Mesomorphic properties of a new homologous series of ortho hydroxyl-functionalized Schiff bases

Abstract

Nine members of a homologous series of the Schiff bases
[4(4'-n-alkoxy -2- hydroxybenzylidene ) amino biphenyl ] have been prepared and
their mesomorphic properties and phase transitions were determined for all
compounds by polarizing hot stage microscopy and differential calorimatry for some
of them . The properties of this series are compared with those the analogous Schiff
bases , the [4(4'-n-alkoxy -2- hydroxybenzylidene ) amino biphenyl ] .The effect of
the hydroxyl group in ortho position on the type of liquid crystal phases in this series
and thermal stability has been assessed