Substituent effects on fluorene-based linear supramolecular polymerizsation

Two supramolecular systems were constructed based on fluorene-based π-conjugated monomers with or without spiro structures, respectively, and their self-assemble behaviour and optical properties were investigated. Concentration-dependent ¹ H NMR and viscosity measurements indicated a transition from cyclic or oligomeric species at low concentrations to linear supramolecular polymers at high concentrations in the system without spiro structures. In contrast, the formation of cyclic species is minimised and not observed in the system with spiro structures.