Temperature dependence and energetics of the equilibrium sorption of water vapor in glassy polyacrylonitrile

Equilibrium sorption isotherms for water vapor in commercial polyacrylonitrile film are presented. The data are discussed in terms of hte dual‐mode sorption model at low vapor activities with cluster formation occuring at higher activities. The film samples were treated by a two‐stage extraction process to remove a tenaciously held solvent present from the manufacturing process. Extraction of the residual had a minor effect on the equilibrium sorption of water in the film. The temperature dependence of the various sorption parameters is presented and discussed in detailed.