title: Macromolecular recognition and macroscopic interactions by cyclodextrins.
abstract: Herein macromolecular recognition by cyclodextrins (CDs) is summarized. Recognition of macromolecules by CDs is classified as main-chain recognition or side-chain recognition. We found that CDs form inclusion complexes with various polymers with high selectivity. Polyrotaxanes in which many CDs are entrapped in a polymer chain were prepared. Tubular polymers were prepared from the polyrotaxanes. CDs were found to recognize side-chains of polymers selectively. CD host polymers were found to form gels with guest polymers in water. These gels showed self-healing properties. When azobenzene was used as a guest, the gel showed sol-gel transition by photoirradiation. When ferrocene was used, redox-responsive gels were obtained. Macroscopic self-assembly through molecular recognition has been discovered. Photoswitchable gel association and dissociation have been observed.
authors.affiliation: Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Osaka, 560-0043, Japan. harada@chem.sci.osaka-u.ac.jp.
authors.forename: Akira
authors.initials: A
authors.lastname: Harada
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Takashima
keywords: cyclodextrins; macroscopic self-assembly; polymers; rotaxanes; switching materials