ABSTRACT
The binder and the pigment are the most important elements; they may be said to perform the corrosion protection work in the cured paint. Anticorrosion pigments are chemically active in the cured coating, whereas pigments in barrier coatings must be inert. The binders used in anticorrosion paints are almost exclusively organic polymers. Hybrids, or combinations of different polymer families, are also used. Examples of hybrids include acrylic– alkyd hybrid waterborne paints and the epoxy-modified alkyds known as epoxy ester paints. Polyurethanes are classified into two types, depending on their curing mechanisms: moisture-cure urethanes and chemical-cure urethanes. Polyester and vinyl ester coatings are popular for lining applications, because polyesters can be formulated to tolerate very thick film builds. As thin coatings, they are commonly used for coil-coated products. Alkyds are relatively inexpensive and can be formulated into both solvent-borne and waterborne coatings. The other types of binders include epoxy esters and silicon-based inorganic zinc-rich coatings.
