1,2-丙二醇+丁醇/戊醇/己醇二元系的过量体积和黏度

Excess Molar Volumes and Viscosities of Binary Mixtures Composed of 1,2-Propanediol with Butanol, Pentanol or Hexanol

常压下测定了1,2-丙二醇分别与丁醇、戊醇和己醇组成的二元系在293.15～318.15 K下的密度和黏度,建立了混合液密度和黏度随温度和组成变化的方程。计算了过量摩尔体积VE,黏度偏差Δη和过量流动活化自由能ΔG＊E。结果表明,三个二元系的过量摩尔体积在全浓度范围内均为正值,随温度升高,偏差增大,但发生最大偏差时的溶液组成不同;过量摩尔体积值按丁醇-戊醇-己醇顺序逐渐增大;黏度偏差和过量流动活化自由能三个体系显示了相同的变化关系,均为负值,且都随温度降低而偏差增大。利用Redlich-Kister方程对过量性质进行了关联。分析和讨论了分子间相互作用。

The densities and viscosities of binary mixtures consisting of butanol, pentanol or hexanol with 1,2-propanediol（12PD） were measured using pycnometer and Ubbelohde viscometer at 293.15~318.15 K under atmospheric pressure. The density and viscosity data of the binary mixtures were fitted as functions of composition and temperature. Excess molar volumes（VE）, viscosity deviations（Δη） and excess Gibbs energy of activation of viscous flow（ΔG＊E） were calculated from the experimental data. The results show that the excess molar volumes are positive over the whole mole fraction range in the temperature range studied for all of the binary mixtures, and the deviation increases as temperature increases. However, the largest deviation varies in different solution compositions. The excess molar volume value increases following an order of butanol-pentanol – hexanol. Both Δη and ΔG＊E are negative over the whole mole fraction range in the temperature range studied for all of the binary mixtures, and the deviation increases as temperature decreases. All of the excess properties are correlated by the Redlich-Kister equation and the molecular interactions are analyzed.