Intrinsically Enhanced Polyimine Materials with Monomer-Recovery and High Overall Performance

Polyimine represents a new type of thermosetting material that possesses unique properties in self-healing, recyclability, and eco-friendliness led by the dynamic covalent interactions of imine bonds. However, polyimine films often exhibit poor mechanical properties and water resistance as imine bonds are prone to hydrolysis. A conjugated structure was formed to enhance the stability via the connection of benzene rings to the imine bonds. In this work, we have designed a series of polyimine materials with overall excellent properties by incorporating benzene rings on both sides of the C=N bond through a simple methodology. These materials demonstrate higher mechanical strength and hydrolysis resistance while the toughness could be adjusted through the introduction of flexible polyether amides. Furthermore, these imine materials can be completely depolymerized to monomers under mild conditions. This research presents a new approach that inherently enhanced polyimine materials while maintains flexibility and extensibility through straightforward and rational molecular design.