Abstract The knowledge of the viscosity of ionic liquids is crucial for the design and development of industrial processes that involve these fluids, as well as for the theoretical study of this property. In this study, viscosities of four protic ionic liquids (PILs) consisting of ethanolamine as cation and formate, acetate, butyrate and hexanoate as anions, have been measured at the temperature range from 293.15 to 393.15 K, at atmospheric pressure. Viscosities of binary and ternary mixtures of these ionic liquids with water and ethanol at 293.15, 298.15 and 303.15 K have been also measured. PILs were found to be highly viscous fluids, except for 2-hydroxyethylammonium formate, and their viscosity is affected to a great extent by the presence of water and/or ethanol. The temperature dependency of the viscosity for pure ionic liquids is analyzed by means of the Vogel-Tammann-Fulcher equation, while for ionic liquid mixtures a modified Grunberg-Nissan equation is developed in this work. Satisfactory agreement between the experimental data and the model was obtained in all cases. Finally, the glass transition temperature of the PILs was measured.

中文翻译：

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纯质子离子液体及其与水和乙醇的二元和三元混合物的粘度

摘要 离子液体粘度的知识对于涉及这些流体的工业过程的设计和开发以及该特性的理论研究至关重要。在这项研究中，在 293.15 至 393.15 K 的温度范围内，在大气压下测量了四种质子离子液体 (PIL) 的粘度，其中包括乙醇胺作为阳离子和甲酸盐、乙酸盐、丁酸盐和己酸盐作为阴离子。还测量了这些离子液体与水和乙醇的二元和三元混合物在 293.15、298.15 和 303.15 K 下的粘度。发现 PIL 是高粘度流体，除了 2-羟乙基甲酸铵，它们的粘度在很大程度上受水和/或乙醇的影响。纯离子液体粘度的温度依赖性通过 Vogel-Tammann-Fulcher 方程进行分析，而对于离子液体混合物，本文开发了改进的 Grunberg-Nissan 方程。在所有情况下都获得了实验数据和模型之间令人满意的一致性。最后，测量 PIL 的玻璃化转变温度。