Water and corrosion resistance of epoxy-acrylic-amine waterborne coatings: Effects of resin molecular weight, polar group and hydrophobic segment

A two-step esterification process is developed for the synthesis of epoxy-acrylic-grafted-copolymer waterborne resins. The effect of synthesis parameters on water and corrosion resistance of the waterborne coatings is investigated. The results reveal that moderate increasing of the resin molecular weight (<8000 Da) and carboxyl content (<27 wt.%) increased the crosslinking property, thereby improved the anticorrosion performance of the coatings. Longer epoxy-octanoic hydrophobic chains can provide stronger shielding effect on the hydrophilic portion of the polymer matrixes. The polar group content in a waterborne resin can be optimized for better anticorrosion performance, whereas the optimal value is coating-specific. (c) 2013 Elsevier Ltd. All rights reserved.