Formation of colloidal clusters and chains at the air/water interface

Further to the reported formation of 2-dimensional foam and cluster structures of latex colloidal particles at the air/water interface, a detailed analysis and interpretation are presented about the cluster formation and the equilibrium cluster size. Many cell walls within the foam structure are formed by a single row of colloidal particles (a colloidal chain), whose stabilization by particles with only isotropic interactions is remarkable. It is proposed that a colloidal chain can exist in a system of purely isotropic interactions, due to a long range stabilization arising from repulsive interactions.