Preparation and tribological performance of perfluoropolyether derived coatings

A series of perfluoropolyether (PFPE) functional derivatives terminated with different amide groups (FD-As) were synthesized. The chemical structures of the FD-As were determined by FTIR, 1H and 19F NMR spectra, and the thermo stability was determined by TG analysis. Thin films of FD-As were fabricated by strongly adsorbing FD-As molecules on the surfaces of metals such as aluminum plates and steel balls. The thin films of FD-As prepared possessed very low surface free energy about 12 mN/m. Tribological performance of these thin films was characterized using a UMT-2 model micro-tribometer and a four-ball tribotester using paraffin liquid as lubricant. Thin films of FD-As at both states of UMT and four-ball tribo analysis can reduce the friction coefficient. And the anti-wear property of the liquid lubricant can also be improved.