Our work in this area involves both "conventional" and "unusual" phenomena associated with the selective layer and support structure of membranes. Most changes in membrane performance due to temperature, pressure and feed composition are understandable in terms of conventional equilibrium thermodynamic and Fickian transport phenomena. Changes in separation efficiency due to thermal or reversible swelling-induced activation of motions responsible for diffusion are important examples of this fundamental area of our work.

Less conventional, but hightly fascinating effects due to non-equilibrium thermodynamic and non-Fickian transport phenomena are also topics of our investigation. Long-lived conditioning effects due to to exposure of membranes to elevated concentrations of certain penetrants typify such non-equilibrium phenomna. Protracted aging of glassy polymers, carbons and inorganic membranes following formation or conditioning treatments also are examples of these unusual effects. In many cases, these effects seem to defy logic -- until one realizes that an expanded set of rules governs these out-of-equilibrium materials. This is a ground-breaking area of both fundamental and practical importance.

• Membrane and barrier materials
• Formation and application of polymeric, ceramic, and carbon membranes