WATERBORNE BINDER FOR PRIMER SYSTEMS: THE KEY TO VERSATILITY AND HIGH PERFORMANCE'

摘要

For decades the standard solvent-based 1-type solid epoxy resin/polyamidoamine system has dominated the field of corrosion protection for a variety of reasons including its excellent corrosion resistance and low cost. Unfortunately, the associated high VOC is gradually forcing coating manufacturers to formulate away from this aging technology. Reduction of the VOC level can acceptably be achieved by few methods. Waterborne technology offers the benefit of low VOC and can provide the high performance required today. A new waterborne epoxy binder system designed to meet the challenges facing the formulators of corrosion resistant primers has been presented in this paper. A starting point formulation that has outperformed a commercial solvent-based anti-corrosive primer has also been presented. Formulators using the waterborne amine curing agent CA-1 benefit from high quality corrosion resistant primers suited for a range of different and very specific applications. The main benefits of the CA-1 are its excellent adhesion to difficult substrates (i.e., poorly prepared or untreated steel, cold rolled steel, galvanized steel, aluminum etc.) and its outstanding compatibility with liquid epoxy resin and waterborne emulsions of both liquid and solid resins. Combination with the solid resin emulsion ER-1 helps achieve the best adhesion to the difficult substrates described above. Using CA-1, formulators can design primers with very low (even zero) VOC, low sensitization potential and good application properties. CA-1 may be used for industrial anti-corrosion primer applications, as well as heavy duty primers on blasted substrates - even when used at temperatures as low as 10 deg C with 80 percent relative humidity. Consequently, formulators can benefit from the versatility of CA-1 by using only one pigmented hardener base to cover many different primer applications. This versatility provides the tangible benefits of high performance, improved economics and logistics without the restrictions imposed by current VOC regulations.