Investigation of a hydrophobically associating AMAHS polyacrylamides: A new corrosion inhibitor for mild steel in HCl

Abstract

A polyacrylamide with capsaicin‐derived monomers (AM–MAA–AMPS–HMBA–SMA; AMAHS) was synthesized and investigated as a novel environment‐friendly polymer inhibitor for Q235 mild steel at 25°C in 1 M HCl solution. The inhibition efficiency was evaluated by weight loss measurements, electrochemical experiments, and surface investigation methods as well as by theoretical calculations. Experimental results indicated that the efficiency of AMAHS was up to 94.86% at the concentration of 2 g/L. Electrochemical tests and surface morphology analysis showed that AMAHS served as a mixed‐type corrosion inhibitor, which could be adsorbed and self‐assembled on the surface of mild steel forming a highly hydrophobic protective film (contact angle of 172°). Density functional theory calculations revealed that heteroatoms in AMAHS, such as O, N, S, are active sites in forming coordination bonds with surface iron atoms. In addition, hydrophobic groups played an important role in protecting the metal surfaces from corrosion media.

Investigating the potential of casein as a sustainable material in inhibiting the corrosion of aluminum in hydrochloric acid

“…[ 25 ] Assuming that the AA1060 samples immersed in the blank or the casein‐amended HCl solutions were uniformly corroded, the corrosion rate (CR; in g m −2 h −1 ) of the specimens was calculated using Equation (): $$$\text{Corrosion rate}\,(\text{CR})=(\unicode{x02206}W)/(A\times t),$$$where Δ W represents the decrease in the weight of the aluminum coupons (in grams; g ) with the total surface area (in m 2 ; A ) that occurred over a particular time interval (in hours; t ). [ 26 ]…”

“…In another research, guar gum was similarly considered as a mixed‐type corrosion inhibitor where it was used to inhibit the corrosion of aluminum in 1 M HCl. [ 26 ]…”

“…In another research, guar gum was similarly considered as a mixed-type corrosion inhibitor where it was used to inhibit the corrosion of aluminum in 1 M HCl. [26] The changes in the polarization resistance (R p ) of the metallic coupons also reveal the effectiveness of an inhibitor. It is noticeable that in the absence of casein, R p was about 0.632 kΩ cm 2 which increased to 4.102 kΩ cm 2 when 500 ppm casein was present in the electrolyte.…”

Synthesis of Hydrophobically Associating Polymers with Natural Product Structures by a One‐Pot Method – Comparison of Ethanol Treatment and Freeze‐Drying

“…In previous research, our group designed and synthesized various natural product compounds, including N‐(2‐hydroxy‐3‐methylacrylamido‐4,5‐dimethylbenzyl)acrylamide (HMMAM) using Friedel‐Crafts alkylation reaction [21–25] . These capsaicin derivative monomers are cost‐effective, easy to prepare in large quantities and are nonpolluting to the environment.…”

“…[22] In previous research, our group designed and synthesized various natural product compounds, including N-(2-hydroxy-3methylacrylamido-4,5-dimethylbenzyl)acrylamide (HMMAM) using Friedel-Crafts alkylation reaction. [21][22][23][24][25] These capsaicin derivative monomers are cost-effective, easy to prepare in large quantities and are nonpolluting to the environment. They have a stable structure, their high chemical reactivity can produce supramolecular interactions with other monomer groups, and they can make the polymer produce certain cross-linking.…”