Experimental investigation and modeling of the density, refractive index, and dynamic viscosity of 1-Propyronitrile-3-Butylimidazolium Dicyanamide.

This work deals with the synthesis and characterization of ionic liquid 1-Propyronitrile-3-Butylimidazolium Dicyanamide [C 2 CNBIM][N(CN) 2 ], followed by the experimental investigations on the density, refractive index, and dynamic viscosity of 1-Propyronitrile-3-Butylimidazolium Dicyanamide ionic liquids (IL) within the temperature range of 293.15 K to 353.15 K. The results revealed that the density decreased from 1.1197 g/cm3 to 1.0940 g/cm3 with the rise in temperature due to the increase in volume as a result in an increase in the intermolecular distance. The refractive index was found to be reduced from 1.5195 to 1.5061 alongside temperature increments due to the compact groups of molecules being demolished following the increased intermolecular distance. The dynamic viscosity found to be reduced from 276.26 mPa·s to 15.896 mPa·s with an increase in temperature because of weakened van der Walls forces compared to the hydrogen bonding with rising temperature and kinetic energies. Furthermore, ten different generalised models were applied for density prediction, exhibiting the minimum possible standard deviation of 0.0089. To improve the prediction ability, group contribution method-based models were developed for the density, refractive index, and dynamic viscosity prediction, resulting in the optimum values of standard deviation, average absolute relative deviation (AARD%), and correlation coefficient of 0.0081, 0.45%, and 0.9145, respectively. The developed models demonstrated a good agreement with the experimental data and previously reported models. Therefore, the proposed models are believed to be adequately precise for engineering calculations. Unlabelled Image • An ionic liquid [C 2 CNBIM][N(CN) 2 ] synthesised and characterized • Density, refractive index, and dynamic viscosity measured experimentally • Negative influence of temperature on physical properties was observed. • Proposed models are believed to be precise enough for engineering calculations. [ABSTRACT FROM AUTHOR]