Hexagonal tubular phases

Fig. 51 Schematic structures of the hexagonal tubular nematic and rectangular tubular nematic phases. The mesogenic groups are roughly parallel to the columns but their positions are disordered. Thus the columns effectively act as the directors of the nematic phase...

Microporous silicas with pore size of 12.2 A were prepared by either S XT or S " pathways at room temperature using dodecyidimethylbenzylammonium chloride (DDBAC) surfactant. The pore size of the synthesized materials could be tuned from microporous to mesoporous range by the crystalline temperature or using mixed surfactants of DDBAC and cetyl-pyridinium chloride. The pore structure can transfer from disordered tubular array to ordered hexagonal phase by the increase of the molar ratio of CPCl to DDBAC. 

Interestingly, this elaborated sector approach to tubular materials can be executed using perhaps the simplest possible starting materials as molecular sectors. Variations within this basic framework alter the lipid molecular shape, which allows lipid assemblies to access a wide range of structural morphologies, ranging from micellar and hexagonal phases to the lamellar structure found in biomembranes. ... 

Kwon YK, Chvalun S, Schneider A-1, Blackwell J, Percec V, Heck JA (1994) Supramolecular tubular structures of a polymethacrylate with tapered side groups in aligned hexagonal phases. Macromolecules 27(21) 6129-6132. doi 10.1021/ma00099a029... 

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