A COLORED FERROELECTRIC SIDE-CHAIN POLYMER

Coloured ferroelectric liquid-crystalline side chain copolymers containing 5 per cent and 15 per cent of an azo dye were synthesized and characterized by DSC, GPC and optical microscopy. Order parameters, S, of the azo compound exceeding 0.8 were measured in the frozen smectic phase for the 5 per cent copolymer. The copolymers exhibit fast electrooptic switching in the range of a few hundred microseconds to milliseconds in the S(C)* phase. Both linear (i.e. electroclinic-like) and ferroelectric switching have been observed. Tilt angles of approximately 19 and spontaneous polarization of approximately 300 nC cm-2 have been recorded in the S(C)* phase.