モノ ((イミダゾリン-2-イミナト) タイタン複合体は,低量のメチルアルミノキサンでエチレンポリメリゼーション用です
Dana Shoken1, Manab Sharma, Mark Botoshansky
1Schulich Faculty of Chemistry, Institute of Catalysis Science and Technology, Technion - Israel Institute of Technology, Technion City, 32000 Haifa, Israel.
Journal of the American Chemical Society
|August 17, 2013
まとめ
研究者は,大量のイミダゾリン-2-イミナトリガンドを含むチタン複合体を用いてエチレンポリメリゼーションを調査した. 特定の複合体で,アルミニウムとチタンの比率は8.8で最適の触媒活性が達成されました.
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:
- タイタニウム複合体は,オレフィンポリメリゼーションにおける重要な触媒である.
- 大容量のリガンドは,触媒の活性とポリマーの特性に影響を与える可能性があります.
- 活性種を理解することは,ポリメリゼーションプロセスを最適化するための鍵です.
研究 の 目的:
- 大量のイミダゾリン-2-イミナトリガンドを含むチタン複合体を用いてエチレンポリメリゼーションを調査する.
- LTiCl3複合体とそのメチル化派生物を準備し,特徴づけること.
- 触媒活動のための最適な条件を決定し,コカタリストの比率に焦点を当てます.
主な方法:
- イミダゾリン-2-イミナトリガンドを含むチタン複合体の合成.
- メチルアルミノキサン (MAO) および/またはトリス (pentafluorophenyl) ボラン (TTPB) のコカタリシストを用いたエチレンポリメリゼーション実験.
- タイタン複合体の特徴とポリメリゼーション活動の分析.
主要な成果:
- タイタン複合体とMAO/TTPBコカタリストによるエチレンポリメリゼーションの探索.
- 活性種の研究のためにLTiCl3複合体とそのメチル化形態の調製.
- 特定の複合物との最大触媒活性のための最適なアルミニウム:チタン比率8を特定する.
結論:
- この研究は,チタン-イミダゾリン-2-イミナトシステムによるエチレンポリメリゼーションに関与する活性種についての洞察を提供します.
- 触媒の性能は,リガンド構造とコカタリスト比率に敏感です.
- 8のAl:Ti比を含む最適化された条件では,触媒活性が強化されます.
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