View Full CalendarThis calendar includes all events from the following individual calendars: Department of Chemistry Alumni Events (events for an alumni audience), Department Events (events of general interest and/or relevant to all Chemistry research areas), Diversity, Equity, and Inclusion Events, Public Events, and events related to Chemistry research areas and programs (Analytical Chemistry, Chemical Biology, Chemistry-Biology Interface Training Program, Inorganic Chemistry & Materials Chemistry, Organic Chemistry, Physical Chemistry), as well as Department of Chemical and Biomolecular Engineering Seminars & Events.
CHBE 565 Seminar, Professor Ravi Jagadeeshan, Monash University, "The Dynamics of
Polymer Solutions at Finite Concentrations"
- Event Type
- Seminar/Symposium
- Sponsor
- Chemical and Biomolecular Engineering
- Location
- 1092 Lincoln Hall
- Date
- Oct 29, 2019 4:00 pm
- Contact
- Christy Bowser
- E-Mail
- cbowser@illinois.edu
- Views
- 75
- Originating Calendar
- Chemical & Biomolecular Engineering - Seminars and Events
Many important phenomena in both industrial and biological contexts involve polymer solutions at finite concentrations–in the so-called semidilute regime. However, the behaviour of polymer solutions is presently well understood only in the dilute and concentrated solution limits. I review the investigations of the dynamics of semidilute solutions in our group, through experiments and computer simulations, over the past few years. The experiments probe the linear and non-linear viscoelastic behaviour of solutions of polystyrene and DNA in a wide range of molecular weights, temperatures and concentrations. The dependence of the zero-shear rate viscosity on concentration is observed to display universal behaviour that can be understood within the framework of the blob theory for semidilute polymer solutions. Further, the shear rate dependence of viscosity at various temperatures and concentrations can be collapsed onto master curves when understood in terms of a relaxation time that depends on concentration. Computational prediction of the static and dynamic properties of semidilute polymer solutions requires the simulation of a large system of polymer chains interacting with each other through excluded volume and hydrodynamic interactions. We describe the development of a Brownian dynamics simulation algorithm that uses a fast implementation of the Ewald summation method to predict the behaviour of flowing polymer solutions at finite concentrations. In
particular, we use the algorithm to examine the response of single chains in a semidilute solution when subjected to a step-strain deformation followed by cessation of flow. A systematic comparison of simulation predictions is carried out with the experimental observations of Schroeder’s group, who have recently used single molecule techniques, in the context of semidilute solutions flowing in a cross-slot cell, to investigate the stretch-relaxation of individual λ-phage DNA chains.
