Metallosupramolecular conjugated polymers

POLY 7

Christoph Weder, christoph.weder@case.edu, Department of Macromolecular Science and Engineering, Case Western Reserve University, 2100 Adelbert Road, 416 Kent Hale Smith Bldg, Cleveland, OH 44106-7202
The use of metal-ligand binding as the driving force for the self-assembly polymerizations of a ditopic macromolecule offers a facile route to the preparation of linear metallo-supramolecular conjugated polymers as well as to cross-linked metallo-supramolecular conjugated polymer networks. We summarize our activities in this field and report on the polymerization of different conjugated macromonomers that were derived by end-capping low-molecular weight poly(p-2,5-dialkoxy phenylene ethynylene)s cores with 2,6-bis(1'-methyl-benzimidazolyl)pyridine (Mebip) ligands. The supramolecular polymerization of these macromonomers with equimolar amounts of Zn2+ or Fe2+ resulted in polymers, which exhibit appreciable mechanical strength, but due to their dynamic, reversible nature offer the ease of processing of low-molecular weight compounds. We also report on the investigation of organometallic networks, which are formed through ligand-exchange reactions between ligand sites comprised in the organic semiconductor and metallic cross-links. The available data indicate that cross-linking can have significant benefits for intermolecular charge transfer, if the polymers are carefully designed.