オリゴーマー-オリゴーマー対オリゴーマー-モノマーC(2) -C(2) '結合反応は,ポリピロールの成長において発生する

J C Lacroix¹, F Maurel, P C Lacaze

¹Institut de Topologie et de Dynamique des Systèmes, Université de Paris 7-Denis Diderot, associé au CNRS (UPRES-A 7086), 1 rue Guy de la Brosse, 75005 Paris, France.

Journal of the American Chemical Society

|July 18, 2001

まとめ

オリゴピロールの電気化学的酸化がモデル化されました. より長いオリゴピロールの結合距離が短く,水中の二分化が速く,ポリマー形成メカニズムに影響することが観察されました.

科学分野:

電気化学電気化学について
コンピューティング・ケミストリー
ポリマーサイエンスの科学

背景:

オリゴピロールは,重要な伝導性ポリマーです.
根幹-カタン結合の理解は,ポリメリゼーションを制御する鍵です.

研究の目的:

オリゴピロール基-カチオンのC(2) -C(2) '結合反応をモデル化するために.
オリゴーマー長さと溶媒の作用が結合メカニズムに与える影響を調査する.

主な方法:

トランジション状態の計算が採用されました.
電気化学的酸化により,根幹カチオンが生成される.
溶媒効果はモデリングに組み込まれました.

主要な成果:

移行状態のカップリング距離は,オリゴーマー長さの増加とともに減少します.
ダイメリゼーション率はガス相では低下するが,水ではオリゴーマー長さに伴い増加する.
オリゴーマー-モノマー結合は,クアターピロールとセキシピロール形成のオリゴーマー-オリゴーマー結合よりも速い.

結論:

溶媒の極性性は,オリゴピロールのラジカルカチオン二酸化率に大きく影響する.
長いオリゴピロール形成のメカニズムには,ディケーション・ニュートラル・ユニット・カップリングが含まれる可能性があります.
発見は,ピロール誘導体の電ポリメリゼーションの制御に関する洞察を提供します.

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