エノールエーサーは環開きメタテシスポリメリゼーションに有効なモノマーである.分解可能および分解可能ポリウランの合成
1Department of Chemistry , Stanford University , Stanford , California 94305 , United States.
Journal of the American Chemical Society
|December 28, 2019
まとめ
研究者は,サイクルエノールエーサーのリング開きメタテシスポリメリゼーション (ROMP) を達成し,新しい分解可能なポリエノールエーサーを作成しました.このブレークスルーは,持続可能な材料ソリューションを提供する触媒リサイクルとポリマー脱ポリメリゼーションを可能にします.
科学分野:
- ポリマー化学
- 有機合成
- 材料科学
背景:
- エノールエーサーは通常,グラブス触媒を消し,ポリメリゼーションでの使用を制限する.
- ルテニウムアルキリデン複合体は,電子に富んだオレフィン転移のために活性化し続けることができます.
研究 の 目的:
- 循環エノールエーサーのリング開きメタテシスポリメリゼーション (ROMP) を実証する.
- 分解性および脱ポリマー性ポリエーテルを開発する.
- 触媒の無効化と除去の方法を確立する.
主な方法:
- グラブス触媒でROMPのモノマーとして2,3-ジヒドロフーランを使用した.
- ポリマー分子の重量を制御し,イニシアター・ロードとチェーン・トランスファー・エージェントを使用する.
- 触媒除去のためのH2O2酸化プロトコルを開発した.
主要な成果:
- サイクリックエノールエーテルに対するROMPの最初の例が達成され,ポリ・ディヒドロフーランが得られました.
- 完全な地域規則性と制御可能な分子量を持つポリマーを製造した.
- 触媒の無効化,除去,そしてその後のポリマー脱ポリマー化/分解が実証されている.
結論:
- サイクルエノールエーターは,ROMPの活力のあるモノマーであり,新しい分解性ポリマーを生成します.
- 合成されたポリ・ディヒドロフーランは,モノマーに再利用可能であり,小分子に分解可能である.
- この研究は,エノールエーテルモノマーを用いた持続可能なポリマー開発の新たな道を開きます.
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