The cardanol formaldehyde resin (CFR) has been synthesized by the condensation of cardanol with formaldehyde (ratio of 1:0.7) in the presence of oxalic acid catalyst. Synthesized CFR was epoxidized using epichlorohydrin (ECH) with 1:10 molar ratio. Cardanol was also directly epoxidized using ECH with the above-mentioned ratio. Synthesized resins have been characterized by Fourier-transform infrared and nuclear magnetic resonance spectroscopic analyses. Thermal properties have been studied by thermogravimetric analysis. Decomposition kinetics have been studied by various kinetic models of the synthesized compounds. In the present study, Horowitz–Metzger, Broido and Coats–Redfern models have been used to calculate the activation energy ( E_a), pre-exponential factor ( A) and rate constant ( K). E_a calculated from all the three models mentioned above was close to each other.

The inhibition effect of unripe fruit peel extract of Musa acuminata (Cultivar variety – Nendran) (MNP) on corrosion of mild steel in 1 N HCl has been investigated by weight loss and electrochemical impedance spectroscopy (EIS) with various concentrations of the extract. The effect of temperature on the corrosion inhibition of mild steel in the temperature range of 30^°C – 80^°C was carried out. The results indicate that MNP extract act as an effective inhibitor in the acid environment and is of mixed type inhibitor having efficiency as high as 96% at 2% inhibitor concentration. The inhibition efficiency of MNP extract increases with the increase of concentration but decreases with the increase in temperature. The inhibitor achieves its inhibition by physical adsorption of nutrients of the peel extract on the surface of the mild steel. The experimental data revealed that the adsorption occurred according to the Langmuir and Temkin adsorption isotherm.