title: Stabilization of Pickering Emulsions with Oppositely Charged Latex Particles: Influence of Various Parameters and Particle Arrangement around Droplets.
abstract: In this study we explore the fundamental aspects of Pickering emulsions stabilized by oppositely charged particles. Using oppositely charged latex particles as a model system, Pickering emulsions with good long-term stability can be obtained without the need for any electrolyte. The effects of parameters like oil to water ratio, mixed particle composition, and pH on emulsion type and stability are explored and linked to the behavior of the aqueous particle dispersion prior to emulsification. The particle composition is found to affect the formation of emulsions, viz., stable emulsions were obtained close to a particle number ratio of 1:1, and no emulsion was formed with either positively or negatively charged particles alone. The emulsions in particle mixtures exhibited phase inversion from oil-in-water to water-in-oil beyond an oil volume fraction of 0.8. Morphological features of emulsion droplets in terms of particle arrangement on the droplets are discussed.
authors.affiliation: Polymer Engineering and Colloid Science Lab (PECS), Department of Chemical Engineering, Indian Institute of Technology Madras , Chennai - 600036, Tamilnadu, India.
authors.forename: Trivikram
authors.initials: T
authors.lastname: Nallamilli
authors.affiliation: Surfactant & Colloid Group, Department of Chemistry, University of Hull , Hull HU6 7RX, United Kingdom.
authors.forename: Bernard P
authors.initials: BP
authors.lastname: Binks
authors.affiliation: Polymer Engineering and Colloid Science Lab (PECS), Department of Chemical Engineering, Indian Institute of Technology Madras , Chennai - 600036, Tamilnadu, India.
authors.forename: Ethayaraja
authors.initials: E
authors.lastname: Mani
authors.affiliation: Polymer Engineering and Colloid Science Lab (PECS), Department of Chemical Engineering, Indian Institute of Technology Madras , Chennai - 600036, Tamilnadu, India.
authors.forename: Madivala G
authors.initials: MG
authors.lastname: Basavaraj
mesh_terms: D004655:Emulsions / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D009821:Oils / Q000737:chemistry; D010316:Particle Size; D011137:Polystyrenes / Q000737:chemistry*; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D004655:Emulsions; D009821:Oils; D011137:Polystyrenes; D014867:Water