Structure and Dynamics of Polyrotaxane and Mechanical Properties of Slide-ring Gels

Abstract

Polyrotaxane (PR) is a typical supramolecule, in which cyclic molecules are threaded onto a linear polymer chain. The cyclic molecules in PR can slide and rotate on the polymer chain. PR has been applied to a novel kind of polymer network, called “slide-ring (SR) gel”, which is prepared by cross-linking cyclic molecules belonging to different PRs. The cross-linking point of SR gels can slide along the polymer chains, and this unique structure causes the high extensibility of SR gels. We have investigated the structure and dynamics of PR at molecular level by contrast variation small-angle neutron scattering and neutron spin echo. The contrast variation methods allow us to elucidate the structure and dynamics of rings and polymers separately. Furthermore, we studied the macroscopic mechanical properties of SR gels and proposed a novel molecular theory for SR gels, which considered the alignment entropy of cyclic molecules on polymer networks.