Experimental investigations on electrorheological properties of lubricating oils containing ionic liquid. Part. 1. Investigations with modified Brookfield DV-III Ultra Viscosimeter

The results of experimental investigations on electrorheological (ER) properties of lubricating oils which contain ionic liquids, are presented in this article. The investigations were carried out on the special stand which was projected for this aim. On this stand there was used the modified Brookfield viscosimeter. Electrorheological properties of two mixtures were tested, i.e., silicone damping liquid GP-1 which is polimethylsiloksane mixture containing 2% (v/v) of ionic liquid CJ 001, i.e., tetrafluoroboran 1-methyl-3-octyloxymethylimidazolium as well as base polialfaolefine oil PAO-6 which contains 2% (v/v) of ionic liquid CJ 008, i.e., trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)imide. Selection of components of both mixtures was based on the results of investigations of miscible and on evaluation of basic phys-chem properties. The investigations showed that the made mixtures have generated the ER effect, but it was short-lived effect, suggesting the changes of inner structure of these mixtures. Therefore, we have planned the next investigations, among others dielectric spectroscopy and microscope observations in situ of these mixtures in external electric fields. The aim of those investigations will be to record the fading ER effect and to understand this mechanism. Keywords: electrorheological effect, homogenous mixtures, lubricants, ionic liquids