Modified sodium aluminium silicate — A highly dispersed polymer filler and a pigment

Abstract

Physicochemical properties of sodium aluminium silicates were characterized. The compounds were obtained by precipitation from sodium metasilicate solution using aluminium sulphate solution. Studies on the surface modification of a chosen sodium aluminium silicate using various types of proadhesive and hydrophobicity-inducing compounds are described. The best modifiers which induced a change of the silicate surface from hydrophilic to hydrophobic were selected. The extent of modification of the sodium aluminium silicate surface was estimated by measuring heats of immersion of its surface and by evaluation of the condensation of silicate silanol groups by a spectrophotometric method. Attempts were made to apply the modified sodium aluminium silicates in rubber mixtures (with natural rubber or butadiene-styrene rubber), in polyurethanes and in highly dispersed pigments.