TIT# Layer Morphology of a Poly(ester imide) LCP in Different Solid States
AUT# Stribeck, Norbert; Wutz, Christoph
SOU# Macromol. Chem. Phys. (2002), 203(2), 328-335
LOC# xv047
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ABS# A poly(ester imide) (PEI) in the smectic crystalline ($S_{E}$)
     state exhibits both a medium-angle X-ray scattering (MAXS)
     peak and discrete small-angle X-ray scattering (SAXS).
     Based on quantitative analysis of absolute scattering data
     the observed SAXS is attributed to the formation of a sandwich
     structure in which a central, well-ordered layer-shaped
     zone is enclosed in disordered buffer zones. Additionally
     the MAXS of material in the frozen liquid-crystalline $S_{A}$
     and $S_{B}$ states is analysed. The results show that
     the $S_{A}$ state is characterised by long ranging correlation
     in chain direction, whereas the lateral correlation range
     is short. Thus the smectic layer is considerably warped.
     The lateral range of order is wider in the $S_{B}$
     state and approaches infinity in the $S_{E}$
     state. This increase of lateral order and layer flatness
     goes along with considerable loss of longitudinal order.
     Nevertheless the range of longitudinal order remains high
     enough to assure correlation among the mesogens from the
     ordered zone with those from the disordered zones. Thus
     chain folding cannot be the primary reason for the formation
     of ordered and disordered zones. Results indicate that asymmetry,
     orientation and internal twist of mesogenic groups in a
     LC-main chain polymer are important parameters controlling
     structure formation of the smectic morphology.