Stability of tunnel structure and relationship between peel load and spatiotemporal pattern by deformed adhesive during peeling

We investigated (i) the relationship between the spatiotemporal pattern of a deformed adhesive and peel load during peeling, and (ii) the dependence of the pattern formation on peel speed in the hard spring limit case. In the hard spring limit case, it is found that elastic and viscous peeling states coexist. It is also found that the occupation ratio of tunnel structures in a separation front is determined by the peel speed and is a monotonically decreasing function of peel speed. We experimentally confirmed that the value of peel load has a linear dependence on the occupation ratio of tunnel structures. An explanation of dynamical behavior is also given on the basis of the creation-annihilation dynamics of tunnel structures.