The solubility of styrene from polystyrene in supercritical carbon dio
xide is measured at 323 K, 333 K, and 343K in the pressure range from
12 to 28 MPa. Based on the association concept and the theory of dense
gas sorption in polymers, a displacement and association mechanism on
supercritical fluid extraction of the monomer from the polymer is pro
posed. And, a novel mathematical model for correlating the solubility
data obtained from the experiments is also proposed in the paper.