Functionalized Imidazolium Ether-Free Polymer Backbones with Ion Transport Channels and Catalytic Activity

Area of Science:

• Polymer Chemistry
• Materials Science
• Catalysis

Background:

• Development of ether-free polymer backbones is crucial for advanced materials.
• Imidazolium groups are key for functionalizing polymers for specific applications.
• Anion exchange membranes (AEMs) require polymers with excellent ion transport properties and stability.

Purpose of the Study:

• To synthesize novel ether-free polymers with imidazolium groups for AEMs.
• To investigate the properties of these polymers for electrochemical applications.
• To explore the potential of these polymers as precursors for organometallic catalysts.

Main Methods:

• Polycondensation in a superacid medium using p-terphenyl and 4-(1H-imidazol-1-yl)benzaldehyde.
• Nucleophilic substitution for introducing cationic sites.
• Characterization using NMR, FTIR, AFM, HR-TEM, SAXS, SEM, and XPS.
• Evaluation of water uptake, ion exchange capacity, ion conductivity, morphology, thermal, and mechanical stability.

Main Results:

• Successful synthesis of ether-free polymers with imidazolium groups.
• Membranes exhibited distinct hydrophilic/hydrophobic microphase separation, forming ion transport channels.
• High hydroxide conductivities of 61.33 and 80.33 mS/cm at 80 °C were achieved for 1AIM and 1ABPTA polymers, respectively.
• Polymers demonstrated thermal stability up to 240 °C.
• Organometallic polymers were synthesized and showed catalytic activity in Suzuki-Miyaura coupling (70% and 60% conversion in the first two cycles).

Conclusions:

• The synthesized ether-free polymers are promising candidates for anion exchange membrane applications due to their ion transport capabilities and stability.
• The imidazolium groups facilitate the creation of functional organometallic catalysts.
• These versatile polymers hold potential for both energy storage/conversion and catalytic applications.