Rublova Y. Polyhexamethyleneguanidine derivatives as complex inhibitors of electrochemical and related processes on mild steel in a neutral medium

The subject of investigation: interphase and electrochemical processes in neutral media with ionic polyelectrolytes and their complexes. Purpose of investigation: the establishment of patterns of influence of modified polyhexamethyleneguanidine (PG) and their complexes on the electrochemical corrosion processes, phase formation and biofouling which occurs on the steel surface in neutral media, and the development of new effective inhibitor with complex action. Metods of investigation: gravimetry and voltammetry methods, kulonostatic method, the method of Wilhelmi; titrimetric method, disk-diffusion method, X-ray analysis, scanning electron microscopy, UV, IR spectroscopy. Theoretical and practical results: the new data on the impact of the modification PG on their adsorption behavior and the electrochemical processes on steel, as well as processes of scaling and biofouling. A highly complex composition of action, which can be used in water recycling systems was proposed. The novelty of the provisions and the results: for the first time carried out a series of studies of the structure and physicochemical properties of the modified derivatives of PG that allowed to establish the regularities of modified PG adsorption and show that grafting of carboxyl and phosphonate groups, as well as the formation of metal complexes leads to the growth of its adsorption capacity on different phase boundary; found that PG derivatives are able to prevent scale deposition by binding calcium and magnesium ions in the form of soluble complex and adsorption to precipitate crystals; to show that the biocidal properties of PG enhanced by grafting to it carboxyl and phosphonic groups and the formation of zinc complexes. Scope of use: the proposed inhibitor can significantly reduce corrosion, scaling and biofouling in heat power engineering, metallurgy, oil and gas production and processing industry.