Measurements of polymer induced drag reduction and polymer scission in Taylor flow using standard double-gap sample holders with axial symmetry

The rheological properties of 1-50 ppm poly alpha -olefins in Varsol 80 wer e studied using laminar and Taylor flows. In Taylor how all the studied pol y ol-olefins displayed polymer induced drag reduction and polymer scission. The measurements were carried out using a commercial rheometer equipped wi th a standard double-gap sample holder with axial symmetry. We find that th is particular instrument even at the maximum obtainable geometrically avera ged shear rate of 15,000 s(-1) yields, an accuracy and a reproducibility be tter than +/-2.5%. This unique precision for measurements in the presence o f Taylor vortices, the small amounts of sample and time needed to carry out the measurements, and the general availability of the rheometer, suggests that these previously unexplored properties of this instrument will be of s ignificant Value for future investigations of polymer induced drag reductio n. (C) 2001 Elsevier Science B.V. All rights reserved.