摘要
The effect of surface hydroxyl groups (-OH) on the dispersity of ceramic powders was explored using the common ceramic powder barium titanate (BaTiO 3 ) as the study model. To simulate the presence of -OH on the powder, which is generally formed because of atmospheric storage, oxidative hydroxylation with hydrogen peroxide was used to produce and adjust the concentration of surface -OH. Owing to the presence of a lot of surface -OH, BaTiO 3 particles aggregated because of hydrogen bonding and required a large amount of dispersant such as the ammonium salt of poly(acrylic acid) (PAA-NH 4 ) for its dispersion stabilization. In addition, the commonly used binder poly(vinyl alcohol) (PVA) became more competitive with PAA-NH 4 for adsorption onto the hydroxylated BaTiO 3 , thereby reducing the efficiency of the dispersant and impeding the dispersion of the powder.