Electrostatic self-assembled nano architectures between polycations of integral type and azo dyes

The electrostatic self-assembling was successfully used to build-up new pol ycation/azo dye multilayers starting from a polycation. of integral type co ntaining 95 mol.% of N,N-dimethyl-2-hydroxypropylencammonium chloride units in the main chain (PCA(5)) and two multicharged. azo dyes: Direct Blue 1 ( DB1) and Direct Red 80 (DR80). The build-up and the stability of the PCA(5) /azo dyes layered thin films, in dependence on the adsorption conditions an d the dye structure, were followed by UV-Vis spectroscopy, the variation of the zeta potential in dependence on pH and by spectroscopic ellipsometry. The multilayer build-up in the presence of the neutral salts was correlated with the counterion influence on the macroion conformation. The surface ch arge and the pH corresponding to the isoelectric point were depending on th e polycation adsorption conditions. (C) 2001 Elsevier Science B.V. All righ ts reserved.