ステレオレギュラーアリファティックポリエステルのステレオ複合化:単一ステレオセンター逆転によるアモルフから半結晶ポリマーへの変化
Yanay Popowski1, Yiye Lu2, Geoffrey W Coates2
1Department of Chemistry, Washington University in St. Louis, One Brookings Hall, Campus Box 1134, St. Louis, Missouri 63130-4899, United States.
Journal of the American Chemical Society
|April 27, 2022
まとめ
研究者はPLA以外の生物分解性ポリエステルの ステレオ複合性を調査した. エポキシドとアンヒドリドの特殊なキラル組み合わせにより,熱性能が向上した半結晶ポリマーが得られ,先進的なポリマー材料のための新しい経路が示されました.
科学分野:
- ポリマー化学
- 材料科学
- ステレオ化学
背景:
- ステレオコンプレクセーションは,キラルポリマーの鎖の共結晶化によってポリマーの性質を高めます.
- PLAを除く生物分解性ポリエステルステレオ複合物は未十分に研究されている.
- ポリマーの微細構造とステレオ複合性の関連は,特にキラル共ポリマーでは,明確にする必要がある.
研究 の 目的:
- 新しい生物分解性ポリエステルのステレオ複合性を調査する.
- ポリマーの微細構造と特性に対するキラル構造の組み合わせの影響を調査する.
- ステレオ複合化により熱安定性を高める半結晶共ポリマーを開発する.
主な方法:
- 非対称性キラルアンヒドリド (CPCA) のエナンチオメアの解像度
- 様々なキラルエポキシドとアンヒドリドからポリエステルを作るための金属触媒リング開封共聚化 (ROCOP).
- エナティオメア共ポリマーを等分量混合することによってステレオ複合体を製造する.
主要な成果:
- エポキシドとアンヒドリドの特定のキラル結合は半結晶性を誘導する.
- シングル・ステレオセンターの逆転により,コポリマーの結晶性が無形から半結晶に変化した.
- ステレオコンプレックスは溶解温度が上昇した (約 20 °C以上) と比較する.
- 最適化されたステレオコンプレックスは,238 °Cの高い融解温度を達成した.
結論:
- モノメアの構成要素におけるキラル選択は,ROCOPによる半結晶生物分解性ポリエステルの達成に不可欠である.
- これらの新しいコポリマーのステレオコンプレクセーションにより,熱特性が大幅に向上します.
- この研究は,特化した微細構造を持つ高性能生物分解性ポリマーを設計するための新しい戦略を提供します.
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