| EP Primer 28 is a polyisocyanate prepolymer based on diphenylmethane diisocyanate (MDI). As corrosion-resistant primers, coatings based on EP Primer 28 polyisocyanate can be formulated to contain zinc as zinc-rich primers that give galvanic protection. To ensure satisfactory intercoat adhesion, recoating intervals must be determined. The high NCO content of EP Primer 28 also makes it an important curing agent for two-component systems. EP Primer 28 polyisocyanate is an outstanding material for moisture-curing one-component formulations and is highly recommended to prime and seal porous substrates. Clear formulations of this type are effective dust-binding impregnants as well as sealers for cement and other substrates because they can protect the substrate from chemicals, deicing salt, and mineral oils. Coatings based on EP Primer 28 polyisocyanate are also used for mold releasing in the building and construction industries. Because of their good resistance to alkalis, they are suitable adhesion primers for solvent-free coating compositions based on ReactAmine® polyisocyanates, ReactAmine® polyesters, and ReactAmine® polyethers. Appropriate catalysts may be added to coatings formulated with EP Primer 28 to influence the curing reaction rate. EP Primer 28 contains 15.5-17.5% NCO, and its equivalent weight is 255 (avg.). Part of the Amber Chemical Group. Data provided by manufacturer. Formerly Amber Chemical Co (ACC Silicones), aquired by CHT in 2017 |
