Thin multilayer films of weak polyelectrolytes on colloid particles

Abstract

We report the formation of poly(acrylic acid) (sodium salt) (PAA) and poly(allylamine hydrochloride) (PAH) multilayers on polystyrene (PS) and melamine formaldehyde (MF) colloid particles by the layer-by-layer (LbL) assembly technique. The use of different solution processing conditions (e.g., pH and ionic strength) was found to have a pronounced effect on film growth, with the degree of dissociation of both polyelectrolytes (PEs) playing an important role for regular PAA/PAH multilayer growth. To retain colloidal stability during the sequential adsorption of PEs, it was essential to deposit the PE layers from adsorption solutions where the PEs are in a highly charged state, the degree of wh..