Asymmetric Living Supramolecular Polymerization: Precise Fabrication of One-Handed Helical Supramolecular Polymers.

Abstract

Programming the organization of semiconducting polymers to form well-defined nanoarchitectures is desirable for fabricating functional materials. In this work, semiconducting copolymers, poly(cholesterol allene)-b-poly(3-hexylthiophene) (PCA-b-P3HT) containing helical PCA and poly(alkoxy allene)-b-poly(3-hexylthiophene) (PAA-b-P3HT) containing achiral PAA segments, were prepared. Crystallization of P3HT and helicity of PCA drove PCA-b-P3HT self-assemble into spherical nanoparticles that gradually transformed into one-handed helical nanofibers. The chirality of PCA was transferred to the supramolecular architectures, induced high optical activity in P3HT. Interestingly, the chiral seed micelles of PCA-b-P3HT induced asymmetric copolymerization of achiral PAA-b-P3HT, which led to helical supramolecular block copolymers with defined helicity and controlled length. Remarkably, the supramolecular copolymers showed white-light emission and circularly polarized luminescence.