Professor Ivan B. Ivanov passed away in Sofia on 15th of May 2018 at the age of 82. He was a remarkable scientist working in the field of colloid and interface science with basic contributions to physicochemical hydrodynamics and thermodynamics of thin liquid films and fluid disperse systems – foams, emulsions and suspensions [1].
His most important contributions are related to the theoretical description and experimental investigation of the mass transfer processes that govern the thinning of liquid films and interactions of bubbles in foams and drops in emulsions in the presence of surfactants; hydrodynamic explanation of the empirical Bancroft rule of emulsion stability; quantitative theory of the critical thickness of rupture of liquid films; complete thermodynamics of thin liquid films; stratifying films; capillary forces between particles, and properties of protein stabilized emulsions.
He was Dean of the Faculty of Chemistry of Sofia University (1979-1986) and founded the Laboratory of Thermodynamics and Physicochemical Hydrodynamics (1983), now – Department of Chemical and Pharmaceutical Engineering. His high erudition, inventiveness and remarkable communicative abilities (he spoke fluently several languages) helped Ivan B. Ivanov to create numerous joint international research and industrial projects. He was an inspiring lecturer who drew the students’ attention to the fascinating world of physical and colloid chemistry, provoked their curiosity, and awaked their striving for scientific knowledge. He had the ability to attract capable young people. Fifteen of his former students are now full professors in Europe and in the USA.
The great scientific legacy of Ivan B. Ivanov will keep forever the memories for him.