半結晶ポリオレフィン材料の合成:精密メチル分岐によるステレオレテントチェーンウォーキング
David N Vaccarello1, Kyle S O'Connor1, Pasquale Iacono1
1Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853-1301 , United States.
Journal of the American Chemical Society
|April 24, 2018
まとめ
新しいC2対称ニッケル触媒は,1-ブテンの地域および同選択的ポリメリゼーションを可能にします. これは,チェーンウォーキングを通じて高いステレオ化学保存を持つ新しい半結晶ポリオレフィンを生成します.
科学分野:
- ポリマー化学
- オルガノメタリック触媒
- 材料科学
背景:
- ポリオレフィンは重要な産業用材料です
- オレフィンのステレオ制御ポリメリゼーションは依然として課題です.
- チェーンウォーキングポリメリゼーションはユニークなポリマー構造を提供します.
研究 の 目的:
- ステレオ選択的1-ブテンポリメリゼーションのための新しい触媒を開発する.
- イソタクティック 4,2-ポリ,1-ブーテンの製造を調査する.
- オレフィンポリメリゼーションにおけるチェーンウォーキングメカニズムを探求する.
主な方法:
- C2対称ニッケル触媒の合成
- 1-ブテンの地域および同選択的ポリメリゼーション.
- ポリマーの微細構造と熱的性質の特徴
主要な成果:
- 1-ブテンのポリメリゼーションのためのC2対称ニッケル触媒の発見.
- 新しい半結晶型ポリオレフィンであるイソタキス型4,2-ポリー ((1-ブテン) の製造.
- 高いエナチオ表面選択性 (84%まで) と融解温度 (86°Cまで) を達成した.
結論:
- この触媒システムは,チェーンウォーキングポリメリゼーションの精密なステレオ化学制御を可能にします.
- 新しい半結晶型ポリオレフィンが合成され,応用が可能となった.
- ステレオセレクティブオレフィンポリメリゼーションの 重要な進歩です
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