分散剂用量对几种纳米氧化锆粉体尺寸表征的影响

Effect of Dispersant on the Measurement of Particle Size Distribution of Nano Size Y-TZP

本文研究了三种不同来源的纳米氧化锆粉体在尺寸表征中的影响因素．其中，加入的分散剂用量不同，测得的粉体颗粒尺寸有很大差别，不足或过量的分散剂影响粉体的颗粒尺寸分布．这种影响是通过改变粉体表面的电荷分布来实现的．超声时间长短是影响粉体尺寸表征的另一个重要因素．

Two factors which influence the measurement of particle size distribution were discussed. Selecting proper ultrasonic time can decrease the agglomeration of powders and lower the average particle size. Three kinds of nano-size Y-TZP powders require different amounts of dispersant to achieve lowest particle size. The optimum amount of dispersant for TZPI, TZP2 and TZP3 is 1.186%, 1.186% and 0.237% respectively. No significant improvement in the degree of dispersion was observed when the amount of dispersant exceeded the optimum value. The adsorbed polyelectrolyte results in a significant zeta potential on the particles and sterically prevents the particles from flocculating, leading to colloid stability increased. The PH of suspension is near to weaklybasic (pH=8.0) if NH4PAA is added even as little as 0.237%.