In this paper, we reported a new technique for the preparation of a highly clear and transparent emulsified aqueous solution containing immiscible monomer (3,4-ethylenedioxythiophene, EDOT) droplets with diameters of a few tens of nanometers under surfactant-free conditions using tandem acoustic emulsification. The nanoemulsion prepared by this method was highly stable, even in the absence of surfactants. Furthermore, we demonstrated that the electropolymerization from the clear and transparent emulsified solutions containing EDOT nanodroplets enabled the formation of highly conductive transparent polymer (PEDOT) films. Appropriate sonication time length for each step and stability of the emulsions during the sonication steps were also systematically investigated in the tandem operation. (C) 2013 Elsevier Ltd. All rights reserved.