| Abstract
| - Novel amphiphilic molecules, derivatives of gallic acid combining three hydrophilic 3,4-dihydroxypropyloxy(1-glyceryl) groups and one alkyl chain via central aromatic linking units (N-alkyl-3,4,5-tris(3,4-dihydroxypropyloxy)benzamides and n-alkyl 3,4,5-tris(3,4-dihydroxypropyloxy)benzoates) have beensynthesized. Their thermotropic and lyotropic phase behavior was investigated by hot stage polarized lightoptical microscopy, by differential scanning calorimetry, and in some cases by X-ray scattering. Lamellar(SA), type-1 bicontinuous cubic (CubV1), and type-1 hexagonal columnar (Colh1) mesophases have beenfound for the solvent-free compounds solely in dependence on the length of their alkyl chains. Hence, withthe exception of the micellar cubic phase (CubI1) all main mesophase types found in normal (type-1) lyotropicsystems have been successfully realized as their thermotropic analogues in the absence of any solvent.Additionally, binary systems of different amphiphiles have been investigated. In these systems phasesequences were obtained, which resemble those of lyotropic systems. The analysis of the induced phasesis proposed to be also a useful tool to assign the phase structure of thermotropic cubic mesophases. Onaddition of protic solvents Colh1 phases were introduced or stabilized, but no micellar cubic phases werefound.
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