Supramolecular Adhesion at Extremely Low Temperatures: A Combined Experimental and Theoretical Investigation.

Adhesive materials that are resistant to low temperatures have wide applications in daily life, scientific research, and industry. Currently, the overwhelming majority of low-temperature-resistant adhesives are traditional polymer systems. In this study, a new strategy was developed to obtain strong and long-lasting adhesion effects from low-molecular-weight adhesives at low temperatures. The introduction of water molecules and the formation of hydrogen bonds not only triggered supramolecular polymerization but also endowed the water-involved copolymer with low-temperature resistance. The water content of the polymeric supramolecular system played a crucial role in exhibiting adhesion behavior at low temperatures. Good adhesion performance was obtained in extremely low-temperature environments, including liquid nitrogen.

Tough, Long-Term, Water-Resistant, and Underwater Adhesion of Low-Molecular-Weight Supramolecular Adhesives.

Modern functional adhesives have attracted considerable attention due to their reversible adhesion capacities and stimuli-responsive adhesion behavior. However, for modern functional adhesives, polymeric structures were highly necessary to realize adhesion behaviors. Supramolecular adhesives from low-molecular-weight monomers were rarely recognized. Compared with polymeric adhesive materials, it remains challenging for supramolecualr adhesive materials to realize tough adhesion on wet surfaces or even under water. In this study, a new supramolecular adhesive consisting of low-molecular-weight monomers was successfully designed and prepared. Strong and long-term adhesion performance was realized on various surfaces, with a maximum adhesion strength of 4.174 MPa. This supramolecular adhesive exhibits tough and stable adhesion properties in high-moisture and underwater environments (including seawater). Long-term underwater adhesion tests display the potential application of low-molecular-weight adhesive as a marine adhesive.

Adhesion behaviour of bulk supramolecular polymers via pillar[5]arene-based molecular recognition.

Pillar[n]arenes were rarely used as the building blocks for supramolecular adhesives. Herein, pillar[5]arene-based supramolecular polymer materials with tough adhesion behaviours on different substrates were prepared, with adhesion strengths up to 4.75 MPa. Strong and long-term dichloromethane-resistant adhesion performances were successfully obtained.