Progress report - ESR 3: Pedro Martins Ferreira

date: May 04, 2022

category: News

Adapted organic additives for the green lubrication of polymers

The first part of the project aims to study the interactions between high-performance polymers and lubricant base oils. Pin-on-disc tests in reciprocating sliding motion under lubrication are performed to assess the tribological behavior of the polymers in self-mated contacts with different base oils. The testing matrix involves tests at room temperature, at 100°C and with aged samples. Tests are followed by a surface characterization with SEM, FTIR and wettability measurements.

Results with new samples at room temperature show that the two tested polymers when lubricated with a non-polar base oil present a higher specific wear rate compared to polar ones, even though the friction coefficient is at a comparable level or even lower. Tests performed at higher temperatures result in a higher friction coefficient compared to room temperature tests for all oils, and SEM images confirm a shift in the wear mechanism as a function of the temperature. Finally, tests with samples that have been aged show that the wear rate is greatly increased for the polar oils only.  Polar oils appear to have greater interaction with the polymer, having consequences on the chemistry of the surface and on the wear resistance. The chemical modification on the surface of aged samples was confirmed by FTIR and surface energy measurements. Future work involves further characterization of the surfaces, both chemical and mechanical characterizations, that will help explain the differences between the oils and how they interact with the polymer.