|Title||Highly emissive conjugated polymer excimers.|
|Publication Type||Journal Article|
|Year of Publication||2005|
|Authors||Kim, Y, Bouffard, J, Kooi, SE, Swager, TM|
|Journal||Journal of the American Chemical Society|
|Keywords||pentiptycene quinone ring polyphenyleneethynylene excimer mediation emission tailoring, polyphenyleneethynylene prepn excimer mediation pendant ring structure|
Conjugated polymers often display a decrease of fluorescence efficiency upon aggregation due in large part to enhanced interpolymer interactions that produce weakly emissive species generally described as having excimer-like character. We have found that poly(phenylene ethynylene)s with fused pendant [2.2.2] ring structures having alkene bridges substituted with two ester groups function to give highly emissive, broad, and red-shifted emission spectra in the solid state. To best understand the origin of this new solid-state emissive species, we have performed photophysical studies of a series of different materials in solution, spin-coated thin films, solid solutions, and Langmuir films. We conclude that the new, red-shifted, emissive species originate from excimers produced by interchain interactions being mediated by the particular [2.2.2] ring system employed. The ability to design structures that can reliably produce highly emissive conjugated polymer excimers offers new opportunities in the emission tailoring of electroluminescence and sensory devices.