Pressure dependence on the viscosities of 1-butyl-2,3-dimethylimidazolium bis(trifluoromethylsulfonyl)imide and two tris(pentafluoroethyl)trifluorophosphate based ionic liquids: New measurements and modelling

Volumetric behaviour of six ionic liquids from T = (278 to 398) K and up to 120 MPa

“…In general, the compressibility of ILs is much lower than that of standard hydraulic mineral oils and even lower than that of water [3] in several cases under broad temperature and pressure conditions. Besides, in previous papers [16][17][18][19] we have found that most of the ILs analysed have low pressure-viscosity coefficients in comparison with most of the conventional lubricants. According to Mia and Ohno [20], high bulk modulus fluids having low pressure-viscosity coefficient, indicate an efficient hydraulic fluid.…”

Pressure‐viscosity behaviour and film thickness in elastohydrodynamic regime of lubrication of ionic liquids and other base oils

“…ILs samples were kindly provided by Merck KGaA (Darmstadt, Germany). Before measuring the properties, we dried the ILs under constant stirring and moderate vacuum to remove the residual volatile impurities at room temperature . The water content was assessed by means of Karl–Fischer titration.…”

“…Estimated experimental uncertainty of VisLPT1 and Ruska ranges from 3% to 5%, depending on the calibration method, the reference fluids and the viscosity ranges used. Viscosities of squalane, PAGs and esters were measured by using the Ruska viscometer, those of the ILs were carried out with VisLPT1 …”

“…In this work, we present an analysis of the VI as well as the derived properties obtained from the measurements of the viscosity at high pressures (the pressure‐viscosity coefficient and the film thickness) performed in our laboratory for 16 unformulated lubricants of different type (POEs, PAGs and ILs). In addition, comparisons with results published by Biresaw and Bantchev on vegetable bases (canola, soybean and jojoba oils) are also performed.…”

On the viscosity of two 1-butyl-1-methylpyrrolidinium ionic liquids: Effect of the temperature and pressure

“…Therefore the calibration of the devices has to be carried out carefully and as accurately as possible in order to minimize the contributions of the uncertainty in the viscosity measurements. Despite of the large amount of studies of viscosity of ILs at atmospheric pressure, the viscosity database of ILs at high pressure is still scarce [10,15,[29][30][31][32].…”