Clickable Dialdehyde-Amine Polymerization (cDAP)

Synthetic polymers are important components of modern functional materials. Developing efficient polymerization processes with "clickable" features will enhance the diversity of available structures and facilitate exploration of new properties. In this work, we developed a strategy to synthesize isoindolin-1-one-based alternating copolymers through a new mode of step-growth polycondensation of functionalized bis-ortho-phthalaldehyde and diamine monomers. The reaction was performed in DMF and catalyzed by pyridine/AcOH at room temperature, affording linear copolymers with high molecular weights. This reaction enabled the production of alternating copolymers in a modular manner, where different functional units could be simply incorporated by varying the linker units in monomer structures. This approach was further expanded to synthesize branched and cross-linked polymer networks by introducing a triamine brancher and a dithiol cross-linker into the polymerization system. Some of the isoindolin-1-one-based copolymers behaved as thermoplastic elastomers, demonstrating the potential of this polymerization in materials sciences.