NX-8501 Curing Agent Benefits and Applications
Our new NX-8501 is a waterborne curing agent for epoxy coatings and adhesives. This completely solvent free hardener enables zero and low VOC formulations without compromising performance. NX-8501 is a solution-type curing agent supplied at 80% solids in water. This material is easy to handle due to its low viscosity and ability to be further diluted by water or other co-solvents. NX-8501 is also compatible with various epoxy dispersion resins giving formulators latitude to work.
NX-8501 provides fast cure properties and hardness development regardless of the epoxy resin selected. Despite the fast dry speed, NX-8501 delivers long pot life with 3 to 4 hours working time achieved in our studies. Amongst all Cardolite’s waterborne epoxy curing agents, NX-8501 shows the best weatherability properties with low yellowing upon exposure to UV light.
Corrosion Protection to Various Substrates
Coatings based on NX-8501 demonstrated excellent adhesion and anticorrosion performance to a wide range of substrates. That included challenging non-blasted surfaces commonly used in automotive and agricultural and machinery equipment. More specifically, our evaluation looked at NX-8501 based primers on untreated cold rolled steel, aluminum alloy, galvanized steel, and stainless steel panels. All those systems successfully withstood long exposure of over 1500 hours in the salt spray cabinet. NX-8501 based primers also did very well on blasted steel surfaces as encountered in marine and protective coating applications. These coatings demonstrated good surface tolerance by providing excellent corrosion protection even over rusted panels. All systems were tested at low film thickness and were suitable options as primers, midcoats and direct-to-metal (DTM) coatings.
Moreover, NX-8501 based primers can be quickly recoated by top coats in wet-on-wet applications. Our evaluations show that epoxies based on this hardener can be recoated with polyurethanes in as fast as 15 minutes after application. Cure can take place at room temperature or in a 60°C oven. The final epoxy-polyurethane system provides excellent gloss (no die-back) and long lasting corrosion protection. This makes NX-8501 a great option for automotive refinish and other applications that require quick turnaround time.
NX-8501 technical data sheet and safety data sheets are available through our Waterborne Curing Agents page.