Towards a Unified Model of Soft Adhesives

Pressure Sensitive Adhesives (PSA) have been widely used in adhesive tapes, stickers, tags in industry and day-to-day use, for decades. PSAs are rate-dependent materials, extremely soft, hence highly deformable. Their bonding strength depends critically on small scale features such the surface properties of the substrates. Understanding quantitatively their behavior has been a enormous challenge. Quite surprisingly, a same adhesive can be described by different models with little connection within each other depending on the adhesion tests used. In this talk, I will present a new modeling strategy to these soft materials [Creton and Ciccotti, Soft Matter, (2016)] based on the identification of the mesoscale mechanisms (cavitation, fibrillation, ...) along with the evaluation of the contribution of the large strain rheology of the PSA into the total work of debonding. I will discuss some original experimental investigations providing insights into the pertinent links between the peel, tack and shear of model PSAs.