Supramolecular Adhesives with Extended Tolerance to Extreme Conditions via Water‐Modulated Noncovalent Interactions

Abstract

Development of supramolecular adhesives with strong tolerance to extreme conditions has emerged as an important research area. In this study, by balancing supramolecular interactions such as hydrogen bonding interactions, electrostatic interactions, π-π stacking interactions, and cation-π interactions, we designed and prepared a series of two-component supramolecular adhesives derived from small organic molecules. Highly efficient interfacial adhesion with maximum adhesion strength of � 10.0 MPa was realized on various surfaces in air, organic solvents, or liquid nitrogen. Owing to balanced supramolecular interactions, water participation prolonged and increased the tolerance of the adhesives in extreme environments. We demonstrate that the combination of imidazole-based ionic liquids and phenols can be applied for various interfacial adhesions, thereby aiding the development of next-generation adhesives capable of adapting to various extreme conditions in a controlled manner.

Small Ionic‐Liquid‐Based Molecule Drives Strong Adhesives

“…In fact, the titration experiments can also testify to the existence of cation‐π interactions in our molecular solids, excepting these calculation results. The protons on the imidazole ring and vinyl group showed a constant high‐field shift with the addition of 4‐(trifluoromethyl)phenylisocyanate, which could be attributed to cation‐π interactions (Figure S40) [8b,13a] . In addition, π–π and dipole–dipole interactions have been extensively studied in many supramolecular systems [25] .…”

Solvent-Free and Recyclable Polyether/Polyphenol Supramolecular Adhesives with Robust, Water- and Low-Temperature-Resistant Properties

“…Supramolecular self-assembly presents a promising solution to overcome the aforementioned problems. Supramolecular adhesives (SAs) are formed based on polymers or small molecules through dynamic noncovalent interactions, including hydrogen bonding, cation-π, host–guest, and π–π stacking. − Thanks to their inherent reversibility and dynamic responsiveness, SAs are expected to achieve efficient recycling through external stimuli such as light, heat, magnetism, electricity, and ultrasound. − In the majority of cases, SAs are still unable to avoid using solvents. Nevertheless, the evaporation and removal of solvents during application not only diminish their recoverability and reusability but also undermine the stability of dynamic noncovalent interactions, thus significantly impacting adhesion and processing properties. − Researchers have been dedicated to the development of solvent-free SAs to avoid the use of solvents.…”

Biocompatible Tough Ionogels with Reversible Supramolecular Adhesion

“…Therefore, achieving both high strength and high adhesion strength of ionogels remains a great challenge. Existing gel adhesives typically achieve high adhesion strength by sacrificing their own mechanical properties and cannot avoid fatigue damage during use. − In addition, reuse and recycling of ionogels are necessary, and reversible adhesives with high adhesion strength hold great promise for practical application. − However, most of the existing reversible adhesives suffer from low adhesion strength or complicated manufacturing processes.…”