Functional dendritic macromolecules: Preparation and optical properties

Repetitive coupling reactions of branched azobenzene derivatives resulted in dendritic macromolecules, or "wedges" and "dendrimers". These molecules were designed to incorporate aliphatic and polar units in order to prepare Langmuir-Blodgett (LB) films. Atomic force microscopy (AFM), absorption spectroscopy, and second harmonic generation (SHG) measurements revealed structural properties of the LB films in terms of size, aggregation, and orientation, AFM measurements revealed that growth of the branches increased as a function of the generation. In absorption spectroscopy and SHG measurements, results showed that wedges had an unsymmetric orientation in the LB films, while dendrimers had a symmetrically functionalized structure.