Thermal deformation of imprinted twist nematic elastomers
نویسندگان
چکیده
A nematic elastomer film with a 90 o 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 o 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 o relative to the mesogen orientations at the top and bottom surfaces in response to cooling and heating across the nematic–isotropic transition temperature, respectively.
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