一个人造的分子陪伴者:具有可伸缩轴的聚伪-罗他森
Motofumi Osaki1, Yoshinori Takashima, Hiroyasu Yamaguchi
1Department of Macromolecular Science, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan.
Journal of the American Chemical Society
|November 2, 2007
概括
在聚-达-瓦莱洛拉克链上线的循环德克斯特林 (CD) 启动了-瓦莱洛拉克 (delta-VL) 的固态聚合. 这种聚伪-罗他森形成对于聚合是至关重要的,它就像一个人造的陪伴者.
科学领域:
- 聚合物化学 聚合物化学
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
背景情况:
- 聚伪罗塔是通过将循环分子连接到聚合物链上而形成的超分子结构.
- 环极素 (CDs) 以其形成包容复合体和作为宿主的能力而闻名.
- 固态聚合提供受控合成和独特的材料特性.
研究的目的:
- 调查循环德克斯 (CDs) 在启动三角黄素 (delta-VL) 固态聚合过程中的作用.
- 探索聚合过程中的多伪罗塔克桑的形成和功能.
- 了解由CDs介导的聚合启动机制.
主要方法:
- 合成具有β-环氧素 (β-CD) 末端组的多--烯酸乳链 (标记为1).
- 在聚合物链上进行各种CD (alpha-CD,beta-CD,2,6-di-O-methyl-beta-CD) 的线程.
- 德尔塔-VL.的固态聚合实验.
- 使用粉末X射线衍射和固态NMR光谱学的表征.
- 使用阿达曼坦 (Ad) 进行抑制研究,以探测β-CD腔的可访问性.
主要成果:
- 嵌入到多 ((delta-valerolactone) 上的CD在固态中启动了delta-VL聚合,形成了多伪rotaxanes.
- 没有线程CD的聚合物链没有显示出聚合能力.
- 阿达曼坦阻塞了β-CD腔,抑制了聚合,证实了β-CD在启动中的作用.
- 聚伪罗塔克桑的形成对于启动delta-VL聚合是必不可少的.
- 线程CD作为人工伴侣,折叠聚合物链进行聚合.
结论:
- 在CD被接到聚合物链上时,聚伪-罗塔克桑的形成是启动固态delta-VL聚合的关键要求.
- 贝塔-CD腔在聚合过程中起着至关重要的作用,作为模板和启动器.
- 磁盘作为人工伴侣,指导聚合物链形状,以实现高效的聚合.
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