盐离子对纳米氧化锆浆料流变性能的影响

Effect of Salt Ions on the Rheological Properties of Nano-sized Zirconia Slurry

通过测定浆料的Zeta电位和粘度曲线，研究了含高浓度盐溶液电解质（NaCl，NH4Cl，（NH4）2CO3）对纳米氧化锆浆料电动性能和流变性能的影响.研究结果表明，盐离子的加入可显著改变浆料的悬浮特性．增加盐离子的浓度，氧化锆浆料的Zeta电位降低，粘度增大．对同一种电解质而言，浆料的等电点并不随盐离子浓度的改变而改变，说明氧化锆浆料对这些盐离子无特性吸附．从浆料的粘度曲线可以看出，盐离子的加入均对浆料产生絮凝作用，使颗粒间产生一种互相吸引的架状结构，这种架状结构将导致浆料触变性的产生，并且高固相含量的ZrO2浆料对盐离子的加入反应更为敏感．

The electrophoretic and rheological properties of nano-zirconia slurries containing high concentrations of the electrolytes(NaCl, NH4Cl, (NH4)2CO3)were studied.It was indicated that zeta potential of zirconia slurries decreases when increasing the concentration of the electrolytes, but the isoelectric point(IEP) of the slurries is basically invariable.The IEP of zirconia slurries is different while in different species of electrolytes.An attractive,connective particle network is present with the addition of salt ions and induces to the thixotropy of the slurry. High solid content slurries are more sensitive to the salt ions expressed in the decreasing of critical coagulation concentration.Hence,the existence of electrolytes is disadvantageous to the preparation of high solid content slurries but can promote coagulation of the slurries.