Surface characterization of functionalized latexes with different surface functionalities using rheometry and dynamic light scattering.

Here we study the formation of sterically stabilizing "hairy" surface layers for a series of styrene-butylacrylate and styrene-butadiene latexes copolymerized either with acrylic acid (AA), methacrylic acid (MAA), itaconic acid (IA) or acrylamide (AM) using dynamic light scattering, steady shear and high frequency rheology. This phenomenon is investigated under different conditions of pH, ionic strength, and temperature. The AA copolymerized latex has the most extended hairy layer and is very sensitive to pH and ionic strength.

Sedimentation of concentrated monodisperse colloidal suspensions: role of collective particle interaction forces.

The sedimentation velocities and concentration profiles of low-charge, monodisperse hydroxylate latex particle suspensions were investigated experimentally as a function of the particle concentration to study the effects of the collective particle interactions on suspension stability. We used the Kossel diffraction technique to measure the particle concentration profile and sedimentation rate. We conducted the sedimentation experiments using three different particle sizes.