Stimulation and binding properties of polyelectrolyte multilayers verifiedby ATR-FTIR spectroscopy

We report on the deposition and properties of multilayers composed of react ive polymers on planar surfaces. As reactive polymers the polycations poly( ethylene-imine), poly(l-lysine) (PLL), poly(allylamime) (PAA) and the polya nions poly(acrylate) (PAC), poly(vinylsulfate), poly(maleate-co-olefines) w ere used. ATR-FTIR spectroscopy was adopted to study deposition, binding an d stimulation properties of polymer multilayers. The binding of charged spe cies of different molecular size such as rhodanide anions and sodium oleate from solution was examined, whereby binding was found to be dependent on t he charge of the outermost layer. For these two analytes a selectivity para meter Q, defined as the ratio between the adsorbed amount obtained at the n egatively charged and that at the positively charged surface, respectively, was determined. Furthermore, swelling experiments on multilayer assemblies of PLL and PAC exposed to mixtures of ethanol/water (10 - 70% EtOH content ) were carried out. Our experiments gave evidence, that the PLL layers show ed a more significant increase in density than the PAC layers. The conforma tion of PLL incorporated into multilayers could be changed by pH variation.