Measurement and calculation of liquid-liquid equilibria of binary aqueous polymer solutions

The liquid-liquid equilibria (LLE) of aqueous solutions containing random c opolymers of ethylene oxide (EO) and propylene oxide (PO) with two differen t molecular weights were measured. The modified non-random two-liquid (NRTL ) model was used to calculate the phase behaviour of water-polymer systems with various molar ratios of EO to PO. Good agreement was obtained with the experimental data. The results show that the molecular weight and the mola r ratio of EO to PO of the polymer can strongly influence the phase behavio ur of H2O-EOPO systems. (C) 2000 Published by Elsevier Science S.A.