Fernández Pérez, JosefaParedes, XavierGaciño, Félix M.Pérez Comuñas, María JoséPensado, Alfonso S.2025-01-102025-01-102013Fernández J., Paredes X., Gaciño F., Comuñas M., and Pensado A. S. (2014), Pressure-viscosity behaviour and film thickness in elastohydrodynamic regime of lubrication of ionic liquids and other base oils, Lubr. Sci., 26, 449–462. doi: 10.1002/ls.1236https://hdl.handle.net/10347/38477This is the peer reviewed version of the following article: Fernández J., Paredes X., Gaciño F., Comuñas M., and Pensado A. S. (2014), Pressure-viscosity behaviour and film thickness in elastohydrodynamic regime of lubrication of ionic liquids and other base oils, Lubr. Sci., 26, 449–462. doi: 10.1002/ls.1236, which has been published in final form at https://doi.org/10.1002/ls.1236. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited.Viscosities at high pressures for 16 base oils (six polyolesters, three polyglycols, six ionic liquids and squalane) were used to analyze the influence of their chemical structure on the pressure-viscosity coefficient, α. Comparisons with literature α values for vegetable bases (canola, soybean and jojoba oils) are also performed. For the molecular lubricants, we found trends that are coherent with the literature, whereas for ionic liquids (ILs), new trends were found. ILs based on tris(pentafluoroethyl)trifluorophosphate anion [FAP]−are those which present higher α values. The role of the lubricants in the central thickness in the isothermal elastohydrodynamic regime of lubrication was evaluated through the product η00.69 α0.56, η0 being the viscosity at 0.1 MPa. One of the [FAP]− ILs provides film thicknesses close to the polyglycols with similar viscosity. Bis(trifluoromethylsulfonyl)imide ILs and the shorter polypropyleneglycoldimethyl ethers are the lubricants that better avoid the changes on the film thicknesses with the temperature owing to a high viscosity index.engPressure-viscosity coefficientFilm thicknessIonic liquidVegetable base oilsSynthetic base oilsjournal article10.1002/ls.12361557-6833open access