Synthesis and properties of rotaxane-cross-linked polymers using a double-stranded γ-CD-based inclusion complex as a supramolecular cross-linker

A vinylic supramolecular cross-linker (VSC) was prepared from gamma-cyclodextrin (gamma-CD) and a macromonomer for the purpose of simple and easy introduction of rotaxane cross-links into polymers via the radical polymerization of vinyl monomers. The synthesis of VSC as a pseudocross-linked cross-linker was performed by the simple mixing of gamma-CD and a poly(ethylene glycol)-based terminal-bulky macromonomer in water. The radical polymerization of typical vinyl monomers such as N, N-dimethyl acrylamide in the presence of the VSC afforded the corresponding rotaxane cross-linked polymers (RCPs) under both photoinitiated and redox polymerization conditions. In particular, RCPs exhibited mechanical properties endowed by the rotaxane cross-links that were superior to those of chemically cross-linked polymers, demonstrating the significant usefulness of the VSCs. (C) 2017 Elsevier Ltd. All rights reserved.