Effect of polyvinylpyrrolidone – polyethylene glycol blends on the corrosion inhibition of aluminium in HCl solution

Abstract

Purpose – The purpose of this paper is to investigate the effect of polyethylene glycol (PEG), polyvinylpyrrolidone (PVP) and blended formulations on the corrosion inhibition of aluminium in HCl solutions at 30-60°C and to study the mechanism of action. Design/methodology/approach – The inhibitive effect of the homopolymers and polymer blend was assessed using weight loss and hydrogen evolution methods at 30 and 60°C. The morphology of the corroding aluminium surface without and with the additives was visualized using atomic force microscopy. The trend of inhibition efficiency with temperature was used to propose the mechanism of inhibition and type of adsorption. Findings – Results obtained show that inhibition efficiency (η%) increases with increase in concentration of the polymers but decreases with increase in temperature. The inhibition efficiency of the homopolymers and their blends decreased with rise in temperature. Inhibition efficiency was found to be synergistically enhanced on blending the two homopolymers with highest inhibition efficiency obtained for (PEG:PVP) blending ratio of 1:3. The phenomenon of physical adsorption is proposed from the trend of inhibition efficiency with temperature. Research limitations/implications – The mechanistic aspect of the corrosion inhibition can be better understood using electrochemical studies such as potentiodynamic polarization and electrochemical impedance spectroscopy. Originality/value – Studies involving the use of polymer blends/mixtures as corrosion inhibitor for metals in corrosive environments are scarce. The results suggest that the mixture could find practical application in corrosion control in aqueous acidic environment. The data obtained would form part of database on the use of polymer–polymer mixtures to control acid-induced corrosion of metal.

Synergistic effect of polyethylene glycols and rare earth Ce4+ on the corrosion inhibition of carbon steel in sulfuric acid solution: electrochemical, computational, and surface morphology studies

“…In literature studies, synergism between organic inhibitors and halide ions against corrosion of metal in acidic solution has been investigated [15][16][17][18]. The synergistic inhibition effect of combinations of two polymers has been presented in literature; For instance, Umoren [19] and Umoren et al [20] reported a synergistic effect of polyethylene glycol-polyvinyl pyrrolidone blends for inhibition of corrosion of mild steel and aluminum in acidic solution. The results suggested that the mixture could find practical applications for corrosion control in acidic aqueous environments.…”

In-situ preparation, characterization and anticorrosion property of polypropylene glycol/silver nanoparticles composite for mild steel corrosion in acid solution

“…DS * values are all negative which implies that the activated complex in the rate-determining step represents an association rather than dissolution, meaning that a decrease in degree of disorderliness of the system takes place on moving from reactants to activated complex [7,53]. The positive sign of DH * reflects the endothermic nature of mild steel corrosion in 0.5 M H 2 SO 4 solution [54].…”

“…Inorganic (particularly chromates, dichromates, nitrites, nitrates, phosphates, etc.) and organic (mostly those with O, N, S, and P atoms and/or p electrons) compounds have been effective in this regard [5][6][7] but the toxic nature of most inorganic compounds to the natural ecosystem and the exorbitant prices in addition to the tedious synthetic route of organic compounds have been very worrisome. Polymers, both naturally occurring and synthetic had been tested for metal corrosion inhibition ability [8,9] so as to serve as replacement for the inorganic and organic corrosion inhibitors.…”

Organic corrosion inhibitors for aluminium and its alloys in acid solutions: a review

“…Umoren et al 106 tested polyethylene glycol (PEG) and PVP as well as their mixtures as corrosion inhibitors for 3SR (98.60% aluminium) aluminium alloy in 0.1 M HCl solution at 30-60 °C, using the WL and HE techniques. The inhibition effectiveness of the single compounds increased with increasing compound concentration, but decreased with increasing temperature.…”