2-methyl-1 -propanol surface tension

The surface tension of binary mixtures of water + monoethanolamine and water + 2-amino-2-methyl-l-propanol and tertiary mixtures of these amines with water from 25 to 50°C have been reported. = The surface tension of aqueous solutions of diethanolamine and triethanolamine from 25 to 50°C have been analyzed. ... 

Here Y denotes a general bulk property, Tw that of pure water and Ys that of the pure co-solvent, and the y, are listed coefficients, generally up to i=3 being required. Annotated data are provided in (Marcus 2002) for the viscosity rj, relative permittivity r, refractive index (at the sodium D-line) d. excess molar Gibbs energy G, excess molar enthalpy excess molar isobaric heat capacity Cp, excess molar volume V, isobaric expansibility ap, adiabatic compressibility ks, and surface tension Y of aqueous mixtures with many co-solvents. These include methanol, ethanol, 1-propanol, 2-propanol, 2-methyl-2-propanol (tert-butanol), 1,2-ethanediol, tetrahydrofuran, 1,4-dioxane, pyridine, acetone, acetonitrile, N, N-dimethylformamide, and dimethylsulfoxide and a few others. 

Fig. 8.6. Pure O2/N2 permeance ratio of asymmetric poly(phenylene oxide) membranes as a function of surface tension of chloroform/nonsolvent additives mixtures. Nonsolvent additives include 2-ethyl-l-hexanol (1m), 1-octanol (2m), 2-propanol (3d), 2-decanol (4m), 3,5,5-trimethyl-1-hexanol (5m), 2,4-dimethyl-3-pentanol (6d), 2,4,4-trimethyl-1-pentanol (7d), 2-methyl-3-hexanol (lOd), 3-ethyl-3-pentanol (12m), and 2-methyl-2-hexanol (13d). Merged is indicated by m discrete is indicated by d. Reprinted from [22], with kind permission from J.Tan...

For a mixture of low molecular constituents, n-propanol and u-nonane, it was observed not only negative deviation of surface tension from linear variation with composition, but also a minimum in surface tension (Gaman et al., 2005). Figure 6 shows variation of surface tension with composition of the mixture. Similar behaviour was found for the miscible blend of poly(methyl acrylate) (PMA) and poly(ethylene oxide) (PEO) (Pefferkometal., 2010). As far as the author is aware, this is first time that an extreme value for surface tension was found in a miscible polymer blend. The polymers used had number average molecular masses of A/ 5000 g/mol. Blends of PMA and PEO of those low molecular masses are completely miscible (Pedemonte and Buigisi, 1994). The Flory-Huggins interaction parameter was determined from PVT data io x 003 at 120 °C (Pefferkom et al., 2010). 

The addition of solvents will significantly lower the surface tension. Suitable solvents in general are low-boiling solvents miscible with water. Some examples are methanol, ethanol, 2-propanol, and 1-butanol as well as volatile water miscible ketones like methyl ethyl ketone. An example for a formulation containing 2-propanol is given in Table 10.3. As a drawback the addition of solvent may decrease the dispersion stability of the PEDOTrPSS-dispersion. A special conductivity enhancing effect of low volatile polar solvents will be discussed in Section 10.4.5 "Conductivity-Enhancing Additives."... 

In Figure 44, the use of 2-ethyl-l-hexanol, 1-octanol and 2-decanol as nonsolvent additives produces higher surface tensions resulting in higher pure O2/N2 permeance rate ratios. On the other hand, lower surface tensions resulting in lower pure O2/N2 permeance rate ratios are reflected in the use of 2-propanol, 2,4-dimethyl-3-pentanol, 2-methyl-3-hexanol and 2-methyl-2-hexanol as nonsolvent additives. 

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