Lin Yuan, Phan-Thien Nhan, Lee Jason Boon Ping, Khoo Boo Cheong
†Department of Mechanical Engineering, National University of Singapore, Singapore 117576.
‡NUS-Keppel Corporate Laboratory, National University of Singapore, Singapore 117576.
Langmuir. 2015 Apr 28;31(16):4791-7. doi: 10.1021/acs.langmuir.5b00536. Epub 2015 Apr 16.
The concentration dependence of yield stress and dynamic moduli of kaolinite suspensions is studied. Complex electrostatic interactions between kaolinite platelets promote a more liquid-like behavior, with clay particles changing from attractive interactions to a face-face repulsive interaction as the mass fraction of clay particles increases. A yield stress model is developed based on the repulsive interaction between disk-shaped particles, which yields a good prediction of experimental observations when repulsive face-face interaction is dominant. The critical concentration when attractive interaction changes completely to face-face repulsive interaction is estimated from the theory. Four regions are identified in the variation of yield stress as a function of the concentration.
研究了高岭土悬浮液屈服应力和动态模量的浓度依赖性。高岭土薄片之间复杂的静电相互作用促进了更类似液体的行为，随着粘土颗粒质量分数的增加，粘土颗粒从吸引相互作用转变为面对面的排斥相互作用。基于盘状颗粒之间的排斥相互作用建立了屈服应力模型，当面对面的排斥相互作用占主导时，该模型能很好地预测实验观测结果。从理论上估计了吸引相互作用完全转变为面对面排斥相互作用时的临界浓度。在屈服应力随浓度变化的过程中确定了四个区域。
