DYE-CONTAINING S-C(ASTERISK) SIDE-ON END-ON COPOLYMERS

Mesomorphic copolysiloxanes, which combine 'normal' end-on linked chir al mesogenic units inducing S(C) phases and side-on fixed chromophore s were prepared. The interplay of the different orientational tendenci es of these moieties, which are perpendicular (end-on linked mesogenic groups) or parallel (side-on fixed chromophores) to the polymer chain , lead to a strong destabilization of the S(C) phase. However, copoly mers with up to about 10 mol% of chromophores still show a smectic C phase. FTIR measurements show that both moieties orient parallel to ea ch other and perpendicular to the polymer chains. These copolymers are interesting to consider as coloured guest-host S(C) materials for co loured displays or as pyre-electric detectors.