Guiseppe Marrucci
University of Naples Federico II
1937 – Present
Chemical Engineer
Awarded Bingham Medal 2003
Fellow, Elected 2015
Giuseppe (Pino) Marrucci completed his higher education at the University of Naples, graduating with his Chemical Engineering Ph.D. in 1961. He remained at the University following graduation,
serving as Assistant to the Chair of Industrial Chemistry and working his way into an Associate Professor of Chemical Engineering position (1965). Marrucci accepted a position as Chair of
Principles of Chemical Engineering at the University of Palermo in 1970. He returned to the University of Naples in 1976, accepting chair positions in Non-Newtonian Fluid Mechanics as well
as Thermodynamics. Marrucci remained at the University of Naples for the remainder of his career, strengthening its reputation and activity as a destination for rheology.
Marrucci is particularly well-known for his work in three key areas; entangled polymer melts, liquid crystalline polymers and, more broadly, development of constitutive equations for
understanding and modeling non-Newtonian flows. After the introduction of the seminal Doi-Edwards theory in 1978, the two most important advances to this theory for the rheology of
flexible-chain polymers have been due to Marrucci and coworkers. First was the addition of "chain stretch" to the basic equation which enabled overshoots in normal stresses to be predicted.
Subsequently Marrucci introduced the concept of "convective constraint release" (CCR), which corrected the tendency of tube models to predict excessive shear-thinning in very fast flows.
In 1989, Marrucci and Maffetone explained the cause of the mysterious negative first normal stress difference in shearing flows of nematic polymers. The explanation involved director tumbling,
by which shearing flows actually cause the molecules to be less aligned than in the absence of shear, producing a reactive force that is opposed to the shearing direction, giving rise to a
negative N1. In the early 1990's, Marrucci and Greco developed a theory for the structure of a defect core that can be applied to flowing liquid crystals. When combined with
the "Doi theory" for nematic polymers, this theory allowed the development of numerical solutions for the director field in flowing liquid crystals, and it has subsequently been widely used.
In addition to these contributions to the molecular physics of rheology, Marrucci has never lost sight of the importance of rheology as an engineering discipline and his group produced numerous
simplified constitutive equations, useful for calculating the stresses in complex flows including a simplified differential version of the Doi-Edwards equation (the “DEMG” model), that
significantly improved the normal stress predictions of that equation in strong shear and extensional flows.
Marrucci’s service to rheology extends well beyond his scientific contributions. He has regularly hosted or co-hosted rheology meetings, including three meetings on the island of Capri near his
beloved University of Naples and the VIIIth International Congress on Rheology in Naples (1980). Marucci was awarded the
Bingham Medal in 2003. He is a wonderfully clear communicator and a spirited participant in the international community
of rheologists whose contributions are always marked by a rare combination of intelligence and grace.
Sources
Macosko, Christopher Ward. American Men and Women of Science, 27th ed.; Gale: Farmington Hills, MI, 2010; Vol. 5.
Tanner, R. I.; Walters, K.
"4.16 Giuseppe Marrucci."
Rheology: an historical perspective, Elsevier: Amsterdam, 1998.
Note: This biography is an adaptation of the following article previously published by The Society of Rheology.
Guiseppe Marrucci 2003 Bingham Medalist. Rheology Bulletin 2003, 72(2).