触媒性エチレンポリメリゼーションにおける極性コモノマー連鎖選択性の強化のためのバイメタリック効果
Brandon A Rodriguez1, Massimiliano Delferro, Tobin J Marks
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, USA.
Journal of the American Chemical Society
|April 9, 2009
まとめ
新しい二金属ニッケル触媒 (FI(2) -Ni(2) は,単金属のバージョンと比較して,エチレンポリメリゼーションにおける強化された活性と分岐を示しています. これらの触媒はまた,極性モノマーとの共ポリメリゼーションを改善し,極性溶媒を許容します.
科学分野:
- 有機金属化学 有機金属化学
- ポリマーサイエンスの科学
- カタリシス カタリシス カタリシス
背景:
- ニッケル触媒はオレフィンポリメリゼーションに不可欠です.
- 調節触媒の構造は,ポリマーの性質と反応性を変化させることができます.
- バイメタリック複合体は,ユニークな協力効果を提供します.
研究 の 目的:
- 新しい二金属ニッケル触媒を合成し,特徴づけること.
- エチレンホモポリメリゼーションとコポリメリゼーションにおける性能を評価する.
- バイメタリック構造が触媒活性,選択性,溶媒耐性に対する影響を調査する.
主な方法:
- 二金属および単核ニッケル複合体の合成.
- スペクトロスコピーおよび分析技術を用いた特徴付け.
- 様々なモノマーでエチレンホモポリメリゼーションとコポリメリゼーションの研究.
- 反応機構とポリマーマイクロ構造の調査.
主要な成果:
- FI(2) -Ni(2) 触媒は,単核類比よりもエチレンホモポリメリゼーションにおいてより高い活性と分岐を示します.
- 極性ノルボルネンおよびアクリラートとの共ポリメリゼーションは,FI(2) -Ni(2) 触媒によって著しく強化されます.
- FI(2) -Ni(2) 触媒は,アセトンや水などの極性溶媒に対する耐性を示しています.
- エチレン濃度は枝分かれと形態学に影響する.
結論:
- ビメタリックニッケル触媒 (FI(2) -Ni(2) は,オレフィンポリメリゼーションおよび共ポリメリゼーションにおいて優れた性能を提供します.
- バイメタリック系における協力効果は,コモノマー組み込みと溶媒耐性を高めます.
- これらの触媒は,新しい機能化されたポリオレフィンへの経路を提供する.
関連する概念動画
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