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Updated: Mar 26, 2026

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Effect of Component Mobility on the Properties of Macromolecular [2]Rotaxanes
Zhen Chen1, Daisuke Aoki1,2, Satoshi Uchida1,2
1Department of Organic and Polymeric Materials, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8552, Japan.
Abstract:
Macromolecular [2]rotaxanes comprising a polymer axle and crown ether wheel were synthesized to evaluate the effect of component mobility on the properties of the axle polymer, especially its crystallinity. Living ring-opening polymerization of δ-valerolactone with a pseudorotaxane initiator with a hydroxy group at the axle terminus was followed by end-capping with a bulky isocyanate. This yielded macromolecular [2]rotaxanes (M2Rs) possessing polyester axles of varying molecular weights. The crystallinity of the axle polymers of two series of M2Rs, with either fixed and movable components, was evaluated by differential scanning calorimetry. The results revealed that the effect of component mobility was significant in the fixed and movable M2Rs with a certain axle length, thus suggesting that the properties of the axle polymer depend on the mobility of the polyrotaxane components.
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