Unraveling the Dynamic Helicity Inversion and Chirality Transfer by the Iterative Exponential Growth Synthesis of Azobenzene Discrete Oligomers

Unraveling the chirality transfer mechanism of polymer assemblies and controlling their handedness is beneficial to exploring the origin of hierarchical chirality and developing smart materials with desired chiroptical activities. However, polydisperse polymers often lead to an ambiguous or statistical evaluation of the structure‐property relationship, it remains unclear how the iterative number of repeating units can function in the helicity inversion of polymer assemblies. Herein, we report the macroscopic helicity and dynamic manipulation of the chiroptical activity of supramolecular assemblies from discrete azobenzene‐containing oligomers (Azooligomers), together with the helicity inversion and morphological transition achieved solely by changing the iterative chain lengths. The chiral supramolecular assemblies of the iterative Azooligomers were collectively characterized by CD, UV‐vis, small‐angle X‐ray scattering (SAXS), and wide‐angle X‐ray diffraction (WAXD) spectroscopy, transmission electron microscopy (TEM), and ultrasonic uncoiling experiments, revealing that their helicity inversions are governed by distinct stacking modes and delicate balance of kinetics and thermodynamics. The corresponding assemblies also differ from their polydisperse counterparts in terms of thermodynamic properties, chiroptical activities, and morphological control.