M. I. Vinnik

Kinetics and mechanism of the hydration of the equilibrium mixture of 3-methyl-1-buten-3-ol and 3-methyl-2-buten-1-ol with isoprene in aqueous solutions of sulfuric acid

The kinetic relationships of the hydration of an equilibrium mixture of 3-methyl-1-buten-3-ol (dimethylvinylcarbinol, DMVC) and 3-methyl-2-buten-1-ol (dimethylallyl alcohol, DMAA) with isoprene (C5H8) were investigated in aqueous solutions of sulfuric acid from 24.9 to 49.7% at 25°C. Data were obtained on the mechanism of hydration of the equilibrium mixture of DMVC and DMAA with isoprene.

Acidity function scale for H2SO4 solutions in phenol-acetone solvents with low water content at 25°C

The indicator method was employed to measure the acidity function H0S of H2SO4 solutions in solvents consisting of an equimolar mixture of phenol and acetone with 0.8% water (from 3.6·10−4 to 2.6·10−2 M H2SO4) and 2.5% water (from 4.3·10−4 to 0.32 M H2SO4) and of phenol and acetone in a molar ratio of 1:1.5 with 0.67% water (from 1.63·10−4 to 7.77·10−2 M H2SO4) and 2.09% water (from 4.49·10−4 to 0.35 M H2SO4) at 25°C. The indicators employed were 4- and 2-nitroaniline.

Acidity function of HCl solutions in mixtures of H2O with γ-butyrolactam

Conclusions1.The values of log (CB/CBH+) of 4-, 2-, and 2,6-dichloro-4-nitroanilines in the H2O-HCl-γ-butyrolactam (BL) system were obtained at 25°C, at various BL and HCl concentrations under conditions wherein BL is either nonionized, partially or completely ionized.2.It was shown that if BL is either completely nonionized or completely ionized, the Ho of an aqueous solution and the HoS of a solution of HCl in a H2O-BL mixture are equal at the same H5O2+ concentrations on a molar ratio scale.

CALORIMETRIC STUDY OF SUPRAMOLECULAR STRUCTURE FORMATION IN THE COURSE OF LINEAR EPOXIDE-AMINE POLYCONDENSATION. EPOXY-AMINE CATENATE POLYMERS

The formation of linear epoxy-amine polymers has been studied using the calorimetry method. Catenate polymer (“olympic gel”) is produced in the course of linear polycondensation of aniline with resorcinol diglycidyl ether. A relation was found to exist between the kinetics of the processes and the glassy state transition temperatures for the samples obtained in the reaction. A model of glassy state formation is proposed, In accordance with latter the polymeric glasses are considered to have the dissipative structure resulting from a kinetically controlled phase transition.

Hammett acidity function of water-salt solutions of strong acids

The values of the acidity function H0s of HCl-KCl-H2O solutions (mKCl=2.73, 3.61) at 25°C were determined by the indicator method. An infinitely dilute solution of the acid in a H2O-KCl mixture of fixed composition is the standard state for H0s. A method for calculation of H0s of water-salt solutions of strong mineral acids was proposed.

Acidity functions H0 of aqueous and aqueous-ethanol solutions of HCl at 50°C

Conclusions1.The acidity function H0 of aqueous solutions of HCl (up to 9.33%) at 50°C was measured by the indicator method (indicators-4- and 2-nitroanilines). It was shown that the H0 of these solutions at 25 and 50°C are equal for the same HCl content in the solution.2.The ionization of 4-nitroaniline was studied in aqueous-ethanol solutions of HCl at 16.35; 25.32; 54.27% EtOH at 50°C. It was found that as at 25°C, the acidity functions of the aqueous and aqueous-ethanol solutions of HCl are equal at the same concentration of the acid, expressed on molar ratios scale m. A standard state for each composition of the solvent is an infinitely dilute solution of an acid in this solvent.

Effect of water on the ionic-molecular interaction in the acetone-phenol-H2SO4 system

Complexation in the acetone-phenol system and the effect of water on the ionic-molecular interaction in the acetone-phenol-H2SO4 system at 30‡C were investigated by MFTIR (multifrustrated total internal reflection) IR spectroscopy. Acetone and phenol form a 1∶1 complex (PAC-l). In an excess of acetone, all of the phenol is bound with this complex, and a 2∶1 complex (PAC-2) is formed in an excess of phenol. Relatively small amounts of H2O virtually do not decompose PAC-1. A broad continuous absorption band due to the formation of complexes with a strong quasisymmetric H bond is observed in the IR spectra of solutions with H2SO4. Quasi-ion pairs HOSO2O...H...OC-(CH3)2, are formed in an anhydrous system. The acid-solvent complexes decompose and (H2O...H...OH2)+ ions are formed on addition of water. The continuous absorption coefficients, ε2000, of (H2O...H...OH2)+ ions and quasi-ion pairs were determined.

Protonating power of aqueous and aqueous-alcoholic solutions of HC1 in the presence of inorganic salts

AbstractThe indicator method has been used to obtain a scale of protonating power of the medium Hos for solutions of HCl in the solvents of constant composition H2O-EtOH-KCl and H2O-NH4Cl at 25‡C. It is shown that in the solvents investigated the value of HOs in HCl is the same as H0 in aqueous solution for the same ratios of the concentrations of HCl and of the basic solvents H2O and EtOH. A method is worked out for estimating the value of

Method for determining the thermodynamic activity of HClO4 in water-alcohol solvents

pK_{BH^{ + ^s } }