Tom McLeish

Tom McLeish

Durham University

1962 – Present

Theoretical Physicist
Awarded Bingham Medal 2010
Fellow, Elected 2015

Tom McLeish was born in, and grew-up in, south-east London. He received a B.A. and M.A. degree in Physics and Theoretical Physics from Emmanuel College, University of Cambridge in 1984. He remained in Cambridge to complete his Ph.D. in Polymer Physics, working as an ICI Research Fellow in the Theory of Condensed Matter Group at the Cavendish Laboratory from 1987 to 1989 and as a Fellow at Emmanuel College. He then became Lecturer in the Department of Physics at the University of Sheffield from 1989 to 1993. He moved to the University of Leeds in 1993 where he was appointed Professor of Polymer Physics, and director of the UK Polymer IRC. He moved to Durham University as Pro-Vice-Chancellor of Research in 2008, staying in that position until 2014. He is currently a Professor of Natural Philosophy at the University of York and serves as the Director of the EPSRC Centre for Doctoral Training in Soft Matter and Functional Interfaces.

During his Ph.D. thesis, Tom developed ‘tube model’ ideas to address the relaxation of entangled branched polymers, beginning with the ‘H-polymer’ architecture. As a post-doc, Tom and his former advisor, Robin Ball, applied the idea of “dynamic dilution” to star polymers, which he thereafter carried forward to branched polymers in general, with great success. Subsequently Tom developed the idea of “hierarchical relaxation,” whereby branched polymers of arbitrary architecture – including hyperbranched polymers – relax sequentially, starting from the tips of the arms. As they relax, they release constraints on other molecules, progressively “diluting” the density of constraints in the melt, as longer time scales are accessed. These ideas have become part of the basis of modern theories for relaxation and rheology of long–chain-branched (LCB) polymers, a very important topic both intellectually and commercially. Using dynamic dilution and other creative ideas, including the most rigorous version of Pino Marrucci’s “convective constraint release” (CCR) model, Tom and his coworkers published a series of papers predicting the linear and non-linear dynamics and rheology of linear, star-branched, “H”, and other polymers, which have become the “standard models” for relaxation and rheology of these systems. Working with experimental and computational collaborators in academia and industry alike, Tom applied these concepts to the observation and prediction of canonical polymer processing flows, such as flow through a contraction/expansion and cross-slot flows. This work combined anionic polymer synthesis, rheological measurement and theory, neutron scattering methods, polymer processing, and computational fluid dynamics, to build and test a practical constitutive model. The work consummated a long-sought goal of rheology: the encoding of experimental and theoretical rheological knowledge into an accurate yet practical constitutive equation useful for predicting the results of polymer processing operations. The approach is now used extensively in the polymer materials industry.

McLeish continues to work at the forefront of rheology and polymer physics and has twice been a recipient of the Journal of Rheology Publication Award. He now also works on biological soft matter physics, and on the history of science, especially in the medieval period. His books on the cultural position of science, Faith and Wisdom in Science and The Poetry and Music of Science, were published by OUP in 2014 and 2019, respectively, and he is frequently interviewed by news, radio, and T.V. journalists in the UK and Europe. His achievements have been recognized by both the 2010 Bingham Medal, the 2007 Weissenberg Medal of the European Society of Rheology, and election to Fellowship the Royal Society in 2011. He enjoys playing French horn, singing in ensembles, scuba diving, sailing, and hiking with his wife Julie and their now-adult children whenever they are around.


Tom McLeish. The Conversation (accessed Aug 22, 2019).

Tom McLeish FRS, Professor of Natural Philosophy. Department of Physics, University of York (accessed Aug 22, 2019).

Note: This biography is an adaptation of the following article previously published by The Society of Rheology.

Larson, Ron. Bingham Medalist 2010: Tom McLeish. Rheology Bulletin 2010, 79(2), 4.