Depletion-Driven Phase Separation and Reversible Aggregation in Confined Colloidal Mixtures
Erik K. Hobbie
The kinetics of depletion-driven size segregation in confined binary mixtures of nearly-hard-sphere colloids are studied with video microscopy. During the transient fluid-fluid phase separation that occurs as an intermediate step in the formation of isolated large-sphere-crystallites, the structure factor of the (larger)minority component exhibits a spinodal-like evoluation, while the cluster-size distribution exhibits scaling reminiscent of colloidal aggregation. The scaled distributions show a crossover from power-law (x1) behavior, where x=k/s is the ratio of cluster-size index to average cluster size. A phenomenological explanation based on the reversible Smoluchowski equation is proposed.
Depletion-Driven Phase Separation and Reversible Aggregation in Confined Colloidal Mixtures, Langmuir, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=851547
(Accessed June 10, 2023)