Phosphorous-based epoxy resin composition as an effective anticorrosive coating for steel

Abstract

Epoxy resin (ER) is an attractive material for metal protection against corrosion; it can form a strongly adhered film onto a metal surface through its multi coordination sites. In this study, an epoxy resin-based formulation was designed, prepared, and applied onto steel surface with and without a pigment. The anticorrosive formulation (ER-MDA-ZP) was prepared from the ER and the hardener 4,4′-methylene dianiline (MDA) in the presence of the anticorrosive pigment zinc phosphate (ZP). A second standard formulation (ER-MDA) was prepared without ZP. The epoxy and the hardener react to form a 3D cross-linked polymeric network with multicoordination sites (hydroxyl and amino groups) for metals. The characterization of the epoxy resin was performed using Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance ( 1 H and 31 P NMR). Both samples exhibited excellent thermal properties as they subjected to thermal analysis using differential scanning calorimetry. The ER-MDA-ZP formulation showed a higher glass transition temperature (T g ) than ER-MDA. The coated steel specimens were immersed for 1 h in a 3 wt% NaCl solution and their anticorrosive properties were monitored by electrochemical impedance spectroscopy (EIS). The total resistance (R t ) values obtained by the EIS method for the ER-MDA and ER-MDA-ZP formulations were 21,383 Ω cm 2 and 55,143 Ω cm 2 , respectively. The coated steel samples after the acid treatment were subjected to aging by exposing them to a UV light for 2000 h. The aging caused the R t values to drop to 1621 Ω cm 2 and 7264 Ω cm 2 , respectively. The results indicate the formation of a highly stable film of ER-MDA-ZP formulation on the steel surface that withstands an accelerated corrosive environment of 2000 h exposure to UV light and 1 h of immersion in a 3 wt% NaCl.

Rheological, electrochemical, surface, DFT and molecular dynamics simulation studies on the anticorrosive properties of new epoxy monomer compound for steel in 1 M HCl solution

“…1 by reacting 1,2-aminobenzamide (I) with epichlorohydrin (II) in the presence of triethylamine, according to a procedure reported in the literature. [7][8][9] 2.1.1. Synthesis of tetraglycidyl-1,2-aminobenzamide (ER).…”

“…The synthetic procedures and characterization of these epoxy monomers have been discussed in detail in the literature. [7][8][9] The epoxy monomers are widely used because of their excellent adhesion performance. 10 In our laboratory, we have successfully synthesized some aromatic epoxy monomers, employing reagents containing at least two mobile hydrogens of diamine type and alcohols (mostly with low molecular weights) to react with epichlorohydrin.…”

DGEBA‐polyaminoamide as effective anti‐corrosive material for 15CDV6 steel in NaCl medium: Computational and experimental studies

“…Epoxy resins are one of the most significant, attractive, and effective materials for anti‐corrosive coatings of steel and other alloys because of their high durability and high effectiveness that resulted due to the presence of numerous adsorption centers …”

“…The epoxy resins can be converted into thermosetting materials by mixing them with some curing agents during their application on the surface of metals and alloys. The association of high crosslinking and good adhesion property of the epoxy resins and materials derived make them ideal and highly effective as anticorrosive agents . Unlike to the traditional coating, epoxy resins‐based coating are muscularly impervious to most of the chemicals and constituents of the surrounding environment.…”

Dual Component Polymeric Epoxy-Polyaminoamide Based Zinc Phosphate Anticorrosive Formulation for 15CDV6 Steel

“…Among organic coatings, water-based epoxy coatings are the most attractive due to their unique mechanical properties, superior adhesion to substrate, good thermal stability, excellent corrosion resistance and chemical resistance. In addition, they can be available at a low cost [10,11] and are nontoxic. These attractive properties could be attributed to high the cross-linking density and to the functional groups such as amines and hydroxyl present in the polymer coating [12].…”