聚氧化乙烯(PEO)在离子液中的第二维里系数和有效相互作用参数

The Second Virial Coefficient and the Effective Interaction Parameter for Poly(Ethylene Oxide)(PEO) in Ionic Liquids

应用分子理论研究聚氧化乙烯(PEO)在离子液体中的第二维里系数和有效相互作用参数,理论模型考虑了PEO在离子液体中的3种类型(Ⅰ型、Ⅱ型和Ⅲ型)的氢键作用.计算了可观察的第二维里系数A_2和有效相互作用参数χ_(eff).研究发现,PEO在离子液中的3种类型的氢键对第二维里系数A_2、有效相互作用参数χ_(eff)有重要影响,由于氢键效应,随着温度的升高第二维里系数减小,有效相互作用参数增加.理论结果可以深入理解PEO在离子液体中的相行为,根据计算结果可以推断,PEO在离子液体中的相行为,在很大程度上将会取决于氢键作用.

We use molecular theory to explore second virial coefficient A2 and effective interaction parameter Xe, for PEO in ionic liquids. Our theory model takes into consideration three types （type I, type 11 and type lU） of hy- drogen bonds （H-bonds） for PEO in ionic liquids solution. We found that the temperature dependence of the A2 and Xeff are influenced by type I, type II and type HI hydrogen bonds. The A2 decreases and Xee increases with an in- crease of temperature due to disruption of type I and type II hydrogen bonds. This leads to the decrease of solubility of PEO with an increase of temperature. According our calculating results, we expect that phase transition of poly （ethylene oxide） in an ionic liquid will be attributed to the effects of hydrogen bonding.