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The swelling of the polymers into solutions represents by itself the complicated process depending on their different properties. That is why the swelling degree can not be determined via any one physical-chemical property of the solvent. The adequate relationship between the swelling degree and the properties of solvents can be obtained only under condition of taking into account the all acting factors by means of the linear multi-parametric equations. [ABSTRACT FROM AUTHOR]

The suggested in publications dependence of the Diels-Alder reaction parameters on the viscosity of the environment is discussed. The preferred description is shown to base on the principle of the linearity of the free energies. In the majority of cases a crucial factor is the capability of solvents of electrophilic solvation. [ABSTRACT FROM AUTHOR]

Data on the distribution of 8-hydroxyquinoline, its methyl-substituted derivatives, and their salts with copper between organic and aqueous phases can be generalized using linear multiparametric equations that take into account the capacity of solvents for specific and nonspecific solvation. [ABSTRACT FROM AUTHOR]

Correlation analysis of the kinetics of thermal decarboxylation of dicarboxylic acids in various media has shown that adequate description requires taking into account the basicity, polarity, and molar volume of the solvent. The rate of the process increases with increase in these parameters, the effect of the basicity of the medium being the determining one, apparently, because of formation of the bond with the carboxylic carbon atom, facilitating the elimination of CO2. [ABSTRACT FROM AUTHOR]

The rate constants for the Beckmann rearrangement of cyclohexanone oxime p-toluenesulfonate in 11 solvents are satisfactorily described by a three-parameter linear correlation including polarizability, electrophilicity, and molar volume of the solvent. The first two factors favor the reaction, whereas increase of the solvent molar volume makes the reaction slower, presumably due to steric hindrances to solvation. [ABSTRACT FROM AUTHOR]

Kinetics of α-alkylacroleins dimerization was studied. It was established that both electronic and steric factors affect the process rate, with the prevalence of the latter factors. [ABSTRACT FROM AUTHOR]

The experimental data on the effect of physicochemical properties of solvent on the rate of hydrogen peroxide decomposition catalyzed by cobalt ions were obtained using a method of adding inhibitors and were generalized quantitatively by the application of multiparametric linear equations. [ABSTRACT FROM AUTHOR]

Electrophilic solvation that operates to weaken the oxygen-oxygen bond is shown to a factor relating to the effect of the media on the decomposition rate of peracid esters. However, an adequate correlation between reaction rate and solvent properties can only be obtained by means of multiparameter linear equations including various characteristics simultaneously. [ABSTRACT FROM AUTHOR]

Solvent effect on the ratio of the endo and exo isomers formed by the Diels-Alder reaction of cyclopentadiene with acrylic acid esters can be described by multiparameter equations involving solvent polarity and electrophilic solvating power as determining parameters. The solvent polarity parameter Ω based on the stereoisomer ratio in the reaction with methyl acrylate cannot be regarded as a universal measure of solvating power, which was demonstrated using a number of examples. [ABSTRACT FROM AUTHOR]

The solubility of organic liquids in water and of water in organic liquids is primarily determined by the capability of organic liquids for hydrogen bonding. Adequate generalization of the solubility data is possible only with multiparameter equations taking also into account other properties of organic components, including the cohesion and molar volume. [ABSTRACT FROM AUTHOR]

The distribution ratios of novocaine and p-aminobenzoic acid between water and 12 organic solvents were correlated with linear multiparameter equations. [ABSTRACT FROM AUTHOR]

The selectivity in the reaction of tert-butyl hypochlorite with 2,3-dimethylbutane in various solvents may be described by a three-parameter correlation equation taking into account the ability of solvents to nonspecific solvation and their cohesion energy density. [ABSTRACT FROM AUTHOR]

The influence of physicochemical properties of solvents on the solubility of radon in them can be described by multiparameter linear equations taking into account various solvent characteristics; the decisive (and negative) effect on the radon solubility is exerted by the cohesion energy density and polarity of the solvent. This approach is efficient for summarizing data on the distribution ratios of radon between organic and aqueous phases. [ABSTRACT FROM AUTHOR]

Specific retention volumes of different organic substances on polyester phases can be generalized by multiparameter equations that take into account the polarity, polarizability, evaporation enthalpy, and molar volume of these substances. The approach allows one to predict the retention volumes of unstudied compounds. [ABSTRACT FROM AUTHOR]

The enthalpies of hydration and solution of organic substances in water at infinite dilution cannot be quantitatively characterized using any single correlation parameter. A correlation analysis using linear multiparameter equations shows that these quantities are governed by the combined effect of the nonspecific and specific solvation and the molar volume. [ABSTRACT FROM AUTHOR]

The rate constants of cycloaddition of cyclopentadiene to unsaturated aldehydes in different solvents cannot be correlated with a single parameter, in particular, the Brownstein parameter. The data set can be fitted only by multiparameter equations in which the decisive factor increasing the reaction rate is the capability of a solvent for electrophilic solvation. The same parameter also governs the ratio of the endo and exo isomers of the addition product. [ABSTRACT FROM AUTHOR]

The dependences of the isomer ratio in photochemical chlorination of 2,3-dimethylbutane and of the selectivity in photochemical bromination of a mixture of cyclopropylbenzene and toluene may be described by linear multiparameter equations. In the first case, the determining factors are the nonspecific solvation power and molar volume of the solvent, and in the second, the molar volume and cohesion energy density. [ABSTRACT FROM AUTHOR]

Correlation analysis of solvent effects on the rate of styrene oxidation showed that the uninhibited process is favored by nonspecific solvation of the substrate and enhanced cohesive energy density of the medium, that both assist the cage effect. The phenol-inhibited oxidation is much contributed by specific solvation as the result of inhibitor-solvent binding. [ABSTRACT FROM AUTHOR]

The enthalpies of vaporization of a series of isomeric compounds containing heteroatoms (ketones, alcohols, halo derivatives) are satisfactorily correlated with the Hammett-Taft equation. [ABSTRACT FROM AUTHOR]

The log rate constants of monomolecular decomposition of azodiisobutyronitrile can be quantitatively correlated with solvent properties by means of linear multiparameter equations including various solvation effects; the key factors are the ability of solvents for electrophilic solvation, which favors decomposition, and cohesive energy density, which unfavors the reaction. [ABSTRACT FROM AUTHOR]

The correlation analysis of data on the equilibrium constants of formation of various charge-transfer complexes ( Ke) in various solvents shows that the solvent polarity alone does not provide sufficiently reliable description of the process. An adequate correlation between Ke and solvent properties can be obtained only with combined consideration of the capability of solvents for specific and nonspecific solvation. [ABSTRACT FROM AUTHOR]

Water-organic distribution constants are determined for oxalic, succinic, and glutaric acids. The constants can be related to the physicochemical characteristics of extractants by linear many-parameter equations that account for the ability of the extractants to specific and nonspecific solvation; therewith, the most important factor is basicity. [ABSTRACT FROM AUTHOR]

There is no linear correlation between the physicochemical characteristics of carboxylic acids, their pKa in particular, and their distribution constants Kd in the diethyl ether-water system; a certain correlation with molar volume Vm was revealed. Better results were obtained with use of multiparameter equations including Vm, polarity, polarizability, and pKa of the acids. For 14 branched and substituted carboxylic acids it was found that their distribution constants between organic and aqueous phases are described by linear multiparameter equations, polarity and basicity of the extractants being the determining factors. The coefficients of the polarity and basicity terms vary in parallel with the corresponding characteristics of the acids. [ABSTRACT FROM AUTHOR]

The solubility of C60 fullerene in organic liquids is not directly related to any of their physicohemical characteristics, but can be quantitatively described by linear multiparameter equations. The solubility increases with increasing solvent polarizability and decreases with increasing solvent polarity and cohesive energy density. Various types of multiparameter equations proposed in the literature were compared to show that they all are suitable but Koppel-Palm's equation is preferred. [ABSTRACT FROM AUTHOR]

The change in the second-order rate constants in the reaction of terephthalyl chloride with ethylene glycol obeys the Michaelis-Menten equation, suggesting that in the first stage a donor-acceptor complex is formed. [ABSTRACT FROM AUTHOR]

Rate constants for dimerization of 2-ethylprop-2-enal in different solvents cannot be approximated using a single solvent parameter. This is possible only with the aid of multiparameter equations. Polar solvents characterized by a high cohesion energy density accelerate the process. [ABSTRACT FROM AUTHOR]

The solvent effect on the rate of reaction of organic reductants with trichloromethylperoxy radicals can be adequaetly described by multiparameter linear equations. The major factor affecting the reaction rate is the solvent cohesion, enhancing the cage effect. [ABSTRACT FROM AUTHOR]

Data on the solubility of 4,4′-isopropylidenediphenol in organic solvents can be quantitatively correlated with a linear three-parameter equation. The parameters exerting a decisive effect on the solubility are the polarity and basicity of solvents, favoring formation of intermolecular hydrogen bonds. At the same time, an increase in the cohesion energy of the medium decreases the solubility of the title compound. [ABSTRACT FROM AUTHOR]

Enthalpies of solution of gallium chloride in organic solvents are controlled by their basicity. The enthalpies of mixing with such a weak electron acceptor as tetracyanoethylene are influenced by both specific and nonspecific solvation. [ABSTRACT FROM AUTHOR]

An initial rate of the isoprene polymerization under the influence of the hydrogen peroxide depends on the properties of solvents. First of all, the electrophylic solvation of the hydrogen peroxide has an influence on the studied process; the non-specific interaction into a system has a lesser impact. [ABSTRACT FROM AUTHOR]

Distribution of natural ramnolipid surfactants between 11 solvents and water was studied. It was found that the dependence between the physicochemical characteristics of extractants and the amount of extracted ramnolipids might be described by polyparametric linear equations. Effect of the basicity of extractant is decisive. [ABSTRACT FROM AUTHOR]

The Mannich reaction of formaldehyde with butyraldehyde and diethylamine in hydrophilic solvents ensuring homogeneity of the medium follows the kinetic relations typical of an irreversible second-order reaction. The rate constants are determined by the ability of solvents to undergo self-association and their electrophilic solvation power; additional inclusion of the solvent polarity via multiparameter Koppel’-Pal’m equation is necessary to obtain a satisfactory quantitative correlation. [ABSTRACT FROM AUTHOR]

The apparent second-order rate constants for the reaction of methacryloyl chloride with methanol regularly increase on raising the acyl chloride-to-alcohol ratio. The variation of the rate constants is described by the Michaelis-Menten equation, indicating that the process involves initial formation of an associate with a probable structure of charge-transfer complex (CTC). Thermodynamic parameters of the CTC formation and rate constants and activation parameters for the transformation of CTC into the products have been determined. [ABSTRACT FROM AUTHOR]