JP2004111146A - Polymer composition for fuel cell sealing compound, fuel cell sealing component and manufacturing method of the same, as well as fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polymer composition with excellent high speed molding property which can be prepared for a fuel cell sealing component with excellent heat-resistant property, acid-resistant property, and gas permeation-resistant property (gas barrier property); the fuel cell sealing component obtained by interlinking the polymer composition; a manufacturing method of the fuel cell sealing component; and a fuel cell having the fuel cell sealing component. <P>SOLUTION: The polymer composition for the fuel cell sealing component contains organic polymer containing a vinyl group (excepting ethylene-α olefin non-conjugated polyene copolymer)[A], and a compound containing -SiH group [B]. It is recommendable that the ingredient [B] contains at least two SiH groups in one molecule. The fuel cell sealing component is obtained from the polymer composition. By using such polymer composition, the fuel cell sealing component with quick interlinking speed, excellent productivity, compression permanent set-resistant property, gas barrier property, heat-resistant property, acid-resistant property, and cooling water-resistant property or the like is obtained. <P>COPYRIGHT: (C)2004,JPO

Description

【００３５】
【化２】

また、前述した一般組成式　　Ｒ^４ _ｂＨ_ｃＳｉＯ_{（４−ｂ−ｃ）／２}
で表わされる化合物において、置換基Ｒ^４の少なくとも１個以上は炭素数３以上の炭化水素基、例えばプロピル基、ブチル基、フェニル基であることが好ましい。この範囲にあると特に電極の耐汚染性に優れる。
たとえばＣ_６Ｈ_５−Ｓｉ（ＯＳｉ（ＣＨ_３）_２Ｈ）_３などを例示することができる。
【００３６】
ＳｉＨ基含有化合物［Ｂ］は、ビニル基を含有する有機重合体（ただしエチレン・α−オレフィン・非共役ジエン共重合体を除く）［Ａ］１００重量部に対して、０．１〜１００重量部、好ましくは０．１〜７５重量部、より好ましくは０．１〜５０重量部、さらに好ましくは０．２〜３０重量部、さらにより好ましくは０．２〜２０重量部、特に好ましくは０．５〜１０重量部、より好ましくは２〜８重量部、最も好ましくは４〜８重量部の割合で用いられる。上記範囲内の割合でＳｉＨ基含有化合物［Ｂ］を用いると、耐圧縮永久歪み性に優れるとともに、架橋密度が適度で強度特性および伸び特性に優れた架橋ゴム成形体を形成できる重合体組成物が得られる。１００重量部を超える割合でＳｉＨ基含有化合物［Ｂ］を用いると、コスト的に不利になるので好ましくない。
【００３７】
また、ＳｉＨ基含有化合物［Ｂ］が、ビニル基を含有する有機重合体（ただしエチレン・α−オレフィン・非共役ジエン共重合体を除く）［Ａ］（［Ａ］成分）に含まれる脂肪族不飽和結合（アルケニル基及びジエン基など）１個に対し、ケイ素原子に結合した水素原子（≡ＳｉＨ基）の割合が０．２〜１０の範囲が適当であり、好ましくは０．７〜５となるような範囲が適当である。０．２以下であると、ビニル基が多量に残存し、耐熱老化性が悪化する場合がある。一方、１０以上であると、未反応のＳｉＨ基含有化合物が多量に残存し電極汚染性が悪化する場合がある。
【００３８】
［触媒［Ｃ］］
本発明で任意成分として用いられる触媒［Ｃ］は、付加反応触媒であり、ＥＰＤＭ以外のビニル基を含有する有機重合体［Ａ］成分のアルケニル基などと、ＳｉＨ基含有化合物［Ｂ］のＳｉＨ基との付加反応（アルケンのヒドロシリル化反応など）を促進するものである。
【００３９】
該触媒［Ｃ］としては、通常、たとえば白金系触媒、パラジウム系触媒、ロジウム系触媒等の白金族元素よりなる付加反応用触媒が用いられるが、本発明においては、白金系触媒が好ましい。白金系触媒を含めて、触媒［Ｃ］としては、周期律表８族元素金属、特に好ましくは白金と、ビニル基および／またはカルボニル基を含む化合物との錯体を用いることが望ましい。
【００４０】
カルボニル基を含む化合物としては、カルボニル、オクタナル等が好ましい。これらと白金との錯体としては、具体的には、白金−カルボニル錯体、白金−オクタナル錯体、白金−カルボニルブチル環状シロキサン錯体、白金−カルボニルフェニル環状シロキサン錯体などが挙げられる。
ビニル基を含む化合物としては、ビニル基含有オルガノシロキサンが好ましい。これらと白金との錯体としては、具体的には、白金−ジビニルテトラメチルジシロキサン錯体、白金−ジビニルテトラエチルジシロキサン錯体、白金−ジビニルテトラプロピルジシロキサン錯体、白金−ジビニルテトラブチルジシロキサン錯体、白金−ジビニルテトラフェニルジシロキサン錯体が挙げられる。
【００４１】
ビニル基含有オルガノシロキサンの中でも、ビニル基含有環状オルガノシロキサンが好ましい。これらと白金との錯体としては、白金−ビニルメチル環状シロキサン錯体、白金−ビニルエチル環状シロキサン錯体、白金−ビニルプロピル環状シロキサン錯体が挙げられる。
ビニル基含有オルガノシロキサンは、それ自体を金属に対する配位子としてもよいが、他の配位子を配位させる際の溶媒として用いてもよい。ビニル基含有オルガノシロキサンを溶媒として用い、前述のカルボニル基を含む化合物を配位子とする錯体は、本発明の触媒［Ｃ］として、特に好ましい。
【００４２】
このような錯体としては、具体的には、白金−カルボニル錯体のビニルメチル環状シロキサン溶液、白金−カルボニル錯体のビニルエチル環状シロキサン溶液、白金−カルボニル錯体のビニルプロピル環状シロキサン溶液、白金−カルボニル錯体のジビニルテトラメチルジシロキサン溶液、白金−カルボニル錯体のジビニルテトラエチルジシロキサン溶液、白金−カルボニル錯体のジビニルテトラプロピルジシロキサン溶液、白金−カルボニル錯体のジビニルテトラブチルジシロキサン溶液、白金−カルボニル錯体のジビニルテトラフェニルジシロキサン溶液が挙げられる。
【００４３】
これらの錯体からなる触媒は、ビニル基および／またはカルボニル基を含む化合物以外の成分を更に含んでいてもよい。たとえばビニル基および／またはカルボニル基を含む化合物以外の溶媒を含んでいてもよい。これらの溶媒としては、各種アルコールや、キシレン等を挙げることができるが、これらに制限されるものではない。
【００４４】
アルコールとしては、具体的には、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、イソプロピルアルコール、ブチルアルコール、ｓｅｃ−ブチルアルコール、ｔｅｒｔ−　ブチルアルコール、ｎ−アミルアルコール、イソアミルアルコール、ヘキシルアルコール、ヘプチルアルコール、オクチルアルコール、カプリルアルコール、ノニルアルコール、デシルアルコール、ウンデシルアルコール、ラウリルアルコール、トリデシルアルコール、ミリスチルアルコール、セチルアルコール、ステアリルアルコール、エイコシルアルコール等の脂肪族飽和アルコール類；
アリルアルコール、クロチルアルコール等の脂肪族不飽和アルコール類；
シクロペンタノール、シクロヘキサノール等の脂環式アルコール類；
ベンジルアルコール、シンナミルアルコール等の芳香族アルコール類；
フルフリルアルコール等の複素環式アルコール類などが挙げられる。
【００４５】
アルコールを溶媒として用いた例として、白金−オクタナル／オクタノール錯体が挙げられる。これらの溶媒を含むことにより、触媒の取扱いや、重合体組成物への混合が容易になる等の利点が生ずる。
【００４６】
以上に挙げた各種触媒のうちで、白金−カルボニル錯体のビニルメチル環状シロキサン溶液（中でも下記化学式１で示される錯体が好ましい）、白金−ビニルメチル環状シロキサン錯体（中でも化学式２で示される錯体が好ましい）、白金−ジビニルテトラメチルジシロキサン錯体（中でも化学式３で示される錯体が好ましい）、白金−オクタナル／オクタノール錯体等が実用上好ましく、その中でも、白金−カルボニルビニルメチル環状シロキサン錯体が特に好ましい。
【００４７】
ここで上記の錯体を形成する化合物として、ビニル基含有オルガノシロキサン、カルボニル基含有オルガノシロキサンなどオルガノシロキサンを用いる場合は、その量は特に制限はないが、触媒１ｍｏｌに対して０．１〜１００ｍｏｌであることが好ましい。上限は、触媒１ｍｏｌに対して２０モル％以下であることがより好ましく、６モル％以下であることがさらに好ましい。具体的には触媒１ｍｏｌに対して０．１〜２０ｍｏｌ、さらには０．１〜６ｍｏｌの割合が好ましい態様である。この範囲にあると特に電極の耐汚染性にも優れる。
【００４８】
またその他アルデヒド、ケトンなどのカルボニル化合物を用いる場合は、その量は触媒１ｍｏｌに対して、０．１〜１０００ｍｏｌの範囲にあることが好ましく、０．１〜１００ｍｏｌの範囲にあることがさらに好ましい。
【００４９】
またこのような錯体を形成する化合物としては、沸点が１００℃以上、好ましくは１２０℃以上、より好ましくは１５０℃以上、さらに好ましくは１７０℃以上であるようなものも好ましい態様である。この範囲にあると特に電極の耐汚染性に優れる。
【００５０】
化学式１：　Ｐｔ^０・ＣＯ・（ＣＨ_２＝ＣＨ（Ｍｅ）ＳｉＯ）_４
化学式２：　Ｐｔ^０・（ＣＨ_２＝ＣＨ（Ｍｅ）ＳｉＯ）_４
化学式３：　Ｐｔ^０−１．５［（ＣＨ_２＝ＣＨ（Ｍｅ）_２Ｓｉ）_２Ｏ］
これらの触媒に含まれる周期律表８族元素金属（好ましくは白金）の割合は、通常０．１〜１０重量％、好ましくは１〜５重量％、さらに好ましくは２〜４重量％、特に好ましくは２．５〜３．５重量％である。
【００５１】
触媒［Ｃ］は、ビニル基を含有する有機重合体［Ａ］（ただしエチレン・α−オレフィン・非共役ジエン共重合体を除く）に対して、通常０．１〜１００，０００重量ｐｐｍ、好ましくは０．１〜１０，０００重量ｐｐｍ、さらに好ましくは１〜５，０００重量ｐｐｍ、特に好ましくは５〜１，０００重量ｐｐｍの割合で用いられる。
【００５２】
上記範囲内の割合で触媒［Ｃ］を用いると、架橋密度が適度で、強度特性および伸び特性に優れる架橋ゴム成形体を形成できる重合体組成物が得られる。１００，０００重量ｐｐｍを超える割合で触媒［Ｃ］を用いると、コスト的に不利になる。
なお、本発明においては、上記触媒［Ｃ］を含まない重合体組成物の未架橋ゴム成形体に、光、γ線、電子線等を照射して架橋ゴム成形体を得ることもできる。
【００５３】
［反応抑制剤［Ｄ］］
本発明で触媒［Ｃ］とともに任意成分として用いられる反応抑制剤［Ｄ］としては、ベンゾトリアゾール、エチニル基含有アルコール（たとえばエチニルシクロヘキサノール等）、アクリロニトリル、アミド化合物（たとえばＮ，Ｎ−ジアリルアセトアミド、Ｎ，Ｎ−ジアリルベンズアミド、Ｎ，Ｎ，Ｎ’，Ｎ’−テトラアリル−ｏ−フタル酸ジアミド、Ｎ，Ｎ，Ｎ’，Ｎ’−テトラアリル−ｍ−フタル酸ジアミド、Ｎ，Ｎ，Ｎ’，Ｎ’−テトラアリル−ｐ−フタル酸ジアミドなど）、イオウ、リン、窒素、アミン化合物、イオウ化合物、リン化合物、スズ、スズ化合物、ハイドロパーオキサイド等の有機過酸化物などが好ましく挙げられる。
【００５４】
この中でも、シロキサン結合を有しない反応抑制剤が好ましい。ここでシロキサン結合とは、（Ｓｉ−Ｏ−）結合のことをいう。
【００５５】
さらにこの中でも、炭素原子、水素原子、酸素原子からなる構造を有する反応抑制剤が好ましい。炭素原子、水素原子、酸素原子のみからなることが特に好ましい一つの態様である。この範囲にあると特に電極の耐汚染性に優れる。
【００５６】
また、反応抑制剤としては、上記のような特性を有すると共に、または上記のような特性とは関係なく、沸点が１００℃以上、好ましくは１２０℃以上、より好ましくは１５０℃以上、特に好ましくは１７０℃以上である化合物を好ましく挙げることができる。上限は特にはない。このような化合物は、特に電極の耐汚染性に優れる。
【００５７】
反応抑制剤［Ｄ］は、ビニル基を含有する有機重合体［Ａ］１００重量部に対して、０〜５０重量部、通常０．０００１〜５０重量部、好ましくは０．０００１〜３０重量部、より好ましくは０．０００１〜２０重量部、さらに好ましくは０．０００１〜１０重量部、特に好ましくは０．０００１〜５重量部の割合で用いられる。
【００５８】
５０重量部以下の割合で反応抑制剤［Ｄ］を用いると、架橋スピードが速く、架橋ゴム成形体の生産性に優れた重合体組成物が得られる。５０重量部を超える割合で反応抑制剤［Ｄ］を用いると、コスト的に不利になるので好ましくない。
【００５９】
本発明の重合体組成物は、電極とのインサ−ト成形するときに、電極の隅々まで流動した後に架橋することが好ましい。抑制剤を配合すると、電極の隅々まで材料が流動する前に架橋することを防止でき、電極の隅々まで材料が流動し、その後速やかに架橋しるため、電極と材料の間に隙間などの発生も抑制でき、電極との接着力にも優れ、シ−ル性能がより向上するため、特に燃料電池シール用には好適である。
【００６０】
［その他の成分］
本発明に係る燃料電池シール部品用重合体組成物は、架橋重合体成形体あるいは架橋重合体発泡成形体のような架橋物として用いた場合に最もその特性を発揮することができる。
【００６１】
本発明に係る燃料電池シール部品用重合体組成物中に、意図する架橋物の用途等に応じて、従来公知のゴム補強剤、無機充填剤、老化防止剤、加工助剤、加硫促進剤、有機過酸化物、架橋助剤、発泡剤、発泡助剤、着色剤、分散剤、難燃剤などの添加剤を、本発明の目的を損なわない範囲で配合することができる。
【００６２】
上記ゴム補強剤は、架橋（加硫）ゴムの引張強度、引き裂き強度、耐摩耗性などの機械的性質を高める効果がある。このようなゴム補強剤としては、具体的には、ＳＲＦ、ＧＰＦ、ＦＥＦ、ＨＡＦ、ＩＳＡＦ、ＳＡＦ、ＦＴ、ＭＴ等のカーボンブラック、シランカップリング剤などにより表面処理が施されているこれらのカーボンブラック、微粉ケイ酸、シリカなどが挙げられる。
【００６３】
シリカの具体例としては、煙霧質シリカ、沈降性シリカなどが挙げられる。これらのシリカは、ヘキサメチルジシラザン、クロロシラン、アルコキシシラン等の反応性シランあるいは低分子量のシロキサン等で表面処理されていてもよい。また、これらシリカの比表面積（ＢＥＴ法）は、好ましくは１０ｍ２／ｇ以上、より好ましくは３０〜５００ｍ２／ｇである。
【００６４】
これらのゴム補強剤の種類および配合量は、その用途により適宜選択できるが、ゴム補強剤の配合量は通常、ビニル基を含有する有機重合体（ただしエチレン・α−オレフィン・非共役ジエン共重合体は除く）［Ａ］１００重量部に対して、最大３００重量部、好ましくは最大２００重量部である。
【００６５】
上記無機充填剤としては、具体的には、軽質炭酸カルシウム、重質炭酸カルシウム、タルク、クレーなどが挙げられる。
【００６６】
これらの無機充填剤の種類および配合量は、その用途により適宜選択できるが、無機充填剤の配合量は通常、有機重合体（ただしエチレン・α−オレフィン・非共役ジエン共重合体は除く）［Ａ］１００重量部に対して、最大３００重量部、好ましくは最大２００重量部である。
【００６７】
また本発明の燃料電池シール部品用重合体組成物においては、可塑剤を含有しないか、または、可塑剤の含有割合が有機重合体（ただしエチレン・α−オレフィン・非共役ジエン共重合体は除く）［Ａ］）１００重量部に対して２０重量部以下であることが望ましい。
可塑剤を添加する場合の好ましい範囲は有機重合体（ただしエチレン・α−オレフィン・非共役ジエン共重合体は除く）［Ａ］）１００重量部に対して１５重量部以下、さらに好ましくは１０重量部以下、より好ましくは５重量部以下、さらに好ましくは３重量部以下、特に好ましくは１重量部以下、とりわけ好ましくは０．１重量部以下、中でも好ましくは０．０１重量部以下である。この範囲にあれば耐抽出性が良好であるので、燃料ガスとのコンタミを起こすなどが無く、燃料効率が高い燃料電池を提供できる。本発明では実質的に可塑剤を有しないことが好ましい。これは可塑剤の添加が行われていないこと、あるいは行われていても０．０１重量％以下であるころを意味する。
上記可塑剤としては、通常ゴムに使用される可塑剤を用いることができる。
【００６８】
具体的には、プロセスオイル、潤滑油、パラフィン、流動パラフィン、石油アスファルト、ワセリン等の石油系可塑剤；
コールタール、コールタールピッチ等のコールタール系可塑剤；
ヒマシ油、アマニ油、ナタネ油、ヤシ油等の脂肪油系可塑剤；
トール油；
サブ；
蜜ロウ、カルナウバロウ、ラノリン等のロウ類；
リシノール酸、パルミチン酸、ステアリン酸バリウム、ステアリン酸カルシウム、ラウリン酸亜鉛等の脂肪酸および脂肪酸塩；
石油樹脂、アタクチックポリプロピレン、クマロンインデン樹脂等の合成高分子物質を挙げることができる。中でも石油系可塑剤が好ましく用いられ、特にプロセスオイルが好ましく用いられる。
【００６９】
上記老化防止剤としては、たとえばアミン系、ヒンダードフェノール系、またはイオウ系老化防止剤などが挙げられるが、これらの老化防止剤は、上述したように、本発明の目的を損なわない範囲で用いられる。
本発明で用いられるアミン系老化防止剤としては、ジフェニルアミン類、フェニレンジアミン類などが挙げられる。
【００７０】
ジフェニルアミン類としては、具体的には、ｐ−　（ｐ−　トルエン・スルホニルアミド）−　ジフェニルアミン、４，４’−　（α，α−ジメチルベンジル）ジフェニルアミン、４，４’−　ジオクチル・ジフェニルアミン、ジフェニルアミンとアセトンとの高温反応生成物、ジフェニルアミンとアセトンとの低温反応生成物、ジフェニルアミンとアニリンとアセトンとの低温反応物、ジフェニルアミンとジイソブチレンとの反応生成物、オクチル化ジフェニルアミン、ジオクチル化ジフェニルアミン、ｐ，ｐ’−　ジオクチル・ジフェニルアミン、アルキル化ジフェニルアミンなどが挙げられる。
【００７１】
フェニレンジアミン類としては、具体的には、Ｎ，Ｎ’−　ジフェニル−ｐ−フェニレンジアミン、ｎ−　イソプロピル−Ｎ’−フェニル−ｐ−フェニレンジアミン、Ｎ，Ｎ’−　ジ−２−　ナフチル−ｐ−フェニレンジアミン、Ｎ−シクロヘキシル−Ｎ’−フェニル−ｐ−フェニレンジアミン、Ｎ−フェニル−Ｎ’−（３−メタクリロイルオキシ−２−　ヒドロキシプロピル）−ｐ−フェニレンジアミン、Ｎ，Ｎ’−　ビス（１−メチルヘプチル）−ｐ−フェニレンジアミン、Ｎ，Ｎ’−　ビス（１，４−ジメチルペンチル）−ｐ−フェニレンジアミン、Ｎ，Ｎ’−　ビス（１−エチル−３−　メチルペンチル）−ｐ−フェニレンジアミン、Ｎ−（１，３−ジメチルブチル）−Ｎ’−フェニル−ｐ−フェニレンジアミン、フェニルヘキシル−ｐ−フェニレンジアミン、フェニルオクチル−ｐ−フェニレンジアミン等のｐ−　フェニレンジアミン類などが挙げられる。
【００７２】
これらの中でも、特に４，４’−（α，α−ジメチルベンジル）ジフェニルアミン、Ｎ，Ｎ’−　ジ−２−　ナフチル−ｐ−フェニレンジアミンが好ましい。
これらの化合物は、単独で、あるいは２種以上組み合わせて用いることができる。
【００７３】
本発明で用いられるヒンダードフェノール系老化防止剤としては、具体的には、
（１）１，１，３−トリス−（２−メチル−４−ヒドロキシ−５−ｔ−ブチルフェニル）ブタン、
（２）４，４’−　ブチリデンビス−（３−メチル−６−ｔ−ブチルフェノール）、
（３）２，２−チオビス（４−メチル−６−ｔ−ブチルフェノール）、
（４）７−オクタデシル−３−（４’−ヒドロキシ−３’，５’−ジ−ｔ−ブチルフェニル）プロピオネート、
（５）テトラキス−［メチレン−３−（３’，５’−ジ−ｔ−ブチル−４’−ヒドロキシフェニル）プロピオネートメタン、
（６）ペンタエリスリトール−　テトラキス［３−（３，５−ジ−ｔ−　ブチル−４−ヒドロキシフェニル）プロピオネート］、
（７）トリエチレングリコール−ビス［３−（３−ｔ−ブチル−５−メチル−４−ヒドロキシフェニル）プロピオネート］、
（８）１，６−ヘキサンジオール−ビス［３−（３，５−ジ−ｔ−ブチル−４−ヒドロキシフェニル）プロピオネート］、
（９）２，４−ビス（ｎ−オクチルチオ）−６−（４−ヒドロキシ−３，５−　ジ−ｔ−　ブチルアニリノ）−１，３，５−　トリアジン、
（１０）トリス−（３，５−ジ−ｔ−ブチル−４−ヒドロキシベンジル）−イソシアヌレート、
（１１）２，２−チオ−ジエチレンビス［３−（３，５−ジ−ｔ−ブチル−４−ヒドロキシフェニル）プロピオネート］、
（１２）Ｎ，Ｎ’−　ヘキサメチレンビス（３，５−ジ−ｔ−ブチル−４−ヒドロキシ）−ヒドロシンナアミド、
（１３）２，４−ビス［（オクチルチオ）メチル］−ｏ−クレゾール、
（１４）３，５−ジ−ｔ−ブチル−４−ヒドロキシベンジル−ホスホネート−ジエチルエステル、
（１５）テトラキス［メチレン（３，５−ジ−ｔ−　ブチル−４−　ヒドロキシヒドロシンナメイト）］メタン、
（１６）オクタデシル−３−（３，５−ジ−ｔ−ブチル−４−ヒドロキシフェニル）プロピオン酸エステル、
（１７）３，９−ビス［２−｛３−（３−ｔ−ブチル−４−　ヒドロキシ−５−　メチルフェニル）プロピオニルオキシ｝−１，１−ジメチルエチル］−２，４−８，１０−テトラオキサスピロ［５，５］ウンデカン
などを挙げることができる。中でも、特に（５）、（１７）のフェノール化合物が好ましい。
【００７４】
本発明で用いられるイオウ系老化防止剤としては、通常ゴムに使用されるイオウ系老化防止剤が用いられる。
具体的には、２−メルカプトベンゾイミダゾール、２−メルカプトベンゾイミダゾールの亜鉛塩、２−メルカプトメチルベンゾイミダゾール、２−メルカプトメチルベンゾイミダゾールの亜鉛塩、２−メルカプトメチルイミダゾールの亜鉛塩等のイミダゾール系老化防止剤；
ジミリスチルチオジプロピオネート、ジラウリルチオジプロピオネート、ジステアリルチオジプロピオネート、ジトリデシルチオジプロピオネート、ペンタエリスリトール−テトラキス−（β−ラウリル−チオプロピオネート）等の脂肪族チオエーテル系老化防止剤などを挙げることができる。これらの中でも、特に２−メルカプトベンゾイミダゾール、２−メルカプトベンゾイミダゾールの亜鉛塩、２−メルカプトメチルベンゾイミダゾール、２−メルカプトメチルベンゾイミダゾールの亜鉛塩、ペンタエリスリトール−　テトラキス−（β−　ラウリル−　チオプロピオネート）が好ましい。
【００７５】
上記の加工助剤としては、通常のゴムの加工に使用される化合物を使用することができる。具体的には、リシノール酸、ステアリン酸、パルチミン酸、ラウリン酸等の高級脂肪酸；ステアリン酸バリウム、ステアリン酸亜鉛、ステアリン酸カルシウム等の高級脂肪酸の塩；リシノール酸、ステアリン酸、パルチミン酸、ラウリン酸等の高級脂肪酸のエステル類などが挙げられる。
【００７６】
このような加工助剤は、通常、ビニル基を含有する有機重合体（ただしエチレン・α−オレフィン・非共役ジエン共重合体は除く）［Ａ］１００重量部に対して、１０重量部以下、好ましくは５重量部以下の割合で用いられるが、要求される物性値に応じて適宜最適量を決定することが望ましい。
本発明においては、上述した触媒［Ｃ］の他に有機過酸化物を使用して、付加架橋とラジカル架橋の両方を行なってもよい。有機過酸化物は、ビニル基を含有する有機重合体（ただしエチレン・α−オレフィン・非共役ジエン共重合体は除く）［Ａ］１００重量部に対し、０．１〜１０重量部程度の割合で用いられる。有機過酸化物としては、ゴムの架橋の際に通常使用されている従来公知の有機過酸化物を使用することができる。
【００７７】
また、有機過酸化物を使用するときは、架橋助剤を併用することが好ましい。
架橋助剤としては、具体的には、イオウ；ｐ−　キノンジオキシム等のキノンジオキシム系化合物；ポリエチレングリコールジメタクリレート等のメタクリレート系化合物；ジアリルフタレート、トリアリルシアヌレート等のアリル系化合物；マレイミド系化合物；ジビニルベンゼンなどが挙げられる。このような架橋助剤は、使用する有機過酸化物１モルに対して０．５〜２モル、好ましくは約等モルの量で用いられる。
【００７８】
また、本発明に係る架橋可能な重合体組成物中に、本発明の目的を損なわない範囲で、公知の他のゴムとブレンドして用いることができる。
このような他のゴムとしては、エチレン・α−オレフィン・非共役ポリエン共重合体、天然ゴム（ＮＲ）、イソプレンゴム（ＩＲ）などのイソプレン系ゴム、ブタジエンゴム（ＢＲ）、スチレン−ブタジエンゴム（ＳＢＲ）、アクリロニトリル−ブタジエンゴム（ＮＢＲ）、クロロプレンゴム（ＣＲ）などの共役ジエン系ゴムを挙げることができる。
【００７９】
［重合体組成物および燃料電池シール部品の調製］
上述したように、本発明に係る燃料電池シール部品用重合体組成物は、架橋成形体として用いた場合に最もその特性を発揮することができる。したがって、本発明に係る燃料電池シール部品、例えば、燃料電池セルシール部品は、通常は架橋成形体である。
【００８０】
本発明に係る燃料電池シール部品用重合体組成物から架橋成形体を製造するには、通常一般のゴムを加硫（架橋）するときと同様に、未架橋の配合体、例えば配合ゴムを一度調製し、次いで、この配合体を意図する形状に成形した後に架橋を行なえばよい。
本発明の燃料電池シール部品は、例えば、固体高分子型（固体高分子電解質型）燃料電池シール部品であることが好ましい。
【００８１】
架橋方法としては、架橋剤（ＳｉＨ基含有化合物［Ｂ］）を使用して加熱する方法、または光、γ線、電子線照射による方法のどちらを採用してもよい。
【００８２】
まず、本発明に係る燃料電池シール部品用重合体組成物は、たとえば次のような方法で調製される。
すなわち、本発明に係る燃料電池シール部品用重合体組成物は、プラネタリ−ミキサ−、バンバリーミキサー、ニーダー、インターミックスのようなインターナルミキサー（密閉式混合機）類により、ビニル基を含有する有機重合体（ただしエチレン・α−オレフィン・非共役ジエン共重合体は除く）［Ａ］、ゴム補強剤、無機充填剤、軟化剤などの添加剤を好ましくは５０〜１８０℃の温度で３〜１０分間混練した後、３本ロ−ルやオープンロールのようなロール類、あるいはニーダーを使用して、ＳｉＨ基含有化合物［Ｂ］および必要に応じて触媒［Ｃ］、反応抑制剤［Ｄ］、加硫促進剤、架橋助剤を追加混合し、ロール温度１００℃以下で１〜３０分間混練することにより調製することができる。
【００８３】
また、インターナルミキサー類での混練温度が低い場合には、、ビニル基を含有する有機重合体（ただしエチレン・α−オレフィン・非共役ジエン共重合体は除く）［Ａ］、ＳｉＨ基含有化合物［Ｂ］、ゴム補強剤、無機充填剤、軟化剤などとともに、老化防止剤、着色剤、分散剤、難燃剤などを同時に混練してもよい。
上記のようにして調製された、本発明に係る燃料電池シール部品用重合体組成物は、ＬＩＭ成形機、インジェクション成形機、トランスファー成形機、プレス成形機、押出成形機、カレンダーロ−ルなどを用いる種々の成形法より、意図する形状に成形され、成形と同時にまたは成型物を加硫槽内に導入し、架橋することができる。これらの中でも、ＬＩＭ成形機は、カ−ボンやフィルムとのインサ−ト成形、ノ−バリ成形、厚薄精度、高速成形の点から目的とする燃料電池シール部品を製造するに好適である。また、射出成形や圧縮成形も好適である。架橋条件としては、５０〜２７０℃の温度で０．５〜３０分間加熱するか、あるいは前記した方法により光、γ線、電子線を照射することにより架橋ゴム成形体、すなわち本発明においては燃料電池シール部品が得られる。また、常温で架橋することもできる。
【００８４】
この架橋の段階は金型を用いてもよいし、また金型を用いないで架橋を実施してもよい。金型を用いない場合は成形、架橋の工程は通常連続的に実施される。加硫槽における加熱方法としては、熱空気、ガラスビーズ流動床、ＵＨＦ（極超短波電磁波）、スチームなどの加熱槽を用いることができる。
本発明に係る重合体組成物を特にＬＩＭ成形に適用する場合は、ＳｉＨ基含有化合物［Ｂ］と触媒［Ｃ］とを別々に配合した液状重合体組成物を調製することが望ましい。
【００８５】
すなわち、材料の粘度により適宜使い分けるが、バンバリーミキサー、ニーダー、インターミックスのようなインターナルミキサー（密閉式混合機）類やプラネタリミキサーのような攪拌機により、ビニル基を含有する有機重合体（ただしエチレン・α−オレフィン・非共役ジエン共重合体は除く）［Ａ］、ゴム補強剤、無機充填剤、軟化剤などの添加剤およびＳｉＨ基含有化合物［Ｂ］を３〜１０分間混練し、液状重合体組成物（１）を調製する。さらに、ビニル基を含有する有機重合体（ただしエチレン・α−オレフィン・非共役ジエン共重合体は除く）［Ａ］、ゴム補強剤、無機充填剤、軟化剤などの添加剤および触媒［Ｃ］、必要に応じて反応抑制剤［Ｄ］を３〜１０分混練し、液状重合体組成物（２）を調製する。続いて、これら液状重合体組成物（１）と液状重合体組成物（２）とをＬＩＭ成形装置に直接接続可能な専用のペール缶または直接接続可能なカートリッジに入れ、計量、混合装置を経てＬＩＭ成形を施すことにより、目的とする燃料電池シール部品を得ることができる。
【００８６】
したがって、ビニル基を含有する有機重合体（ただしエチレン・α−オレフィン・非共役ジエン共重合体は除く）［Ａ］、ＳｉＨ基含有化合物［Ｂ］および必要に応じてゴム補強剤、無機充填剤、軟化剤などの添加剤とからなる、重合体組成物（１）と、ビニル基を含有する有機重合体（ただしエチレン・α−オレフィン・非共役ジエン共重合体は除く）［Ａ］、および触媒［Ｃ］、必要に応じて反応抑制剤［Ｄ］、さらに必要に応じてゴム補強剤、無機充填剤、軟化剤などの添加剤とからなる、液状重合体組成物（２）とを混合してＬＩＭ成形する、という方法が、本発明の燃料電池用シール部品の製造方法の好ましい一態様である。
【００８７】
よって、ビニル基を含有する有機重合体（ただしエチレン・α−オレフィン・非共役ジエン共重合体は除く）［Ａ］、ＳｉＨ基含有化合物［Ｂ］および必要に応じてゴム補強剤、無機充填剤、軟化剤などの添加剤とからなる重合体組成物（１）、あるいはビニル基を含有する有機重合体（ただしエチレン・α−オレフィン・非共役ジエン共重合体は除く）［Ａ］、および触媒［Ｃ］、必要に応じて反応抑制剤［Ｄ］、さらに必要に応じてゴム補強剤、無機充填剤、軟化剤などの添加剤とからなる重合体組成物（２）、さらには重合体組成物（１）と重合体組成物（２）とからなる材料は、燃料電池用シール部品用材料、特にＬＩＭ成形に用いられる材料として好適である。
【００８８】
【発明の効果】
本発明に係る燃料電池シール部品用重合体組成物は、架橋速度が速く、生産性（高速成形性）に優れ、耐圧縮永久歪み性、ガスバリヤ性（水素、酸素、水蒸気、等が８０℃から１２０℃程度の環境で低透過性であること）、耐熱性、耐酸性（硫酸等のスルホン酸に対する耐性があること）、耐冷却水（ＬＬＣ等）性などの特性に優れる燃料電池シール部品を提供することができる。
【００８９】
本発明に係る燃料電池シール部品は、上記重合体組成物から調製されるので、生産性に優れ、耐圧縮永久歪み性、ガスバリヤ性、耐酸性、耐冷却水性、などの特性に優れている。
本発明にかかる燃料電池シール部品の製造方法によれば、耐圧縮永久歪み性、ガスバリヤ性、耐熱性、耐酸性、耐冷却水性などの特性に優れる燃料電池シール部品を高速で生産できる。
【００９０】
【実施例】
以下、本発明を実施例により説明するが、本発明は、これら実施例により何ら限定されるものではない。
なお、実施例、比較例で用いた共重合体［Ａ］の組成、ヨウ素価、極限粘度［η］などは、次のような方法で測定ないし計算により求めた。
（１）共重合体［Ａ］の組成
共重合体［Ａ］の組成は^１３Ｃ−ＮＭＲ法で測定した。
（２）共重合体［Ａ］のヨウ素価
共重合体［Ａ］のヨウ素価は、滴定法により求めた。
（３）数平均分子量
ビニル基を含有する有機重合体［Ａ］の数平均分子量は、ＧＰＣを用いて測定した。
ＧＰＣには、カラムに東ソ−（株）製のＧＭＨ−ＨＴ、ＧＭＨ−ＨＴＬを用い、溶媒にはオルソジクロロベンゼンを用いた。）
【００９１】
［実施例１］
ビニル基を含むポリイソブチレン（Ａ−１）［鐘淵化学（株）製、商品名　エピオン６００Ａ　分子量＝２００００］１００重量部と、シリカ［商品名　ニプシルＶＮ３、日本シリカ工業（株）製］３０重量部を容量２リットルのプラネタリーミキサー［（株）井上製作所製、商品名：ＰＬＭ−２型］で混練し、配合物（Ｉ−１）を得た。
【００９２】
次に、この配合物（Ｉ−１）１３０重量部に、Ｃ６Ｈ５−Ｓｉ（ＯＳｉ（ＣＨ３）２Ｈ）３で示されるＳｉＨ基含有化合物（信越化学株式会社製　商品名Ｘ−９３−９１６）［Ｂ］（架橋剤）４重量部、反応抑制剤［Ｄ］として１−エチニル−１−シクロヘキサノール０．１重量部（日進化学株式会社）、触媒［Ｃ］として塩化白金酸濃度２重量％のイソプロピルアルコール溶液（信越化学株式会社製　商品名ＰＬ−２）０．１重量部を加えて、３インチφの３本ロ−ル［（株）小平製作所製、商品名３本ロールミル］で３回混練したのちに、５０トンプレス成形機を用いて１２０℃で６分間加圧し、厚み２ｍｍの架橋ゴムシートを調製した。
【００９３】
上記のようにして得られたシートを用い、物性試験を下記（４）から（８）の方法に従って行なった。
（４）引張試験
ＪＩＳ　Ｋ６２５１に従って、測定温度２３℃、引張速度５００ｍｍ／分の条件で引張試験を行ない、架橋シートの破断時の引張強度ＴＢ　と伸びＥＢ　を測定した。
（５）ガスバリヤ性
ＪＩＳ　Ｋ　７１２６に従って、下記の条件でガスバリヤ試験を行ない、酸素透過係数を測定した。
（測定条件）
酸素１００％、試験温度２３℃、湿度０％。
（試験機）
東洋精機（株）製、差圧法ガス透過試験機。
（６）耐酸性
ＪＩＳ　Ｋ　６２５８（１９９３）に従って、下記の条件で酸性溶液へ浸漬試験を行った後、引張伸び、強度、及び体積変化率を測定し、それぞれの変化率（硬さは変化値）を求めた。
（浸漬条件）
２５℃、１６８時間。
（酸性溶液）
塩酸３５重量％濃度溶液および硫酸７０重量％濃度溶液を用いた。
【００９４】
（７）抽出性
ＪＩＳ　Ｋ　６２５８（１９９３）に従って、下記の条件でｎヘキサン溶液へ浸漬試験を行った後、体積変化率を測定し、それぞれの変化率（硬さは変化値）を求めた。
（浸漬条件）
２５℃、１６８時間。
抽出物が少なければ、燃料電池の反応ガス中に混入することもほとんどなく、燃料効率を低下させる可能性も少ない。
（８）電極汚染性
ＪＩＳ　Ｋ　６２６７（１９９６）に従って、カ−ボン電極に架橋ゴムを接触し、汚染性の評価を目視にて実施した。
（汚染条件）
１００℃×１６８時間
○：電極に汚染物質が付着しない
△：電極に汚染物質が付着する。
×：電極に汚染物質が多量に付着する。
電極に汚染物質が付着しなければ、接点不良の発生も少なく、燃料電池としての機能が十分に果たせる。
［実施例２］
実施例１において、実施例１で用いたシリカ３０重量部の代わりに、表１に示すようにカ−ボンブラック［東海カーボン（株）製、商品名　シーストＧ−１１６］を３０重量部用いた以外は、実施例１と同様にして、架橋ゴムシートを得た。
得られた架橋ゴムシートについて、引張試験、ガスバリヤ試験、耐酸性試験を行なった。その結果を表２に示す。
【００９５】
［実施例３］
実施例２において、表１に示すように、実施例２で用いたビニル基を含有するポリイソブチレン（Ａ−１）の代わりに、ビニル基を含有する有機重合体ポリイソブチレン［鐘淵化学（株）製、商品名　エピオン４００Ａ　数平均分子量＝１００００　　］（Ａ−２）を用いた以外は、実施例２と同様にして、架橋ゴムシートを得た。
【００９６】
得られた架橋ゴムシートについて、引張試験、ガスバリヤ試験、耐酸性試験を行なった。その結果を表２に示す。
【００９７】
［実施例４］
実施例２において、表１に示すように、実施例２で用いたビニル基を含有するポリイソブチレン（Ａ−１）の代わりに、ビニル基を含有するポリイソブチレン［鐘淵化学（株）製、商品名　エピオン２００Ａ　数平均分子量＝５０００］（Ａ−３）を用いた以外は、実施例２と同様にして、架橋ゴムシートを得た。得られた架橋ゴムシートについて、引張試験、ガスバリヤ試験、耐酸性試験を行なった。その結果を表２に示す。
【００９８】
［実施例５］
実施例２において、表１に示すように、実施例２で用いたビニル基を含有するポリイソブチレン（Ａ−１）の代わりに、ビニル基を含有するポリプロピレングリコ−ル［鐘淵化学（株）製、商品名　ＭＳポリマ−２０３Ａ　数平均分子量＝８０００］（（Ａ−４）を用いた以外は、実施例２と同様にして、架橋ゴムシートを得た。得られた架橋ゴムシートについて、引張試験、ガスバリヤ試験、耐酸性試験を行なった。その結果を表２に示す。
【００９９】
［実施例６］
実施例２において、表１に示すように、実施例２で用いたビニル基を含有するポリイソブチレン（Ａ−１）の代わりに、ビニル基を含有するポリプロピレングリコ−ル［鐘淵化学（株）製、商品名　ＭＳポリマ−２０３Ａ　数平均分子量＝９０００］（（Ａ−５）を用いた以外は、実施例２と同様にして、架橋ゴムシートを得た。
得られた架橋ゴムシートについて、引張試験、ガスバリヤ試験、耐酸性試験を行なった。その結果を表２に示す。
【０１００】
［実施例７］
実施例３において、表１に示すように、実施例３で用いた１−エチニル−１−シクロヘキサノ−ル（Ｅ）の代わりに、ジビニルジシロキサン（Ｅ）を用いた以外は、実施例３と同様にして、架橋ゴムシートを得た。得られた架橋ゴムシートについて、引張試験、ガスバリヤ試験、耐酸性試験を行なった。その結果を表２に示す。
【０１０１】
［比較例１］
実施例２において、表１に示すように、実施例２で用いたビニル基を含有するポリイソブチレン（Ａ−１）の代わりに、エチリデン基を含有するＥＰＤＭ（Ａ−３）を用いた以外は、実施例２と同様にして、架橋ゴムシートを得ようとしたが架橋反応が非常に遅く架橋ゴムシ−トを得ることは出来なかった。
【０１０２】
［実施例８］
実施例３において、表１に示すように、可塑剤（出光化学製、ＰＡＯ５００４）を２３重量部加えた以外は、実施例３と同様にして、架橋ゴムシートを得た。得られた架橋ゴムシートについて、引張試験、ガスバリヤ試験、耐酸性試験を行なった。その結果を表２に示す。
【０１０３】
得られた架橋ゴムシートについて、引張試験、ガスバリヤ試験、耐酸性試験、抽出性、電極汚染性を行なった。その結果を表２に示す。
【０１０４】
【表１】

【０１０５】
【表２】

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a polymer composition for a fuel cell seal part, a fuel cell seal part, a method for producing a fuel cell seal part, and a fuel cell. More specifically, the present invention relates to a high crosslinking rate, excellent productivity, and compression set resistance. Composition for fuel cell seal parts, excellent in properties such as gas barrier property and acid resistance, fuel cell seal parts obtained from the composition, method for producing fuel cell seal parts using the composition, and the fuel The present invention relates to a fuel cell having a battery seal part.
[0002]
TECHNICAL BACKGROUND OF THE INVENTION
A fuel cell is an efficient and clean power generation system that extracts electricity directly by the reverse reaction of water electrolysis, that is, a chemical reaction between hydrogen and oxygen, and has recently attracted attention as a new energy system for automobiles and homes. Have been. Low cost materials with excellent heat resistance, acid resistance, gas permeability resistance and high-speed moldability are required for cell seal parts of fuel cells, etc. Butyl rubber is used for gas permeability resistance, and silicone rubber is used for heat resistance and moldability, but ordinary materials are insufficient for high-speed moldability requirements. A method using LIM (Liquid Injection Molding) molding using silicone rubber of the above is considered.
[0003]
However, although silicone rubber is excellent in heat resistance and high-speed moldability, it is inferior in acid resistance and gas permeation resistance.Current fuel cells have low power generation performance, and improvement studies are underway. In the future, as the power generation performance is improved, the reaction temperature inside the cell and the like tends to increase. Therefore, higher temperature performance is also required for the sealing material.
JP-A-2001-240756 discloses an organic polymer containing at least one hydrosilyl-reactive alkenyl group in a molecule, a curing agent containing at least two hydrosilyl groups in a molecule, a hydrosilyl catalyst, and vinylsiloxane. It is disclosed that a curable composition comprising a compound having a skeleton can be expected to be used as a sealing material for a fuel cell. However, when the inventors of the present application performed additional tests, it was found that there was a problem of poor extractability and electrode contamination.
[0004]
Therefore, the present inventors have conducted intensive studies and have studied a specific organic polymer [A] containing a vinyl group, a specific organopolysiloxane [B], a compound [B] containing a SiH group, and a catalyst [ C] and a polymer composition comprising the reaction inhibitor [D] are excellent in high-speed molding and suitable for fuel cell seal parts having excellent heat resistance, acid resistance and gas permeability resistance. The invention has been completed.
[0005]
It should be noted that WO / 00/55251 discloses an ethylene / α- olefin having a constitutional unit derived from at least one kind of norbornene compound containing a terminal vinyl group, which is not used for a fuel cell seal part, but is represented by a specific general formula. A polymer composition for a hermetic seal packing capable of cross-linking a specific polymer composition, comprising a non-conjugated polyene random copolymer rubber and a SiH group-containing compound having at least two SiH groups in one molecule. An invention is disclosed.
[0006]
[Object of the invention]
An object of the present invention is to solve the problems associated with the prior art as described above, and to provide a high-speed fuel cell sealing component having excellent heat resistance, acid resistance, and gas permeability resistance (gas barrier property). Provided are a polymer composition having excellent moldability, a fuel cell seal component obtained by crosslinking the polymer composition, a method for producing the fuel cell seal component, and a fuel cell having the fuel cell seal component. The purpose is.
[0007]
Summary of the Invention
The polymer composition for a fuel cell seal part according to the present invention,
It is characterized by comprising an organic polymer [A] containing a vinyl group (excluding an ethylene / α-olefin / non-conjugated polyene copolymer) and a compound [B] containing a SiH group.
[0008]
The SiH group-containing compound [B] of the present invention is used in an amount of 0.1 parts by weight based on 100 parts by weight of the vinyl group-containing organic polymer [A] (excluding the ethylene / α-olefin / non-conjugated polyene copolymer). Preferably, it is contained in an amount of up to 100 parts by weight.
[0009]
In addition, the SiH group-containing compound [B] of the present invention is obtained by adding a vinyl group-containing organic polymer [A] (excluding an ethylene / α-olefin / non-conjugated polyene copolymer) to one vinyl group. It is preferable to contain 0.2 to 10 hydrogen atoms bonded to silicon atoms.
[0010]
Further, the polymer composition of the present invention comprises, in addition to the vinyl group-containing organic polymer [A] (excluding the ethylene / α-olefin / non-conjugated polyene copolymer) and the SiH group-containing compound [B], It may contain a catalyst [C] if necessary and further a reaction inhibitor [D] if necessary.
[0011]
In addition, the polymer composition of the present invention contains an organic polymer [A] containing no plasticizer or having a plasticizer content of a vinyl group (however, an ethylene / α-olefin / non-conjugated polyene copolymer). Is preferably 20 parts by weight or less per 100 parts by weight.
[0012]
A fuel cell seal part of the present invention is characterized by being formed by molding the polymer composition described in any of the above.
[0013]
The method for producing a fuel cell seal component of the present invention is characterized in that the polymer composition for a fuel cell seal described above is crosslinked.
[0014]
A fuel cell according to the present invention includes the above-described fuel cell seal component.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the polymer composition for a fuel cell seal component according to the present invention and its use will be specifically described.
[Polymer composition for fuel cell seal parts]
The polymer composition for a fuel cell seal component according to the present invention is an organic polymer having a vinyl group (excluding an ethylene / α-olefin / non-conjugated polyene copolymer) [A];
It comprises a SiH group-containing compound [B], preferably a SiH group-containing compound [B] having at least two or more SiH groups in one molecule, and optionally a catalyst [C] and, if necessary, a reaction inhibitor [ D] is added. The polymer composition for a fuel cell seal component is preferably a crosslinkable composition.
[0016]
[Organic polymer containing vinyl group (excluding ethylene / α-olefin / non-conjugated polyene copolymer) [A]]
The organic polymer containing a vinyl group used in the present invention is not particularly limited as long as it is an organic polymer containing at least one vinyl group in a molecule, and those having various main chain skeletons are used. be able to. However, it is desirable that the organic polymer is not an ethylene / α-olefin / non-conjugated polyene copolymer. If specifically exemplified, polyoxyethylene, polyoxypropylene, polyoxytetramethylene, polyether polymers such as polyoxyethylene-polyoxypropylene copolymer, terephthalic acid, isophthalic acid, adipic acid and the like Polyisobutylene, polyester copolymer obtained by condensation of dibasic acid or its anhydride with glycols such as ethylene glycol, propylene glycol, neopentyl glycol and the like or ring-opening polymerization of lactones , Copolymers of isobutylene and isopropylene, polychloroprene, polyisoprene, copolymers of isoprene and butadiene, acrylonitrile, styrene, etc., polybutadienes, copolymers of butadiene and styrene, copolymers of acrylonitrile, etc., polyisoprene, polybutadiene , Isoprene or butyl Polymers obtained by hydrogenating copolymers of dienes with acrylonitrile, styrene and the like, polyacrylates, ethyl acrylate and butyl acrylate obtained by radical polymerization of monomers such as ethyl acrylate and butyl acrylate Acrylate-based copolymers of acrylates such as acrylates with vinyl acetate, acrylonitrile, methyl methacrylate, styrene, etc .; graft polymers obtained by polymerizing vinyl monomers in the organic polymers; polysulfide-based Examples of the polymer include a polycarbonate-based polymer produced by condensation polymerization of bisphenol A and carbonyl chloride. As the organic polymer, for example, a polymer having a structure containing at least one carbon atom in a main chain constituent part in a repeating unit is used. Further, an organic polymer having no carbon-carbon double bond in the main chain of the organic polymer is more preferably used, for example.
[0017]
Among the above organic polymers [A], polyester-based polymers, polyether-based polymers, acrylate-based polymers, acrylate-based copolymers, and hydrocarbon-based polymers (A1) are preferable, Above all, a hydrocarbon polymer (A1) is preferred, and among the hydrocarbon polymers, polyisobutylene containing a vinyl group is preferred.
[0018]
The number average molecular weight of the organic polymer [A] (excluding the ethylene / α-olefin / non-conjugated polyene copolymer) [A] used in the present invention is usually 500 to 100,000, preferably 500 to 50,000, It is preferably from 1,000 to 20,000, more preferably from 2,000 to 10,000, particularly preferably from 2,000 to 9000, particularly preferably from 3,000 to 6,000.
[0019]
When the number average molecular weight does not exceed the above upper limit, the fluidity is particularly good. Since it is not necessary to add a plasticizer for improvement, extraction resistance is good, which leads to providing a fuel cell with high fuel efficiency. If the lower limit is within this range, the mechanical properties are excellent and the function as a fuel cell seal material can be sufficiently achieved.
[0020]
In the organic polymer [A] (excluding the ethylene / α-olefin / non-conjugated polyene copolymer) [A] used in the present invention, the vinyl content is usually 1.1 or more, preferably 2 to 2 in the molecule. The number is 10, more preferably 2 to 5, more preferably 2 to 3, and particularly preferably 2. Further, the vinyl group may be at a side chain or at a terminal in the molecule, but is preferably at a terminal. The molecular structure may be a linear type or a branched type, but the linear type is preferred.
[0021]
The vinyl group content can be analyzed by NMR or the like. Specific examples are described in Macromolecules, 28, p437-p443 (1995). Further, for example, when a polyene containing a vinyl group is copolymerized, the vinyl group of the polyolefin can be specified by comparing the resulting polyolefin with the used polyene as a model compound. When only the vinyl group is present in the organic polymer, it can be determined by an iodine titration method or the like.
[0022]
[SiH group-containing compound [B]]
The SiH group-containing compound [B] used in the present invention reacts with an organic polymer [A] containing a vinyl group other than EPDM, and acts as a crosslinking agent. The SiH group-containing compound [B] is not particularly limited in its molecular structure, and can be used, for example, in a conventionally manufactured resinous material having a linear, cyclic, branched or three-dimensional network structure. It is preferable that one molecule contains at least two hydrogen atoms directly bonded to silicon atoms, that is, SiH groups.
[0023]
As the SiH group-containing compound [B], the following general composition formula is usually used.
R⁴ _bH_cSiO_{(4-bc) / 2}
Can be used.
In the above general composition formula, R⁴Is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, particularly 1 to 8 carbon atoms, excluding an aliphatic unsaturated bond. In addition to the alkyl group exemplified for R1 in the general formula [I], a phenyl group and a halogen-substituted alkyl group such as a trifluoropropyl group can be exemplified. Among them, a methyl group, an ethyl group, a propyl group, a phenyl group and a trifluoropropyl group are preferred, and a methyl group and a phenyl group are particularly preferred.
[0024]
B is 0 ≦ b <3, preferably 0.6 <b <2.2, particularly preferably 1.5 ≦ b ≦ 2, and c is 0 <c ≦ 3, preferably 0.002. .Ltoreq.c <2, particularly preferably 0.01.ltoreq.c.ltoreq.1, and b + c is 0 <b + c.ltoreq.3, preferably 1.5 <b + c.ltoreq.2.7.
[0025]
The SiH group-containing compound [B] is an organohydrogenpolysiloxane having preferably 2 to 1000, particularly preferably 2 to 300, and most preferably 4 to 200 silicon atoms in one molecule. In general,
Siloxane oligomers such as 1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethyltetracyclosiloxane, 1,3,5,7,8-pentamethylpentacyclosiloxane;
Methyl hydrogen polysiloxane blocked with trimethylsiloxy groups at both ends of molecular chains, dimethylsiloxane / methylhydrogensiloxane copolymer blocked with trimethylsiloxy groups at both ends of molecular chains, methyl hydrogen polysiloxane blocked with silanol groups at both ends of molecular chains, both ends of molecular chains Silanol group-blocked dimethyl siloxane / methyl hydrogen siloxane copolymer, molecular chain both ends dimethyl hydrogen siloxy group blocked dimethyl polysiloxane, molecular chain both ends dimethyl hydrogen siloxy group blocked methyl hydrogen polysiloxane, molecular chain both ends dimethyl hydro Gensiloxy-blocked dimethylsiloxane / methylhydrogensiloxane copolymer, R⁴ ₂(H) SiO_1/2Unit and SiO_4/2Unit, optionally R⁴ ₃SiO_1/2Unit, R⁴ ₂SiO_2/2Unit, R₄(H) SiO_2/2Unit, (H) SiO_3/2Or R⁴SiO_3/2Examples include a silicone resin that can include units.
[0026]
Examples of the methylhydrogenpolysiloxane having a trimethylsiloxy group blocked at both ends of a molecular chain include a compound represented by the following formula, and further, in the following formula, a part or all of a methyl group is an ethyl group, a propyl group, a phenyl group, a trifluoropropyl group. And the like.
(CH₃)₃SiO-(-SiH (CH₃) -O-)_d-Si (CH₃)₃
[D is an integer of 2 or more. ]
As a dimethylsiloxane / methylhydrogensiloxane copolymer having a trimethylsiloxy group-blocked molecular chain at both ends, a compound represented by the following formula, and further, in the following formula, a part or all of a methyl group is an ethyl group, a propyl group, a phenyl group, Compounds substituted with a trifluoropropyl group and the like can be mentioned.
[0027]
(CH₃)₃SiO-(-Si (CH₃)₂-O-)_e-(-SiH (CH₃) -O-)_f-Si (CH₃)₃
[E in the formula is an integer of 1 or more, and f is an integer of 2 or more. ]
Examples of the methylhydrogenpolysiloxane having silanol groups at both ends of the molecular chain include compounds represented by the following formula, and further, in the following formula, a part or all of a methyl group is an ethyl group, a propyl group, a phenyl group, a trifluoropropyl group or the like. And the like.
[0028]
HOSi (CH₃)₂O-(-SiH (CH₃) -O-)₂-Si (CH₃)₂OH
Examples of the dimethylsiloxane / methylhydrogensiloxane copolymer having silanol groups at both ends of the molecular chain include a compound represented by the following formula, and further, in the following formula, part or all of a methyl group is an ethyl group, a propyl group, a phenyl group, Compounds substituted with a trifluoropropyl group and the like can be mentioned.
[0029]
HOSi (CH₃)₂O-(-Si (CH₃)₂-O-)_e-(-SiH (CH₃) -O-)_f
-Si (CH₃)₂OH
[E in the formula is an integer of 1 or more, and f is an integer of 2 or more. ]
Examples of the dimethylpolysiloxane blocked with dimethylhydrogensiloxy groups at both ends of the molecular chain include a compound represented by the following formula, and further, in the following formula, a part or all of a methyl group is an ethyl group, a propyl group, a phenyl group, a trifluoropropyl group. And the like.
[0030]
HSi (CH₃)₂O-(-Si (CH₃)₂-O-)_e-Si (CH₃)₂H
[E in the formula is an integer of 1 or more. ]
Examples of the methyl hydrogen polysiloxane having a dimethylhydrogensiloxy group blocked at both molecular chain terminals include a compound represented by the following formula, and further, in the following formula, a part or all of a methyl group is an ethyl group, a propyl group, a phenyl group, a trifluoro group. Compounds substituted with a propyl group and the like can be mentioned.
[0031]
HSi (CH₃)₂O-(-SiH (CH₃) -O-)_e-Si (CH₃)₂H
[E in the formula is an integer of 1 or more. ]
Examples of the dimethylsiloxane / methylhydrogensiloxane copolymer having a dimethylhydrogensiloxy group-blocked dimethylhydrogensiloxy group at both ends of the molecular chain include, for example, a compound represented by the following formula. Examples thereof include compounds substituted with a phenyl group, a trifluoropropyl group, and the like.
[0032]
HSi (CH₃)₂O-(-Si (CH₃)₂-O-)_e-(-SiH (CH₃) -O-)_h
-Si (CH₃)₂H
[E and h in the formula are each an integer of 1 or more. ]
Such a compound can be produced by a known method, for example, octamethylcyclotetrasiloxane and / or tetramethylcyclotetrasiloxane, and hexamethyldisiloxane or 1,3-dihydro-1,1 which can be a terminal group. A compound containing a triorganosilyl group or a diorganohydrogensiloxy group, such as 3,3,3-tetramethyldisiloxane, at −10 ° C. in the presence of a catalyst such as sulfuric acid, trifluoromethanesulfonic acid or methanesulfonic acid; It can be easily obtained by equilibrating at a temperature of about + 40 ° C.
[0033]
When such a compound is used, the number of SiH bonds is preferably in the range of 1.1 to 100. The lower limit is not particularly limited, but is preferably 1.5 or more, more preferably 2 or more. The upper limit is not particularly limited, but is preferably 50 or less, more preferably 20 or less, further preferably 10 or less, and particularly preferably 8 or less. Specifically, an embodiment in which the number is 1.5 to 50, preferably 2 to 20, more preferably 2 to 10, and still more preferably 2 to 8 is exemplified. Examples of such compounds include the following compounds.
[0034]
Embedded image

[0035]
Embedded image

Further, the above-mentioned general composition formula ΔR⁴ _bH_cSiO_{(4-bc) / 2}
In the compound represented by the formula:⁴Is preferably a hydrocarbon group having 3 or more carbon atoms, for example, a propyl group, a butyl group and a phenyl group. Within this range, the electrode is particularly excellent in stain resistance.
For example, C₆H₅-Si (OSi (CH₃)₂H)₃And the like.
[0036]
The SiH group-containing compound [B] is used in an amount of 0.1 to 100 parts by weight based on 100 parts by weight of the vinyl group-containing organic polymer (excluding the ethylene / α-olefin / non-conjugated diene copolymer) [A]. Parts, preferably 0.1 to 75 parts by weight, more preferably 0.1 to 50 parts by weight, further preferably 0.2 to 30 parts by weight, still more preferably 0.2 to 20 parts by weight, particularly preferably 0 to 20 parts by weight. It is used in a proportion of 0.5 to 10 parts by weight, more preferably 2 to 8 parts by weight, most preferably 4 to 8 parts by weight. When the SiH group-containing compound [B] is used in a proportion within the above range, a polymer composition which can form a crosslinked rubber molded article having excellent compression set resistance, moderate crosslink density, and excellent strength properties and elongation properties. Is obtained. It is not preferable to use the SiH group-containing compound [B] in a proportion exceeding 100 parts by weight, because it is disadvantageous in terms of cost.
[0037]
In addition, the aliphatic compound contained in the organic polymer (excluding the ethylene / α-olefin / non-conjugated diene copolymer) [A] ([A] component) in which the SiH group-containing compound [B] is a vinyl group-containing organic polymer (excluding ethylene / α-olefin / non-conjugated diene copolymer) The ratio of a hydrogen atom (≡SiH group) bonded to a silicon atom to one unsaturated bond (alkenyl group, diene group, etc.) is suitably in the range of 0.2 to 10, preferably 0.7 to 5 Is appropriate. If it is 0.2 or less, a large amount of vinyl groups may remain, and the heat aging resistance may deteriorate. On the other hand, if it is 10 or more, a large amount of the unreacted SiH group-containing compound may remain to deteriorate the electrode contamination.
[0038]
[Catalyst [C]]
The catalyst [C] used as an optional component in the present invention is an addition reaction catalyst, and the alkenyl group of the organic polymer [A] component containing a vinyl group other than EPDM and the SiH of the SiH group-containing compound [B]. It promotes an addition reaction with a group (such as a hydrosilylation reaction of an alkene).
[0039]
As the catalyst [C], a catalyst for addition reaction comprising a platinum group element such as a platinum-based catalyst, a palladium-based catalyst, and a rhodium-based catalyst is usually used. In the present invention, a platinum-based catalyst is preferable. As the catalyst [C], including a platinum-based catalyst, it is desirable to use a complex of a metal belonging to Group 8 of the periodic table, particularly preferably platinum, and a compound containing a vinyl group and / or a carbonyl group.
[0040]
As the compound containing a carbonyl group, carbonyl, octal, and the like are preferable. Specific examples of complexes of these with platinum include a platinum-carbonyl complex, a platinum-octanal complex, a platinum-carbonylbutyl cyclic siloxane complex, and a platinum-carbonylphenyl cyclic siloxane complex.
As the compound containing a vinyl group, a vinyl group-containing organosiloxane is preferable. Specific examples of complexes of these with platinum include platinum-divinyltetramethyldisiloxane complex, platinum-divinyltetraethyldisiloxane complex, platinum-divinyltetrapropyldisiloxane complex, platinum-divinyltetrabutyldisiloxane complex, platinum -Divinyltetraphenyldisiloxane complex.
[0041]
Of the vinyl group-containing organosiloxanes, vinyl group-containing cyclic organosiloxanes are preferred. Examples of complexes of these with platinum include a platinum-vinylmethyl cyclic siloxane complex, a platinum-vinylethyl cyclic siloxane complex, and a platinum-vinylpropyl cyclic siloxane complex.
The vinyl group-containing organosiloxane may itself be used as a ligand for a metal, or may be used as a solvent for coordinating another ligand. A complex using a vinyl group-containing organosiloxane as a solvent and using the above-mentioned compound containing a carbonyl group as a ligand is particularly preferable as the catalyst [C] of the present invention.
[0042]
Specific examples of such a complex include a platinum-carbonyl complex vinylmethyl cyclic siloxane solution, a platinum-carbonyl complex vinylethyl cyclic siloxane solution, a platinum-carbonyl complex vinylpropyl cyclic siloxane solution, and a platinum-carbonyl complex divinyl. Tetramethyldisiloxane solution, platinum-carbonyl complex divinyltetraethyldisiloxane solution, platinum-carbonyl complex divinyltetrapropyldisiloxane solution, platinum-carbonyl complex divinyltetrabutyldisiloxane solution, platinum-carbonyl complex divinyltetraphenyldisiloxane solution A siloxane solution.
[0043]
The catalyst comprising these complexes may further contain components other than the compound containing a vinyl group and / or a carbonyl group. For example, a solvent other than a compound containing a vinyl group and / or a carbonyl group may be contained. Examples of these solvents include various alcohols and xylene, but are not limited thereto.
[0044]
As the alcohol, specifically, methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol, butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, n-amyl alcohol, isoamyl alcohol, hexyl alcohol, heptyl alcohol, octyl alcohol Aliphatic saturated alcohols such as, caprylic alcohol, nonyl alcohol, decyl alcohol, undecyl alcohol, lauryl alcohol, tridecyl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, eicosyl alcohol;
Aliphatic unsaturated alcohols such as allyl alcohol and crotyl alcohol;
Alicyclic alcohols such as cyclopentanol and cyclohexanol;
Aromatic alcohols such as benzyl alcohol and cinnamyl alcohol;
And heterocyclic alcohols such as furfuryl alcohol.
[0045]
An example using an alcohol as a solvent is a platinum-octal / octanol complex. By including these solvents, advantages such as easy handling of the catalyst and mixing with the polymer composition are obtained.
[0046]
Among the various catalysts listed above, a platinum-carbonyl complex vinylmethyl cyclic siloxane solution (particularly a complex represented by the following chemical formula 1) and a platinum-vinylmethyl cyclic siloxane complex (particularly a complex represented by a chemical formula 2 are preferred) ), A platinum-divinyltetramethyldisiloxane complex (preferably a complex represented by Chemical Formula 3), a platinum-octanal / octanol complex and the like are practically preferable, and among them, a platinum-carbonylvinylmethyl cyclic siloxane complex is particularly preferable.
[0047]
Here, when an organosiloxane such as a vinyl group-containing organosiloxane or a carbonyl group-containing organosiloxane is used as the compound forming the complex, the amount thereof is not particularly limited, but is 0.1 to 100 mol per 1 mol of the catalyst. Preferably, there is. The upper limit is more preferably not more than 20 mol%, more preferably not more than 6 mol% based on 1 mol of the catalyst. Specifically, a preferred ratio is 0.1 to 20 mol, more preferably 0.1 to 6 mol, per 1 mol of the catalyst. Within this range, the electrode is particularly excellent in stain resistance.
[0048]
When other carbonyl compounds such as aldehydes and ketones are used, the amount is preferably in the range of 0.1 to 1000 mol, more preferably in the range of 0.1 to 100 mol, per 1 mol of the catalyst.
[0049]
As a compound forming such a complex, a compound having a boiling point of 100 ° C. or higher, preferably 120 ° C. or higher, more preferably 150 ° C. or higher, further preferably 170 ° C. or higher is also a preferable embodiment. Within this range, the electrode is particularly excellent in stain resistance.
[0050]
Chemical formula 1: Pt⁰・ CO ・ (CH₂= CH (Me) SiO)₄
Chemical formula 2: Pt⁰・ (CH₂= CH (Me) SiO)₄
Chemical formula 3: Pt⁰−1.5 [(CH₂= CH (Me)₂Si)₂O]
The ratio of the Group 8 element metal (preferably platinum) contained in these catalysts is usually 0.1 to 10% by weight, preferably 1 to 5% by weight, more preferably 2 to 4% by weight, and particularly preferably. Is 2.5 to 3.5% by weight.
[0051]
The catalyst [C] is usually 0.1 to 100,000 ppm by weight, preferably 0.1 to 100,000 ppm by weight based on the organic polymer [A] containing a vinyl group (excluding the ethylene / α-olefin / non-conjugated diene copolymer). Is used in a proportion of 0.1 to 10,000 wt ppm, more preferably 1 to 5,000 wt ppm, and particularly preferably 5 to 1,000 wt ppm.
[0052]
When the catalyst [C] is used in a proportion within the above range, a polymer composition which can form a crosslinked rubber molded article having an appropriate crosslinking density and excellent strength and elongation properties is obtained. Use of the catalyst [C] in a proportion exceeding 100,000 ppm by weight is disadvantageous in terms of cost.
In the present invention, an uncrosslinked rubber molded article of the polymer composition not containing the catalyst [C] may be irradiated with light, γ-ray, electron beam or the like to obtain a crosslinked rubber molded article.
[0053]
[Reaction inhibitor [D]]
Examples of the reaction inhibitor [D] used as an optional component together with the catalyst [C] in the present invention include benzotriazole, an ethynyl group-containing alcohol (eg, ethynylcyclohexanol), acrylonitrile, an amide compound (eg, N, N-diallylacetamide, N, N-diallylbenzamide, N, N, N ′, N′-tetraallyl-o-phthalic diamide, N, N, N ′, N′-tetraallyl-m-phthalic diamide, N, N, N ′, Organic peroxides such as N'-tetraallyl-p-phthalic acid diamide), sulfur, phosphorus, nitrogen, amine compounds, sulfur compounds, phosphorus compounds, tin, tin compounds, and hydroperoxides are preferred.
[0054]
Among them, a reaction inhibitor having no siloxane bond is preferable. Here, the siloxane bond means a (Si-O-) bond.
[0055]
Further, among these, a reaction inhibitor having a structure composed of a carbon atom, a hydrogen atom, and an oxygen atom is preferable. In one embodiment, it is particularly preferable to consist only of carbon atoms, hydrogen atoms and oxygen atoms. Within this range, the electrode is particularly excellent in stain resistance.
[0056]
In addition, the reaction inhibitor has the above-mentioned properties or has a boiling point of 100 ° C. or more, preferably 120 ° C. or more, more preferably 150 ° C. or more, and particularly preferably, irrespective of the above-mentioned properties. Compounds having a temperature of 170 ° C. or higher can be preferably mentioned. There is no particular upper limit. Such a compound is particularly excellent in the stain resistance of the electrode.
[0057]
The reaction inhibitor [D] is used in an amount of 0 to 50 parts by weight, usually 0.0001 to 50 parts by weight, preferably 0.0001 to 30 parts by weight, based on 100 parts by weight of the organic polymer [A] having a vinyl group. , More preferably 0.0001 to 20 parts by weight, further preferably 0.0001 to 10 parts by weight, particularly preferably 0.0001 to 5 parts by weight.
[0058]
When the reaction inhibitor [D] is used in a proportion of 50 parts by weight or less, a polymer composition having a high crosslinking speed and excellent productivity of a crosslinked rubber molded article can be obtained. It is not preferable to use the reaction inhibitor [D] in a proportion exceeding 50 parts by weight because it is disadvantageous in terms of cost.
[0059]
It is preferable that the polymer composition of the present invention is crosslinked after flowing to every corner of the electrode when performing insert molding with the electrode. By adding an inhibitor, it is possible to prevent cross-linking before the material flows to every corner of the electrode. Can be suppressed, the adhesive strength to the electrode is excellent, and the sealing performance is further improved. Therefore, it is particularly suitable for a fuel cell seal.
[0060]
[Other ingredients]
The polymer composition for a fuel cell seal component according to the present invention can exhibit its characteristics most when used as a crosslinked product such as a crosslinked polymer molded product or a crosslinked polymer foam molded product.
[0061]
In the polymer composition for a fuel cell seal part according to the present invention, a conventionally known rubber reinforcing agent, an inorganic filler, an antioxidant, a processing aid, a vulcanization accelerator, depending on the intended use of the crosslinked product and the like. Additives such as an organic peroxide, a crosslinking assistant, a foaming agent, a foaming assistant, a coloring agent, a dispersant, and a flame retardant can be blended within a range that does not impair the object of the present invention.
[0062]
The rubber reinforcing agent has an effect of improving mechanical properties such as tensile strength, tear strength, and abrasion resistance of the crosslinked (vulcanized) rubber. Specific examples of such a rubber reinforcing agent include carbon blacks such as SRF, GPF, FEF, HAF, ISAF, SAF, FT, MT, etc .; Black, finely divided silica, silica, and the like.
[0063]
Specific examples of silica include fumed silica and precipitated silica. These silicas may be surface-treated with a reactive silane such as hexamethyldisilazane, chlorosilane, alkoxysilane, or a low-molecular-weight siloxane. The specific surface area (BET method) of these silicas is preferably 10 m2 / g or more, and more preferably 30 to 500 m2 / g.
[0064]
The type and amount of these rubber reinforcing agents can be appropriately selected depending on the application, but the amount of the rubber reinforcing agent is usually selected from an organic polymer containing a vinyl group (however, ethylene / α-olefin / non-conjugated diene copolymer). It is at most 300 parts by weight, preferably at most 200 parts by weight, per 100 parts by weight of [A].
[0065]
Specific examples of the inorganic filler include light calcium carbonate, heavy calcium carbonate, talc, clay and the like.
[0066]
The type and amount of these inorganic fillers can be appropriately selected depending on the application, but the amount of the inorganic filler is usually an organic polymer (excluding ethylene / α-olefin / non-conjugated diene copolymer) [ A] Up to 300 parts by weight, preferably up to 200 parts by weight, per 100 parts by weight.
[0067]
Further, in the polymer composition for a fuel cell seal part of the present invention, the plasticizer does not contain, or the content of the plasticizer is an organic polymer (excluding ethylene / α-olefin / non-conjugated diene copolymer). ) [A]) It is desirable that the amount be 20 parts by weight or less based on 100 parts by weight.
When the plasticizer is added, the preferred range is 15 parts by weight or less, more preferably 10 parts by weight, based on 100 parts by weight of the organic polymer (however, excluding the ethylene / α-olefin / non-conjugated diene copolymer) [A]. Parts by weight, more preferably 5 parts by weight or less, further preferably 3 parts by weight or less, particularly preferably 1 part by weight or less, particularly preferably 0.1 part by weight or less, particularly preferably 0.01 part by weight or less. In this range, the extraction resistance is good, so that there is no contamination with the fuel gas, and a fuel cell with high fuel efficiency can be provided. In the present invention, it is preferable that substantially no plasticizer is contained. This means that the plasticizer has not been added, or even when it has been added, the amount is 0.01% by weight or less.
As the plasticizer, a plasticizer that is usually used for rubber can be used.
[0068]
Specifically, petroleum plasticizers such as process oil, lubricating oil, paraffin, liquid paraffin, petroleum asphalt, petrolatum, etc .;
Coal tar plasticizers such as coal tar and coal tar pitch;
Fatty oil-based plasticizers such as castor oil, linseed oil, rapeseed oil, and coconut oil;
Tall oil;
sub;
Waxes such as beeswax, carnauba wax and lanolin;
Fatty acids and fatty acid salts such as ricinoleic acid, palmitic acid, barium stearate, calcium stearate, zinc laurate;
Synthetic polymer substances such as petroleum resin, atactic polypropylene, and coumarone indene resin can be given. Among them, a petroleum plasticizer is preferably used, and particularly, a process oil is preferably used.
[0069]
Examples of the anti-aging agent include amine-based, hindered phenol-based, or sulfur-based anti-aging agents, and as described above, these anti-aging agents are used within a range that does not impair the object of the present invention. Can be
Examples of the amine anti-aging agent used in the present invention include diphenylamines, phenylenediamines and the like.
[0070]
Specific examples of the diphenylamines include p- (p- toluenesulfonylamide)-diphenylamine, 4,4'- (α, α-dimethylbenzyl) diphenylamine, 4,4'- dioctyl diphenylamine, diphenylamine and acetone High-temperature reaction product of diphenylamine with acetone, low-temperature reaction product of diphenylamine with aniline and acetone, reaction product of diphenylamine with diisobutylene, octylated diphenylamine, dioctylated diphenylamine, p, p ′ -Dioctyl diphenylamine, alkylated diphenylamine and the like.
[0071]
Specific examples of phenylenediamines include N, N '-{diphenyl-p-phenylenediamine, n- {isopropyl-N'-phenyl-p-phenylenediamine, and N, N'-{di-2-} naphthyl-p-. Phenylenediamine, N-cyclohexyl-N'-phenyl-p-phenylenediamine, N-phenyl-N '-(3-methacryloyloxy-2- {hydroxypropyl) -p-phenylenediamine, N, N'-} bis (1- Methylheptyl) -p-phenylenediamine, N, N ′-{bis (1,4-dimethylpentyl) -p-phenylenediamine, N, N ′-} bis (1-ethyl-3- {methylpentyl) -p-phenylenediamine , N- (1,3-dimethylbutyl) -N'-phenyl-p-phenylenediamine, phenylhexyl p- phenylenediamine, and the like p- phenylenediamines, such as phenyl dioctyl -p- phenylenediamine.
[0072]
Among these, 4,4 '-([alpha], [alpha] -dimethylbenzyl) diphenylamine and N, N'-{di-2-} naphthyl-p-phenylenediamine are particularly preferred.
These compounds can be used alone or in combination of two or more.
[0073]
As the hindered phenolic antioxidant used in the present invention, specifically,
(1) 1,1,3-tris- (2-methyl-4-hydroxy-5-t-butylphenyl) butane,
(2) 4,4 '-{butylidenebis- (3-methyl-6-t-butylphenol);
(3) 2,2-thiobis (4-methyl-6-t-butylphenol),
(4) 7-octadecyl-3- (4'-hydroxy-3 ', 5'-di-t-butylphenyl) propionate,
(5) tetrakis- [methylene-3- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate methane;
(6) pentaerythritol- {tetrakis [3- (3,5-di-t-} butyl-4-hydroxyphenyl) propionate],
(7) triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate],
(8) 1,6-hexanediol-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate],
(9) 2,4-bis (n-octylthio) -6- (4-hydroxy-3,5- {di-t- {butylanilino) -1,3,5-} triazine,
(10) Tris- (3,5-di-t-butyl-4-hydroxybenzyl) -isocyanurate,
(11) 2,2-thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate],
(12) N, N '-{hexamethylenebis (3,5-di-t-butyl-4-hydroxy) -hydrocinnamide;
(13) 2,4-bis [(octylthio) methyl] -o-cresol,
(14) 3,5-di-t-butyl-4-hydroxybenzyl-phosphonate-diethyl ester,
(15) tetrakis [methylene (3,5-di-t- {butyl-4-} hydroxyhydrocinnamate)] methane,
(16) octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate,
(17) 3,9-bis [2- {3- (3-t-butyl-4- {hydroxy-5- {methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4-8,10- Tetraoxaspiro [5,5] undecane
And the like. Among them, the phenol compounds (5) and (17) are particularly preferred.
[0074]
As the sulfur-based antioxidant used in the present invention, a sulfur-based antioxidant commonly used for rubber is used.
Specifically, imidazole aging such as 2-mercaptobenzimidazole, zinc salt of 2-mercaptobenzimidazole, 2-mercaptomethylbenzimidazole, zinc salt of 2-mercaptomethylbenzimidazole, and zinc salt of 2-mercaptomethylimidazole Inhibitor;
Aliphatic thioether aging such as dimyristyl thiodipropionate, dilauryl thiodipropionate, distearyl thiodipropionate, ditridecyl thiodipropionate, pentaerythritol-tetrakis- (β-lauryl-thiopropionate) And an inhibitor. Among these, in particular, 2-mercaptobenzimidazole, zinc salt of 2-mercaptobenzimidazole, 2-mercaptomethylbenzimidazole, zinc salt of 2-mercaptomethylbenzimidazole, pentaerythritol- {tetrakis- (β- {lauryl-} thiopropio) Is preferred.
[0075]
As the above-mentioned processing aid, a compound used for normal processing of rubber can be used. Specifically, higher fatty acids such as ricinoleic acid, stearic acid, palmitic acid and lauric acid; salts of higher fatty acids such as barium stearate, zinc stearate and calcium stearate; ricinoleic acid, stearic acid, palmitic acid and lauric acid And higher fatty acid esters.
[0076]
Such a processing aid is usually 10 parts by weight or less based on 100 parts by weight of an organic polymer containing a vinyl group (however, excluding an ethylene / α-olefin / non-conjugated diene copolymer) [A]. It is preferably used in a proportion of 5 parts by weight or less, but it is desirable to appropriately determine an optimum amount according to required physical properties.
In the present invention, both the addition crosslinking and the radical crosslinking may be performed by using an organic peroxide in addition to the above-mentioned catalyst [C]. The organic peroxide is an organic polymer having a vinyl group (excluding an ethylene / α-olefin / non-conjugated diene copolymer) [A] A proportion of about 0.1 to 10 parts by weight with respect to 100 parts by weight. Used in As the organic peroxide, a conventionally known organic peroxide that is usually used at the time of rubber crosslinking can be used.
[0077]
When an organic peroxide is used, it is preferable to use a crosslinking assistant together.
Specific examples of the crosslinking assistant include sulfur; quinone dioxime compounds such as p-diquinone dioxime; methacrylate compounds such as polyethylene glycol dimethacrylate; allyl compounds such as diallyl phthalate and triallyl cyanurate; System compound; divinylbenzene and the like. Such a crosslinking aid is used in an amount of 0.5 to 2 mol, preferably about equimolar, based on 1 mol of the organic peroxide used.
[0078]
In the crosslinkable polymer composition according to the present invention, it can be used by blending with other known rubbers as long as the object of the present invention is not impaired.
Examples of such other rubbers include ethylene / α-olefin / non-conjugated polyene copolymer, natural rubber (NR), isoprene-based rubber such as isoprene rubber (IR), butadiene rubber (BR), styrene-butadiene rubber ( SBR), acrylonitrile-butadiene rubber (NBR), and conjugated diene rubbers such as chloroprene rubber (CR).
[0079]
[Preparation of polymer composition and fuel cell seal parts]
As described above, the polymer composition for a fuel cell seal component according to the present invention can exhibit its characteristics most when used as a crosslinked molded article. Therefore, the fuel cell sealing component according to the present invention, for example, the fuel cell sealing component, is usually a cross-linked molded article.
[0080]
In order to produce a crosslinked molded article from the polymer composition for a fuel cell seal component according to the present invention, an uncrosslinked compound, for example, a compounded rubber is once added in the same manner as when vulcanizing (crosslinking) a general rubber. It may be prepared and then crosslinked after shaping the blend into the desired shape.
The fuel cell sealing component of the present invention is preferably, for example, a solid polymer type (solid polymer electrolyte type) fuel cell sealing component.
[0081]
As a crosslinking method, any of a method of heating using a crosslinking agent (SiH group-containing compound [B]) or a method of irradiation with light, γ-ray, or electron beam may be adopted.
[0082]
First, the polymer composition for a fuel cell seal component according to the present invention is prepared, for example, by the following method.
That is, the polymer composition for a fuel cell seal component according to the present invention is prepared by using an internal mixer (closed mixer) such as a planetary mixer, a Banbury mixer, a kneader, or an intermix to form an organic compound containing a vinyl group. Polymer (excluding ethylene / α-olefin / non-conjugated diene copolymer) [A], additives such as a rubber reinforcing agent, an inorganic filler, and a softener are preferably added at a temperature of 50 to 180 ° C. for 3 to 10 After kneading for 3 minutes, a SiH group-containing compound [B] and, if necessary, a catalyst [C], a reaction inhibitor [D], It can be prepared by additionally mixing a vulcanization accelerator and a crosslinking aid and kneading the mixture at a roll temperature of 100 ° C. or lower for 1 to 30 minutes.
[0083]
When the kneading temperature in the internal mixer is low, an organic polymer containing a vinyl group (excluding an ethylene / α-olefin / non-conjugated diene copolymer) [A], a compound containing a SiH group [B], an antioxidant, a colorant, a dispersant, a flame retardant, and the like may be simultaneously kneaded together with a rubber reinforcing agent, an inorganic filler, a softener, and the like.
The polymer composition for a fuel cell seal component according to the present invention prepared as described above includes a LIM molding machine, an injection molding machine, a transfer molding machine, a press molding machine, an extrusion molding machine, a calender roll, and the like. According to the various molding methods used, it can be molded into an intended shape, and can be crosslinked simultaneously with molding or by introducing the molded product into a vulcanization tank. Among these, the LIM molding machine is suitable for producing a desired fuel cell seal part from the viewpoint of insert molding with carbon or a film, blanket molding, thickness precision, and high speed molding. Further, injection molding and compression molding are also suitable. The cross-linking conditions are as follows: heating at a temperature of 50 to 270 ° C. for 0.5 to 30 minutes, or irradiation of light, γ-ray, or electron beam by the above-described method to form a cross-linked rubber molded product, ie, a fuel in the present invention. A battery seal part is obtained. In addition, crosslinking can be performed at room temperature.
[0084]
In this crosslinking step, a mold may be used, or the crosslinking may be performed without using a mold. When a mold is not used, the steps of molding and crosslinking are usually carried out continuously. As a heating method in the vulcanizing tank, a heating tank such as hot air, a fluidized bed of glass beads, UHF (ultra-high frequency electromagnetic wave), and steam can be used.
When the polymer composition according to the present invention is particularly applied to LIM molding, it is desirable to prepare a liquid polymer composition in which the SiH group-containing compound [B] and the catalyst [C] are separately compounded.
[0085]
That is, depending on the viscosity of the material, the organic polymer containing vinyl groups (however, ethylene) can be used by an internal mixer (closed mixer) such as a Banbury mixer, a kneader or an intermix or a stirrer such as a planetary mixer.・ Excluding α-olefin / non-conjugated diene copolymer) [A], additives such as a rubber reinforcing agent, an inorganic filler, a softening agent and a SiH group-containing compound [B] are kneaded for 3 to 10 minutes. A coalescing composition (1) is prepared. Further, an organic polymer containing a vinyl group (excluding an ethylene / α-olefin / non-conjugated diene copolymer) [A], an additive such as a rubber reinforcing agent, an inorganic filler, a softener and a catalyst [C] If necessary, the reaction inhibitor [D] is kneaded for 3 to 10 minutes to prepare a liquid polymer composition (2). Subsequently, the liquid polymer composition (1) and the liquid polymer composition (2) are placed in a dedicated pail can or a directly connectable cartridge that can be directly connected to the LIM molding apparatus, and are measured and mixed through a mixing apparatus. By performing LIM molding, a desired fuel cell seal component can be obtained.
[0086]
Therefore, an organic polymer containing a vinyl group (excluding an ethylene / α-olefin / non-conjugated diene copolymer) [A], a compound containing a SiH group [B], and, if necessary, a rubber reinforcing agent and an inorganic filler And a polymer composition (1) comprising an additive such as a softener and an organic polymer having a vinyl group (excluding an ethylene / α-olefin / non-conjugated diene copolymer) [A], and A liquid polymer composition (2) comprising a catalyst [C], a reaction inhibitor [D] as needed, and optionally additives such as a rubber reinforcing agent, an inorganic filler, and a softener is mixed. LIM molding is a preferred embodiment of the method for producing a fuel cell seal component of the present invention.
[0087]
Accordingly, an organic polymer containing a vinyl group (excluding an ethylene / α-olefin / non-conjugated diene copolymer) [A], a compound containing a SiH group [B], and a rubber reinforcing agent and an inorganic filler as required , A polymer composition (1) comprising an additive such as a softener, or an organic polymer containing a vinyl group (excluding ethylene / α-olefin / non-conjugated diene copolymer) [A], and a catalyst A polymer composition (2) comprising [C], a reaction inhibitor [D] if necessary, and further additives such as a rubber reinforcing agent, an inorganic filler and a softening agent, if necessary; further, a polymer composition The material comprising the product (1) and the polymer composition (2) is suitable as a material for a sealing part for a fuel cell, particularly a material used for LIM molding.
[0088]
【The invention's effect】
The polymer composition for a fuel cell seal component according to the present invention has a high crosslinking rate, excellent productivity (high-speed moldability), compression set resistance, gas barrier properties (hydrogen, oxygen, water vapor, etc.) from 80 ° C. A fuel cell seal part with excellent properties such as low permeability in an environment of about 120 ° C), heat resistance, acid resistance (resistance to sulfonic acid such as sulfuric acid), and cooling water resistance (LLC etc.) Can be provided.
[0089]
Since the fuel cell seal component according to the present invention is prepared from the above polymer composition, it is excellent in productivity and excellent in properties such as compression set resistance, gas barrier property, acid resistance, and cooling water resistance.
ADVANTAGE OF THE INVENTION According to the manufacturing method of the fuel cell seal component concerning this invention, a fuel cell seal component excellent in characteristics, such as compression set distortion resistance, gas barrier property, heat resistance, acid resistance, and cooling water resistance, can be produced at high speed.
[0090]
【Example】
Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to these examples.
The composition, iodine value, intrinsic viscosity [η], etc. of the copolymer [A] used in Examples and Comparative Examples were determined by measurement or calculation by the following methods.
(1) Composition of copolymer [A]
The composition of the copolymer [A] is^ThirteenIt was measured by the C-NMR method.
(2) Iodine value of copolymer [A]
The iodine value of the copolymer [A] was determined by a titration method.
(3) Number average molecular weight
The number average molecular weight of the organic polymer [A] containing a vinyl group was measured using GPC.
For GPC, GMH-HT and GMH-HTL manufactured by Tosoh Corporation were used for the column, and orthodichlorobenzene was used for the solvent. )
[0091]
[Example 1]
100 parts by weight of polyisobutylene (A-1) having a vinyl group (manufactured by Kaneka Chemical Co., Ltd., trade name: Epion 600A, molecular weight = 20,000) and 30 parts by weight of silica [trade name: Nipsil VN3, manufactured by Nippon Silica Industry Co., Ltd.] The mixture was kneaded with a planetary mixer having a capacity of 2 liters (trade name: PLM-2, manufactured by Inoue Seisakusho) to obtain a compound (I-1).
[0092]
Next, 130 parts by weight of this compound (I-1) was mixed with a SiH group-containing compound represented by C6H5-Si (OSi (CH3) 2H) 3 (trade name X-93-916, manufactured by Shin-Etsu Chemical Co., Ltd.) [B 4 parts by weight (crosslinking agent), 0.1 part by weight of 1-ethynyl-1-cyclohexanol as a reaction inhibitor [D] (Nissin Chemical Co., Ltd.), and isopropyl chloroplatinic acid concentration of 2% by weight as a catalyst [C]. 0.1 part by weight of an alcohol solution (brand name PL-2 manufactured by Shin-Etsu Chemical Co., Ltd.) is added, and the mixture is kneaded three times with a three-inch φ three roll [Kodaira Mfg. Co., Ltd., three roll mill]. After that, pressure was applied at 120 ° C. for 6 minutes using a 50-ton press molding machine to prepare a crosslinked rubber sheet having a thickness of 2 mm.
[0093]
Using the sheet obtained as described above, a physical property test was performed according to the following methods (4) to (8).
(4) Tensile test
According to JIS {K6251, a tensile test was performed at a measurement temperature of 23 ° C. and a tensile speed of 500 mm / min, and the tensile strength TB at break and the elongation EB of the crosslinked sheet were measured.
(5) Gas barrier properties
In accordance with JIS K 7126, a gas barrier test was performed under the following conditions to measure an oxygen permeability coefficient.
(Measurement condition)
Oxygen 100%, test temperature 23 ° C, humidity 0%.
(testing machine)
Differential pressure gas permeation tester manufactured by Toyo Seiki Co., Ltd.
(6) Acid resistance
After performing an immersion test in an acidic solution under the following conditions in accordance with JIS K 6258 (1993), tensile elongation, strength, and volume change rate were measured, and each change rate (hardness was a change value) was determined.
(Immersion conditions)
25 ° C, 168 hours.
(Acid solution)
A 35% by weight solution of hydrochloric acid and a 70% by weight solution of sulfuric acid were used.
[0094]
(7) Extractability
After performing an immersion test in an n-hexane solution under the following conditions in accordance with JIS K 6258 (1993), the volume change rate was measured, and each change rate (hardness was a change value) was determined.
(Immersion conditions)
25 ° C, 168 hours.
If the extract is small, it hardly mixes into the reaction gas of the fuel cell, and there is little possibility that the fuel efficiency is reduced.
(8) Electrode contamination
The crosslinked rubber was brought into contact with the carbon electrode according to JIS K6267 (1996), and the contamination was visually evaluated.
(Contamination conditions)
100 ° C x 168 hours
○: no contaminants adhere to the electrode
Δ: Contaminants adhere to the electrode.
×: A large amount of contaminants adhere to the electrode.
As long as no contaminants adhere to the electrodes, there is little occurrence of contact failure, and the function as a fuel cell can be sufficiently performed.
[Example 2]
In Example 1, in place of 30 parts by weight of silica used in Example 1, 30 parts by weight of carbon black [trade name: Seast G-116, manufactured by Tokai Carbon Co., Ltd.] was used as shown in Table 1. Except for the above, a crosslinked rubber sheet was obtained in the same manner as in Example 1.
The obtained crosslinked rubber sheet was subjected to a tensile test, a gas barrier test, and an acid resistance test. Table 2 shows the results.
[0095]
[Example 3]
In Example 2, as shown in Table 1, in place of the vinyl group-containing polyisobutylene (A-1) used in Example 2, an organic polymer polyisobutylene containing a vinyl group [Kanebuchi Chemical Co., Ltd. A cross-linked rubber sheet was obtained in the same manner as in Example 2, except that (A-2) was used, and the product name was {Epion 400A} number average molecular weight = 10000}.
[0096]
The obtained crosslinked rubber sheet was subjected to a tensile test, a gas barrier test, and an acid resistance test. Table 2 shows the results.
[0097]
[Example 4]
In Example 2, as shown in Table 1, instead of the vinyl group-containing polyisobutylene (A-1) used in Example 2, a vinyl group-containing polyisobutylene [manufactured by Kaneka Chemical Co., Ltd., A crosslinked rubber sheet was obtained in the same manner as in Example 2, except that the trade name {Epion 200A} number average molecular weight = 5000] (A-3) was used. The obtained crosslinked rubber sheet was subjected to a tensile test, a gas barrier test, and an acid resistance test. Table 2 shows the results.
[0098]
[Example 5]
In Example 2, as shown in Table 1, in place of the vinyl group-containing polyisobutylene (A-1) used in Example 2, a vinyl group-containing polypropylene glycol [Kanebuchi Chemical Co., Ltd.] A crosslinked rubber sheet was obtained in the same manner as in Example 2 except that the product name “MS Polymer-203A} number average molecular weight = 8000] ((A-4)) was used. A test, a gas barrier test, and an acid resistance test were performed, and the results are shown in Table 2.
[0099]
[Example 6]
In Example 2, as shown in Table 1, in place of the vinyl group-containing polyisobutylene (A-1) used in Example 2, a vinyl group-containing polypropylene glycol [Kanebuchi Chemical Co., Ltd.] A crosslinked rubber sheet was obtained in the same manner as in Example 2 except that the product name (MS Polymer-203A) number average molecular weight = 9000] ((A-5)) was used.
The obtained crosslinked rubber sheet was subjected to a tensile test, a gas barrier test, and an acid resistance test. Table 2 shows the results.
[0100]
[Example 7]
In Example 3, as shown in Table 1, except that 1-ethynyl-1-cyclohexanol (E) used in Example 3 was replaced with divinyldisiloxane (E). In the same manner as in the above, a crosslinked rubber sheet was obtained. The obtained crosslinked rubber sheet was subjected to a tensile test, a gas barrier test, and an acid resistance test. Table 2 shows the results.
[0101]
[Comparative Example 1]
In Example 2, as shown in Table 1, except that EPDM (A-3) containing an ethylidene group was used instead of polyisobutylene (A-1) containing a vinyl group used in Example 2. An attempt was made to obtain a crosslinked rubber sheet in the same manner as in Example 2, but the crosslinking reaction was extremely slow, and a crosslinked rubber sheet could not be obtained.
[0102]
Example 8
As shown in Table 1, a crosslinked rubber sheet was obtained in the same manner as in Example 3 except that 23 parts by weight of a plasticizer (manufactured by Idemitsu Chemical Co., PAO5004) was added. The obtained crosslinked rubber sheet was subjected to a tensile test, a gas barrier test, and an acid resistance test. Table 2 shows the results.
[0103]
The obtained crosslinked rubber sheet was subjected to a tensile test, a gas barrier test, an acid resistance test, extractability, and electrode contamination. Table 2 shows the results.
[0104]
[Table 1]

[0105]
[Table 2]

Claims (11)

A fuel cell seal component comprising: a vinyl group-containing organic polymer [A] (excluding an ethylene / α-olefin / non-conjugated polyene copolymer); and a SiH group-containing compound [B]. Polymer composition. The SiH group-containing compound [B] is used in an amount of 0.1 to 100 parts by weight based on 100 parts by weight of the vinyl group-containing organic polymer [A] (excluding the ethylene / α-olefin / non-conjugated polyene copolymer). The polymer composition for a fuel cell seal part according to claim 1, wherein the polymer composition is contained in an amount of 1 part by weight. The SiH group-containing compound [B] is bonded to a silicon atom per vinyl group contained in the vinyl group-containing organic polymer [A] (excluding the ethylene / α-olefin / non-conjugated polyene copolymer). The polymer composition for a fuel cell seal part according to claim 1, wherein the polymer composition contains 0.2 to 10 hydrogen atoms. The polymer composition comprises a vinyl group-containing organic polymer [A] (excluding an ethylene / α-olefin / non-conjugated polyene copolymer) and a SiH group-containing compound [B], and a catalyst [C]. The polymer composition for a fuel cell seal part according to any one of claims 1 to 3, which comprises: The polymer composition for a fuel cell seal part according to any one of claims 1 to 4, wherein the polymer composition further comprises a reaction inhibitor [D]. The polymer composition contains no plasticizer or contains a vinyl group-containing organic polymer [A] (excluding an ethylene / α-olefin / non-conjugated polyene copolymer). The polymer composition for a fuel cell seal part according to any one of claims 1 to 5, wherein the amount is 20 parts by weight or less based on part by weight. The number average molecular weight of the vinyl group-containing organic polymer (excluding ethylene / α-olefin / non-conjugated polyene copolymer) [A] is in the range of 500 to 100,000. 7. The polymer composition for a fuel cell seal part according to any one of claims 6 to 6. A fuel cell seal part obtained by molding the polymer composition according to claim 1. 9. The fuel cell sealing part according to claim 8, which is obtained by LIM molding, injection molding or compression molding. A method for producing a fuel cell seal part, comprising crosslinking the polymer composition for a fuel cell seal according to any one of claims 1 to 7. A fuel cell comprising the fuel cell seal component according to claim 8.