Experimental data for density, viscosity, refractive index and surface tension are reported, for the first time, in the temperature range between 288.15 and 353.15 K and at atmospheric pressure for two protic ionic liquids, namely 2-(dimethylamino)-N,N-dimethylethan-1-ammonium acetate, [N11{2(N11)}H][CH3CO2], and N-ethyl-N,N-dimethylammonium phenylacetate, [N112H][C7H7CO2]. The effect of the anion’s aromaticity and the cation’s aliphatic tails on the studied properties is discussed. Additional derived properties, such as isobaric thermal expansion coefficient, surface entropy and enthalpy and critical temperature, were estimated.

中文翻译：

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两种铵基质子离子液体的热物理性质

首次报道了在 288.15 和 353.15 K 之间的温度范围和大气压下两种质子离子液体即 2-(二甲氨基)-N,N- 的密度、粘度、折射率和表面张力的实验数据二甲基乙-1-乙酸铵，[N11{2(N11)}H][CH3CO2]，和 N-乙基-N,N-二甲基苯乙酸铵，[N112H][C7H7CO2]。讨论了阴离子的芳香性和阳离子的脂肪族尾巴对研究性质的影响。估计了其他衍生特性，例如等压热膨胀系数、表面熵和焓以及临界温度。