Bioinspired Superdurable Pestle-Loop Mechanical Interlocker with Tunable Peeling Force, Strong Shear Adhesion, and Low Noise.

Velcro, the most typical hook-loop interlocker, often suffers from undesirable deformation, breaking, and noise because of the structure of the hook. Inspired by the arrester system of dragonfly, a new mechanical interlocker with a nylon pestle instead of the traditional hook is developed. The pestle-loop mechanical interlocker shows a tunable peeling force from 0.4 ± 0.14 to 6.5 ± 0.72 N and the shear adhesion force of pestle-loop mechanical interlocker is about twice as much as that of velcro. The pestle tape can be separated and fastened with the loop tape up to 30 000 cycles while keeping the original adhesive force and the pestle structure. In comparison, only after 4000 cycles most hooks of the commercial velcro are deformed and even broken, completely losing their adhesive function and their hook structure. These experimental results are further supported by finite element simulitions-the base of pestle mainly bears the separation-caused strain while the middle of hook does. Notably, the sound volume during the separation of pestle-loop mechanical interlocker is merely 49 ± 7.4 dB, much lower than 70 ± 3.5 dB produced by the velcro.