Surfactant-free latexes as binders in paint applications

[EN] The leakage of surfactant from waterborne coatings is a matter of concern. Therefore, there is a strong interest in developing surfactant-free polymer dispersion as binders for waterborne coatings. This will accelerate the sub-stitution of solventborne binders by the more environmentally friendly waterborne latexes. However, as the performance of the coating depends on the interaction of the latex with pigments and fillers and this interaction is controlled by the composition of the surface of the polymer particles, it is an open question if the surfactant-free latexes are adequate for coating applications. In this work, surfactant-free latexes synthesized under industrial-like conditions using sodium styrene sulfonate (NaSS) to provide stability to the latex were used to formulate exterior paints and their performance compared with that of a commercial latex binder. It was found that for most of the application properties, the paints based on the NaSS binders present improvements with respect to the surfactant stabilized commercial binder