Stabilizing grafted colloids in a polymer melt: favorable enthalpic interactions

نویسندگان

  • Borukhov
  • Leibler
چکیده

The interactions between spherical colloids covered with end-grafted polymers (brushes) immersed in a polymer melt are studied theoretically. We show that attractive enthalpic interactions between the two polymer species, characterized by a negative Flory parameter (chi<0), can stabilize the colloidal dispersion. The stabilizing mechanism is a result of a structural change from a dry brush, where the melt chains do not penetrate deeply into the brush, to a wet brush, where the free chains penetrate the brush and force the grafted chains to extend into the melt.

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عنوان ژورنال:
  • Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics

دوره 62 1 Pt A  شماره 

صفحات  -

تاریخ انتشار 2000