Stabilizing grafted colloids in a polymer melt: favorable enthalpic interactions
نویسندگان
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