The Tribological Behavior of Blends of Polyetheretherketone (PEEK) and Polyetherimide (PEI) at Elevated Temperatures

The friction and wear under dry sliding conditions of injection molded blends of Polyetheretherketone (PEEK) and Polyetherimide (PEI) at temperatures from 20°C to 232°C were investigated on a pin-on-disk apparatus. The friction and wear results were correlated to results obtained from dynamic mechanical thermal analysis (DMTA) temperature scans performed on each of the materials. It was found that tan δ peaks corresponding to α transitions occurring in the vicinity of the glass transition temperature (Tg) coincided with catastrophic tribological failure in the case of PEI and the amorphous PEEK/PEI blends. PEEK and the annealed 70% PEEK/30% PEI blend, exhibited marked increases in friction and wear at and above the Tg. The absence of catastrophic tribological failure in PEEK and the annealed 70/30 blend in the vicinity of the glass transition temperature corresponded to a transitions of significantly lesser strength (i.e. lower tan δ peak values) than those observed in PEI and the amorphous blends. Betwee...