Revisiting Acetoacetyl Chemistry to Build Malleable Cross-Linked Polymer Networks via Transamidation

Area of Science:

• Polymer Chemistry
• Materials Science
• Organic Chemistry

Background:

• Covalent adaptable networks (CANs) offer dynamic properties due to dynamic covalent bonds (DCBs).
• Acetoacetyl chemistry provides a novel route to design DCBs for advanced materials.

Purpose of the Study:

• To investigate acetoacetyl formed amides (AFAs) as a new class of DCBs.
• To demonstrate the malleability and recyclability of polymer networks incorporating AFA linkages.
• To elucidate the mechanism behind AFA transamidation.

Main Methods:

• Utilized acetoacetyl chemistry to synthesize AFAs.
• Performed model studies and DFT calculations to understand the transamidation mechanism.
• Incorporated AFA linkages into cross-linked polymer networks.
• Tested mechanical properties and recyclability of the polymer networks.

Main Results:

• Established that AFA transamidation follows a "proton-switch" mechanism.
• Demonstrated significant malleability and recyclability of the AFA-based polymer networks.
• Confirmed no substantial mechanical changes or degradation after three recycling cycles.

Conclusions:

• Acetoacetyl formed amides are effective DCBs for creating robust CANs.
• Transamidation of AFAs is an efficient and economical method for CAN preparation.
• The developed CANs exhibit excellent durability and recyclability, suitable for sustainable materials.