Proton Dissociation of Sulfonated Polysulfones: Influence of Molecular Structure and Conformation
Proton Dissociation of Sulfonated Polysulfones: Influence of Molecular Structure and Conformation
复制标题
磺化聚砜的质子解离：分子结构和构象的影响
DOI：
10.1021/ma502550f
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发表时间：
2015
期刊：
影响因子：
5.5
通讯作者：
J. Maier
中科院分区：
文献类型：
--
作者：
A. Wohlfarth;Jens Smiatek;K. Kreuer;S. Takamuku;P. Jannasch;J. Maier
通过结合电泳核磁共振、脉冲磁场梯度核磁共振和离子基团浓度在解离不完全范围内的单体和聚合物样品的电导率测量，研究了质子导电性磺化聚砜的反离子凝聚行为（IEC = 4.55-7.04毫当量g-1）。在这种情况下，反离子凝聚被证明严重依赖于分子结构的细节，并且所有原子分子动力学（MD）模拟揭示了明确定义的离子聚集体（例如，三重离子）。相应的全球最低的自由能建议是一个微妙的平衡的能量参与构象变化，形成离子聚集体，和溶剂化的结果。这超越了曼宁的反离子凝聚理论，并对许多电化学应用（如燃料电池和电池）所需的高离子电导率膜的开发具有重要意义。
The counterion condensation behavior of proton conducting sulfonated polysulfones has been investigated by combining electrophoretic NMR, pulsed magnetic field gradient NMR, and conductivity measurements on monomeric and polymeric samples with concentrations of ionic groups in the range where dissociation is not complete (IEC = 4.55–7.04 mequiv g–1). In this regime, counterion condensation is shown to critically depend on details of the molecular structure, and all atom molecular dynamics (MD) simulations reveal the formation of well-defined ionic aggregates (e.g., triple ions). The corresponding global minima of the free energy are suggested to be the result of a delicate balance of the energetics involved in conformational changes, formation of ionic aggregates, and solvation. This goes beyond Manning’s counterion condensation theory and has important implications for the development of membranes with high ionic conductivity as needed for many electrochemical applications such as fuel cells and batteries.
影响因子：
2.9
作者：
Wang, Junmei;Wang, Wei;Case, David A.
通讯作者：
Case, David A.