The frequency- and temperature-dependent conductivity of our polycrystalline perovskite ceramic systems with a composition of Ba0.97La0.02Ti1−xNb4x/5O3 (x = 5, 7 and 10, in mol%) was investigated.

The self-assembly behaviour of poly(ethylene oxide)-b-poly(propylene oxide)-b-poly (ethylene oxide) copolymers, (EO) 13 (PO) 30 (EO) 13 (Pluronic L64), and (EO) 70 (PO) 30 (EO) 70 (Pluronic F68) in water and in p-xylene has been elucidated by using viscosity and dynamic light scattering measurements to investigate the effects of hydrophilic chains length on their conformational changes. The viscosity measurementswere performed for a range of temperature varying from 27 • C to 60 • C and concentration from 4 to 60 mg/ml. The variation of the viscosity and the conformational changes in aqueous solution depends on the kinds of interactions and the balance between excluded volume effects and hydrophobic interactions. Some dynamic light scattering measurements were also performed at room temperature for the same range of concentration to provide more information on the micellar structures in aqueous and organic solution.

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The rheological properties of Pluronic F68 were dissolved in various water/organic liquid mixtures over a wide range of temperatures, all at a concentration of 20 mg/mL. We have considered the following binary mixtures: Pluronic F68/water, F68/p-xylene, and F68/phenol. Various conformational transitions were detected and interpreted. We have also shown that these mixtures retain a Newtonian behavior independently of temperature and conformational changes. For ternary F68/p-xylene/water, F68/phenol/water, and F68/water/phenol mixtures, the behaviour of the solution is intimately related to the temperature and the amount of water and organic solvent added.