Rheology (from the Greek word “ρεολογία”) constitutes a branch of mechanics dedicated to the examination of material properties influencing their response to mechanical forces. Coined in the 1920s, the term “rheology” encapsulates the scientific investigation into the deformation and flow of matter. Its roots extend back to the 6th century B.C., credited to the insights of the Greek philosopher Heraclitus. He astutely observed, “Τα πάντα ρει, πάντα χωρεί και ουδέν μένει” (Ta panta rhei, panta hwrei, kai ouden menei), emphasizing the perpetual flux and dynamic nature of all things.

HSR

HSR was officially established on June 16th, 1996, in Athens, Greece, gaining recognition from the Greek judicial authorities due to the presence of the essential core of the first 20 founding members. This marked the realization of the initial efforts initiated by the late Professor Tasos Papanastasiou to organize the Greek Rheological community, alongside numerous scientists and engineers practicing rheology in their professional pursuits.

The inauguration of HSR was commemorated by the 1st meeting of the Society in Nicosia, Cyprus, held in July 1996. During this gathering, the 1st Executive was elected, with E. Mitsoulis assuming the role of President, and the Constitution was officially ratified.

The 2nd meeting of the Society convened in Heraklion, Crete, from August 31 to September 2, 1998, resulting in the election of a 2nd Executive for the term 1998-2000. Subsequent to this, the 3rd meeting unfolded in Cambridge on August 25, 2000. The most recent gathering, the 8th meeting, transpired in Limmasol (Cyprus) on July 13, 2017, during which the present Executive was elected for the period 2017-2019.

HSR has orchestrated ten Conferences in various locations, including Nicosia (1996), Heraklion (1998), Patras (2001), Vouliagmeni (2004), Rhodes (2007), Athens (2011), Heraklion (2014), and Limmasol (2017). The 9th HSR Conference, held from June 24 to 27, 2019, in Samos, Greece, honored Professor Gary L. Leal for his notable contributions to Rheology and Fluid Mechanics. The 10th Conference took place in Skiathos Island from June 29 to July 2, honored Professor Pino Marrucci and Evan Mitsoulis. Anticipating the 11th HSR Conference, scheduled for June, 2025, in Kefalonia/Ithakes, Greece, the Society continues to foster advancements in the field.

In April 2006, HSR played a pivotal role in organizing the 3rd Annual European Rheology Conference on behalf of the European Society of Rheology (ESR) in Hersonissos, Crete (Chaired by Dimitris Vlassopoulos & George Georgiou). Moreover, in July 2023, HSR collaborated in organizing and hosting the 19th International Congress on Rheology (ICR) in Athens, Greece (Chaired by Dimitris Vlassopoulos and Moshe Gottlieb).

Rheology permeates virtually every study of material properties, attracting physicists, chemists, engineers, biologists, and mathematicians. The Society, though modest in size with approximately 40 members, encompasses a diverse range of individuals from academic, industrial, and governmental institutions. Their activities span phenomenological and molecular theories, instrumentation, and the examination of various materials, including polymers, metals, petroleum products, rubber, paint, printing ink, ceramics, glass, foods, biological materials, floor preparations, cosmetics, and an array of practical applications.

As one of the fifteen founding members of the European Society of Rheology, the Hellenic Society of Rheology maintains an affiliation. Additionally, the Society holds membership in the International Committee on Rheology, which oversees the organization of the International Congress on Rheology.