Rheological behavior of fumed silica suspension in polyethylene glycol

来源期刊：中南大学学报(英文版)2006年第1期

论文作者：伍秋美 阮建明 黄伯云 周忠诚 邹俭鹏

文章页码：1 - 5

Key words：fumed silica suspension; polyethylene glycol; shear-thickening; storage modulus; loss modulus

Abstract: The rheological behavior of fumed silica suspensions in polyethylene glycol(PEG) was studied at steady and oscillatory shear stress using AR 2000 stress controlled rheometer. The systems show reversible shear thickening behavior and the shear-thickening behavior can be explained by the clustering mechanism. The viscosity and the degree of shear-thickening of the systems strongly depend on the mass fraction of the silica, the molecular weigh of PEG and the frequency used in the rheological measurement. The silica volume fraction of the systems is 1.16%-3.62%, corresponding to the mass fraction of 4% 9%. The shear-thickening taking place in the low volume fraction may contribute to the fractal nature of the silica. At oscillatory shear stress, when the shear stress is less than the critical stress, the storage modulus decreases significantly, meanwhile the loss modulus and the complex viscosity almost remain unchanged; when the shear stress is larger than the critical stress, the storage modulus, the loss modulus and the complex viscosity increase with the increase of shear stress. The loss modulus is larger than the storage modulus in the range of stress studied and both moduli depend on frequency.

基金信息：the National Natural Science Foundation of China