TY - JOUR
T1 - Charge screening effects on filament dynamics in xanthan gum solutions
AU - Smolka, Linda B.
AU - Belmonte, Andrew
N1 - Funding Information:
We would like to thank R.H. Colby, D.M. Henderson, A. Jayaraman, M.J. Shelley, P. Palffy-Muhoray, M. Rubinstein, and D. Bonn for discussions and suggestions, and R. Geist, A. Young and J. Marden for help with aspects of the experiments. AB acknowledges support from the A.P. Sloan Foundation and the National Science Foundation (CAREER Award DMR-0094167). LBS acknowledges partial support from the National Science Foundation (VIGRE grant DMS-9983320).
PY - 2006/8/30
Y1 - 2006/8/30
N2 - We experimentally investigate the filament dynamics of non-Newtonian drops falling under gravity through air, and report the effects of semi-dilute concentrations of the polyelectrolyte polymer xanthan gum mixed in 80:20 glycerol/water with varying concentrations of potassium chloride (KCl). We find that the addition of 780 ppm xanthan gum to the glycerol/water solvent dramatically increases the drop length just before pinch-off, by two orders of magnitude. This length is decreased by as much as an order of magnitude with the addition of KCl. The qualitative dynamics of bead formation on the filament is also very sensitive to added salt. These experimental observations are related to well-known changes in the molecular structure of xanthan gum due to charge screening effects.
AB - We experimentally investigate the filament dynamics of non-Newtonian drops falling under gravity through air, and report the effects of semi-dilute concentrations of the polyelectrolyte polymer xanthan gum mixed in 80:20 glycerol/water with varying concentrations of potassium chloride (KCl). We find that the addition of 780 ppm xanthan gum to the glycerol/water solvent dramatically increases the drop length just before pinch-off, by two orders of magnitude. This length is decreased by as much as an order of magnitude with the addition of KCl. The qualitative dynamics of bead formation on the filament is also very sensitive to added salt. These experimental observations are related to well-known changes in the molecular structure of xanthan gum due to charge screening effects.
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U2 - 10.1016/j.jnnfm.2006.01.012
DO - 10.1016/j.jnnfm.2006.01.012
M3 - Article
AN - SCOPUS:33748198191
SN - 0377-0257
VL - 137
SP - 103
EP - 109
JO - Journal of Non-Newtonian Fluid Mechanics
JF - Journal of Non-Newtonian Fluid Mechanics
IS - 1-3
ER -