Physically insightful modeling of non-Fickian kinetic regimes encountered in fundamental studies of isothermal sorption of swelling agents in polymeric media

► Unique feature of this review: all possible causes of isothermal non-Fickian behavior are included. ► Review of highlights of mainstream modeling of non-Fickian kinetics in terms of underlying physics. ► Modeling patterns of kinetic behavior rather than isolated kinetic curves is shown to be essential. ► Demonstration of common causes of non-Fickian sorption and mechanical viscoelastic behavior. ► The applicability of Hansen's alternative modeling approach appears to be much more restricted.