Adsorption of Polyvinyl Alcohol on Al_2O_3, SiO_2 and Its Effect on the Zeta Potential of Particles

The adsorption isothermals of polyvinyl alcohol (PVA) on Al 2O 3 and SiO 2 particles have been measured. The effect of NaCl on the adsorption of PVA has been inspected. It is found that the adsorption amount increases rapidly with increase of PVA concentration when NaCl concentration is higher than 0.1mol/L. Zeta potentials of Al 2O 3 and SiO 2 particles with and without PVA adsorption have been obtained from the electrophoresis measurement. It is shown that the isoelectric point of SiO 2 is not affected by the adsorption of PVA, while the isoelectric point of Al 2O 3 decreases with the adsorption of PVA.