Origin of lyotropic liquid crystalline mesophase formation and liquid crystalline to mesostructured solid transformation in the metal nitrate salt-surfactant systems
Author
Albayrak, C.
Özkan, N.
Dag, Ö.
Date
2011Source Title
Langmuir
Print ISSN
0743-7463
Electronic ISSN
1520-5827
Publisher
American Chemical Society
Volume
27
Issue
3
Pages
870 - 873
Language
English
Type
ArticleItem Usage Stats
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Abstract
The zinc nitrate salt acts as a solvent in the ZnX-C12EO10 (ZnX is [Zn(H2O)6](NO3)2 and C12EO10 is C12H25-
(OCH2CH2)10OH) lyotropic liquid crystalline (LLC) mesophase with a drastic dropping on the melting point of
ZnX. The salt-surfactant LLC mesophase is stable down to -52 C and undergoes a phase change into a solid
mesostructured salt upon cooling below -52 C; no phase separation is observed down to -190 C. The ZnX-C12EO10
mesophase displays a usual phase behavior with an increasing concentration of the solvent (ZnX) in the media with
an order of bicontinuous cubic(V1)-2D hexagonal(H1) - a mixture of 2D hexagonal and micelle cubic(H1 þ I)-
micelle cubic(I)-micelle(L1) phases. The phase behaviors, specifically at low temperatures, and the first phase diagram
of the ZnX-C12EO10 system was investigated using polarized optical microscopy (POM), X-ray diffraction (XRD),
differential scanning calorimetry (DSC), Fourier transform infrared (FTIR), and Raman techniques and conductivity
measurements.