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Polymeric catalysts containing Co3+ were prepared. Their structures and processing characteristics were studied. The kinetics of catalytic oxidation of a dye solution were determined.

The structures and catalytic properties of metal-containing polymers with transition-metal ions and their compositions with metals of different valence were studied. Di- and trivalent Fe and divalent Mn were used to create the catalyst active site.

A method was developed for finding the concentration of fibre-forming polymers in spinning solutions based on extraction and subsequent titrimetric determination of the solvent. It was found that the solvent is totally extracted from the spinning solution in most cases only during titration. When an extractant is added to the solution, two related equilibria are established between polymer and solvent and between solvent and extractant. The acid-base interaction between solvent and titrant shifts the equilibrium toward extraction of the solvent from the polymer solution.

Conditions for measuring an analytical signal on a superuniversal PU-2 polarograph were studied using direct-current, normal-pulse, differential-pulse, alternating-current square-wave, alternating-current sine-wave, and rapid potential sweep voltammetry modes. Dropping-mercury, static dropping-mercury, mercury–graphite, and gold–graphite electrodes were examined with a linear, triangular, and pulse potential sweep. It was demonstrated that the alternating-current square-wave mode, which can be combined with a triangular potential sweep, possesses the best sensitivity.

A method for determining the concentration of polymer in a spinning solution based on potentiometric titration of hydrochloric acid bound by the tertiary nitrogen of the benzimidazole group in the polymer was developed. The method allows reducing the time of analysis by 2–2.5 times in comparison to the dry residue method of analysis. The method was metrologically certified in an active enterprise. The possibility of using the method of linear regression analysis for processing the spinning solution titration curves without plotting them was demonstrated.

The effects of operating modes, alternating-current amplutude, damping, and time delay of the polarograph on the analytical signal were investigated in the pulse mode.

The effect of dye concentrations in solutions on the potential of a copper-selective electrode with a chalcogenide membrane was studied. It was found that the electrode potential depends on the dye concentration in solutions containing no copper ions. Conventional selectivity coefficients of the electrode with respect to dye anions were determined. The selectivity coefficients ambiguously changed with the dye nature and their concentration in solutions. The use of the calibration graph method without taking into account the composition of the test solution gave rise to great errors in the results of determinations.

A procedure has been developed for determining glycerin in impregnation baths containing from 30 to 40% glycerin by wt., and also for determining glycerin in finished fibre containing from 105 to 125% glycerin based on dry fibre.

A rapid method of determining the polymer content of spinning solution in the concentration range from 7–20% by wt. has been developed; it is based on precipitation of the polymer in acetic anhydride, extraction of the solvent, and subsequent titration of it with perchloric acid. A comparison of the results obtained using the rapid procedure and the dry residue method has been carried out. -- The procedure developed is characterized by accuracy and rapidity in the determination.

The spinning solution from the manufacture of fibre from an aromatic polyamide contains dissolved HCl in the free form and HCl bonded to functional groups of the polymer; the freshly spun fibre contains only bonded HCl.

In this article a description is given of an automatic potentiometric method of titrating the acids in DMAA and DMFA and in their mixtures with water. The method was developed by the present writers on T-105 titration apparatus which consists of a titration cell, a pH-340 or pH-673 petentiometer, a magnetic stirrer, an automatic B-701 type buret, a differentiation unit, and an automatic KSP-4 type recording potentiometer.

CONTENTS I. Introduction 244 II. Fundamentals of the theory of non-aqueous solutions 245 III. Solvents used in non-aqueous titrations 248 IV. Titrants 249 V. Methods of titrating basic substances in non-aqueous media 250 VI. Methods of titrating acidic substances in non-aqueous media 252 VII. Practical importance of non-aqueous titrations 256

Modern ideas about acid–base equilibria in amphiprotic solvents (acetonitrile, dimethylformamide, ketones, and others) are discussed. Data are presented for the homoconjugation constants of phenol and benzoic acid derivatives in these solvents and the calculation of acid–base titration curves is described. The question of the solvent acidity scales and their relative positions on a unique acidity scale are discussed. Factors limiting the solvent acidity scale calculated from its autoprotolysis constant are considered. Data are presented for the measured relative (practical) acidity scales for non-aqueous solvents and their mixtures in potentiometric titration. The optimal conditions chosen for acid–base titration are justified. The bibliography includes 180 references.

The review deals with the methods of estimating the differentiating effect of amphiprotic solvents on the acid strengths of phenol and benzoic acid derivatives. New literature data are presented for the dissociation constants and halfneutralisation potentials of electrolytes of the above classes. The possibility of using the Hammett equation to characterise the differentiating effect of solvents is discussed. The available literature values of the autoprotolysis constants of amphiprotic solvents are analysed critically. The problem of the relation between the parameters characterising the differentiating effect of amphiprotic solvents is considered particularly as regards individual groups of electrolytes and the autoprotolysis constant. The causes of the different differentiating capacities of amphiprotic solvents in relation to phenols and benzoic acids are discussed. The bibliography includes 119 references.

CONTENTS I. Introduction 278 II. Theory of the acid–base titration of non-aqueous solutions 279 III. Principles of the acid–base titration of non-aqueous solutions 281 IV. Titration in non-aqueous solutions of bases 284 V. Titration in non-aqueous solutions of acids 285 VI. Titration in non-aqueous solutions of salts 287 VII. Titration of monomeric and polymeric compounds in non-aqueous solutions 288 VIII. Analysis of industrial materials 289

It is possible to determine the dimethylacetamide (DMAc) content in aqueous and aqueous-organic solutions by the potentiometric titration method after completely tying up water with acetic anhydride.

The metrological characteristics of methods of determining chloride ion using the chloride-selective EM-C1-01 electrode, direct potentiometry, or potentiometric titration with AgNO3 or Hg2(NO3)2 solutions have been examined. The methods are characterized by accuracy and reproducibility of results.

The possibility of using the method of direct potentiometry with copper-selective electrodes for determining the copper(II) ion content in process solutions in manufacture of cuprammonium fibres was investigated. The pH region of stable operation of copper-selective electrodes and a method for performing measurements in the entire pH range of the solutions was proposed. The described method can be used for determining the copper(II) ion content in the presence of the components of the process solutions in manufacture of cuprammonium fibres.

Potentiometric, titrimetric, or coulometric methods are applicable for determining the water content of solutions of PVC in DMF or in PFM.