Systematic measurements of density, viscosity, and electrical conductivity on the ternary system water + ethanol + lithium chloride over entire ranges of solvent composition and LiCl solubility from (−5 to +50) °C have been carried out. The temperature-independent aquamolality scale, m (LiCl moles per 55.5 moles of solvent) has been used to justify data comparison not only at different temperatures but also for the solutions in various solvent mixtures. Density isotherms (fitted to second-order polynomials in m ) provided a composition-dependent density index, g(x 1), which can conveniently be used to determine the density at any desired LiCl concentration, mixture composition, and temperature. Excess molar volumes (V E) of the solvent mixtures have been calculated over the whole temperature range, and minima of all the V E isotherms at the same water mole fraction, x 1 = 0.6, suggest that no significant structural rearrangement takes place in the solvent mixtures upon temperature variation. From the density data, the “temperature average coefficient of thermal expansion” (β) is also determined for all the samples. Fitting the viscosity (η) isotherms to an extended Jones-Dole-type cubic equation in m provided coefficients related to various interactions taking place in the solutions. The temperature dependence of the entire η data can well be explained by the Arrhenius-type equation involving single flow activation energies (E a) that always increased with LiCl concentration for a given solvent but exhibited a sharper rise for the ethanol-rich mixtures; E a values tend to pass through maxima at x 1 ≈ 0.6. In all the cases, electrical conductivity (κ) plotted against m exhibits maxima which shift from 4.5 m to ∼6 m in the water-rich mixtures, and exhibition of the κ-maxima has been explained with a simple model according to which κ at any given m is comprised of two sets of the oppositely acting terms, namely κup and κdown. Since all the κ plots fit very well to third-order polynomials in m with negligibly small coefficients of the cubic terms, the other two terms involving m and m 2 can be compared with κup and κdown, respectively. From temperature variation of molar conductivity, activation energies have been determined and compared with those of viscous flow.

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Polymer composites are used in numerous applications. In spite of this fact, new developments are still under way to explore in other field of application of these materials and to tailor their properties for more extreme condition. A particular emphasis is focused on fillers content is summarized. Some steps towards the functionally graded materials are illustrated. The FT-IR spectroscopic studies revealed the information about curing of epoxy with fillers. It was observed that mechanical properties like tensile strength, hardness etc get enhanced up with filler contents. The effect of the different formulations were investigated and discussed for optimum process condition.

Methanol, unlike water, is miscible with 1-butanol in all proportions however not much work is available on binary mixtures of the two alcohols. Investigation of 1-butanol–methanol binary system (the mixture) can be interesting also for its general and industrial applications. In the present study densities over the entire composition range of the mixture have been measured from 293.15 to 308.15 K, which allowed determination of excess molar volume (V E) at four different temperatures. Structural information on the mixture has been obtained by adding sparingly soluble NaCl, KCl (borderline) and fairly soluble CdI2 (structure-breaker). Limited solubility of NaCl and KCl restricted the study only to their saturated solutions in the mixture. On the other hand using density data of CdI2 solutions of different molalities (from 4.0·10–3 to 8.0·10–2 mol·kg–1) in the mixture at the above temperatures, apparent molar (V Φ) and partial molal (V m°) volumes of CdI2 have been determined. The data also enabled determination of (α) a quantity related to the thermal expansion coefficient.

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