Preparation of polyimide-graphite composite and evaluation of its friction behavior at elevated temperatures

Abstract

In this paper, polyimide-graphite (PG) composite was prepared and used as a solid lubricant at elevated temperatures. PG composite was characterized by X-ray diffraction, and its thermal stability was evaluated based on thermogravimetric/differential thermal analysis and Fourier transform infrared spectrometry analysis. The results show that in PG composite, there was some interaction between the graphite (GR) and the polyimide (PI) matrix. Consequently, the PG composite exhibited better thermal stability than PI. The friction behavior of the PG composite sliding against steel at elevated temperatures (300-600°C at an interval of 100°C) was evaluated with a ring-on-ring tribometer. It was found that the PG composite exhibited excellent friction-reducing ability and good load-carrying capacity in the temperature range of 300-600°C and applied loads of 300-700 N. Moreover, this excellent lubricating performance of the PG composite might be attributed to its good thermal stability as a result of the interaction between the GR and the PI matrix. Therefore, PG composite could be used as an excellent solid lubricant under the high-temperature conditions.

Friction and wear behavior of polyimide matrix composites filled with nanographite

“…A plausible explanation for this might be that an interaction between the NG and PI matrix occurs because NG is a layered material bonded by van der Waals interactions between carbon sheets that can be doped by polymer chains between those carbon sheets. 20 These results suggest that the enhancement of thermal stability could reduce the effect of thermal softening allowing these composites to potentially have tribological applications due to the low thermal conductivity of polymeric materials.…”