Spray-On Polymer-Clay Multilayers as a Superior Anticorrosion Metal Pretreatment
Academic Article
Overview
Research
Identity
Additional Document Info
Other
View All
Overview
abstract
2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Pretreatment coatings applied to metals are essential in the overall performance of anticorrosion coating systems. Hexavalent chromium, a widely used pretreatment for aluminum is now considered harmful. Therefore, a need for environment-friendly yet efficient and scalable pretreatment coatings has emerged. Here, the authors present the spray-assisted layer-by-layer (LbL) assembly and anticorrosion performance of a highly ordered polymerclay nanocomposite coating. This approach is an entirely water-based process, allowing for application over large surface areas. This novel pretreatment coating (25 wt% clay) presents a brick-and-mortar multilayered structure, where the montmorillonite clay (MMT) acts as a physical oxygen barrier, while preventing the dissolution of corrosion productsthus delaying corrosion. The branched polyethylenimine polymer (BPEI) mortar provides surface buffering once the corrosion process initiates. The anticorrosion properties of the LbL coating are evaluated using electrochemical measurements and salt-spray testing. This BPEI/MMT system presents good anticorrosion properties, making it a potential alternative pretreatment. (Figure presented.).