Toluene solubility parameter

Tables 5.4 and 5.5 predict that unvulcanised natural rubber (8 = 16.5) will be dissolved in toluene (8 = 18.2) and in carbon tetrachloride (8 = 17.5) but not in ethanol (8 = 26.0), all values being in units ofMPa. This is found to be true. Similarly it is found that there is a wide range of solvents for polystyrene in the solubility parameter range 17.2-19.7 MPa. ...

The solubility of commercial poly(methyl methacrylate) is consistent with that expected of an amorphous thermoplastic with a solubility parameter of about 18.8 MPa. Solvents include ethyl acetate (8 = 18.6), ethylene dichloride (8 = 20.0), trichloroethylene (8 = 19), chloroform (8 = 19) and toluene (8 = 20), all in units ofMPa. Difficulties may, however, occur in dissolving cast poly(methyl methacrylate) sheet because of its high molecular weight. 

Being a hydrocarbon with a solubility parameter of 18.6MPa - it is dissolved by a number of hydrocarbons with similar solubility parameters, such as benzene and toluene. The presence of a benzene ring results in polystyrene having greater reactivity than polyethylene. Characteristic reactions of a phenyl group such as chlorination, hydrogenation, nitration and sulphonation can all be performed with... 

The solubility parameters of PCL are 20.8 and 20.4 jl/2.cm"2 2 when calculated using the parameters of Fedors and Hoy, respectively (58). PCL is soluble in a number of solvents at room temperature, including THF, chloroform, methylene chloride, carbon tetrachlornie, benzene, toluene, cyclohexanone, dihydropyran, and 2-nitropropane. 

Absorption rates of carbon dioxide were measured in organic solutions of glycidyl methacrylate at 101.3 kPa to obtain the reaction kinetics between carbon dioxide and glycidyl methacrylate using tricaprylylmethylammonium chloride(Aliquat 336) as catalysts. The reaction rate constants were estimated by the mass transfer mechanism accompanied by the pseudo-first-order fast reaction. An empirical correlation between the reaction rate constants and the solubility parameters of solvents, such as toluene, A-methyl-2-pirrolidinone, and dimethyl sulfoxide was presented. 

The rate constants in organic reaction in a solvent generally reflect the solvent effect. Various empirical measures of the solvent effect have been proposed and correlated with the reaction rate constant [5]. Of these, some measures have a linear relation to the solubility parameter of the solvent. The logarithms of kj and k2/ki were plotted against the solubility parameter of toluene, NMP and DMSO[6] in Fig. 2. As shown in Fig.2, the plots satisfied the linear relationship. The solvent polarity is increased by the increase of solubility parameter of the solvent. It may be assumed that increase of unstability and solvation of Ci due to the increase of solvent polarity make the dissociation reaction of Ci and the reaction between Ci and COisuch as SNi by solvation[7] easier, respectively, and then, k2/ki and ks increases as increasing the solubility parameter as shown in Fig. 2. 

The SEC mechanism demands only an isocratic (constant composition) solvent system with normally a single solvent. The most frequently used organic solvents are THF, chloroform, toluene, esters, ketones, DMF, etc. The key solvent parameters of interest in SEC are (i) solubility parameter (ii) refractive index (iii) UV/IR absorbance (iv) viscosity and (v) boiling point. Sample solutions are typically prepared at concentrations in the region of 0.5-5 mg mL-1. In general an injection volume of 25-100p,L per 300 x 7.5 mm column should be employed. For SEC operation with polyolefins chlorinated solvents (for detector sensitivity and increased boiling point) and elevated temperatures (110 to 150 °C) are required to dissolve olefin polymer. HFIP is the preferred solvent for SEC analysis of polyesters and polyamides. 

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. ... 

The incorporation of polar groups in unvulcanized polymers reduces their solubility in benzene. Thus the copolymer of acrylonitrile and butadiene (NBR), polychlorobutadiene (Neoprene), and fluorinated EP (the copolymer of ethylene and propylene) are less soluble in benzene and lubricating oils than the previously cited elastomers. Likewise, silicones and phosphazene elastomers, as well as elastomeric polyfluorocarbons, are insoluble in many oils and aromatic hydrocarbons because of their extremely low solubility parameters (silicons 7-8 H polytetrafluoroethylene 6.2 benzene 9.2 toluene 8.9 pine oil P.6). 

The solubility of PDMS in COo /toluene mixtures has been attributed to comparable solubility parameters and the interaction between CO2 (a weak Lewis acid) and the strong electron donor capacity of the siloxane group. The oxygen in perfluoropolyethers also has an electron donor capacity. The solubility parameter... 

From Hildebrand s solubility parameter, heptane is less polar than toluene, which in turn is less polar than methylene chloride, etc., to water, the most polar. Unfortunately, toluene and ethyl acetate exhibit similar 8 which does not account for their chemical properties moreover, Hildebrand s solubility parameters are not known for mixtures. 

FIGURE 2.2 Regularsolutiontheory plotfor hydrocortisone solubility data. The curve represents thesolubility predicted by Equation 2.41 using data frorhexane, cyclohexane, carbon tetrachloride, toluene, and benzene to estimate the solubility parameter of hydrocortisone. (Data taken from Hagen, T. A. 1979. With permission of the author.)... 

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. 

In another study Slobodian et al. (57) found that the percolation threshold for electrical conductivity of MWCNT-PMMA composites depends on the solvent used. The lowest percolation threshold was achieved for toluene where percolation was found to be at 4 wt% of MWCNT, for chloroform at 7 wt% and for acetone at 10 wt%. The highest conductivity was obtained at 20 wt% of MWCNT at values around 4x 10 5 Sc nr1 for composite prepared from toluene solution. They observed that the Hansen solubility parameters of individual solvent play an important role in the dispersion of MWCNT in PMMA. 

Slobodian et al. 2007(57) MWCNT Sun Nanotech Co. Ltd. Purified Solvent Casting Followed by compression molding CNT loading levels 2 to 20 wt% Bulk Composites Percolation threshold Solvent Percolation MWCNT Hansen solubility parameters were used as a guide to characterize percolation thresholds ... 

The oil structure influence on the formulation is illustrated in Figure 1. It represents the minimum percentage of emulsifiers required to induce the transition aacro-raicroeaulsion versus their HLB values for monomer-water mixtures dispersed in different oils. It can be seen that in the case of acrylamide (AH) or acrylamide-sodium acrylate (Aa) mixtures, the amount of surfactant needed to form a microemulsion is much larger for toluene or cyclohexane than for Isopar K (11,12[). When methacrylcxyethyltrimethylammonium chloride (HA0OU.AT) is the monomer, the optimal conditions are obtained in cyclohexane. These results closely follow the differences calculated for the solubility parameters between oils and lipophiles as shown in Table I. 

Carboxylic Groups Pervaporation separation of toluene/i-octane mixmres using copolyimide membranes containing 3,5-diaminobenzoic acid (DABA) was investigated in Ref. [128]. It was established that introduction of diaminobenzoic acid into the 6FDA-TrMPD polyimide improves membrane selectivity. The sorption component of the separation factor /3s is hnearly correlated with the membrane solubility parameter and with DABA content in the copolymer (/3s = 3.2, 3.3,4.3, 5.2 for DABA contents 0%, 10%, 33%, 60%, respectively). 

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... 

The solubililty parameters of the SMA copolymers selected for this study were calculated using the Small equation (31) or by titrating with more polar and less polar solvents. In this method, 1.0 0.02 g of polymer was dissolved in a known volume of toluene and a measured volume of methanol was added until a stable turbid system was produced. The procedure was repeated with n-heptane. The solubility parameter of the copolymer was then determined from the summation of the product of the volume of toluene and its solubility parameter and that of non-solvent and its solubility parameter. The average value of these titrations was used to obtain the upper and lower turbidity limits and the mean of these two values was used as the solubility parameter (32). 

The presence of a higher aromatic content In the gasoline resulted In Increased swell and hence Increased deterioration of tensile properties of elastomers exposed to the gasoline and Its mixtures. Addition of benzene to Increase the aromatic content resulted In slightly more detrimental effects on nitrile elastomers than the addition of toluene. The data on all elastomers can be explained In terms of the solubility parameter concept. 

A pump capable of several thousand p.s.i. commonly is used. Not only is the pump needed to maintain supercritical conditions, but the solubilizing power of the system varies greatly with pressure, usually dissolving more solutes as the pressure increases. For example, COj at 1.23 g/em will dissolve eompounds with Hildebrand s solubility parameter (Chapter 41, p. 479) from 7-10, about the same as benzene, chloroform, ethyl acetate, acetone, cyclohexane, carbon tetrachloride, toluene, ethyl ether, and pentane. If the pressure is reduced so that the COj is about 0.9 g/cm then it will dissolve compounds with parameters from 7-9 (solvents like cyclohexane, carbon tetrachloride, toluene, ethyl ether, and pentane) and if further lowered to 0.6 g/cm, it will dissolve only compounds with parameters of 7-8 (ethyl ether and pentane). 

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