Equilibrium Janus Drop Topology. 2. A Single Drop in a Spherical Continuous Phase

• Published in: Journal of dispersion science and technology 2015-12, Vol.36 (12), p.1685-1692
• Main Author: Friberg, Stig E.
• Format: Article
• Language: English
• Subjects: Borders; Dispersions; Double emulsions; emulsions drop topology; interfacial equilibrium; interfacial tensions; Inversions; janus emulsions; Mathematical analysis; Nanoparticles; Topology; Unity
• ISSN: 0193-2691; 1532-2351
• DOI: 10.1080/01932691.2014.1003070

The equilibrium topology is analyzed of a single Janus drops of oils O1 and O2 in a spherical continuous aqueous phase, W, co-centered with O1. The radius of the O1 oil cap is equal to unity, while that of the oil O2 is varied and the cap centered individually. When the space of O2 exceeds the limit of W, the excess volume is discarded and the border surface of W is considered without interfacial energy. Earlier findings, when increasing the O2 on O1 coverage on a single Janus drop in an infinite aqueous phase, brought to light a selective O2 inversion from an emulsion (O1 + O2)/W to (O1 + W)/O2 at a well-defined surface coverage of O1 by O2. This specific inversion did not take place with the Janus drop in an aqueous phase of limited dimensions. Instead the inversion was perceived to take place, when the volume fraction of O2, V O2  = (V O1  + V w  + V O2 ) exceeded 0.5. The information from the earlier publication was used to calculate the variations of volumes V O2 and V W with the radius of the W sphere. The results partially contradicted earlier results.