JP4887686B2 - POLYMER ELECTROLYTE MEMBRANE AND METHOD FOR PRODUCING THE SAME - Google Patents

Description

The present invention relates to a polymer electrolyte membrane and a method for producing the same, and more particularly to a method for producing a hydrocarbon-based polymer electrolyte membrane having a strong acid group or a super strong acid group.

The present invention relates to a polymer electrolyte membrane used for a fuel cell, an ion exchange membrane and the like and a method for producing the same.

In recent years, as a response to environmental problems, expectations for fuel cells have greatly increased. In particular, polymer fuel cells using proton-conducting polymer electrolyte membranes can operate at low temperatures and are small in size. Expected from the possibility of weight reduction. As polymer electrolytes for polymer fuel cells, for example, super strong acid group-containing fluorine-based polymers represented by Nafion (registered trademark of Nafion, DuPont, the same applies hereinafter) are known.

The aromatic hydrocarbon polymer electrolyte membrane based on a cheaper non-fluorine polymer has been studied to solve the problem that the fluoropolymer containing super strong acid group is expensive and the alcohol permeability is large. , Many polyimides, polyethers, polyarylenes, etc. have already been proposed (Non-Patent Document 1). For example, as a polyethersulfone-based polymer electrolyte membrane, Japanese Patent Application Laid-Open No. 10-215943 (Patent Document 1), Japanese Patent Application Laid-Open No. 10-45913 (Patent Document 2), Japanese Patent Application Laid-Open No. 11-116679 (Patent Document). 3) discloses a sulfonated polyethersulfone polymer electrolyte membrane. Further, JP-A-11-67224 (Patent Document 4) discloses a membrane / electrode assembly using a sulfonated polyethersulfone-based polymer electrolyte membrane. Japanese Patent Application Laid-Open No. 2003-31232 (Patent Document 5) discloses a polyethersulfone block copolymer with improved humidity dependency of proton conductivity. In Japanese Patent Application Laid-Open No. 2005-112985 (Patent Document 6), a polyarylene-based electrolyte membrane is used. In Japanese Patent Publication No. 2003-503510 (Patent Document 7), a polyetherketone-based electrolyte membrane and a polyethersulfone-based electrolyte membrane are used. Japanese Patent Publication No. 2000-510511 (Patent Document 8) discloses a polyimide electrolyte membrane.

These polymer electrolyte membranes are industrially produced by continuously casting a polymer electrolyte solution on a support, evaporating the solvent until it becomes a self-supporting membrane by heating, and the self-supporting membrane from the support. It is manufactured by the method of peeling. As the support at this time, a metal belt such as stainless steel is generally used. However, a polymer electrolyte membrane having a strong acid group or a super strong acid group is not easy to peel off the self-supporting membrane from a metal belt such as stainless steel, and may be torn or damaged during peeling. Use of phosphate ester and / or salt of phosphate ester and amine as a release agent is added to a solution of polyamic acid, which is a precursor of polyimide, in JP-A-60-244507 (Patent Document 9). Although a method has been disclosed, there has been no description regarding the production of a polymer electrolyte membrane containing a strong acid group such as sulfonic acid or phosphoric acid or a super strong acid group such as fluorinated alkylsulfonic acid.

MA Hickner et al, Chem. Rev., vol.104, p.4587-4612 (2004) Japanese Patent Laid-Open No. 10-21944 Japanese Patent Laid-Open No. 10-45913 Japanese Patent Laid-Open No. 11-116679 JP-A-11-67224 Japanese Patent Laid-Open No. 2003-3232 JP-A-2005-112985 Special table 2003-503510 gazette JP 2000-510511 A JP-A-60-244507

An object of the present invention is to provide a polymer electrolyte membrane in which a self-supporting membrane can be easily detached from a support such as a metal belt such as stainless steel when a membrane made of a polymer electrolyte having a strong acid group or a super strong acid group is produced. It is in providing the manufacturing method of.

The present invention relates to a method for producing a polymer electrolyte membrane having a strong acid group or a super strong acid group by a casting method, wherein

［式中、R¹は水素原子または炭素数が６から１８のアルキル基または化学式２

[Wherein R ¹ represents a hydrogen atom, an alkyl group having 6 to 18 carbon atoms, or a chemical formula 2

（式中、R³は炭素数が５から１８のアルキル基を示し、ｍは２から３０の整数を示す。）
で示される基を表し、R²は炭素数が６から１８のアルキル基または化学式２で示される基を表す。]
で示されるリン酸エステル、および／または、化学式３

(In the formula, R ³ represents an alkyl group having 5 to 18 carbon atoms, and m represents an integer of 2 to 30.)
R ² represents an alkyl group having 6 to 18 carbon atoms or a group represented by Chemical Formula 2. ]
And / or chemical formula 3

［式中、R⁴からR⁶は水素原子、ヒドロオキシエチル基または炭素数が１から１２のアルキル基を表す。］
で示されるアミンと化学式１のリン酸エステルとの塩を０．０００５から２重量部含有する高分子電解質溶液を支持体上に流延し、加熱して自己支持性膜になるまで溶剤を蒸発させ、支持体から自己支持性膜を剥離することを特徴とする高分子電解質膜の製造方法に関する。

[Wherein R ⁴ to R ⁶ represent a hydrogen atom, a hydroxyethyl group or an alkyl group having 1 to 12 carbon atoms. ]
A polyelectrolyte solution containing 0.0005 to 2 parts by weight of a salt of an amine represented by Formula 1 and a phosphate ester of Formula 1 is cast on a support and heated to evaporate the solvent until a self-supporting membrane is obtained. And a method for producing a polymer electrolyte membrane, wherein the self-supporting membrane is peeled from the support.

  The present invention also provides a polymer electrolyte characterized in that the polymer electrolyte membrane obtained by the above production method is further subjected to an acid aqueous solution treatment or an alkali aqueous solution treatment and then an acid aqueous solution treatment. The present invention relates to a film manufacturing method.

  The present invention also relates to a method for producing a polymer electrolyte membrane, wherein the polymer electrolyte is a sulfonated hydrocarbon-based polymer electrolyte.

  The present invention also relates to a method for producing a polymer electrolyte membrane, wherein the hydrocarbon-based polymer electrolyte is an aromatic polymer electrolyte having an aromatic ring in the main chain.

  In the present invention, the aromatic polymer electrolyte is represented by the chemical formula 4

［式中、Ar¹、Ar²は、芳香族基であり、Z¹は、酸素原子を示す。］
で表される構造単位を有する芳香族ポリエーテルであることを特徴とする高分子電解質膜の製造方法に関する。

[Wherein Ar ¹ and Ar ² are aromatic groups, and Z ¹ represents an oxygen atom. ]
It is related with the manufacturing method of the polymer electrolyte membrane characterized by being an aromatic polyether which has a structural unit represented by these.

The present invention also relates to a method for producing a polymer electrolyte membrane, wherein the polymer electrolyte is a composition of a polymer electrolyte having a sulfonic acid group and a polymer having no sulfonic acid group.

The present invention also provides a method for producing a polymer electrolyte membrane, wherein the polymer electrolyte is a block copolymer comprising a hydrophilic segment having a sulfonic acid group and a hydrophobic segment not having a sulfonic acid group About.

The present invention also relates to a polymer electrolyte membrane produced by the method for producing a polymer electrolyte membrane.

As a result of intensive studies on the above-mentioned problems, the present researchers cast a solution obtained by adding a phosphate ester and / or a salt of phosphate ester and amine to a polyelectrolyte solution, and heating the support. By drying, the self-supporting membrane was easily peeled off from the support, and it was found that a polymer electrolyte membrane could be continuously produced, and the present invention was achieved.

The phosphate ester used in the present invention has the chemical formula 1

［式中、R¹は水素原子または炭素数が６から１８のアルキル基または化学式２

[Wherein R ¹ represents a hydrogen atom, an alkyl group having 6 to 18 carbon atoms, or a chemical formula 2

（式中、R³は炭素数が５から１８のアルキル基を示し、ｍは２から３０の整数を示す。）
で示される基を表し、R²は炭素数が６から１８のアルキル基または化学式２で示される基を表す。]
で示されるリン酸エステルであり、例えば、モノカプロイルリン酸エステル、モノオクチルリン酸エステル、モノカプリルリン酸エステル、モノラウリルリン酸エステル、モノミリスチルリン酸エステル、モノセチルリン酸エステル、モノステアリルリン酸エステル、テトラエチレングリコールモノネオペンチルエーテルのモノリン酸エステル、トリエチレングリコールモノトリデシルエーテルのモノリン酸エステル、テトラエチレングリコールモノラウリルエーテルのモノリン酸エステル、ジエチレングリコールモノステアリルエーテルのモノリン酸エステル、ジカプロイルリン酸エステル、ジオクチルリン酸エステル、ジカプリルリン酸エステル、ジラウリルリン酸エステル、ジミリスチルリン酸エステル、ジセチルリン酸エステル、ジステアリルリン酸エステル、テトラエチレングリコールモノネオペンチルエーテルのジリン酸エステル、トリエチレングリコールモノトリデシルエーテルのジリン酸エステル、テトラエチレングリコールモノラウリルエーテルのジリン酸エステル、ジエチレングリコールモノステアリルエーテルのジリン酸エステルなどを挙げることができる。

(In the formula, R ³ represents an alkyl group having 5 to 18 carbon atoms, and m represents an integer of 2 to 30.)
R ² represents an alkyl group having 6 to 18 carbon atoms or a group represented by Chemical Formula 2. ]
For example, monocaproyl phosphate, monooctyl phosphate, monocapryl phosphate, monolauryl phosphate, monomyristyl phosphate, monocetyl phosphate, monostearyl phosphate Ester, monophosphate ester of tetraethylene glycol mononeopentyl ether, monophosphate ester of triethylene glycol monotridecyl ether, monophosphate ester of tetraethylene glycol monolauryl ether, monophosphate ester of diethylene glycol monostearyl ether, dicaproyl phosphate ester, Dioctyl phosphate, dicapryl phosphate, dilauryl phosphate, dimyristyl phosphate, dicetyl phosphate, di Tearyl phosphate ester, tetraethylene glycol mononeopentyl ether diphosphate ester, triethylene glycol monotridecyl ether diphosphate ester, tetraethylene glycol monolauryl ether diphosphate ester, diethylene glycol monostearyl ether diphosphate ester, etc. be able to.

The phosphate ester and amine salt used in the present invention are the above-mentioned phosphate ester, chemical formula 3

［式中、R⁴からR⁶は水素原子、ヒドロオキシエチル基または炭素数が１から１２のアルキル基を表す。］
で示されるアミンとの塩である。化学式３で示されるアミンは、例えば、アンモニア、モノメチルアミン、モノエチルアミン、モノプロピルアミン、モノブチルアミン、モノヘキシルアミン、モノオクチルアミン、モノラウリルアミン、ジメチルアミン、ジエチルアミン、ジプロピルアミン、ジブチルアミン、ジヘキシルアミン、ジオクチルアミン、ジラウリルアミン、トリメチルアミン、トリエチルアミン、トリプロピルアミン、トリブチルアミン、トリヘキシルアミン、トリオクチルアミン、トリラウリルアミン、モノエタノールアミン、ジエタノールアミン、トリエタノールアミンなどを挙げることができる。
前記のようなアルキルリン酸エステル塩としては、市販の物を用いても良く、例えば、中京油脂製の「セパール３２８」「セパール３６５」 ，「セパール３８０」 ，「セパール４４０」 ，「セパール４４１」 、「セパール５１７」 ，「セパール５２１」（以上、商品名）などを挙げることができる。

[Wherein R ⁴ to R ⁶ represent a hydrogen atom, a hydroxyethyl group or an alkyl group having 1 to 12 carbon atoms. ]
It is a salt with amine shown by these. Examples of the amine represented by Chemical Formula 3 include ammonia, monomethylamine, monoethylamine, monopropylamine, monobutylamine, monohexylamine, monooctylamine, monolaurylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, and dihexyl. Examples include amine, dioctylamine, dilaurylamine, trimethylamine, triethylamine, tripropylamine, tributylamine, trihexylamine, trioctylamine, trilaurylamine, monoethanolamine, diethanolamine, and triethanolamine.
As the alkyl phosphate ester salt as described above, commercially available products may be used. For example, “Separ 328”, “Separ 365”, “Separ 380”, “Separ 440”, “Separ 441” manufactured by Chukyo Yushi Co., Ltd. , “Separ 517”, “Separ 521” (above, trade name), and the like.

The amine salt of phosphate ester and / or phosphate ester is 0.001 to 2 parts by weight, preferably 0.002 to 1.5 parts by weight, and more preferably 0.001 to 100 parts by weight of the polymer electrolyte. 003 to 1.0 parts by weight are added. If the added amount is less than 0.001 part by weight, there is no effect, while if it is more than 2 parts by weight, the effect is not changed.

The polymer electrolyte of the present invention has a strong acid group such as a sulfonic acid group and a phosphoric acid group, or a super strong acid group such as a sulfonic acid group bonded to a fluorinated alkyl or aryl fluoride group. Examples thereof include a hydrogen polymer, an aliphatic polymer in which a hydrogen atom is substituted with a fluorine atom, and an aromatic polymer having an aromatic ring in the main chain.

  Examples of such a polymer include sulfonic acid groups described in, for example, polystyrene sulfonic acid, polyvinyl benzyl sulfonic acid, JP-T 2002-509152, European Polymer Journal, Vol. 36, 61 (2001). Contains styrene- (ethylene-butylene) -styrene triblock copolymer and styrene- (ethylene-propylene) block copolymer, Macromolecules, Vol. 28, 8702 (1995) and European Polymer Journal, Vol. 36, 61 ( 2001)), a styrene- (ethylene-butylene) -styrene triblock copolymer or a styrene- (ethylene-propylene) block copolymer containing a carboxylic acid group, and JP-A-2000-11755. Strong polymer containing polystyrene polymers such as polystyrene containing phosphonic acid groups as described, polyacrylic Strong acid group-containing vinyl polymers such as acid, polymethacrylic acid, and polyvinyl sulfonic acid, and perfluoro polymers having super strong acid groups such as Nafion (registered trademark), Aciplex (registered trademark), and Flemion (registered trademark) And a polymer having an aliphatic main chain.

Aromatic polymer electrolytes such as polyethersulfone, polysulfone, polyetherketone, polyetheretherketone, polyetherketoneketone, polyimide, polyphenyleneoxide, polyarylene, polyphenylenesulfide, etc. containing strong acid groups or superacid groups Can also be mentioned. For example, JP-A 61-43630, J. Membr. Sci., Vol. 83, 211 (1993), J. Polym. Sci., Part A, Polym. Chem., Vol. 34, 2421 (1996). Fragrance containing a sulfonic acid group as described in J. Polym. Sci., Part A, Polym. Chem., Vol. 31, 853 (1993), USP2001 / 0021764A1, and JP-A-2003-32322. Group polyethersulfone, JP-A-57-25328, JP-A-57-25328, JP-A-6-93114, J. Membr. Sci., Vol. 199, 167 (2002), J. Membr Sci., Vol.173, 17 (2000), Polymer, Vol.28, 1009 (1987), Solid State Ionics, Vol.106, 219 (1998), Br. Polym. J., Vol.17, 4 ( 1985), Polym. Int., Vol. 50, 812 (2001), aromatic polyether ketones containing sulfonic acid groups, Proceedings of the Society of Polymer Science, Vol. 51, 744-746 (2002) ) Polyimides containing sulfonic acid groups as described in J. Appl. Polym. Sci., Vol. 51, 1399 (1994), J. Appl. Polym. Sci., Vol. 29, 4017 (1984), J. Appl. Polym. Sci., Vol. 29, 4029 (1984), J. Membr. Sci., Vol. 146, 263 (1998), a polyphenylene oxide containing a sulfonic acid group, and a sulfone as described in JP-A-2005-112985. And polyarylene.

These polymer electrolytes may be a copolymer, a random copolymer, a block copolymer, or a graft copolymer. In particular, it is preferable to have a block copolymer structure from the viewpoint of proton conductivity. Among these polymer electrolytes, aromatic polymer electrolytes are preferable from the viewpoint of heat resistance and cost, and further, aromatic polymer electrolytes containing sulfonic acid groups are preferable from the viewpoint of ion conductivity. Further, it may be a polymer electrolyte comprising a composition of a blend of a polymer having no strong acid group or super strong acid group and the polymer having the above strong acid group or super strong acid group within the range of ion exchange capacity described later. Specific examples of such a polymer having no strong acid group or super strong acid group include polymers having no strong acid group or super strong acid group as described above. The combination is preferably a combination of a polymer having a strong acid group or a super strong acid group and a polymer having the same structural unit and no strong acid group or super strong acid group.

  The ion exchange capacity of these polymer electrolytes is preferably in the range of 0.2 meq / g to 4 meq / g, more preferably 0.3 meq / g to 3.5 meq / g. If this range is less than 0.2, for example, in fuel cell applications, proton conductivity is low, while if it is greater than 4, water solubility is undesirable.

The solvent used in the present invention is not particularly limited as long as it dissolves a target polymer electrolyte and a phosphate ester or a salt of a phosphate ester and an amine. For example, in the case of an aromatic polymer electrolyte, , Dimethyl sulfoxide, sulfolane, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N, N-dimethylformamide, N, N-dimethylacetamide, diphenylsulfone, phenol, m-cresol, p -Polar solvents such as chlorophenol can be mentioned.

In the method for producing a polymer electrolyte membrane of the present invention, the drying conditions for evaporating the solvent until the polymer electrolyte solution is cast on a support and heated to a self-supporting membrane are as follows. There is no particular limitation, and it is usually dried in the temperature range of room temperature to the boiling point of the solvent + 20 ° C. for 0.2 minutes to 72 hours. In particular, vacuum drying or hot air drying is preferable because the drying speed can be increased. Further, after peeling the self-supporting film from the support, it can be further dried in the temperature range from room temperature to 280 ° C., if necessary, in the range from 0.2 minutes to 72 hours.

Examples of the material of the support of the present invention include rubbers, resins, metals such as stainless steel, ceramics, and glass. From the viewpoint of durability, metals such as stainless steel, ceramics, and glass are preferable. Examples of the shape include a plate, a belt, and a roll. In particular, the shape of a belt or a roll is preferable because continuous film formation is possible.

In the present invention, the polymer electrolyte solution is cast on a support, heated to evaporate the solvent until it becomes a self-supporting film, the self-supporting film is peeled off from the support, and further dried if necessary. Although the polymer electrolyte membrane obtained by the above method may be used as it is, for example, depending on the use such as a fuel cell, it is preferable to subject the obtained polymer electrolyte membrane to an acid aqueous solution treatment. Furthermore, if necessary, the aqueous acid solution treatment can be performed after the alkaline aqueous solution treatment. Each treatment is performed by immersing the membrane in an aqueous solution for 0.05 to 600 minutes, and may be performed in a batch or continuously. If the processing time is short, the processing becomes insufficient. On the other hand, even if the processing time is long, the effect is not affected. After each process, if necessary, for example
(1) Alkaline treatment ↓
(2) Washing with water ↓
(3) Acid treatment ↓
(4) Washing with water ↓
(5) A water washing step and / or a drying step may be included as in drying.

Alkaline aqueous solution treatment can use NaOH, KOH, sodium carbonate, potassium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate aqueous solution in water, acid aqueous solution treatment can use hydrochloric acid, sulfuric acid, phosphoric acid aqueous solution, The concentration of the aqueous solution is also in the range of 0.01N to 5N. If the concentration of the aqueous solution is lower than 0.01N, the treatment may be insufficient, and if it is higher than 5N, handling of the aqueous solution becomes difficult. Both of the aqueous solution treatments are performed at a temperature in the range of 5 ° C. to 90 ° C. When the temperature is lower than 5 ° C., the treatment becomes insufficient, and when the temperature is higher than 90 ° C., the aqueous solution is difficult to handle. In the washing step, either immersion or shower can be used together. The water washing step is performed at the same time and temperature as the above alkali or acid treatment. Although a drying process is not specifically limited, For example, it is performed by evaporating a water | moisture content by heating in the range of room temperature to 200 degreeC.

When the phosphate ester or the salt of phosphate ester and amine is used in an amount of more than 0.5% by weight, the added phosphate ester or phosphate ester and amine salt is removed by alkaline aqueous solution treatment and subsequent acid aqueous solution treatment. Finally, the phosphate ester or the salt of phosphate ester and amine in the polymer electrolyte membrane is preferably 0.5% by weight or less, more preferably 0.4% by weight or less. If a large amount of phosphate ester or a salt of phosphate ester and amine remains, it is not preferable because durability may be reduced or power generation characteristics may be reduced.

  Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. In addition, the measured value shown in the Example and the comparative example was measured with the following method.

1) Solution viscosity N-methyl-2-pyrrolidone was used as a solvent, measured at a temperature of 25 ° C. using an Ubbelohde viscometer at a concentration of 0.5 g / dL, and calculated using the following formula (1).

（ここで、ｔ_ｓは溶液の測定時間、ｔ_０は溶媒の測定時間、ｃは溶液濃度を示す。）

(Wherein, t _s is the measurement time of the solution, t ₀ is the measurement time of the solvent, c is concentration of solution.)

2) Measurement of proton conductivity Teflon (registered trademark) plate with a 1.9mm width and 10mm length slit in a thermostatic humidity chamber, with platinum wire attached (interval: 2mm) A complex impedance measurement using a 3532 LCR high tester manufactured by Hioki Electric Co., Ltd., with a membrane (width 5 mm x length 20 mm) sandwiched between Teflon (registered trademark) flat plates with a 90-degree longitudinal direction from the platinum wire. To determine the proton conductivity.

3) Evaluation of peelability The solution was cast on a stainless steel plate (SUS304, 40 mm × 150 mm) and dried under predetermined conditions. The self-supporting film was evaluated from the situation when it was peeled from the stainless steel plate.

Example 1

A polymerization flask of block polymer PB is charged with 28.7 g of bis (4-chlorophenyl) sulfone, 18.9 g of 4,4′-biphenol and 16.8 g of potassium carbonate, added with 160 ml of dimethyl sulfoxide and 50 ml of toluene, and heated and stirred under a nitrogen stream. did. While removing generated water together with toluene, the temperature was raised to 175 ° C., and the mixture was stirred at that temperature for 16 hours to prepare a polymer solution A. Separately, a solution in which 73 g of Sumika Excel 7600P (Sumitomo Chemical) was dissolved in 290 ml of dimethyl sulfoxide was prepared. This solution was added to the polymer solution A and stirred at 170 ° C. for 1.5 hours. The solution was poured into a large amount of water to precipitate a white solid and filtered off. The obtained solid was washed twice in hot water and once in methanol to obtain a block polymer PB. The solution viscosity η _{sp / c} of the obtained polymer was 0.71.

20 g of sulfonated block polymer PB of block polymer PB was dissolved in 200 ml of 98% sulfuric acid and stirred at room temperature for 24 hours. The solution was poured into a large amount of water to precipitate a white solid and filtered off. The obtained solid was washed 5 times in water to obtain a polymer SPB. The ion exchange capacity of the obtained polymer was 1.43 mmol / g. The phase separation structure was observed by TEM observation of the film obtained by the method described later, and it was confirmed that the film was a block copolymer.

Film formation and peel test
SPB was dissolved in N, N-dimethylacetamide so as to be 20% by weight, and 0.5% by weight of monostearyl phosphate triethanolamine salt was added to the polymer component to prepare an SPB solution. This solution was cast on a stainless steel plate (SUS304, thickness 2 mm, surface finish 0.8 S) and dried with hot air at 130 ° C. for 1 hour. This film could be easily peeled from the stainless steel plate.

Alkaline aqueous solution treatment and acid treatment The obtained membrane was fixed to a stainless steel frame and heated at 200 ° C. for 30 minutes. The film was removed from the frame, immersed in 1N-NaOH aqueous solution at 25 ° C. for 2 hours, washed with water, and immersed in 1N—H ₂ SO ₄ aqueous solution for 4 hours. After washing twice with water, it was fixed to a stainless steel frame and dried at 50 ° C. The thickness of the obtained film was 35 μm, and the proton conductivity at 50 ° C. and 60% RH was 8.0 × 10 ⁻³ S / cm. On the other hand, the proton conductivity of the membrane just heated at 200 ° C. for 30 minutes was 2.3 × 10 ⁻³ S / cm under the same conditions.

(Comparative Example 1)
A film was formed in the same manner as in Example 1 except that the monostearyl phosphate ester triethanolamine salt was not added. However, it was in close contact with the stainless steel plate and tried to peel off, but the film was torn from the edge.

(Example 2)
Synthesis of random copolymer PR Bis (4-fluorophenyl) sulfone 25.42g, bis (4-hydroxyphenyl) sulfone 15.93g, 4,4'-biphenol 6.77g were added, dimethyl sulfoxide 170ml and toluene 50ml were added and nitrogen stream Under heating and stirring. While removing generated water together with toluene, the temperature was raised to 175 ° C., and the polymer solution was prepared by stirring at that temperature for 16 hours. The solution was poured into a large amount of water to precipitate a white solid and filtered off. The obtained solid was washed twice in hot water and once in methanol to obtain a polymer PR. The solution viscosity η _{sp / c} of the obtained polymer PR was 0.53.

20 g of sulfonated random copolymer PR of random copolymer PR was dissolved in 200 ml of 98% sulfuric acid and stirred at room temperature for 24 hours. The solution was poured into a large amount of water to precipitate a white solid and filtered off. The obtained solid was washed 5 times in water to obtain a polymer SPR. The ion exchange capacity of the obtained polymer was 1.41 mmol / g. By TEM observation of the film obtained by the method described later, the phase separation structure was not observed and was uniform, so that it was confirmed to be a random copolymer.
SPR was dissolved in N, N-dimethylacetamide so as to be 20% by weight, and Separ 365 (Chukyo Oil) was added at 0.3% by weight to the polymer component to prepare an SPR solution. This solution was cast on a stainless steel plate (SUS304, thickness 2 mm, surface finish 0.8) and dried with hot air at 130 ° C. for 1 hour. This film could be easily peeled from the stainless steel plate. The thickness of this film was 38 μm.

(Comparative Example 2)
A film was formed in the same manner as in Example 2 except that Separ 365 (Chukyo Oil) was not added. However, it was in close contact with the stainless steel plate and tried to peel off, but the film was torn from the edge. The thickness of this film was 37 μm.

(Example 3)
10 g of commercially available poly (oxy-1,4-phenyleneoxy-1,4-phenylenecarbonyl-1,4-phenylene) (Aldrich, weight average molecular weight about 20,800, number average molecular weight 10,300, melting point 322 ° C.) The product was dissolved in 100 ml of 98% sulfuric acid and stirred at room temperature for 45 hours. The polymer was precipitated with water and washed with a large amount of water until the wash water was neutral. This was dried under reduced pressure at 60 ° C. to obtain a sulfonated polyetheretherketone. The ion exchange capacity of the obtained polymer was 1.54 mmol / g.
The obtained sulfonated polyetheretherketone was dissolved in N-methyl-2-pyrrolidone so as to be 20% by weight, and 0.5% by weight of Separ 365 (Chukyo Oil) was added to the polymer component to prepare a solution. did. This solution was cast on a stainless steel plate (SUS304, thickness 2 mm, surface finish 0.8) and dried with hot air at 130 ° C. for 1 hour. This film could be easily peeled from the stainless steel plate. The thickness of this film was 30 μm.

(Comparative Example 3)
A film was formed in the same manner as in Example 3 except that Separ 365 (Chukyo Oil) was not added. However, it was in close contact with the stainless steel plate and tried to peel off, but the film was torn from the edge. The thickness of this film was 33 μm.

の構造を有する芳香族ジアミン17.62ｇ、1、3-ビス（4-アミノフェノキシ）ベンゼン4.87ｇ、m-クレゾール155ｇ、トリエチルアミン12ｇを窒素気流（30mL/分）下、80℃で均一溶液になるまで攪拌した。温度を175℃まで昇温し、24時間攪拌し、スルホン化ポリイミド溶液を得た。得られた粘稠溶液（固形分20.8重量％、スルホン酸基がトリエチルアミン塩型で計算した）100ｇに、セパール365（中京油脂）をポリマー成分に対し、0.2重量％添加して、溶液を調整した。この溶液を、ステンレス板（SUS304、厚み2mm、表面仕上げ0.8）上に流延し、130℃で１時間、熱風乾燥した。この膜は、ステンレス板から容易に剥離することが可能であった。この膜の厚みは、27μmであった。
Example 4
1,4,5,8-naphthalenetetracarboxylic dianhydride 13.41g,

17.62 g of aromatic diamine having the following structure, 4.87 g of 1,3-bis (4-aminophenoxy) benzene, 155 g of m-cresol, and 12 g of triethylamine until a homogeneous solution is obtained at 80 ° C. under a nitrogen stream (30 mL / min). Stir. The temperature was raised to 175 ° C. and stirred for 24 hours to obtain a sulfonated polyimide solution. To 100 g of the obtained viscous solution (solid content: 20.8 wt%, sulfonic acid group calculated in triethylamine salt form), 0.2% by weight of Separ 365 (Chukyo Oil) was added to the polymer component to prepare a solution. . This solution was cast on a stainless steel plate (SUS304, thickness 2 mm, surface finish 0.8) and dried with hot air at 130 ° C. for 1 hour. This film could be easily peeled from the stainless steel plate. The thickness of this film was 27 μm.

(Comparative Example 4)
A film was formed in the same manner as in Example 4 except that Separ 365 (Chukyo Oil) was not added. However, it was in close contact with the stainless steel plate, and peeling was attempted, but the film was cut and could not be peeled off. The thickness of this film was 27 μm.

(Synthesis Example 1)
Synthesis of sodium salt of 3,3′-disulfo-4,4′-difluorodiphenylsulfone.
120 g of bis (4-fluorophenyl) sulfone and 250 g of 30% fuming sulfuric acid were charged into a flask and heated at 110 ° C. for 6 hours with stirring. The obtained solution was gradually poured into ice water, and sodium chloride was added to precipitate a solid content. The obtained solid content was dissolved again in water, neutralized with NaOH, and sodium chloride was added to precipitate the solid content. Recrystallized twice from 2-propanol / water (7/3) and dried to give a white solid. In the obtained white solid, a signal with an integrated intensity of 1: 1: 1 was observed at 7.4 to 7.5 ppm, 7.9 to 8.0 ppm, and 8.1 to 8.2 ppm by H-NMR, and 3,3′-disulfo-4, It was confirmed that it was a sodium salt of 4′-difluorodiphenylsulfone.

(Example 5)
Polymerization of polyethersulfone block copolymer PB2 In a four-necked flask equipped with a stirrer, moisture meter, thermometer, and nitrogen introduction tube, 10.17 g of bis (4-fluorophenyl) sulfone, 3,3′-disulfo A sodium salt of -4,4'-difluorodiphenyl sulfone (27.5 g), 4,4-biphenol (18.9 g) and potassium carbonate (17.5 g) were charged, dimethyl sulfoxide (210 ml) and toluene (50 ml) were added, and the mixture was heated and stirred under a nitrogen stream. While removing generated water together with toluene, the temperature was raised to 175 ° C., and the mixture was stirred at that temperature for 16 hours to prepare a hydrophilic prepolymer HP2 solution. Separately, 81.47 g of bis (4-fluorophenyl) sulfone, 78.99 g of bis (4-hydroxyphenyl) sulfone, and 52 g of potassium carbonate were added, 600 ml of dimethyl sulfoxide and 50 ml of toluene were added, and the mixture was heated and stirred under a nitrogen stream. While removing generated water together with toluene, the temperature was raised to 175 ° C., and the mixture was stirred at that temperature for 16 hours to prepare a hydrophobic prepolymer SP2 solution. This SP2 solution was added to the HP2 solution and stirred at 170 ° C. for 1.5 hours. The solution was poured into a large amount of water to precipitate a white solid and filtered off. The obtained solid was washed twice in hot water and once in methanol to obtain a block copolymer PB2. The solution viscosity η _{sp / c} of the obtained polymer was 0.61 dl / g. The ion exchange capacity was 0.59 mmol / g.

[式中、ｐとｑは、各構造単位のモル分率を示し、ｐ＝0．6、ｑ＝0．4である。]
で表されるランダム共重合体の構造であり、疎水性セグメントが、化学式（８）

で表される構造単位を有するスルホン化ブロック共重合体SPB2を得た。得られたポリマーのイオン交換容量は、1.46mmol/gであった。ブレンド物ならばスルホン化後水洗すると、水溶性親水性ポリマーが除去されイオン交換容量が大きく低下する。しかし、SPB2のイオン交換容量は、スルホン化前のPB2のビフェノール残基の各芳香環に1個づつスルホン酸基が導入したとして計算されるイオン交換容量1.49mmol/gとほぼ一致している。このことはSPB2はブレンド物ではなく、親水性セグメントと疎水性セグメントが結合していることを示している。また、後述と同様の方法で得られたSPB2膜のTEM観察で、相分離構造が見られたことから、SBP2は、ブロック共重合体である。疎水性セグメントはこのスルホン化条件ではスルホン化されないため、親水性セグメントのみがスルホン酸基を有する構造である。
Sulfonation of block copolymer PB2 (synthesis of SPB2)
20 g of block copolymer PB2 was dissolved in 200 mL of 98% sulfuric acid and stirred at room temperature for 24 hours. The solution was poured into a large amount of water to precipitate a white solid and filtered off. The obtained solid was washed 5 times in water, and the hydrophilic segment was represented by the chemical formula (7)

[Wherein, p and q represent the mole fraction of each structural unit, and p = 0.6 and q = 0.4. ]
The hydrophobic segment is a structure of a random copolymer represented by the chemical formula (8)

A sulfonated block copolymer SPB2 having a structural unit represented by the formula: The ion exchange capacity of the obtained polymer was 1.46 mmol / g. If the blend is washed with water after sulfonation, the water-soluble hydrophilic polymer is removed and the ion exchange capacity is greatly reduced. However, the ion exchange capacity of SPB2 is almost the same as the ion exchange capacity of 1.49 mmol / g calculated as one sulfonic acid group introduced into each aromatic ring of the biphenol residue of PB2 before sulfonation. This indicates that SPB2 is not a blend but a hydrophilic segment and a hydrophobic segment are bonded. Further, SBP2 is a block copolymer because a phase separation structure was observed by TEM observation of the SPB2 film obtained by the same method as described later. Since the hydrophobic segment is not sulfonated under this sulfonation condition, only the hydrophilic segment has a structure having a sulfonic acid group.

<Film formation>
SPB2 and Separ 365 (Chukyo Yushi) were added in an amount of 0.5% by weight to the polymer component and dissolved in N, N-dimethylacetamide so as to be 20% by weight to prepare a solution. This solution was cast on a stainless steel plate (SUS304, thickness 2 mm, surface finish 0.8) and dried with hot air at 130 ° C. for 1 hour. This film could be easily peeled from the stainless steel plate. The thickness of this film was 24 μm.

(Comparative Example 5)
A film was formed in the same manner as in Example 3 except that Separ 365 (Chukyo Oil) was not added. However, although it was in close contact with the stainless steel plate, peeling was attempted, but the film was torn from the end, and a large deformation was partially stretched. The thickness of this film was 27 μm.

Claims (9)

In the method for producing a polymer electrolyte membrane having a strong acid group or a super strong acid group by a casting method, the chemical formula 1

A phosphoric ester represented by the formula 3

A polyelectrolyte solution containing 0.0005 to 2 parts by weight of a salt with an amine represented by the following formula is cast on a support, the solvent is evaporated by heating to a self-supporting film, and self-support from the support A method for producing a polymer electrolyte membrane, comprising peeling off a functional membrane. The resulting polymer electrolyte membrane, further have rows aqueous acid treatment, method for producing a polymer electrolyte membrane according to claim 1, characterized in that it comprises a step of removing the salt of phosphoric acid ester and an amine. The resulting polymer electrolyte membrane, an alkaline aqueous solution treatment, further have rows acid solution process, the polymer according to claim 1, characterized in that it comprises a step of removing the salt of phosphoric acid ester and an amine Manufacturing method of electrolyte membrane. The method for producing a polymer electrolyte membrane according to any one of claims 1 to 3 , wherein the polymer electrolyte is a hydrocarbon-based polymer electrolyte. The method for producing a polymer electrolyte membrane according to claim 4, wherein the hydrocarbon polymer electrolyte is an aromatic polymer electrolyte having an aromatic ring in the main chain. Aromatic polymer electrolyte, the chemical formula (4)

The method for producing a polymer electrolyte membrane according to claim 5, wherein the polyether is an aromatic polyether having a structural unit represented by: The polymer according to any one of claims 1 to 6, wherein the polymer electrolyte is a composition of a polymer electrolyte having a sulfonic acid group and a polymer having no sulfonic acid group. Manufacturing method of electrolyte membrane. The polymer electrolyte is a block copolymer comprising a hydrophilic segment having a sulfonic acid group and a hydrophobic segment not having a sulfonic acid group, according to any one of claims 1 to 6. The manufacturing method of the polymer electrolyte membrane of description . A polymer electrolyte membrane which is characterized by being manufactured by the manufacturing method of the polymer electrolyte membrane according to any one of claims 1 to 8.