filament stretching extensional rheometer and capillary breakup extensional rheometer are used o measure the extensional rheology of a series of wormlike micelle solutions experiencing a niaxial elongational flow. The experiments are performed using a series of wormlike micelle olutions of both cetylpyridinium chloride and sodium salicylate NaSal in an aqueous sodium hloride solution and cetylt...

Various cellulose-ionic liquid solutions were measured with a rotational plate-andplate rheometer and a Capillary Break-up Extensional Rheometer (CaBER). Comparison of the shear and extensional rheological properties showed good agreement in some cases. The CaBER, however, seems to be more sensitive to small variations in solute composition. INTRODUCTION Since almost a decade now, nonderivatizi...

Film coating solutions containing different grades of HPMC (E5, E15 and E50) with and without polyethylene glycol (with various molecular weights) were examined by an oscillatory method, using Haake CV 100 rheometer. Fundamental rheological parameters (?, G? and G² ) were measured over the frequency range from 0.04 to 2 Hz. The variation with frequency of the loss tangent (a ratio of viscous to...

The rheological behaviour of ethylene glycol-based nanofluids containing hexagonal scalenohedral-shaped α-Fe2O3 (hematite) nanoparticles at 303.15 K and particle weight concentrations up to 25% has been carried out using a cone-plate Physica MCR rheometer. The tests performed show that the studied nanofluids present non-Newtonian shear-thinning behaviour. In addition, the viscosity at a given s...

The pharmaceutical industry requires the use of lubricants to prevent static electric buildup in the cohesive powders that are processed in manufacturing plants. In this report we examine the effects of common lubricant magnesium stearate on two flow properties, flow index and dynamic dilation, of lactose. We conducted two experiments using a gravitational displacement rheometer and a dynamic d...

We have studied the breaking of a two-dimensional alkane crystal above the disordered melt using an oscillating bubble rheometer. Surface tension changes abruptly during the expansion and contraction cycle. We postulate that this is due to rupture of the 2D crystal at grain boundaries. The magnitude of the abrupt change in surface tension decreases with a decrease in the rate of change of bubbl...

Homogeneous stable suspensions obtained by dispersing dry TiO2 nanoparticles in pure ethylene glycol were prepared and studied. Two types of nanocrystalline structure were analyzed, namely anatase and rutile phases, which have been characterized by scanning electron microscopy. The rheological behavior was determined for both nanofluids at nanoparticle mass concentrations up to 25%, including f...