Transient study on the shear thickening behaviour of surface modified fumed silica suspensions in polypropylene glycol

Abstract:

In this work, it is analysed the time dependent behaviour of Aerosil®R816 suspensions in polypropylene glycol with different molecular weights. On that purpose, hysteresis loops and stepwise experiments were carried out inside the reversible shear thickening region. On one hand, by means of the former, although the time dependence cannot be separated from shear rate, it can be observed rates of breakdown and rebuild of the "hydrodynamic clustering"; and, on the other hand, stepwise experiments let us analyse time response of these samples. It has been noticed that the lower the molecular weight of the polymer the quicker is the response of the sample, although it is weaker. The most relevant result is that these systems present the same "instantaneous" response when they are suddenly undergone to a certain value of shear rate, independently of the starting shear conditions. © 2008 American Institute of Physics.

Año de publicación:

2008

Keywords:

• suspension
• Shear thickening
• Fumed silica
• polypropylene glycol

Fuente:

scopus