ランダムな触媒が,クマダの触媒-移転ポリコンデンサーションのポリメリ化されたポリ ((3-ヘキシルチオフェン) 鎖に沿って歩いている
Roman Tkachov1, Volodymyr Senkovskyy, Hartmut Komber
1Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany.
Journal of the American Chemical Society
|May 15, 2010
まとめ
ニッケル触媒は,クマダ触媒-移転ポリコンデンサーションの過程で,聚合するポリ ((3-ヘキシルチオフェン) 鎖に沿って"歩く"ことができます. この予期せぬ移動性は,内部フェニル環を持つユニークなポリマー構造につながり,チェーンウォーキングメカニズムを示唆します.
科学分野:
- ポリマー化学のポリマー化学について
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
背景:
- クマダの触媒移転ポリコンデンセーションは,ポリ・3・ヘキシルチオフェン (P3HT) のような結合ポリマーを合成するための重要な方法である.
- 触媒の行動,特にニッケル (Ni) 触媒の移動性を理解することは,ポリマーの構造と性質を制御するために不可欠です.
研究 の 目的:
- 事件を調査するために,
- 歩いて歩いて歩いて歩いて歩いて
- P3HTのポリメリゼーション中のNi触媒の振る舞い.
- 触媒移転のメカニズムとそのポリマー末端群形成への影響を解明する.
主な方法:
- エンドグループ分析を簡素化するために,新しいイニシアター,Br-C(6) H(4) -Ni(dppe) -Brの合成.
- 新型イニシアターを使用したP3HTのKumada触媒-転送ポリコンデンサ.
- 末端群と構造的異常を特定するために,ポリマー製品の分析.
- ランダムなジャンプモデルの数値分析.
主要な成果:
- 2つの異なるP3HT製品が形成されました: 1つは正常なパラブロモフェニル末端群で,もう1つはポリマー鎖内の内部フェニル環です.
- 内部フェニル環を持つP3HTの比率は,より高いポリメリゼーション度で増加した.
- 制御実験では,分子間触媒の移転が認められず,分子内触媒の移転が認められた.
結論:
- Ni触媒は,有意な分子内移動性を示し,
- 歩いて歩いて歩いて歩いて歩いて
- 成長するP3HT鎖に沿って反対の端まで.
- ランダムな触媒のジャンプとエンドグループの"粘着"の組み合わせが,ポリコンデンサーションプロセスを支配する.
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