Physical properties of ring polymers and their derivatives

Understanding of the properties of ring polymers is one of the central subjects in polymer physics. Thanks to the development in separation and purification techniques of ring polymers, highly-purified ring polymers could be prepared, and the studies on ring polymers have progressed. In this article, we briefly summarize recent discoveries of physical properties, especially viscoelastic properties, of ring polymers and their derivatives such as tadpole-shaped polymer and dumbbell-shaped polymer.