Ether-functionalized ionic liquids (ILs) 1-(4-methoxybutyl)-3-methylimidazolium chloride ([COC₄mim][Cl]) and 1-(4-methoxybutyl)-3-methylimidazolium aspartic acid ([COC₄mim][Asp]) were successfully prepared. In terms of the standard addition method, the experimental values of the surface tension, density, and refractive index of these ether-functionalized ILs were obtained at 288.15–318.15 K. Using the Lorentz–Lorenz empirical equation, the values of the molar refraction and molar polarizability for [COC₄mim][Cl] and [COC₄mim][Asp] ILs were calculated. According to the definition of the polarity coefficient, the polarity of samples and other ILs was estimated. For the same anion, the polarity of the same series of ILs gradually reduced with increasing carbon chain length of ILs. For the same cation, the polarity of ILs was also influenced by anionic species. The prediction result of the polarity coefficient was in good agreement with δ_μ.

中文翻译：

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新型醚功能化离子液体的极性预测─[COC4mim][Cl]和[COC4mim][Asp]

醚官能化离子液体 (IL) 1-(4-甲氧基丁基)-3-甲基咪唑氯化物 ([COC ₄ mim][Cl]) 和 1-(4-甲氧基丁基)-3-甲基咪唑鎓天冬氨酸 ([COC ₄ mim] [Asp]) 已成功制备。就标准添加方法而言，这些醚官能化离子液体的表面张力、密度和折射率的实验值在 288.15-318.15 K 下获得。使用 Lorentz-Lorenz 经验方程，摩尔折射值和[COC ₄ mim][Cl] 和 [COC ₄的摩尔极化率计算了 mim][Asp] ILs。根据极性系数的定义，估计样本和其他ILs的极性。对于相同的阴离子，同一系列离子液体的极性随着离子液体碳链长度的增加而逐渐减小。对于相同的阳离子，离子液体的极性也受阴离子物质的影响。极性系数的预测结果与δ _μ吻合较好。