Fabrication of Smart Micro/Nano Self-healing Coatings on the Basis of Urea-formaldehyde Capsules Containing Tong Oil and Optimizing them for Corrosion Inhibition

In this study، a set of smart coatings on the basis of micro/nano capsules، with the aim of corrosion reduction in oil and gas pipelines، has been investigated. The shell of capsules was made of urea-formaldehyde and their core was tong oil، which acts as a healing agent. In the present work، some parameters affecting the performance of the coating such as mechanical agitation rate in the encapsulation process، capsule size، and dispersed capsule concentration were varied and optimized. In addition، other coating properties such as adhesion and corrosion resistance of the coating were investigated by adhesion pull-off tests and electrochemical impedance spectroscopy respectively. The results indicated that using finer capsules، which were created at higher stirring rates، improved the corrosion resistance and adhesion to the substrate. Moreover، with the incorporation of capsules in the matrix، the protective ability was significantly increased; this could be realized from the results of water absorption and electrochemical tests. A capsule concentration of 15 wt. % was the optimum value which led to the highest corrosion resistance of the coating.