High performance water-borne paints with high volume solids based on bimodal latexes

The performance of water-borne paints formulated with five different high solids content acrylic (MMA/BA/MAA) latexes was investigated. These latexes had different particle size distributions (unimodal at 61 wt% and bimodal with the large mode below or above 350 nm at 65 wt% solids), different types of surfactant and in one case the carboxylic monomer was omitted.The results showed that both the particle size distribution of the latex and the paint thickening mechanism were found to be important contributors to wet paint viscosity and dry film properties. It was found that the water-borne paints formulated with the bimodal latex with particle sizes below 350 nm provided the best application properties in terms of drying time under ambient conditions, gloss (dependant on thickener type used), and mechanical properties of the paints.