在结构化流体的脱过程中,自发组装冷凝网
Yuma Morimitsu1, Christopher A Browne1, Zhe Liu1
1Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, PA 19104.
概括
经过液-液相分离的结构性流体形成独特的丝网,而不是球体. 这种新的凝结物网络形成为材料科学和模式形成提供了新的途径.
科学领域:
- 材料科学 材料科学 材料科学
- 流体动力学 流体动力学
- 软物质物理学 软物质物理学
背景情况:
- 液-液相分离在自然界和工业中很常见.
- 同源流体在脱混合过程中形成球状滴.
- 在相位分离过程中结构化流体的动力学还不太清楚.
研究的目的:
- 为了研究从溶剂中脱离中原体的脱动态.
- 观察和描述结构化流体中的凝结物的形态.
- 了解驱动凝结体网络形成的机制.
主要方法:
- 在一个中位素-溶剂系统中观察液-液相分离.
- 显微镜技术可视化凝结物形态和动态.
- 导线延长,加密和网络组装的分析.
主要成果:
- 脱离混合的中质体形成了延长的细丝,而不是球体.
- 细丝缩成凸起的圆盘,以减少弹性自由能量.
- 细丝的收缩和直导致了一个分支的网络结构.
结论:
- 结构流体表现出独特的相隔动态,形成丝网.
- 凝结体网络的形成是由于需要缓解内部中相变形的扭曲而引起的.
- 这种现象为有针对性的图案形成和材料模板设计开辟了可能性.
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