Ionic Liquid Lubricant Composition for Conductive Low-Polarity Oils

The patent uses a composite ionic liquid system combining two different ionic liquids (IL1 and IL2) with complementary properties. IL1 provides solubility in low-polarity base oils while IL2 provides the electrical conductivity enhancement. This composite approach allows the lubricant composition to achieve both good solubility and reduced electrical resistance simultaneously, resolving the contradiction between solubility and electrical conductivity improvement.

IL1 acts as an intermediary substance that facilitates the incorporation of IL2 into the low-polarity base oil. By first ensuring IL1 is soluble in the base oil, the system creates a compatible medium that can then accommodate IL2, which would otherwise be insoluble. This intermediary approach enables the indirect introduction of the conductivity-enhancing ionic liquid without direct solubility issues.

The patent segments the functionality into two distinct ionic liquids: IL1 (with phosphate/carboxylate anions) handles the solubility function in nonpolar oils, while IL2 (with perfluoroalkylsulfonyl anions) handles the electrical resistance reduction function. This segmentation allows each ionic liquid to be optimized for its specific role, with IL1 providing compatibility and IL2 providing the electrical conductivity enhancement that single-ionic-liquid systems cannot achieve.

The patent changes the anion parameter of the ionic liquids to achieve different functions. IL1 uses phosphate or carboxylate anions for solubility compatibility, while IL2 uses perfluoroalkylsulfonyl anions (such as bis(trifluoromethylsulfonyl)imide or tris(pentafluoroethyl)trifluorophosphate) for superior electrical conductivity enhancement. By varying this key chemical parameter, the system optimizes both solubility and electrical resistance reduction.