Polymer Brushes for Silicon Nitride-Steel Contacts: a Colloidal Force Microscopy Study

摘要

1. Polymer brushes have been successfully formed on silicon nitride and tribologically tested for the first time. 2. Controlled ARGET ATRP can form up to 37 nm thick PMMA in 150 minutes, confirmed by contact angle, XPS and ellipsometry measurements. © XPS analysis shows the polymers are well-defined and retain end group functionality Further XPS core spectra show carbon and oxygen elements exist in different bonding forms and their contributions into each elemental signal are in expected ratios as in PMMA stoichiometry 3. Nanotnbological tests with colloidal probes accurately demonstrated the impact of the polymer film within a hybrid contact under simulated machinery operational conditions for the first time. 4. Tribological testing in PAO results in a solvated brush system resulting in reduced friction forces indicating the importance of a synergistic solvent Swelling effects are clearly related to frictional response 5. Friction can be reduced within the hybrid contact between two and a half to three and a half times by using PMMA polymer brushes.