Photo-actuated bending of chromatic liquid crystal polymer strips and laminates

Abstract

Photochromic liquid crystal polymer (LCP) films can undergo spontaneous mechanical deformations upon light illuminations. The light-induced strain is due to photoisomerization and the nematic-isotropic phase transition. A gradient strain exists due to absorption decay of the light intensity and will produce bending of LCP strips. Beam bending models are studied for single layered and bilayered LCP strips with substrate. The results show that the multilayered structures can have much larger bending curvature due to the utilization of the average light-induced contractions which were mostly not active for single-layered LCPs. Some structural optimizations for bilayered laminate are also discussed. © 2011 Copyright Taylor and Francis Group, LLC.