Hole-Filling Theory of Anomalous Diffusion in Glassy Polymers. Effects of Microvoids
Non-Fickian diffusion is often observed at low concentrations and without any obvious irreversible changes. This contradicts some of the predictions of the existing theories, which in general work quite well. For these cases, it is suggested that the filling of microvoids give rise to such effects. the effective diffusivity and a memory-dependent source/sink term are obtained for describing the overall transport in heterogeneous media under local volume averaging. Some comparisons with experiments are shown. This mechanism is confined to low concentrations and supplements the existing theories which are effective at higher concentrations.
P. Neogi, "Hole-Filling Theory of Anomalous Diffusion in Glassy Polymers. Effects of Microvoids," Wiley-Blackwell, May 1993.
The definitive version is available at http://dx.doi.org/10.1002/polb.1993.090310610
Chemical and Biochemical Engineering
Keywords and Phrases
Anomalous Diffusion; Diffusion in Solids; Hole Filling Theory; Mass Transfer; Mathematical Models; Memory Dependent Source/Sink Term; Microvoids; Non Fickian Diffusion; Polymeric Glass; Structure (Composition)
Article - Journal
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