ポリメリゼーション触媒におけるペンタフローロスルファニル置換物
Philip Kenyon1, Stefan Mecking1
1Chemical Materials Science, Department of Chemistry, University of Konstanz , Universitätsstrasse 10, 78457 Konstanz, Germany.
Journal of the American Chemical Society
|September 19, 2017
まとめ
有機金属触媒に新しいペンタフルオルスルファニル基を導入すると,エチレンポリメリゼーションが強化されます. この技術革新により,水中でも枝分かれが少ない超高分子量線形ポリエチレンが得られます.
科学分野:
- 有機金属化学
- ポリマー科学
背景:
- オレフィンポリメリゼーションには有機金属触媒が不可欠である.
- ポリマーの分子量と分岐を制御することは 重要な課題です
- ベータ水素の除去は,鎖の終結と分岐の主要な経路です.
研究 の 目的:
- 高度な電子取り除くペンタフローロスルファニル群の有機金属触媒への影響を調査する.
- 超高分子量 線形ポリエチレンの合成を研究する
- 水中のエチレンの直接的なポリメリゼーションを可能にする.
主な方法:
- ペンタフルオルスルファニル置換剤を含むNi (II) サリシラルディミネート複合体の合成.
- これらの改良された触媒を用いたエチレンポリメリゼーション実験.
- ポリマーの分子量,分岐,形状の分析
主要な成果:
- ペンタフローロスルファニル群はベータ水素の排出を著しく減少させた.
- 触媒は高分子量と低分岐のポリエチレンを生成しました
- 水中のエチレンの直接的ポリメリゼーションにより,線形ポリエチレンのナノ結晶分散が得られました.
結論:
- ペンタフローロスルファニル基は,エチレンポリメリゼーションにおける触媒性能を向上させるのに有効な代替剤である.
- ベータ水素の除去抑制は,超高分子量の線形ポリエチレンを得るための鍵です.
- 開発された方法は,水中の環境に優しいポリメリゼーションを可能にします.
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