PC-SAFT-based entropy scaling framework for modelling liquid transport properties of polar and associating organic fluids

To address the limited availability of experimental data and the insufficient accuracy of conventional methods for correlating the liquid viscosity and thermal conductivity of alcohols, esters, and acids, this work combines the perturbed-chain statistical associating fluid theory (PC-SAFT) equation of state (EoS) with residual entropy scaling (RES) to adopt a unified modeling procedure and correlation form. Density and residual entropy from PC‑SAFT are used as thermodynamic inputs for transport property modelling. The model was applied to 12 representative organic fluids, including nine alcohols, two esters, and one carboxylic acid. The results show that the relative deviations of liquid density calculated in this work by PC‑SAFT are generally within ±1%. Within a deviation range of ±5%, the proposed expression model achieves a data coverage of over 96.5% for calculated viscosity values and over 98.7% for calculated thermal conductivity values. These results indicate that the combined PC-SAFT–RES framework provides an accurate and efficient approach for correlating the liquid transport properties of polar and associating organic fluids.