1,5-ヘクサジエンの挿入/異体化ポリメリゼーション:機能プロピレンコポリマーとブロックコポリマーの合成
Phillip D Hustad1, Geoffrey W Coates
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, NY 14853, USA.
Journal of the American Chemical Society
|September 26, 2002
まとめ
タイタンの触媒は1,5-ヘクサディエンのポリメリゼーションを可能にし,ユニークなビニルテトラメチレン単位を持つポリマーを生成します. この発見により,ビニール機能のポリプロピレンコポリマーおよびブロックコポリマーの作成が容易になりました.
科学分野:
- ポリマー化学のポリマー化学について
- オーガノメタリック触媒.
背景:
- ビス ((フェノキシイミン) タイタニウム複合体は,オレフィンポリメリゼーションの効果的な触媒である.
- 1,5-ヘクサジエンのポリメリゼーションは,典型的には,特定のマイクロ構造を持つポリマーを生成します.
研究 の 目的:
- 1,5-ヘクサジエンのポリメリゼーションを bis ((フェノキシミン) タイタン触媒を用いて調査する.
- 予期せぬポリマーマイクロ構造の形成の背後にあるメカニズムを解明する.
- この触媒システムの応用を,機能化された共ポリマーを合成する上で探求する.
主な方法:
- 1,5-ヘクサジエンの触媒的ポリメリゼーションは,bis ((フェノキシミン)) タイタン触媒を用いて行われます.
- 発現したポリマーの微細構造分析は,スペクトル検査技術を用いて行われます.
- コポリメリゼーションおよびブロックコポリメリゼーション反応の調査.
主要な成果:
- ポリメリゼーションにより,予想されるメチレン-1,3-サイクロペンタン単位と予想外の3ビニルテトラメチレン単位の両方を含んだポリマーが生成されました.
- 観察された微細構造の形成を説明するために,反応機構が提案されました.
- 触媒システムは,ビニル機能ポリプロピレンコポリマーと,低ポリ分散性のブロックコポリマーを合成するために成功裏に適用されました.
結論:
- ビス・フェノキシイミン・チタンの触媒システムは,1,5-ヘクサジエンの異常なポリメリゼーション経路を駆動する.
- この触媒システムは,機能化されたポリオレフィンと,制御された構造を持つブロックコポリマーを生産するための新しい経路を提供します.
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