Solid-State Dynamics, Phase Structure, and Properties of Rotaxanated Polymers

Georgia Tech Research Corporation, Atlanta GA

Investigators

Abstract

Rotaxantated polymers will be examined with a variety of analytical techniques to establish structure/mobility/property relationships for this class of materials. Two types of polyrotaxanes are described based on very different macrocyclic components: (1) crown ethers, and (2) cyclodextrins. In crown-ether-based rotaxanated polymers, the macrocycle is typically more mobile than the host backbone. In cyclodextrin-based rotaxanated polymers, the macrocycles form rigid hydrogen-bonded tunnels inside which the linear polymer backbones can exhibit greater mobility than when not threaded. The consequences of these dynamic architectures on bulk physical properties will be explored and compared. In particular, impact strength and microphase separation will be investigated for a series of crown-ether-based rotaxanated polymers as a function of macrocycle loading. Two novel constructions will be prepared and evaluated from the rotaxanation of linear polymers with cyclodextrins: (1) articulated structures of rotaxanated and nonrotaxanated chain segments, and (2) threaded crosslinking. Thermal and mechanical properties will be correlated with information on solid-state dynamics and phase structures obtained through solid-state NMR, x-ray scattering, and electron microscopy. This research is in the area of characterization of novel polymeric and organic materials.