Abstract: Polymer gels are scientifically and technologically important materials, as they can be handled like solids, while still affording liquid-like diffusion rates. A long-standing challenge in this area is that while the spatial distribution of crosslinks in most gels are known to be non-uniform on the nano- and micro-scale, important details of their structure, which impact mechanical and transport properties, have remained elusive. In this talk, I will present my group’s findings in applying super-resolution microscopy (i.e. the ability of far-field fluorescence microscopy to image at nanoscale resolutions using visible light) to the study of a model system of spatially inhomogeneous hydrogels. These advances include a greater understanding of the structure of spatial heterogeneities in thermosensitive gels, new insights into what causes them to form, and the discovery and explanation of new trends in how they can affect mechanical properties.
About the speaker: Chaitanya Ullal is an Associate Professor in the Department of Materials Science and Engineering at the Rensselaer Polytechnic Institute. He earned his PhD in Materials Science and Engineering at the Massachusetts Institute of Technology (MIT) and did a post-doc in the lab of Stefan Hell at the MPI-BPC in Germany. He is a recipient of the NSF CAREER Award, the ACS PRF New Investigator Award, and the Eastern NY Alfred H. Geisler Memorial Award. His research interests are related to unconventional nanofabrication, optics, and polymers. A current emphasis of the group is the use of optical microscopy with nanoscale resolution to image and pattern nanostructured polymers.