INFLUENCE OF THE SYNTHESIS CONDITIONS ON SOME PROPERTIES OF BOEHMITE HYDROSOLS

Boehmite hydrosols were synthesized by the hydrolysis of aluminum sec- butoxide followed by peptization with nitric acid at different acid/bo ehmite ratios (R). As R increases, the concentration of soluble forms of aluminum in the dispersion medium of the sol rises at virtually com plete interaction between the acid added and the boehmite particles. T he viscosity and density of the sols with different concentration of t he dispersed phase were measured. The sol particle density increases w ith R, and the dependence of the Huggins constant on R exhibits a mini mum, whose position corresponds to the conditions of the maximal aggre gation stability of the sol (R = 0.07-0.10). The rheological propertie s of the boehmite hydrosol are compared with the properties of the hyd rosols of silicon, titanium, and zirconium dioxides.