Expression of chirality amplification in self-assembled achiral/chiral polyfluorene blends

Abstract

In this contribution, we report the chiroptical and morphological properties of three polyfluorenes, two chiral with different pendant groups and one achiral. Blends were prepared using different chiral/achiral ratios, and the chiroptical and morphological properties of thin films were determined, using circular dichroism spectroscopy (CD) and atomic force microscopy (AFM), respectively. The AFM height images showed the formation of self-assembled structures, associated with the achiral fraction, which was organized by the chiral component. The sergeants and soldiers principle in pristine and annealed thin films was evidenced. The morphological results are supported by chiroptic measurements. The self-assembled morphologies encompassed higher order hierarchical structures, such as helical rods and disks.