Strong and Reversible Adhesion of Interlocked 3D-Microarchitectures

Abstract

Diverse physical interlocking devices have recently been developed based on one-dimensional (1D), high-aspect-ratio inorganic and organic nanomaterials. Although these 1D nanomaterial-based interlocking devices can provide reliable and repeatable shear adhesion, their adhesion in the normal direction is typically very weak. In addition, the high-aspect-ratio, slender structures are mechanically less durable. In this study, we demonstrate a highly flexible and robust interlocking system that exhibits strong and reversible adhesion based on physical interlocking between three-dimensional (3D) microscale architectures. The 3D microstructures have protruding tips on their cylindrical stems, which enable tight mechanical binding between the microstructures. Based on the unique 3D architectures, the interlocking adhesives exhibit remarkable adhesion strengths in both the normal and shear directions. In addition, their adhesion is highly reversible due to the robust mechanical and structural stability of the microstructures. An analytical model is proposed to explain the measured adhesion behavior, which is in good agreement with the experimental results.

Recent progress in polymer hydrogel bioadhesives

“…41 Once in contact with water, the hydrogel adhesive underwent nano/micro and macro shape reconstruction, which shut down the adhesive (≈0.30 kPa) with an extremely high adhesive conversion rate (> 640). Jeong et al 42 also developed a highly flexible and sturdy reversible interlocking adhesive based on a threedimensional (3D) microarchitecture with protruding tips on its cylinder stem. By integrating various functional nanomaterials into the microstructure, this reversible interlocking adhesive helps the development of advanced flexible electronic, mechanical, and biomedical devices.…”

Bioinspired Multiscale Wet Adhesive Surfaces: Structures and Controlled Adhesion

“…For instance, poly(ethylene glycol) dimethacrylate microhooks show greatly enhanced wet adhesion between two layer of microhooks due to shape‐reconfigurable triggered by water . Later, poly(urethane acrylate) (PUA) microhooks form a robust mechanical interlocking system, exhibiting strong and reversible adhesion taking advantage of physical interlocking . Besides, bioinspired seta array (i.e., microneedles4e or microcilia) with the functions of tissue adhesion and transportation of microscale objects, are fabricated by duplicating from a mold with conical holes.…”

Hooked on mushrooms: Preparation and mechanics of a bioinspired soft probabilistic fastener

“…Conventional lithography techniques are known for being able to create microscopic patterned surfaces in soft elastomers, indeed with high resolution, including complex 3D structure such as mushrooms having a flat disk shape hat [15][16][17][18]. Realizing micrometric mushroom features having spherical-like shapes such as "3M dual lock" or a half-spherical hat that is essential for mechanical interlocking has not been possible below a millimeter scale.…”