Heterogeneous polymer-containing films: a comparison of macroscopic properties with microscopic properties determined by atomic force microscopy

The aim of the study was to evaluate the extent to which a quantitative and automatic analysis of the surface properties of heterogeneous polymer-cont aining films such as paints is possible by atomic force microscopy. Therefo re, paints based on different dispersions were investigated. Force-distance curves were measured automatically at 64x64 points of the samples. From th e analysis of these force curves, a distribution of properties such as loca l elasticity, adhesion and penetration depth were obtained. Peaks in these distributions could be correlated with specific regions in the film such as binder or pigment. Peaks corresponding to the binder correlated with macro scopic properties such as glass transition temperature, tack and ball press ure hardness. In addition, from topographic images the roughness was calcul ated. As the roughness increases, the gloss decreases.