在水溶液中具有相反电荷的多离子结合的驱动力:内热,内热,但非静电
Jingcheng Fu1, Joseph B Schlenoff1
1Department of Chemistry and Biochemistry, The Florida State University , Tallahassee, Florida 32306, United States.
Journal of the American Chemical Society
|January 16, 2016
概括
聚合物的驱动力不仅仅是静电. 受到特定离子配对影响的水扰动显著影响变化,自由能量主要由驱动.
科学领域:
- 聚合物科学
- 物理化学
- 解决方案化学
背景情况:
- 在溶液中具有相反电荷的聚合物协会通常归因于静电相互作用.
- 这些静电力包括性 (对子释放) 和性 (库伦引力) 组成部分.
- 连续静电学理论通常将小的外热/内热解释为库伦相互作用的证据.
研究的目的:
- 为了比较聚电解质协会的静电和特定离子配对机制.
- 调查多-多离子复合过程中变化的起源.
- 阐明对电离子和水结构在聚合物协会中的作用.
主要方法:
- 静电与特定离子配对模型的对比.
- 采用霍夫迈斯特的一系列用聚二甲基 (PDADMA) 制成的反.
- 使用拉曼散射来研究水的OH振动,并评估水的扰动.
主要成果:
- 发现度变化源于水扰动的变化,而不仅仅是库伦比引力.
- 拉曼光谱检测显示了水结构的变化与反的同一性相关.
- 复合的自由能量主要是不同度的.
结论:
- 涉及水结构变化的特定离子配对和离子交换机制对于理解多电解质协会至关重要.
- 传统的静电模型可能无法完全捕捉热力学驱动力.
- 在聚合物复合的能量学中,对抗体对水结构的特异性影响起着重要作用.
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