H. Henning Winter

University of Massachusetts Amherst

1941 – Present

Chemical Engineer

Awarded Bingham Medal 1996

Fellow, Elected 2015

H. Henning Winter obtained a Dipl-Ing. at the University of Stuttgart (UStgt), an MS degree from Stanford University, and a PhD (summa cum laude) in Chemical Engineering from UStgt. He wrote his habilitation thesis in the area of rheology, an interest he continued pursuing immediately after graduation through work as a DFG (German Research Foundation) fellow at the Rheology Research Center at the University of Wisconsin Madison. Winter began his teaching career as Privatdozent for Rheology at Stuttgart in 1976. He became an Associate Professor in Chemical Engineering at the University of Massachusetts Amherst in 1979, was promoted to Professor in 1984, and was named Distinguished Professor in 2004. At the same time, he also became both the Director of the Laboratory for Experimental Rheology and Adjunct Professor of Polymer Science and Engineering.

Winter was awarded the Bingham Medal of The Society of Rheology in 1996, in recognition of his outstanding contributions to experimental rheology as well as rheometry of gels and polymer melts. In a series of groundbreaking papers, Winter and his co-worker F. Chambon characterized the time-evolving rheology of polymers during gelation. They discovered that the gel point of polymers is marked by power-law relaxation over a wide range of frequencies/time-scales. The simplicity of the behavior at the gel point is quite striking and the behavior discovered by Winter and his group makes it easy to uniquely identify the gel point during both chemical and physical gelation processes. Their original paper continues to be the most cited paper ever in the Journal of Rheology (Winter & Chambon, 1986). Winter and his co-worker M. Baumgaertel also wrote the first robust code (based on a “parsimonious model” formulation with a minimal number of adjustable parameters) to convert dynamic mechanical data into the corresponding relaxation time spectrum. Together with A. Schausberger, they showed that linear, flexible polymers of uniform chain length relax in a self-similar relaxation time spectrum now known as the BSW spectrum. The readily identifiable BSW parameters are the plateau modulus, the longest relaxation time, the glass transition time, and two scaling exponents. Winter also contributed to the numerical modeling of polymer processing operations and his 1977 paper on viscous dissipation in flowing polymer systems is widely considered a classic in the area. His ongoing research interests include connections between gelation and the glass transition, flow-induced crystallization and the development of advanced rheometrical analysis tools such as the software package IRIS.

Winter served as the Editor of Rheologica Acta from 1990 till 2016 and as member of several editorial boards. In addition to the Bingham Medal, he was chosen for the National Science Foundation Creativity Award in 1997 and the Alexander von Humboldt Senior Scientist Award in 1999 during which he was a visiting professor at the Max Planck Institute for Colloids and Interfaces in Potsdam.