Self-assembling supramolecular systems of different symmetry formed by wedged macromolecular dendrons

Abstract

The main stages of the self assembling of supramolecular ensembles have been revealed by study ing different functional wedged macromolecules: polymethacrylates with tapered side chains based on gallic acid, their macromonomers, and salts of 2,3,4 and 3,4,5 tris(dodecyloxy)benzenesulphonic acid. The first stage is the formation of individual supramolecular aggregates (long cylinders or spherical micelles) due to the weak noncovalent interactions of mesogenic groups and the subsequent ordering in these aggregates, which is accompanied by a decrease in the free energy of the system. Supramolecular aggregates, in turn, form 2D or 3D lattices. The shape of supramolecular aggregates and its change with temperature are delicate func tions of the mesogen chemical structure; this circumstance makes it possible to rationally design complex self assembling systems with the ability to respond smartly to external stimuli. X ray diffraction analysis allows one to study the structure of supramolecular systems with different degrees of order, determine the type of mesophases formed by these systems, and reveal the phase behavior of the material. Particular attention has been paid to the method for reconstruction of electron density distribution from the relative reflection intensity. The application of a suite of experimental methods, including wide and small angle X ray diffrac tion, molecular modeling, differential scanning calorimetry, and polarization optical microscopy, allows one to establish the relationship between the shape of the structural unit (molecule or molecular aggregate), the nature of the interaction, and the phase behavior of the material.

Designing the topology of ion nano-channels in the mesophases of amphiphilic wedge-shaped molecules

“…Thus, it is typically supposed that a number wedge-shaped molecules ranging from 3 to 12 is contained in one slab forming a stable supramolecular column. [20][21][22][23][24] In our case, we observe a wide variation of the aggregation number as a function of water absorption, which shows the uniqueness of investigated molecular structure. This feature can make it possible to control the microstructure and the size of the nano-channels as a function of water swelling conditions.…”

The effect of the shape of the mesogenic group on the structure and phase behavior of 2,3,4-tris(dodecyloxy)benzenesulfonates with alkaline cations

“…Consequently, the most dramatic change is observed close to the column axis, where the low electron density of the ordered columnar mesophase switches to a high electron density in the disordered one. 35 Such a change manifests itself in different ratios of the reection intensities described above. The supramolecular cylinder can be regarded as a switchable ion channel, to be closed at higher temperatures and opened at lower ones.…”

“…3d symmetry formed by (C 6 F 13 -C 2 H 4 O-C 6 H 4 -CH 2 O) 3 -C 6 H 3 -CO-(OCH 2 CH 2 )4 -OH, i.e. gallic acid cores with long partially uorinated alkyl tails, is characterized by an expansion coefficient of b ¼ À7 Â 10 À4 K À1 [33][34][35]. Such thermal behaviour of a material…”

Helical Networks of π‐Conjugated Rods – A Robust Design Concept for Bicontinuous Cubic Liquid Crystalline Phases with Achiral Ia3¯d and Chiral I23 Lattice

“…[ 3 ] Bicontinuous cubic phases (Cub bi ) represent self‐assembled supramolecular networks of branched columns which occur in soft matter systems at the transition from lamellar to columnar self‐assembly. [ 4, 5 ] They are known for amphiphilic [ 6–8 ] and dendritic [ 9 ] molecules and for macromolecules [ 10 ] in the liquid crystalline (LC) phases of the bulk materials [ 11–21 ] and the corresponding lyotropic systems with appropriate solvents (in lyotropics abbreviated as Cub V phases). [ 7,22 ] They find applications for encapsulation of biological and bioactive molecules in drug delivery (cubosomes [ 23 ] ), gene transfection, and protein crystallization, [ 24 ] as templates for the preparation of inorganic porous materials, [ 25 ] as selective membranes, [ 26 ] photonic and optical bandgap materials, [ 27,28 ] and many other.…”