Phase behavior of poly(1,1-dihydroperfluorooctylacrylate) in supercritical carbon dioxide

Liquid–fluid phase equilibria data are reported for the poly(1,1-dihydroperfluorooctylacrylate) (poly(FOA))–CO2 system at sub- and supercritical fluid conditions and modeled with the statistical associated fluid theory (SAFT). Lower critical solution temperature (LCST) phase behavior is observed with a critical concentration between 1.0 and 2.0 wt.% poly(FOA). The high solubility of poly(FOA) is consistent with its low cohesive energy density and the weak van der Waals forces of CO2. To aid this analysis, pressure–volume–temperature (PVT) data are reported for pure poly(FOA) and correlated with lattice-fluid and SAFT theory.