Multi-stimuli-responsive supramolecular polymer via orthogonal pillararene-based host-guest and π- π interactions

We designed and prepared a supramolecular assembly-induced emission enhancement supramolecular polymer (PyP5 subset of S2NH2) via rational combination host-guest and pi- pi stacking interactions between pyrenefunctionalized pillar[5]arene host (PyP5) and the bis(dialkylammonium salt)-based BB type guest (S2NH2). With the increasing concentration of S2NH2 and PyP5, the structures of PyP5 subset of S2NH2 transformed from linear to cross-linked networks. Moreover, PyP5 subset of S2NH2 can be sensitive to multiple stimuli, including temperature, redox, UV-light, pH, solvent polarity, organometallic compound, and competitive guest. This work paves the way to develop fluorescent supramolecular polymers with multi-stimuli-responsive properties via facilely supramolecular approaches.