1,3-ブタジエンのエチレンとの二重サイト交互サイクロコポリメリゼーション
Tong Neo Choo1, Robert M Waymouth
1Department of Chemistry, Stanford University, Stanford, CA 94305-5080, USA.
Journal of the American Chemical Society
|September 17, 2004
まとめ
この研究では,アンサ-メタロセンの触媒を用いたエチレンと1,3-ブタジエンの共ポリメリゼーションを調査しました. 独特の周期構造を持つ新しいサイクロコポリマーが達成され,モノマー挿入のための二重サイトメカニズムを示唆しました.
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:
- アンサ-メタロセンの触媒は,オレフィンポリメリゼーションに不可欠です.
- コポリマーアーキテクチャの制御は,ポリマー科学における重要な課題です.
研究 の 目的:
- 一連のアンサ-メタロセンの触媒を用いて,エチレンと1,3-ブタジエンの共ポリマー化を調査する.
- 新しい共ポリマー構造の形成の背後にあるメカニズムを解明する.
主な方法:
- 使用されたアンサメタロセンの触媒は,Me2Si ((Cp) ((9-Flu) ZrCl2 (1),Me2Si ((1-Ind) ((9-Flu) ZrCl2 (2),およびMe2Si ((9-Flu) 2ZrCl2 (3) である.
- メチルアルミノキサン (MAO) をコカタリストとして使用.
- 合成したコポリマーの組成と構造を分析した.
主要な成果:
- Catalyst 2/MAOは,2つのエチレン単位と1つのブタジーン単位の特定の比率を持つサイクロコポリマーを生成しました.
- メチレンで分離された1,2連鎖のサイクロペンタン単位を特徴とする新しい周期的構造が特定されました.
- 交替サイクロコポリメリゼーションの高い選択性が観察されました.
結論:
- 観測された高いブタジエンの含有量と選択性は,二重サイトメカニズムを示しています.
- エチレンとブタジエンは,触媒内の異なる調整部位で鎖に繋がっている可能性が高い.
- この研究は,設計に合わせたアーキテクチャを持つポリマーを設計するための新しい道を開きます.
関連する概念動画
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