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Phase Behaviour of New Side-Chain Liquid Crystalline Polyoxetanes

✍ Scribed by Aránzazu Martínez-Gómez; Antonio Bello; Ernesto Pérez

Publisher
John Wiley and Sons
Year
2005
Tongue
English
Weight
602 KB
Volume
206
Category
Article
ISSN
1022-1352

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✦ Synopsis

Abstract

Summary: The synthesis and thermal behaviour of two new polyoxetanes with side chains having a dimer structure mesogen‐spacer‐mesogen and a long terminal alkyl group are reported. The two polymers differ in the chemical structure of the central spacer. The polyoxetanes have been obtained by cationic ring‐opening polymerisation of an appropriately substituted oxetane ring. Both polyoxetanes studied exhibit liquid crystalline properties showing a similar sequence of phases. DSC and synchrotron experiments indicate that a highly ordered phase with a probable orthorhombic packing is observed at low temperature. On heating, this phase melts into a mesophase with hexagonal order within the smectic layers, which, on further heating, is transformed into a disordered smectic mesophase.

Synchrotron X‐ray diffraction patterns of one of the poyoxetanes in a heating experiment.

magnified imageSynchrotron X‐ray diffraction patterns of one of the poyoxetanes in a heating experiment.

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