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Updated: Aug 24, 2026

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Biaxial nematic phase in a thermotropic liquid-crystalline side-chain polymer
Kirsten Severing1, Kay Saalwächter
1Institut für Makromolekulare Chemie, Universität Freiburg, Stefan-Meier-Strasse 31, D-79104 Freiburg, Germany.
Abstract:
We report on variable-angle deuterium NMR measurements of nematic liquid-crystalline side-chain polymers, where we have found proof of the existence of a biaxial nematic phase in a system with a side-on attachment of the mesogenic group to the polymer backbone. This provides efficient coupling to the polymer backbone and thus stabilizes the as yet elusive biaxial phase. The experimental approach is validated on a uniaxial end-on nematic polymer, and the reliability of the results is investigated in detail using two-dimensional correlation spectra, providing information on director distribution effects.
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