Covalently attached mesoporous silica–ionic liquid hybrid nanomaterial as water lubrication additives for polymer-metal tribopair

In order to further enhance the tribological performance of a polyimide composite subjected to water lubrication rubbing with stainless steel, functionalized mesoporous SiO 2 nanoparticles were blended into water as a new lubrication additive. Novel poly (1-(4-vinylbenzyl)-3-methylimidazolium chloride) IL was synthesized and grafted onto mesoporous SiO 2 (SiO 2 -IL) via an atom transfer radical polymerization route. It was demonstrated that SiO 2 -IL as water additives significantly reduced the friction coefficient and wear of the polyimide composite. Comprehensive analyses of the worn surfaces indicated that the grafted IL layer facilitated the formation of a protective tribofilm, separating the direct rubbing and alleviating tribo-oxidation of the steel surface. This work proposed a new route for enhancing water lubricated polymer-metal rubbing pairs.