Analysis of Polymer Latexes by Small-Angle X-Ray Scattering

This article reviews the structural analysis of polymeric latexes by small-angle X-ray scattering (SAXS). It is demonstrated that SAXS is a tool which allows us to study the internal structure as well as the interaction of latex particles with great accuracy. Since the SAXS-analysis of latexes requires highly accurate data down to smallest scattering angles, a detailed description of the experimental procedure and the subsequent data treatment will be given. In addition, a brief survey of instruments used up to now for SAXS-studies on latexes will be presented. Because of the low electron density of most of the polymers used in emulsion polymerization SAXS may be applied in conjunction with contrast variation. This method can be used for a precise analysis of the radial structure of the latex particles. Its application to the structural analysis of core-shell particles, to swollen latexes and to surfactants adsorbed on the particles surface will be discussed in detail.