Benzoxazine and polyurethanes were used for the polymer’s synthesis based on the cresol moity having monomer. By adjusting the polyurethane content, three copolymers develop, and each one's corrosion inhibition capabilities are investigated. NMR, FT-IR, and UV-visible spectroscopy techniques were first used to characterise the synthesised monomer, which had cresol as its central component. Then, using the same FT-IR and UV-visible spectroscopy, the produced copolymers are examined. Tafel studies are conducted about corrosion inhibition, and the results suggest that co-polymers with increased polyurethane content have higher anti-corrosive capabilities. In addition, studies of the materials' physical characteristics, such as water absorption and gel content, are conducted. Further, the monomer was subjected to a density functional theory calculation, which examines the improved outcomes that are consistent with another experimental research.