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 infiltrated into porous poly based bearing materials, which not only reduces the problem of throwing oil but achieve self-lubrication. These advantages of the gel help keep the environment green and clean and save energy. So, the gel is expected to be applied in peculiar machine components and the condition where temperature increase facilitates oil spreading and makes sealing much more challenging.