Thermal deformation of imprinted twist nematic elastomers

Abstract

A nematic elastomer film with a 90° twist orientation between the top and bottom surfaces is prepared by chiral imprinting methods. The reactive achiral nematic monomers and crosslinkers are photopolymerized in the presence of a controlled amount of unreactive chiral dopant. The elastomer films possess a 90° twist orientation even after the removal of the chiral dopant. The films exhibit an elongation and contraction in the direction at an angle of 45° relative to the mesogen orientations at the top and bottom surfaces in response to cooling and heating across the nematic-isotropic transition temperature, respectively.