Synthesis and properties of three novel series of monomers containing para-methoxyazobenzene as the mesogenic group

Three novel series of monomers, namely n-1-bromo-[4-(4-methoxyphenylazo)phe nyloxy]-alkanes (Bn, n = 3, 6, 10), n-[4-(4-methoxyphenylazo) phenyloxy]alk yloxy-4-methoxybenzene (Cn, n = 3, 6, 10) and n-[4-(4-methoxyphenylazo)phen yloxyl]alkyloxy-[4-methoxy-2,5-bis-(chloromethyl)] benzene (Dn, n = 3, 6, 1 0) were synthesized and characterized with FTIR, H-1 NMR, UV-visible and fl uorescence spectroscopy. Their thermal behaviour was studied by different s canning calorimetry and polarizing optical microscopy. The results show tha t B3, B6 and C6 exhibit monotropic nematic liquid crystalline behaviour.