Dichloromethane solubility parameter

The static mode uses both organic solvents such as toluene [27], methanol [28] or acetone [29] and solvent mixtures (usually in a 1 1 ratio) including dichloromethane-acetone [20,28], acetone-hexane [30,31], heptane-acetone [31], acetone-isohexane [32] or methanol-water [33], The use of mixed solvents as extractants provides improved extraction in terms of expeditiousness and recovery [20,28,30-35] as a result of the solubility parameter for a binary mixture being roughly proportional volumewise to the parameters of its components [36], Thus, in the extraction of Irganox 1010 from polypropylene, the addition of 20% of cyclohexane to 2-propanol doubles the extraction... 

An understanding of the solubility of polysulfones is important for applications in which the polymer must be dissolved, such as in coatings and membrane applications. Solubility of the three commercial polysulfones follows the order PSF > PES > PPSE All three polysulfones can be dissolved in a small number of highly polar solvents to form stable solutions at room temperature. NMP, DMAc, pyridine, and aniline are suitable solvents for polysulfones. Also 1,1,2-trichlorethane and 1,1,2,2-tetrachloroethane are suitable but are unattractive for health reasons. Because of the lower solubility parameter of PSF, it can also be dissolved in several less polar solvents such as tetrahydrofuran (THF), 1,4-dioxane, chloroform, dichloromethane, and chlorobenzene. Solvent choices for PES and PPSF are fewer because these polymers have a propensity to undergo solvent-induced crystallization in many solvents. 

More interesting examples are PVC and the polycarbonate of bis-phenol A - both slightly crystalline polymers. It is noticed here that while dichloromethane is a good solvent and tetrahydrofuran a poor solvent for the polycarbonate, the reverse is true for PVC, yet all four materials have similar solubility parameters. It would seem that the explanation is that a form of hydrogen bonding occurs between the polycarbonate and methylene chloride and between PVC and tetrahydrofuran. In other words, there is a specific interaction between each solvent pair ... 

In this work preliminary vapour permeation measurements were carried out with two different species, the rather bulky dichloromethane (DCM) molecules and the much smaller methanol molecules. Two typical permeation curves are displayed in Figure 4.8. The transport parameters, determined on the basis of the tangent method and Equations (4.9)-(4.11), are listed in Table 4.3. It contains the parameters dehned above as well as solubility C in the membrane in equilibrium with the feed pressure of penetrants. 

---