リング開きポリメリゼーションにおけるエピメリゼーションを排除するためのシナジェティック・オルガノカタリスは,ステレオレギュラー・イソタクティック・ポリエステルの合成を可能にします
Maosheng Li1,2, Yue Tao1,3, Jiadong Tang1,3
1Key Laboratory of Polymer Ecomaterials , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Renmin Street 5625 , Changchun 130022 , People's Republic of China.
Journal of the American Chemical Society
|December 5, 2018
まとめ
この研究は,O-カルボキシアン水素 (OCA) のリング開きポリメリゼーションのための新しい二機能有機触媒を導入します. この方法では,モノマー・ラセミゼーションなしで高同位性ポリエステルを得て,機能性ポリマーの持続的な合成を可能にします.
科学分野:
- ポリマー化学
- 有機触媒
- 材料科学
背景:
- O-カルボシアン水素 (OCA) のリング開きポリメリゼーション (ROP) は,機能的なポリエステルへのアクセスを提供します.
- 既存の ROP 方法はしばしばモノメア・ラセミゼーションを引き起こし,ステレオレギュラーポリマーの合成を妨げます.
- エピメリゼーションを防ぐ触媒の開発は,制御されたポリエステル合成に不可欠です.
研究 の 目的:
- OCAポリメリゼーションのための新しい二機能単分子有機触媒を開発する.
- エピメリゼーションなしでOCAの選択的なROPを達成するために.
- 高等性ポリエステルを合成し,その性質を調査する.
主な方法:
- 双機能単分子有機触媒の設計と合成
- O-カルボシアンヒドリド (OCA),特にマンデリック酸OCA (manOCA) のリング開きポリメリゼーション
- 分子重量と戦術性を含む結果のポリマンデリック酸 (PMA) の特性.
- PMAステレオ複合体の形成と特徴付け
主要な成果:
- 双機能触媒は,最小限のエピメリゼーションでマノカの選択的なROPを可能にしました.
- 制御された分子量 (最大19. 8kgmol−1) を有する高同位性ポリマンデリック酸 (PMA) が合成された.
- PMAエナチオメルの最初の結晶型ステレオ複合体が形成され,融点は約150°Cであった.
- 触媒は水分安定性,再利用性,そして使いやすさを示した.
結論:
- 新しい二機能器官触媒は,OCAsのステレオ選択ROPのための効果的な経路を提供します.
- このアプローチにより,ステレオレギュラー機能ポリエステルの持続可能でスケーラブルな合成が可能になります.
- 結晶型ステレオ複合体を形成する能力は,機能的なポリエステル材料のための新しい道を開きます.
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