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Monitoring the Effects of Illumination on the Structure of Conjugated Polymer Gels Using Neutron Scattering
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Electrical Conductivities of Narrow-Bandgap Polymers with Two Types of π-Conjugated Post-Crosslinking
Hao-Xuan Guo1, Hiroshi Takahara1, Yusuke Imai1
1Department of Chemistry and Materials Engineering, Kansai University, Suita 564-8680, Osaka, Japan.
Polymers
|June 24, 2022
Summary
Researchers developed simple methods for creating narrow-bandgap polymers. Post-crosslinking these conducting polymers significantly enhanced their electrical conductivity for electronic applications.
Area of Science:
- Materials Science
- Polymer Chemistry
- Organic Electronics
Background:
- Bandgap energy is crucial for electrical conductivity in electronic devices.
- Developing narrow-bandgap conducting polymers is challenging due to complex preparation methods.
Purpose of the Study:
- To synthesize water-soluble, narrow-bandgap polymers with reactive groups.
- To investigate the effect of post-crosslinking on polymer properties and conductivity.
Main Methods:
- Addition-condensation reaction of pyrrole, benzaldehyde-2-sulfonic acid sodium salt, and aldehyde-containing reactive groups.
- Post-crosslinking via reactions of aldehyde with p-phenylenediamine and pyridine with 1,2-dibromoethylene.
- Characterization using 1H-NMR, TG/DTA, and UV-Vis-NIR spectroscopy.
Main Results:
- Synthesized narrow-bandgap polymers with bandgaps < 0.5 eV.
- Post-crosslinking improved electron-conducting routes and prevented resolubility.
- Electrical conductivity increased by two orders of magnitude after crosslinking.
Conclusions:
- The developed method offers a simpler route to narrow-bandgap conducting polymers.
- Post-crosslinking is an effective strategy to enhance the electrical properties of these polymers.
- The resulting materials show promise for electronic device applications.
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