Self-constraint gel lubricants with high phase transition temperature

Self-constraint gel lubricant with high phase transition temperature (HTG) is reported, and their physicochemical properties, tribological performances, and lubrication mechanism are assessed in the paper. The HTG is (2R)-2-(3,4-dichlorophenyl)-6-(1,2-dihydroxyethyl)-5-hydroxy-N-octyl-1,3-dioxane-4-carboxamide, and it can assemble through multiple intermolecular interaction (hydrophobic interaction plus hydrogen bonding interaction and π-stacking interaction) to form a fibrous structure that can effectively trap base oils. The gel can greatly enhance the phase transition temperature up to 190 °C and reduce the friction heat from 47.5 °C (base oils) to 38 °C at a rotating rate of 1450 rpm at 392 N for 30 min. When used in fully formulated oil, the gel lubricants show excellent lubricating and antiwear properties, which is believed that the introduction of chlorine makes a significant contribution. Excitingly, the gel having thermal reversibility, creep recovery, and thixotropic properties can be infiltrate...