Abstract
[3] Polyrotaxane and its derivative having functionalized wheel components (abbr. : f- [3] polyrotaxane) were synthesized for the preparation of a polyrotaxane network using the f- [3] polyrotaxane as a polyrotaxane crosslinker. [3] Rotaxane, as a model of f- [3] polyrotaxane, having a crown ether as a wheel component and secondary ammonium salt as an axle component, was obtained in 82% yield according to the urethane end-capping protocol. f- [3] Polyrotaxane with a linear polymer axle was selectively synthesized according to the same protocol. The incorporation ratio of the crown ether was 84%. High yield synthesis of f-[3] polyrotaxane as a precursor of a tetrafunctional crosslinker was carried out using a crown ether wheel with protected reactive groups. The incorporation ratio of the wheel component reached ca. 80%. [3] Polyrotaxane crosslinker obtained by the deprotection gave the corresponding polyrotaxane network in 90% yield by the reaction with isocyanate-teminated polytetrahydrofuran. It was concluded that this type of [3] polyrotaxane crosslinker was quite useful for the synthesis of polyrotaxane networks.
