Moderated ionic bonding for water-free recyclable polyelectrolyte complex materials

Area of Science:

• Polymer Science
• Materials Science
• Electrochemistry

Background:

• Nature utilizes electrostatic bonding for material assembly, but synthetic ionic polymers often require water to prevent brittleness and processing difficulties.
• High-density ionic cross-linking in synthetic polyelectrolyte complexes leads to strong Coulombic forces upon dehydration, rendering them brittle and non-thermoplastic.
• Existing synthetic ionic materials face challenges in processability and stability outside aqueous environments.

Purpose of the Study:

• To develop a novel class of synthetic polymer materials with tunable electrostatic interactions.
• To overcome the limitations of traditional polyelectrolyte complexes, particularly their water dependency and processing challenges.
• To create processable, durable, and recyclable materials based solely on ionic bonding.

Main Methods:

• Covalently grafting attenuator spacers to charge-carrying moieties within apolar polymeric solids.
• Synthesizing and characterizing these modified polymers, termed "compleximers."
• Evaluating the processability, solvent resistance, and recyclability of the new materials.

Main Results:

• Introduced "compleximers," a new class of polyelectrolyte materials with intrinsically moderated electrostatic bond strengths.
• Achieved 100% charge density in materials that are processable and malleable without water.
• Demonstrated high solvent and water resistance, alongside full recyclability.
• Successfully combined thermoplastic and thermoset properties using tailored ionic bonding.

Conclusions:

• The covalent grafting strategy effectively moderates ionic bond strengths in polymeric solids.
• Compleximers offer a versatile platform for creating advanced materials with tunable properties.
• This approach enables the development of water-free, processable, and recyclable ionic polymer materials.