Functionalization of carbon nanotubes to improve the tribological properties of poly(furfuryl alcohol) composite coatings

The functionalization of multi-walled carbon nanotubes (MWNTs) was achieved by grafting furfuryl alcohol (FA) onto surfaces of the MWNTs. The functional MWNTs were examined by infrared spectroscopy, thermal gravimetric analysis, X-ray photoelectron spectroscopy. Furthermore, the functional MWNTs were incorporated into the poly(furfuryl alcohol) (PFA) resin and the tribological behaviors of resultant PFA composite coatings were investigated using a ring-on-block wear tester under dry friction condition, and the worn surfaces were studied by scanning electron microscopy. The dispersion of MWNTs in PFA composites was examined using field emission scanning electron microscope. The results indicated that an esterification was formed in the acylating MWNTs and FA, and the functionalization led to an improvement in the dispersion of MWNTs and the tribological properties of PFA composite coatings.