Dual-Emissive Waterborne Polyurethanes Prepared from Naphthalimide Derivative
Tao Wang1, Xingyuan Zhang2, Yipeng Deng3
1CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China. wt0510@mail.ustc.edu.cn.
Polymers
|April 11, 2019
Summary
Researchers developed novel waterborne polyurethanes (WPUs) exhibiting both fluorescence and room-temperature phosphorescence (RTP). Introducing bromine atoms into dyes enhanced spin-orbit coupling, enabling dual emission and long RTP lifetimes.
Area of Science:
- Materials Science
- Polymer Chemistry
- Photophysics
Background:
- Fluorescent and room-temperature phosphorescent (RTP) materials are crucial for applications like bioimaging, sensing, optoelectronics, and encryption.
- Single-component dual-emissive materials offer advantages in simplifying system design and enhancing performance.
Purpose of the Study:
- To synthesize novel single-component dual-emissive waterborne polyurethanes (WPUs) capable of both fluorescence and RTP.
- To investigate the effect of halogenation and dye concentration on the luminescent properties of WPUs.
Main Methods:
- Synthesis of WPUs incorporating halogenated and non-halogenated dyes.
- Characterization of structural, thermal, and luminescent properties.
- Analysis of spin-orbit coupling and excimer formation effects.
Main Results:
- WPUs with non-halogenated dyes exhibited only fluorescence due to weak spin-orbit coupling.
- Introduction of bromine atoms into dyes in WPUs resulted in dual emission (fluorescence and RTP) with millisecond lifetimes.
- Increased dye concentration led to excimer formation, potentially enhancing singlet-triplet state communication.
Conclusions:
- Halogenation, specifically bromine incorporation, is an effective strategy to achieve RTP in WPUs.
- Dye concentration plays a significant role in modulating luminescent properties through aggregation and excimer formation.
- The developed dual-emissive WPUs show promise for advanced optical and sensing applications.
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