摘要：

We have recently developed a novel type of polymer network called slide-ring materials by using polyrotaxane, the supramolecular architecture with topological characteristics. In the network, polymer chains are topologically interlocked by figure-of-eight cross-links. Hence, these cross-links can pass along the polymer chains freely to equalize the tension of the threading polymer chains similarly to pulleys. Because the cross-linking junction can move in the polymer network, the structure and physical properties of the polymeric materials are drastically different from conventional cross-linked or noncross-linked materials. For instance, the slide-ring gel or elastomer shows quite small Young’s modulus, which is not proportional to the cross-linking density and much lower than those of chemical gels with the same density. This arises from the difference in the molecular mechanism of the entropic elasticity: While the conformational entropy is mainly responsible for the elasticity in usual chemical gels or rubbers, the mechanical properties of the slide-ring materials should be inherently governed by the arrangement entropy of free cyclic molecules in polyrotaxane as well as the conformational entropy of axis polymer. This means that the softness in the slide-ring gel is due to the novel entropic elasticity, which is also expected to yield sliding state and sliding transition. These properties are applied to top coating for cell phone and automobile as scratch-resist or self healing materials and to soft, resilient rubber and elastomer for soft actuators and abrasive materials.

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个人简介：

Kohzo Ito is a professor at t Graduate School of Frontier Sciences, The University of Tokyo. He received his B. E, M. E. and Ph. D. degrees in applied physics from the University of Tokyo. In 1986, he joined Research Institute of Polymers and Textiles in Tsukuba, Japan. He transferred back to The University of Tokyo in 1991. His research field includes polymer physics, soft matter physics, and supramolecular chemistry. At present, his group focuses on topological gel and slide-ring materials with freely movable cross-links. He is concurrently a director of Advanced Softmaterials Inc., which he founded to urge the application of the slide-ring materials in 2005. He has been the author of over 200 publications, including original research papers, reviews, and chapters of books, and over 50 patents. He also received The Award of the Society of Polymer Science, Japan (2006) and Grand Prize in University Corporate Relations for Creation (2006).