Self-organization of macromolecular materials by self-assembly

Abstract

Electrostatic self-assembly (ESA) methods have been used to synthesize thin and thick film organic/inorganic materials and devices. The ESA method involves the dip coating of charged substrates with alternating layers of anionic and cationic molecules, and the properties of the resulting multilayered structures depend on both the characteristics of the individual molecules and the spatial order of the layers. Since the process is performed at room temperature and pressure by dipping substrates into separate solutions containing the charged molecules, coatings may be formed on substrates of virtually any composition, shape and size. Materials that have been investigated for incorporation into such coatings include noble metal nanoclusters, metal oxide nanoclusters, polymers, cage-structured molecules such as fullerenes, proteins, and dipolar chromophore molecules. In this paper we investigate the self-organization that occurs in such materials at the molecular level, and show experimental examples of such self-organization made possible through atomic force microscopy, TEM and other visualization methods. In particular, we focus on the formation of ordered dipolar molecules that distribute electro-optic behavior, but discuss other ordered self- assembly observations.