只有在五个单体重复单位内显示液态准晶,A15和 σ 弗兰克-卡斯珀阶段
Marian N Holerca1, Dipankar Sahoo1, Benjamin E Partridge1
1Roy & Diana Vagelos Laboratories, Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104-6323 , United States.
Journal of the American Chemical Society
|November 22, 2018
概括
研究人员合成了一种新型的多-2-zoline,它可以自组织成液态准晶 (LQC) 和两个弗兰克-卡斯珀相. 这一发现为研究软物质自组织成复杂的周期性和准周期性数组提供了一个模型系统.
科学领域:
- 软物质物理学
- 材料科学
- 聚合物化学
背景情况:
- 液态半晶 (LQC) 和弗兰克-卡斯珀相 (Pm3̅n立方和P42/mnm四边形) 是各种软物质系统中发现的复杂的自组结构.
- 之前的研究在和块共聚物中发现了这些阶段,但在多2-中没有.
- 已知具有较短链 (n=14-16) 的基聚二氧化形成了弗兰克-卡斯珀相.
研究的目的:
- 合成和表征一种能够形成LQC的基化聚2-氧.
- 为了研究不同程度的聚合 (DP) 的多-2-素的自我组装行为.
- 从单个聚合物系统中探索LQC和弗兰克-卡斯珀相的形成.
主要方法:
- 合成了带有n=17个链的丹德罗化多-2-zoline.
- 自组装阶段的结构和逆结构分析.
- 在狭窄的DP范围内观察相位行为 (5 ≤ DP ≤ 10).
主要成果:
- 一种具有n=17的新型多-2-zoline被合成并自组织成LQC,Pm3̅n立方和P42/mnm四角相.
- 从相同的聚合物中观察到所有三个不同的阶段在狭窄的DP范围内 (5 ≤ DP ≤ 10).
- 这是首次在多-2-zoline系统中报告LQC形成的情况.
结论:
- 一个单一的多二氧化链可以在有限的DP范围内自组织成周期性和准周期性结构 (LQC,弗兰克-卡斯珀相).
- 这些发现引发了关于驱动这些复杂阵列的自我组织机制的根本问题.
- 这种系统是软物质自组装到弗兰克-卡斯珀和相关结构的理论研究的宝贵模型.
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