Synthesis of boron ester-containing additives for lubrication

Lubricating oil is a functional material applied for separating two surfaces. During the last decades, additives have been added to the lubricants to give them special properties and improve their lubrication performance.1 Boron and boronate compounds are widely used in a range of tribological applications such as friction modifiers, antioxidants, antiwear additives, and in many cases as environmentally friendly lubricants oils and fuels. To improve the hydrolytic stability of borate esters, the addition of some amine compounds to produce additional molecular coordination is used.2 added of electron-rich groups (such as nitrogen atom) into borate ester, to stabilize the electron-deficient of boron atom, and that can reduce the possibility of attack by some nucleophiles. More importantly, it can enhance antiwear performance for the synergetic effect between boron and nitrogen element.3 Herein, we report the synthesis of boron ester-containing additives to improve the performance of a lubricating oil from the reaction between fatty acids and boric acid with secondary amine in toluene solvent at 250 °C. Finally, a reddish viscous liquid was obtained. It has the ability to dissolve in oil, as well as its antioxidant properties and viscosity. All synthesized compounds are stable materials whose structure is based on their mass spectra, 1H and 13C-NMR and IR spectroscopy data.

Keywords:

Boron ester , Antiwear , Antioxidant , Lubricant , Additives