Institute of Chemistry of the Far Eastern Branch of the Russian Academy of Sciences, Vladivostok, Russia

A. S. Gnedenkov, Principal Researcher, Head of the Laboratory, Doctor of Chemical Sciences, Professor of the Russian Academy of Sciences, e-mail: asg17@mail.com
S. L. Sinebryukhov, Deputy Director, Doctor of Chemical Sciences, Associate Professor, Corresponding Member of the Russian Academy of Sciences, e-mail: sls@ich.dvo.ru
V. S. Marchenko, Junior Research Assistant, e-mail: filonina.vs@gmail.com
S. V. Gnedenkov, Director, Doctor of Chemical Sciences, Professor, Corresponding Member of the Russian Academy of Sciences, e-mail: svg21@hotmail.com

A method has been developed for the formation of hybrid inhibitor and polymer-containing coatings on the surface of a bioresorbable magnesiumbased alloy of Mg – Mn – Ce (MA8) system to reduce the material corrosion intensity. A porous ceramic-like coating containing hydroxyapatite was obtained by plasma electrolytic oxidation (PEO). A method for modifying the PEO-layer with a corrosion inhibitor and polymer is proposed. The chemical composition and morphological structure of anticorrosive coatings have been studied by scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS), as well as X-Ray diffraction analysis and X-ray photoelectron spectroscopy. The level of corrosion resistance of samples in saline solution (0.9% NaCl) was determined using electrochemical impedance spectroscopy and potentiodynamic polarization. The rate of samples corrosion with the studied surface layers was determined by volumetric method. Based on the analysis of the results obtained, it was revealed that the samples with a hybrid coating (HC-NC01) have the best resistance to corrosion processes. This type of sample is characterized by a minimum volume of hydrogen released due to corrosion of magnesium (4 times lower than that of a sample with a basic PEO coating). It is shown that samples with a hybrid coating have the lowest value of the corrosion current density, the highest value of the polarization resistance and the impe dance modulus. The mechanism of corrosion in a chloride-containing medium of magnesium alloy samples with coatings impregnated with a corrosion inhibitor has been established. The prospects of using hybrid coatings containing a bioresorbable polymer material and a biocompatible corrosion inhibitor to ensure controlled resorption and increase the bioactivity of magnesium-based implant materials for their subsequent use in medical practice are shown.
Studies of the biocompatible coating formation and the material corrosion rate by volumetric analysis were carried out with the support of RSF (project No. 20-13-00130); studies of the chemical composition and electrochemical properties were supported by RSF (project No. 24-73-10008); X-Ray diffraction analysis data were obtained within the framework of the state assignment of the Ministry of Science and Higher Education of the Russian Federation (project No. FWFN(0205)–2025–0001).

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