粘度计法测定α-Al_2O_3水悬浮体系的最佳分散剂质量分数

Optimum Dispersant Mass Fraction of α-Al_2O_3 Aqueous Suspension Investigated by Viscometer

用Ubbelohde粘度计在pH=10时,测试了分散剂质量分数对α-Al2O3悬浮体系粘度的作用,并将此法与沉降法做了比较.结果表明,粘度法、沉降法所反映的悬浮体系稳定性随分散剂质量分数的变化规律基本是一致的.由粘度测试法得出,最佳分散剂的质量分数为0.04%,此条件下,α-Al2O3悬浮体系的粘度最低,且其最佳分散剂质量分数不随α-Al2O3悬浮体系的固相体积分数发生变化.在较宽的分散剂质量分数0.04%～0.24%内,均可得到粘度较低、悬浮稳定性较好的低固相体积分数的α-Al2O3悬浮体系.在最佳分散剂质量分数为0.04%、pH=10的条件下,制备了固相含量体积分数为62%的α-Al2O3浓悬浮体,并在剪切速率为49.81s-1时,测得其粘度为0.5Pa·s.

The effects of dispersant mass fraction on the suspension of particles in the α- Al2O3 suspension system and the viscosity of α- Al2O3 suspension system were investigated at pH = 10 using Ubbelohde viscometer. The measurment results show that the variation tendercy of stability with the change of dispersant mass fraction measured by viscosity is almost the same as that measured by suspersion. The viscosity experiment results show that the optimum dispersant mass fraction was 0.04% ,and under this condition, the lowest viscosity of α- Al2O3 suspension was obtained. The results further indicated the optimum dispersant mass fraction remained as a constant, which is independent of the solids loading. In low solids loading, the low viscosity and stable Al2O3 suspensions were obtained at 0. 04%-0. 24% dispersant mass fraction. 62% solids loading α- Al2O3 suspension is prepared at pH= 10, dispersant mass fraction of 0. 04%, and its viscosity measured by a rotary viscometer is 0.5 Pa·s at shear rate of 49.81s^-1.