ON ADHESIVE THEORIES IN MULTILAYERED INTERFACES, WITH PARTICULAR REGARD TO "SURFACE FORCE APPARATUS" GEOMETRY

Adhesion is a key factor in many tribological processes, especially wear. We generalize a recent formulation for the indentation of a multilayered material using an efficient integral transform method, to the case of adhesion, using a simple energetic transformation in the JKR regime. Then, we specialize the study for the geometry of the Surface Force Apparatus, which consists of two thin layers on a substrate, where the intermediate layer is softer than the other two. We find the pull-off force under "force control" (i.e. for "soft" loading systems), as well as under "displacement control" (i.e. for "rigid" systems), as a function of the geometrical thicknesses and material properties ratios, and the method is fully implemented in a fast Mathematica code, available to the public (see Appendix).

Direct measurements of structural forces and twist transitions in cholesteric liquid crystal films with a surface force apparatus

Mechanical micro-confinement of a cholesteric liquid crystal between crossed cylinders produces dislocations, twist transitions and oscillatory structural forces.

Probing molecular interactions of PEGylated chitosan in aqueous solutions using a surface force apparatus

The effects of contact time, solution pH and PEGylation degree on the non-covalent interaction behavior of chitosan are systematically investigated.

Nano-mechanics of ionic liquids at dielectric and metallic interfaces

Using a dynamic surface force apparatus, we investigate the nano-mechanics and the nano-rheology of an ionic liquid at dielectric and metallic solid surfaces.