Sulfur Carriers

Free Radical Addition of Butanethiol to Vegetable Oil Double Bonds

“…In many petroleum- and vegetable oil-based lubricant formulations, sulfur-containing compounds are commonly introduced as additives to improve wear and friction properties by maintaining boundary lubricating properties through physical and chemical adsorption to metal . For example, sulfurized vegetable oils obtained by reaction between elemental sulfur and vegetable oils have been found to provide good extreme-pressure and antiwear properties − . However, the sulfurization process must be carefully controlled and the total sulfur content maintained below 10%.…”

Surface Film Adsorption and Lubricity of Soybean Oil In-Water Emulsion and Triblock Copolymer Aqueous Solution: A Comparative Study

“…Contrary to fatty acids, which provide adhesive chemical layers on the surface through polar bonding and chemical reactions, copolymer solutions adsorb through hydrophobic interactions between the PPO blocks and the metal surface. Physically formed layers of copolymer solutions are readily rinsed due to non-polar behaviour [52]. Moreover, desorbed copolymer films have lower tendency to readsorb during the dynamic film regeneration [53].…”

“…In the boundary lubrication during the sliding contact between rubbing surfaces and due to high shear forces, bond cleavage between CH2 segments of fatty acids may occur [25,49]. At 30 °C, the soybean droplets film on the surface is not strongly adhered through the polar bonds and cannot withstand the high shear force and the dynamic nature of the sliding test [49,52,53]. At 65 °C, soybean VO/W emulsions provide substantially better lubricity, primarily attributed to the induced chemical reactions of the adsorbed film with the surface oxide layer that triggers the surface chain polymerisation [48,49,53,61].…”