Adsorption of Poly(N-ethyl-4-vinyl pyridinium bromide) onto Langmuir-Blodgett Films Built up from Amphiphilic Polymers

摘要

The interaction of a strong cationic polyelectrolyte, poly(N-ethyl-4-vinyl pyridinium bromide), with Langmuir-Blodgett (LB) films built up from four monolayers of amphiphilic derivatives of the alternating copolymers of maleic acid and alkenes (one of the monolayers was formed by the amphiphilic copolymer containing pyrenyl groups as fluorescent labels) was examined. Transformations of absorbance spectra and quenching of fluorescence of the LB films were detected after their contact with aqueous solutions of the cationic polyelectrolyte. These changes were attributed to the adsorption of poly(N-ethyl-4-vinyl pyridinium bromide) onto such films. The efficiency of this process was found to be rather sensitive to the variations in pH of the surrounding medium: adsorption of the cationic polyelectrolyte onto the LB films was pronounced in basic media while it became rather weak in acidic media.