Lyotropic Nematic Droplets of Single-Walled Carbon Nanotubes In Super Acids: Equilibrium Shape and Dynamics

The balance between surface tension, elastic energy and surface anchoring creates nematic droplets with elongated shape, called tactoids. Here we report equilibrium shape and coalescence dynamics of nematic droplets of single-walled carbon nanotubes (SWNTs) dissolved in superacids. We observe tactoids of different volume with a bipolar director field and uniform aspect ratio, which is different from tactoids observed in aqueous SWNTs solutions stabilized by surfactants. The coalescence dynamics of observed droplets is  affected by the elasticity of liquid crystalline state.  Coalescence proceeds by tangentially matching the nematic director of two drops. Also, we studied properties of nematic tactoids depending on the size distribution of SWNTs.