We examine the vitrification and melting of asymmetric star polymer mixtures by combining rheological measurements with mode coupling theory. We identify two types of glassy states, a single glass, in which the small component is fluid in the glassy matrix of the big one, and a double glass, in which both components are vitrified. Addition of small-star polymers leads to melting of both glasses, and the melting curve has a nonmonotonic dependence on the star-star size ratio. The phenomenon opens new ways for externally steering the rheological behavior of soft matter systems.
Tailoring the flow of soft glasses by soft additives / Zaccarelli, Emanuela; C., Mayer; A., Asteriadi; C. N., Likos; Sciortino, Francesco; J., Roovers; H., Iatrou; N., Hadjichristidis; Tartaglia, Piero; H., Lowen; D., Vlassopoulos. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 95:26(2005), pp. 268301-1-268301-4. [10.1103/physrevlett.95.268301]