A new homologous series of thermally stable thermotropic liquid crystalline poly(arylidene-ether)s
based on 4-tertiary-butyl-cyclohexanone moiety was synthesised by solution polycondensation of
4,4
-diformyl-
α
,
ω
-diphenoxyalkanes,
I
a–f
,or4,4
-diformyl-2,2
-dimethoxy-
α
,
ω
-diphenoxyalkanes,
II
a–f
, with
the 4-tertiary-butyl-cyclohexanone monomer. A model compound
III
was synthesised from the monomer with
benzaldehyde and characterised by elemental and spectral analyses. The inherent viscosities of the resulting
polymers were in the range of 0.18–0.92 dL/g. The mesomorphic properties of these polymers were studied as a
function of the diphenoxyalkane space length. Their thermotropic liquid crystalline properties were examined by
differential scanning calorimetry (DSC) and optical polarising microscopy and demonstrated that the resulting
polymers form nematic mesophases over wide temperature ranges. The thermal properties of those polymers were
evaluated by thermogravimetric analysis and DSC measurements and correlated to their structural units. X-ray
analysis showed that polymers having some degree of crystallinity in the region 2
θ
=
5–60
◦
. In addition, the
morphological properties of selected examples were tested by scanning electron microscopy.