Optimizing maleic anhydride microcapsules size for use in self‐healing epoxy‐based coatings for corrosion protection of aluminum alloy

Abstract

Due to the significance of self‐healing coatings in recent years, there has been increasing desire to optimize process parameters for effective control of functions of the coatings for durable application. Among various approaches for achieving desired optimized properties, the use of central composite design (CCD) of the response surface methodology (RSM) remains an effective and reliable technique. Thus, the objective of this study was to develop an appropriate model for optimization of size of microcapsule to be used in synthesis of maleic anhydride‐based microcapsules for self‐healing function in defective epoxy coating. In this regard, a model was generated to estimate the effect of two process parameters (stirring speed and reaction time at constant temperature). The average size of microcapsules obtained experimentally (24.46 μm) was closely comparable to 25.27 μm obtained by the theoretical technique. Microcapsules were prepared based on these optimized size of microcapsule and the synthesized microcapsules were characterized. Also, effectiveness of these microcapsules in coatings was characterized by studying their adhesion performance, self‐healing functions under salt spray corrosion test, and anti‐corrosion by use of electrochemical impedance spectroscopy (EIS). Successful self‐healing function has been demonstrated by reason of anti‐corrosion effectiveness of maleic anhydride‐filled microcapsules.

Polyester-Based Coatings with a Metal Organic Framework: An Experimental Study for Corrosion Protection

“…As a disadvantage, the protection offered by organic layers is expensive, requiring constant replacement of the surfaces by painting; therefore, better alternatives are needed [1]. The type of organic compound used, the compactness and adhesion of the deposited layer dictate the quality of the protective layer and, as a result, its anti-corrosion protection [2][3][4]. Most organic coating systems include polymers (epoxies, acrylics, polyurethanes, etc.…”

“…In recent years, the use of intelligent coatings capable of acting over time (self-healing and corrosion resistance) has been studied. Microcapsules using the double emulsion technique with similar action have been prepared [3,4]. The majority of intelligent coatings offer limited protection (the adherence of the newly formed film is crucial).…”

A General Strategy towards Superhydrophobic Self-Cleaning and Anti-Corrosion Metallic Surfaces: An Example with Aluminum Alloy

“…However, it was found that the additive of organotin is extremely toxic, which was forbidden in the EU in 2003 and globally in 2008 [8]. In recent years, the coatings based on organics [9,10] have been developed as alternatives, such as the epoxy coatings [11][12][13]. However, 90% epoxy coatings were achieved using diglycidyl ether of bisphenol A, deriving from bisphenol A. Bisphenol A has been proven to be harmful to the endocrine system and may cause feminization [14].…”

Effect of relative humidity on corrosion of Q235 carbon steel under thin electrolyte layer in simulated marine atmosphere

“…Kok-Hui Goh evaluates the effects of dosage, pH and contact time on high-dose phosphate inhibition for copper corrosion control and their interactive effects by RSM (Goh et al, 2008). Njoku uses RSM to optimize maleic anhydride microcapsules size for corrosion protection of aluminum alloy (Njoku1 et al, 2018).…”