通过传统的方法,制备了两种对水和空气稳定的四烷基膦类离子液体.离子液体是:己基三丁基膦四氟化硼和己基三丁基膦双三氟甲基磺酸亚胺.在T=283.15-353.15 K温度范围内,测定了两个离子液体的密度、动力粘度及电导率.讨论了温度、阴离子结构对离子液体的性质的影响.结合文献报道的其它离子液体,讨论了该类离子液体性质随阳离子结构的变化规律,并与咪唑类离子液体的性质进行了比较.通过经验方程,利用密度数据计算了两个离子液体的重要热力学性质参数,例如:分子体积、标准摩尔熵及晶格能等.并将估算性质与传统的咪唑、吡啶类离子液体进行了对比.通过密度和电导率确定了离子液体的摩尔电导率.讨论了Vogel-Fulcher-Tamman (VFT)方程和Arrhenius方程对于粘度和电导率拟合的可行性,并估算了电导活化能及流动活化能.通过Walden规则,描述了密度、粘度及电导率之间的联系.有关研究对新型离子液体的合成及其工业化的应用具有十分重要意义.%Two air and water stable hydrophobic phosphonium ionic liquids (ILs),tributyl-hexylphosphonium tetrafluoroborate ([P4446][BF4]) and tributyl-hexylphosphonium bis(trifluoromethylsulfonyl)imide ([P4446][NTf2]),were prepared by the traditional method.Their basic physico-chemical properties of density,dynamic viscosity,and electrical conductivity were measured in the temperature range of 283.15-353.15 K.The effect of the temperature and structure of the anion on the thermodynamic properties were discussed.The properties arecompared with the cation structures changing of the phosphonium type ILs.The most important thermodynamic properties for their practical application,such as molecular volume,standard molar entropy,and lattice energy,were calculated from their density using empirical equations.The calculated values were compared with thoseof imdazolium and pyridinium type ILs.Molar electrical conductivity was determined from density and electricalconductivity.The applicability of the VogeI-Fulcher-Tamman (VFT) and Arrhenius equations to the fitting of thedynamic viscosity and electrical conductivity was validated.The activation of the electrical conductivity and dynamic viscosity were obtained from the final VFT equation.According to the Walden rule,the density,dynamic viscosity,and electrical conductivity were described by the Walden equation.The results are very important for academic studies as well as industrial applications of these ILs.
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