Microstructure and anti-corrosion properties of acrylic bone cement-based with MOF nanostructured hybrid coatings on AZ31 Mg alloy

Abstract

Surface modification of biomedical AZ31 magnesium (Mg) alloy substrates with biocompatible and applicable polymer coatings is an effective and simple method to improve corrosion resistance. Herein, the biodegradable acrylic bone cement incorporation with different content of metal organic frameworks (Ce-MOFs or Zn-MOFs) coated on biodegradable Mg alloy (AZ31) substrates was fabricated by using a dip-coating method. Then, various characterizations like X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) and the water contact angle (WCA) tests were performed to determine the composition, morphology, structure, and wettability of the coatings. The compact acrylic bone cement coatings improve the hydrophilic effect due to the micro/nanostructure of acrylic and hydrophilic groups, but the addition of a small amount of Ce-MOF and Zn-MOFs structures reduces the hydrophilic effect of the coating surface. According to the electro-chemical analysis, prepared acrylic coating has better corrosion behavior compared to AZ31 sample. The PM sample demonstrates the lowest corrosion current density (icorr = 0.095 mA cm−2) compared to other samples. The dense acrylic compact coatings with higher amount of Ce-MOF content blocks the pores in the coating and lead to an inhibitory effect and improved the corrosion behaviors. The dense acrylic bone cement containing MOF coatings with improved electrochemical activity inhibits diffusion of the aggressive ions to the alloy surface.