Supramolecular Zwitterionic Polymers: Dynamic Traits Imparted by Ionic Interactions

Supramolecular ionic polymers (SIPs) exhibit distinctive dynamic properties, which arise from the synergistic combination of substantial strength and pronounced reversibility of ionic interactions. However, conventional SIPs formed by coassembly using anionic and cationic separated double monomers suffer from complicated synthesis and heterogeneous structures, which obscure in-depth investigation of their dynamic behaviors. In response, we developed a zwitterionic monomer, namely TPE-2N2S, that incorporates both charged motifs into one fluorescent tetraphenylethylene (TPE) skeleton. This zwitterionic and single-component monomer design strategy enables the efficient formation of supramolecular zwitterionic polymers (SZIPs) with a uniform and orderly structure, and it can further enhance the understanding of structure-property relationships. In this perspective, we examine the dynamic features of ionic interactions in SZIPs, emphasizing their structural advantages, controllable assembly, and ionic interaction characteristics. We further investigate the dynamic behavior driven by ionic interactions at the intramolecular, intermolecular, and supramolecular architecture levels. Finally, we discuss key challenges and future opportunities in this emerging field, aiming to advance the design and application of SZIPs.