Preparation of Tubular Polymers from Cyclodextrins

In recent years, polymers having unique structures, such as comb like polymers1, double helical polymers2, dendrimers3, and polymers with bilayer membranes structures4, have been prepared and attracted much attention because of their unique properties and functions. Much effort has been devoted to obtain other polymers with unique structures. In spite of strenuous efforts, tubular polymers have not been obtained until recently. Tubular polymers are ubiquitous in nature, especially in the living systems. Microtubules, flagella, and ion channels have tubular structures of various sizes. Tubular polymers in the living systems have various functions, not only as channels for membranes, but also as devices for mechanical movements. However, there have been no synthetic tubules made of organic materials of manometer size.