Abstract
We have made the twist nematic elastomer films where the local director continuously rotates by 90 degree between the top and bottom surfaces by the chiral imprinted method. The macroscopic shape of the elastomer ribbons with constant length and thickness depends on the width, temperature and the relation between the twist direction and long axis of the ribbons. In the cases where the director at the midplane is parallel to the long or short axis, the narrow ribbons form a helicoid with a finite Gaussian curvature whereas the wide ribbons prefer a spiral ribbon with almost no Gaussian curvature. In contrast, the ribbons whose midplane director is neither along the long nor short axis form a spiral ribbon independently of the width. In every case, the twist or helical pitch strongly depends on temperature. We analyze the observations on the basis of a theoretical model.
