Anomalous Diffusion of Vapors Through Solid Polymers. Part II: Anomalous Sorption
Sorption of vapors in polymer membranes in the vicinity of and below the glass transition temperatures do not follow the Fickian (classical) diffusion. the reasons have been attributed to the molecular relaxation which affects both diffusivities and solubilities. a time- and memory-dependent diffusion coefficient has been evaluated in Part I, in a form which is analogous to the treatment in the rheology of such materials. Together with a time-dependent solubility, the conservation equation for the sorption process has been solved. Two special cases are considered, where the relaxation times are short and where they are long. the results explain the anomalous behavior observed in the experiments.
P. Neogi, "Anomalous Diffusion of Vapors Through Solid Polymers. Part II: Anomalous Sorption," Wiley-Blackwell, Sep 1983.
Chemical and Biochemical Engineering
Keywords and Phrases
Diffusion - Thermodynamics; Mass Transfer; Membranes; Polymers; Solutions; Vapors
Article - Journal
© 1983 Wiley-Blackwell, All rights reserved.