Ultra-short running-in period and robust lubricity constructed by dynamic disulfide and hydrogen bonds from ionic liquid polyethylene glycol lubrication

Polyethylene glycol (PEG) system behave the characteristics of non-toxic, non-irritating and good compatibility with various substances, so the improvement and stability of lubrication property and comprehensive performance is vital for PEG system under harsh working conditions. Here, highly reactive ionic liquids (ILs) are designed and introduced with a specifically designed molecular structure, the ultra-short running-in period and robust lubricity can be obtained by dynamic disulfide and hydrogen bonds from the constructed IL-PEG200 lubrication system. Combined with analytical techniques (XPS, FIB-TEM, Nanoindentation, Raman, TOF-SIMS), their interaction was explored to further clarify the interfacial self-assembly behavior. The superior bearing capacity is mainly ascribed to the synergistic effect of carbon-like film, dynamic disulfide bond, hydrogen bonding and interfacial tribochemical reaction.