Solubility Parameter Of Solvent Research Articles

The Extraction of Tris(1,10-phenanthroline)ruthenium(II). I. Distribution Studies

Abstract Tris(1,10-phenanthroline)Ru(II) was extracted into various organic solvents with several anions, such as the perchlorate ion, the iodide ion, or the thiocyanate ion. The association constants of ion-pairs were successfully determined by analysis of the extraction curves in the solvents with low polarities. It was found that the ion-pairs were extracted mainly as the associated form and that only the first-step dissociation could slightly occur (<10−7) in such solvents; furthermore, the degree of association was considerable even in water. Therefore, the distribution ratio of the complex cation must be governed by both the hydration energy of the counter anion and the solubility parameter of the extraction solvent rather than its dielectric property. An abnormal decrease in the distribution ratio was observed when the tetraphenylborate ion was used as the counter anion. This phenomenon can be explained clearly in terms of the hydrotropism which was often encountered in the solution of an electrolyte with a large ion.

Polymerization of β‐carbomethoxypropionaldehyde

AbstractHigh molecular weight crystalline poly(carbomethoxyethyl)oxymethylene was prepared from β‐carbomethoxypropionaldehyde with the use of organometallic compounds. The characterization, fractionation, x‐ray analysis, and viscosity measurement were carried out. Degradation by hydrochloric acid gave a highly crystalline but soluble polymer of a lower molecular weight. It was interesting to note the high solubility character of the polymer in organic solvents in contrast to the poor solubility of the isomeric poly(acetoxyethyl)oxymethylene. From the relationship among the intrinsic viscosity, Huggins' constant, and the solubility parameter of solvent, the solubility parameter of the polymer was determined to be 9.3 (cal/ml)1/2.

Interactions in Poly(vinyl chloride) Solutions

Molecular weight–intrinsic viscosity relations for poly(vinyl chloride) in five solvents were measured. It was found that the unperturbed dimension of the polymer coil depends on the nature of the solvent. The double cluster integral, β, was computed for this polymer in 35 solvents assuming the statistical segment to be equivalent to the monomeric unit. Subtracting from β the polar interactions, βe, calculated from the theory of Yamakawa, et al., a correlation between βn=β−βe and the solvent solubility parameter δ1 was found to be similar to that of β=βn of nonpolar polymer–solvent systems. It has been found empirically that the data points can be separated into two relations; one for polymer–linear molecule solvents, and the second for polymer–non linear molecule solvents. It was demonstrated that this separation is consistent with the deficiency of the geometric mean rule of intermolecular interactions. This deficiency apparently originates in the “geometry” of the molecules, e.g., as expressed by the branching parameter l12 in the work of Funk and Prausnitz.

Solubilities and polymer‐solvent‐nonsolvent θ‐compositions of poly (di‐n‐alkyl itaconates)

AbstractIn order to establish the prerequisites for the examination of solution properties of poly(di‐n‐alkyl itaconates), the solubilities of the first 11 members of this polymer homologous series were determined in 70 solvents, and the results correlated with the lengths of the ester substituents of the polymer chain, the solvent solubility parameters and the solvent hydrogen bonding capacities. The relation between solvent strength and the lengths of ester substituents of the monomer units was established quantitatively for several solvents in terms of φ2 crit., the nonsolvent volume fraction in ternary polymer‐solvent‐nonsolvent θ‐mixtures, and evaluated according to a turbidometric titration method proposed by ELIAS1. Both groups of results are a guideline for the probable existance of θ‐conditions for particular polymer‐solvent pairs and permit the prediction of solubilities of still higher members of the series.

On the solubility parameter of polar polymers

AbstractThe binary cluster integral, β, was computed from intrinsic viscosity data. Subtracting from β the polar contribution, βe, calculated from YRCR theory,9 the nonpolar interaction parameter, βn, was found. The calculations were performed for poly(vinylacetate) and poly(methyl methacrylate), each in 16 solvents. The correlation between βn and the solvent solubility parameter, δ1, was found to be similar to that reported8,17 for solutions of natural rubber, cis‐polybutadiene and for poly(vinyl chloride). This correlation can be crudely approximated by the formula where E and F are functions of the ill‐defined symmetry of the solvent molecule and δm is the δ1 value for the local maximum of the function. At δ1 = constant, the more spherical is the molecule, the higher is the βn value. It was shown that for most cases separation of the solvent into two classes (linear and nonlinear) is sufficient. This βn behavior finds support in the Funk and Prausnitz6 report on aromatic–saturated hydrocarbon mixtures and in the theoretical calculations of Huggins.21,22

Temperature coefficient of gas solubility for regular solutions

AbstractA semi‐empirical method is reported for predicting the temperature coefficient of gas solubility for regular solutions. It appears to be capable of describing the temperature coefficient to an accuracy approaching that of the solubility measurements themselves. The method requires a knowledge of the solvent solubility parameter and critical temperature, as well as at least one solubility (at any temperature) of the gas in the particular solvent. New data for the solubilities of methane in hexane, heptane, octane, dodecane and hexadecane, over the temperature range (where possible) from O°C to 75°C along with a large number of previously published data are used to show the effectiveness of the proposed method.

Solubility Parameter of Selected Sulfonamides

This investigation was primarily concerned with the application of Hildebrand's solubility equation to the determination of the solubility parameter of selected sulfonamides. The vapor pressure of several selected solvent systems was determined by an isoteniscopic method. These data were used to calculate the solubility parameter of the mixed solvents. The heat of fusion of each sulfonamide was determined by differential thermal analysis. The solubility of the sulfonamides was measured in a series of solvent blends varying in polarity, and the solubility parameter of the sulfonamides was determined from their solubility data. An attempt was made to correlate the solubility parameter with the dielectric constant. The results were found to be linear with respect to the solvent blends of alcohol-water, alcohol-water-propylene glycol, water-glycerin, and dimethylacetamide-water-glycerin. Hildebrand's solubility concept appears to be a useful tool for predicting drug solubility where the solubility parameters of drug and solvent system are close to each other.

The hydration of butyric acid in organic solvents

Hydration of n-butyric acid has been studied in benzene, toluene, chlorobenzene, nitrobenzene, 1,2-dichloroethane, and carbon tetrachloride. The hydration of the acid monomer is given by the following equation: HR (0) + 2H 2O (0) ▪HR·2H 2O (0) The hydration constant K h is: 85±20 for benzene, 190±20 for toluene, 70±30 for chlorobenzene, 25±5 for nitrobenzene, 27±5 for 1,2-dichloroethane, and 1080±150 for carbon tetrachloride. The distribution coefficient of the monomer dihydrate of carboxylic acid is related to the solubility parameter of the organic solvent. A linear relationship is observed between the hydration constant and the dimerization constant of the carboxylic acid.

Relation between distribution of TTA and “solubility parameter” of alcohol solvent

The distribution of thenoyltriftuoroacetone (TTA) between 11 alcohols and the aqueous perchlorate solution of ionic strength of 0·1 was studied at 25°C. Though a peculiar distribution curve of TTA was observed in the higher pH region, an equilibrium among TTA species in the organic phase is independent of hydrogen ion concentration in the aqueous phase below pH 4. There is a good correlation between the distribution coefficient of TTA and the so-called solubility parameter of alcohol solvent, and the details of this correlation are discussed.

Practical evaluation of the [η]–M relationship. III. Estimation of the exponent a

AbstractA method is proposed for predicting the exponent a of the Mark‐Houwink equation, [η] = KMa. This method makes use of the solubility parameters of polymer and solvent.

Some physical properties of soap/solvent systems and their relation to the solubility parameter of the solvent

Certain solubility-linked physical properties of soap/solvent systems have been shown to be functions of the solubility parameter of the solvent. The lowest critical solution temperatures for zinc and lead stearates occur in solvents having a solubility parameter of 8.9. Maximum swelling of lithium and sodium stearate/solvent systems occurs at a solvent solubility parameter of 9.3. In addition, the gel/jelly-sol transition temperatures for aluminum dilaurate/solvent systems have been shown to be an approximately linear function of solvent solubility parameter. A qualitative explanation for the observed results is based upon an analogy to high polymer/solvent systems.

Lubrication and wear in space systems

The solvent flux was measured in binary mixtures of ethanol and n-hexane for nine solvent-stable polymeric membranes in range of reverse osmosis (RO) to ultrafiltration (UF) (GE AK Osmonics, Dow 102326, GE DK Osmonics, MPF-34, STARMEM™ 122, STARMEM™ 240, NF30, NTR7450, NF-PES-010). GC-analyses of feed and permeate samples showed a separation factor close to 1, which indicates the solvent transport occurs by convection or by coupled diffusion through the membranes. The effect of viscosity, surface tension, di-electric constant and solubility parameter of solvent on permeation rate was studied for four categories of membranes, i.e. RO membranes, dense nanofiltration (NF) membranes, semi-porous NF membranes and micro-porous NF membranes. While viscosity seems to be a main transport parameter (similar composition of feed and permeate), higher fluxes of ethanol compared to n-hexane (with lower viscosity) confirmed that the transport may occur through coupled diffusion. The influences of the solvent–membrane interaction parameters such as surface tension, polarity and solubility parameters of solvent and membranes for dense membranes were investigated. The effect of solvent membrane interaction by means of solubility parameters was more pronounced compared to surface tension since the respective surface tensions of solvents are close to one another (γethanol=21.9,γn‐hexane=17.9). Partial permeabilities were studied as well to evaluate the influence of each component on permeation of the other. Unexpected results were observed for MPF-34, NF30 and NTR7450. Further investigation confirmed that their polymeric structure changed in contact with the solvents. Hydrophobic STARMEM™ membranes, which are expected to have a higher permeability for apolar solvents showed higher fluxes for ethanol compared to n-hexane. The similar solubility parameter of these membranes and ethanol may increase the permeation rate of ethanol molecules through membranes. For porous membranes viscosity was recognized as the key transport parameter, while affinity between membrane and solvent has a lower effect.

Manufacture of Simplex ferrochrome by the vacuum process: C G Chadwich, Trans 6 Vac Metall Conf, American VacuumSociety, 1964, 221–231.

The solvent flux was measured in binary mixtures of ethanol and n-hexane for nine solvent-stable polymeric membranes in range of reverse osmosis (RO) to ultrafiltration (UF) (GE AK Osmonics, Dow 102326, GE DK Osmonics, MPF-34, STARMEM™ 122, STARMEM™ 240, NF30, NTR7450, NF-PES-010). GC-analyses of feed and permeate samples showed a separation factor close to 1, which indicates the solvent transport occurs by convection or by coupled diffusion through the membranes. The effect of viscosity, surface tension, di-electric constant and solubility parameter of solvent on permeation rate was studied for four categories of membranes, i.e. RO membranes, dense nanofiltration (NF) membranes, semi-porous NF membranes and micro-porous NF membranes. While viscosity seems to be a main transport parameter (similar composition of feed and permeate), higher fluxes of ethanol compared to n-hexane (with lower viscosity) confirmed that the transport may occur through coupled diffusion. The influences of the solvent–membrane interaction parameters such as surface tension, polarity and solubility parameters of solvent and membranes for dense membranes were investigated. The effect of solvent membrane interaction by means of solubility parameters was more pronounced compared to surface tension since the respective surface tensions of solvents are close to one another (γethanol=21.9,γn‐hexane=17.9). Partial permeabilities were studied as well to evaluate the influence of each component on permeation of the other. Unexpected results were observed for MPF-34, NF30 and NTR7450. Further investigation confirmed that their polymeric structure changed in contact with the solvents. Hydrophobic STARMEM™ membranes, which are expected to have a higher permeability for apolar solvents showed higher fluxes for ethanol compared to n-hexane. The similar solubility parameter of these membranes and ethanol may increase the permeation rate of ethanol molecules through membranes. For porous membranes viscosity was recognized as the key transport parameter, while affinity between membrane and solvent has a lower effect.

Relation between the partition coefficient of GeX 4 molecules (X = Cl, Br, I) and the solubility parameter of the solvent

The extraction of germanium from HCl, HBr and HI acids solutions into 18 inert solvents has been studied. The determined distribution ratio has been correlated with the solubility parameter of the extracted GeX 4 molecule and with the solubility parameter of the inert solvent.

Relation between Partition Coefficients and Properties of Solvents

PUBLISHED data on the partition of non-electrolytes between water and different organic solvents are abundant ; but no successful attempt has been made to correlate the partition coefficients with the properties of solvents. No macroscopic property such as dielectric constant, refractive index or dipole moment can be correlated with partition coefficients in a simple manner. I have found the correlation between Hildebrand's solubility parameters of solvents and partition coefficients to be the most satisfactory.

Thermodynamic properties of solutions of cellulose derivatives. I. Dilute solutions of secondary cellulose acetate

AbstractOsmotic pressure of dilute solutions (c≤1.0 g./100 ml.) of a fraction from a secondary cellulose acetate in representative solvents have been measured at two or three temperatures. Number‐average molecular weights in acetone, aniline, methyl acetate, and pyridine do not vary with temperature but are significantly higher in methyl acetate in which association of polymer is possible. Molecular weights in acetic acid, nitromethane, and dioxane decrease with increase of temperature presumably because of degradation. Values of ΔF1, ΔH1, and ΔS1 have been estimated from temperature coefficients of osmotic pressure. All the systems are endothermal. It is suggested that the polymer is fully solvated and that solvated polymer and solvent mix with absorption of heat. With the exception of the aniline system, values for which are high, values of ΔH1 appear to be in the order to be expected from the solubility parameters of solvent and solvated polymer. ΔH1 and ΔS1 decrease with increase of temperature in all cases except that of acetic acid. ΔH1/ϕ, where ϕ2 is the volume fraction of polymer, seems to be effectively constant at each temperature. Values of ΔS1 are greater than “ideal” values but are less than those obtained for comparable systems containing more flexible and less polar polymers. ΔS1/ϕ decreases with increase of concentration but in some cases there is an increase at the highest concentration. ΔF1 becomes more negative with increase of temperature. It would seem that both entropy and heat terms contribute to the value of the interaction parameter χ1. It is possible, if solvation and the segment size and stiffness of chains are taken into account, that approximate lattice theories may apply to solutions of cellulose derivatives at lower concentrations than in cases of more flexible and less polar polymers.

Cellulose derivative‐solvent interaction

AbstractOsmotic pressure, initial phase separation, and viscosity results are presented for dilute solutions of cellulose nitrate, cellulose acetate, and ethyl cellulose, using polymers of similar molecular weight and degree of substitution. A fairly wide range of solvents has been used in each case. Osmotic pressure results suggest molecular dispersion of polymer in most solvents but there is evidence for association of ethyl cellulose in aromatic hydrocarbons. Values of the Huggins μ are obtained and, for systems involving cellulose nitrate and ethyl cellulose in homologous series of ketones and acetates, seem to fall to a minimum and then increase on ascent of each series. It is suggested that the heat term in μ should include an exothermic contribution arising from solvation in addition to an endothermic contribution resulting from mixing of solvated polymer and solvent. It is tentatively suggested that, in a homologous series of solvents, the entropy and exothermic contributions may not vary much and that the variation of μ may arise from varying endothermic contributions. The volumes of hexane required to cause initial phase separation of the nitrate and acetate from solution increase with solvent power, as estimated from μ, but with ethyl cellulose the volumes tend to decrease. It is suggested that solvated polymer may separate from solutions involving polar solvents and, making certain assumptions, estimates are made of the solubility parameters of the polymers separating. Those for cellulose nitrate vary markedly with solvent. The variation of solubility parameter with solvent is less with cellulose acetate and ethyl cellulose but in the latter case values for polymer separating from polar solvents are less than from nonpolar. Comparison of these estimated solubility parameters with those of the solvents and hexane suggests that the volumes of hexane required to cause initial phase separation will only serve as measures of solvent power if the solubility parameters of solvents and precipitant all lie on the same side of that of the polymer separating. This seems to be so for cellulose acetate and possibly the nitrate but not for ethyl cellulose. Comparison of viscosity parameters and values of μ suggests that in certain cases both [η] and the initial slope of the plot of ηsp/c against c increase with solvent power. Other suggested viscosity measures of solvent power do not seem to be generally applicable. Some variation of chain configuration with solvent seems probable. Solvation, solvent type and association of polymer may also affect the viscosities of dilute solutions of cellulose derivatives.