Professor
PhD Graduate Advisor, Associate Head (Research)
Office: CHBE 243
Email: savvas.hatzi@ubc.ca
Research Summary
Rheology of Polymers, Polymer Blends and Suspensions, Associating Polymers, Non-Newtonian Fluid Mechanics, Polymer Processing
Education
McGill University, 1991, Ph.D.
University of Toronto, 1988, M.Sc.
Aristotelion University of Thessaloniki, 1984, Diploma (ptychion)
Research interests + projects
The rheology and mechanical properties of associating polymers (ionomers and hydrogen bonding polymers) is of particular interest in our research program. Due to the presence of reversible associations, these polymers exhibit many idiosyncrasies, rich chain dynamics and unique properties such as self-healing and adhesion. The main thrust of this program is to study their non-linear viscoelasticity and self-healing behaviour using novel rheo-mechanical techniques to explore their potentials in applications such as coatings, packaging, 3D printing, adhesion and blend compatibilization.
Non-Newtonian fluid mechanics is often distinguished from its Newtonian counterpart by the additional requirement that first a constitutive equation be specified as part of the problem statement and secondly a suitable wall boundary condition other than the no-slip be imposed as a necessary ingredient. The main thrust of this part of the research program is both a theoretical and an experimental study of diverse complex fluid-wall interfaces under flow.
The interplay between thermodynamics and rheology of polymer blends is of particular interest. During flow of polymer blends, there is a variety of phenomena that may take place such as shear induced mixing and de-mixing. These effects are dramatic as the homogeneous region in their (polymer blends) phase diagram may be shifted or enlarged by several degrees under flow. This part of the research program focuses on the rheological and thermodynamic behavior of polymer blends under flow (shear/extensional), the resulting morphology and its effects on the mechanical properties of final products.
Professor Hatzikiriakos and his students have published over 250 papers. He has edited a book entitled Polymer Processing Instabilities: Understanding and Control. His group is actively collaborating with the University of Crete and the National Technical University of Athens. Professor Hatzikiriakos also serves as an expert witness in polymer patent litigation and dispute and as a consultant to polymer industry.
Awards and honours
Fellow of the Engineering Institute of Canada (FEIC) , 2021
Fellow of the Society of Rheology (FSOR) , 2020
Mason Award of the Canadian Society of Rheolofy , 2014
Fellow fo the Canadian Academy of Engineering (FCAE) , 2013
Best paper awars in Journal of Rheology , 1992, 2010
Scholarly and professional activities + affiliations
Deputy Editor, Physics of Fluids
Certified Member, Professional Engineer in Canada (British Columbia)
Member, Canadian Society of Rheology
Member, The Society of Rheology
Selected publications + presentations
B.M. Yavitt, T. Tomkovic, D.J. Gilmour, Z. Zhang, N. Kuanr, E. van Ruymbeke,L.L. Schafer and S.G. Hatzikiriakos “Rheology and Self-healing of Amine functionalized Polyolefins,” J Rheology, 66, 1125-1137 (2022)
D. Gilmour, T. Tomkovic, N. Kuanr, M. Perry, H. Gildenast, S.G. Hatzikiriakos and L. Schafer, “Catalytic amine functionalization and polymerization of cyclic alkenes creates adhesive and self-healing materials” ACS Applied Polymer Materials, 3, 2330-2335 (2021) https://doi.org/10.1021/acsapm.1c00158
M. Najm, B. Yavitt and S.G. Hatzikiriakos, “Synergistic ionic interactions in EMAA ionomer blends: A rheological and mechanical property investigation,” J. Rheology, 65, 1373-1389 (2021) https://doi.org/10.1122/8.0000323
M. Najm and S.G. Hatzikiriakos, “Flow-Induced Fractionation Effects on Slip of Polydisperse Polymer Melts,” Physics of Fluids, 32, 073109 (2020) https://doi.org/10.1063/5.0017996
N. Ghahramani, K. Iyer, A.K. Doufas and S.G. Hatzikiriakos, “Rheology of Thermoplastic Vulcanizates (TPVs),” J. Rheology, 64, 1325-1341 (2020) https://doi.org/10.1122/8.0000108