As a part of the optimization of a recently developed process through which polyurethanes are produced using carbon dioxide (CO2) as a raw material, the solubilities of CO2 and of propylene oxide (PO) in polyether polycarbonate polyols (PPP), an intermediary in the production of polyurethanes, were measured at pressures up to 10 MPa and 1 MPa, respectively, at temperatures between 363 K and 413 K. Experiments were performed using the synthetic-isothermal method. The influence of propylene carbonate, also present in the process, was investigated by studying the solubilities of CO2 and PO in different mixtures of PPP and propylene carbonate at 383 K. Finally, the solubility of CO2 in a polyether, one of the reactants in the process, was also measured at 383 K. The experimental results were modeled with the Soave-Redlich-Kwong equation of state with the Peneloux-Rauzy volume translation and Mathias-Klotz-Prausnitz mixing rules. (c) 2012 Elsevier B.V. All rights reserved.