electrolyte membrane of the present invention specifically, 70 ° C., at a relative humidity of 30%, preferably proton conductivity per unit area is 0.05 S · ^{cm -2} or more, 0.1 S · cm ^{- Two} or more are more preferable. The proton conductivity under low humidification is determined by immersing the polymer electrolyte membrane in pure water at 25 ° C. for 24 hours, leaving it in a constant temperature and humidity chamber at 70 ° C. and 30% relative humidity for 10 hours or more, and It can be measured by a constant potential AC impedance method performed in a wet tank.

Proton conductivity per unit area at 70 ° C. and 30% relative humidity is 0.05 S · cm ⁻² or more, which can be used as a polymer electrolyte membrane for an automobile fuel cell, that is, a necessary battery. Output can be obtained. Higher proton conductivity is preferred, but polymer electrolyte membranes with high proton conductivity tend to be swollen by water and are not preferred. Therefore, the actual proton conductivity per unit area at 70 ° C. and 30% relative humidity is undesirable. A typical upper limit is 50 S · cm ⁻² .

Furthermore, in the polymer electrolyte membrane of the present invention, the swelling ratio with water is preferably 1.2 or less, more preferably 1.1 or less, and even more preferably 1.07 or less. The swelling ratio with water is defined by the following (Formula 1). The sample electrolyte membrane is a strip of about 2 mm × about 10 mm, and the length is measured with a caliper for the length in the longitudinal direction.

Swelling ratio by water = L2 / L1 (Formula 1)

[In (Formula 1), L1 represents the length of the polymer electrolyte membrane after being left in an atmosphere of 20 ° C. and 30% relative humidity for 24 hours. L2 represents the length of the polymer electrolyte membrane after standing in pure water for 24 hours after measuring L1. ]
In the polymer electrolyte membrane of the present invention, the methanol permeation amount per unit area with respect to a 30 wt% methanol aqueous solution at 20 ° C. is preferably 40 μmol · min ⁻¹ · cm ⁻² or less, and 20 μmol · min ⁻¹ · cm. ^-2 or less is more preferable. In the direct fuel cell using the polymer electrolyte membrane, it is desired that the fuel permeation amount is small in order to maintain a high fuel concentration from the viewpoint of obtaining a high output and a high energy capacity in a region where the fuel concentration is high. Because. The amount of methanol permeated is measured after the polymer electrolyte membrane is immersed in pure water at 25 ° C. for 24 hours.

From this viewpoint, 0 μmol · min ⁻¹ · cm ⁻² is most preferable, but from the viewpoint of ensuring proton conductivity, 0.01 μmol · min ⁻¹ · cm ⁻² or more is preferable.

  The polymer electrolyte membrane of the present invention preferably achieves proton conductivity, particularly proton conductivity under low humidification conditions, and swelling resistance at the same time. There is a feature of the film.

  The membrane electrode assembly (MEA) of the present invention is constituted using the polymer electrolyte material of the present invention. Such a membrane electrode assembly is composed of a polymer electrolyte component constituted by using the polymer electrolyte material of the present invention. Examples of such a polymer electrolyte component include a polymer electrolyte membrane and / or an electrode catalyst layer.

The electrode catalyst layer is a layer containing an electrode catalyst that promotes an electrode reaction, an electron conductor, an ion conductor, and the like. As the electrode catalyst contained in the electrode catalyst layer, for example, a noble metal catalyst such as platinum, palladium, ruthenium, rhodium, iridium, gold is preferably used. One of these may be used alone, or two or more of them, such as alloys and mixtures, may be used in combination.

As the electron conductor (conductive material) contained in the electrode catalyst layer, a carbon material or an inorganic conductive material is preferably used from the viewpoint of electronic conductivity and chemical stability. Among these, amorphous and crystalline carbon materials are mentioned. For example, carbon black such as channel black, thermal black, furnace black, and acetylene black is preferably used because of its electronic conductivity and specific surface area. Furnace Black includes "Vulcan XC-72" (R), "Vulcan P" (R), "Black Pearls 880" (R), "Black Pearls 1100" (R), "Black Pearls 1300" ( R), “Black Pearls 2000” (R), “Legal 400” (R), “Ketjen Black” (R) EC, EC600JD, Mitsubishi Chemical Corporation # 3150, # 3250, etc. Examples of acetylene black include “DENKA BLACK” (R) manufactured by Denki Kagaku Kogyo Co., Ltd.

  In addition to carbon black, artificial graphite or carbon obtained from organic compounds such as natural graphite, pitch, coke, polyacrylonitrile, phenol resin, furan resin, and the like can also be used. As the form of these carbon materials, in addition to irregular particles, fibers, scales, tubes, cones, and megaphones can also be used. Moreover, you may use what post-processed these carbon materials.

  Moreover, it is preferable in terms of electrode performance that the electron conductor is uniformly dispersed with the catalyst particles. For this reason, it is preferable that the catalyst particles and the electron conductor are well dispersed in advance as a coating liquid.

  Furthermore, it is also a preferred embodiment that catalyst-supporting carbon in which the catalyst and the electron conductor are integrated is used as the electrode catalyst layer. By using this catalyst-supporting carbon, the utilization efficiency of the catalyst is improved, which can contribute to the improvement of battery performance and cost reduction. Here, even when catalyst-supported carbon is used for the electrode catalyst layer, a conductive agent can be added to further increase the electron conductivity. As such a conductive agent, the above-described carbon black is preferably used.

  In general, various organic and inorganic materials are known as substances having ion conductivity (ion conductor) used in such an electrode catalyst layer. However, when used in a fuel cell, the ion conductivity is improved. A polymer having an ionic group such as a sulfonic acid group, a carboxylic acid group, or a phosphoric acid group (ion conductive polymer) is preferably used. Among these, from the viewpoint of stability of the ionic group, a polymer having ionic conductivity composed of a fluoroalkyl ether side chain and a fluoroalkyl main chain, or a polymer having the ionic group of the present invention is preferably used. As the perfluoro-based ion conductive polymer, for example, “Nafion” (R) manufactured by DuPont, “Aciplex” (R) manufactured by Asahi Kasei Corporation, “Flemion” (R) manufactured by Asahi Glass Co., Ltd. and the like are preferably used. These ion conductive polymers are provided in the electrode catalyst layer in the state of a solution or a dispersion. At this time, the solvent for dissolving or dispersing the polymer is not particularly limited, but a polar solvent is preferable from the viewpoint of the solubility of the ion conductive polymer.

  Since the catalyst and the electronic conductors are usually powders, the ionic conductor usually plays a role of solidifying them. It is preferable from the viewpoint of electrode performance that the ionic conductor is added in advance to a coating liquid mainly composed of electrode catalyst particles and an electron conductor when the electrode catalyst layer is produced, and is applied in a uniformly dispersed state. However, the ion conductor may be applied after the electrode catalyst layer is applied. Here, examples of the method for applying the ion conductor to the electrode catalyst layer include spray coating, brush coating, dip coating, die coating, curtain coating, and flow coating, and are not particularly limited. The amount of the ion conductor contained in the electrode catalyst layer should be appropriately determined according to the required electrode characteristics and the conductivity of the ion conductor used, and is not particularly limited. The range of 1 to 80% is preferable, and the range of 5 to 50% is more preferable. When the ion conductor is too small, the ion conductivity is low, and when it is too much, the gas permeability may be hindered.

  Such an electrode catalyst layer may contain various substances in addition to the catalyst, the electronic conductor, and the ionic conductor. In particular, in order to improve the binding property of the substance contained in the electrode catalyst layer, a polymer other than the ion conductive polymer described above may be included. Examples of such a polymer include fluorine atoms such as polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF), polyhexafluoropropylene (FEP), polytetrafluoroethylene, and polyperfluoroalkyl vinyl ether (PFA). These copolymers, copolymers of monomer units constituting these polymers and other monomers such as ethylene and styrene, or blend polymers can be used. The content of these polymers in the electrode catalyst layer is preferably in the range of 5 to 40% by weight. When there is too much polymer content, there exists a tendency for an electronic and ionic resistance to increase and for electrode performance to fall.

In addition, when the fuel is a liquid or gas, the electrode catalyst layer preferably has a structure through which the liquid or gas easily permeates, and preferably has a structure that promotes the discharge of by-products due to the electrode reaction.

An electrode substrate can be used for the membrane electrode assembly (MEA). As the electrode base material, one having a low electric resistance and capable of collecting or feeding power can be used. Moreover, when using the said electrode catalyst layer also as a collector, it is not necessary to use an electrode base material in particular. Examples of the constituent material of the electrode base material include carbonaceous and conductive inorganic substances. For example, a fired body from polyacrylonitrile, a fired body from pitch, a carbon material such as graphite and expanded graphite, stainless steel, molybdenum And titanium. These forms are not particularly limited, and are used, for example, in the form of fibers or particles. From the viewpoint of fuel permeability, fibrous conductive materials (conductive fibers) such as carbon fibers are preferable. As an electrode base material using conductive fibers, either a woven fabric or a non-woven fabric structure can be used. For example, carbon paper TGP series, SO series manufactured by Toray Industries, Inc., carbon cloth manufactured by E-TEK, etc. are used. As the woven fabric, a plain weave, a twill weave, a satin weave, a crest weave, a binding weave and the like are used without particular limitation. Moreover, as a nonwoven fabric, it does not specifically limit, such as a paper making method, a needle punch method, a spun bond method, a water jet punch method, and a melt blow method. It may also be a knitted fabric. In particular, when carbon fibers are used in these fabrics, carbonized plain fabric using flame-resistant spun yarn is carbonized or graphitized, and flame-resistant yarn is carbonized after being processed into a nonwoven fabric by the needle punch method or water jet punch method. Alternatively, a graphitized nonwoven fabric, a flameproof yarn, a carbonized yarn, or a mat nonwoven fabric by a paper making method using a graphitized yarn is preferably used. In particular, it is preferable to use a non-woven fabric because a thin and strong fabric can be obtained.

  When conductive fibers made of carbon fibers are used for the electrode substrate, examples of the carbon fibers include polyacrylonitrile (PAN) -based carbon fibers, phenol-based carbon fibers, pitch-based carbon fibers, and rayon-based carbon fibers.

  In addition, the electrode base material has a water repellent treatment for preventing gas diffusion / permeability deterioration due to water retention, a partial water repellent treatment for forming a water discharge path, a hydrophilic treatment, and a resistance reduction. The addition of carbon powder can also be performed.

  In the polymer electrolyte fuel cell of the present invention, it is preferable to provide a conductive intermediate layer containing at least an inorganic conductive substance and a hydrophobic polymer between the electrode substrate and the electrode catalyst layer. In particular, when the electrode base material is a carbon fiber woven fabric or a nonwoven fabric having a large porosity, by providing the conductive intermediate layer, it is possible to suppress performance degradation due to the electrode catalyst layer permeating into the electrode base material.

  The method of producing a membrane electrode assembly (MEA) using a polymer electrolyte membrane and an electrode catalyst layer or an electrode catalyst layer and an electrode substrate is not particularly limited. Known methods (for example, the chemical plating method described in “Electrochemistry” 1985, 53, p. 269., “Journal of Electrochemical Society” (J. Electrochem. Soc.), Electrochemical Science and Technology (Electrochemical Science and Technology) , 1988, 135 (9), p.2209. Can be applied. Although integration by hot pressing is a preferred method, the temperature and pressure may be appropriately selected depending on the thickness of the polymer electrolyte membrane, the moisture content, the electrode catalyst layer, and the electrode substrate. Alternatively, the polymer electrolyte membrane may be pressed in a water-containing state, or may be bonded with a polymer having ion conductivity.

  Examples of the fuel for the polymer electrolyte fuel cell of the present invention include hydrogen, methane, ethane, propane, butane, methanol, isopropyl alcohol, acetone, ethylene glycol, diethylene glycol, formic acid, acetic acid, dimethyl ether, diethyl ether, diisopropyl ether, hydroquinone, Examples include organic compounds such as cyclohexane and ascorbic acid. As the fuel of the direct fuel cell that directly supplies liquid fuel, in particular, from the viewpoint of power generation efficiency and simplification of the entire cell system, among these, organic compounds having 1 to 6 carbon atoms and mixtures of these with water are preferable. One kind or a mixture of two or more kinds may be used. Particularly preferred from the viewpoint of power generation efficiency is methanol or an aqueous methanol solution.

  The content of the organic compound having an alkyl group or alkylene group having 1 to 6 carbon atoms in the fuel supplied to the membrane electrode assembly is preferably 20 to 70% by weight. When the content is less than 20% by weight, it is difficult to obtain a practical high energy capacity. When the content exceeds 70% by weight, the balance between power generation efficiency and output tends to be lost, and high power generation efficiency and high output are satisfied at the same time. It is difficult to get practical things to do.

  Hereinafter, the present invention will be described in more detail with reference to examples.

[Measuring method]
The measurement method employed in the examples will be described below.

(1) Weight average molecular weight The weight average molecular weight of the polymer was measured by GPC. Tosoh's HLC-8022GPC is used as an integrated device of an ultraviolet detector and a differential refractometer, and Tosoh's TSK gel SuperHM-H (inner diameter 6.0 mm, length 15 cm) is used as the GPC column. N-methyl-2 -Pyrrolidone solvent (Measured with a N-methyl-2-pyrrolidone solvent containing 10 mmol / L of lithium bromide at a flow rate of 0.2 mL / min, and the weight average molecular weight was determined in terms of standard polystyrene.

(2) Film thickness It measured with the contact-type film thickness meter.

(3) Proton conductivity After immersing the membrane-like sample in pure water at 25 ° C. for 24 hours, take it out in an atmosphere of 25 ° C. and relative humidity 50 to 80%, and determine proton conductivity by the constant potential AC impedance method as quickly as possible. It was measured.

  As the measuring apparatus, Hokuto Denko's electrochemical measurement system HAG5010 (HZ-3000 50V 10A Power Unit, HZ-3000 Automatic Polarization System) and NF circuit design block frequency characteristic analyzer (Frequency Response Analyzer) 5010 are used. The constant potential impedance was measured at 2 ° C. by the two-terminal method, and the proton conductivity was determined from the Nykist diagram. The AC amplitude was 500 mV. As the sample, a membrane having a width of about 10 mm and a length of about 10 to 30 mm was used. As electrodes, platinum wires (two wires) having a diameter of 100 μm were used. The electrodes were arranged on the front side and the back side of the sample film so as to be parallel to each other and perpendicular to the longitudinal direction of the sample film. Proton conductivity was expressed in terms of unit area.

(4) Proton conductivity under low humidification After immersing the polymer electrolyte membrane in pure water at 25 ° C. for 24 hours, the polymer electrolyte membrane was left in a constant temperature and humidity chamber at 70 ° C. and a relative humidity of 30% for 10 hours or more. It measured by the constant potential alternating current impedance method performed in a constant humidity tank. The measuring apparatus and measuring procedure were the same as in (3) above.

(5) Swelling rate by water The electrolyte membrane used was a strip-shaped one having a size of about 2 mm × about 10 mm. As length, the size in the longitudinal direction was measured with calipers. The swelling ratio with water was determined according to Equation (1).

Swelling ratio by water = L2 / L1 (Formula 1)

[In (Formula 1), L1 represents the length of the polymer electrolyte membrane after being left in an atmosphere of 20 ° C. and 30% relative humidity for 24 hours. L2 represents the length of the polymer electrolyte membrane after standing in pure water for 24 hours after measuring L1. ]
(6) Evaluation of membrane electrode assembly and polymer electrolyte fuel cell MEA evaluation was performed by setting the membrane electrode assembly (MEA) in a cell made by Electrochem, and flowing hydrogen gas to the anode side and air to the cathode side. It was. In the evaluation, a constant current was passed through the MEA, and the voltage at that time was measured. The measurement was performed until the current was increased successively until the voltage became 10 mV or less. The product of current and voltage at each measurement point is output, and the maximum value (per unit area of MEA) is defined as output (mW / cm ² ).

[Synthesis Example 1]
109.1 g of 4,4′-difluorobenzophenone, 150 mL of fuming sulfuric acid (50% SO 3) and 50 g of sulfur trioxide were reacted at 180 ° C. for 24 hours. Thereafter, the mixture was poured little by little into a large amount of water, neutralized with NaOH, and 200 g of sodium chloride was added to precipitate the composite. The resulting precipitate was filtered off and separated and purified by a chromatography method to obtain compounds represented by the following formulas (m1), (m2) and (m3).

[Comparative Example 1]
Proton conductivity and methanol permeation amount were evaluated using a commercially available “Nafion” 117 membrane (manufactured by DuPont (trade name)). The Nafion 117 membrane was immersed in 5% hydrogen peroxide water at 100 ° C. for 30 minutes and then in 5% dilute sulfuric acid at 100 ° C. for 30 minutes, and then thoroughly washed with deionized water at 100 ° C.

  Proton conductivity and swelling rate were evaluated. The results are shown in Table 1. The swelling rate was large and the swelling resistance was poor.

[Example 1]
Potassium carbonate 6.9 g, 9,9-bis (4-hydroxyphenyl) fluorene 14.0 g, 4,4′-difluorobenzophenone 5.2 g, 3.4 g of the compound of formula (m1) obtained in Synthesis Example 1, Polymerization was performed at 190 ° C. in N-methylpyrrolidone (NMP) using 2.5 g of the compound of (m2) and 2.0 g of the compound of formula (m3). During this time, toluene was added as appropriate and water was removed from the polymerization system by an azeotropic method. Purification was performed by reprecipitation with a large amount of water to obtain a polymer having an ionic group. The weight average molecular weight of the obtained polymer was 180,000. The obtained polymer was used as an N-methyl-2-pyrrolidone solution (20% by weight).

  The solution was cast on a glass substrate and dried at 100 ° C. for 4 hours to remove the solvent. Furthermore, it heated up on 200-300 degreeC over 1 hour in nitrogen gas atmosphere, and heat-processed on the conditions heated at 300 degreeC for 10 minutes, Then, it stood to cool. After immersing in 1N hydrochloric acid for 3 days or more to perform proton substitution, it was immersed in a large excess of pure water for 3 days or more and thoroughly washed. A polymer electrolyte membrane was obtained. The proton conductivity and swelling rate of the obtained polymer electrolyte membrane were evaluated. The results are shown in Table 1.

[Comparative Example 2]
6.9 g of potassium carbonate, 14.0 g of 9,9-bis (4-hydroxyphenyl) fluorene, 4.0 g of 4,4′-difluorobenzophenone, and 9.1 g of the compound of the formula (m1) obtained in Synthesis Example 1 The polymerization was carried out at 190 ° C. in N-methylpyrrolidone (NMP). During this time, toluene was added as appropriate and water was removed from the polymerization system by an azeotropic method. Purification was performed by reprecipitation with a large amount of water to obtain a polymer having an ionic group. The weight average molecular weight of the obtained polymer was 180,000, and the ion exchange capacity was the same as that of the polymer of Example 1. The obtained polymer was made into an N-methyl-2-pyrrolidone solution (20% by weight), and a polymer electrolyte membrane was obtained in the same manner as in Example 1. The proton conductivity and swelling rate of the obtained polymer electrolyte membrane were evaluated. The results are shown in Table 1.

[Example 2]
(1) Production of membrane electrode assembly (MEA) A carbon fiber cloth substrate was subjected to a water repellent treatment using a 20% polytetrafluoroethylene (PTFE) suspension, and baked to produce two electrode substrates. .

  On one electrode substrate, an anode electrode catalyst coating solution composed of Pt—Ru-supported carbon and an N-methyl-2-pyrrolidone solution of the polymer electrolyte material obtained in Example 1 was applied and dried. An anode electrode was prepared.

  On the other electrode substrate, a cathode electrode catalyst coating solution comprising Pt-supported carbon and a “Nafion” solution was applied and dried to prepare a cathode electrode.

  The polymer electrolyte membrane obtained in Example 1 was held between an anode electrode and a cathode electrode, and heated and pressed to produce an MEA.

(2) Production of Polymer Electrolyte Fuel Cell The MEA obtained in (1) was sandwiched between cells manufactured by Electrochem, and hydrogen gas was supplied to the anode side and air was supplied to the cathode side to obtain a polymer electrolyte fuel cell. .

The polymer electrolyte fuel cell using the polymer electrolyte membrane of this example showed high output (20 mW / cm ² ) even under low humidification (80 ° C., 30% RH).

[Comparative Example 3]
Using the polymer electrolyte membrane of Comparative Example 2, a membrane electrode assembly and a polymer electrolyte fuel cell were produced in the same manner as in Example 2. The output (6 mW / cm ² ) under low humidification (80 ° C., 30% RH) was smaller than that in Example 2.

  The polymer having an ionic group, the polymer electrolyte material or the polymer electrolyte component of the present invention can be applied to various applications. For example, it can be applied to filtration applications, concentration applications, ion exchange resin applications, various structural material applications, coating material applications, polymer actuator applications, extracorporeal circulation columns, medical applications such as artificial skin, and electrochemical applications. Further, for example, the electrochemical application includes a fuel cell, a redox flow battery, a water electrolysis device, a chloroalkali electrolysis device, and the like. Among these, a fuel cell is particularly preferable. For example, a direct fuel cell using methanol or the like as a fuel. Used.

  As a use of the polymer electrolyte fuel cell of the present invention, a power supply source of a moving body is preferable. In particular, it is used in mobile device retailing, restaurants, transportation, transportation, etc., such as mobile phones, personal computers, PDAs (Portable Digital Assistance), wireless ID readers (RFID readers), video cameras (camcorders), and digital cameras. Electric power for mobile devices such as electric terminals, electric shavers, vacuum cleaners, etc., electric tools, cars, cars such as buses and trucks, motorcycles, electric assist bicycles, electric carts, electric wheelchairs, ships and railways It is preferably used as a supply source.

Claims (13)

A polymer having an ionic group, comprising a partial structure represented by the following formula (A1) and having a weight average molecular weight of 10,000 or more and 5,000,000 or less.

[In Formula (A1), G ¹ represents a substituent selected from a ketone group and a sulfone group. X represents H and any cation. m and n represent an integer of 0 to 4, and 3 ≦ (m + n) ≦ 8. The structure represented by the formula (A1) may be optionally substituted. ] The polymer having an ionic group according to claim 1, wherein G ¹ in the formula (A1) is a ketone group. The polymer having an ionic group according to claim 1 or 2, which has a skeleton containing a repeating unit of the following formula (P1).

^{-Y 11 -Z 11 -Y 21 -Z 21} - (P1)

[In Formula (P1), Y ¹¹ and Y ²¹ each represent O or S. Z ¹¹ represents a divalent group containing an aromatic ring, and Z ¹¹ may be optionally substituted. Z ²¹ represents a group represented by the formula (A1). ] The polymer having an ionic group according to claim 3, wherein Z ¹¹ in the formula (P1) is at least one group selected from the following formulas (B1) to (B3).

[In Formulas (B1) to (B3), Q ¹ represents a substituent selected from a direct bond, a methylene group, a carbonyl group, O and S. Q ² represents a substituent selected from H, a methyl group, and a phenyl group. Q ³ represents a substituent selected from a carbonyl group and a sulfonyl group. Q ⁴ represents a substituent selected from O, S and N—R ¹ . R ¹ here represents a substituent selected from H, an alkyl group, and an aryl group. The structures represented by formulas (B1) to (B3) may be optionally substituted. ] In Formula (B1), Q ¹ is a direct bond, in Formula (B2), Q ² is a phenyl group, in Formula (B3), Q ³ is a carbonyl group, and Q ⁴ is O and N—R. ^The polymer having an ionic group according to claim 4, wherein the polymer is a substituent selected from ¹ . Furthermore, it has the frame | skeleton containing the repeating unit of following formula (P2), The polymer which has an ionic group of any one of Claims 3-5 characterized by the above-mentioned.

^{-Y 12 -Z 12 -Y 22 -Z 22} - (P2)

[In Formula (P2), Y ¹² and Y ²² each represent O or S. Z ¹² represents a divalent group containing an aromatic ring, and Z ¹² may be optionally substituted. Z ²² represents a group represented by the following formula (A2). ]

[In formula (A2), G ² represents a substituent selected from a carbonyl group and a sulfonyl group. X represents H and any cation. The group of formula (A2) may be further optionally substituted. ] The polymer having an ionic group according to any one of claims 1 to 6, wherein the ionic group is a sulfonic acid group or a sulfonimide group. The polymer having an ionic group according to claim 7, wherein the ionic group is a sulfonic acid group. A polymer electrolyte material comprising the polymer having an ionic group according to any one of claims 1 to 8. A polymer electrolyte component comprising the polymer electrolyte material according to claim 9. A membrane electrode assembly comprising the polymer electrolyte component according to claim 10. A polymer electrolyte fuel cell comprising the membrane electrode assembly according to claim 11. The polymer electrolyte fuel cell is a direct fuel cell using at least one selected from an organic compound having 1 to 6 carbon atoms and a mixture thereof with water as a fuel. The polymer electrolyte fuel cell as described.