Cytoskeleton-Inspired Mechanically Interlocked Catenane Framework Enabling Robust yet Dynamic Polymer Networks.

Abstract

The red blood cell cytoskeleton, featuring a highly ordered yet dynamically reconfigurable skeletal topology, offers an important structural inspiration for designing high-performance polymeric materials that integrate mechanical robustness, structural stability, and dynamic adaptability. Inspired by this topology and functionality, we report a class of dynamic polymer networks featuring a continuous mechanically interlocked catenane framework (^CFMIN). The catenane framework is constructed via a sequential self-assembly strategy, involving metal-coordination-driven formation of a supramolecular polyhexagonal network, followed by host-guest complexation with linear poly(crown ether). The resulting architecture integrates densely distributed mechanical bonds with a continuous rigid skeleton, thereby enabling simultaneous dynamic adaptability and structural stability. Compared with its structurally analogous but non-interlocked control, ^CFMIN demonstrates significantly improved stiffness, strength, and toughness. These enhancements arise from hierarchical force-triggered dynamic processes within catenane framework, involving host-guest dissociation, ring sliding, and metal-ligand bond rupture, together facilitating efficient energy dissipation. Meanwhile, topological constraints of catenane framework, along with robust metal coordination, impart superior structural stability to ^CFMIN, allowing network to retain integrity at temperatures up to 180°C. This work demonstrates that integrating mechanical bonds into ordered skeletal architectures offers a promising strategy for designing robust, dynamically adaptive, and thermally stable polymeric materials.