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Published on: December 21, 2017
Relating conformation and photophysics in single MEH-PPV chains
1Department of Organic and Polymeric Materials, Tokyo Institute of Technology, Ookayama 2-12-1, Meguro-ku, Tokyo, Japan.
The Journal of Physical Chemistry. B
|September 17, 2008
Summary
We studied conjugated polymer conformations using advanced microscopy and simulations. Chain structure directly impacts photophysical properties, revealing how microscopic changes alter polymer behavior.
Area of Science:
- Polymer Science
- Photophysics
- Microscopy
Background:
- Conjugated polymers like MEH-PPV are crucial for organic electronics.
- Understanding their conformational dynamics is key to optimizing optoelectronic properties.
- Existing methods struggle to link microscopic structure to macroscopic photophysics.
Purpose of the Study:
- To determine the conformation of individual isolated chains of MEH-PPV.
- To correlate these conformations with the polymer's photophysical properties.
- To provide direct evidence for the structure-property relationship in conjugated polymers.
Main Methods:
- Utilized a novel fluorescence polarization microscope for high-resolution imaging.
- Employed molecular dynamics calculations to model polymer behavior.
- Measured fluorescence intermittency on individual polymer chains.
Main Results:
- Identified distinct conformations: defect cylinders in poor solvents and defect coils in good solvents.
- Established a direct link between specific chain conformations and observed photophysical properties.
- Demonstrated that subtle changes in polymer structure significantly alter photophysics.
Conclusions:
- Chain conformation is a primary determinant of MEH-PPV photophysics.
- Microscopic structural variations have a qualitative impact on photophysical behavior.
- This work provides a foundation for designing polymers with tailored optoelectronic functions.
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