On the synergistic corrosion inhibition and polymer healing effects of polyolefin coatings modified with Ce-loaded hydroxyapatite particles applied on steel

Abstract

pH-sensitive hydroxyapatite particles were loaded with cerium ions (Ce-HAP) and incorporated into polyolefin coatings applied on carbon steel. The Ce-modified hydroxyapatite particles were characterized by scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM/EDS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The protective performance of modified and reference polyolefin coatings applied on carbon steel was studied by electrochemical impedance spectroscopy (EIS), and the self-healing capability was evidenced by combining the scanning vibrating electrode technique (SVET) and pH micro-potentiometry with video-imaging, SEM and Raman. The modified coatings showed significantly improved long-term corrosion protection compared to reference coatings. The effect was attributed to the synergistic combination of the corrosion inhibition effect of cerium ions loaded in the HAP particles and polyolefin healing capability.