Effect of the addition of room temperature ionic liquid and ZnO nanoparticles on the wear and scratch resistance of epoxy resin

New dispersions of the ionic liquid (IL) 1-octyl-3-methylimidazolium tetrafluoroborate ([OMIM]BF4) and ZnO nanoparticles in epoxy resin (RE) have been prepared and characterized by SEM and TEM, and their thermal and dynamic mechanical properties have been determined. The presence of ZnO nanoparticles increases the stiffness of the epoxy resin, while the addition of the IL phase enhances chain mobility and produces a plasticizing effect. In order to evaluate the effect of the additives on the adhesive and abrasive wear of the epoxy resin, the tribological performance of the new dispersions has been studied in pin-on-disc sliding tests and multiscratch tests, respectively. The results are a function of sliding conditions. Under the pin-on-disc configuration, the addition of IL reduces the friction coefficient in a 50% and the wear rate in two orders of magnitude, due to the IL lubricant effect. Under multiscratching conditions, only the addition of ZnO reduces the residual depth of the scratch groove on the epoxy resin after viscoelastic recovery. Results are discussed from SEM and TEM observations, EDS analysis and three-dimensional surface profiles.