Synthesis and applications of boron-based ILs

In spite of ILs appealing physicochemical properties that perfectly fit specifications for high-performance lubricants, they were not studied in tribological contacts until a decade ago. 1 Some researchers have shown that a small family of ILs can also be incorporated into non-polar base oils, replacing traditional anti-wear additives, with excellent performance of the neat IL being maintained.2 Scientists have reported that BILs composed of [BF4]- anion and various alkylimidazolium cations [CnCmIm]+, n and m = 1, 2, 3. They concluded that alkylimidazolium tetrafluoroborates, [CnCmIm][BF4], have excellent lubricity in steel–steel, steel–aluminum, steel–copper, steel–SiO2, steel–Si(100), steel–sialon, and Si3N4–sialon ceramic contacts, making them attractive alternatives to conventional liquid lubricants.3 Most of the ILs successfully employed as lubricants in various ferrous and non-ferrous tribological contacts during the past decade and are predominantly based on the boronbased anion, [BF4]-. In this work, we report the synthesis and application of alkylimidazolium tetrafluoroborates of boron-based ILs. Initially, imidazole refluxed with sodium hydroxide in a THF solvent and 60°C. The resulting product was refluxed with 1-bromobutane and the viscous yellow liquid was obtained. Then addition of a halide salt to obtained mixture in room temperature forms ionic liquid.

کلیدواژه ها:

Ionic liquids ، Lubrican ، Lubricants additives ، Boron