Multiple Stimuli-Responsive Supramolecular Hydrogels Constructed by Decamethylcucurbit[5]uril-para-phenylenediamine Exclusion Complex

Macromol Rapid Commun. 2021 Sep 4;e2100431. doi: 10.1002/marc.202100431. Online ahead of print.

Abstract

The hydrogels composed of decamethylcucurbit[5]uril (Me10 Q[5]) and para-phenylenediamine (p-PDA) are first reported herein. They are the first Q[5]-based supramolecular hydrogels, the formation of which is driven by portal exclusion between Me10 Q[5] and p-PDA. The composition, structure, and properties of the Me10 Q[5]/p-PDA-based hydrogels are investigated by various techniques. Since the 1D supramolecular chain forms via portal exclusion between Me10 Q[5] and p-PDA is the key to the formation of the hydrogels, any competitive species, such as metal ions, organic molecules, and amino acids, which can affect the portal exclusion, can change the behavior of the Me10 Q[5]/p-PDA-based hydrogels. Hence, the hydrogels can be used for various applications. Importantly, the results may provide a new research direction for the preparation of Q[n]-based hydrogels via portal exclusion of Q[n]s with guests.

Keywords: decamethylcucurbit[5]uril; exclusion complexes; hydrogel response; para-phenylenediamine.