Solubility of polystyrene with various molecular weights in subcritical 1,1,1,2-tetrafluoroethane: experiment and modified model

The solubility of polystyrene with molecular weight of 100 000 and 260 000 g mol −1 was measured at temperatures from 313 to 333 K and at pressures from 5.0 to 13.0 MPa in subcritical 1,1,1,2-tetrafluoroethane (R134a). The effects of pressure, temperature and molecular weight on the solubility of polystyrene were investigated. Meanwhile, the solubility of polystyrene was correlated using six density-based semi-empirical models (Chrastil, A-L, K-J, S-S, M-S-T and Bartle). The M-S-T model was used to verify the self-consistency of the experimental data, and the enthalpy values of polystyrene, including Δ H total , Δ H sub and Δ H sol , were estimated through the Chrastil and Bartle models. In addition, a modified M-S-T model was proposed through a detailed study of semi-empirical model formulas and verified by the solubility of polystyrene in subcritical R134a and 38 other solid solutes in supercritical carbon dioxide and subcritical R134a. © 2018 Society of Chemical Industry