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The present study focuses on the adsorption of a polyelectrolyte, the component of which is a polymer of maleic anhydride sodium salt, on the surface of nanometric zinc oxide particles and the colloidal stability of aqueous dispersions. FTIR spectroscopic data provided evidence in support of hydrogen bonding and chemical interaction in the case of the polyelectrolyte-ZnO system. The adsorption iso-therms showed the influences of polyelectrolyte concentra-tion, pH and ionic strength on the adsorption. With the in-crease of pH the saturated adsorbed amount decreased, while the thickness of adsorption layer increased. The saturated adsorbed amount increased with increasing salt concentra-tion, and decreased with further increasing salt concentra-tion. It should be noted that in the presence of a CaCl2 solu-tion the adsorbed amount and the adsorption layer thickness were greater than those in the NaCl solution of the same concentration. The change of the absorbance of zinc oxide dispersions showed that the absorbance decreased slowly at high pH. There was a maximum point for the absorbance of the zinc oxide dispersions in the presence of various polye-lectrolyte concentrations. The change of dispersion stability resulted from the change of macromolecular chains confor-mation at the interface.
The present study focuses on the adsorption of a polyelectrolyte, the component of which is a polymer of maleic anhydride sodium salt, on the surface of nanometric zinc oxide particles and the colloidal stability of aqueous dispersions. FTIR spectroscopic data provided evidence in support of hydrogen bonding and chemical interaction in the case of the polyelectrolyte-ZnO system. The adsorption iso-therms showed the influences of polyelectrolyte concentra- tion, pH and ionic strength on the adsorption. With the in-crease of pH the saturated adsorbed amount decreased, while the thickness of adsorption layer increased. The saturated adsorbed amount increased with increasing salt concentra- tion, and decreased with further increasing salt concentra- tion. It should be noted that in the presence of a CaCl2 solu-tion the adsorbed amount and the adsorption layer thickness were greater than those in the NaCl solution of the same concentration. The change of the absorbance of zinc oxide dispersion s showed that the absorbance decreased slowly at high pH. There was a maximum point for the absorbance of the zinc oxide dispersions in the presence of various polye-lectrolyte concentrations. The change of dispersion stability resulted from the change of macromolecular chains confor-mation at the interface.