Mixtures of cationic guar gum and anionic surfactants as stabilizers of zirconia suspensions

Mixtures of cationic guar gum (CGG) with some anionic surfactants from different chemical groups (hydrocarbon, fluorinated and silicone surfactants) were used as stabilizers of zirconia suspensions. Stabilization processes were analysed using spectrophotometric method, whereas the mechanism of stability was estimated using adsorption process (spectrophotometry, FTIR). The obtained results show that CGG is able to adsorb on the surface of zirconia and also can form complexes with each of the studied anionic surfactants. However, the affinity of these complexes towards the zirconia surface is different, what causes significant differences in stability of the zirconia/CGG/surfactant suspensions. In order to get some information of the structure and charge of the formed complexes the surface tension and the zeta potential measurements were used as supporting techniques. Among the studied polymer-surfactant systems, the complexes between CGG and sodium dodecyl sulphate (SDS) adsorbed on the zirconia surface the most effectively, and the consequence of this phenomenon was the increase of stability in this system.