Designing of phosphorous based highly functional dendrimeric macromolecular resin as an effective coating material for carbon steel in NaCl: Computational and experimental studies

Abstract

Objective of this study is to develop a highly effective and durable phosphorus based epoxy resin as anticorrosive coating material for carbon steel in 3% NaCl medium. The hexaglycidyl N,N′,N″‐tris (4,4′‐ethylene dianiline) phosphoramide (HGTEDPA) was characterized using spectral methods. The anticorrosive formulation (HGTEDPA‐MDA) was synthesized using HGTEDPA curing with 4,4′‐methylenedianiline (MDA). The formulation (HGTEDPA‐MDA) coated steel specimens were exposed to UV radiation for a specific durable (189 days) and durability of the formulation was tested along with its inhibition effectiveness. The anticorrosive property of the formulation was evaluated using electrochemical (electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP)) methods. Results showed that HGTEDPA‐MDA coating improved the corrosion resistance value even after exposing 180 days to the UV radiation. PDP study suggested that HGTEDPA‐MDA before and after UV radiations acted as mainly anodic and cathodic type of inhibitor, respectively. The EIS and PDP results were corroborated with density functional theory (DFT) and molecular dynamic simulations (MDS) methods and a reasonable good agreement was observed. DFT study revealed that HGTEDPA‐MDA interacts with the metallic surface using donor–acceptor interactions. MDS study revealed that HGTEDPA‐MDA spontaneously interacts with steel surface and adsorb using horizontal orientation.

Experimental and theoretical investigations of new Schiff base compound adsorption on aluminium in 1 M HCl

“…The density functional theory (DFT), MC, and molecular dynamics simulations for this work were performed using Material Studio. The COMPASS forcefield in Material Studio's Forcite module was used to change the geometries of the inhibitor, water, and hydronium ion (H3O + ) [32][33][34][35][36][37].…”

“…A conformer search (Boltzmann jump technique; the number of conformers: 8000; utilizing the COMPASS II forcefield) was undertaken in the early phase of the procedure in order to acquire the lowest feasible starting energy for the molecule while speeding up DFT computations [29][30][31][32][33][34][35][36][37][38][39][40][41][42]. Calculations for DFT were started with the lowest-energy conformer shown by the image in Figure 5.…”

“…Eads / J mol -1 Figure 10. Distribution of adsorption energies of the inhibitor obtained from MC calculations MD is extensively considered a correct representation of the adsorption dynamics [32,33,35,39]. It is evident that after several hundreds of ps of NVT simulation, the inhibitors (Figure 9) adopt a somewhat flat structure on one side of the molecule rings onto the metal surface and is strongly adsorbed onto the Al surface.…”

An Experimental and Theoretical Investigation of the Efficacy of Pantoprazole as a Corrosion Inhibitor for Mild Steel in an Acidic Medium

“…Figure 4 depicts the HOMO and LUMO OM and ESP of the Pantoprazole medication, and Table 3 lists the most often seen DFT indices. The majority of the HOMO and LUMO densities were localized in the region of the molecule that contained the imidazole moiety.When it comes to Pantoprazole, the HOMO and LUMO were significant due to their ability to interact with the Fe (1 1 0) surface via electron donation and acceptation, respectively[2,7,21,[24][25][26][27][29][30][31]36,[43][44][45].…”

“…The majority of the HOMO and LUMO densities were localized in the region of the molecule that contained the imidazole moiety. When it comes to Pantoprazole, the HOMO and LUMO were significant due to their ability to interact with the Fe (1 1 0) surface via electron donation and acceptation, respectively[2,7,21,[24][25][26][27][29][30][31]36,[43][44][45].When the electron affinity and ionization potential of the material were computed, a comparable capacity was obtained. Additionally, the proclivity of the forms of Pantoprazole for adsorption on metal surfaces were enhanced by an appropriate softness value and a relatively low hardness ratio[9,11,46,47].…”