<p class=\"MsoNormal\" style=\"text-align: justify;\"><span class=\"MsoHyperlink\"><strong><span style=\"font-size: 12pt; line-height: 115%; font-family: \'Times New Roman\', serif;\">Two novel Mannich bases were prepared and used as corrosion inhibitors for mild steel in 1M H<sub>2</sub>SO<sub>4</sub>. Their corrosion inhibition behavior were studied by weight loss measurements, potentiodynamic polarization , electrochemical impedance, and SEM with EDX. Electrochemical studies show that the Inhibition Efficiency depends on concentration of the inhibitor and temperature. The inhibitors obey Langmuir adsorption isotherm which indicate the monolayer adsorption of the inhibitor on the mild steel surface. Thermodynamic parameters show that the adsorption of the inhibitor on mild steel surface occurs through electrostatic attraction. Polarization studies reveal that the inhibitors behave as mixed type in 1M H<sub>2</sub>SO<sub>4</sub> affecting both anodic metal dissolution and cathodic hydrogen evolution. SEM and EDX studies show that the formation of surface adsorptive film of the inhibitors on the MS surface.</span></strong></span><strong><span style=\"font-size: 12.0pt; line-height: 115%; font-family: \'Times New Roman\',\'serif\';\"> Addition of halide ions enhanced the efficiency of the Schiff bases through a synergistic mechanism.</span></strong></p>
<p><span class=\"MsoHyperlink\"><strong><span style=\"font-size: 12pt; line-height: 115%; font-family: \'Times New Roman\', serif;\">Key words: Mannich bases, inhibitors, SEM, EDX, Langmuir adsorption isotherm, polarization, impedance</span></strong></span></p>