Highly durable macromolecular epoxy resin as anticorrosive coating material for carbon steel in 3% NaCl: Computational supported experimental studies

Abstract

The purpose of present study is in the direction of development of an anticorrosive coating formulation of high durability for carbon steel corrosion in 3 wt% NaCl medium. The formulation comprises of a macromolecular epoxy coating (DGEDDS‐MDA) based bisphenol S diglycidyl ether (DGEDDS) cured with a methylene dianiline (MDA). The formulation was characterized by FT‐IR spectroscopy method. Performance of the epoxy coating was represented using PDP and EIS approaches. The formulation acts as effective anticorrosive coating for long durability (180 days). Surfaces of the specimens before and after 180 days exposure to UV radiation were examined using SEM. PDP, SEM, and EIS studies showed that DGEDDS‐MDA acted as highly durable and effective anticorrosive formulation. Results also showed that the formulation acts as interface type inhibitor and its presence enhances the polarization resistance (Rp) value. DFT study suggests that the formulation DGEDDS‐MDA possesses strong ability to interact with metal surface through its several electron rich centers. MD and MC simulations showed that studied formulation effectively adsorb on the substrate (metallic surface). Results of EIS, PDP, and SEM studies (experimental) were well‐supported by DFT, MD, and MC (computational) simulations.

Ab Inito Exploration of Nanocars as Potential Corrosion Inhibitors

“…The RDF of the nitrogen and oxygen atoms (Figure 8) for the NanoCars is under 3.4 Å approving a chemisorption of these molecules on the metal surface. The results from MD and corresponding RDF analysis validate the strong inclination of that these inhibitors adsorb and protect the metal, as they possess exceptional attraction to share/accept electrons with the metal surface [36,37,62]. At the frontier of the formed inhibitor film, a factor that impacts the mobility of corrosive ions (hydronium ion) is the mobility of the inhibitor molecules.…”

“…The previously prominent COMPASSII force forcefield is used for the simulations MC and MD [61] [33,39,40,42,49,62] [63]. The whole 300 ps of the MD trajectory is used for the computation of the Radial Distribution Function (RDF) [42,60,62]. The Fractional free volume (FFV) of the inhibitor films and the occupied volumes of Connolly surface using the following equation [38]:…”

Salen type additives as corrosion mitigator for Ni–W alloys: Detailed electronic/atomic‐scale computational illustration

“…The various parameters such as HOMO, LUMO, ∆ E (HOMO–LUMO), ionization energy ( I ), electron affinity ( A ), dipole moment (Debye), electronegativity ( Χ ), global hardness ( η ), chemical potential ( π ), global softness ( σ ), global electrophilicity ( ω ), electrodonating ( ω −) power, electroaccepting ( ω +) power, net electrophilicity (∆ ω ±) and polarizability (a.u.) with their respective values gained from DFT analysis are shown in Table 1 [26, 28, 31]. From these results, the adsorptions of OPD and PPD, respectively onto the alloy surface are further backed from their relatively soft electron affinities/high ionization potentials, which provides an identical proficiency to swap electrons to the Ni–W alloy surfaces (Table 1) [26, 31].…”

“…The T control was maintained by the Berendsen thermostat. The very often employed Condensed Phase Optimized Molecular Potential II force field was employed for MC and MD calculations [26–31]. The RDF study was performed on the total time scale of the MD trajectory [28, 31].…”

DFT, Monte Carlo and molecular dynamics simulations for the prediction of corrosion inhibition efficiency of novel pyrazolylnucleosides on Cu(111) surface in acidic media

“…Temperature control was achieved via the use of the Berendsen thermostat 19. A frequently employed COMPASSII force field 44 was used for the simulations 39 , 40 , 43 , 45 , 46 . For the computation of the Radial Distribution Function (RDF), the total trajectory was used 43 , 45 , 47 , 48 .…”