SURFACE-PROPERTIES OF MICRON-SIZE POLYSTYRENE LATEX-PARTICLES PREPARED BY SEEDED POLYMERIZATION

It is well known that various monodisperse homo- and co- polymer latices in the submicrometer size range are prepared in the absence of emulsifier in a single stage process. The surface properties of these emulsifier-free polymer latices have been investigated by various methods, e.g. conductometric titration (1-7) and electrokinetic measurements (8). Monodisperse latex particles with a size greater than 1 μm are valuable for use in the biomedical field, e.g. as the carriers for medical diagnostic tests. Chung-li et al. (9) studied the preparation of monodisperse polystyrene latices with sizes in the range 1 to 4 μm by seeded polymerization in the absence of emulsifier, and they suggested that the particle growth is due to the heterocoagulation of the freshly formed particles onto the seed particles. In this work, monodisperse polystyrene latices with micrometer sizes were prepared by seeded polymerization in the absence of emulsifier. The ζ-potential and dispersion stability of the latex particles obtained were investigated. © 1991.