Figure 6.

Finite-element simulation of sequential attachment of contacting sites as a thin film is dragged along a substrate at a very low angle. (a) Schematic of the simulation process. At stage I, the film adheres to the first contacting site on the left under near 0° dragging. Right before it begins to detach from the substrate, the detached part of the film becomes attached to the second contacting site. (b) The simulated force–displacement relationship for the sequentially attached film. The film now has a built-in pre-tension and the peel-off force of 0.8 nN nm⁻¹ is about twice that predicted from Kendall's model in the absence of pre-tension.