The intrinsic dynamic feature of mechanically interlocked molecules (MIMs) has attracted great interest from polymer chemists, allowing them to explore various types of mechanically interlocked polymers (MIPs), such as polyrotaxanes and polycatenanes. However, almost all the previously reported methods to afford polyrotaxanes are uncontrolled and therefore unable to deliver materials with well-defined structures and narrow dispersity. Our group has recently developed a new method to synthesize polyrotaxanes in a controlled manner. Through ring-opening metathesis polymerization (ROMP) using a catenane as the selected monomer, we can produce polyrotaxanes with controlled molecular weights and narrow dispersity. The ratio of the threaded rings can also be regulated by the copolymerization of other norbornene-based monomers on account of the broad substrate scope of ROMP. Furthermore, we aim to harness this newly developed method to afford slide-ring networks (by crosslinking movable rings covalently) with a precisely controlled density of crosslinks, which is the key factor in modulating network performance and mechanical properties. This approach will provide access to various polymer networks formed by ROMP that are both tough and stretchable and, most importantly, shed light on the structure-property relationship between movable crosslinks and bulk materials. 

In this talk, recent advances from our group regarding the controlled synthesis of MIPs and our foray into slide-ring materials will be covered.