Friction of Self-Assembled, Polyaromatic Monolayers M. Ruths, Department of Chemistry, University of Massachusetts Lowell, MA 01854
⇒ Non-linear F vs. L in adhesive contacts can be investigated by taking the size of the contact area into account. A contact mechanics model (SJF) for a compliant elastic film and a spherical probe can be applied. • Higher packing density => lower friction in these systems. • At high loads, transitions occur in the self-assembled monolayers, causing a different friction response.
Friction force, F (nN)
• Aromatic and polyaromatic compounds: natural lubricants in mineral oils and fuel.
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Thiophenol-modified gold surface in dry N2 gas. AFM tip R = 52 nm.
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Load, L (nN)
Friction Force, F (nN)
• Fundamental aspects of friction and its dependence on the strength of adhesion
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2-Napthalenethiol-modified gold surface in dry N2 gas. AFM tip R = 103 nm.
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Load, L (nN)
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