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Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
Published on: December 16, 2022
精密ポリエチレン:アルキル分岐の大きさの関数として形態の変化
Giovanni Rojas1, Bora Inci, Yuying Wei
1Center for Macromolecular Science and Engineering, The George and Josephine Butler Polymer Research Laboratory, Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, USA.
Journal of the American Chemical Society
|November 7, 2009
まとめ
精密分岐ポリエチレン合成により,結晶形状の制御が可能になります. 枝の大きさは,それが結晶単位細胞に統合するかどうかを決定し,ポリマーの性質に影響を与えます.
科学分野:
- ポリマー化学のポリマー化学について
- マテリアルサイエンス 材料科学
- クリスタログラフィーです.
背景:
- ポリエチレンの従来の連鎖ポリメリゼーションは,ポリマーの微細構造に対する制御を制限する.
- メタテシスポリコンデンサーションは,精密に設計されたポリマーアーキテクチャへの経路を提供します.
- ポリエチレン形態学における分岐の影響を理解することは,高度な材料の開発に不可欠です.
研究 の 目的:
- メタテシスポリコンデンサスを用いてポリエチレン結晶形状に対する精密ブランチの影響を調査する.
- 枝の大きさと位置をユニット細胞構造と相行動 (結晶と無形) と相関させる.
- モルフォロジー制御とポリマーの熱特性との関係を調査する.
主な方法:
- 異なる精度分岐 (メチルからアダマンチルまで) を有するユニークな対称性ダイエネモノマーの合成.
- リングオープニングメタテシスポリメリゼーション (ROMP) に続いて水素化を行い,精密分岐ポリエチレンを生産します.
- 先進的な分析技術を用いたモノマー,中間物質,最終ポリマーの包括的な構造的特徴付け.
主要な成果:
- メタテシスポリコンデンセーションにより,ポリエチレン結晶単体細胞構造の正確な制御が可能になり,オーソロンビックからトリクリニックにシフトしました.
- ポリマーの形態は調整可能であり,小枝 (メチル,エチル) が単細胞に組み込まれ,より大きな枝 (プロピル以上) は除外された.
- ユニットセルから除外された枝は,枝の大きさに関係なく,アダマンチル群であっても,融解温度に影響を与えなかった.
結論:
- メタテシスポリコンデンサーションで合成された精密分岐ポリエチレンは,結晶形質に対する前例のない制御を提供します.
- 枝の大きさは,ポリエチレンユニットセルに含まれるか否かを決定する重要な決定因子です.
- この形態学的制御戦略は,ポリエチレンにおける分岐特性から熱的性質を切り離す方法を提供する.
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