Characterization and Tribological Performance of Polyethersulfone/PTFE Compound Filled with Na-Montmorillonite

Lamellar sodium-montmorillonite (NaMMT) was used as reinforcing filler to improve the abrasion resistance of polyethersulfone (PES)/polytetrafluoroethylene (PTFE)-based polymers. As filler, the interlayer distance of NaMMT was decreased from 1.523 to 0.995 nm, resulting from the evaporation of interlayer water during the heat treating of composites. The abrasion resistance of PES/PTFE-based composite was effectively improved by introducing NaMMT, attributing to the load bearing of NaMMT on the worn surface. The polymer sample with 20 wt% NaMMT exhibited the best anti-wear performance, which is ascribed to its densification worn morphology. In addition, unlike the pure PTFE transfer films formed for the PTFE and PES/PTFE compounds, NaMMT is also involved in the PTFE transfer film of NaMMT/PES/PTFE compounds. It is inferred that the self-lubricating property of PTFE transfer film is destroyed because of the introduction of NaMMT, leading to that the friction coefficient of NaMMT/PES/PTFE compounds was a little larger than those of PTFE and PES/PTFE compounds.