title: Structure of multi-component colloidal lattices at oil-water interfaces.
abstract: We have successfully assembled two-component S-PS/AS-PS (sulfate-treated polystyrene/aldehyde sulfate-treated polystyrene) and three-component S-PS/AS-PS/C-PS (sulfate-treated polystyrene/aldehyde sulfate-treated polystyrene/carboxylate-treated polystyrene) colloidal lattices at poly(dimethylsiloxane)-water interfaces. The colloidal particles assemble into long-range-ordered structure and oscillate around their equilibrium positions. Different types of particles distribute randomly in the lattice with no obvious phase separation. In the two-component colloidal lattices, the S-PS particles form mostly sixfold lattice sites, whereas the AS-PS particles largely form fivefold defect sites. The calculated attractive capillary force is stronger for the AS-PS particles, which likely explains their tendency to aggregate compared to the S-PS particles. In addition, we have performed total force calculation and extrapolated the surface charge densities of the particles in the oil phase.
authors.affiliation: Department of Chemical Engineering, Arizona State University, Tempe, Arizona 85287, USA.
authors.forename: Huan
authors.initials: H
authors.lastname: Ma
authors.forename: Lenore L
authors.initials: LL
authors.lastname: Dai
mesh_terms: D002264:Carboxylic Acids / Q000737:chemistry; D003102:Colloids / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D018613:Microscopy, Confocal; D009821:Oils / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry; D013431:Sulfates / Q000737:chemistry; D013499:Surface Properties; D014867:Water / Q000737:chemistry*
chemical_list: D002264:Carboxylic Acids; D003102:Colloids; D009821:Oils; D011137:Polystyrenes; D013431:Sulfates; D014867:Water