PIEZOELECTRICITY OF MECHANICALLY ORIENTED S-ASTERISK(C)-ELASTOMERS

Ferroelectricity and thus piezoelectricity are well known features of low molar mass chiral smectic C (S-c) liquid crystals. We present a n ew technique to orientate macroscopically the director as well as the smectic layers of a S-c-polymer network by applying a suitable mechan ical field. The uniform orientation of the network film is checked by X-ray diffraction. According to the phase symmetry electromechanical m easurements indicate the existence of a polar axis of the network and the direct as well as the inverse piezoelectric effect is demonstrated .