Type I‐B Main‐Chain Polyrotaxane Network

Polyrotaxanes (PRs) are recognized for their outstanding conformational flexibility, making them ideal candidates for the design of high-performance mechanically interlocked materials. However, Type I-B main-chain PRs, featuring multiple wheels and stoppers along the polymer backbone, remain underexplored due to the challenges in their design and synthesis. Herein, we introduce a facile "host-guest recognition followed by click polymerization" strategy for the synthesis of Type I-B main-chain PR, which is subsequently employed to prepare the first-ever Type I-B main-chain PR network (PRN). Compared to the control whose wheels are nonslidable under applied force, the distinctive dynamic behaviors of Type I-B main-chain PR impart extraordinary mechanical enhancements to PRN, with fracture strain, toughness, and puncture resistance all surging by more than 27-fold. Moreover, the combination of the host-guest recognition and multiple stoppers endows the PRN with great self-recovery capability due to the restriction of the motion range of mechanical bonds. This work not only presents a novel strategy for designing and synthesizing Type I-B main-chain PR networks but also highlights the pivotal role of Type I-B main-chain PRs in enhancing material performance, offering valuable insights for advancing the development of dynamic polymer materials.