Photomechanical energy conversion based on cross-linked liquid-crystalline polymers

Abstract

Cross-linked liquid-crystalline (LC) polymers with a photochromic moiety show photoinduced deformation with change in molecular shape and alignment of photochromic compounds. Molecular-level photoisomerization of the photochromic moieties can give rise to macroscopic deformation of the materials, allowing one to convert light energy directly into mechanical work. The photomechanical effects extend the applicability of azobenzene-containing polymers towards light-driven actuators and artificial muscles. Recently, the effect of structure–property relationships and crosslinking density on the photomechanical property of photochromic polymers was investigated. Various motions based on the photoinduced deformation of the LC polymers were achieved by forming the polymer materials. This chapter summarizes the recent progress in photoinduced movements and light-driven actuation property of the LC polymers, in particular cross-linked LC polymers with a photochromic property.