JP5884360B2 - Polymer electrolyte, polymer electrolyte membrane and solid polymer fuel cell using the same - Google Patents

Description

  The present invention relates to a polymer electrolyte, a polymer electrolyte membrane using the polymer electrolyte, and a solid polymer fuel cell, and more particularly, a polymer electrolyte used in a solid polymer fuel cell, a polymer electrolyte membrane using the polymer electrolyte, and a solid polymer The present invention relates to a polymer fuel cell.

  Solid polymer fuel cells (hereinafter referred to as “PEFC (Polymer Electrolyte Fuel Cell)”) can contribute to reducing the release of environmentally harmful gases, so that fuel cell vehicles and stationary cogeneration Research and development is underway as a power source for mobile phones. In PEFC, a power generation reaction proceeds by proton conduction in the battery. The presence of water is indispensable for proton conduction in the PEFC, and therefore a humidifier is required to advance the power generation reaction of the PEFC. When a fuel cell is applied to a vehicle or the like, since a humidifier is desired to be small from the viewpoint of in-vehicle performance, there is a demand for an electrolyte membrane that allows good proton conduction even under low humidification. Fluorine resin electrolytes typified by Nafion (registered trademark, manufactured by DuPont) and Aciplex (registered trademark, manufactured by Asahi Kasei) are excellent in proton conductivity under low humidification and are widely used in PEFC. is there.

However, since the fluorine-based electrolyte membrane is a polymer material made of fluorine, there is a problem that recyclability is low. Considering the widespread use of fuel cell vehicles, whether fuel cells can be recycled is very important, and the environmental impact of materials that cannot be recycled cannot be ignored.
Furthermore, when a fluorine resin electrolyte is applied alone as an electrolyte membrane, there is a problem that durability is lowered. For these reasons, there is an increasing need for new materials that can substitute for fluororesin electrolytes.

One specific alternative material is a hydrocarbon-based electrolyte, and the development of this hydrocarbon-based electrolyte has been carried out in recent years. Hydrocarbon materials are generally more durable than fluororesin electrolytes and are expected to replace fluororesin electrolytes.
For example, in Patent Document 1, in order to obtain a high proton conductivity with a low humidity by using a hydrocarbon-based electrolyte, a material having a liquid crystal skeleton is used to form a network of sulfonic acid groups, thereby reducing the low humidity. It is described that high proton conductivity can be obtained.

JP 2003-55337 A

  However, the sulfonated liquid crystal polymer material obtained by increasing the molecular weight of the sulfonic acid type liquid crystal monomer material described in Patent Document 1 has a methacrylic skeleton or an acrylic skeleton. For this reason, it may be difficult to improve the performance by thinning the polymer electrolyte membrane. Moreover, since said material has an ester bond, the decomposition reaction by a hydrolysis may advance easily.

  Therefore, the present invention solves the above-mentioned problems, and has a main chain that can be made into a thin film, is excellent in hydrolysis and radical resistance, and has improved power generation performance. An object is to provide a molecular electrolyte membrane and a polymer electrolyte fuel cell.

In order to achieve the above object, a polymer electrolyte according to the present invention, a polymer electrolyte membrane using the polymer electrolyte, and a polymer electrolyte fuel cell are configured as follows.
First polyelectrolyte according to an aspect of the present invention, the chemical general formula _{(1) (A 1, A} 2 represents an alkylene group, B ₁ represents an electron withdrawing group, B ₂ is an electron And Y represents a protonic acid group selected from a sulfonic acid group, a phosphonic acid group, a hydroxyl group, or a carboxyl group, and n represents an integer of 10 to 10,000. It has a unit, the electron withdrawing group is a carbonyl group, wherein the electron donating group is characterized amino group der Rukoto.

According to the polymer electrolyte, the main chain of the polymer electrolyte is changed to a phenylene skeleton. Moreover, in order to improve hydrolysis resistance, the ester site | part is removed. At the same time, in order to improve radical resistance, an electron withdrawing group is introduced and pyridine is introduced into the mesogen.
That is, by changing the main chain from the acrylic skeleton or the methacryl skeleton to the phenylene skeleton, the polymer becomes a rigid skeleton, and the polymer electrolyte can be thinned. Furthermore, even when a polymer electrolyte membrane with a thin polymer electrolyte is used in a fuel cell, the power generation performance can be improved.
Moreover, according to said polymer electrolyte, a monomer can be synthesize | combined easily and it becomes possible to make the polymer electrolyte membrane which consists of the polymer electrolyte flexible. On the other hand, when an electron-donating group is introduced, for example, the electron density of the mesogen moiety becomes high and it is easy to be attacked by radicals, but since a pyridine skeleton having a low electron density is introduced into the skeleton, radical stability is maintained. It becomes possible to do.
The second polymer electrolyte according to aspects of the present invention, the alkylene _{group, - (CH 2) m -} (m is an integer of 1 or more.) Characterized in that it is a.

According to the polymer electrolyte of the above, an alkylene group - (CH ₂₎ m _- and doing, while maintaining the flexibility of the polymer electrolyte membrane comprising the polymer electrolyte, a high acid value polymer electrolyte membrane Can be obtained .

The third polymer electrolyte according to an embodiment of the present invention has the following chemical general formula (2) (X ₁ ) having X ₁ and X ₂ as groups capable of being polymerized with respect to the chemical general formula (1). , X ₂ each independently represents a chlorine atom, a bromine atom, or an iodine atom.).

According to the above polymer electrolyte, since it is formed to contain an ionic material, sufficient mechanical strength that can form a membrane electrode assembly can be obtained even when the polymer electrolyte membrane is thinned. Is possible .
A polymer electrolyte membrane according to an aspect of the present invention is characterized by being formed using the polymer electrolyte according to any one of the first to third aspects.

Since the polymer electrolyte membrane is formed using the polymer electrolyte described above, it is possible to improve the power generation performance.
A solid polymer fuel cell according to an aspect of the present invention is formed using the above polymer electrolyte membrane.
According to the polymer electrolyte fuel cell, the membrane electrode assembly is formed using the polymer electrolyte membrane formed using the polymer electrolyte described above. The power generation performance can be improved.

According to the polymer electrolyte of the present invention, by changing the main chain from an acrylic skeleton or a methacryl skeleton to a phenylene skeleton, the polymer becomes a rigid skeleton, and the polymer electrolyte can be thinned. Furthermore, power generation performance can also be improved when a polymer electrolyte membrane obtained by thinning a polymer electrolyte is used in a fuel cell. Moreover, since the polymer electrolyte of the present invention has an electron-attracting group in addition to pyridine having a low electron density, radical stability can be improved.
Furthermore, a polymer electrolyte fuel cell having high power generation performance can be provided by constituting a polymer electrolyte fuel cell using the above polymer electrolyte membrane.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded sectional view showing a configuration of a single cell 11 of a polymer electrolyte fuel cell equipped with a membrane electrode assembly 12 having electrode catalyst layers formed on both surfaces of a polymer electrolyte membrane 1 of the present invention. It is principal part sectional drawing which shows the structure of the membrane electrode assembly 12 shown in FIG.

Hereinafter, a polymer electrolyte of the present invention, a polymer electrolyte membrane using the polymer electrolyte, and a solid polymer fuel cell will be described in detail with reference to the accompanying drawings.
The present invention is not limited to the embodiments described below, and modifications such as design changes can be added based on the knowledge of the operator, and such modifications can be added. The described embodiments can also be included in the scope of the present invention.

First, with reference to FIG. 1 and FIG. 2, the whole structure of the single cell 11 of the polymer electrolyte fuel cell according to this embodiment will be described.
FIG. 1 is an exploded view showing the structure of a single cell 11 of a polymer electrolyte fuel cell equipped with a membrane electrode assembly 12 having electrode catalyst layers formed on both sides of a polymer electrolyte membrane (polymer electrolyte) 1 of the present invention. It is sectional drawing.

  The single cell 11 of the polymer electrolyte fuel cell shown in FIG. 1 is formed by sandwiching a membrane electrode assembly 12 between two separators 10 that protect the upper and lower portions thereof. An air electrode side gas diffusion layer 4 is formed as a gas diffusion layer between one of the two separators 10 and the membrane electrode assembly 12. Similarly, the fuel electrode side gas diffusion layer 5 is formed as a gas diffusion layer between the other separator and the membrane electrode assembly 12.

In the membrane electrode assembly 12, the air electrode side electrode catalyst layer 2 is formed on the surface of the air electrode side gas diffusion layer 4 of the polymer electrolyte membrane 1. In the membrane electrode assembly 12, the fuel electrode side electrode catalyst layer 3 is formed on the surface of the fuel electrode side gas diffusion layer 5 of the polymer electrolyte membrane 1.
The air electrode 6 that functions as an electrode is formed by the air electrode side electrode catalyst layer 2 and the air electrode side gas diffusion layer 4. Further, the fuel electrode 7 that functions as an electrode is formed by the fuel electrode side electrode catalyst layer 3 and the fuel electrode side gas diffusion layer 5. The load can be driven by connecting an external load (not shown) to the air electrode 6 and the fuel electrode 7.

The separator 10 has a gas flow path 8 formed on one surface as a flow path for gas, and a cooling water flow path 9 formed on the other face as a flow path for cooling water.
FIG. 2 is a cross-sectional view of an essential part showing the configuration of the membrane electrode assembly 12 shown in FIG. In the membrane electrode assembly 12 shown in FIG. 2, the air electrode side electrode catalyst layer 2 is formed on the surface of the polymer electrolyte membrane 1 on the air electrode 6 side. The membrane electrode assembly 12 has the air electrode side electrode catalyst layer 3 formed on the surface of the polymer electrolyte membrane 1 on the fuel electrode 7 side.

A _1, A ₂ in the following chemical formula (1) represents an alkylene group, B ₁ represents an electron withdrawing group, B ₂ represents an electron donating group, Y is a sulfonic acid group, a phosphonic acid A protonic acid group selected from a group, a hydroxyl group, or a carboxyl group, and n is an integer of 10 or more and 10,000 or less.

Then, the above chemical formula (1), a polymer unit represented by the above chemical formula with X _1, X ₂ as a possible polymerization group (2). The polymer electrolyte 1 is obtained by polymerizing an ionic material (hereinafter, referred to as “monomer”) having a polymerizable group represented by the following chemical general formula (2).

[About monomer]
A _1, A ₂ alkylene groups in the above chemical formula (2) selecting, B ₁ is an electron withdrawing group, B ₂ is an electron donating group, Y is a sulfonic acid group, a hydroxyl group, a carboxyl group Each of the protonic acid groups is shown. Further, X ₁ and X ₂ are each independently a chlorine atom, a bromine atom, or an iodine atom. X ₁ and X ₂ may be the same atom or different atoms, but are preferably the same atom.

Here, the group which can be polymerized specifically refers to a group containing X ₁ or X ₂ . The ionic material means a material having a protonic acid group represented by Y.
Alkylene group represented by _A 1, _{A 2} of the above chemical formula (2) in _{the, - (CH 2) m -} (. M is 1 or more is an integer) is preferably, m is Particularly preferred is 3 or 4. When m is 3 or 4, a polymer electrolyte membrane having a high acid value can be obtained while maintaining the flexibility of the polymer electrolyte membrane comprising the polymer electrolyte.

B _{1 in} the chemical general formula (2) is preferably an electron withdrawing group. When B ₁ is an electron withdrawing group, radical stability can be improved. Examples of the electron withdrawing group include a sulfo group, a nitro group, a cyano group, and a carbonyl group. In particular, when B ₁ is a carbonyl group, the monomer represented by the general formula (2) is easily synthesized. And radical stability can be further improved.

B _{2 in} the chemical general formula (2) is preferably an electron donating group. As the electron donating property, an amino group is particularly preferable. When B ₂ is an amino group, the monomer represented by the general chemical formula (2) can be easily synthesized, and the polymer electrolyte membrane made of the polymer electrolyte can be made flexible. On the other hand, when an electron-donating group is introduced, for example, the electron density of the mesogen moiety increases and it is easily attacked by radicals. However, since a pyridine skeleton having a low electron density is introduced into the skeleton, radical stability is maintained. be able to.
The ion exchange capacity of the polymer electrolyte 1 is particularly preferably 2.1 meq / g or more and 2.4 meq / g or less from the viewpoint of the performance of the polymer electrolyte membrane as described above.

[Manufacturing method of monomer]
The above manufacturing method of a monomer chemical formula (2) is not particularly limited, for example, _{A 1} is _{- (CH 2) 4 -,} B 1 is a carbonyl group, _{B 2} is an amino group, _{A 2} is ( When —CH ₂ ) ₃ — and Y are sulfonic acid groups, they can be synthesized as follows. Even when A ₁ , B ₁ , A ₂ , and Y are not the above-described configuration, the monomer of the above general formula (2) is produced by combining the following synthesis method and a known synthesis method. can do.
First. A compound (A) represented by the following chemical general formula (3) is prepared.

Here, X ₁ and X ₂ are each a chlorine atom, a bromine atom or an iodine atom. From the viewpoint of reaction efficiency, 1,4-dichlorobenzene is preferable.
Next, the compound (C) represented by the following chemical general formula (5) is reacted with the compound (B) represented by the following chemical general formula (4). Can be obtained.

Here, X ₁ in the above formula is either a chlorine atom, a bromine atom or an iodine atom. From the viewpoint of reaction efficiency, X ₁ is preferably a chlorine atom.

The reaction conditions at this time are not particularly limited. However, the reaction temperature is preferably 25 ° C. to 80 ° C., more preferably 40 ° C. to 70 ° C., and the reaction time is preferably 8 hours to 48 hours, more preferably 16 hours to 32 hours. The reaction is carried out under the reaction conditions.
Moreover, since the pressure at the time of performing said reaction is not specifically limited, it may be under pressure, normal pressure (atmosphere), or pressure reduction, and should just be set suitably. However, the reaction is preferably performed using an inert gas atmosphere such as argon gas or nitrogen gas.
The compound (B) is preferably 50 mol% or more and 100 mol% or less, and preferably 80 mol% or more and 100 mol% or less, relative to 100 mol% of the compound (A).

Moreover, what is necessary is just a Lewis' acid catalyst as a catalyst used when performing said reaction. An example of a Lewis acid catalyst is anhydrous aluminum chloride.
The catalyst is preferably 100 mol% or more and 200 mol% or less, more preferably 100 mol% or more and 150 mol% or less, relative to 100 mol% or more of the compound (A).
Next, the compound (D) represented by the following chemical formula (6) can be obtained by reacting the above compound (C) with thionyl chloride.

The reaction conditions at this time are not particularly limited, but the reaction temperature is preferably 25 ° C. or higher and 80 ° C. or lower, more preferably 40 ° C. or higher and 60 ° C. or lower, and the reaction time is preferably 1 hour or longer and 10 ° C. The reaction is performed for a time or less, more preferably 2 hours or more and 5 hours or less.
The reaction is desirably performed in a nitrogen atmosphere from the viewpoint of reaction efficiency.
The reaction solvent used in the above reaction is preferably a good solvent. For example, tetrahydrofuran, cyclohexanone, dimethyl sulfoxide, N, N-dimethylformamide, N, N-dimethylacetamide, N, N-dimethylacetamide, N -Methyl-2-pyrrolidone, γ-butyrolactone, N, N-dimethylimidazolinone and the like.
Next, the compound (E) represented by the following chemical general formula (7) is reacted with propane sultone.

  And as a result of making said 2 compound react, the compound (F) represented by following chemical general formula (8) can be obtained.

  The reaction conditions at this time are not particularly limited, but the reaction temperature is preferably 25 ° C. or higher and 80 ° C. or lower. The reaction time is preferably 10 hours to 48 hours. Note that the atmosphere in which the reaction is performed may be an air atmosphere or a nitrogen atmosphere.

The reaction solvent used in carrying out this reaction is desirably a good solvent, and more preferably an alcohol solvent. Specific examples of the reaction solvent include ethanol, methanol, propanol, and 1-butanol.
Said monomer can be obtained by making said compound (D) and said compound (F) react. Specifically, in the chemical general formula (2), A ₁ is — (CH ₂ ) ₄ —, B ₁ is a carbonyl group, B ₂ is an ether group, and A ₂ is — (CH ₂ ) ₃ —. , Y is a sulfonic acid group.

The reaction conditions at this time are not particularly limited, but the reaction temperature is preferably 25 ° C. or more and 80 ° C. or less, more preferably 40 ° C. or more and 70 ° C. or less, the reaction time is preferably 8 hours or more and 48 hours or less, More preferably, the reaction is performed for 16 hours or more and 32 hours or less.
The pressure during the reaction is not particularly limited, and may be either under pressure, under normal pressure (atmospheric pressure), or under reduced pressure, and may be appropriately set depending on circumstances, but may be under normal pressure. preferable.

The atmosphere in which the reaction is performed is not particularly limited, but it is preferably performed in an inert gas atmosphere such as argon gas or nitrogen gas.
The compound (D) is preferably 50 mol% or more and 100 mol% or less, and more preferably 80 mol% or more and 100 mol% or less with respect to 100 mol% of the compound (F).

  The catalyst used at this time may be a Lewis acid catalyst, and an example of the Lewis acid catalyst is anhydrous aluminum chloride. The catalyst is preferably 100 mol% or more and 200 mol% or less, more preferably 100 mol% or more and 150 mol% or less with respect to 100 mol% of the compound (D).

[Polymer electrolyte production method]
The polymerization of the monomer is not particularly limited, but it is preferable to react in the presence of a specific catalyst. The catalyst used in this case is a catalyst system containing a transition metal compound. The catalyst system includes a ligand component, a transition metal complex coordinated with the ligand, and a reducing agent as essential components. A salt may be added to increase the polymerization rate.

  Examples of the ligand component include triphenylphosphine, 2,2′-bipyridine, 1,5-cyclooctadiene, 1,3-bis (diphenylphosphino) propane, and the like. Of these, triphenylphosphine and 2,2'-bipyridine are preferred. Only one type of the above-mentioned ligand component may be used alone, or two or more types may be used in combination. The ligand component is preferably 1 mol% or less and 100 mol% or less, more preferably 1 mol% or more and 20 mol% or less with respect to 100 mol% of the monomer.

  Examples of transition metal complexes in which a ligand is coordinated include nickel chloride bis (triphenylphosphine), nickel bromide bis (triphenylphosphine), nickel iodide bis (triphenylphosphine), and nickel nitrate bis (tri Phenylphosphine), nickel chloride (2,2-bipyridine), nickel bromide (2,2-bipyridine), bis (1,5-cyclooctadiene) nickel, tetrakis (triphenylphosphine) nickel, tetrakis (triphenylphos) Phyto) nickel or tetrakis (triphenylphosphine) palladium. Of these, nickel chloride bis (triphenylphosphine) and nickel chloride (2,2-bipyridine) are preferred. The transition metal complex is preferably 1 mol% or more and 100 mol% or less, and more preferably 1 mol% or more and 20 mol% or less with respect to 100 mol% of the monomer.

  Examples of the reducing agent that can be used in the above catalyst system include iron, zinc, manganese, aluminum, magnesium, sodium, and calcium. Of these, zinc, magnesium and manganese are preferred. These reducing agents can be used after being more activated by bringing them into contact with an acid such as an organic acid. The reducing agent is preferably 1 mol or more and 100 mol% or less, and preferably 10 mol% or more and 30 mol% or less with respect to 100 mol% of the monomer.

  Examples of salts that can be used in the above catalyst system include sodium compounds such as sodium fluoride, sodium chloride, sodium bromide, sodium iodide, and sodium sulfate; potassium fluoride, potassium chloride, potassium bromide, iodine Potassium compounds such as potassium iodide and potassium sulfate; ammonium compounds such as tetraethylammonium fluoride, tetraethylammonium chloride, tetraethylammonium bromide, tetraethylammonium iodide, and tetraethylammonium sulfate. Of these, sodium bromide, sodium iodide, potassium bromide, tetraethylammonium bromide, and tetraethylammonium iodide are preferred. The salt is preferably 1 mol% or more and 100 mol% or less, and preferably 10 mol% or more and 30 mol% or less with respect to 100 mol% of the monomer.

  Examples of the solvent used in the polymerization include tetrahydrofuran, cyclohexanone, dimethyl sulfoxide, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, γ-butyrolactone, N, N-dimethylimidazolidinone is preferred. These polymerization solvents are preferably used after sufficiently dried.

  The polymerization temperature and the polymerization time during the polymerization are not particularly limited, and may be appropriately set depending on the molecular weight, the polymerization concentration, and the like. For example, when it is intended to obtain a polymer having a weight average molecular weight of 100,000 or more and 500,000 or less, the polymerization temperature is preferably 25 ° C. or more and 80 ° C. or less, more preferably 40 ° C. or more and 70 ° C. from the viewpoint of reaction efficiency. Hereinafter, the polymerization is performed in a polymerization time of preferably 8 hours to 40 hours, more preferably 16 hours to 32 hours.

The polymerization pressure at the time of polymerization is not particularly limited, and may be any of under pressure, normal pressure (atmosphere), and reduced pressure, and may be appropriately set depending on circumstances, but is preferably under normal pressure.
The degree of polymerization of the monomer, that is, n in the chemical general formula (1) is preferably 10 or more and 10,000 or less, and more preferably 1000 or more and 10,000 or less. When n is in the above range, the polymer electrolyte can be easily dissolved in the solvent, and the film formability can be improved.

[Production method of polymer electrolyte membrane]
A method for producing a polymer electrolyte membrane using the polymer electrolyte thus obtained is not particularly limited. For example, the polyphenylene electrolyte of the present invention is dissolved in a solvent to form a solution, and then cast by casting. Examples thereof include a method of coating on a substrate and forming it into a film, a method of applying and forming a film using an applicator controlled to a predetermined gap, and a method of forming a film using a die coater.

  In film formation, the viscosity of the solution is preferably 10 mPa · s or more and 10,000 mPa · s or less, and more preferably 10 mPa · s or more and 1000 mPa · s or less. Within the above range, the residual amount of the solvent is small, and the probability that a large amount of bubbles are generated when the solution is dried is low, and the thickness unevenness can be reduced by the leveling effect, so that stable proton conductivity is achieved. Is secured.

In this case, the concentration of the polymer electrolyte is usually 2.5% by weight or more and 50% by weight or less, preferably 7% by weight or more and 25% by weight or less, although it depends on the molecular weight. Within the above range, the film formability is excellent.
Examples of the solvent used in this case include N-methyl-2-pyrrolidone, N, N-dimethylformamide, γ-butyllactone, N, N-dimethylacetamide, dimethyl sulfoxide, dimethylurea, dimethylimidazolidinone. And aprotic polar solvents such as methanol, ethanol, propyl alcohol, iso-propyl alcohol, sec-butyl alcohol and tert-butyl alcohol, and ketone solvents such as acetone, methyl ethyl ketone and cyclohexanone. These solvents may be used alone or in combination of two or more. Moreover, you may use what added water to these solvents.
Moreover, the polymer electrolyte solution whose viscosity has been adjusted is cast on a substrate, for example. Examples of the base material to be cast include metal materials, glass, ceramics, and plastics. The shape of the substrate is not particularly limited.
Furthermore, the coating film formed on the substrate is preferably heated at 25 ° C. or higher and 140 ° C. or lower and 0.1 hour or longer and 24 hours or shorter to form the polymer electrolyte membrane of the present invention.

[About polymer electrolyte fuel cells]
A polymer electrolyte fuel cell generally includes a polymer electrolyte membrane, a membrane electrode assembly comprising an air electrode side electrode catalyst layer and a fuel electrode side catalyst layer provided on both sides of the polymer electrolyte membrane, and an air electrode side electrode. The air electrode side gas diffusion layer and the fuel electrode side gas diffusion layer disposed to face the catalyst layer and the fuel electrode side electrode catalyst layer, and a separator sandwiching them.
The polymer electrolyte of the present invention has sufficient mechanical strength even when it is thinned, and can improve hydrolysis resistance and radical stability. Therefore, the polymer electrolyte membrane constituting the solid polymer fuel cell is used. It can be used as a material. Moreover, an air electrode side electrode catalyst layer or a fuel electrode side electrode catalyst layer can be formed together with the conductive material and the catalyst material.
Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples. However, the present invention is not limited to the examples and comparative examples described below.

[Example]
<Synthesis of Compound (C-1)>
Prepare 14.6 g (0.1 mol) of 1,4-dichlorobenzene and 13.6 g (0.1 mol) of 1-chlorohexanoic acid, add 14.6 g (0.11 mol) of aluminum chloride, and add nitrogen atmosphere. Under stirring for 1 hour. The organic component of the reaction solution was recovered by extraction and recrystallized using cyclohexane. After drying, a compound (C-1) represented by the following chemical general formula (9) was obtained.

<Synthesis of Compound (D-1)>
Under a nitrogen atmosphere, 118.9 g (1 mol) of thionyl chloride and 5 ml of dimethylformamide were added to 50 g (0.2 mol) of the obtained compound (C-1), followed by heating and stirring at 45 ° C. for 4 hours. Compound (D-1) represented by the general chemical formula (10) was obtained.

<Synthesis of Compound (F)>
Under a nitrogen atmosphere, 141.7 g (1.16 mol) of propane sultone was added to 49.4 g (0.29 mol) of 2-amino-5-phenylpyridine (compound (E) represented by the above chemical formula (7)). Then, 20 g (0.5 mol) of sodium hydroxide and 200 ml of methanol were added and stirred for 48 hours.
Then, it reprecipitated with diethyl ether and filtered. The filtrate was washed with hydrochloric acid to obtain the compound (F) represented by the above chemical general formula (8).
<Synthesis of monomer>
Under a nitrogen atmosphere, 10 g (0.038 mol) of the compound (D-1), 11.1 g (0.038 mol) of the compound (F), 5.56 g (0.042 mol) of aluminum chloride, and 30 ml of dimethylformamide were added. In addition, the mixture was stirred at 60 ° C. for 1 hour to obtain a monomer of an example represented by the following chemical general formula (11).

<Synthesis of polymer electrolyte>
Under a nitrogen atmosphere, 7.79 g (14.58 mmol) of the monomer of the example, 1.493 g (5.692 mmol) of triphenylphosphine, 0.293 g (1.953 mmol) of sodium iodide, and 1.281 g (19.19) of zinc. 59 mmol), 0.311 g (0.475 mmol) of bis (triphenylphosphine) nickel (II) dichloride is added. Furthermore, 20 ml of dimethylformamide was added as a solvent, and the mixture was stirred at 60 ° C. for 24 hours to obtain a polymer electrolyte of an example represented by the following chemical general formula (12).

[Comparative example]
<Synthesis of 9-bromo-1-decene>
To a 500 ml Erlenmeyer flask, 100 ml of benzene and 1.0 g of pyridine were added to dissolve 25 g (0.16 mol) of 9-decen-1-ol. Next, 100 ml of a benzene solution in which 43.2 g (0.16 mol) of phosphorus tribromide was dissolved was slowly added dropwise under ice cooling, followed by stirring at room temperature for 18 hours. Thereafter, the reaction solution was poured into ice water and extracted with 300 ml of diethyl ether. The ether-benzene mixture obtained here was dehydrated overnight with anhydrous sodium sulfate. Sodium sulfate was removed by suction filtration, ether-benzene was removed under reduced pressure, and the residue was distilled under reduced pressure to obtain the desired product 9-bromo-1-decene.

<Synthesis of 4- (9-decenyloxyphenyl) phenol>
Sodium hydroxide 0.08 mol (3.40 g) was dissolved in 100 ml of ethanol. This solution was added little by little to 100 mL ethanol in which 0.08 mol (14.9 g) of 4,4′-biphenol was dissolved, and ethanol was removed under reduced pressure. The residue was dissolved in 150 mL DMF by heating under a nitrogen stream (solution A). 0.072 mol (15.8 g) of 9-bromo-1-decene prepared above and 0.1 g of phenothiazine were dissolved in 30 mL of DMF (solution B). Liquid B was added to liquid A over about 30 minutes while stirring well in a nitrogen atmosphere, and reacted at 40 ° C. for 24 hours. After completion of the reaction, the reaction solution was cooled, washed with 300 mL of 10% cold dilute hydrochloric acid, extracted with 300 mL of ether, and then washed with 100 mL of cold distilled water. The ether layer is dehydrated with anhydrous sodium sulfate overnight. Sodium sulfate is removed by filtration and ether is removed under reduced pressure. 300 mL of hexane is added to the residue, and a precipitate is obtained by filtration. Next, 200 mL of benzene was added, and the benzene-soluble part was purified by column chromatography using benzene to obtain sulfonated 4- (9-decenyloxyphenyl) phenol.

<Synthesis of 3- [6- (9-decenyloxy) biphenyloxy] propylsulfonic acid>
In 30 mL of N, N-dimethylformamide, 0.05 g of phenothiazine, which is a polymerization inhibitor, was dissolved. There, 1,8-diazabicyclo [5,4,0] -7-undecene (DBU) 0.008 mol (1.22 g) and 4- (9-decenyloxyphenyl) phenol 0.002 mol (0.65 g) ), 0.008 mol (1.32 g) of sodium 3-bromopropanesulfonate was dissolved and stirred at 50 ° C. for 48 hours under a nitrogen atmosphere. After completion of the reaction, diethyl ether with concentrated solvent was added and filtered to obtain a precipitate. Next, the precipitate was washed well with distilled water. Next, after the washed precipitate was stirred in 6 mol / L HCl for 24 hours, the precipitate was obtained by a centrifuge, and this precipitate was washed with diethyl ether and dried to obtain a monomer of Comparative Example 3- [6- (9-decenyloxy) biphenyloxy] propylsulfonic acid was obtained.

<Molecularization of 3- [6- (9-decenyloxy) biphenyloxy] propylsulfonic acid>
Under a nitrogen atmosphere, 488 mg (1 mmol) of 3- [6- (9-decenyloxy) biphenyloxy] propylsulfonic acid, 6.6 mg (0.04 mmol) of AIBN as an initiator were added, and 4.7 ml of dimethyl sulfoxide was added. It was. Then, it polymerized by heat polymerization at 60 ° C. for 60 hours. Then, it reprecipitated with acetone and obtained 3- [6- (9-decenyloxy) biphenyloxy] propylsulfonic acid polymer which is a polymer electrolyte of a comparative example.

[Polymer electrolyte deposition]
The polymer electrolytes of Examples and Comparative Examples were dissolved in dimethyl sulfoxide, and then cast into glass, followed by vacuum drying at 45 ° C. for 12 hours, 80 ° C. for 12 hours, and 80 ° C. for 1 hour. An example polymer electrolyte membrane was obtained.
[Evaluation]
<Thinning>
The polymer electrolyte membrane of the example had a mechanical strength that can produce a membrane electrode assembly even if it was made thinner than the polymer electrolyte membrane of the comparative example.
<Fenton test>
Further, the polymer electrolyte membranes of Examples and Comparative Examples were immersed in 60 ° C., 3% hydrogen peroxide aqueous solution, and 4 ppm Fe ²⁺ . As a result, it was confirmed that the polymer electrolyte membrane of the example had higher durability than the polymer electrolyte membrane of the comparative example.

  The present invention relates to a polymer electrolyte fuel cell used as a power source for automobiles such as electric vehicles and fuel cell vehicles, mobile devices such as notebook computers, mobile phones and personal digital assistants, and power generators for home use. It can be used for a molecular electrolyte membrane.

1 ... Polymer electrolyte membrane (Polymer electrolyte)
2 …… Air electrode side electrode catalyst layer 3 …… Fuel electrode side electrode catalyst layer 4 …… Air electrode side gas diffusion layer 5 …… Fuel electrode side gas diffusion layer 6 …… Air electrode 7 …… Fuel electrode 8 …… Gas Channel 9 ... Cooling water channel 10 ... Separator 11 ... Single cell of polymer electrolyte fuel cell 12 ... Membrane electrode assembly

Claims (5)

Following chemical formula _{(1) (A 1, A} 2 represents an alkylene group, B ₁ represents an electron withdrawing group, B ₂ represents an electron donating group, Y is a sulfonic acid group, a phosphonic acid group, a hydroxyl group or a protonic acid group selected from carboxyl group,, n will have a polymer unit represented by that.) and 10 to 10,000 integer,
It said electron withdrawing group is a carbonyl group, wherein the electron donating group of the polymer electrolyte, wherein the amino group der Rukoto.

The alkylene _{group, - (CH 2) m -} (. M is the integer of 1 or more) polymer electrolyte according to claim 1, characterized in that a. With respect to the chemical general formula (1), the following chemical general formula (2) having X ₁ and X ₂ as groups capable of being polymerized (X ₁ and X ₂ are each independently a chlorine atom, a bromine atom, Or an iodine atom.) The polymer electrolyte according to claim 1 or 2 , wherein the polymer electrolyte is formed by including an ionic material represented by the following formula.

A polymer electrolyte membrane formed using the polymer electrolyte according to any one of claims 1 to 3 . A solid polymer fuel cell, comprising the polymer electrolyte membrane according to claim 4 .

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