Tribological performance of polydopamine plus Ag nanoparticles/PTFE thin films

This study aims to improve the polytetrafluoroethylene (PTFE) thin film adhesion to stainless steel substrates by incorporating Ag nanoparticles (AgNPs) in a polydopamine (PDA) underlayer. Three different weight percent (1.0 wt%, 1.5 wt%, and 2.0 wt%) of AgNPs were added to the PDA deposition solution, resulting in an increased underlayer roughness. A 3.6-time increase in durability was achieved by adding only 2.0 wt% of AgNPs. Scratch and wear tests demonstrated the improved adhesion and wear resistance of the PDA + AgNPs/PTFE thin films. The improvement was attributed to the increased underlayer roughness, denser fibrillar PTFE network, and enhanced film transfer, all brought by the AgNPs.