Abstract
The thermotropic phase behavior of phthalocyanines (Pc's) with eight oligo(ethylene oxide) alkoxy side chains has been investigated. An increase in the number of ethylene oxide units results in a decrease in the solid-to-mesophase and isotropization temperatures. The investigated compounds display a discotic hexagonally ordered (D-ho) mesophase. The solubilization of LiI/I-2 into the polar side chains of the Pc's has been studied both in solution and in spin-coated films, and the effect on the aggregate formation is discussed. At higher temperatures, the Pc - LiI/I-2 complex is not stable and small crystallites are formed. The dark direct current conductivity of these films is reported as a function of LiI/I-2 concentration in the polar side groups of the Pc's. The observed decrease in conductivity with increasing salt concentration is related to the morphology of the material. Copyright (C) 2003 Society of Porphyrins & Phthalocyanines.