テレケリックポリマーの光と熱による可逆的線形サイクルトポロジック変換
Takuya Yamamoto1,2, Sakyo Yagyu1, Yasuyuki Tezuka1
1Department of Organic and Polymeric Materials, Tokyo Institute of Technology , O-okayama, Meguro-ku, Tokyo 152-8552, Japan.
Journal of the American Chemical Society
|February 27, 2016
まとめ
この研究では,光または熱を用いた可逆的なポリマートポロジー変換が示されています. ポリマーは線形と循環形の間を切り替えることができ,より低い分子量で変換が速くなります.
科学分野:
- ポリマー化学
- 材料科学
- 超分子化学
背景:
- 高度な材料の特性には ポリマートポロジーの制御が不可欠です
- 刺激に反応するポリマーを開発することで ダイナミックな素材の設計が可能になります
- 光化学反応はポリマーの変換を正確に制御します.
研究 の 目的:
- ポリマーのリバーシブルな線形サイクルトポロジック変換を調査する.
- この変換に分子量とエンドグループ化学の影響を調査する.
- 光と熱がトポロジカルな変化を 引き起こすことを示します
主な方法:
- アントリルまたはクマリニル末端グループを持つテレケリックポリマーの合成
- 光化学反応 (365nmと254nmでのUV照射) でサイクル化と線形化が誘発される.
- 熱処理 (150 °C) で,サイクルポリマーを線形に戻す.
- 核磁共振 (NMR),サイズ排除染色体 (SEC),マトリックスアシストレーザー溶解/イオン化飛行時間質量スペクトロメトリー (MALDI-TOF MS) を用いた特徴化.
主要な成果:
- ポリエチレン酸化物とポリテトラヒドロフーランのテレケリックをアンチリル末端グループで成功して合成した.
- 水性および有機的媒体の両方で,アンチル終末ポリマー (Ant-CO2-PEO) の効率的な光誘導サイクリングが実証されています.
- 周期性ポリマーの線形状態への定量的な熱逆転が示され,再現性を確認した.
- コマリニル終末ポリマー (Cou-PEO) の溶媒依存サイクル化が観察され,水害性相互作用の役割が強調された.
結論:
- リバーシブル・リニア・サイクル・トポロジック・コンバージョンは,ヒドロフィール・ポリマーとヒドロホビック・ポリマーの両方で達成可能である.
- サイクリングの効率は,ポリマーの分子量,エンドグループ化学,溶媒環境に依存します.
- 光と熱は反転可能なトポロジックスイッチングの有効なトリガとして機能し,ダイナミックなポリマーシステムへの道を開きます.
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