Coating films for corrosion protection of mild steel

The aim of the study was to prepare high performance anti-corrosion formulations for mild steel panels, which are based on mixing solvent-free aliphatic urethane triacrylate oligomer (AUTA) and liquid silicone rubber (LSR) under electron beam irradiation (EB).

Initially, different concentrations of LSR were added to the AUTA-based formulations to prepare 100 μm thin films on different substrates and then exposed to a dose of 10 kGy of EB radiation. The homogeneity and distribution of the previous components were confirmed by FT-IR spectroscopy, water contact angle, and scanning electron microscope. All EB-cured coated films for all formulations were evaluated in terms of gel content, degree of swelling, hardness, bending, glossiness, adhesion, scratching, abrasion, thermal gravimetric analysis, and acid/alkali tests to select the best formulation with high performance properties.

Homogeneous and compatible

The different LSR concentrations were then evaluated as an anti-corrosion agent for mild steel in 3.5 % sodium chloride. The various corrosion-resistant properties of all LSR-containing EB-coated films were evaluated through open-circuit potential measurements, degrees of rust, blistering, adhesion failure at the scribe, water uptake, and weight loss measurements.

The results showed that all the formulations were homogeneous and compatible and their films had high performance properties. It was also found that the formula containing 10 % of LSR per 100 g of coating is considered one of the best formulations, where it gave the highest protection to the mild steel panels without having a negative effect on all the different properties of its films.

The study has been published in Progress in Organic Coatings, Volume 155, June 2021.