Synthesis and optical properties of new hyperbranched poly(p-phenylene ethynylene)s prepared via different A2 + B3 approaches

POLY 530

Michael Schroeter,, James D. Mendez,, and Christoph Weder, Department of Macromolecular Science and Engineering, Case Western Reserve University, 2100 Adelbert Road, 520 Kent Hale Smith Bldg, Cleveland, OH 44106-7202
Poly(p-phenylene ethynylene)s (PPEs) are an important class of conjugated polymers with interesting electronic and optical properties. Cross-linked PPE networks have recently been shown to display improved charge-transport characteristics when compared to their linear analogues, but they are also more difficult to process. Speculating that (hyper)branched PPEs might combine the electronic characteristics of network structures with the processability of linear macromolecules, we embarked on an investigation of such materials. A series of hyperbranched PPEs was synthesized by the palladium catalyzed cross-coupling polycondensation reaction of aromatic ethynylenes and halides. An A2 + B3 polymerization scheme was employed and 1,4-diethynyl-2,5-bis-(octyloxy)-benzene and 1,2,4-tribromobenzene were used as the A2 + B3 monomers, respectively. The emission and absorption spectra of the polymers display typical PPE behavior. A high degree of branching and end-capping of remaining halogen residues with phenylacetylene leads to materials with high fluorescence quantum yield.

Organic Thin Films for Photonic Applications
6:00 PM-8:00 PM, Tuesday, 12 September 2006 Moscone Center -- Hall D, Poster

8:00 PM-10:00 PM, Monday, 11 September 2006 Moscone Center -- Hall D, Sci-Mix

Division of Polymer Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006