A Spider‐Silk‐Inspired Wet Adhesive with Supercold Tolerance

Abstract

Conventional adhesives often encounter interfacial failure in humid conditions due to small droplets of water condensed on surface, but spider silks can capture prey in such environment. Here a robust spider‐silk‐inspired wet adhesive (SA) composed of core–sheath nanostructured fibers with hygroscopic adhesive nanosheath (poly(vinylpyrrolidone)) and supporting nanocore (polyurethane) is reported. The wet adhesion of the SA is achieved by a unique dissolving–wetting–adhering process of core–sheath nanostructured fibers, revealed by in situ observations at macro‐ and microscales. Further, the SA maintains reliable adhesion on wet and cold substrates from 4 to −196 °C and even tolerates splashing, violent shaking, and weight loading in liquid nitrogen (−196 °C), showing promising applicability in cryogenic environments. This study will provide an innovative route to design functional wet adhesives.

Development of a multifunctional nanocomposite film with record-high ultralow temperature toughness and unprecedented fatigue-resistance

“…Unlike the mineralized natural materials (biological bone), both the structural unit (β-sheets nanocrystals) and "soft part" (semiamorphous matrix) of spider silk consist of protein, highlighting a key role of orderly hierarchical architecture (β-sheets nanocrystals and H-bonds) 16 . Recently, many other fascinating properties of spider silks were gradually disclosed, such as vibration propagation, rubber-like elasticity, shape memory, and water collection 22 . However, the ultralow temperature performance of spider silks was barely concerned probably.…”

Permeable Conductors for Wearable and On‐Skin Electronics

“…Therefore, further optimization of electrode and device structures is required to balance their adhesion properties and functionalities. [ 85 ] Alternatively, one possible development avenue is the use of hydrogel, which has attracted great attention as a means of enhancing the adhesion of electrodes due to their biocompatible and viscoelastic features as discussed previously. Via tuning the structures and material compositions, they could serve as the soft and conformable adhesive layers for flexible and stretchable electronics without affecting their breathability to gas and liquid, preventing damage to human skin and ensuring the steady use of on‐skin electronics.…”

Emerging Biopolymer‐Based Bioadhesives

“…[ 87 ] Spiders in nature capture prey using unique adhesive silks that accommodate dry to wet conditions. [ 88 ] They may have developed a temperature or humidity‐sensitive sensor for the best of the sticky web. Mussels develop a synergistic adhesion mechanism involving noncovalent and covalent chemical interactions, providing strong adhesion to various surfaces.…”