Derivatizing l-histidine to develop a novel additive for a polyol-based biolubricant

Abstract

Two novel histidine Schiff base esters, HSE-A and HSE-B, were synthesized using a two-step reaction. The synthesized compounds were characterized using carbon, hydrogen, nitrogen analysis, Fourier-transform infrared and nuclear magnetic resonance spectroscopy. The antioxidant and anticorrosion properties of these additives were assessed using the universal oxidation test (IP-306) and standard accelerated corrosion testing procedure, which revealed that both additives have good antioxidant and anticorrosion properties. Lubricity test carried out in a four-ball test machine indicated that both additives could reduce wear when compared with the pure polyol base oil. Overall, the HSE-A additive is more effective than the HSE-B additive as an antioxidant/antiwear/anticorrosion biolubricant additive.