1,4-dioxane solubility parameter

The solubility parameter is about 19.2MPa and being amorphous they dissolve in such solvents as tetrahydrofuran, mesityl oxide, diacetone alcohol and dioxane. Since the main chain is composed of stable C—C and C—O—C linkages the polymer is relatively stable to chemical attack, particularly from acids and alkalis. As already mentioned, the pendant hydroxyl groups are reactive and provide a site for cross-linking. 

FIGURE 3 2 Solvent extraction efficiencies (EF) as functions of dielectric constants (D), solubility parameters (6), and polarity parameters (P and E -). Solvents studied silicon tetrachloride, carbon disulfide, n pentane. Freon 113, cyclopentane, n-hexane, carbon tetradiloride, diethylether, cyclohexane, isooctane, benzene (reference, EF 100), toluene, trichloroethylene, diethylamine, chloroform, triethylamine, methylene, chloride, tetra-hydrofuran, l,4 dioxane, pyridine, 2 propanol, acetone, ethanol, methanol, dimethyl sulfoxide, and water. Reprinted with permission from Grosjean. ... 

Besides showing the usefulness of the solubility parameter for the quantification of polarity, table 2.2 also illustrates the shortcomings of the model. On the basis of its solubility parameter alone, methylene chloride will be expected to behave quite similar to dioxane, and toluene similar to ethyl acetate. However, in both cases there are considerable differences between the solvents in practice. For example, dioxane is miscible with water in all proportions, while methylene chloride is virtually insoluble in water. Clearly, to account for differences in behaviour between compounds of similar polarity a refinement of the model is needed. 

The interaction energy of the solute with the solvent is not expressed as the geometric mean of cpx and cp2, as shown in Equation (3.13), but as the polynomial power series of the solubility parameter of the solvent. The coefficients of the polynomial equation are determined experimentally by regression analysis. Figure 3.2 shows that the regressed (calculated) solubilities of caffeine in a mixture of water and dioxane are in good agreement with the experimental values. 

The order (1,4-dioxane > alcohol > hydrocarbon) is in agreement with the data reported by Mohlin and Gray (16). The solubility parameters (MPa) of cellulose and the organic vapors studied are ... 

Qualitatively MTBE Is estimated to have an overall solubility parameter value close to that of Indolene, but has higher polar and hydrogen bonding forces. As a result polar polymers such aa fluorocarbon, epichlorohydrin homopolymer and chlorosulfonated polyethylene tend to swell to a greater extent In MTBE rich mixtures, while nonpolar EPDM elastomer swells to a lesser extent In these mixtures. The very large swell of the fluorocarbon In MTBE Is not surprising since other ethers such as diethyl ether and dioxane are known to swell the fluorocarbon to a large extent [3]. 

Dioxane, ethylene glycol, water-soluble esters, and short-chain alcohols at high bulk phase concentrations may increase the CMC because they decrease the cohesive energy density, or solubility parameter, of the water, thus increasing the solubility of the monomeric form of the surfactant and hence the CMC (Schick, 1965). An alternative explanation for the action of these compounds in the case of ionic surfactants is based on the reduction of the dielectric constant of the aqueous phase that they produce (Herzfeld, 1950). This would cause increased mutual repulsion of the ionic heads in the micelle, thus opposing micellization and increasing the CMC. 

These solvents range in total solubility parameter from 8.65 to 12.14 (talji/2 with dispersive parameters ranging from 8.7 to 9.3. Solvents, such as DMF and acetaldehyde, show appreciable polar parameter while DMF and dioxane are strongly hydrogen bonded. MeCl,... 

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. 

The HPC could only with difficulty be washed off the particle surfece only those solvents which had solubility parameters close to that of polystyraie (such as ethoxyethanol) were effective in removing the stabilizer without at the same time dissolving the polystyrene particles completely. In this way, about 78% of the labelled stabilizer could be recovered. Gtx)d solvents for the HPC moiety (water and polar alo ols) removed less than 5% of the grafted stabilizo. Further proof that the stabilizer was irreversibly grafted came from the ct that when the stabilized particles woe dissolved in dioxane (a good solvent for all the components), the addition of methanol (a non-solvent for polystyrene) produced stable polystyrote particles once more. In comparison, when simple mixtures of polystyrene and HPC were treated in this way, coalescence occurred. 

Figure 3.27 Dependence of equilibrium swelling on the solubility parameter in a number of solvents (I) diethyl ether (11) diethylene glycol diethyl ether (III) butyl acetate (IV) ethyl acetate (V) tetrahydrofdran (VI) dioxane. Polyurethane networks based on PTMG and PPG mixture without additives (4) and containing various KEP-2 mass fractions (1) 1.5 x 10 (3) 5 X 10- (2) 7.5 X 10- (5) 1.5 x 10 ...

The values a for seven polyarylates of different chemical structure, obtained by high-temperature (equilibrium) and interfacial polycondensation, determined in three solvents (sirmn-tetrachloroethane, tetrahydrofuran and 1,4-dioxane) are accepted according to the data of work [53]. The fractal dimension Dj. experimental values (o ) in the indicated solvents were determined according to the Eq. (4). The values of solubility parameter s for these solvents are taken from hterary sources [25, 36, 56]. The fractal dimension 5 of solvent molecules stracture was determined according to the equation [71] ... 

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. 

Equation 2.42 illustrates that the polymer and the solvent mix when their solubility parameters are close and do not when they differ a lot. However, this is not always the case. For instance, polyethylene and 1,4-dioxane have similar solubility parameters but do not mix partly because of crystallinity of polyethylene. Poly(methyl methacrylate) dissolves well in tetrahydrofuran, although the solubility parameters are greatly different. Furthermore, Eq. 2.42 is always positive. It fails to describe specific interactions that may make x negative such as the hydrogen bonding. We should regard Eq. 2.42 as one of the possible ways to describe x for some polymer-solvent systems. 

Product specifications for some typical commercial grades of poly(vinyl formal) are given in Table 5.2. As the formal content increases there is a progressive increase in softening point, impact strength and hardness. The materials, being amorphous, are soluble in solvents of similar solubility parameter, such as dichloroethylene and dioxan as the acetate content increases, the polymers become more soluble in ketones, esters and glycol ethers. 

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