Shearing of fibrillar adhesive microstructure: friction and shear-related changes in pull-off force.
To characterize the effect of shearing on function of fibrillar adhesive microstructure, friction and shear-related changes in pull-off force of a biomimetic polyvinylsiloxane mushroom-shaped fibrillar adhesive microstructure were studied. In contrast to a control flat surface, which exhibited pronounced stick-slip motion accompanied with high friction, the fibrillar microstructure demonstrated a stable and smooth sliding with a friction coefficient approximately four times lower. The structured contact also manifested zero pull-off force in a sheared state, while the flat surface exhibited highly scattered and unreliable pull-off force when affected by contact shearing. It appears that the fibrillar microstructure can be used in applications where a total attachment force should be generated in a binary on/off state and, most surprisingly, is suitable to stabilize and minimize elastomer friction.
Varenberg
M
M
Department of Thin Films and Biological Systems, Max Planck Institute for Metals Research, Heisenbergstrasse 3, Stuttgart 70569, Germany. varenberg@mf.mpg.de
Gorb
S
S
D000268:Adhesiveness; D000269:Adhesives / Q000737:chemistry*; D001696:Biomechanical Phenomena; D017276:Friction; D011145:Polyvinyls / Q000737:chemistry*; D033081:Shear Strength; D012833:Siloxanes / Q000737:chemistry*; D013499:Surface Properties
D000269:Adhesives; D011145:Polyvinyls; D012833:Siloxanes; C034183:vinyl polysiloxane