Relation Between the Crystalline Structure and the S _E - Phase of VINYL-P-(P’-N- HEXYLOXYPHENYL)BENZOATE

Abstract

Liquid crystalline polymers can be divided in two groups; either the mesophase inducing group is part of the main chain or the liquid crystalline behaviour is induced by mesogenic side-chains. As part of a more elaborate work in the latter area the following compound was obtained by synthesis: vinyl-p-(p’-n-hexyloxyphenyl)benzoate. Liquid crystalline transformations for this compound were detected by DSC and optical microscopy. An arced focal-conic form texture was observed at T=61.91°C and another transformation occurred at T=100.03°C. The latter structure was identified to be a smectic A-phase and the former was assigned a smectic E-phase on the basis of X-ray observations. This low molecular weight compound was selected for studies of polymerisation in organized phases. There seems to be little literature information on the relation between crystal structure and the structure on the highly organized S _E -phases. Hence the present work was undertaken to explore these structure features as well as to broaden knowledge in the field.