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arXiv · 2107.09367

Transition from viscoelastic to fracture-like peeling of pressure-sensitive adhesives

Marion Grzelka·Stefan Kooij·Sander Woutersen·Mokhtar Adda-Bedia·Daniel Bonn
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Abstract

We investigate the process of the slow unrolling of a roll of typical pressure-sensitive adhesive, Scotch tape, under its own weight. Probing the peeling velocities down to nm/s resolution, which is three orders of magnitudes lower than earlier measurements, we find that the speed is still non-zero. Moreover, the velocity is correlated to the relative humidity. A humidity increase leads to water uptake, making the adhesive weaker and easier to peel. At very low humidity, the adhesive becomes so stiff that it mainly responds elastically, leading to a peeling process akin to interfacial fracture. We provide a quantitative understanding of the peeling velocity in the two regimes.

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Marion Grzelka, Stefan Kooij, Sander Woutersen, Mokhtar Adda-Bedia, Daniel Bonn. 2021-07-20. Transition from viscoelastic to fracture-like peeling of pressure-sensitive adhesives. https://doi.org/10.1039/d1sm01270c

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