| Abstract: | The adsorption of an anionic-type polyelectrolyte (polyacrylamide) onto zirconium dioxide from aqueous dispersion has been studied as a function of pH. Polymer adsorption takes place in the acid region, obeying a Langmuir-type isotherm. Adsorption decreases with increasing pH. The zero-point of charge (zpc) at the ZrO2–H2O interface and the nature of the ionic charge on the polymer molecules were investigated. The behavior of polymer attachment is discussed on the grounds of a nonionic bonding mechanism including H bonding and of electrostatic interaction. It has been found that the zpc of ZrO2 is at pH ～3.5 and that the ionic properties of the polymer molecules depend, to a noticeable extent, upon the pH of the medium. |
