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Deformation experiments on chiral smectic C elastomers show a significant influence of the layer structure. In contrast to nematic systems a deformation of the smectic polydomain does not lead to a uniform director orientation. Obviously, the smectic layers lock in the polydomain structure in a transient network. Therefore, on experimental time scale, no equilibrium conditions can be achieved during the deformation process in the smectic state. Reducing the influence of the smectic layers by swelling the sample with toluene offers the possibility to prepare samples with uniform director orientation. In these samples the smectic layers are distributed on a cone around the director, preventing ferroelectric properties. Further deformation experiments on these aligned samples show a strong interaction of the layer orientation with the mechanical field in the smectic state. Layers which enclose large angles with the mechanical field realign to layer orientations with small angles to the deformation direction. This orientation behaviour leads to an anisotropic distribution of the layers on the cone causing a non-centrosymmetric phase structure. This anisotropic alignment can be locked in by chemical crosslinking, leading to a highly transparent non-centrosymmetric bulk material.

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It is well known that, with respect to the director, nematic elastomers can be macroscopically aligned by uniaxial mechanical fields. Extending this method to a chiral smectic C elastomer, depending on the experimental set-up either smectic layer orientation or director orientation parallel to the stress axis occurs. In order to align the director and the smectic layers a biaxial mechanical field (e.g. shear field) consistent with the phase symmetry has to be used to achieve a macroscopically uniform orientation of the untwisted smectic c* structure.

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