Stoichiometry and structure of polyelectrolyte complex particles in diluted solutions

UV/VIS spectroscopy, potentiometry, viscometry, static and dynamic light scattering as well as electron microscopy were used to study the stoichiometry and structure of polyelectrolyte complexes between Na-poly(styrenesulfonate) and copolymers of diallyldimethylammonium chloride and acrylamide of various composition. In diluted, non-stoichiometric solutions polyelectrolyte complex formation leads to polydisperse systems of highly aggregated, nearly spherical particles, which are stabilized by a slight excess of the major component, At the 1:1 molar mixing ratio flocculation occurs. The structure density of the polyelectrolyte complexes depends strongly on the composition of the polycations.