Vapour–liquid equilibrium of ternary aqueous polymer solutions containing polyethylene glycol and polyethylene glycol dimethyl ether at different temperatures

Water activities of ternary aqueous polymer solutions containing polyethylene glycol and polyethylene glycol dimethyl ether were determined experimentally using an improved isopiestic method at T=298.15, 308.15 and 318.15 K. The applicability of the modified Wilson model was tested for correlation of water activity of ternary polymer–polymer–solvent solutions studied in this work and others studied previously. The parameters determined in binary solutions were used in the calculation of water activity of ternary polymer solutions.

► We measured water activity data for polymer+polymer+H2O system.
► The isopiestic method is used at T=298.15, 308.15 and 318.15 K and the polymers are PEG and PEGDME.
► Water activities were fitted with the modified Wilson model.
► In determination of parameters temperature dependency was also considered.