In-vitro degradation behavior of hybrid epoxy-alkyl sol–gel/anodized composite coating on AZ31B Mg alloy

Abstract Mg alloys are considered a promising alternative to use as biodegradable implants. However, the main limitations of these high susceptibility hydrogen evolution and corrosion. Consequently, it is necessary control corrosion rate through surface treatment techniques. In this regard, double layer system, based on first deposition MgO coating subsequent an organo-silane sol-gel (anodized/SGMI) was proposed increase biocompatibility reduce alloy. Sol-gel coatings were prepared using methyltriethoxysilane (MTES), (glycidyloxypropyl) trimethoxysilane (GPTMS), SiO 2 nanoparticles, 1-methyl imidazole (1-MI). 29 Si 13 C NMR measurements performed investigate inorganic-organic network formation during synthesis, characterize structure cured silane coating. According results, addition 1-MI mainly promotes condensation reaction GPTMS MTES. After deposition, higher cross-linking obtained degradation AZ31B alloy in simulated body fluid (SBF) slowed down. The pH over 450 h suggest that anodized/SGMI system may be suitable for short-term implants applications; particularly applications expected degrade after 10-12 days such surgical skin staples. Graphical