Molecular transport of ketones and nitriles into commercial fluoroelastomeric membranes

The molecular transport of ketones such as acetone, ethyl methyl ketone, methyl isobutyl ketone, cyclohexanone and acetophenone, and nitriles such as acrylonitrile and acetonitrile, through Fluorel 3M membranes (FC-2177 D) was carried out in the temperature range of 30-50°C using the sorption gravimetric method. With the sorption data, the concentration-independent diffusion coefficients were calculated from Fick's diffusion equation. The liquid concentration profiles were also calculated from the analytical solution of Fick's diffusion equation with the appropriate initial and boundary conditions, and these were presented as a function of penetration depth of molecular migration and time of immersion. Because of the linearly increasing trend of the diffusion coefficients with temperature, efforts were made to estimate the Arrhenius parameters. Experimental values and the computed quantities were used to determine the membrane solvent interactions and to propose suitable applications in various situations. None of the solvents showed any degradative effects on the polymer membrane.