Volumetric Study of (3-Ethoxypropan-1-amine + Water) Mixtures between (283.15 and 303.15) K

Abstract

Experimental densities were obtained in the binary mixtures water + 3-ethoxypropan-1-amine, for the whole composition range and at temperatures between (283.15 and 303.15) K. Derived thermodynamic properties such as apparent molar, excess molar, and excess partial molar volumes have been calculated. Limiting partial molar volumes and isobaric expansions were obtained for the two components. Different patterns of molecular aggregation and hydration schemes were detected.

Volumetric Study of 3-Butoxypropan-1-amine + Water Mixtures between 283.15 and 303.15 K

“…This behavior is common to other water + amphiphile mixtures 5,7,8 and is probably ascribed to the hydrophobic moiety of the amphiphile. 8 Comparing this behavior to that of aqueous mixtures of EPA 9 (presenting two fewer methylene groups in the hydrophobic moiety of the amphiphile), it is noticeable that in the water + EPA system the minimums are preceded by maximums in the very-water-rich region. This feature may be justified by the hydrolysis that occurs to a greater extent in this system as compared to that in the system in study, and as will be shown just below, it is very slight in the case of BPA.…”

“…This procedure has often been used by us. [7][8][9]13,14 Statistical tools including F tests were used in order to optimize the number of A k (from k = 0 to 5) and B k (from k = 0 to 3) parameters to be used in each case. Experimental points at the two extreme temperatures, as examples, are shown in Figure 2, and calculated values are represented as full lines.…”

“…Also shown in the same figure is the T = 303.15 K isotherm for the system water (1) + EPA (2) for comparison. 9 A k and B k values, their standard deviations, and standard deviations of the fits are shown in Table 3.…”

“…As far as we know, only two thermodynamic studies are available in the literature embracing water + alkoxyamine systems, both carried out in our laboratory. 9,10 This time, the object of our study embraces aqueous mixtures of BPA with two more methylene groups than 3-ethoxypropan-1-amine (EPA) (previous studies), increasing the hydrophobic characteristics of the amphiphilic molecule.…”

“…In our group, we have been concerned with the thermodynamic study of water + amphiphile systems − aiming to get insight into molecular interactions focused on the effect of the hydrophobic/hydrophilic balance produced by changing either the chain length or the nature of hydrophilic functional groups. As far as we know, only two thermodynamic studies are available in the literature embracing water + alkoxyamine systems, both carried out in our laboratory. , This time, the object of our study embraces aqueous mixtures of BPA with two more methylene groups than 3-ethoxypropan-1-amine (EPA) (previous studies), increasing the hydrophobic characteristics of the amphiphilic molecule.…”