Abstract This work reports thermophysical properties measurements of binary mixtures of N,N-dimethylacteamide with 1-pentanol and 2-pentanol. Density, ρ, speed of sound, u, refractive index, nD, and kinematic viscosity,ν, were measured over the whole composition range at the temperatures (283.15, 298.15 and 313.15) K and at atmospheric pressure p = 0.1 MPa. Experimental data were used to calculate the following properties: excess molar volume, VE, excess isentropic compressibility, κ S E , refractive index deviation, ΔnD, and viscosity deviation, Δη. These properties were correlated with mole fraction or volume fraction using the Redlich-Kister equation. Excess molar volumes were positive for both mixtures although there are some slight negative VE values for the system containing 1-pentanol at lower temperatures and at lower mole fractions. Refractive index deviation behaviour against composition for (N,N-dimethylacetamide + 1-pentanol) was sigmoidal at lower temperatures and negative at T = 313.15 K, on the other hand ΔnD values are negative for the mixture with 2-pentanol. Excess isentropic compressibilities and viscosity deviations were negative for the two systems. The results obtained were interpreted based on both structural and energetic effects. These results were further compared with our previous results for mixtures containing N,N-dimethylacetamide and several n-alkanols or 2-alkanols in order to understand both the influence of the hydrocarbon chain length and the hydroxyl group position.

中文翻译：

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N,N-二甲基乙酰胺与正链烷醇或2-链烷醇的热物理性质取决于烃链长度和羟基位置

摘要 这项工作报告了 N,N-二甲基乙酰胺与 1-戊醇和 2-戊醇的二元混合物的热物理性质测量。在温度 (283.15、298.15 和 313.15) K 和大气压力 p = 0.1 MPa 下，在整个组成范围内测量了密度 ρ、声速 u、折射率 nD 和运动粘度 ν。实验数据用于计算以下特性：过量摩尔体积 VE、过量等熵压缩率 κ SE 、折射率偏差 ΔnD 和粘度偏差 Δη。使用 Redlich-Kister 方程将这些特性与摩尔分数或体积分数相关联。尽管在较低温度和较低摩尔分数下含有 1-戊醇的系统有一些轻微的负 VE 值，但两种混合物的过量摩尔体积都是正的。(N,N-二甲基乙酰胺 + 1-戊醇) 的折射率偏差行为在较低温度下为 sigmoidal，在 T = 313.15 K 时为负值，另一方面，对于与 2-戊醇的混合物，ΔnD 值是负值。两个系统的等熵压缩性和粘度偏差过大都是负的。基于结构和能量效应对获得的结果进行了解释。这些结果与我们之前对含有 N,N-二甲基乙酰胺和几种正链烷醇或 2-链烷醇的混合物的结果进行了进一步比较，以了解烃链长度和羟基位置的影响。另一方面，对于与 2-戊醇的混合物，ΔnD 值为负。两个系统的等熵压缩性和粘度偏差过大都是负的。基于结构和能量效应对获得的结果进行了解释。这些结果与我们之前对含有 N,N-二甲基乙酰胺和几种正链烷醇或 2-链烷醇的混合物的结果进行了进一步比较，以了解烃链长度和羟基位置的影响。另一方面，对于与 2-戊醇的混合物，ΔnD 值为负。两个系统的等熵压缩性和粘度偏差过大都是负的。获得的结果基于结构和能量效应进行解释。这些结果与我们之前对含有 N,N-二甲基乙酰胺和几种正链烷醇或 2-链烷醇的混合物的结果进行了进一步比较，以了解烃链长度和羟基位置的影响。