Advances in Waterborne Resins for Metal Coatings with Improved Corrosion Resistance

Abstract

Recent advances have shown that it is possible to provide outstanding corrosion resistance of metal with waterborne paint resins. Specifically, paints based on one-component waterborne polyurethanes (PUDs) can protect metal surfaces and keep them looking good for an extended period of time. In addition, paints based on two-component PUDs provide outstanding corrosion resistance along with excellent solvent and abrasion resistance. This paper will discuss the chemistry of PUDs and demonstrate the flexibility of this technology and the effect of polymer makeup on corrosion resistance. One-component waterborne polyurethane and waterborne polyacrylate resins were tested on metal after a variety of pre-treatments with and without a primer. The polyacrylates tested include a commercial formulation and Bayer’s in-house formulation to determine the effect of formulation variables. Two-component waterborne polyurethane systems were tested on metal to determine the corrosion resistance of paints that are known to have outstanding solvent and abrasion resistance. Typical properties of metal coatings were tested and will be discussed relative to chemical backbone of the resin.