Liquid crystalline side chain methacrylic azo containing polymers

Abstract

This paper describes the synthesis and characterisation of methacrylic liquid crystalline side chain polymer containing azo group, with (PM6OAn) and without (PM6An) hydroxyl group. The characterisation was done by using a polarised light microscope (PLM), differential thermal analysis (DTA), and X-ray diffractometry. All compounds developed bilayer smectic phase, with a certain degree of interdigitation between the layers. Poly[{3-hydroxy-4-[(E)-(4-octyloxyphenyl)diazenyl]phenoxy}hexyl]-2-methyl-prop-2-enoate (PM6OA8) exhibits a smectic A phase, whereas the other polymers show a SmC phase. Pyroelectric investigations show only an antiferroelectric behaviour for poly [{3-hydroxy-4-[(E)-(4-dodecyloxyphenyl)diazenyl]phenoxy}hexyl]-2-methylprop-2-enoate (PM6OA12) and a para-electric behaviour for PM6OA8, poly[{4-[(E)-(4-dodecyloxyphenyl)diazenyl]phenoxy}hexyl]-2-methylprop-2-enoate (PM6A12) and poly [{4-[(E)-(4-octyloxyphenyl) diazenyl] phenoxy} hexyl]-2-methylprop-2-enoate (PM6A8). Finall