Abstract
The isomerization of pendant groups plays a crucial role in modulating helical structures and biological activity in both biomacromolecule and dynamic helical conjugated polymers. While the effects of solvents, pH, and temperature on pendant isomerization and helix preference have been extensively studied, the combined influence of pendant isomerization and enantiomeric excess remains largely unexplored. Herein, we report a dynamic helical poly-(phenylacetylene) (PPA) system, poly-[D (r) -co-L ((1-r))], in which the helix preference is dictated and nonlinearly amplified via the "majority rule" mechanism at low temperatures. Remarkably, temperature-triggered pendant isomerization can override this helix preference, leading to an "abnormal majority rule" behavior. By harnessing these dual effects, precise helix regulation is achieved, enabling helix inversion at high enantiomeric excess and chiral sustenance at low enantiomeric excess. A bifurcation point in helix preference facilitates the orthogonal control of polymer helicity, paving the way for programmable circularly polarized luminescence microarrays, with potential applications in information encoding and anticounterfeiting technologies. These findings provide a strategy for fine-tuning dynamic helical polymer structures.