Electroactive hybrid copolymers

Miller and co-workers have recently prepared nanometer-scaled molecular dumbbells based on poly(benzyl ether) dendrons (G1-G4) and oligoimide spacers [64], Their synthetic approach involved the coupling of amine-terminated oligoimides to dendrons with a carboxylic acid focal point. The resulting hybrid materials were found to be quite soluble thus allowing their analysis by cyclic voltammetry in DMF. Consistent with Roncali s observation, the kinetics of reduction of the oligoimide core was not found to be limited by the presence of the dendritic wedges. 

Stoddart and co-workers have made use of Frechet-type dendrons as dendritic stoppers for self-assembled [n]rotaxanes [65]. The solubility enhancement that results from incorporating dendritic wedges at the termini facilitated the purification of these materials by column chromatography despite the polycationic nature of their bipyridinium backbone. Again, the dendritic wedges did not alter the electrochemical characteristics of the viologen subunits. Flowever, the enhanced solubility resulting from the presence of the dendritic components en- 

Ultimately, the encapsulated chromophore must be interfaced with hole- and electron-transporting elements to afford an actual OLED device. In this context, a dendrimer is ideally suited since it not only provides steric protection (site 

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Scheme 3 Synthesis of Au-hybrid nanoparticles with electroactive copolymer shell structure...

Several approaches used to prepare hybrid polymers in which polyacetylene is an electroactive component are presented. Specifically, these involve the preparation of (1) composites by in-situ polymerization, (2) graft copolymers utilizing carbanions in n-type (CH)X as polymerization initiators, and (3) A-B diblock copolymers exploiting anionic-to-Ziegler-Natta transformation reactions. 

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