Synthesis of Macromolecular Aromatic Epoxy Resins as Anticorrosive Materials: Computational Modeling Reinforced Experimental Studies

Omar Dagdag; Zaki Safi; Yujie Qiang; Hamid Erramli; Lei Guo; Chandrabhan Verma; Eno E Ebenso; Abuzar Kabir; Nuha Wazzan; Ahmed El Harfi

doi:10.1021/acsomega.9b02678

Synthesis of Macromolecular Aromatic Epoxy Resins as Anticorrosive Materials: Computational Modeling Reinforced Experimental Studies

ACS Omega. 2020 Feb 11;5(7):3151-3164. doi: 10.1021/acsomega.9b02678. eCollection 2020 Feb 25.

Authors

Omar Dagdag¹, Zaki Safi², Yujie Qiang³, Hamid Erramli¹, Lei Guo⁴, Chandrabhan Verma^{5

6}, Eno E Ebenso^{5

6}, Abuzar Kabir⁷, Nuha Wazzan⁸, Ahmed El Harfi¹

Affiliations

¹ Laboratory of Agroresources, Polymers and Process Engineering (LAPPE), Department of Chemistry, Faculty of Science and Laboratory of Materials, Electrochemistry and Environment, Department of Chemistry, Faculty of Sciences, Ibn Tofail University, BP 133, 14000 Kenitra, Morocco.
² Chemistry Department, Faculty of Science, Al Azhar University-Gaza, P.O. Box 1277, Gaza, Palestine.
³ Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
⁴ School of Materials and Chemical Engineering, Tongren University, Tongren 554300, China.
⁵ Department of Chemistry, School of Chemical and Physical Sciences, Faculty of Natural and Agricultural Sciences, North-West University, Private Bag X2046, Mmabatho 2735, South Africa.
⁶ Material Science Innovation & Modelling (MaSIM) Research Focus Area, Faculty of Natural and Agricultural Sciences, North-West University, Private Bag X2046, Mmabatho 2735, South Africa.
⁷ Department of Chemistry and Biochemistry, International Forensic Research Institute, Florida International University, Miami, Florida 33199, United States.
⁸ Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 42805, Jeddah 21589, Saudi Arabia.

Abstract

Herein, two bifunctional macromolecular aromatic epoxy resins (ERs), namely, 4,4'-isopropylidenediphenol oxirane (ERH) and 4,4'-isopropylidene tetrabromodiphenol oxirane (ERBr), are synthesized, characterized, and evaluated as anticorrosive materials for carbon steel corrosion in acidic medium. ERs were characterized using proton nuclear magnetic resonance (¹H NMR) and Fourier transform infrared spectroscopy techniques. Investigated ERs acted as effective corrosion inhibitors, and their inhibition effectiveness followed the order ERBr (96.5%) > ERH (95.6%). Potentiodynamic polarization results showed that ERH and ERBr behave as predominantly anodic type and the cathodic type of corrosion inhibitors, respectively. Adsorption of both the studied ERH and ERBr molecules obeyed the Langmuir adsorption isotherm model. Density functional theory and molecular dynamics studies showed that protonated forms of ERH and ERBr contribute more to metal (carbon steel)-inhibitor (ERH/ERBr) interactions than their neutral forms.