The sorption of toluene at 25 degreesC in different polyurethane foams was studied. The results revealed that the differences in the composition of the foams have only a small influence in the sorption capacity, indicating that the sorption is mainly controlled by dispersion forces. The sorption isotherms of benzene, toluene, ethylbenzene, cyclohexane, and methyl ethyl ketone (MEK) at 25, 30, and 35 degreesC were determined in a selected polyurethane foam. The three-suffix Margules equation and the Flory-Huggins equation were used to correlate the experimental data of the aromatic compounds at different temperatures. The prediction of the sorption isotherms of cyclohexane and MEK at different temperatures was attempted with the Flory-Huggins equation. The predicted sorption isotherms of cyclohexane were similar to those obtained by the interpolation with the Margules equation. However, for the MEK, the prediction is rather poor, due probably to the high dipole moment of this molecule. The validity of the estimations at low pressures was discussed by comparison of the predicted activity coefficients at infinite dilution, obtained by the two methods, with the ones obtained from the Henry's law.