Interplay of polymer crystallization and liquid-liquid demixing in solutions studied by lattice-model theory and simulations

نویسندگان

  • Wenbing Hu
  • Daan Frenkel
  • Mark Miller
  • Vincent B. F. Mathot
چکیده

We report dynamic Monte Carlo simulations and statistical thermodynamic theories of a lattice-polymer model, in which polymer crystallization and liquid-liquid demixing of semiflexible homopolymer solutions were investigated simultaneously. In our simulations, the equilibrium phase transition temperature was approached by the onset of phase transitions on cooling, when an introduced substrate greatly decreased the kinetic delay caused by the homogeneous nucleation. The simulation results about the phase transition temperatures and their shift due to the interplay of phase transitions showed good agreement with the predictions of mean-field theories. In addition, upon cooling through the monotectic triple point in a concentrated solution, our simulation found that liquid-liquid demixing is kinetically favored over crystallization in the competitation of homogeneous nucleations.

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تاریخ انتشار 2008