Vapor–liquid equilibria in dendrimer and hyperbranched polymer solutions: experimental data and modeling using UNIFAC-FV

This work evaluates the potential of the group contribution method universal functional activity coefficients-free-volume (UNIFAC-FV) to predict vapor–liquid equilibria (VLE) in dendrimer-solvent and hyperbranched polymer-solvent systems. The VLE of hydroxyl-functional dendritic polymers (polyethers, polyesters, polyamidoamine), dissolved in polar solvents (ethanol and/or water) are studied both experimentally and theoretically. A new approach is suggested to account for the contribution of selected types of polymer structural units (i.e. linear, dendritic and terminal units) to the solvent residual activity. The results of calculations are in a good agreement with experiment. Further on the validity of recommended UNIFAC-FV parameters from literature for dendritic polymer solutions is discussed. In general, it has been shown that the UNIFAC-FV model combined with a consideration of molecular architecture of the dissolved dendritic polymers reflects the measured VLE data. These results encourage to draw the hypothesis that the VLE of other dendritic polymer solutions can also be well predicted following the issues described in this article.