Cationic Polyelectrolytes, Stable in 10 M KOH_aq at 100 °C

Area of Science:

• Polymer Chemistry
• Materials Science
• Electrochemistry

Background:

• Cationic polyelectrolytes are crucial for various electrochemical applications.
• Developing materials with high alkaline stability remains a significant challenge.
• Poly(arylene-imidazoliums) offer a promising structural motif for robust polymers.

Purpose of the Study:

• To synthesize and characterize novel poly(arylene-imidazoliums).
• To investigate the exceptional alkaline stability of these polymers.
• To explore their potential for creating ionically conductive films.

Main Methods:

• Microwave-assisted polycondensation of dialdehyde with bisbenzil.
• Quantitative functionalization via alkylation.
• Stability testing in concentrated alkaline solutions (10 M KOH at 100 °C).
• Characterization using model compounds, X-ray diffraction, and density functional theory.

Main Results:

• Successfully synthesized sterically protected poly(arylene-imidazoliums).
• Achieved remarkable alkaline stability with a half-life exceeding 5000 hours in 10 M KOH at 100 °C.
• Rationalized stability through structural analysis and computational modeling.
• Demonstrated the formation of tough, pliable, transparent, and ionically conductive films.

Conclusions:

• Poly(arylene-imidazoliums) exhibit unprecedented stability in harsh alkaline conditions.
• The C2-steric protection is key to their enhanced durability.
• These polyelectrolytes are suitable for applications requiring robust ionic conductivity in alkaline media.