Diffusion, permeation, and sorption equilibrium coefficients were determined for benzene, substituted benzenes, and bis(2-methoxyethyl) ether into tetrafluoroethylene-propylene copolymeric sheets in the temperature range from 298.15 to 343.15 K. From a temperature dependence of the transport coefficients, the activation parameters have been estimated. It is observed that the values of the transport coefficients and the derived parameters depend on the nature of penetrant molecules rather than their sizes.