Peeling from a biomimetically patterned thin elastic film

Abstract

Inspired by the observation that many naturally occurring adhesives arise as\ntextured thin films, we consider the displacement controlled peeling of a\nflexible plate from an incision-patterned thin adhesive elastic layer. We find\nthat crack initiation from an incision on the film occurs at a load much higher\nthan that required to propagate it on a smooth adhesive surface; multiple\nincisions thus cause the crack to propagate intermittently. Microscopically,\nthis mode of crack initiation and propagation in geometrically confined thin\nadhesive films is related to the nucleation of cavitation bubbles behind the\nincision which must grow and coalesce before a viable crack propagates. Our\ntheoretical analysis allows us to rationalize these experimental observations\nqualitatively and quantitatively and suggests a simple design criterion for\nincreasing the interfacial fracture toughness of adhesive films.\n