Columnar liquid crystals in oligosaccharide derivatives. II. Two types of discotic columnar liquid-crystalline phase of cellobiose alkanoates
1992; Taylor & Francis; Volume: 12; Issue: 2 Linguagem: Inglês
10.1080/02678299208030401
ISSN1366-5855
AutoresAkihiko Takada, Takeshi Fukuda, Taito Miyamoto, Y. Yakoh, Junji Watanabe,
Tópico(s)Plant Reproductive Biology
ResumoAbstract A series of cellobiose octaalkanoates, Cel-II-n (n is the carbon number of the alkyl chain), with n = 7–14 were prepared and their mesogenic properties examined by differential scanning calorimetry, optical polarizing microscopy and X-ray diffraction. All of these compounds form enantiotropic discotic columnar phases, in which the columns are built up by a regular stacking of the cellobiose moieties and are packed in a two dimensional lattice. Homologues with n = 9–14 form the Dho phase only whilst the compound with n = 7 forms the Dro phase. The n = 8 compound forms the Dho phase at higher temperatures and the Dro phase at lower temperatures. Structural parameters obtained from X-ray diffraction studies are presented for both phases.
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