Mechanically Robust, Durable, and Multifunctional Hyper‐Crosslinked Elastomer Based on Metal–Organic‐Cluster Crosslinker: The Role of Topological Structure

Abstract Polymer materials formed by conventional metal‐ligand bonds have very low branch functionality, the crosslinker of such polymer usually consists of 2–4 polymer chains and a single metal ion. Thus, these materials are weak, soft, humidity‐sensitive, and unable to withstand their shape under long‐term service. In this work, a new hyperbranched metal–organic cluster (MOC) crosslinker containing up to 16 vinyl groups is prepared by a straightforward coordination reaction. Compared with the current typical synthesis of metal–organic cages (MOCs) or metal–organic‐polyhedra (MOP) crosslinkers with complex operations and low yield, the preparation of the MOC is simple and gram‐scale. Thus, MOC can serve as a high‐connectivity crosslinker to construct hyper‐crosslinked polymer networks. The as‐prepared elastomer exhibits mechanical robustness, creep‐resistance, and humidity‐stability. Besides, the elastomer possesses self‐healing and recyclability at mild condition as well as fluorescence stability. These impressive comprehensive properties are proven to originate from the hyper‐crosslinked topological structure and microphase‐separated morphology. The MOC‐driven hyper‐crosslinked elastomers provide a new solution for the construction of mechanically robust, durable, and multifunctional polymers.