The effect of poly(methacrylic acid) on electrosurface properties of titanium dioxide in aqueous suspensions

The electrosurface properties and aggregation stability of aqueous titanium-dioxide suspensions are studied in wide ranges of medium pH values and poly(methacrylic acid) concentrations. Using the 2pK model, the ionization constants of surface hydroxyl groups of titanium dioxide are found and it is established that the adsorption of poly(methacrylic acid) macromolecules substantially decreases the fraction of neutral (uncharged) hydroxyl groups and affects the ratio between the positively and negatively charged surface hydroxyl groups.