1228276-91-2Relevant articles and documents
Homeotropically aligned self-organizing dendronized polymer
Barkley, Deborah A.,Koga, Tadanori,Rudick, Jonathan G.
, p. 2849 - 2854 (2015)
Self-organizing dendronized polymers embody the bottom-up paradigm for the self-assembly of nanostructured materials. The presence of a dendritic side chain on each repeat unit of the linear polymer backbone gives dendronized polymer chains a nanometer-sized diameter, and this dimension can be tailored though the generation number of the dendrons, the peripheral groups on the dendrons, or the branching number of the repeating unit in the dendrons. Self-assembling dendrons with semifluorinated peripheral groups and polymers dendronized via supramolecular interactions with these dendrons have been reported to homeotropically align on glass surfaces. However, most derivatives of these semifluorinated dendrons.
Self-assembly of imidazolium-based rodlike ionic liquid crystals: transition from lamellar to micellar organization
Cheng, Xiaohong,Bai, Xueqing,Jing, Shan,Ebert, Helgard,Prehm, Marko,Tschierske, Carsten
supporting information; experimental part, p. 4588 - 4601 (2010/08/19)
By using aryl-amination chemistry, a series of rodlike 1-phenyl1H- imidazole-based liquid crystals (LCs) and related imidazolium-based ionic liquid crystals (ILCs) has been prepared. The number and length of the C-terminal chains (at the noncharged end of the rodlike core) and the length of the N-terminal chain (on the imidazolium unit in the ILCs) were modified and the influence of these structural parameters on the mode of self-assembly in LC phases was investigated by polarizing microscopy, differential scanning calorimetry, and X-ray diffraction. For the single-chain imidazole derivatives nematic phases (N) and bilayer SmA2 phases were found, but upon increasing the number of alkyl chains the LC phases were lost. For the related imidazolium salts LC phases were preserved upon increasing the number and length of the C-terminal chains and in this series it leads to the phase sequence SmA-columnar (Col)-micellar cubic (Cuby1/Pm3n). Elongation of the N-terminal chain gives the reversed sequence. Short Nterminal chains prefer an end-to-end packing of the mesogens in which these chains are separated from the C-terminal chains. Elongation of the N-terminal chain leads to a mixing of N- and C-terminal chains, which is accompanied by complete intercalation of the aromatic cores. In the smectic phases this gives rise to a transition from bilayer (SmA2) to monolayer smectic (SmA) phases. For the columnar and cubic phases the segregated end-to-end packing leads to core-shell aggregates. In this case, elongation of the N-terminal chains distorts core-shell formation and removes Cub1 and Col phases in favor of single-layer SmA phases. Hence, by tailoring the length of the N-terminal chain, a crossover from taper-shaped to polycatenar LC tectons was achieved, which provides a powerful tool for control of self-assembly in ILCs.
