Evaluation of Alkyd Primers

The objective of the research described in this report was to evaluate the performance and potential utility of commercially available alkyd primers in order to develop a Commercial Item Description CID for them. Alkyd paint systems include a wide range of natural and synthetic oil-based paint systems that have been used worldwide since ancient times to decorate and protect wood and metals. The U.S. Army Corps of Engineers and other Federal agencies use Steel Structures Painting Council SSPC Paint Specification No. 25, Red Iron Oxide, Zinc Oxide, Raw Linseed Oil and Alkyd Primer Without Lead and Chromate Pigments, when specifying a primer for alkyd topcoats. These coating systems are used for interior and exterior applications for steel where it is normally dry. SSPC-Paint 25 is a formulation-based product and is not readily available in the marketplace. In compliance with Federal policy to use commercial, off-the-shelf COTS items wherever possible, it is desirable to have performance-based specifications as opposed either to Federal or military specifications or to formulation-based industry specifications. One method to comply with the Federal policy and still have competitive procurement is to develop Commercial Item Descriptions, which are government specifications that describe COTS products with a specific level of quality. To develop a CID, commercial products must he evaluated to ensure that they are readily available in the open market and can provide a satisfactory level of performance. Eleven commercially available long oil alkyd primer coatings and an SSPC-Paint 25 control were applied to steel test plates and topcoated with a TT-E-489 gloss enamel topcoat. The test coatings were evaluated using laboratory tests designed to simulate exterior atmospheric weathering of poorly cleaned steel in a marine environment. Test panels were evaluated periodically for degree of rusting, blistering, and rust undercutting.