Modern Polymer Spect..

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Figure 2-42. FTIR polarization spectra of the copolymers with chromophore I (a) and I1 (b) after
shearing (IR-radiation polarized parallel (- - -) and perpendicular (-) to the shearing direction) (the
arrow indicates the \),(NO?) absorption of the chromophore).
ment of an external stabilizing (mechanical) field. A characteristic feature of this
state of order is the optical transparency of the material. The optical behavior of
such elastomers is comparable with organic or inorganic single crystals. Kiipfer and
Finkelinam [ 1 1 11 have described the synthetic route for LSCEs with a permanent
mesogen orientation.
2.7.2.1 Materials
The LSCE system investigated in the present work is based 017 a methylsiloxane
elastomer which has been crosslinked in a two-step procedure (Figure 2-43 j. The
mesogenic side groups have been attached via a vinyl end-group (compound 2) and
the crosslinking agents are a hydrochinonedialkylether with vinyl end-groups