在多电解质多层和复合体中,水化对协会的贡献:可视化疏水性.
Joseph B Schlenoff1, Amir H Rmaile, Claudiu B Bucur
1Department of Chemistry and Biochemistry, The Florida State University, Tallahassee, Florida 32306, USA. schlen@chem.fsu.edu
Journal of the American Chemical Society
|September 19, 2008
概括
聚电解质复合物水和离子兴奋剂效率由盐类型和聚合物化学控制. 较少的水合离子导致这些薄膜中更有效的兴奋剂.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 物理化学 物理化学
背景情况:
- 聚电解质复合物是通过相反电荷的聚合物之间的静电相互作用形成的.
- 多层组装是一种常见的技术,用于制造具有受控结构的薄膜.
- 了解离子兴奋剂和水化对于定制材料特性至关重要.
研究的目的:
- 调查盐类型,聚合物化学和多电解质复合物多层的水化和离子兴奋剂之间的关系.
- 阐明离子兴奋剂和多电解质协会背后的驱动力.
- 为描述多电解质结合强度建立一个通用参数.
主要方法:
- 使用多层化方法制造聚电解质复合薄膜.
- 在现场监测多层组件和使用减弱总内部反射率FTIR (ATR-FTIR) 的水合.
- 系统地改变盐类型和多电解质组合,以研究兴奋剂效率和水合水平.
主要成果:
- 盐类型显著影响了多电解质复合物多层的积累和离子兴奋剂.
- 通过ATR-FTIR精确测量多层的内部水分,取决于聚合物和盐离子的同一性.
- 兴奋剂的效率与水合相反相关:水合较少的离子是更有效的兴奋剂.
- 一个单一的通用参数描述了多电解质结合强度,与释放的水分子成比例.
结论:
- 在聚电解质复合体中,离子兴奋剂受水效应的控制,较少的水离子促进了更高的兴奋剂效率.
- 兴奋剂的驱动力可以通过考虑离子配对期间释放的水分子来合理化.
- 可以调节多层内的水化,提供一种控制材料性质的途径.
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