Optical Control of Microphase Separated Nanostructure in Polystyrene-Based Liquid Crystalline Diblock Copolymer Thin Film

Abstract

Develop of alignment control methods of microphase separated nanostructures in copolymers has been a subject of great demand. This paper shows the novel optical process for alignment control of nanostructures in a diblock copolymer composed of polystyrene and polymethacrylate with a liquid crystalline azobenzene-side chain. The aligned nanostructures were formed by exposure to linearly polarized light and subsequent annealing at suitable temperature. Exposure to interferometic argon ion laser beam also led to uniform alignment of nanodomains involved in a surface relief structure via photo-triggered mass migration with assist of liquid crystal.