Synergistic effects of polytetrafluoroethylene fibers and graphite microplates on the tribological performance of polyetherketone composites for seawater lubrication

Abstract

Polyetherketone (PEK) is a high-performance polymer, but its composites for lubrication applications have not been well explored because of limited enhancement by one-component modification. In this study, ternary PEK composites reinforced with 5 % polytetrafluoroethylene (PTFE) fibers and different amounts of graphite (Gr) were developed. The results showed that uniform dispersion was achieved via solution blending, both PTFE and Gr exhibited good compatibility with PEK. The hardness, modulus, thermal properties of PEK composites were enhanced, together with optimal seawater wettability and absorption. Compared with PEK matrix, the friction coefficient and wear rate were reduced by 55 % and 3 orders of magnitude, respectively, at 20 % Gr loading owing to the synergetic effect between PTFE with a unique fiber topology and Gr microplates.