EFFECT OF FUNCTIONAL-GROUPS OF POLYACRYLAMIDE AND POLYACRYLIC-ACID ON THEIR ADSORPTION ONTO TIO2 SURFACE

Fractions of polyacrylamide (PAM) and polyacrylic acid (PAA) of different molecular weights obtained by fractionation of polydisperse samples were investigated. The effect of molecular weight and functional groups of the polymers on their adsorption densities and the surface charge of TiO2 were studied using adsorption and potentiometric titration methods. On the basis of experimental data the probable mechanisms of adsorption of segments of PAM and PAA onto TiO2 surface were suggested. The biggest difference in the adsorption mechanisms for polyacrylamide and polyacrylic acid is observed for the acidic range of pH. Adsorption results of PAM in the plateau range were compared with the quantities calculated from Scheutjens-Fleer theory. © 1990.