PROPERTIES OF WATER-SOLUBLE POLYMERS AND THEIR POLYCOMPLEXES IN AQUEOUS SOLUTIONS

Abstract. The interaction of oppositely charged polyelectrolytes (sodium salt of carboxymethylcellulose (NaCMC), methylcellulose (MC), polyethylenimine (PEI) and polydimethyldiallylammonium chloride (PDMDAAС), and unifloc (UF)) in an aqueous environment was studied using the methods of viscometry, spectrophotometry and macroelectrophoresis. It has been established that the interaction of these polyelectrolytes is accompanied by a significant decrease in reduced viscosity (up to 0.1-0.15 dl/g, which is typical for compacted macromolecules of globular proteins), an increase in optical density and an inversion of the sign of the electrokinetic potential. All this indicates the formation of interpolymer complexes from interacting cationic and anionic polyelectrolytes. Experimental results of studying the properties of water soluble polymers and their polyelectrolyte complexes in aqueous solutions at the water/air interface are described and discussed. It has been shown that complex formation in relatively simple systems is accompanied by changes in the pH of the medium, optical, hydrodynamic, electrochemical and other properties of macromolecules. In the systems we studied, the interaction of the system components is not accompanied by variations in the pH of the medium, therefore, information about the interaction of water-soluble polyelectrolytes in the systems we studied was obtained based on viscometric and spectrophotometric titration data, as well as from changes in the electrokinetic potential of macromolecules. The study of the electrokinetic potential showed that the formation of interpolymer complexes in the systems under consideration is accompanied by significant changes in the electrokinetic potential of macromolecules. A study of the properties of mixtures of aqueous solutions of Na-CMC, MC, UF with polydimethyldiallylammonium chloride and polyethylenimine indicates the formation of interpolyelectrolyte complexes that have a more compact structure than the original macromolecules. Key words: polyelectrolytes; flocculation; cross-linking; stability; interpolymer complexes; optical density; polymer.