Using a novel disulphide compound containing boron as a potential substitute for sulphurized olefins in lubricants

Abstract

A novel disulphide compound containing boron (DSB) was synthesized successfully and characterized, and its tribological properties in polyol esters were evaluated using a four-ball tribometer. The results indicate that DSB possesses excellent tribological properties. Moreover, DSB has no noticeable odour, little corrosion to copper, exhibits better thermal stability and antioxidant performance compared with sulfurized olefins. In order to study the action mechanism of the synthetic additive in friction process, a three-dimensional non-contact surface profilometer was used to explore the morphology of the worn surface and X-ray photoelectron spectroscopy analysis was carried out. It is found that tribological reaction occurred between DSB and metal surface, a film consisting FeSO₄ was formed, accompanied by the adsorption of decomposed borate ester and organic sulphide.