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The effect of polyethyleneglycol (PEG) on the phase behaviour of oil-rich sodium dodecyl sulphate, hexanol, water and dodecane mixtures has been investigated. PEG causes the disappearance of the `sponge' phase and induces the formation of a new isotropic phase, labelled L5 , located between the microemulsion, L2 , and the lamellar, L , phases. Small angle neutron scattering and electrical conductivity results show that at local scales the L5 phase consists of inverted bilayers, connected at larger scales. These features suggest a sponge-like structure for the L5 phase, a hypothesis which is further supported by a static and dynamic light scattering study.

We report a new hot-drawing process for treating wet-spun composite fibers made of single- and multiwall carbon nanotubes and poly(vinyl alcohol). As shown in previous reports, untreated composite nanotube fibers exhibit a very large strain-to-failure, and their toughness, which is the energy needed to break the fibers, exceeds that of any other known materials. However, untreated composite nanotube fibers absorb a very small amount of energy at low strain and become degraded in humid conditions. In this work, we use hot-drawing treatments, a concept inspired from textile technologies, to improve the properties of nanotube/PVA fibers. This treatment yields a crystallinity increase of the PVA and an unprecedented degree of alignment of the nanotubes. These structural modifications lead to a markedly improved energy absorption at low strain and make the fibers resistant to moisture. Hot-drawn nanotube/PVA fibers hold great potential for a number of applications such as bulletproof vests, protective textiles, helmets, and so forth.