Tribological properties of trimethylolpropane oleate synthesized through esterification reaction with nano-MoS2 catalysts of different shapes

Abstract

PurposeThis study aims to investigate the catalytic performance and tribological properties of MoS2 powder.Design/methodology/approachIn this work, the authors attempted to use MoS2 nanoparticles (nano-MoS2) as a catalyst to synthesize trimethylolpropane oleate (TMPTO) by esterification of trimethylolpropane and oleic acid. The small amount of highly dispersed nano-MoS2 catalyst remaining in TMPTO needed not to be separated and could be used as a lubricant modifier directly to achieve the purpose of improving the lubricity performance of TMPTO.FindingsThe results demonstrated that nano-MoS2 had good catalytic esterification ability and achieved in situ dispersion of about 0.191% nano-MoS2 in TMPTO while catalyzing the synthesis of base oil. After high-speed centrifugal sedimentation treatment, the product TMPTO still retained about 0.008% of nano-MoS2. The above-synthesized TMPTO has significantly better lubricity performance than commercially available TMPTO, in which the friction coefficient and wear rate could be reduced by 75%.Originality/valueThe results of this study provide an idea for the design of catalysts for ester oil synthesis.