  We study the peeling process of a thin viscoelastic tape from a rigid
substrate. Two different boundary conditions are considered at the interface
between the tape and the substrate: stuck adhesion, and relative sliding in the
presence of frictional shear stress. In the case of perfectly sticking
interfaces, we found that the viscoelastic peeling behavior resembles the
classical Kendall behavior of elastic tapes, with the elastic modulus given by
the tape high-frequency viscoelastic modulus. Including the effect of
frictional sliding, which occurs at the interface adjacent to the peeling
front, makes the peeling behavior strongly dependent on the peeling velocity.
Also, at sufficiently small peeling angles, we predict a tougher peeling
behavior than the classical stuck cases. This phenomenon is in agreement with
recent experimental evidences indicating that several biological systems (e.g.
geckos, spiders) exploit low-angle peeling to control attachment force and
locomotion.
