Shear-Thickening Behavior of Precipitated Calcium Carbonate Particles Suspensions in Glycerine

Applied Rheology

Xu Weijian¹  Zeng Guangsheng²  Liu Wenyong²  Chen Yi² 

[1] Institute of Polymer Research, College of Chemistry and Chemical Engineering, Hunan University,Changsha410082, P. R. China;Key Laboratory of Advanced Materials and Technology for Packaging of Hunan, Hunan University of Technology,Zhuzhou412008, P. R. China;

关键词: precipitated calcium carbonate;    glycerine;    shear-thickening;    rheological behavior;    steady shear;    dynamic oscillation;   

DOI  :  10.3933/applrheol-25-12466

来源: DOAJ

【 摘 要 】

For developing a new composite material owning shear-thickening characteristic, the rheological behaviors of nano-sized precipitated calcium carbonate (PCC) particles with irregular sharp in glycerine were investigated systematically by means of steady and dynamic rheometry. The results showed that the concentrated PCC suspensions exhibit a strong shear-thickening behavior under both steady and dynamic oscillatory shear when the volume fraction of PCC above the threshold (about 41%). In steady shear tests, the critical shear rate decreases and the maximum viscosity in shear thickening region increases dy namically with the increase of volume fraction. While, for suspensions with different volume fractions, the similar critical stress for the onset of shear thickening is found. In dynamic strain sweep at different fixed frequencies, with the increase of fixed frequency, the complex viscosity of suspensions decreases slightly, while the critical strain for shear-thickening shifts to lower value. The dynamic oscillatory rheological behavior of suspensions at low frequency (ω < 100 rad/s) could be reasonably interpreted in terms of the steady shear behavior. For the suspensions with same volume fraction, it was interestingly found that the critical dynamic shear rate equaled to the product of critical strain and frequency could agree well with the critical shear rate in steady shear. Moreover, the rheological behavior of PCC suspensions shows excellent reversibility and reproducibility.

【 授权许可】

Unknown