Vegetable oil-based ionic liquid microemulsions and their potential as alternative renewable biolubricant basestocks

This paper reports the successful formulation of microemulsions with vegetable oil as the continuous phase, room-temperature ionic liquid (IL) 1-butyl-3-methyl-imidazolium tetrafluoroborate as the polar phase, TritonX-100 as the surfactant, and 1-butanol as the cosurfactant. A pseudo-ternary phase diagram, dynamic light scattering data, UV-vis spectra, and kinematic viscosity measurements were employed to characterize and analyze the phase behavior and microstructure of the vegetable oil-based IL microemulsions. The tribological properties of the designed microemulsions were evaluated using a four-ball tester. The results confirmed the formation of an IL microemulsion containing vegetable oil. The designed petroleum-free microemulsions exhibit excellent viscosity-temperature characteristics and friction-reduction proprieties, indicating the tremendous potential of IL microemulsions as renewable biolubricant basestocks. (C) 2013 Elsevier B.V. All rights reserved.