ELECTROSTATIC ADSORPTION OF SURFACE CHARGED POLYSTYRENE NANOSPHERES ON CARBOXYMETHYLATED CHITOSAN SELF ASSEMBLED MONOLAYER

Atomic force microscopy (AFM) was chosen to investigate the electrostatic adsorption of PS nanospheres on carboxymethylated chitosan (CM-CHI ) self assembled monolayer,and the effect of the morphology of CM-CHI self assembled monolayer on the adsorption of PS nanospheres.The concentration of electrolyte,adsorption time and temperature of the process of PS adsorption were especially concerned in the adsorption kinetics study.For the CM-CMI self assembled monolayer prepared under the same condition,the respective electrolyte concentration for maximal coverage rate (Rc),48.0% at 20℃ is 0.5 mol/L,and the time for equilibrium adsorption is 20 min.The effect of the morphology of CM-CHI self assembled monolayers on the Rc was represented by the rapid increase of Rc with the rise of adsorption temperature.The reason of this phenomenon was discussed thoroughly in this paper.The drying process of carboxymethylated chitosan self assembled monolayer and the washing process of PS nanosphere adsorption were also discussed to investigate their contribution to the Rc.