Corrosion resistance of novel silane-functional polybenzoxazine coating on steel

A novel silane-functional polybenzoxazine (PB-TMOS) coating, with silane groups that can bond to the substrate, was prepared through a dip-coating and thermal curing method. The coating properties were investigated by Fourier transform infrared spectroscopy, solid-state nuclear magnetic resonance spectroscopy, static contact angle measurement, electrochemical and accelerated corrosion tests. The corrosion resistant performance of PB-TMOS coated specimens was considerably enhanced by the high hydrophobicity and water resistance resulted from the dual cross-linking network of polybenzoxazine and Si–O–Si in PB-TMOS matrix.

► Polybenzoxazine coating shows good corrosion resistance for stainless steel.
► The coating is prepared only by thermal cure method without hydrolytic process.
► Dual crosslink network of the coating is studied by FTIR and 29Si NMR spectra.
► Adhesion between coating and substrate is improved by the Fe–O–Si bond.