Authors: Anastassia N Rissanou Marianna Yiannourakou Ioannis G Economou Ioannis A Bitsanis
Publish Date: 2007/03/01
Volume: 46, Issue: 5, Pages: 755-764
Abstract
In this work we study the temperatureinduced development of “dynamically arrested” states in dense suspensions of “soft colloids” multiarm star polymers and/or blockcopolymers micelles by means of molecular dynamics MD simulations Temperature increase in marginal solvents results in “soft sphere” swelling dynamical arrest and eventually crystallization However two distinct “dynamically arrested” states were found one almost amorphous “glassy” and one with a considerable degree of crystallinity yet lower than that of the fully equilibrated crystal It is remarkable that even that latter state permitted selfdiffusion in the timescale of the simulations an effect that underlies the importance of the “ultrasoft” nature of interparticle potential The “number of connections” criterion for crystallinity proved to be very successful in identifying the ultimate thermodynamic trend from the very early stages of the αrelaxationFinancial support from the Greek Secretariat of Research and Technology under the “Collaborative Research Projects with Third Countries” program project HΠA010 is gratefully acknowledged The authors thank Prof D Vlassopoulos for many useful insights and discussions and Dr E Stiakakis for the generous supply of the experimental data on star hydrodynamic radii
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