Novel Design of [c2]Daisy-Chain Rotaxane Crosslinkers Bearing Long-Chain Alkenes and Development of Tough Topological Polymer

To explore new possibilities in topological materials, we designed a tetrafunctional crosslinker composed of a [c2]daisy-chain rotaxane framework. In this study, a novel topological network polymer was successfully synthesized via an addition reaction between 3,6-dioxa-1,8-octanedithiol (DODT) and a tetrafunctional crosslinker, a [c2]daisy-chain rotaxane constructed from dibenzo-24-crown-8 ether (DB24C8) units and bearing long-chain alkenes on its four benzene rings. The resulting network polymer exhibited both high stiffness and toughness, along with excellent shape-memory properties. These characteristics were governed by a balance between plastic and elastic deformation originating from the DODT and rotaxane domains, respectively, highlighting a new design strategy for the creation of advanced topological materials.