Preparation of Anticorrosive Coating with No Solvent for Repairing

The solvent-free fast-curing coating for repairing is prepared using polyurea as matrix and graphite nanoplatelets (GNPs) as fillers. The effects of GNPs on the coating are studied. The coating is prepared by HDI tripolymer and polyetheramine. The GNPs is functionalized (f-GNPs) by aminopro-pyltriethoxysilane (APTES) in mixture of water and ethanol. The performances of the coatings are tested by salt spray time, polarization curves and electrochemical impedance. The coating presents solvent-free and fast-curing characteristics and is suitable for repairing. The f-GNPs provide both physical barrier and coulomb block for the coating. When the f-GNPs added amount is 0.6 wt%, the salt spray resistance time of the coating is more than 420 h, and the corrosion potential is –0.6428 V. The effects of GNPs on coating are investigated. The results can provide a new idea for preparation of anticorrosive coating used for repairing, and can benefit in-depth understanding of the influence of f-GNPs on the coatings. The coating for repairing is prepared by adding f-GNP as fillers. The anticorrosive mechanism and performance of the coating are discussed in detail.