Self-Reporting Fluorescent Step-Growth RAFT Polymers Based on Nitrile Imine-Mediated Tetrazole-ene Cycloaddition...

Area of Science:

• Polymer Chemistry
• Photochemistry
• Materials Science

Background:

• Step-growth polymerization kinetics are crucial for material properties.
• Real-time monitoring of polymerization can optimize synthesis and material design.
• Existing methods like NMR spectroscopy can be challenging in certain applications.

Purpose of the Study:

• To develop an inherently fluorescent self-reporting polymer system.
• To establish a fluorescence-based methodology for monitoring polymerization kinetics.
• To investigate the photoinduced nitrile imine-mediated tetrazole-ene cycloaddition (NITEC) process.

Main Methods:

• Utilizing a bismaleimide linker and a bifunctional α,ω-tetrazole-chain transfer agent (CTA).
• Employing α,ω-tetrazole-capped polystyrene as a photoreactive macromonomer.
• Monitoring polymer formation via UV irradiation and fluorescence emission.

Main Results:

• A fluorescent pyrazoline-containing polymer is produced upon UV irradiation.
• Fluorescence emission directly correlates with the number of ligation points in the polymer.
• Verified fluorescence-based quantification against NMR spectroscopy.

Conclusions:

• Developed an ideal self-reporting sensor system for step-growth polymers.
• Demonstrated the viability of fluorescence-based polymerization monitoring.
• Showcased a practical alternative to NMR spectroscopy in specific scenarios.