Phase equilibria of polymer solutions: modified perturbed hard-sphere-chain equation-of-state

We modified the perturbed hard-sphere-chain (PHSC) equation-of-state by int roducing Chapman's equation into the bonding term of the reference equation . The proposed model successfully predicts the vapor/liquid equilibria (VLE ) of pure fluids with three characteristic parameters obtained for each sub stance. We also extended the modified PHSC equation-of-state to describe th e liquid/liquid equilibria (LLE) of polymer solutions. Characteristic param eters obtained from the pure substances were directly used to predict the L LE of polymer solutions. The calculated coexistence curves using the propos ed model agree remarkably well with the experimental data. (C) 1999 Elsevie r Science Ltd. All rights reserved.