Preparation of concentrated aqueous suspensions from nanosized plasma-processed zirconia powder/ Korge kontsentratsiooniga happesuspensioonide valmistamine plasmatehnoloogiaga saadud nanosuurusega tsirkooniumpulbrist

Four commercially available dispersants have been compared for their ability to produce high-concentrated suspensions of the partially stabilized nanosized zirconia powder, processed by the plasma technique. Zeta potential measurements are used to study the influence of these dispersants on the electrokinetic properties of the powder surface. The highest solid loading (up to 70 wt%) is achieved using Atsurf 3222 and KD7 as dispersants. The optimal amounts of the dispersant (2-3 wt% of the dry mass of the solid) have been determined by adsorption and viscosity measurements. On the basis of obtained data, the correlation between the surface electrokinetic properties and maximal suspension concentration reached is discussed. Key words: zeta potential, adsorption, surfaces, surfactants, concentrated suspensions, nanosized zirconia. Plasmatehnoloogiaga saadud nanosuurusega osaliselt stabiliseeritud tsirkooniumpulbrist valmistatud korge kontsentratsiooniga suspensioone on vorreldud nelja dispergaatoriga. Zeta potentsiaali mootmise abil on uuritud nende dispergaatorite moju pulberpinna elektrokineetilistele omadustele. Korgeim kontsentratsioon (kuni 70 massiprotsenti) on saavutatud, kasutades dispergaatoreid Atsurf 3222 ja KD7. Optimaalne dispergaatori kogus (2-3 massiprotsenti) on maaratud absorptsiooni ja viskoossuse mootmisega. Nende andmete pohjal on analuusitud pinna elektrokineetiliste omaduste ja suspensiooni maksimaalse kontsentratsiooni korrelatsiooni.