An analysis of the molecular transport of organic liquids into fluoroelastomer membranes containing varying amounts of carbon black has been undertaken by the sorption-desorption gravimetric method. The variation in carbon black loading and temperature showed a significant effect on their transport characteristics. Diffusion coefficients were calculated from Fick＇s equation. Experimental sorption-desorption results were analyzed in terms of concentration profiles obtained from a solution of Fick＇s equation as well as by a numerical method based on the finite difference technique. Arrhenius activation parameters were estimated from the temperature-dependent diffusion and permeation data. The results of this study are discussed in terms of polymer-solvent interactions.