固态区块共聚合物的超分子聚合,辅助于选择性形成纳入晶体
Silvia Bracco1, Angiolina Comotti, Lisa Ferretti
1Department of Materials Science, University of Milano Bicocca, Via R. Cozzi 53, 20125 Milano, Italy.
Journal of the American Chemical Society
|May 20, 2011
概括
研究人员使用宿主分子和triblock共聚合物创建了有组织的2D纳米晶体. 这种超分子自我组装选择性地包括乙烯氧化物块,通过非共价相互作用形成坚固的材料.
科学领域:
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
- 聚合物科学 聚合物科学
背景情况:
- 像聚乙烯氧化物-b-氧化物-b-乙烯氧化物 (EO) (n) PO (m) EO (n)) 这样的triblock共聚合物提供了多功能构建块.
- 超分子自我组装为通过非共价相互作用创造有序材料提供了一条途径.
- 能够形成纳入化合物的宿主分子可以指导客分子的组装.
研究的目的:
- 为了研究与宿主分子的triblock共聚物的超分子自我组装.
- 形成具有定义结构和特性的2D纳米晶体.
- 了解控制自组装过程的驱动力和相互作用.
主要方法:
- 无溶剂的机械化学方法和热处理用于自组装.
- 在现场同步X射线衍射监测结构形成.
- 固态NMR ((1) H-(13) C, (1) H MAS) 来探测主机-客体相互作用和拓.
- 开始计算 (HF-GIAO/DGDZVP) 来分析磁性敏感性和分子间相互作用.
主要成果:
- 通过在宿主分子中选择性地包含乙烯氧化物 (EO) 块来形成包含2D纳米晶体.
- 氧化物 (PO) 块的阶段分离导致交替的晶状片和无形层.
- 证明合作的非共价性分子间相互作用和CH···π相互作用作为驱动力.
- 证实了亲密的宿主-客人相互作用和强大的超分子架构.
结论:
- 结合区块共聚合物和形成酸盐的宿主分子的策略使得有组织材料的制造成为可能.
- 选择性非共价相互作用是指导复杂聚合物架构的自我组装的关键.
- 由此产生的超分子架构由于特定的宿主-客人相互作用而表现出增强的稳定性.
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