Facile Fabrication of Nanoclay Reinforced Waterborne Organic Coatings for Corrosion Protection

The reinforcement effect of nanoclay on the corrosion protection properties of waterborne thin organic coatings was studied. The coating matrix was a commercial formulation for galvalume steel substrates. Two kinds of clays (laponite RDS and optigel WH) were employed as the barrier reinforcement in the composite coatings. Both kinds of the clays were exfoliated into monolayers of silicate with disordered structures at a filler content of 2 wt.%. Facile exfoliation and effective dispersion of clay was achieved with the assistance of a titanate coupling agent. The corrosion protection properties of the composite coatings were significantly improved with the addition of 3 wt.% laponite RDS or 2 wt.% optigel WH. The addition of an excessive amount of clay decreased the anticorrosion properties of the composite coatings. The fabrication methods of nanoclay-reinforced thin organic coatings involved only physical blending and latex mixing at ambient temperature, which can be easily scaled-up for mass production.