COLL 352 |
| Marina Ruths, Department of Physical Chemistry, Department of Physical Chemistry, Åbo Akademi University, Porthansgatan 3-5, Åbo, FIN-20500, Finland |
| Aromatic molecules are less flexible than alkanes and have more complex intermolecular interactions, which makes their friction response interesting both from a fundamental and from a practical point of view. Friction force microscopy (FFM) and the surface forces apparatus technique (SFA) were used to study the boundary friction of single- and multicomponent self-assembled aromatic thiol and silane monolayers. The strength of the adhesion was varied by working both at dry conditions and with the surfaces immersed in a solvent. Under conditions of low adhesion, good agreement was found between friction coefficients measured with the two techniques despite the large differences in the contact areas, forces and pressures. The friction forces were generally found to be lower when both sliding surfaces were covered with a monolayer, and plateaus in the friction force as a function of velocity found in the FFM experiments appeared at higher velocity, suggesting a more fluid-like sliding. |
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Friction, Lubrication, and Adhesion in Micro- and Nano-Scale Devices
2:00 PM-5:10 PM, Tuesday, March 30, 2004 Marriott -- Orange County 5, Oral
Division of Colloid and Surface Chemistry |