String model for the dynamics of glass-forming liquids.

نویسندگان

  • Beatriz A Pazmiño Betancourt
  • Jack F Douglas
  • Francis W Starr
چکیده

We test the applicability of a living polymerization theory to describe cooperative string-like particle rearrangement clusters (strings) observed in simulations of a coarse-grained polymer melt. The theory quantitatively describes the interrelation between the average string length L, configurational entropy Sconf, and the order parameter for string assembly Φ without free parameters. Combining this theory with the Adam-Gibbs model allows us to predict the relaxation time τ in a lower temperature T range than accessible by current simulations. In particular, the combined theories suggest a return to Arrhenius behavior near Tg and a low T residual entropy, thus avoiding a Kauzmann "entropy crisis."

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عنوان ژورنال:
  • The Journal of chemical physics

دوره 140 20  شماره 

صفحات  -

تاریخ انتشار 2014