盐对充电大分子溶液中的普通-非凡过渡的影响
Di Jia1, Murugappan Muthukumar1
1Department of Polymer Science and Engineering , University of Massachusetts , Amherst , Massachusetts 01003 , United States.
Journal of the American Chemical Society
|March 22, 2019
概括
高度的盐在充电的大分子溶液中显示出新的动态. 聚合物分子重量显著影响这些转变,挑战现有的普通-非凡行为理论.
科学领域:
- 物理化学
- 聚合物科学
- 软物质物理学
背景情况:
- 溶液中的带电大分子表现出由盐度影响的复杂动态.
- "普通-非凡"过渡描述了不同盐和聚合物度的宏分子行为变化.
- 之前的模型集中在聚合物与盐度 (Cp/Cs) 的比率上,用于预测过渡.
研究的目的:
- 研究高度对充电大分子溶液中"普通-非凡"过渡的作用.
- 探索聚合物分子重量 (Mw) 对多电解质溶液的集体动态的影响.
- 开发一个理论框架来解释盐多电解质系统的观察动态.
主要方法:
- 测量扩散系数的动态光散射 (DLS) 技术.
- 聚合物度 (Cp),盐度 (Cs) 和聚合物分子量 (Mw) 的系统变化.
- 对水性聚硫酸盐和化溶液进行实验.
主要成果:
- 除了以前已知的"快速"和"缓慢"模式外,还观察到了新的"快速"放松模式.
- 证明Mw是多电解质溶液动态的一个关键因素,而不仅仅是Cp/Cs比率.
- 随着Mw的下降,从三到两到一个放松模式的动态过渡的识别.
结论:
- 一个新的快速模式的出现和观察到的动态转换挑战建立了"普通-非凡"的转换理论.
- 一个新的理论模型对链, counterions 和 co-ions 的合放松进行了定性解释.
- 这项工作为精确描述生物和技术相关的盐溶液中的带电大分子动力学提供了基础.
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