Fedors solubility parameters

The solubility parameter can also be accessed in the form of increments (10). The Fedors solubility parameter of a water-soluble solvent is a value expressed by the square root of cohesive energy of molecules. The Fedors solubility parameter can be calculated as (11) ... 

The Fedors solubility parameters of some solvents are given in Table 2.2. 

There is an online program that can calculate the Fedors solubility parameters from a structural formula drawing input (12). 

Hydrolytically degradable rubbers (i.e., poly( -CL/L-lac), polytrimethylene carbonate (PTMC), and poly(TMC/ -CL)) were synthesized and solution blended with PLA [204]. Due to differences in the Fedors solubility parameters—PLA 22.75 J° /cm PTMC 21.47 J° /cm poly(TMC/ -CL) rubber 21.09 J° /cm , and poly( -CL/L-lac) rubber 21.49 J° /cm —PLA/rubber blends should form immiscible blends, which was confirmed by the presence of two Tg s in the blends. To investigate the effects of matrix crystallinity on impact and tensile strengths, PL As composed of different LLA/DLA ratios (PLLA, PDLLA (95/5), and PDLLA (50/ 50)) were blended with poly( -CL/L-lac) rubbers (0-30 wt %). Poly( -CL/L-lac) rubber had a Tg around —28°C and the relatively long sequence of LLA segments was capable of crystallization. Incorporation of poly( -CL/L-lac) rubber... 

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. 

Fedors, R. F., A Method for Estimating Both the Solubility Parameters and Molar Volumes of Liquids. Poly. Eng. Sci., 1974 14, 147-154. 

Equation 2.41 would be useful if we could estimate the values of the solubility parameters and the partial molal volume of the supercooled liquid solute. Additive procedures, based on functional groups found in the molecule, have been developed to estimate partial molal volumes and solubility parameters (Small, 1951 Hoy, 1970 Konstam and Feairheller, 1970 Fedors, 1974). Another... 

Fedors, R. F. 1974. Amethodfor estimating both the solubility parameter and molarvolumesoflRqiliifdser Eng. Sci.14 147—154. 

While these equations are crude approximations describing the actual behaviors of various polymeric systems, they have widespread experimental viability [123]. These equations assume that the systems are thermodynamically miscible and stable. Equations resolving the solubility parameters of mixtures can also be done using Small s or Fedors methods [124,125]. This latter method only requires the knowledge of the structural formula of the compounds whereas Small s method requires experimental determination of the molar volume. 

Figure 18.12. Predicted solubility parameter (thin line, left-hand y-axis, from the Fedors-like cohesive energy Ecohl) and surface tension (thick line, right-hand y-axis, from generalized molar parachor) of amorphous random copolymers of styrene and oxytrimethylene at room temperature, as functions of the composition.

Ho et al, 1991], The estimated values are shown in Table 12.24, and the three-dimensional representation of the spherical volume of interaction is shown in Figure 12.25. These values were compared with others, calculated using group contribution method [Van Krevelen and Hoftyzer, 1976 Fedors, 1974 Hoy, 1970]. Ho et al. concluded that the calculated values of 8 were in good agreement with the experimental results for PMAN, but appeared to be low for PMAA and MAN/MAA. The methods of predicting solubility parameters of the latter copolymer from known values of homopolymer constituents... 

Note a Calculated by Fedors method b Calculated by Van Krevelen method c Calculated by Hoy method d Calculated from solubility parameter group contribution method. 

Table 2. Estimation of solubility parameters of triclocarban by means of Fedors and van...

Askadskii has shown that Fedors supposition eoneeming the additivity of eontributions of volume of atoms or groups of atoms is not quite eorreet beeause the same atom in an environment of different atoms oeeupies different volume. In addition, atoms ean internet with other atoms in different ways depending on their disposition and this should be taken into aeeount for eomputation of eohesion energy. Therefore, anew seheme of the solubility parameters ealeulation was proposed that takes into aeeount the nature of an environment of eaeh atom in a moleeule and the type of intermoleeular interaetions. This approaeh is similar to that deseribed in the work of Rheineek and Lin. ... 

Askadskii has shown that Fedors assumption that the contributions of atoms or groups of atoms are additive is not quite correct because the same atom in different groups occupies different volume. In addition, atoms can interact with each other in a different way depending on their arrangement within the molecular stracture. These influences were taken into account to increase the precision of the computation of the cohesion energy in a new calculation method for solubility parameters. This takes into a consideration the enviromnent of each atom in a molecule and the type of intermolecular interaction. 

Pirika, Properties estimation Solubility parameter Fedors method, estimation of solubility parameter, java program, Internet, 2013. 

R.E Fedors, A method for estimating both the solubility parameters and molar voliunes of liquids. Polym Eng Sci, 14 (6), 472-472,1974. 

Figurs 4 Plot of solubility, ln(y2). of various copper(It) and chromium(III) fi-di-ketonates in supercritical CO2 at a density of 0.874 g/ml vs. Fedor s solubility parameter of the free ligand. (From Ref. 23.)...

Osmotic pressure Fedors (35) used the osmotic pressure of polymer solutions to determine solubility parameters. 

Group contribution methods These methods have been used to estimate the solubility parameter (17,20,28,33,35, 58,60,61,96,112,121,122). van Krevelen (123), Fedors (35), and Barton (12) have reviewed these techniques and given tables of group values. The molar volume of solvents and polymers can also be estimated by group contribution techniques (1 OS). 

Bicerano (164) and Porter (165) have developed new group contribution techniques for a wide variety of polymer properties. These approaches consider how the different functional groups are connected in the molecule or in the polymeric repeating unit. Bicerano s method uses Fedor s (35) and van Krevelen s (123,163) group contribution values. Both references provide solubility parameter predictions of a number of polymers. 

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