Direct Visualization of Individual Cylindrical and Spherical Supramolecular Dendrimers

Electron microscopy methods have been used to visualize individual spherical and cylindrical supramolecular dendrimers, providing definitive confirmation of the structures suggested by previous x-ray diffraction analysis that assumed a microsegregated model. These dendrimers are self-assembled, self-organized, and aligned spontaneously and simultaneously in hexagonal columnar or cubic thermotropic liquid-crystal phases with high uniformity. Homeotropic and planar ordering of the hexagonal columnar liquid crystal was precisely controlled by a variety of surfaces. The stiffness of these cylinders was evaluated by examining their planar texture and its defects.

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