ChEMS Seminar: Structuring Liquids by Interfacial Jamming
Abstract: The ability to manipulate and lock-in the shape of one liquid in a second, i.e. structuring the liquids, allows the generation of unique materials that have the dynamics and mobility of liquids but the structural integrity of a solid. Bicontinuous fluids for separations, novel encapsulants for delivery systems, or all-liquid charge transport systems can be envisioned. Yet, these fluids have shapes that are far removed from their equilibrium shape, and developing routes to kinetically lock-in these non-equilibrium shapes while retaining the local fluidity is key. We describe the in situ generation of nanoparticle surfactants that assemble at the liquid/liquid interface. When the liquids are brought into non-equilibrium shapes, the nanoparticle surfactants will jam at the interface, freezing in the shapes of the liquids. External stimuli, as for example pH, electric or magnetic fields or temperature, can then be used to re-shape the liquids, so that the structured liquids can be adaptive. Alternatively, ultrathin films of polymers can be used as a surfactant, whereby placing the sheet at the interface, the interfacial energy and the free energy of the system are minimized. With only this driving force, ultrathin polymer sheets of a given shape will wrap around a second liquid, fully encapsulating the liquid.
Biography: Thomas P. Russell, the Silvio O. Conte Distinguished Professor of Polymer Science and Engineering at the University of Massachusetts in Amherst, received his doctorate in 1979 in polymer science and engineering from the University of Massachusetts Amherst. He was a research associate at the University of Mainz (1979-1981), a research staff member at the IBM Almaden Research Center in San Jose, CA (1981-96) and became a professor of polymer science and engineering at the University of Massachusetts Amherst (1997). He is currently at the Materials Science Division in the Lawrence Berkeley National Laboratory as a visiting faculty and a lead PI at the Advanced Institute of Materials Research at Tohoku University. His research interests include the surface and interfacial properties of polymers, phase transitions in polymers, directed self-assembly processes, the use of polymers as scaffolds and templates for the generation of nanoscopic structures, the interfacial assembly of nanoparticles, the influence of supercritical fluids on phase transitions and dynamics in polymer thin films, and wrinkling and crumpling behavior of thin polymer films. He was director of the Materials Research Science and Engineering Center from (1996-2009), director of the Energy Frontier Research Center on Polymer-Based Materials for Harvesting Solar Energy (2009-2014) and is now a lead princpal investigator in the WPI-Advanced Institute of Materials Research at Tohoku University and in the Global Research Laboratory at Seoul National University. He has over 670 publications, 21 patents and edited five books. He is a Fellow of the American Physical Society, Materials Research Society, Neutron Scattering Society of America, American Association for the Advancement of Science, and the American Chemical Society, Polymer Materials Science and Engineering Division. He has received the Polymer Physic Prize of the APS, the Cooperative Research Award of the ACS, the Dutch Polymer Award and the ACS Award in Applied Polymer Science. An elected member of the National Academy of Engineering, Russell has an h-index of 104.