Peeling in Biological and Bioinspired Adhesive Systems

Biological adhesives have inspired synthetically manufactured adhesives with novel properties. Peeling-mode failure is critical to understand these systems and achieve optimal performance. The most common models to describe peeling are briefly reviewed, followed by a literature review of all biological adhesive systems in which peeling plays a critical role, including bioinspired synthetic implementations. From this review, two systems emerge as predominantly studied in this context: gecko feet and spider silk adhesives, both of which are discussed in detail. Gecko feet represent a nanostructured adhesive that has been widely studied because of its unique reversible adhesion and self-cleaning properties. Fibrous and permanent spider silk glues used in spider webs and anchors are interesting given their capacity to withstand hurricane winds and catch and store prey.