Optical and electroluminescent properties of conjugated polyrotaxanes

Abstract

Conjugated polyrotaxanes are conjugated polymeric semiconductors engineered at a supramolecular level by threading the conjugated moiety into molecular macrocycles, such as cyclodextrins (CD). CD-threaded rotaxanes thus provide a class of model compounds with reduced interchain interactions which enable us to explore the influence of such interactions on the fundamental photophysics of conjugated semiconductors. CD rotaxination also endows these materials with additional sites for functionalization, thus resulting in extremely versatile structures. Our current understanding of the photophysics of these materials is reviewed, both in solid/liquid solutions and in neat films, as a function of the relevant parameters, such as the threading ratio and the concentration, and with the help of rotaxanes incorporating a variety of different backbones. Conjugated polyrotaxanes obtained via threading of conjugated polymers into cyclodextrin (CD) rings are prototypical examples of semiconductors that are engineered at a supramolecular level. Cyclodextrins act primarily as molecular spacers, and prevent close intermolecular interaction, thus affording substantial control on important aspects of conjugated polymers photophysics. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.