Dispersion of glass powders in organic media

Adsorption and dispersion behaviors of glass powders in a binary solvent system of toluene and ethanol with poly(vinyl butyral) (PVB) and poly(methyl methacrylate) (PMMA) have been investigated. The composition of glass powder is varied from an optically basic calcium borosilicate glass to an acidic borosilicate glass. The adsorption of PVB is only observed on the basic calcium borosilicate glass while on the acidic borosilicate glass, PMMA is adsorbed. The adsorption characteristics are correlated with the state of particulate dispersion in suspensions using rheological measurements. A relatively poor solvent for polymers increases their adsorption on glass powders, thus improving the dispersion of glass powders in nonaqueous suspensions.