Multilayer Coatings Using Epoxy and Superabsorbent Polymer Composite Material with Self Healing Property

The property of superabsorbent polymer (SAP) was investigated as component of composite material for corrosion control application. The composite material is a multilayer coating consisting of SAP particles, epoxy and hardener. The absorption property of SAP at different concentrations of sodium chloride was measured. It included 3% NaCl concentration, which represent the concentration of salt in sea water, an environment which is corrosive to carbon steel. Results showed decreasing absorbency of SAP at increasing concentration of sodium chloride. Predetermined amount of SAP and epoxy were mixed to obtain a homogenous mixture after which the hardener was added and mixed homogenously to form the composite material’s main component. The composite material was studied for absorption properties in an HDPLE substrate and then later applied onto a carbon steel specimen of size 40 mm x 100 cm and thickness of 0.70 mm using paint brush forming a film on the carbon steel surface. After curing, the film was scratched with a definite length using a sharp knife. Immediately, the samples were exposed to cyclic immersion in 3% sodium chloride solution and subsequent drying to run the corrosion test. Results showed that the composite material was able to control corrosion on the surface of the carbon steel which could be attributed to its self-healing property.