Intense Circularly Polarized Luminescence Contributed by Helical Chirality of Monosubstituted Polyacetylenes

Introducing fluorescent chromophores to helical architectures can generate circularly polarized luminescence (CPL). Herein, a series of fluorescent chiral helical monosubstituted polyacetylenes showing both intense optical activity and CPL are prepared by copolymerizing achiral fluorescent acetylenic monomer and a chiral monomer. The luminescence dissymmetry factor ( g lum ) values of the obtained copolymers can reach up to +0.136 and −0.264. The formation of predominantly one-handed helical structures in the copolymer backbones has proved to play crucial roles in achieving the intense CPL. The dynamic helical polymer chains further enable the CPL-active materials to exhibit both solvent sensitivity and temperature sensitivity. Moreover, the helical polymer structures can also helpfully restrain the aggregation-caused quenching (ACQ) effect of fluorescent groups. Therefore, the helical polymers play double roles: providing helical chirality for generating CPL and simultaneously circumventing ACQ effect of chromophores. The present study provides new insights into designing and preparing advanced functional chiroptical materials.