Soft Matter Under Stress: shear banding and structure formation

Tuesday, November 13, 2012 - 3:15pm - 4:15pm
Regents 109
Peter Olmsted
School of Physics & Astronomy, University of Leeds

The delicate nanostructure of soft matter, such as polymers, emulsions, and colloidal suspensions, can be self assembled or controlled for a variety of fascinating applications familiar in everyday life; this allows us to also study a variety of fundamental ideas about phase transitions, statistical mechanics, and non-equilibrium physics. Precisely because of the soft nanostructures, these materials are strongly susceptible to mechanical stresses and flow fieilds. I will explore these ideas in the context of “shear banding fluids”, such as wormlike micelles, entangled polymer solutions, and liquid crystalline materials. The interplay between mechanics gives rise to hydrodynamic instabilities and transitions in soft matter in flow, whose understanding is crucial to many common products such as plastics, shampoos, and pastes.

Host:  Jeff Urbach