Izvestiya of Saratov University.
ISSN 1816-9775 (Print)
ISSN 2541-8971 (Online)


Free-radical graft copolymerization acrylamide, 2-sodium 2-acrylamido-2-methylpropane sulfonic onto chitosan

The method presents obtaining hydrosoluble graft copolymer of complicated structure based on сhitosan, acrylamide (AM), sodium 2-acrylamido-2-methylpropane sulfonic (АМPS-Na) in order to obtain fl ocсulant which is resistant to salt of transition metals and heat temperature, and in order to use it as a reagent for oil production processes.

Kinetics of Cold Steel Phosphating

The process of cold phosphating (25°C) of the carbon steel St3 in the zinc nitrate-phosphate system was studied using a set of physical, chemical and electrochemical methods. The electrochemical nature of steel phosphating in the given conditions was confirmed. Ways of improving the phosphating process to obtain corrosion-resistant phosphate coatings on steel were identified: modifying the phosphating solution with an inorganic silicon-containing additive and the subsequent processing of phosphate films in an aqueous solution containing silicon compounds.

Ionic Aggregation of Macromolecules as the Cause of the Kinetic (Non)Stability of Physicochemical Properties of Chitosan Solutions

Hydrodynamic, optical, colloid-flocculating, film-forming and structural morphological properties of diluted chitosan solutions (50–640 kDa) in acetate buffer (0.33 М СН3СООН + 0.2 М СН3СOONa), both initial ones and stored for ~1,850 days, were studied. It has been established that the decrease in the intrinsic viscosity of solutions over time is manifested for the reprecipitated and high-molecular-weight samples of chitosan to a greater degree.