POS5-1316
Synthesis and Characterization of Open-Shell π-conjugated Near-Infrared Active Radical Polymers
When and Where
Nov 30, -0001
00:00 - 00:00
Presenter(s)
Meenakshi . (Pusan National University)
Co-Author(s)
Abstract
Neutral organic radicals represent a highly promising class of materials for next-generation optoelectronic devices due to their unique open-shell electronic structures characterized by unpaired electrons. When incorporated into the backbone of conjugated polymers, these organic radicals can yield highly emissive materials suitable for organic light-emitting applications. To achieve practical utility, these polymers must carefully balance electronic delocalization with necessary steric shielding to protect the reactive radical centers. While such structural designs afford stability, realizing efficient radical-based emission in the near-infrared (NIR) spectrum—particularly at wavelengths exceeding 750 nm—remains a formidable scientific challenge. Herein, we report the synthesis and characterization of a novel series of donor-acceptor (D-A) type open-shell π-conjugated polymer radicals developed for effective NIR emission. The conjugated polymer backbones are structurally supported by robust mesitylated tris(2,4,6-trichlorophenyl)methyl (TTM) radical acceptors covalently linked with varying electron-rich donors: fluorene (FL), diphenylamine (DPA), and phenothiazine (PTZ). This strategic design resulted in the highly emissive NIR-active polymers PTTMFL, PTTMDPA, and PTTMPTZ, respectively. By systematically varying the donor units, subsequent photoluminescence data demonstrated that the optical bandgaps and emission profiles of the polymers can be effectively fine-tuned. Furthermore, electron paramagnetic resonance (EPR) spectroscopy confirmed the successful generation of radical sites post-polymerization. Complementary UV-Vis spectroscopy and cyclic voltammetry analyses confirmed the excellent solution-phase and electrochemical stability of these polymers under ambient conditions. Ultimately, these findings position mesitylated TTM-based polymer radicals as highly promising candidates for the development of next-generation organic luminescent materials.
