JP2007128763A - Solid polymer electrolyte membrane for fuel cell, and fuel cell - Google Patents

Solid polymer electrolyte membrane for fuel cell, and fuel cell Download PDF

Info

Publication number
JP2007128763A
JP2007128763A JP2005320906A JP2005320906A JP2007128763A JP 2007128763 A JP2007128763 A JP 2007128763A JP 2005320906 A JP2005320906 A JP 2005320906A JP 2005320906 A JP2005320906 A JP 2005320906A JP 2007128763 A JP2007128763 A JP 2007128763A
Authority
JP
Japan
Prior art keywords
electrolyte membrane
fuel cell
solid polymer
polymer electrolyte
radiation
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP2005320906A
Other languages
Japanese (ja)
Other versions
JP5029797B2 (en
Inventor
Noribumi Takahashi
紀文 高橋
Atsuo Kawada
敦雄 川田
Toshio Oba
敏夫 大庭
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shin Etsu Chemical Co Ltd
Original Assignee
Shin Etsu Chemical Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shin Etsu Chemical Co Ltd filed Critical Shin Etsu Chemical Co Ltd
Priority to JP2005320906A priority Critical patent/JP5029797B2/en
Publication of JP2007128763A publication Critical patent/JP2007128763A/en
Application granted granted Critical
Publication of JP5029797B2 publication Critical patent/JP5029797B2/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Landscapes

  • Fuel Cell (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solid polymer electrolyte membrane manufactured by radiation graft polymerization method and has a high proton conductivity and a low methanol permeability concurrently and a fuel cell. <P>SOLUTION: The solid polymer electrolyte membrane for the fuel cell has a styrene based monomer containing at lest one fluorine atom in benzene ring which is graft polymerized in a fluorine based resin having radiation irradiated, and sulfonated. The solid polymer electrolyte membrane manufactured by radiation graft shows a high ion conductivity and has a low methanol permeability, thereby, it is suitable for electrolyte membrane for fuel cell, especially for the electrolyte membrane for direct methanol type fuel cell. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

本発明は、燃料電池用固体高分子電解質膜及び燃料電池に関する。   The present invention relates to a solid polymer electrolyte membrane for a fuel cell and a fuel cell.

固体高分子電解質型イオン交換膜を用いた燃料電池は、作動温度が１００℃以下と低く、そのエネルギー密度が高いことから、電気自動車の電源や簡易補助電源として広く実用化が期待されている。この燃料電池においては固体高分子電解質膜、白金系の触媒、ガス拡散電極、及び高分子電解質膜と電極の接合体などに関する重要な要素技術がある。しかし、この中でも燃料電池としての良好な特性を有する固体高分子電解質膜の開発は最も重要な技術の一つである。   A fuel cell using a solid polymer electrolyte type ion exchange membrane is expected to be widely put into practical use as a power source for electric vehicles or a simple auxiliary power source because of its low operating temperature of 100 ° C. or less and high energy density. In this fuel cell, there are important elemental technologies relating to a solid polymer electrolyte membrane, a platinum-based catalyst, a gas diffusion electrode, and a polymer electrolyte membrane-electrode assembly. However, among these, development of a solid polymer electrolyte membrane having good characteristics as a fuel cell is one of the most important technologies.

固体高分子電解質膜型燃料電池においては、電解質膜の両面にガス拡散電極が複合されており、膜と電極とは実質的に一体構造になっている。このため、電解質膜はプロトンを伝導するための電解質として作用し、また、加圧下においても燃料である水素やメタノールと酸化剤とを直接混合させないための隔膜としての役割も有する。このような電解質膜としては、電解質としてプロトンの移動速度が大きく、イオン交換容量が高いこと、電気抵抗を低く保持するために保水性が一定で、かつ高いことが要求される。一方、隔膜としての役割から、膜の力学的な強度が大きいこと、及び寸法安定性が優れていること、長期の使用に対する化学的な安定性に優れていること、燃料である水素ガスやメタノール、酸化剤である酸素ガスに対して透過性を有しないことなどが要求される。
このような固体高分子電解質膜として、デュポン社によって開発されたフッ素樹脂系のパーフルオロスルホン酸膜「ナフィオン（デュポン社登録商標）」等が一般に用いられてきた。 In a solid polymer electrolyte membrane fuel cell, gas diffusion electrodes are combined on both sides of the electrolyte membrane, and the membrane and the electrode have a substantially integrated structure. For this reason, the electrolyte membrane acts as an electrolyte for conducting protons, and also has a role as a diaphragm for preventing direct mixing of hydrogen or methanol as a fuel with an oxidizing agent even under pressure. Such an electrolyte membrane is required to have a high proton transfer rate as an electrolyte, a high ion exchange capacity, and a constant and high water retention in order to keep electric resistance low. On the other hand, because of its role as a diaphragm, the mechanical strength of the membrane is large, its dimensional stability is excellent, its chemical stability with respect to long-term use is excellent, and hydrogen gas or methanol as fuel In addition, it is required to have no permeability to oxygen gas as an oxidant.
As such a solid polymer electrolyte membrane, a fluororesin-based perfluorosulfonic acid membrane “Nafion (registered trademark of DuPont)” developed by DuPont and the like has been generally used.

しかしながら、「ナフィオン」等の従来のフッ素樹脂系電解質膜は、化学的な耐久性や安定性には優れているが、メタノールを燃料とする直接メタノール型燃料電池（ＤＭＦＣ）では、メタノールが電解質膜を通過するクロスオーバー現象が生じ、出力が低下する問題があった。更に、フッ素樹脂系電解質膜は、モノマーの合成から出発するために、製造工程が多く、コストが高くなる問題があり、実用化する場合の大きな障害になっている。   However, conventional fluororesin electrolyte membranes such as “Nafion” are excellent in chemical durability and stability, but in direct methanol fuel cells (DMFC) using methanol as fuel, methanol is the electrolyte membrane. There was a problem that the crossover phenomenon passing through the slab occurred and the output decreased. Further, since the fluororesin-based electrolyte membrane starts from the synthesis of the monomer, there are problems in that the number of manufacturing steps is increased and the cost is increased, which is a great obstacle when put to practical use.

そのため、前記「ナフィオン」等に替わる固体高分子電解質膜を作製するための技術が検討され、そのような技術の一つとして、フッ素系樹脂に、スチレンなどの炭化水素系モノマーや、炭化水素を一部含むフッ素系モノマーを放射線グラフト重合した電解質膜の作製が検討されている（特許文献１：特開２００１−３４８４３９号公報、特許文献２：特開２００２−３１３３６４号公報、特許文献３：特開２００３−８２１２９号公報等参照）   For this reason, a technique for producing a solid polymer electrolyte membrane replacing “Nafion” or the like has been studied. As one of such techniques, a hydrocarbon monomer such as styrene or a hydrocarbon is added to a fluororesin. Preparation of an electrolyte membrane obtained by radiation graft polymerization of a fluorine-containing monomer containing a part has been studied (Patent Document 1: JP 2001-348439 A, Patent Document 2: JP 2002-313364 A, Patent Document 3: Special (See Kai 2003-82129)

これらの放射線グラフト重合において、スチレンとジビニルベンゼンなどの２種類以上のグラフト原材料と放射線を照射したフッ素樹脂を同時に仕込んで共グラフト重合したスチレン／ジビニルベンゼン共グラフト膜は、「ナフィオン」と同等あるいはそれを凌ぐプロトン伝導度で、メタノール透過度が「ナフィオン」よりも低い電解質膜を得ることが可能であるものの、更なるメタノール透過度の低減が要求されている。しかしながら、このようなスチレン／ジビニルベンゼン共グラフト膜のメタノール透過度を小さくしようとして、架橋剤であるジビニルベンゼン量の増量や、グラフト率の低減を行うと、メタノール透過度は低減するものの、同時にプロトン伝導度が著しく低下してしまうため、高いプロトン伝導度と低いメタノール透過度を併せ持つ固体高分子電解質膜を得ることができないという問題があった。   In these radiation graft polymerizations, styrene / divinylbenzene co-graft membranes prepared by co-grafting two or more graft raw materials such as styrene and divinylbenzene and fluororesin irradiated with radiation at the same time are equivalent to or equivalent to “Nafion”. Although it is possible to obtain an electrolyte membrane having a proton conductivity exceeding that of Nafion and lower than that of Nafion, further reduction in methanol permeability is required. However, increasing the amount of divinylbenzene as a cross-linking agent or reducing the graft ratio in an attempt to reduce the methanol permeability of such a styrene / divinylbenzene co-graft membrane will reduce the methanol permeability, but at the same time, proton Since the conductivity is significantly lowered, there is a problem that a solid polymer electrolyte membrane having both high proton conductivity and low methanol permeability cannot be obtained.

特開２００１−３４８４３９号公報JP 2001-348439 A 特開２００２−３１３３６４号公報JP 2002-313364 A 特開２００３−８２１２９号公報JP 2003-82129 A

従って、本発明は、放射線グラフト重合法により製造され、高いプロトン伝導度と低メタノール透過度を併せ持つ固体高分子電解質膜及び燃料電池を提供することを目的とする。   Accordingly, an object of the present invention is to provide a solid polymer electrolyte membrane and a fuel cell which are produced by a radiation graft polymerization method and have both high proton conductivity and low methanol permeability.

本発明者らは、上記目的を達成するために鋭意検討を行った結果、放射線を照射したフッ素系樹脂に、ベンゼン環に少なくともフッ素原子を１つ含有するスチレン系モノマーをグラフト重合させた後、スルホン化することにより、高いプロトン伝導度と低いメタノール透過度を併せ持つ固体高分子電解質膜が得られることを見出し、本発明をなすに至った。   As a result of intensive studies to achieve the above object, the present inventors have grafted a styrene monomer containing at least one fluorine atom in a benzene ring onto a fluorine resin irradiated with radiation, The inventors have found that a solid polymer electrolyte membrane having both high proton conductivity and low methanol permeability can be obtained by sulfonation, and the present invention has been made.

従って、本発明は、下記燃料電池用固体高分子電解質膜及び燃料電池を提供する。
請求項１：
放射線を照射したフッ素系樹脂に、ベンゼン環に少なくともフッ素原子を１つ含有するスチレン系モノマーをグラフト重合させると共に、スルホン化してなることを特徴とする燃料電池用固体高分子電解質膜。
請求項２：
フッ素系樹脂が、ポリテトラフルオロエチレン、テトラフルオロエチレン−パーフルオロアルキルビニルエーテル系共重合体、テトラフルオロエチレン−ヘキサフルオロプロピレン系共重合体及びエチレン−テトラフルオロエチレン共重合体から選ばれる少なくとも１種である請求項１記載の固体高分子電解質膜。
請求項３：
ベンゼン環に少なくともフッ素原子を１つ含有するスチレン系モノマーが、ｐ−フルオロスチレン、ｏ−フルオロスチレン、ｍ−フルオロスチレンから選ばれる少なくとも１種であることを特徴とする請求項１又は２記載の固体高分子電解質膜。
請求項４：
放射線が電子線であることを特徴とする請求項１乃至３のいずれか１項記載の固体高分子電解質膜。
請求項５：
請求項１乃至４のいずれか１項記載の固体高分子電解質膜が燃料極と空気極との間に設けられていることを特徴とする燃料電池。
請求項６：
メタノールを燃料とするダイレクトメタノール型であることを特徴とする請求項５記載の燃料電池。 Accordingly, the present invention provides the following solid polymer electrolyte membrane for fuel cell and fuel cell.
Claim 1:
A solid polymer electrolyte membrane for a fuel cell, which is obtained by graft polymerization of a styrene monomer containing at least one fluorine atom in a benzene ring to a fluorinated resin irradiated with radiation and sulfonation.
Claim 2:
The fluororesin is at least one selected from polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-hexafluoropropylene copolymer and ethylene-tetrafluoroethylene copolymer. The solid polymer electrolyte membrane according to claim 1.
Claim 3:
The styrene monomer having at least one fluorine atom in the benzene ring is at least one selected from p-fluorostyrene, o-fluorostyrene, and m-fluorostyrene. Solid polymer electrolyte membrane.
Claim 4:
The solid polymer electrolyte membrane according to any one of claims 1 to 3, wherein the radiation is an electron beam.
Claim 5:
5. A fuel cell, wherein the solid polymer electrolyte membrane according to claim 1 is provided between a fuel electrode and an air electrode.
Claim 6:
6. The fuel cell according to claim 5, wherein the fuel cell is a direct methanol type fueled with methanol.

本発明の放射線グラフトにより製造された固体高分子電解質膜は、高いイオン伝導度を示し、かつメタノール透過度が低いため、燃料電池用の電解質膜、特にダイレクトメタノール型燃料電池用の電解質膜として適している。   The solid polymer electrolyte membrane produced by the radiation grafting of the present invention exhibits high ionic conductivity and low methanol permeability, and is therefore suitable as an electrolyte membrane for fuel cells, particularly for direct methanol fuel cells. ing.

本発明の燃料電池用固体高分子電解質膜は、放射線を照射したフッ素系樹脂に、ベンゼン環に少なくともフッ素原子を１つ含有するスチレン系モノマーをグラフト重合させると共に、スルホン化してなるものであるが、この場合、フッ素系樹脂としては、ポリテトラフルオロエチレン、テトラフルオロエチレン−パーフルオロアルキルビニルエーテル系共重合体、テトラフルオロエチレン−ヘキサフルオロプロピレン系共重合体及びエチレン−テトラフルオロエチレン共重合体等の１種又は２種以上が挙げられる。   The solid polymer electrolyte membrane for a fuel cell of the present invention is obtained by graft polymerization of a styrene monomer containing at least one fluorine atom in a benzene ring to a fluorine resin irradiated with radiation and sulfonation. In this case, the fluororesin includes polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, ethylene-tetrafluoroethylene copolymer, etc. 1 type or 2 types or more are mentioned.

一方、ベンゼン環に少なくともフッ素原子を１つ含有するスチレン系モノマーとしては、ｐ−フルオロスチレン、ｏ−フルオロスチレン、ｍ−フルオロスチレン等の１種又は２種以上が好ましく用いられる。   On the other hand, as the styrene monomer containing at least one fluorine atom in the benzene ring, one or more of p-fluorostyrene, o-fluorostyrene, m-fluorostyrene and the like are preferably used.

本発明においては、このようにフッ素系樹脂を使用し、これに放射線を照射した後、上記スチレン系モノマーをグラフト重合させることによって、燃料電池用の固体高分子電解質膜を得るものであるが、かかる放射線グラフト重合法は、公知の方法を採用し得る。   In the present invention, a fluorine-based resin is used in this way, and after irradiation with radiation, the styrene-based monomer is graft polymerized to obtain a solid polymer electrolyte membrane for a fuel cell. A known method can be adopted as the radiation graft polymerization method.

即ち、放射線グラフト重合は、フッ素系樹脂のフィルムに放射線を照射することでラジカルを生成し、そこをグラフト点としてスチレン系モノマーをグラフトする方法であるが、この場合、放射線を用いるグラフト法には、フッ素系樹脂の主鎖に予め放射線を照射して、グラフトの起点となるラジカルを生成させた後、フッ素系樹脂をモノマーと接触させてグラフト反応を行う前照射法と、モノマーとフッ素系樹脂の共存下に放射線を照射する同時照射法とがあるが、本発明においては、いずれの方法をも採用できる。なお、この場合、フッ素系樹脂の膜厚は特に限定されないが、２５〜１００μｍ、特に２５〜８０μｍであることが好ましい。   That is, the radiation graft polymerization is a method in which a radical is generated by irradiating a fluorine resin film with radiation, and a styrene monomer is grafted using the radical as a graft point. A pre-irradiation method in which a main chain of a fluororesin is irradiated with radiation in advance to generate radicals to be grafted, and then the fluororesin is brought into contact with the monomer to carry out a graft reaction; the monomer and the fluororesin In the present invention, any of these methods can be employed. In this case, the film thickness of the fluororesin is not particularly limited, but is preferably 25 to 100 μm, particularly preferably 25 to 80 μm.

本発明でグラフト重合させるために照射する放射線としては、γ線、Ｘ線、電子線、イオンビーム、紫外線等が例示されるが、特に、ラジカル生成の容易さからγ線、電子線が好ましい。   Examples of radiation irradiated for graft polymerization in the present invention include γ-rays, X-rays, electron beams, ion beams, ultraviolet rays, and the like, and γ-rays and electron beams are particularly preferable because of the ease of radical generation.

放射線の吸収線量は、１ｋＧｙ以上になるように照射されることが好ましく、望ましい吸収線量は１〜１００ｋＧｙ、更に望ましい吸収線量は１〜５０ｋＧｙである。１ｋＧｙ未満であると、ラジカル生成量が少なく、所望のイオン伝導度を得るのに十分なグラフト率が得られない場合がある。１００ｋＧｙを超えるとフッ素系樹脂の伸び、強度などの機械特性が低下する場合がある。   The absorbed dose of radiation is preferably 1 kGy or more, preferably 1 to 100 kGy, and more preferably 1 to 50 kGy. If it is less than 1 kGy, the amount of radical generation is small, and a graft rate sufficient to obtain the desired ionic conductivity may not be obtained. If it exceeds 100 kGy, mechanical properties such as elongation and strength of the fluororesin may be deteriorated.

更に、放射線の照射は、ヘリウム、窒素、アルゴンガス等の不活性ガス雰囲気中で行うのが好ましく、該ガス中の酸素濃度は１００ｐｐｍ以下、特に５０ｐｐｍ以下が好ましいが、必ずしも酸素不在下で行う必要はない。   Further, the irradiation with radiation is preferably performed in an inert gas atmosphere such as helium, nitrogen, or argon gas, and the oxygen concentration in the gas is preferably 100 ppm or less, and particularly preferably 50 ppm or less. There is no.

ここで、放射線を照射したフッ素系樹脂にグラフトするスチレン系モノマーの使用量は、フッ素系樹脂１００質量部に対してスチレン系モノマーを１，０００〜１００，０００質量部、特に４，０００〜２０，０００質量部使用することが好ましい。ラジカル反応性モノマーが少なすぎると接触が不十分になる場合があり、多すぎるとラジカル反応性モノマーが効率的に使用できなくなるおそれがある。   Here, the used amount of the styrene monomer grafted to the fluororesin irradiated with radiation is 1,000 to 100,000 parts by mass, particularly 4,000 to 20 parts by mass of the styrene monomer with respect to 100 parts by mass of the fluororesin. It is preferable to use 1,000 parts by mass. If the amount of the radical reactive monomer is too small, the contact may be insufficient. If the amount is too large, the radical reactive monomer may not be used efficiently.

これらスチレン系モノマーをグラフト重合するに際しては、アゾビスイソブチルニトリルなどの重合開始剤を本発明の目的を損なわない範囲で適宜用いてもよい。   In graft polymerization of these styrenic monomers, a polymerization initiator such as azobisisobutyl nitrile may be appropriately used as long as the object of the present invention is not impaired.

更に、グラフト反応時に溶媒を用いることができ、溶媒としては、反応性モノマーを均一に溶解するものが好ましく、例えばアセトン、メチルエチルケトン等のケトン類、酢酸エチル、酢酸ブチル等のエステル類、メチルアルコール、エチルアルコール、プロピルアルコール、ブチルアルコール等のアルコール類、テトラヒドロフラン、ジオキサン等のエーテル類、Ｎ，Ｎ−ジメチルホルムアミド、Ｎ，Ｎ−ジメチルアセトアミド、ベンゼン、トルエン、キシレン等の芳香族炭化水素、ｎ−ヘプタン、ｎ−ヘキサン、シクロヘキサン等の脂肪族又は脂環族炭化水素、あるいはこれらの混合溶媒を用いることができる。   Further, a solvent can be used during the grafting reaction, and the solvent is preferably one that uniformly dissolves the reactive monomer, for example, ketones such as acetone and methyl ethyl ketone, esters such as ethyl acetate and butyl acetate, methyl alcohol, Alcohols such as ethyl alcohol, propyl alcohol and butyl alcohol, ethers such as tetrahydrofuran and dioxane, aromatic hydrocarbons such as N, N-dimethylformamide, N, N-dimethylacetamide, benzene, toluene and xylene, n-heptane In addition, aliphatic or alicyclic hydrocarbons such as n-hexane and cyclohexane, or a mixed solvent thereof can be used.

上記グラフト重合の反応条件としては、窒素、アルゴンなどの不活性ガス雰囲気中で０〜１００℃、特に４０〜８０℃の温度で１〜４０時間、特に４〜２０時間の反応時間とすることが好ましい。   As the reaction conditions for the graft polymerization, a reaction time of 0 to 100 ° C., particularly 40 to 80 ° C., and 1 to 40 hours, particularly 4 to 20 hours, in an inert gas atmosphere such as nitrogen or argon. preferable.

上述したように、放射線を照射したフッ素系樹脂に上記フッ素原子含有スチレン系モノマーをグラフト重合させ、更にスルホン化させることにより、固体高分子電解質膜を得ることができる。   As described above, a solid polymer electrolyte membrane can be obtained by graft polymerization of the fluorine atom-containing styrene monomer to a fluorine resin irradiated with radiation and further sulfonation.

グラフトした膜は、クロロスルホン酸−ジクロロエタン中に浸漬することによってクロロスルホン酸基を導入することができる。クロロスルホン酸と反応させた膜は、水酸化カリウムや水酸化ナトリウム水溶液中で反応させ、スルホン酸アルカリ塩とし、引き続き塩酸などで酸処理することによってスルホン化することができる。   The grafted membrane can introduce chlorosulfonic acid groups by immersing in chlorosulfonic acid-dichloroethane. The membrane reacted with chlorosulfonic acid can be sulfonated by reacting in an aqueous solution of potassium hydroxide or sodium hydroxide to form an alkali salt of sulfonic acid, followed by acid treatment with hydrochloric acid or the like.

本発明の固体高分子電解質膜は、燃料電池の燃料極と空気極の間に設けられる固体高分子電解質膜として使用できるものであり、固体高分子電解質膜の両面に触媒層・燃料拡散層及びセパレータを配置することで、特にダイレクトメタノール型燃料電池用電解質膜として好適に使用されて、メタノールのクロスオーバーがなく、電池特性に優れた燃料電池を得ることが可能である。なお、燃料極、空気極の構成、材質、燃料電池の構成は公知のものとすることができる。   The solid polymer electrolyte membrane of the present invention can be used as a solid polymer electrolyte membrane provided between a fuel electrode and an air electrode of a fuel cell. A catalyst layer, a fuel diffusion layer and By disposing the separator, it is possible to obtain a fuel cell that is suitably used particularly as an electrolyte membrane for a direct methanol fuel cell, has no methanol crossover, and has excellent cell characteristics. Note that the configurations and materials of the fuel electrode and the air electrode and the configuration of the fuel cell can be known.

以下、実施例及び比較例を示し、本発明を具体的に説明するが、本発明は下記の実施例に制限されるものではない。   EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example.

［実施例１］
厚さ２５μｍのエチレン−テトラフルオロエチレン共重合体（Ｎｏｒｔｏｎ社製）に室温で電子線を２０ｋＧｙ照射した後に、ｐ−フルオロスチレン１２質量部、トルエン１２質量部、アゾビスイソブチルニトリル０．０１質量部が仕込んであるアンプルに浸漬し、十分窒素置換を行った後、５０℃で１６時間加熱し、グラフト率が３１％のｐ−フルオロスチレングラフト重合膜を得た。
グラフト率＝
［（グラフト後フィルム質量−グラフト前フィルム質量）／グラフト前フィルム質量］
×１００（％）
なお、グラフト後フィルム質量はグラフト後のフィルムをトルエンで１回、アセトンで３回洗浄し、６０℃で２時間真空乾燥後の質量とした。 [Example 1]
An ethylene-tetrafluoroethylene copolymer (manufactured by Norton) having a thickness of 25 μm was irradiated with an electron beam at 20 kGy at room temperature, and then 12 parts by mass of p-fluorostyrene, 12 parts by mass of toluene, 0.01 parts by mass of azobisisobutylnitrile Was immersed in an ampule charged with No. 2 and sufficiently substituted with nitrogen, and then heated at 50 ° C. for 16 hours to obtain a p-fluorostyrene graft polymerized film having a graft ratio of 31%.
Graft rate =
[(Film weight after grafting−film weight before grafting) / film weight before grafting]
× 100 (%)
The post-graft film mass was the mass after vacuum-drying at 60 ° C. for 2 hours after washing the grafted film once with toluene and three times with acetone.

上記グラフト重合膜を、クロロスルホン酸３０質量部と１，２−ジクロロエタン７０質量部の混合液に浸漬し、５０℃で２時間加熱後、９０℃の１Ｎ苛性カリ水溶液中に２時間浸漬することで加水分解し、続いて９０℃の２Ｎ塩酸に２時間浸漬後、純水で３回洗浄し、スルホン酸基を含有する固体高分子電解質膜を得た。
得られた固体高分子電解質膜の純水中に１時間浸漬後の表面に平行な方向のイオン伝導度は０．０８Ｓ／ｃｍであり、１０Ｍでのメタノール透過度は、０．５４ｋｇ／ｍ2・ｈであった。 The graft polymerized membrane is immersed in a mixed solution of 30 parts by mass of chlorosulfonic acid and 70 parts by mass of 1,2-dichloroethane, heated at 50 ° C. for 2 hours, and then immersed in a 1N caustic potash aqueous solution at 90 ° C. for 2 hours. It was hydrolyzed and subsequently immersed in 2N hydrochloric acid at 90 ° C. for 2 hours and then washed 3 times with pure water to obtain a solid polymer electrolyte membrane containing sulfonic acid groups.
The ionic conductivity in the direction parallel to the surface of the obtained solid polymer electrolyte membrane after being immersed in pure water for 1 hour is 0.08 S / cm, and the methanol permeability at 10 M is 0.54 kg / m 2.・ It was h.

［比較例１］
厚さ２５μｍのエチレン−テトラフルオロエチレン共重合体（Ｎｏｒｔｏｎ社製）に室温で電子線を２ｋＧｙ照射した後に、スチレン１２質量部、トルエン１２質量部、アゾビスイソブチルニトリル０．００３質量部が仕込んであるアンプルに浸漬し、十分窒素置換を行った後、６０℃で１６時間加熱し、グラフト率が３３％のスチレングラフト重合膜を得た。
グラフト率＝
［（グラフト後フィルム質量−グラフト前フィルム質量）／グラフト前フィルム質量］
×１００（％）
なお、グラフト後フィルム質量はグラフト後のフィルムをトルエンで１回、アセトンで３回洗浄し、６０℃で２時間真空乾燥後の質量とした。 [Comparative Example 1]
An ethylene-tetrafluoroethylene copolymer (manufactured by Norton) having a thickness of 25 μm was irradiated with an electron beam at 2 kGy at room temperature, and then charged with 12 parts by mass of styrene, 12 parts by mass of toluene, and 0.003 parts by mass of azobisisobutylnitrile. After being immersed in an ampoule and sufficiently purged with nitrogen, it was heated at 60 ° C. for 16 hours to obtain a styrene graft polymerized film having a graft ratio of 33%.
Graft rate =
[(Film weight after grafting−film weight before grafting) / film weight before grafting]
× 100 (%)
The post-graft film mass was the mass after vacuum-drying at 60 ° C. for 2 hours after washing the grafted film once with toluene and three times with acetone.

上記グラフト重合膜を、クロロスルホン酸３０質量部と１，２−ジクロロエタン７０質量部の混合液に浸漬し、５０℃で２時間加熱後、９０℃の１Ｎ苛性カリ水溶液中に２時間浸漬することで加水分解し、続いて９０℃の２Ｎ塩酸に２時間浸漬後、純水で３回洗浄し、スルホン酸基を含有する固体高分子電解質膜を得た。
得られた固体高分子電解質膜の純水中に１時間浸漬後の表面に平行な方向のイオン伝導度は０．０９Ｓ／ｃｍであり、１０Ｍでのメタノール透過度は、１．１ｋｇ／ｍ2・ｈであった。
The graft polymerized membrane is immersed in a mixed solution of 30 parts by mass of chlorosulfonic acid and 70 parts by mass of 1,2-dichloroethane, heated at 50 ° C. for 2 hours, and then immersed in a 1N caustic potash aqueous solution at 90 ° C. for 2 hours. It was hydrolyzed and subsequently immersed in 2N hydrochloric acid at 90 ° C. for 2 hours and then washed 3 times with pure water to obtain a solid polymer electrolyte membrane containing sulfonic acid groups.
The ionic conductivity in the direction parallel to the surface of the obtained solid polymer electrolyte membrane after being immersed in pure water for 1 hour is 0.09 S / cm, and the methanol permeability at 10 M is 1.1 kg / m 2.・ It was h.

Claims (6)

放射線を照射したフッ素系樹脂に、ベンゼン環に少なくともフッ素原子を１つ含有するスチレン系モノマーをグラフト重合させると共に、スルホン化してなることを特徴とする燃料電池用固体高分子電解質膜。   A solid polymer electrolyte membrane for a fuel cell, which is obtained by graft polymerization of a styrene monomer containing at least one fluorine atom in a benzene ring to a fluorinated resin irradiated with radiation and sulfonation. フッ素系樹脂が、ポリテトラフルオロエチレン、テトラフルオロエチレン−パーフルオロアルキルビニルエーテル系共重合体、テトラフルオロエチレン−ヘキサフルオロプロピレン系共重合体及びエチレン−テトラフルオロエチレン共重合体から選ばれる少なくとも１種である請求項１記載の固体高分子電解質膜。   The fluororesin is at least one selected from polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-hexafluoropropylene copolymer and ethylene-tetrafluoroethylene copolymer. The solid polymer electrolyte membrane according to claim 1. ベンゼン環に少なくともフッ素原子を１つ含有するスチレン系モノマーが、ｐ−フルオロスチレン、ｏ−フルオロスチレン、ｍ−フルオロスチレンから選ばれる少なくとも１種であることを特徴とする請求項１又は２記載の固体高分子電解質膜。   The styrene monomer having at least one fluorine atom in the benzene ring is at least one selected from p-fluorostyrene, o-fluorostyrene, and m-fluorostyrene. Solid polymer electrolyte membrane. 放射線が電子線であることを特徴とする請求項１乃至３のいずれか１項記載の固体高分子電解質膜。   The solid polymer electrolyte membrane according to any one of claims 1 to 3, wherein the radiation is an electron beam. 請求項１乃至４のいずれか１項記載の固体高分子電解質膜が燃料極と空気極との間に設けられていることを特徴とする燃料電池。   A fuel cell, wherein the solid polymer electrolyte membrane according to any one of claims 1 to 4 is provided between a fuel electrode and an air electrode. メタノールを燃料とするダイレクトメタノール型であることを特徴とする請求項５記載の燃料電池。
6. The fuel cell according to claim 5, wherein the fuel cell is a direct methanol type fueled with methanol.
JP2005320906A 2005-11-04 2005-11-04 Solid polymer electrolyte membrane for fuel cell and fuel cell Expired - Fee Related JP5029797B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2005320906A JP5029797B2 (en) 2005-11-04 2005-11-04 Solid polymer electrolyte membrane for fuel cell and fuel cell

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2005320906A JP5029797B2 (en) 2005-11-04 2005-11-04 Solid polymer electrolyte membrane for fuel cell and fuel cell

Publications (2)

Publication Number Publication Date
JP2007128763A true JP2007128763A (en) 2007-05-24
JP5029797B2 JP5029797B2 (en) 2012-09-19

Family

ID=38151243

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2005320906A Expired - Fee Related JP5029797B2 (en) 2005-11-04 2005-11-04 Solid polymer electrolyte membrane for fuel cell and fuel cell

Country Status (1)

Country Link
JP (1) JP5029797B2 (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004087380A (en) * 2002-08-28 2004-03-18 Hitachi Cable Ltd Electrolyte film for fuel cell, and its manufacturing method
JP2006066174A (en) * 2004-08-26 2006-03-09 Nitto Denko Corp Electrolyte film for fuel cell with excellent acid resistance
JP2006179301A (en) * 2004-12-22 2006-07-06 Japan Atomic Energy Agency High-durability polymer electrolyte membrane for fuel cell with cross-linked structure introduced therein
JP2006344552A (en) * 2005-06-10 2006-12-21 Japan Atomic Energy Agency Cross-link type electrolyte membrane and its manufacturing method

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004087380A (en) * 2002-08-28 2004-03-18 Hitachi Cable Ltd Electrolyte film for fuel cell, and its manufacturing method
JP2006066174A (en) * 2004-08-26 2006-03-09 Nitto Denko Corp Electrolyte film for fuel cell with excellent acid resistance
JP2006179301A (en) * 2004-12-22 2006-07-06 Japan Atomic Energy Agency High-durability polymer electrolyte membrane for fuel cell with cross-linked structure introduced therein
JP2006344552A (en) * 2005-06-10 2006-12-21 Japan Atomic Energy Agency Cross-link type electrolyte membrane and its manufacturing method

Also Published As

Publication number Publication date
JP5029797B2 (en) 2012-09-19

Similar Documents

Publication Publication Date Title
US8232353B2 (en) Processes for producing nano-space controlled polymer ion-exchange membranes
JP4748410B2 (en) Method for producing a polymer electrolyte membrane for a highly durable fuel cell incorporating a crosslinked structure
US9382367B2 (en) Polymer electrolyte membrane composed of aromatic polymer membrane base and method for producing the same
JP4514643B2 (en) Solid polymer electrolyte membrane for direct methanol fuel cell, method for producing the same, and direct methanol fuel cell
JP2003261697A (en) Fluoropolymer ion exchanger membrane having excellent oxidation resistance and widely ranging ion exchange capacity and manufacturing method thereof
JP2004059752A (en) Electrolyte membrane for fuel cell comprising crosslinked fluororesin base
JP2007258048A (en) Forming method of polymer electrolyte membrane for fuel cell, the electrolyte membrane, and membrane electrode conjugant for fuel cell using the membrane
JP4576620B2 (en) Method for producing nanostructure control polymer ion exchange membrane
JP5158353B2 (en) Fuel cell electrolyte membrane and method for producing fuel cell electrolyte membrane / electrode assembly
JP4822389B2 (en) Electrolyte membrane with excellent oxidation resistance
JP2009151938A (en) Solid polymer electrolyte membrane for fuel cell and fuel cell
JP2008195748A (en) Crosslinked aromatic polymer electrolyte membrane and its manufacturing method
JP4692714B2 (en) Method for producing solid polymer electrolyte membrane for fuel cell
JP4434666B2 (en) Method for producing solid polymer electrolyte membrane and fuel cell
JP5029797B2 (en) Solid polymer electrolyte membrane for fuel cell and fuel cell
JP4390047B2 (en) Solid polymer electrolyte membrane, method for producing the same, and fuel cell
JP2006351244A (en) Solid polyelectrolyte membrane, manufacturing method therefor, and fuel cell
JP2007194019A (en) Cross-linked electrolyte film and its manufacturing method
JP4645794B2 (en) Solid polymer electrolyte membrane and fuel cell
JP2006307051A (en) Solid polymer electrolytic membrane and method for producing the same, and fuel battery
JP5158309B2 (en) ELECTROLYTE MEMBRANE FOR SOLID POLYMER FUEL CELL AND METHOD FOR PRODUCING THE SAME
JP2005142014A (en) Electrolyte membrane for fuel cells superior in acid resistance
JP2009206019A (en) Method of manufacturing polymer electrolyte membrane for fuel cell, electrolyte membrane manufactured thereby and membrane electrode assembly for fuel cell using the membrane
JP4683181B2 (en) Method for producing solid polymer electrolyte membrane for fuel cell
JP5316413B2 (en) Solid polymer electrolyte membrane, method for producing solid polymer electrolyte membrane, and fuel cell

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20071025

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20101115

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20110427

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20110620

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20120314

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20120514

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20120530

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20120612

R150 Certificate of patent or registration of utility model

Free format text: JAPANESE INTERMEDIATE CODE: R150

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20150706

Year of fee payment: 3

LAPS Cancellation because of no payment of annual fees