Multifunctional Polysiloxane with coordinative ligand for ion recognition, reprocessable elastomer, and reconfigurable shape memory

Incorporating supramolecular motifs into polysiloxanes has been attracting interest to thrive advanced materials with unprecedented properties, such as enhanced stiffness, high stretchability, self-healing ability, and interfacial adhesion. Herein, we designed and synthesized a novel coordinative polysiloxane functionalized with the 2-hydroxy-1-naphthyl imine group, featuring in the synergistic coordination of N and O atoms towards various metal ions. By making full use of its coordination ability, this novel polysiloxane has been utilized for multipurpose applications. Firstly, remarkable ion recognition ability for Fe3+, Zn2+ and Al3+ ions was demonstrated. Secondly, supramolecular elastomers with thermoplasticity and self-healing ability were prepared by coordinating this polysiloxane with various metal ions. Especially the P1-10%-Fe3+ elastomer exhibits unprecedented mechanical strength (8.8 MPa) and fracture toughness (33.22 MJ/m3) among the reported thermoplastic polysiloxane-based elastomers. Thirdly, reprocessable shape-memory materials were developed by combination of glass transition and topological rearrangement induced by temperature, expanding their potential for complex reversible shape shifting. This new type of polymer could open the door for wider applications of supramolecular polysiloxane materials.