Our research is focused on microscopic, physical understanding of the unique material properties of polymers and complex fluids. The hallmarks of these “soft” systems are:
- interplay between entropic fluctuations and energetic tendency to order;
- exquisite sensitivity of structure to imposed fields, including deformation and flow.
These features of soft systems afford unique opportunities for design of material properties, but also pose theoretical challenges. Material design in the vast parameter space of complex fluids cannot be achieved by a strictly empirical approach, but requires conceptual understanding as well, to exploit the potential of these remarkable materials.
Current research areas include:
- glassy systems (including dense fluids, polymer thin films, and plasticized polymers)
- ordering and crystallization (including polymer miscibility, polymer nematics, crystal nucleation in polymers, and flow-induced crystallization)
- polymer entanglement (including effect of polymer stiffness, entanglement in mixtures)
- semiconducting polymers (including charge transport in polymers for organic electronics and photovoltaics)
We employ a wide range of theoretical tools to solve problems. Broadly speaking, we use whatever it takes. Our computational methods include:
- atomistic simulations
- coarse-grained simulations
- Monte Carlo simulations
- self-consistent field theory
- analytical theory
- scaling arguments