Monodisperse emulsion generation via drop break - o in a co - owing stream

We describe an experimental technique for the production of highly monodisperse emulsions (with minimum achievable polydispersities < 3%). The phase to be dispersed is introduced into a coowing, surfactant laden continuous phase via a tapered capillary. Drops detach from the capillary when the streamwise forces exceed the force due to interfacial tension. Drop size is a function of the capillary tip diameter, the velocity of the continuous phase, the extrusion rate, and the viscosities and interfacial tension of the two phases. Emulsions composed of a variety of uids and with drop sizes ranging from 2-200 m have been produced using this technique. PREPRINT: submitted to Langmuir Typeset using REVTEX Electronic address: [email protected]