Shape dependence in the formation of condensed phases exhibited by disubstituted sucrose esters.
We report on the self-organizing properties of sucrose esters that are di-(1',6', 1',6, and 6,6')-substituted with aliphatic chains of identical or different chain lengths and levels of saturation. For the materials possessing two saturated aliphatic chains, the compounds exhibited thermotropic lamellar smectic A phases. A remarkable new phase transition was observed for the di-octadecanoyl homologue in which one smectic A phase transformed into another with a continuous change in layer spacing, but with a discontinuous change in the correlation length. The incorporation of long cis-unsaturated chains led to increased cross-sectional areas of the chains relative to the sucrose head groups and, hence, columnar phases were observed.
Molinier
Valérie
V
Laboratoire de Chimie Organique, UMR 5181 CNRS; Université Lyon 1, France.
Kouwer
Paul J J
PJ
Fitremann
Juliette
J
Bouchu
Alain
A
Mackenzie
Grahame
G
Queneau
Yves
Y
Goodby
John W
JW
D002152:Calorimetry, Differential Scanning; D004952:Esters / Q000737:chemistry*; D006017:Glycolipids / Q000737:chemistry*; D007536:Isomerism; D008051:Lipid Bilayers / Q000737:chemistry*; D008859:Microscopy, Polarization; D044367:Phase Transition; D013228:Stearates / Q000737:chemistry*; D013395:Sucrose / Q000737:chemistry*; D013696:Temperature; D014961:X-Ray Diffraction
D004952:Esters; D006017:Glycolipids; D008051:Lipid Bilayers; D013228:Stearates; D013395:Sucrose