Large ultrathin shelled drops produced via non-confined microfluidics.
We present a facile approach for producing large and monodisperse core-shell drops with ultrathin shells using a single-step process. A biphasic compound jet is introduced into a quiescent third (outer) phase that ruptures to form core-shell drops. Ultrathin shelled drops could only be produced within a certain range of surfactant concentrations and flow rates, highlighting the effect of interfacial tension in engulfing the core in a thin shell. An increase in surfactant concentrations initially resulted in drops with thinner shells. However, the drops with thinnest shells were obtained at an optimum surfactant concentration, and a further increase in the surfactant concentrations increased the shell thickness. Highly monodisperse (coefficient of variation smaller than 3 %) core-shell drops with diameter of ∼200 μm-2 mm with shell thickness as small as ∼2 μm were produced. The resulting drops were stable enough to undergo polymerisation and produce ultrathin shelled capsules.
Department of Physics, King's College London, Strand, London, WC2R 2 LS (UK).
Ankur S
AS
Chaurasia
Dimitris N
DN
Josephides
Shahriar
S
Sajjadi
D002214:Capsules / Q000737:chemistry*; D044085:Microfluidics; D013500:Surface Tension; D013501:Surface-Active Agents / Q000737:chemistry*
D002214:Capsules; D013501:Surface-Active Agents
colloids; interfaces; microfluidics; millimetric droplets; ultrathin shells