William W. Graessley
Northwestern University
September 10, 1933 – February 18, 2017
Chemical Engineer
Awarded Bingham Medal 1979
Dr. William “Bill” Graessley was born in Muskegon, Michigan on September 10, 1933. He attended the University of Michigan for his undergraduate and graduate education,
receiving both a B.S. in Chemistry and a B.S.E. in Chemical Engineering in 1956 before completing his Ph.D. in Chemical Engineering in 1960. He subsequently worked for
the Air Reduction Company from until 1963 and then took a position as Professor of Chemical Engineering and Materials Science at Northwestern University. Graessley
returned to the private sector in 1982 to work as a senior scientific advisor at Exxon’s Corporate Research Laboratories in Clinton NJ. He ended his career back in
academia, accepting a position as Professor of Chemical Engineering at Princeton University in 1987 and working there until his retirement in 1998.
Dr. Graessley was a pioneer in the field of molecular rheology, exploring the structural aspects of polymer rheology, polymerization reactor kinetics, and molecular
characterization. His research focused on two main topics: the entanglement of polymers at the molecular level and the mixing of polyolefins. He proposed a useful
graphical representation, now commonly known as a Graessley Diagram for understanding the variety of different viscoelastic states (i.e. dilute, semi-dilute or
concentrated and unentangled/entangled) that a liquid polymer system may find itself in as the concentration, molecular weight and solvent quality are varied.
Graessley’s work with entangled polymer mixtures was crucial to developing a better understanding of polymer melt rheology, especially when two or more distinctly
different molecular weight species were mixed together. After his retirement, Graessley wrote two books on polymeric liquids and networks that are highly respected
and routinely referenced in the field.
Over the course of his career, Graessley advised thirty-one Ph.D. students, contributed to the formation of the Princeton Materials Institute and the Princeton Center
for Complex Materials, and also devoted six years to working as the assistant editor for the Transactions of the Society of Rheology. He was a member of the National
Academy of Engineering and received the Polymer Physics Prize from the American Physical Society as well as the Bingham Medal from The Society of Rheology. Graessley
was known to be an open-minded, dedicated scientist whose legacy extends well beyond the lab.
Sources
Rheology Bulletin 1979, 48(1). Also in Society of
Rheology Miscellaneous Publications, Box 6, Folder 32. Niels Bohr Library & Archives, American Institute of Physics. One Physics Ellipse, College Park, MD 20740.
Sullivan, John. “William Graessley, emeritus chemical engineering professor and polymer expert, dies at 83.”
Princeton University. March 29, 2017.
"William Walter Graessley."Prabook.com.
(accessed July 26, 2018).
Wang, Linda. William W. Graessley. Chemical & Engineering News 2017, 95(26).