Polystyrene-block-polyisocyanide copolymer: from polymerization-induced chiral self-assembly to circularly polarized light emission and enantiomer separation

Abstract

The precise construction of chiral supramolecular assemblies remains a significant challenge in the field of helical polymers. In this work, we successfully synthesized polystyrene-block-polyisocyanides copolymers via one-pot sequential living polymerization using alkynyl-Pd(II) as the catalyst. The block copolymerization induced chiral self-assembly simultaneously due to the one-handed helicity of the polyisocyanides block, giving spherical nanoparticles, one-handed helices, and chiral micelles with controlled dimensions regarding the composition of the generated copolymers. Interestingly, the chiral assemblies exhibit clear circularly polarized luminescence with tunable handedness and a high dissymmetric factor. Moreover, the block copolymer could be processed into membranes for enantiomer separation applications. Remarkably, these membranes effectively separated the enantiomers of racemic 2-phenyl-1-propanol, achieving 96% enantiomeric excess (ee).