| Abstract
| - T-shaped polyphilic triblock molecules, consisting of a rodlike p-terphenyl unit, a hydrophilicand flexible laterally attached oligo(oxyethylene) chain terminated by an 1-acylamino-1-deoxy-d-sorbitolunit, and two end-attached lipophilic alkyl chains, have been synthesized by palladium-catalyzed cross-coupling reactions as the key steps. The thermotropic liquid crystalline behavior of these compounds wasinvestigated by polarized light microscopy, differential scanning calorimetry (DSC), and X-ray scattering.We investigated the mode of self-organization as a function of the length and position of the lateral polarchain and the length of the terminal alkyl chains. Depending on the size of the polar and lipophilic segments,a series of unusual liquid crystalline phases was detected. In three of these phases, the space is dividedinto three distinct periodic subspaces. In addition to a hexagonal channeled layer phase (ChLhex) consistingof layers that are penetrated by polar columns, there are also two honeycomb-like network structures formedby square (Colsqu/p4mm) or pentagonal cylinders (Colsqu/p4gm). The cylinder walls consist of the terphenylunits fused by columns of alkyl chains, and the interior contains the polar side chains. In addition, a hexagonalcolumnar phase was observed in which the polar columns are organized in a continuum of terphenyls andalkyl chains with an organization of the terphenyl cores tangentially around the columns with the long axisperpendicular to the columns. For one compound, a reversal of birefringence was observed, which isexplained by a reorientation of the terphenyl cores. The addition of protic solvents induces lamellar phases.
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