电荷不对称性抑制了多电解质复合凝聚的凝聚动力学
Shensheng Chen1, Zhen-Gang Wang1
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Physical review letters
|December 10, 2023
概括
聚合物中的电荷不对称性显著影响液态-液态相隔动力学. 较大的不对称性会减缓粗化,而溶剂质量会对对称和不对称的混合物产生不同的影响.
科学领域:
- 聚合物科学 聚合物科学
- 软物质物理学 软物质物理学
- 物理化学 物理化学
背景情况:
- 混合相反电荷的大分子诱导液-液相分离.
- 这一过程形成了富含聚合物的协体阶段和富含聚合物的超体阶段.
- 了解这种相位分离的动态对于各种应用至关重要.
研究的目的:
- 调查聚合物中电荷不对称对液态-液态相分离的粗化动态的影响.
- 探索溶剂质量如何在对称和不对称的聚合物混合物中影响这些动态.
- 通过分析滴滴相互作用来阐明潜在的机制.
主要方法:
- 制备具有不同程度电荷不对称性的聚合物溶液.
- 使用显微镜观察和分析液-液相分离动态.
- 粗化动力学的定量测量,包括明显增长指数.
- 聚合物-聚合物和聚合物-溶剂相互作用的特征.
主要成果:
- 电荷不对称性显著减缓了同相的粗化动态.
- 表面增长指数偏离在中性系统中观察到的1/3的普遍值,并且随着电荷不对称的增加而减少.
- 降低溶剂质量在不对称混合物中加速粗化,但在对称混合物中减缓粗化.
- 对液滴融合的分析揭示了由电荷分布影响的独特相互作用潜力.
结论:
- 电荷不对称是一个关键参数,控制了宏分子合体形成的动力学.
- 电荷不对称性和溶剂质量之间的相互作用提供了一个可调节的途径来调节相位分离动态.
- 了解滴滴相互作用潜力,可以了解这些复杂的流体系统的基本机制.
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