| Abstract
| - The phase behavior and structures of a poly(ethylene oxide-block-isoprene) diblock, having a volumefraction of poly(ethylene oxide), fPEO, of 0.64, have been determined as a function of polymer concentrationin water, and of temperature between 5 and 80 °C, using rheology and small/wide-angle X-ray scattering.Sol−gel boundaries were established by rheometry whereas small-angle X-ray scattering was employedto identify the lyotropic phases. For concentrations of diblock below 15 wt %, a liquid-like structure isobtained. Above 25 wt % copolymer in water, a lamellar morphology is observed which exhibits, for thepure sample, an order−disorder transition at 190 °C. Between these two concentrations a face-centeredcubic (fcc) structure is adopted. As the concentration of copolymer is increased in the fcc regime, the sizeof the spheres increases before to transform directly into a lamellar morphology.
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