European Polymer Journal, Volume 60, 2014, Pages 49-57.
Ondřej Vopička, Alena Randová, Karel Friess.
Institute of Chemical Technology, Department of Physical Chemistry, Technická 5, Prague 6, 166 28, Czech Republic.
Abstract
Novel data on the sorption of vapours and liquids in cross-linked poly(dimethylsiloxane) (PDMS) elastomer at 25–40 °C are reported together with the accurate and original way of parameterising the sorption isotherms by using the GAB (Guggenheim, Anderson and De Boer) model of multilayer adsorption. The GAB model has been found to provide a comparable or better representation of sorption isotherms than the Flory–Huggins model with a concentration-dependent interaction parameter and better than the ENSIC (Engaged Species Induced Clustering) model. This comparison holds true for poor solvents of PDMS (water, methanol), mild solvents (acetone, methyl acetate, dimethyl carbonate) and good solvents (tert-butyl methyl ether, tert-amyl methyl ether, cyclopentyl methyl ether). The GAB model provided a noticeably good assessment of the sorption of liquids and highly saturated vapours, which makes the model applicable within the entire activity range.