アクリラートとイソシアニドの制御された過激なポリメリゼーションは,新しい共ポリマーに分解可能な機能をインストールします
Lejla Čamdžić1, Erin E Stache1
1Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States.
Journal of the American Chemical Society
|September 5, 2023
まとめ
研究者はイソシアン化物を用いて 光分解性ポリマーを作る 新しい方法を開発しました このアプローチは,調節性特性と熱安定性の高い非交代性ポリケトンを生成し,既存の技術に多用途の代替品を提供します.
科学分野:
- ポリマー化学
- 材料科学
- 光分解性ポリマー
背景:
- ケトン群をポリマーバックボーンに組み込むことは,光分解性を達成するための既知の戦略です.
- 現在の方法は主にエチレン-一酸化炭素共聚化に限定され,材料の多様性を制限しています.
- 調整可能な特性を有する光分解性ポリマーを作成するために,代替の共聚合戦略が必要である.
研究 の 目的:
- 光分解性ポリマーの共ポリマー化における一酸化炭素の代替品としてアイソシアニドの使用を調査する.
- 熱的特性を維持または強化した非交代性ポリケトンを合成する.
- 多様なポリマーマイクロ構造にアクセスするための単一の共ポリマー化戦略を確立する.
主な方法:
- コバルト媒介によるアクリラートとアイソシアニドの根性ポリメリゼーションで,交代しないポリ ((アクリラート-コ-アイソシアニド) コポリマーを合成する.
- コポリマー組成を制御するモノメアの組み込み比を調節する.
- β-エナミンのエステル中間物質の水解により,非交代性ポリケトン微構造が得られる.
主要な成果:
- 調節可能なモノマーを組み込む非交代型ポリ ((アクリルコイソシアン酸) の合成に成功した.
- 動的β-アミネエステルである運動産物は,β-エナミネエステルにタウトメリゼスし,水解により標的ポリケトンが得られる.
- 熱特性を含むポリマーの性質は,モノメアの組み込み度に基づいて調整可能であった.
- ポリアクリルコイソシアン化物とポリアクリルコイソケトンの両方が, 390 nm の光に曝露すると光分解性が示され,鎖裂けを引き起こした.
結論:
- アイソシアン化基の共ポリメリゼーションは,調節性特性を有する非交代性ポリケトンへの多用途な経路を提供します.
- この方法は,熱安定性を維持または強化する光分解性ポリマーにアクセスできます.
- 開発された戦略は,単一の共聚合プロセスから多様なポリマーマイクロ構造の合成を可能にします.
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