Multidomain Helical Nanostructure by A1BA2C Tetrablock Terpolymer Self-Assembly

Among many possible nanostructures in block copolymer self-assembly, helical nanostructures are particularly important because of potential applications for heterogeneous catalysts and plasmonic materials. In this work, we investigated, via small-angle X-ray scattering and transmission electron microscopy, the morphology of a polystyrene-block-polyisoprene-block-polystyrene-block-poly(2-vinylpyridine) (S1IS2V) tetra-block terpolymer. Very interestingly, when the volume fraction of each block was 0.685, 0.125, 0.060, and 0.130, respectively, a multidomain double-stranded helical nanostructure (MH2) was formed: P2VP chains became a core helix, and PI chains formed double-stranded helices surrounding the core helix. Core and double-stranded helices are connected by short PS2 chains, and PS1 chains become the matrix. The experimentally observed morphology is in good agreement with the prediction by self-consistent field theory. We believe that this multidomain helical structure will be pave the way to the creation of multifunctional helical structures for various applications such as metamaterials.

Automated summary

This study investigated the formation of a multidomain double-stranded helical nanostructure, paving the way for the creation of multifunctional helical structures for various applications such as metamaterials. The experimentally observed morphology matched well with the prediction by self-consistent field theory.