Influence of short-range forces on wall-slip in microgel pastes
Influence of short-range forces on wall-slip in microgel pastes
复制标题
短程力对微凝胶糊壁滑移的影响
DOI：
10.1122/1.2963135
复制
发表时间：
2008
影响因子：
3.3
通讯作者：
R. Bonnecaze
中科院分区：
文献类型：
--
作者：
J. Seth;M. Cloître;R. Bonnecaze
软可变形颗粒的浓缩悬浮液，如聚合物微凝胶糊状物和压缩乳剂，显示出一般的滑移行为[Meeker et al.， J. Rheol. 92, 18302 (2004a)；李建军，刘建军，李建军，等。中国生物医学工程学报，2004,18(2):444 - 444。当与光滑的表面剪切时，由于在壁上滑动，它们表现出明显的运动。墙体滑移止于一个滑动屈服应力值，该值远低于体屈服应力。低应力下滑移的物理机制和滑移屈服应力的来源一直是尚未解决的问题。我们认为膏体与墙体的相互作用控制了墙体滑移行为，并决定了滑移屈服点的发生。我们提出了用不同的剪切面进行的实验。确定了两种不同的滑移行为：取决于微凝胶颗粒与壁面之间的相互作用是吸引还是排斥，壁面滑移可以被抑制或促进。本文给出了M…的弹性水动力滑移模型的扩展。
Concentrated suspensions of soft deformable particles, e.g., polymer microgel pastes and compressed emulsions, display a generic slip behavior [Meeker et al., J. Rheol. 92, 18302 (2004a); Meeker et al., J. Rheol. 48, 1295–1320 (2004b)]. When sheared with smooth surfaces, they exhibit apparent motion due to slip at the wall. Wall-slip stops at a sliding yield stress the value of which is much lower than the bulk yield stress. The physical mechanism of slip at low stresses and the origin of the sliding yield stress have so far been unresolved issues. We propose that the paste-wall interactions control the wall-slip behavior and determine the occurrence of the sliding yield point. We present experiments performed with different shearing surfaces. Two distinct slip behaviors are identified: depending on whether the interaction between the microgel particles and the wall is attractive or repulsive, wall-slip can be either suppressed or promoted. We provide an extension to the elastohydrodynamic slip model of M...