Correlation and prediction of Henry constants for liquids and gases in five industrially important polymers using a CS-type correlation based on the van der Waals equation of state. Comparison with other predictive models

A simple two-parameter corresponding states-type method for the prediction of Henry constants of gases and liquid solvents in polymer solutions recently presented in the literature is thoroughly evaluated here and compared with the predictions of other models used for polymers. The corresponding states-type method is based on the van der Waals equation of state which has been recently extended to mixtures including polymers. Results are presented for systems containing five polymers in a variety of gases and nonpolar and polar liquid solutes. It is shown that agreement between experimental and calculated Henry constants is, in most cases, quite good and that the estimations with the new method compare favorably with the UNIFAC-FV and Entropic-FV activity coefficient models, the GC-Flory liquid-phase equation of state while they are somewhat better than the Group Contribution Lattice-Fluid (GCLF) equation of state. The proposed method is currently limited to five polymers but it is applicable to supercritical solvents, where the two activity coefficient models and the GC-Flory equation of state cannot be used.