Construction of polyrotaxanes via reversible chain exchange between acylhydrazone bonds

By simply heating mixtures of alpha-cyclodextrins and dumbbell-like poly(ethylene glycol) derivatives at 120 degrees C, polyrotaxanes form spontaneously via reversible chain exchange between acylhydrazone bonds, which have been proven by analyses of diffusion-ordered NMR, WAXD, 1H NMR, solid-state 13C CP/MAS NMR, DSC and UV-Vis together.