No abstract

Benzoxazine monomer prepared from vanillin and n-butylamine was characterized by 1H NMR, 13C NMR, FT-IR and UV visible spectroscopic techniques. The synthesized monomer was coated on the mild steel with isocyanate hardener in varying concentrations of isocyanate of the poly(VaBz-PU) and cured. The thermal properties of the monomer with and without isocyanate hardener were studied by TGA and DSC methods. The effect of various concentrations of isocyanate (PU) hardener with benzoxazine monomer on hardness, water absorption and gel absorption was investigated. Various concentrations of PU hardener with benzoxazine coating (VaBz-PU) on the mild steel were investigated by the electrochemical impedance and polarization studies. The study revealed that an increasing concentration of isocyante in the coating with benzoxazine increased their thermal, chemical and anticorrosive properties. The DFT calculations were also performed to support the anti-corrosive ability of the material.

10-(2-hydroxyphenyl)-hexahydro acridinediones were treated with chloroacetyl choloride to give 10-(2-chloroacetyloxyphenyl) hexahydro acridinediones, which were treated with NaN3 in acetone followed by reaction with DMAD yielded 10-[2-(1-triazolo-4,5-dicarboxymethyl)acetyloxyphenyl]-3,4,6,7,9,10-hexahydro-1,8-(2H,5H)-  acridinediones.

In this study, the durability of polyurethane adhesives are successfully developed using silane-functionalized polybenzoxazine@CeO2 nanocomposites. The electrochemical measurements were used to investigate the mechanical strength of polybenzoxazine nanocomposite with polyurethane materials. The superior results in the process of passivation film that also controlled the dissolution of metal have been characterized by UV-visible, XRD, SEM/EDX, FT IR, TGA-DTA-DSC, micro hardness, gel absorption and water absorption analyses. The mechanical performance of the coated surface that supported up the electrochemical investigations was enhanced by the incorporation of silane functionalized polybenzoxazine@CeO2 nanocomposites with polyurethane. The use of ployurthane in the TGA process increases the cross-linked density of the coating, resulting in high thermal stability. As a result of their superior anticorrosive property, the proposed polybenzoxazine@CeO2 nanocomposites with polyurethane films offer the openings for the development of unique, state-of-the-art anticorrosive adhesives across a wide range of sectors.

Corrosion is a significant issue with metallic materials, notably in steel due to its extensive use in a variety of industries. Benzoxazine polymers have been used to produce anti-corrosive compounds that have a remarkable ability to limit corrosion. In the same ink line, we have explored a new approach with a very hydrophobic benzoxazine monomer which is co-polymerized with urethane, and its characterization was studied with IR, UV, and NMR techniques. The corrosion resistance of the same is investigated using Tafel polarization and EIS experiment methodologies. The DFT and MEP studies explain the reactivity towards the anti-corrosive properties of the monomer.