Soft Condensed Matter Seminar

Soft Condensed Matter Seminar

Designing and transforming yield-stress fluids


October 8, 2019 - 3:00pm to 4:00pm




Conference Room 1116



University of Illinois at Urbana-Champaign

Content Images


Yield-stress fluids can be engineered from a diverse range of microstructures including polymeric gels, colloidal glasses, emulsions, pastes, foams, and more. This talk will discuss our research on design thinking for yield-stress fluids (Nelson et al. Curr Opin Solid St M, 2019), addressing the rheology-to-structure inverse problem of the many ways to achieve a yield stress and important secondary properties including thixotropy and extensibility, e.g. for direct-write 3D printing. Microstructural considerations include conceptual models relating formulation to properties, quantitative models of formulation-structure-property relations, and chemical transformation strategies for converting effective yield-stress fluids to be more useful solid engineering materials. Future research directions are suggested at the intersection of chemistry, soft-matter physics, and material science in the context of our desire to design useful rheologically-complex functional materials.


Randy H. Ewoldt, Associate Professor, Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, conducts fundamental research in fluid mechanics and rheology. This includes new measurement methods and paradigms for design with materials such as yield stress fluids, polymer gels, and biological materials. His work has been recognized by awards from NSF (PECASE), ASME, 3M, DuPont, TA Instruments, and The Society of Rheology. His teaching has been recognized by awards from the College of Engineering and alumni of the University of Illinois. In 2018 he was a Guest Professor at ETH-Z├╝rich in the Department of Materials.