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[资源] Acc. Chem. Res.最新综述：环糊精与客体相互作用的超分子聚合物材料大阪大学原田明

Supramolecular Polymeric Materials via Cyclodextrin − Guest Interactions 共13页引文60篇
Akira Harada, * , † , ‡ Yoshinori Takashima,† and Masaki Nakahata†
†Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
‡Japan Science and Technology Agency (JST), Core Research for Evolutional Science and Technology (CREST), 7 Gobancho, Chiyoda, Tokyo 102-0076, Japan

Conspectus
Cyclodextrins (CDs) have many attractive functions, including molecular recognition, hydrolysis, catalysis, and polymerization. One of the most important uses of CDs is for the molecular recognition of hydrophobic organic guest molecules in aqueous solutions. CDs are desirable host molecules because they are environmentally benign and offer diverse functions.

This Account demonstrates some of the great advances in the development of supramolecular materials through host–guest interactions within the last 10 years. In 1990, we developed topological supramolecular complexes with CDs, polyrotaxane, and CD tubes, and these preparation methods take advantage of self-organization between the CDs and the polymers. The combination of polyrotaxane with αCD forms a hydrogel through the interaction of αCDs with the OH groups on poly(ethylene glycol). We categorized these polyrotaxane chemistries within main chain type complexes. At the same time, we studied the interactions of side chain type supramolecular complexes with CDs. In these systems the guest molecules modified the polymers and selectively formed inclusion complexes with CDs. The systems that used low molecular weight compounds did not show such selectivity with CDs. The multivalency available within the complex cooperatively enhances the selective binding of CD with guest molecules via the polymer side chains, a phenomenon that is analogous to binding patterns observed in antigen–antibody complexes.

To incorporate the molecular recognition properties of CDs within the polymer side chains, we first prepared stimuli-responsive sol–gel switching materials through host–guest interactions. We chose azobenzene derivatives for their response to light and ferrocene derivatives for their response to redox conditions. The supramolecular materials were both redox-responsive and self-healing, and these properties resulted from host–guest interactions. These sol–gels with built in switches gave us insight for creating materials that were self-healing or could serve as artificial muscle.

Furthermore, we developed another self-healing material with CD inclusion complexes that showed selective self-healing properties after its surface was cut. These CD self-healing materials do not include chemical cross-linkers; instead the inclusion complex of CDs with guest molecules stabilized the material’s strength. However, by introducing chemical cross-linkers into the hydrogels, we produced materials that could expand and contract. The chemical cross-linked hydrogels with responsive groups bent in response to external stimuli, and the cross-linkers controlled the ratio of inclusion complexes. Furthermore, we used the molecular recognition of CDs to achieve macroscopic self-assemblies, and this chemistry can direct these macroscopic objects into even larger aggregated structures. As we have demonstrated, reversible host–guest interactions have tremendous potential for the creation of a wide variety of functional materials.

Biography
Akira Harada earned his Ph.D. from the Department of Macromolecular Science at Osaka University in 1977. He has spent most of his career at the same university but has worked as a visiting scientist for IBM Research and as a postdoctoral researcher at Colorado State University. After working at the Institute of Scientific and Industrial Research (ISIR) at Osaka University, he has been a full Professor of Osaka University since 1998. He is now a Special Distinguished Professor at Osaka University
Biography
Yoshinori Takashima graduated from the Department of Macromolecules, Faculty of Fiber, Kyoto Institute of Technology, in 1998. He then moved to the Department of Macromolecular Science, Faculty of Science, Osaka University, and received his Doctorate of Science from Osaka University in 2003. Since 2004, he has been working at Osaka University as an Assistant Professor.
Biography
Masaki Nakahata graduated from the Department of Chemistry, Faculty of Science, Osaka University in 2010. He is currently working toward his Ph.D. at Osaka University. Since 2011, he has been supported by a JSPS fellowship from MEXT of Japan.

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