Inspired by the fascinating adhesive and cold-tolerant properties, Chinese researchers have recently proposed a spider-silk-inspired wet adhesive. The adhesive composed of core–sheath nanostructured fibers with hygroscopic adhesive nanosheath and supporting nanocore, showing robust wet adhesion and supercold tolerance. 

The study, published in Advanced Materials, was directed by Prof. WANG Shutao's team from the Technical Institute of Physics and Chemistry (TIPC) of the Chinese Academy of Sciences (CAS). And the work has demonstrated the promising applicability of this spider-silk-inspired adhesives in cryogenic environments. It also provide an innovative route to design functional wet adhesives.  

With the development of human society, the adhesive materials are now applying in various fields and facing more complex environments like polar adventure, aerospace and cold supply chain. However, achieving or maintaining high adhesion performance in complex environments remains a major challenge for the developed adhesives.  

Scientists observed that spiders can capture prey under the roof or along the lake with their capture silks. Besides, the dragline silks of spider exhibit high mechanical property at very low temperature. With the inspiration of spider, Prof. WANG et al. designed their work.  

It is found that the adhesion performance of this spider-silk-inspired adhesive could be optimized by regulating the water content, the wettability of the adhered surface and the diameter of supporting nanocores.   

To further demonstrate the promising applicability of the wet adhesive in cryogenic environments, the researchers adhered this spider-silk-inspired adhesive on different objects, such as fresh apple, frozen meat package, cryo-tube, and even metal box with cryopreserved cells and stored them in their corresponding store temperature. As a result, it maintained reliable adhesion in their corresponding store temperature (from 4 to -196 °C) and further tolerated disturbances in liquid nitrogen (-196 °C). 

According to Prof. WANG, the study may provide a new design principle to fabricate functional adhesives to meet requirements of extreme environments, and also promote developing in spider-silk-inspired materials and other new wet adhesive materials. 

This work is supported by the National Key R&D Program, the National Natural Science Foundation of China, and the National Program for Special Support of Eminent Professionals of Organization Department of the CPC Central Committee. 

Figure. Spider-Silk- Inspired Wet Adhesive Demonstrates Universal Wet Adhesion with Supercold Tolerance. (Image by WANG et al.)

https://doi.org/10.1002/adma.202007301