Self Forming Spatular Structures
As a model for self-forming spatular structures we have fabricated model core-shell fibrils by coating an aluminum wire with (poly)dimethylsiloxane.
( a) Optical micrograph of a terminal shell fabricated by a coating an aluminum wire by PDMS and partially etching the wire. (b) Scanning electron micrograph of a coated, partially etched, and trimmed sample with shell thickness of about 25 microns.
Schematic drawing of set-up to test adhesion under shear. The fibril is preloaded in the vertical direction upto a fixed displacement before being dragged horizontally.
Initial contact of the shell with the substrate increases with increasing displacement.
Shear force increases with increasing initial displacement. Dragging is accomodated by stick-slip.
(Matt Havener, Vince Sica, T. Tang)