Solvent solubility parameters

Solvent Solubility parameter 8 MPa % increase in weight in polymers ... 

Solvent Solubility parameter (S) (Hildebrands) Hydrogen bonding index (y) Relative evaporation rate (mPa s) Viscosity at 20 C... 

Solvent Solubility parameter (MPa1/2) Solvent Solubility parameter (MPa1/2)... 

Figure 5 The solubility parameter for PHEMA gel is about 31 MPa1/2. The swelling ratio decreases as the difference between the polymer and solvent solubility parameters increases. (From Ref. 109.)...

Solvent Solubility Parameter (cal/cm3) Dipole Moment Dt Dielectric Constant (e)t Solventtt Viscosity CP MTF PTF BTF ... 

Fig. 13. Effect of the solvent solubility parameter 8 on the linear coefficient of thermal expansion 3 (1) and modulus of elasticity E (2) of films of linear SBS thermoelastoplastics with 28.3% PS obtained from solutions. The solvent is indicated on the abscissa axis I — n-heptane, II — tetra-hydrofurane, III — benzene, IV — chlorobenzene 119)...

The solubility parameter is therefore a measure of the energy density holding the molecules in the liquid state. Note that regular solution theory can only predict positive AH. Thus, with this approach, prediction of solubility involves matching the solute and solvent solubility parameters as closely as possible to minimize AH. As a very rough mle of thumb 61 — 62 must be less than 2 (f/cm3)1 /2 for solubility. 

Lin and Nash (1993) have proposed an equation to estimate the Hildebrand solubility parameter of a solute strictly from its mole fraction solubilities and their respective solvent solubility parameters ... 

If this activity coefLcient term is applied to Equation 2.41, the mole fraction solubility can be shown to reach a maximum wh00i equals5D2, < pi equals, and< m equals - Teas (1968) presented a triangular plot where the sides represent the three contributions to the solvent solubility parameter. For example, the dispersion force contribution would be... 

Figure 3-17 Assignment of solvent solubility parameters to petroleum fractions.

Figure 14.23 Relationship between the critical strain of a polymer and the solvent solubility parameter. (From Ref. 24.)...

For the purpose of estimating the solubility of a solute it is necessary to have some measure of the polarity of a solute or a solvent. Based on Eqs. (1) and (2), a useful polarity index should be a measure of a material s intermolecular forces, Cn and C22-Table 1 contains a list of solvents that are typically used in liquid pharmaceutical formulations and three measures of solvent polarity. Each measure of solvent polarity, or polarity index, is based upon a different measure of a material s property. For example, dielectric constant is a measure of the electrical insulating properties of a solvent, solubility parameter is determined from the molar energy of vaporization, and... 

Polymer and solvent solubility parameters The most extensive compilation is provided in the recent book by Hansen and in the handbooks by Barton. - ... 

The Hansen method is very valnable. It has fonnd widespread use particularly in the paints and coatings indnstry, where the choice of solvents to meet economical, ecological, and safety constraints is of critical importance. It can explain cases in which polymer and solvent solubility parameters are almost perfectly matched, yet the polymer will not dissolve. The Hansen method can also predict cases where two nonsolvents can be mixed to form a solvent. Still, the method is approximate, it lacks the generality of a Ml thermodynamic model for assessing miscibility, and it requires some experimental measnrements. The determination of R is typically based on visnal observation of solubility (or not) of 0.5 g polymer in 5 cm solvent at room temperature. Given the concentration and the temperature dependence of phase boundaries, such a determination may seem a bit arbitrary. Still the method works out pretty well in practice, probably because the liquid-liquid boundaries for most polymer-solvent systems are fairly flat. ... 

Swelling in Pure Solvents. Table I shows the solvent uptake by Nafion-H. Figure 1, a plot of the solvent uptake for the 1200 EW sample against the solvent solubility parameter,, exhibits two distinct swelling envelopes. Apart from the presence of a sharp peak at 9.5 Hb, a broad peak spans from 12.8 to 23.4 Hb. They are denoted as envelopes I and II and have been tentatively ascribed to the organic backbone and the ion clusters of the membrane, respectively (3, 5). 

T,his work uses the solubility parameter concept to describe the solu- bility of a typical polyamide ink resin used in flexographic printing. The entire resin concentration solubility is described by coordinates of resin solubility concentration vs. solvent solubility parameter. An interpretation of the interaction between the dispersion force, dipole moment, and the hydrogen bonding force of the polyamide resin and industrially important alcohols is made from the data. 

Constants obtained by SXLSQI using the data shown in Fig. 7 up to [NaClO lmax. Pitzer parameters [168] and Masson coefficients [2 19] for sodium perchlorate used by SXLSQI were adopted assuming that the low concentration of solvent in the aqueous phase (see Table 11) has negligible effect on the aqueous ionic-activity and ion-volume properties. Solvent solubility parameters used by the program were taken from ref. [153]. Dielectric constants of the water-saturated solvents for use in the Debye-Hlickel treatment used in SXLSQI were 10.57 (TBP [220]), 13.63 (MIBK [221]), 17.5 (MIBC, estimated), and 37.4 (MeN02 [177]) the values for MIBC and MeN02 represent estimates based on an assumption of linear dependence of e on the volume fraction of water in the solvent. 

Shown in Figure 6 is a plot of the viscosity of samples 3 and 5 plotted as a function of temperature. The viscosities were measured using an Instron Capillary Rheometer at a shear rate of 450 sec, The extracted solvent solubility parameters for samples 3 and 5 were 8.46 and 8.79 respectively. Figure 6 shows that the... 

Shown in Figure 7 is a plot of the glass transition temperature of the different fractions plotted as a function of the extraction solvent solubility parameter. 

VARIATION IN C/H VS THE SOLVENT SOLUBILITY PARAMETER FOR VARIOUS CAT CRACKER BOTTOM PITCH FRACTIONS... 

VARIATION IN GLASS TRANSITION TEMPERATURE FOR EXTRACTED CAT CRACKER BOTTOM PITCH FRACTIONS AS A FUNCTION OF THE EXTRACTION SOLVENT SOLUBILITY PARAMETER... 

FIGURE 3 The dependences of macromolecular coil fractal dimension on polymer and solvent solubility parameters difference A5 for copolymers SAN-MMA. The solvents 1— toluene, 2—ethyl benzene, 3— benzene, 4—chlorobenzene, 5—chloroform, 6—tetrahydrofuran, 7—pyridine, 8—methyl ethyl ketone, 9-1,4-dioxane, 10—N, N-dimethylformamide. The same conventional signs are used in Figs. 4-11. 

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