Tetragonally and Rectangularly Packed Hierarchical Cylinders from A₁BA₂C Tetrablock Terpolymer

Abstract

Hierarchical cylindrical nanostructures with different diameters (or shapes) have received much attention because of potential applications to next‐generation lithography or advanced optical devices. Herein, via small‐angle X‐ray scattering and transmission electron microscopy, tetragonally and rectangularly packed hierachical cylindrical nanostructures are observed by tailoring the volume fraction of polystyrene mid‐block in polystyrene‐b‐polyisoprene‐b‐polystyrene‐b‐poly(2‐vinylpyridine) tetrablock terpolymer (S1IS2V). P2VP becomes the main cylinder, while PI forms satellite cylinders surrounding the main P2VP cylinder. When the length of S2 block is relatively short, tetragonal arrangement of cylinders is observed. But, a rectangular arrangement of cylinders is formed for larger S2 block. The experimentally observed hierarchical cylindrical nanostructures are in good agreement with the prediction by the self‐consistent field theory.