Viscoelastic deformation of sulfonated polymeric cation-exchange membranes exposed to a pressure gradient

Experimental determination of the streaming potential across cation-exchange membranes with different morphologies

“…This decrease may be related to nonlinear volume flows observed for short times. This effect is relatively larger at low pressure and it has been related to some mechanical relaxation or strain of the membrane whenever pressure is applied, with a short time scale [24,25]. Accordingly, the effect should be larger for membranes with higher hydraulic permeability, which are in agreement with the results found as shown later.…”

“…This membrane is a noncrosslinked membrane, whereas the other membranes are either cross-linked or reinforced. Previous studies reported the physical deformation of some polymeric membranes caused by the application of a hydrostatic pressure difference across them [25]. Results show differences depending on the membrane structure, thus, cross-linked membranes are less susceptible to be deformed due to their rigid structures, in contrast, non-crosslinked membranes, such as NF115, showed significant plastics deformations.…”

Influence of a Microwave Irradiation on the Swelling and Permeation Properties of a Nafion Membrane

“…We believe that the observed behavior may be due to the membrane deformation under a hydrostatic pressure difference applied which affects to the effective membrane surface exposed to the flow. Previous study has shown that polymeric Nafion membrane becomes deformed under an applied hydrostatic pressure showing the typical polymer viscoelastic behavior [44,45]. Both elastic and anelastic deformations contribute to the membrane area change.…”

On the electrokinetic characterization of charged polymeric membranes by transversal streaming potential

“…It has been reported elsewhere [45] that after applying a transmembrane pressure over polymeric membranes, an instantaneous pressure drop occurred, and afterward the pressure difference decreased for a few seconds until a stationary value was reached. This behaviour was attributed to the viscoelastic deformation of the membranes.…”

“…In particular, the mechanical properties of thin polymeric membranes are of wide interest to control processes because they affect the durability and lifetime, both related to the polymer degradation [41,42]. There is evidence that polymeric membranes can be affected by the application of a transmembrane pressure [43][44][45][46] originating polymer degradation. Thus, it is a very important issue in characterization techniques involving the application of a transmembrane pressure to know its effect on the membrane properties.…”