| Abstract
| - New 2,4-diamino-6-phenyl-1,3,5-triazines carrying one or two semiperfluorinated chains at the phenylsubstituent have been synthesized. The thermotropic liquid crystalline properties of the compounds wereinvestigated by polarizing microscopy, differential scanning calorimetry, and X-ray diffraction. The single-chain compounds exhibit a lamellar (SmA) mesophase with intercalation of the polar rodlike aromaticsubunits. The two-chain partially fluorinated triazine forms a reverse discontinuous (micellar) cubic phase(CubI2). Additionally, binary mixtures of a single-chain triazine with the two-chain semiperfluorinatedtriazine were investigated. Inverted bicontinuous cubic (CubV2) and hexagonal columnar (Colh2) phasesare induced as intermediate between the lamellar and the micellar cubic mesophases of the pure compounds.On addition of protic solvents such as formamide, the CubI2 phase of the two-chain triazine is replacedby a lyotropic columnar mesophase.
- New thermotropic 2,4-diamino-6-phenyl-1,3,5-triazines bearing semiperfluorinated alkyl chains are presented. Depending on the number of the partially fluorinated terminal chains the compounds exhibit lamellar or micellar cubic mesophases. The phase sequence SmA−bicontinuous cubic−hexagonal columnar−micellar cubic was realized in a binary system of a one-chain triazine with a two-chain fluorinated triazine without any solvent.
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