Cohesive Zone Smoothing of Bending Stiffness Heterogeneities in Tape Peeling Experiments

This work studies the interaction between the cohesive zone and elastic stiffness heterogeneity in the peeling of an adhesive tape from a rigid substrate. It is understood that elastic stiffness heterogeneities can greatly enhance the adhesion of a tape without changing the properties of the interface. However, in experiments performed on adhesive tapes with both an elastic stiffness heterogeneity and a substantial cohesive zone, muted adhesion enhancement was observed. It is proposed that the cohesive zone acts to smooth out the effect of the discontinuity at the edge of the elastic stiffness heterogeneities, suppressing their effect on adhesion. This work presents peel tests performed with heterogeneously layered 3 M 810 tape that demonstrate the muted enhancement. Additionally, numerical simulations further investigating the interaction between elastic heterogeneity and cohesive zone are presented.