Viscoelasticity and shear flow of concentrated,noncrystallizing colloidal suspensions: Comparison with mode-coupling theory
Viscoelasticity and shear flow of concentrated,noncrystallizing colloidal suspensions: Comparison with mode-coupling theory
复制标题
浓非结晶胶体悬浮液的粘弹性和剪切流：与模式耦合理论的比较
DOI：
10.1122/1.3093088
复制
发表时间：
2008
影响因子：
3.3
通讯作者：
M. Ballauff
中科院分区：
文献类型：
--
作者：
M. Siebenbuerger;M. Fuchs;H. Winter;M. Ballauff
我们提出了一个全面的流变学研究的悬浮液的热敏颗粒分散在水中。这些颗粒的体积分数可以通过系统的温度以连续的方式调节。由于颗粒的有限多分散性（标准偏差：17%），结晶被抑制，没有液晶转变介入。因此，在线性粘弹性状态下的模量G '和G″以及流动曲线（剪切应力σ(γ)作为剪切速率γ的函数）可以在玻璃化转变附近的流体区域测量。在8个数量级的剪切速率范围内可以得到流动曲线，而在9个数量级以上的剪切速率范围内可以测量G '和G″。特别强调的是精确测量到最小的剪切速率/频率。结果表明，在瞬态积分框架中推广的模态耦合理论能够完整地描述流场曲线。
We present a comprehensive rheological study of a suspension of thermosensitive particles dispersed in water. The volume fraction of these particles can be adjusted by the temperature of the system in a continuous fashion. Due to the finite polydispersity of the particles (standard deviation: 17%), crystallization is suppressed and no fluid-crystal transition intervenes. Hence, the moduli G′ and G″ in the linear viscoelastic regime as well as the flow curves (shear stress σ(γ) as function of the shear rate γ) could be measured in the fluid region up to the vicinity of the glass transition. Moreover, flow curves could be obtained over a range of shear rates of 8 orders of magnitude, while G′ and G″ could be measured spanning over 9 orders of magnitude. Special emphasis has been laid on precise measurements down to the smallest shear rates/frequencies. It is demonstrated that mode-coupling theory generalized in the integration through transients framework provides a full description of the flow curves as ...