科研之友
微信
新浪微博
Facebook
分享链接
摘要
Suspensions of cornstarch inwater exhibit strong dynamic shear thickening. We showthat partly replacingwater with ethanol strongly alters the suspension rheology. We perform steady and nonsteady rheology measurements combined with atomic force microscopy to investigate the role of fluid chemistry on the macroscopic rheology of the suspensions and its link with the interactions between cornstarch grains. Upon increasing the ethanol content, the suspension goes through a yield-stress fluid state and ultimately becomes a shear-thinning fluid. On the cornstarch grain scale, atomic force microscopy measurements reveal the presence of polymers on the cornstarch surface, which exhibit a cosolvency effect. At intermediate ethanol content, a maximum of polymer solubility induces high microscopic adhesion which we relate to the macroscopic yield stress.
- 出版日期2017-3-31
