Extensions of the SAFT model for complex association in the bulk and interface

In honor of the 25th anniversary of the SAFT equation of state, this paper presents a brief review of successes in modeling fluid mixtures with associating, polyatomic, and polar components using the SAFT equation of state. Challenges for the association term to predict monomer and dimer fractions in comparison with spectroscopic data are described. To address these challenges and challenges in patchy colloids, extensions to the associating term are reviewed that incorporate multiple bonding at association sites and cooperative association. Approximations in these extensions are validated through comparisons with molecular simulation results. Further, application of the density functional form of the theory to form micelles is briefly reviewed.