On 28 October at 14:15 Triinu Vihmann will defend her doctoral thesis in materials science “Ionic liquids: synthesis and application in lubrication and lithography” for obtaining the Degree of Doctor of Philosophy.
Senior Research Fellow Uno Mäeorg, University of Tartu
Senior Research Fellow Kristjan Saal, University of Tartu
Dr. Karine Mougin, Institut de Science des Materiaux de Mulhouse (France)
New lubricants and improved antiwear additives are in need, because of increased service intervals, extreme conditions and regulations to reduced emissions. Ionic liquids are molten salts, which have unique properties (low volatility, high thermal stability) and recently have shown many advantages in this area. Nanoparticle is a small particle with size between 1-100nm. They have also been reported as lubricant additives due to their high-load tolerance and self-repair function to wear surface.
In the present thesis the synthesis of different ionic liquids was investigated. Moreover, task-specific imidazolium based ionic liquids with -OH groups are important for nanoparticle functionalization and ionic liquid adsorption to metal surfaces. Different ionic liquids and nanoparticles were investigated as lubricant and as lubricant additive and tribological measurements showed even up to 60% better performance. It is very important to achieve a stable dispersion of nanoparticles (carbon nanotubes, copper, titanium oxide) and therefore nanoparticles where cover with suitable layer.
Another interesting new application of ionic liquids is production and manipulation of microcantilevers in situ in SEM. It was shown that the hydroxyl group of ionic liquid has an important role in the polymerization/solidification process and affects the mechanical properties.