ORDERING AND ADHESION OF LATEX-PARTICLES MODEL INORGANIC SURFACES

The ordering and adhesion of latex particles on model inorganic surface are. investigated through atomic force microscopy. The particles are made of a soft polymeric core protected by a hydrophilic membrane made of carboxylic acids, and they are dispersed in water. This dispersion is:spread on model inorganic surfaces. After water evaporation, there is a monolayer of rather well dispersed particles on the substrate. The measured particle heights are dependent on the scanning rate and on the force of the probe tip acting on the sample. Below the polymer glass temperature, the particles have weak adhesion to the surface and are moved easily by the probe tip. This results in tip-induced organization of the particles. The analysis of particle profiles shows that, above glass temperature, there is a sudden and partial spreading of the particles which Is governed by the polymeric chain mobility and not by capillary forces. The particle adhesion and spreading ratio are controlled by acid-base interactions between latex particles and the surface.