A novel approach to thickening characterization of an acrylic latex thickener

Alkali-soluble latex thickeners are extensively used in activities such as coating manufacturing, cosmetics, and textile industry. They increase apparent viscosity as a result of neutralization of carboxyl groups present in latex particles. Rheometry is the main method used to monitor the rheological activity of these substances. In this manuscript, we propose the use of dynamic light scattering (DLS) to get quantitative parameters and correlate them to apparent viscosity increase, confirming the results using more traditional methods. More specifically, we monitored by DLS the characteristic and average relaxation rates, as well as the width of the relaxation rate distributions. Critical changes of these parameters were observed during thickening; drastic changes at the same point were confirmed by rheometry, conductometry, and turbidimetry.