Smectic LC-Elastomers with NO Shape Change at the Phase Transition

Liquid crystalline (LC) elastomers are well known for their reversible shape variation at the phase transition from the LC to the isotropic phase. We managed to prepare an oriented smectic monodomain of a crosslinked LC-polysiloxane which showed ‐ contrary to the expectations ‐ NO shape variation at all. This observation is in agreement with mechanical measurements on small LC-elastomer balloons made from the same materials. It is completely unknown why this type of “diluted” LC-polysiloxane (only about 25% of the repeating units are functionalized with mesogens) behaves like this.