Super-hydrophobic stearic acid layer formed on anodized high purified magnesium for improving corrosion resistance of bioabsorbable implants

Abstract

Magnesium and its alloys are ideal candidates for biodegradable implants. However, they can dissolve too rapidly in the human body for most applications. In this research, high purified magnesium (HP-Mg) was coated with stearic acid in order to slow the corrosion rate of magnesium in simulated body fluid at 37℃. HP-Mg was anodized to form an oxide/hydroxide layer, then it was immersed in a stearic acid solution. Electrochemical impedance spectroscopy and potentiodynamic polarization were used to estimate the corrosion rate of HP-Mg specimens. The results confirm that the hydrophobic coating can temporarily decrease the corrosion rate of HP-Mg by 1000x.

Современные Концепции Изучения Процессов Коррозионной Деградации Материалов И Покрытий: Теория, Практика, Методология Исследований

“…Они были получены путем добавления 10 мл этанольных растворов стеариновой кислоты различной концентрации (0,08; 0,15; 0,3; 0,6 и 1,2 г) в 100 мл водного раствора гидроксипропилметилцеллюлозы. В работе [761] представлен способ формирования гидрофобных слоев на технически чистом магнии путем анодирования и последующего погружения в этанольные растворы стеариновой кислоты различной концентрации (0,05; 0,1 и 0,15 М) с целью обеспечения ингибирования коррозии биорезорбируемых имплантатов. Исследование [769] посвящено повышению износостойкости алюминиевого сплава 1060 при помощи стеариновой кислоты.…”

Experimental Apparent Stern–Geary Coefficients for AZ31B Mg Alloy in Physiological Body Fluids for Accurate Corrosion Rate Determination

“…In this regard, electrochemical impedance spectroscopy (EIS) is ideal for the measurement of corrosion rates changes in Mg alloys obtained from long term in vitro corrosion tests [1,12] due to the nondestructive nature of the technique and its high precision, reliability, and reproducibility. Currently, there are very few studies that report corrosion rate values measured by EIS for Mg alloys in simulated body fluid (SBF) solutions [12][13][14][15][16]. In these studies, the Stern-Geary equation was used for the quantitative estimation of the corrosion current density (i corr ) [13][14][15]:…”

“…Currently, there are very few studies that report corrosion rate values measured by EIS for Mg alloys in simulated body fluid (SBF) solutions [12][13][14][15][16]. In these studies, the Stern-Geary equation was used for the quantitative estimation of the corrosion current density (i corr ) [13][14][15]:…”

Stearic Acid Coated MgO Nanoplate Arrays as Effective Hydrophobic Films for Improving Corrosion Resistance of Mg-Based Metallic Glasses

“…Many existing methods are more costly and complicated [27,28], so it is necessary to develop a new method with lower cost and more convenient operation. In addition, both MgO protection layers and stearic acid layers are reported to effective in improving corrosion resistance of Mg alloys [29][30][31]. The research on the combination of the two protective layers is still lacking.…”