Synthesis, characterization and protective efficiency of novel polybenzoxazine precursor as an anticorrosive coating for mild steel

• Published in: Scientific reports Vol. 13; no. 1; p. 5581
• Main Authors: Soliman, Ahmed M. M., Aly, Kamal I., Mohamed, Mohamed Gamal, Amer, Amer A., Belal, Mostafa R., Abdel-Hakim, Mohamed
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 05-04-2023; Nature Publishing Group; Nature Portfolio
• Subjects: 639/166; 639/638; Acids; Bisphenol A; Calorimetry; Coatings; Corrosion; Corrosion resistance; Curing; Differential scanning calorimetry; Efficiency; Electrochemistry; Humanities and Social Sciences; Hydrophobicity; Magnetic resonance spectroscopy; Moisture absorption; Molecular weight; Morphology; multidisciplinary; NMR; Nuclear magnetic resonance; Phenols; Polymerization; Polymers; Scanning electron microscopy; Science; Science (multidisciplinary); Sodium; X-ray diffraction
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-023-30364-x

In this study, 2-[(E)-(hexylimino)methyl] phenol (SA-Hex-SF) was synthesized by adding salicylaldehyde (SA) and n-hexylamine (Hex-NH
2
), which was subsequently reduced by sodium borohydride to produce 2-[(hexylamino)methyl] phenol (SA-Hex-NH). Finally, the SA-Hex-NH reacted with formaldehyde to give a benzoxazine monomer (SA-Hex-BZ). Then, the monomer was thermally polymerized at 210 °C to produce the poly(SA-Hex-BZ). The chemical composition of SA-Hex-BZ was examined using FT-IR,
1
H, and
13
C NMR spectroscopy. Differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and X-ray Diffraction (XRD), respectively, were used to examine the thermal behavior, surface morphology, and crystallinity of the SA-Hex-BZ and its PBZ polymer. Mild steel (MS) was coated by poly(SA-Hex-BZ) which was quickly prepared using spray coating and thermal curing techniques (MS). Finally, the electrochemical tests were used to evaluate the poly(SA-Hex-BZ)-coating on MS as anti-corrosion capabilities. According to this study, the poly(SA-Hex-BZ) coating was hydrophobic, and corrosion efficiency reached 91.7%.