制备了离子液体1-甲基咪唑醋酸盐([Mim]Ac),1,3-二甲基咪唑醋酸盐([Mmim]Ac)和1-乙基-3-甲基咪唑醋酸盐([Emim]Ac),分别测定了它们在293.15-338.14 K间的密度、电导率和绝对粘度,计算了相应的摩尔电导率和运动粘度.用最小二乘法分别拟合建立了密度、电导率、摩尔电导率、绝对粘度和运动粘度与温度的函数关系.讨论了咪唑环3位氮原子上烷基链长对以上咪唑醋酸盐五种物理化学性质的影响.在293.15 K测定了[Mim]Ac{或[Mmim]Ac,[Emim]Ac}(1)-H2O(或EtOH) (2)二元溶液在全浓度范围内的电导率,计算了对应的咪唑醋酸盐的摩尔电导率.发现无论是水溶液还是乙醇溶液,溶液的电导率和咪唑醋酸盐的摩尔电导率都随着浓度的增加先增大而后减小.同一浓度下,咪唑环3位氮原子上烷基链长增加,相应的溶液电导率和摩尔电导率下降.且水溶液的电导率和摩尔电导率远大于乙醇溶液的.%The ionic liquids 1-methylimidazolium acetate ([MimJAc), 1,3-dimethylimidazolium acetate ([MmimJAc), and 1-ethyl-3-methylimidazolium acetate ([EmimJAc) were prepared and their densities, conductivities, and absolute viscosities were measured at temperatures ranging from 293.15 to 338.14 K. Their corresponding molar conductivities and kinematic viscosities were also calculated. The dependence of densities, conductivities, molar conductivities, absolute viscosities, and kinematic viscosities on temperature were obtained using the least-squares method. The influence of the alkyl chains at the 3-position N atom of the imidazole ring on the above five physicochemical properties of these imidazolium acetates were discussed. The conductivities of binary solutions of [Mim]Ac {or [MmimJAc or [EmimJAc} (1)-H2O (or EtOH) (2) were measured for a full set of mole fractions and the corresponding molar conductivities of the three imidazolium acetates in the six binary solutions were also calculated. In water and ethanol solutions we found that the conductivities and the molar conductivities increased initially and then decreased with an increase in the mole fraction of the imidazolium acetates. At the same concentration a longer alkyl chain at the 3-position of the imidazole ring resulted in higher conductivity and molar conductivity for the imidazolium acetates. Furthermore, the conductivities and molar conductivities of the aqueous solutions are always far higher than those of ethanol solutions.
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