Abstract
In this paper, two phosphate functionalized acrylic binders are formulated to yield direct-to-metal paints without using corrosion inhibitors. The difference between both binders is the addition of polystearylacrylate crystalline nanodomains in one of them, and an amorphous methyl methacylate-co-butyl acrylate copolymer in the other. The water sensitivity, mechanical stability, adhesion, and the performance of the paints against corrosion (high humidity resistance, accelerated weathering, and salt-spray tests) are assessed and compared with a DTM paint formulated from a commercial binder. The performance of both phosphate functionalized paints formulated without corrosion inhibitors in high humidity and weathering tests is superior to the commercial DTM paint formulated without corrosion inhibitors and similar to the DTM paint formulated with them. Furthermore, the paint based on the amorphous copolymer binder provides significantly good performance in the salt spray test (even superior to that of the DTM paint formulated with corrosion inhibitors).
Highlights
Solventborne polymeric binders have been traditionally used in paint formulations for metal surfaces
The performance of both phosphate functionalized paints formulated without corrosion inhibitors in high humidity and weathering tests is superior to the commercial direct to metal coatings (DTM) paint formulated without corrosion inhibitors and similar to the DTM paint formulated with them
The paint based on the amorphous copolymer binder provides significantly good performance in the salt spray test
Summary
Solventborne polymeric binders have been traditionally used in paint formulations for metal surfaces. Barrier properties provided by a binder are not able to provide full corrosion protection to a coating, and the anticorrosion performance is markedly improved when anticorrosion pigments, inhibitors or additives are included in the paint formulation or in the binder itself. Afterwards, the anticorrosion performance of the phosphate containing latex binder was further enhanced by improving the barrier properties of the bare film through the introduction of crystalline nanodomains in the polymer particles (crystalline polystearyl acrylate (PSA) nanodomains) [13] All of these trials were made coating the metal substrates with the binder alone, before including it in a final paint formulation. High purity NaCl (Corrosalt, Ascott-Analytical, Tamworth, UK) was used for the preparation of a 5 wt% solutions during the corrosion tests
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
