The Waterborne Symposium

Abstract
1K Polyurethane Dispersion with Comparable Performance to 2K Waterborne Coatings

Two component waterborne polyurethane (2KWB PU) coatings have been recognized as coatings with excellent performance properties and are used in a wide variety of applications.  However, they require the introduction of a curing agent as a second component to provide the crosslinking needed to enhance coating performance.  Several challenges for 2KWB PU coatings are well known, including limited pot life, increased waste, potential risk for mixing failure, and additional process steps before application.  Therefore, in certain markets, paint formulators continue to look for one component (1K) WB coatings that perform comparable to 2KWB coatings.  Furthermore, they also need to address increasingly stringent environmental regulations for low volatile organic compound (VOC) levels while still meeting technical requirements.  To meet these customer needs and more stringent regulations, an intensive polyurethane dispersion (PUD) development program was undertaken.  This paper discusses the performance properties of newly developed 1K PUD with both N-methyl pyrrolidone (NMP) containing and NMP-free PUDs that demonstrate comparable performance properties to 2KWB coatings.