Structure and dynamics of water in mixed solutions including laponite and PEO.
Structure and dynamics of water in mixed solutions including laponite and PEO.
复制标题
DOI：
10.1063/1.3533233
复制
发表时间：
2011-01
期刊：
影响因子：
--
通讯作者：
S. Morikubo;Yurina Sekine;T. Ikeda-Fukazawa
中科院分区：
文献类型：
--
作者：
S. Morikubo;Yurina Sekine;T. Ikeda-Fukazawa
为了研究锂皂石粘土颗粒和聚氧化乙烯（PEO）混合溶液中水的结构和动力学，我们在283-313 K温度范围内测量了混合溶液的拉曼光谱。结果表明，混合溶液中O-H伸缩振动模的振动能与水含量和温度有关。O-H伸缩模的能量移动归因于水结构的变化。通过将体相水的结构模型应用于O-H伸缩区的光谱，分析了水在溶液中的局域结构。结果表明，随着水含量的降低，溶液中氢键的形成几率降低。锂皂石和PEO具有破坏水分子之间氢键的网络结构的作用。此外，发现合成锂皂石和PEO导致周围水的氢键强度增加，尽管氢键强度以水-合成锂皂石<水-水<水-PEO的顺序增加。结果表明，锂皂石-PEO混合溶液中的水具有较弱的网络结构，与本体水相比具有较强的氢键。
To investigate the structure and dynamics of water in mixed solutions including laponite clay particles and poly(ethylene oxide) (PEO), we measured the Raman spectra of the mixed solutions in the temperature range 283-313 K. The results show that the vibrational energies of the O-H stretching modes in the mixed solutions depend on the water content and temperature. The energy shifts of the O-H stretching modes are attributed to changes in the water structure. By applying a structural model of bulk water to the spectra in the O-H stretching region, the local structures of water in the solutions were analyzed. The result shows that the formation probability of hydrogen bonds in the solutions decreases as the water content decreases. Laponite and PEO have effects to disrupt the network structure of hydrogen bonds between water molecules. Further, it was found that laponite and PEO cause increase in the strength of hydrogen bonds of surrounding water,although the strength of the hydrogen bonds increases with the order water-laponite < water-water < water-PEO. It is concluded that water in laponite-PEO mixed solutions has a less-networked structure with strong hydrogen bonds compared with bulk water.