Characterization of Dendrimer-Based Nanocomposites by Saxs and Sans

Abstract

Dendritic polymers have been used as soluble templates/unimolecular reactors from which nano-clusters of inorganic compounds were synthesized. These organic/inorganic, dendrimerbased hybrid species or “nanocomposites” display unusual properties, i.e., their solubility is deterrnined by the properties of the dendrimer molecules. Since it has been established that there is no covalent bond between the dendrimer host and the inorganic guest, these observations suggest that the guests are physically and spatially restricted by the dendrimer shell. However, this structure has not been verified. In this investigation a preliminary understanding of the physical structure of these dendrimer-based nanocomposites was sought. A model system of PAMAM dendrimer-copper sulfide nanocomposites was studied in various stages of its formation using a combination of small angle X-ray and neutron scattering experiments. The results suggest that little perturbation of the dendritic species occurs on complexation, but indicate that a secondary supermolecular aggregation phenomena occurs within nanocomposite solutions.