The novel morphology of rings was formed from the triblock copolymer in a dilute dioxane/water mixture solution. It gives an additional member to the crew-cut morphologies family.Wecan see that it is possible to formsomenovel morphology from the triblock copolymer in a dilute solution. In terms of the potential applications, it is conceivable that the rings may provide a template to fabricate nanocomposites because theP4VPblock can form a complex with a wide range of metal ions.42 The process of the morphological change from rods to vesicles and then to rings is interesting and attractive in itself. A better understanding of the process may shed light onto the structural changes and assembly in biological cells.