Peeling-Induced Rolling and Heterogeneous Adhesion in Blistered Films

TL;DR

This study uncovers a novel peel-to-roll transition in blistered thin films on soft substrates, revealing how interfacial interactions and contact morphology lead to spatially tunable, heterogeneous adhesion with potential for reconfigurable surface applications.

Contribution

The paper demonstrates a new peel response mechanism involving spontaneous rolling and contact edge interactions, supported by experiments, scaling analysis, and molecular dynamics simulations.

Findings

Peel-to-roll transition causes a sharp adhesion force drop.

Contact length at transition is independent of work of adhesion.

Rolling induces spatial variations in adhesion force.

Abstract

Blisters, delaminated regions that form in multilayered structures under compressive stresses, are observed across a wide range of length scales, from two-dimensional materials to protective coatings and laminated composites. Far from being passive defects, such interfacial features have emerged as functional motifs for three-dimensional architectures and reconfigurable surfaces. Here we reveal an unusual peel response of a blistered thin film on a soft substrate. When peeled from one end, the advancing peel front triggers reattachment at the blister edge once a critical separation is reached, initiating spontaneous rolling of the film on the substrate. This peel-to-roll transition produces a sharp drop in the measured adhesion force, which then remains constant throughout the rolling phase. Using experiments, scaling analysis, and molecular dynamics simulations, we resolve the contact morphology at the transition and identify the contact length at which rolling initiates. We show that this length arises from interactions between the two contact edges and is independent of the work of adhesion. Once rolling begins, a dynamically imposed dwell time - defined by the rolling length and peel speed - translates contact history into spatial variations in adhesion force, thereby governing the magnitude of the force drop. Together, these results point to a new pathway for generating spatially tunable, heterogeneous adhesion from otherwise homogeneous interfaces.