
Professor of Chemical Engineering and (by courtesy) of
Materials Science and Engineering
BS, chemical engineering, 1985, University of Illinois
MS, chemical engineering, 1986,
University of Illinois
PhD, chemical engineering, 1991, Stanford University
We seek to understand the dynamics of complex
fluids during flow. Many fluids encountered in materials processing exhibit
non-Newtonian behavior due to the presence of complex molecular or nanoscale
structure that is perturbed by flow. Our research emphasizes in-situ investigation
of such flow-induced structural changes to elucidate the origins and mechanisms
of complex rheology in polymers.
Our research is broadly divided between two thrusts.
We have a long-standing interest in how flow affects the organization of structured
fluids such as surfactants, ordered block copolymers, and liquid crystalline
polymers. We use powerful X-ray scattering techniques for realtime measurements
of polymer structure in both idealized shear flows and during processing, taking
advantage of Northwestern's synchrotron research facility at the Advanced Photon
Source. Our other theme is the application of unique flow birefringence techniques
to interrogate stresses generated in polymer melts and solutions and to test
theoretical models for the rheological behavior of flexible polymers.
Fellow, American Physical Society, 2004
Young Investigator Award, National Science Foundation
McCormick Teaching Award
Mortar Board Honor Roll of Outstanding Teachers
Allan P. Colburn Lecturer, University of Delaware
John H. Dillon Medal, American Physical Society
Transient molecular orientation and rheology in flow-aligning
thermotropic liquid crystalline polymers [with V. M. Ugaz, W. Zhou, and
J. A. Kornfield]. J. Rheol. 45: 1029-63 (2001).
F. E. Caputo, W. R. Burghardt, K. Krishnan, F. S. Bates and T. P. Lodge, "Time-Resolved
Small-Angle X-ray Scattering Measurements of a Polymer Bicontinuous Microemulsion
Structure Factor under Shear," Phys. Rev. E 66,
041401 (2002).
J. Bang, T. P. Lodge, X. Wang, K. L. Brinker and W. R. Burghardt, "Thermoreversible,
Epitaxial fcc<-> bcc Transitions in Block Copolymer Solutions," Phys.
Rev. Lett. 89, 215505 (2002)