(cyclopentadienyl) (((ketimide) titanium (((IV) 複合体によって触媒化されたスタイレンとエチレンの生協ポリメリゼーション--MAO触媒システム
1Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0101, Japan.
Journal of the American Chemical Society
|June 30, 2005
まとめ
エチレンとスタイレンの生体共ポリメリゼーションは,特定のチタン触媒とメチルアルミノキサン (MAO) コカタリストを使用して達成されました. この新しい方法は,従来のホモポリメリゼーション技術とは異なり,制御されたポリマー合成を可能にします.
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
背景:
- リビングポリメリゼーション技術は,制御されたアーキテクチャを持つポリマーの合成に不可欠です.
- エチレンとステロンの共ポリメリゼーションは,制御された鎖の成長を達成する上で課題を提示します.
研究 の 目的:
- 特定のチタン触媒を用いて,エチレンとステロンの生体共ポリメリゼーションを調査する.
- カタリスト構造がコポリメリゼーション行動とスタイレン組み込みに及ぼす影響を理解する.
主な方法:
- Cp*TiCl2 (((N=CtBu2) 触媒とメチルアルミノキサン (MAO) 協触媒を用いたエチレンとステロンの共ポリマー化.
- 合成されたポリエチレン-コスタイレンを分析して,ポリマーの構造とスタイレンを含有量を決定する.
主要な成果:
- 特定のチタン触媒システムは,エチレンとスタイレンの生体共ポリメリゼーションを示した.
- この触媒で,エチレンとステロンの同ポリメリゼーションは生体的に進行しなかった.
- 生成したコポリマーにはスタイレン重複ユニットが観察されず,鎖移転の阻害を示した.
結論:
- MAOを含むCp*TiCl2(N=CtBu2) 触媒システムは,生エチレン・ステレン共ポリメリゼーションを可能にします.
- この独特な振る舞いは,スタイレン挿入は,主鎖に組み込まれていなくても,チェーン転送メカニズムに影響を与える可能性があることを示唆しています.
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