... inaccessible to polymers because of the ·too large dimensions of macromolecules compared to pore throats. More recently, thermo- dynamic arguments predicting differences in polymer concentration. at equilibrium between bulk solution and pore wall vicinity and thus between pores of different sizes have been...

... and partly elongational flows through channels having well-known dimensions. The dilatant behavior can be explained by the coil-stretch transition of macromolecules in elongational parts of flow. This stretching gives a detectable increase in viscous friction and thus the onset of dilatancy as soon...