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Published on: January 23, 2013
Structure-dependent photophysics studied in single molecules of polythiophene derivatives
Toshikazu Sugimoto1, Yohei Ebihara, Kenji Ogino
1Department of Organic and Polymeric Materials, Tokyo Institute of Technology, Ookayama 2-12-1-S8, Meguro-ku, Tokyo 152-8552, Japan.
Abstract:
We report on the photophysical characterization at the single-molecule level of a graft copolymer consisting of a polythiophene backbone and long polystyrene branches. The presence of the branches prevents the polymer chain from forming a collapsed conformational state. The photophysical properties of the resulting solution-like conformation are studied by measuring single-molecule photobleaching dynamics, emission polarization anisotropy and emission spectra. The results are compared with those obtained on the same polythiophene derivative without the branches. It is found that the presence of the branches is a decisive factor in determining the photophysical properties of the polymers on the single-molecule level.
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