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Stabilizing Grafted Colloids in a Polymer Melt: Favorable Enthalpic Interactions

I. Borukhov·L. Leibler
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Abstract

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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I. Borukhov, L. Leibler. 2000-05-05. Stabilizing Grafted Colloids in a Polymer Melt: Favorable Enthalpic Interactions. https://doi.org/10.1103/physreve.62.r41

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