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Experimental Characterization of the Whipping Instability of Charged Microjets in Liquid Baths

Published online by Cambridge University Press:  01 February 2011

Guillaume Riboux
Affiliation:
griboux@us.es, Universidad de Sevilla, Ingeniería Aeroespacial, Seville, Spain
Álvaro Gómez-Marín
Affiliation:
a.g.marin@utwente.nl, Universidad de Sevilla, Ingeniería Aeroespacial, Seville, Spain
Antonio Barrero
Affiliation:
abarrero@us.es, Universidad de Sevilla, Ingeniería Aeroespacial, Seville, Spain
Alberto Fernández-Nieves
Affiliation:
alberto.fernandez@physics.gatech.edu, Georgia Institute of Technology, School of Physics, Atlanta, Georgia, United States
Ignacio G. Loscertales
Affiliation:
loscertales@uma.es, Universidad de Málaga, Mecánica de Fluidos, Málaga, Spain
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Abstract

Capillary liquid flows have shown their ability to generate micro and nano-structures which can be used to synthesize material in the micro or nanometric size range. For instance, electrified capillary liquid jets issued from a Taylor are broadly used to spin micro and nanofibers when the liquid consists of a polymer solution or melt, a process termed electrospinning. In this process, the electrified capillary jet may develop a nonaxisymmetric instability, usually referred to as whipping instability, which very efficiently transforms electric energy into stretching energy, thus leading to the formation of extremely thin polymer fibers. Even though non axysimmetric instabilities of electrified jets were first investigated some decades ago, the existing theoretical models provide a qualitative understanding of the phenomenon but none of them is accurate enough when compared with experimental results. This whipping instability usually manifests itself as fast and violent lateral motion of the charged jet, which makes it difficult its characterization in the laboratory. However, this instability also develops when electrospinning is performed within a liquid bath instead of air. Although it is essentially the same phenomenon, the frequency of the whipping oscillations is much slower in the former case than in the latter, thus allowing detailed experimental characterization of the whipping instability. Furthermore, since the outer fluid is a liquid, its density and viscosity may now be used to influence the dynamics of the electrified capillary jet. In this work we present and rationalize the experimental data collecting the influence of the main parameters on the whipping characteristics of the electrified jet (frequency, amplitude, etc.).

Type
Research Article
Copyright
Copyright © Materials Research Society 2010

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References

REFERENCES

1 Barrero, A. and Loscertales, I. G., Annu. Rev. Fluid Mech. 39, 89 (2007).Google Scholar
2 Hohman, M. M., Shin, M., Rutledge, G., and Brenner, M. P., Phys. Fluids, 13, 2201 (2001).Google Scholar
3 Reneker, D. H., Yarin, A. L., Fong, H., and Koombhongse, S., J. Appl. Phys. 87, 4531 (2000).Google Scholar
4 Yarin, A. L., Koombhongse, S., and Reneker, D. H., J. Appl. Phys. 89, 3018 (2001).Google Scholar
5 Barrero, A., Lpez-Herrera, J. M., Boucard, A., Loscertales, I. G., and Mrquez, M., J. Colloid Int. Sci. 272, 104 (2004).Google Scholar
6 Shin, Y. M., Hohman, M. M., Brenner, M. P., and Rutledge, G. C., Polymer, 42, 9955 (2001).Google Scholar
7 Hohman, M. M., Shin, M., Rutledge, G., and Brenner, M. P.. Phys. Fluids, 13, 2221 (2001).Google Scholar
8 Marn, A. G., Loscertales, I. G., Marquez, M., and Barrero, A., Phys. Rev. Lett. 98 (2007).Google Scholar
9 Higuera, F. J., J. Fluid Mech. 558, 143 (2006).Google Scholar
10 Taylor, G., Proc. R. Soc. A, 313, 453 (1969).Google Scholar