Liquid crystal polymers

Abstract

Compounds of formula ##STR1## are provided which may be used in a variety of devices including liquid crystal devices, piezoelectric devices, pyroelectric devices and in optical recording media, wherein X.sub.1 and X.sub.2 are independently selected from H, CN, COCH.sub.3, CO.sub.2 CH.sub.3, m=at least 5; X.sub.3 and X.sub.4 are independently selected from formula (IA), ##STR2## wherein Y is selected from COO, OCO, O, S, CHOH, CHF, CH.sub.2 ; Q=(CH.sub.2).sub.n wherein one or more non-adjacent methylenes may be replaced by O and n=1-20; Z is selected from O, S, single covalent bond, COO, OCO; when Y is CH2 then n may also be O; formula (A) ##STR3## represents any mesogenic group; X3 and X.sub.4 are also independently selected from H, OH, OCOR.sup.1, COOH, CO.sub.2 R.sup.1 (CH.sub.2).sub.p OH, (CH.sub.2).sub.p CO.sub.2 H, --(CH.sub.2).sub.p OR.sup.1 or --(CH.sub.2).sub.p CO.sub.2 R.sup.1 and p=1-20, R.sup.1 =H or C.sub.1=16 alkyl, when R.sup.1 =C.sub.2-16 alkyl the terminal Ch.sub.3 group may be replaced by Br or Cl; provided that at least one of X3 and X4 is selected from formula (IA).

Dependencies are inferred from the claim text.