Ellagic acid derivatives : a new mesogenic series exhibiting a thermotropic cubic mesophase
نویسندگان
چکیده
2014 Nine members of the tetra-n-alkanoyloxy ellagic acid series, ranging from the octanoyl to hexadecanoyl were synthesized and studied by calorimetry and optical microscopy. The octanoyloxy and nonanoyloxy derivatives are not mesogenic, while the other homologues exhibit a highly organized birefringent enantiotropic mesophase. Of these the five members with the longest side chains exhibit in addition a monotropic optically isotropic, and consequently, a cubic mesophase. From miscibility studies it appears that this cubic phase, which we name CD, is different from other cubic mesophases previously identified in non-chiral thermotropic mesogens. This monotropic CD mesophase can be maintained at room temperature in a metastable state for several weeks. J. Phys. France 50 (1989) 539-547 ler MARS 1989, Classification Physics Abstracts 61.30 v
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