耐久性のあるNi (II) フォスフィノフェノラト触媒によるエチレンの生水マイクロエムルションポリメリゼーション
Fei Lin1, Tobias O Morgen1, Stefan Mecking1
1Chair of Chemical Materials Science, Department of Chemistry, University of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany.
Journal of the American Chemical Society
|December 1, 2021
まとめ
新しいニッケル触媒は生エチレンポリメリゼーションを可能にし,水中の狭い分布を持つ超高分子量ポリエチレンを生成します. この突破は鎖の移転を最小限に抑えて ポリマーの合成を水性媒体で進めます
科学分野:
- ポリマー化学
- 有機金属化学
- 材料科学
背景:
- P,O-ケラートされたNi (II) 複合物を用いたエチレンポリメリゼーションは,競合する鎖移転イベントのために,通常,低分子量ポリマーを生成します.
- 制御された構造を持つ高分子量ポリマーの達成は,ポリメリゼーション触媒における課題である.
研究 の 目的:
- 生体エチレンポリメリゼーションのための新しいニッケル触媒システムを開発する.
- 水性環境で超高分子量ポリエチレンの製造の可能性を調査する.
- 伝統的なポリメリゼーション方法におけるチェーン転送に関連する制限を克服する.
主な方法:
- 大量の置換されたフォスフィノフェノラトニウム (Ni) 複合体の合成と特徴づけ
- 合成したニッケル複合体のマイクロエムルションを用いたエチレンの水性ポリメリゼーション (触媒3).
- ポリマーの分子量分布 (Mw/Mn) と分子量 (最大2 × 10^6) の分析
主要な成果:
- 開発されたフォスフィノフェノラトニウムの複合体 (3) は生体ポリメリゼーションの振る舞いを示し,鎖の移転を著しく減少させた.
- 超高分子量 (最大2 × 10^6) と狭い分子量分布 (Mw/Mn = 1.021.34) を有するポリエチレンが成功裏に生産されました.
- ポリメリゼーションは水性ナノ粒子分散で実施され,触媒は70°Cまで安定性と活性を維持した.
結論:
- 大量のフォスフィノフェノラトニウム (Ni) 複合体は,水中の生エチレンポリメリゼーションの効果的な触媒である.
- このアプローチは,分子量分布を正確に制御した超高分子量ポリエチレンの合成を可能にします.
- 水性環境における触媒の安定性と活性により,持続可能で効率的なポリマー生産の道が開けます.
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