Glass-forming microemulsions: Vitrification of simple liquids and electron microscope probing of droplet-packing modes

The recent development of microemulsion systems which do not separate during cooling and in which neither dispersed nor matrix phases crystallize during the cooling process permits low-temperature studies of the microemulsion structure and the investigations of common liquids in unusual states. Benzene, carbon tetrachloride, and CS₂ all can be supercooled without limit in microemulsion form, and their glass transition temperatures have been determined. Transmission electron microscopy of thin vitrified layers permits high-resolution observations of water-diluted samples of the same microemulsions. Gas-like, liquid-like and solid-like (hexagonal) organization of the microemulsion droplets are observed. Other experiments must decide which of these structures are imposed by the thin-film preparation technique and which are natural arrangements of warm bulk microemulsions.