Physicochemical characterization of octakis(alkyloxy)-substituted Zn(ii)-phthalocyanines non-covalently incorporated into an organogel and their remarkable morphological effect on the nanoscale-fibers

A series of octakis(alkyloxy)-substituted Zn(II)-phthalocyanines were efficiently incorporated into an organogel made of (1R,2R)-trans-1,2-bis(dodecanoylamino)cyclohexane by means of multiple cooperative non-covalent interactions, and SEM revealed the formation of unique brush-like nanostructures.

Two-Dimensional Aggregation of Organogelators Induced by Biaxial Hydrogen-Bonding Gives Supramolecular Nanosheets

Gelation of smectic liquid crystal phases with photosensitive gel forming agents.

This paper studies the potential of 3 newly synthesized low molecular weight gelling agents (2 of them with azo groups) with the semicarbazide group as a H-bonding motif to gel the smectic phase of a commercial chiral smectic C material. To detect gelation two methods were used: the stabilization of the director pattern, which measures the interaction of the physical gel network with the LC-director, and the suppression of the onset of electrohydrodynamic instabilities, which measures the increase of viscosity. Special emphasis was put on the influence of the photochemical - isomerization of the gelling agents on gelation.From the stabilization of the director pattern an elastic component c…

Two dimensional self-assembly of bis-acylureas having various functional end groups.

We present the synthesis and morphology study of thirteen bis-acylurea molecules with various functional end groups. The bis-acylureas have two acylurea groups, -NH-CO-NH-CO-, divided by a pentamethylene spacer, -(CH(2))(5)-, and two symmetric functional end groups, such as, aliphatic, benzyl, mono- and bi-thiophenyl, sulfur-containing, and propargyl (HC[triple bond]CCH(2)-) moieties. The bis-acylureas were synthesized by the coupling reactions of ureas with pimeloyl chloride or pimelic acid. Upon cooling from hot isotropic solutions, the bis-acylureas spontaneously form supermolecules. In the cases of aliphatic, benzyl, mono- and bi-thiophenyl functional groups, two dimensional supramolecu…

Photoresponsive anisotropic and isotropic gels of semicarbazide-azobenzene organogelators: the use of magnetic polymer colloids to detect gel-sol transformation.

Photoinduced gel-sol transformation of semicarbazide-azobenzene-based organogels containing entrapped organic solvents (isotropic gel) and liquid-crystalline material (anisotropic gel) has been studied. Thin films (4 µm) of gel materials were used to study the gel-sol transformation, as thicker films possess high absorbance due to the relatively high concentration of the gelator molecules. Photoinduced trans-cis isomerization of the azobenzene units causes destruction of the gel structure, and the consequent change in viscosity has been investigated employing magnetic polymer colloids. In the gel state the movement of the colloids is restricted due to their entrapment within the gel fibers …