リバーシブル・アディション・フラグメンテーション・チェーン・トランスファー・ポリメリゼーションにおける速度遅延の普遍性
Kate G E Bradford1, Leilah M Petit1, Richard Whitfield2
1Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056, United States.
Journal of the American Chemical Society
|October 18, 2021
まとめ
速度遅延は,特定の連鎖移転剤またはモノマー活動に関係なく,可逆的加法断片化鎖移転 (RAFT) ポリメリゼーションにおいて一般的な問題である. この現象は普遍的な関係によって記述され,RAFTのプロセス運動学の理解を簡素化することができる.
科学分野:
- ポリマー化学
- ラジカルポリメリゼーション
背景:
- リバーシブル・アディション・フラグメンテーション・チェーン・トランスファー (RAFT) ポリメリゼーションは,リバーシブル・デアクティベーション・ラジカル・ポリメリゼーション (RDRP) の重要な方法である.
- 理想的な運動から逸脱する速度遅延は,RAFTプロセスで頻繁に観察されます.
研究 の 目的:
- RAFTポリメリゼーションにおける速度遅延の流行と根本的なメカニズムを調査する.
- 速度遅延は,ディチオベンゾ酸鎖移転剤 (CTA) とより活性なモノマー (MAM) に特異的か,またはより広範な現象であるかを決定する.
主な方法:
- 様々なCTA (トリチオカルボネート,キサンテート) を使ったRAFTポリメリゼーションシステムの探索
- ポリメリゼーションデータを分析するために,単純なゆっくりとした断片化と中間的な根絶を含む運動モデルを適用する.
主要な成果:
- 異なるCTA型 (トリチオカルボネート,キサンテート) と異なるモノマー活動において,速度遅延が観察されました.
- 単一の普遍的な関係は,すべてのテストされたシステムで観察された速度遅延を効果的に記述します.
結論:
- RAFTポリメリゼーションの速度遅延は,特定のCTAタイプまたはモノマー活動に限定されない普遍的な現象です.
- 速度遅延の重度は異なるが,一貫してモデル化され,RAFTポリメリゼーション運動の予測と制御を簡素化することができる.
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