オルガノランタニド触媒合成による,フォスフィン終末ポリエチレンの合成
Amber M Kawaoka1, Tobin J Marks
1Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3113, USA.
Journal of the American Chemical Society
|October 8, 2004
まとめ
この研究は,オルガノランタニド媒介による水リン酸化とエチレンポリメリゼーションを組み合わせています. オレフィンポリメリゼーションにおける効率的なチェーン転送剤としてディフェニルフォスフィンを導入し,機能化されたポリマーを生成します.
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:
- オレフィンポリメリゼーションは,ポリマー生産の礎石です.
- 機能的エンドグループを持つ制御されたポリメリゼーションプロセスの開発は,先進的な材料にとって極めて重要です.
- オルガノランタニド複合体は,オレフィン変換にユニークな触媒特性を提供します.
研究 の 目的:
- オーガノランタニド媒介による水リン酸化とエチレンポリメリゼーションを組み合わせる.
- シングルサイト触媒システムにおけるチェーン転送剤としてのディフェニルフォスフィンの役割を調査する.
- 制御された分子量を持つディフェニルフォスフィン末端ポリエチレンを合成するために.
主な方法:
- ハイドロフォスフィネーションとエチレンポリメリゼーションを組み合わせた触媒サイクルを使用しました.
- 1H,13C,および31P NMR,ゲル浸透染色体 (GPC),および差分スキャニングカロメトリー (DSC) を使用して,結果のポリマーを特徴付けました.
- ポリマーの性質をモデル化合物である1-eicosyldiphenylphosphine oxideと比較した.
主要な成果:
- ポリメリゼーション/チェーン転送プロセスで高い触媒活性 (107 gポリマー/mol Ln.atmエチレン.h)) を達成した.
- 狭いポリ分散が観察され,ポリマーの成長が制御されていることを示しています.
- ポリエチレン分子量とディフェニルフォスフィン濃度の間には逆の関係があることが示され,チェーン転送が確認されました.
結論:
- オーガノランタニドを用いた水素酸化とポリメリゼーションを成功裏に結合した.
- 確立されたディフェニルフォスフィンは,単一サイトf-およびd電子の金属媒介オレフィンポリメリゼーションにおける効果的な鎖移転剤である.
- この研究は,オレフィンポリメリゼーションにおける制御された機能化のための電子豊富なフォスフィンの使用を先駆けて行っている.
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