A novel functional HPPS/PCL/ZnO composite layer on AZ91 for anticorrosion

• We prepared a functional HPPS/PCL/ZnO layer on AZ91 by dip-coating technique.
• The surface of HPPS/PCL/ZnO sample is with low porosity.
• The HPPS/PCL/ZnO layer can protect magnesium sample efficiently.
• The HPPS/PCL/ZnO layer could release Zinc ion to promote bone formation.

AZ91 magnesium alloy was coated with a novel and functional hyperbranched polyphenylene sulfide/poly(ε-caprolactone)/ZnO composite (HPPS/PCL/ZnO) using dip-coating method in methenyl trichloride containing solution for improved corrosion resistance of the alloy in simulated body fluid (SBF). The surface of the coated sample is with lower porosity and high uniformity. The electrochemical and immersion tests suggested that the corrosion resistance of the sample coated HPPS/PCL/ZnO composite layer coated alloy was higher than that of the PCL coated one. After 20 days׳ immersion in SBF, the HPPS/PCL/ZnO coated composite was still smooth and hardly changed. Therefore, the HPPS/PCL/ZnO composite layer can protect the AZ91 magnesium more efficiently.