Viscosities were measured for the ternary systems Y（NO3）3＋La（NO3）3＋H2O, La（NO3）3＋Ce（NO3）3＋H2O, and La（NO3）3＋Nd（NO3）3＋ H2O and their binary subsystems Y（NO3）3＋H2O, La（NO3）3＋H2O, Ce（NO3）3＋H2O, and Nd（NO3）3＋H2O at 293.15, 298.15 and 308.15 K. The results were used to test the applicability of simple equations for the viscosity of the mixed solutions. The predictions agreed well with measured values, implying that the viscosities of the examined electrolyte solutions could be related to those of their constituent binary solutions using these simple equations.
The simple equations for prediction of the density and viscosity of mixed electrolyte solutions were extended to the related properties of mixed ionic liquid solutions. The density and viscosity were measured for ternary solutions [C2q]Br（N-ethylquinolinium bromide）＋[C4q]Br （N-butylquinolinium bromide）＋H2O, [C2q]Br＋[C6q]Br（N-hexylquinolinium bromide）＋H2O, and [C4q]Br＋[C6q]Br＋H2O and their binary subsystems [C2q]Br＋H2O, [C4q]Br＋H2O, and [C6q]Br＋H2O at 15, 20 and 25 °C, respectively. The results were used to test the predictability of the extended equations. The comparison results show that these simple equations can be used to predict the density and viscosity of the mixed ionic liquid solutions from the properties of their binary subsystems of equal ionic strength.
The transport properties of ionic liquids(ILs) are crucial properties in view of their applications in electrochemical devices. One of the most important advantages of ILs is that their chemical–physical properties and consequently their bulk performances can be well tuned by optimizing the chemical structures of their ions. This will require elucidating the structural features of the ions that fundamentally determine the characteristics of the nanostructures and the viscosities of ILs. Here we showed for the first time that the "rigidity", the order,and the compactness of the three-dimensional ionic networks generated by the anions and the cation head groups determine the formation and the sizes of the nanostructures in the apolar domains of ILs. We also found that the properties of ionic networks are governed by the conformational flexibility and the symmetry of the anion and/or the cation head group. The thermal stability of the nanostructures of ILs was shown to be controlled by the sensitivity of the conformational equilibrium of the anion to the change of temperature. We showed that the viscosity of ILs is strongly related to the symmetry and the flexibility of the constitute ions rather than to the size of the nanostructures of ILs. Therefore, the characteristics of the nanostructures and the viscosities of ILs, especially the thermal stability of the nanostructures, can be fine-tuned by tailoring the symmetry and the conformational flexibility of the anion.
The densities, conductivities, and viscosities were measured for ternary solutions of N-hexyl,methylpyrrolidinium bromide([PP1,6]Br)- N-butyl,methylpyrrolidinium bromide([PP1,4]Br)-H2 O and its binary subsystems [PP1,6]Br-H2 O and [PP1,4]Br-H2 O at(298.15, 303.15, 308.15, and 313.15) K, respectively. The results were used to test the predictability of the simple equations established for the prediction of density, conductivity,and viscosity of the mixed electrolyte solutions. The results show that the examined simple equations can offer good predictions for density, conductivity, and viscosity of the mixed ionic liquid solutions in terms of the corresponding properties of its binary subsystems of equal ionic strength.
