Liquid crystal glycolipids - Carbohydrate Chemistry: Chemical and Biological Approaches - page 318

Fig. 7 The focal-conic texture of the smectic A* phase (x100).
Fig. 8 Effect of the number of hydroxyl groups on the smectic A to liquid and solid to
smectic A transition temperatures ( 1 C).
cyclic or acyclic structure of the sugar, the cycle size, the stereochemistry
at the carbohydrate chiral centres (anomeric or non anomeric) and the
hydrophobic chain length. Hereafter several of these variations are
discussed, including more recent studies which show how much crossed
effects of different structural parameters are important for giving a clear
view of the question.
The first family of alkyl-substituted polyols we describe, see Fig. 8, were
tested to evaluate the effect on clearing point (upper temperature of the
liquid crystal properties) of the thermotropic phases with respect to
increasing number of hydroxyl groups. 9 From the materials prepared, it
was found that the clearing point varied linearly with respect to the