Epoxy pre-polymers as new and effective materials for corrosion inhibition of carbon steel in acidic medium: Computational and experimental studies

Abstract

Present study is designed for the synthesis, characterization and corrosion inhibition behavior of two diamine aromatic epoxy pre-polymers (DAEPs) namely, N 1 ,N 1 ,N 2 ,N 2 -tetrakis (oxiran-2-ylmethyl) benzene-1,2-diamine (DAEP1) and 4-methyl-N 1 ,N 1 ,N 2 ,N 2 -tetrakis (oxiran-2-ylmethyl) benzene-1,2-diamine (DAEP2) for carbon steel corrosion in acidic medium. Synthesized DAEPs were characterized using spectral (Nuclear magnetic resonance ( 1 H NMR) and Fourier transform infrared-attenuated total reflection (FTIR-ATR)) techniques. Viscosity studies carried out at four different temperatures (20–80 °C) increase in temperature causes significant reduction in their viscosities. The anticorrosive properties of DAEPs differing in the nature of substituents, for carbon steel corrosion in 1 M HCl solution was evaluated using several experimental and computational techniques. Both experimental and computational studies showed that inhibitor (DAEP2) that contains electron releasing methyl (-CH 3 ) showed higher protectiveness as compared to the inhibitor (DAEP1) without substituent (-H). Electrochemical results demonstrate that DAEPs act as reasonably good inhibitors for carbon steel in 1 M HCl medium and their effectiveness followed the sequence: DAEP2 (92.9%) > DAEP1 (91.7%). The PDP results show that the diamine aromatic epoxy pre-polymers molecules (DAEPs) act as mixed type inhibitors. Electrochemical study was also supported using scanning electron microscopy (SEM) method were significant improvement in the surface morphology of inhibited (by DAEPs) metallic specimens was obtained. Results derived from computational density functional theory (DFT) and molecular dynamics (MD) simulationsand studies were consistent with the experimental results derived from SEM, EIS and PDP electrochemical studies. Adsorption of the DAEPs obeyed the Langmuir adsorption isotherm model.

Development rheological and anti-corrosion property of epoxy polymer and its composite

“…Recently, the research developed in the field of epoxy polymer aims to replace bisphenol A with a precursor without degrading the physical and chemical properties [23, 24]. In this paper, we presented the synthesis of a new epoxy polymer from a reagent containing four mobile hydrogen atoms such as methylene dianiline (MDA) with phosphorus pentachloride (PCl 5 ) [25].…”

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

“…Electrochemical measurements performed on carbon steel with and without the epoxy coating in 3 wt% NaCl solution previous to and subsequent to 180 days of UV exposure using Potentiostat PS 200 device as described in our previous studies . The device is connected by means of a three‐electrode arrangement consisting of pure Pt as the auxiliary or assisting electrode (CE), saturated calomel the same as the reference electrode (SCE) and carbon steel panels the same as the working electrode (WE).…”

“…Prior to starting the electrochemical experiments, the WE permitted to corrode liberally for the macromolecular epoxy coating before and after 180 days of UV exposure for 1,800 s in order to acquire the establishment of OCP (open circuit potential). Instrumentation employed in present study for EIS and PDP studies was identical as reported previously …”

Rheological properties of composite polymers and hybrid nanocomposites

“…The results showed that all mixtures of 0%, 5%, 10% and 15% HGCP behave like a solid, with the rheological behavior (G 0 and G 00 ) almost independent of angular velocity. The occurrence of G 0 and G 00 has been determined by several authors [28,29,30].…”