Tochigi, K; Matsumoto, T; Kurihara, K; Ochi, K
For the Sako-Wu-Prausnitz (SWP) cubic equation of state, parameters were determined for 10 polymers [low-density polyethylene, poly(ε-caprolactone), poly(epichlorohydrin), poly(methyl methacrylate), poly(o-methylstyrene), polypropylene, poly(isobutylene), polystyrene, poly(vinyl acetate), and poly(vinyl chloride)] using literature PVT data ranging from the ambient conditions up to 470 K and 200 MPa. The correlated results of relative volume agreed with average deviations of 0.06% and were better than those of the original SWP equation (Sako et al. J. Appl. Polym. Sci. 1989, 38, 1839-1858). When the SWP equation is combined with the GE mixing rule and the ASOG-FV group contribution method, the solvent activities for polymer solutions composed of 4 polymers and 13 solvents (benzene, toluene, cyclohexane, acetone, butyl acetate, etc.) could be predicted. The prediction accuracy was somewhat better than that of PRASOG-FV although the accuracy of the PVT calculation for polymers did not almost influence the prediction accuracy of the vapor-liquid equilibria for binary solutions at normal pressure.