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Experimental studies of the deformation of a synthetic capsule in extensional flow

Published online by Cambridge University Press:  26 April 2006

K. S. Chang  and
W. L. Olbricht
K. S. Chang
Affiliation:
School of Chemical Engineering, Cornell University, Ithaca, NY 14853, USA Present address: Kimberly-Clark, 2100 Winchester Road, Neenah, WI 54957-0999, USA.
W. L. Olbricht
Affiliation:
School of Chemical Engineering, Cornell University, Ithaca, NY 14853, USA
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Abstract

Experiments are described to study the motion and deformation of a synthetic, liquid-filled capsule that is freely suspended in hyperbolic extensional flow. The capsule is a composite particle consisting of a viscous liquid drop surrounded by a thin polymeric membrane. The method used to fabricate capsules suitable for macroscopic flow experiments is described. The deformation of the capsule is measured as a function of strain rate for an extensional flow generated in a four-roll mill. The data agree well with results from small-deformation theory developed by Barthes-Biesel and co-workers, provided the deformation of the capsule is not too large. Using the theory to correlate the experimental data produces an estimate for the elastic modulus of the membrane that agrees reasonably well with the elastic modulus obtained by an independent technique. However, for sufficiently large strain rates, the membrane exhibits strain hardening and a permanent change in its structure, both of which are reflected in the shape of the capsule.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 250 , May 1993 , pp. 587 - 608
Copyright
© 1993 Cambridge University Press

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References

Acrivos, A. & Lo, T. S. 1978 Deformation and breakup of a single slender drop in an extensional flow. J. Fluid Mech. 86, 641–672.Google Scholar
Aklonis, J. J. & MacKnight, W. J. 1983 Introduction to Polymer Viscoelasticity. Wiley-Interscience.
Barthes-Biesel, D. 1980 Motion of a spherical microcapsule freely suspended in a linear shear flow. J. Fluid Mech. 100, 831–853.Google Scholar
Barthes-Biesel, D. 1991 Role of interfacial properties on the motion and deformation of capsules in shear flow. Physica A 172, 103–124.Google Scholar
Barthes-Biesel, D. & Acrivos, A. 1973a Deformation and burst of a liquid droplet freely suspended in a linear shear flow. J. Fluid Mech. 61, 1–21.Google Scholar
Barthes-Biesel, D. & Acrivos, A. 1973b The rheology of suspensions and its relation to phenomenological theories for non-Newtonian fluids. Intl J. Multiphase Flow 1, 1–24.Google Scholar
Barthes-Biesel, D. & Chhim, V. 1981 The constitutive equation of a dilute suspension of spherical microcapsules. Intl J. Multiphase Flow 7, 493–505.Google Scholar
Barthes-Biesel, D. & Rallison, J. M. 1981 The time-dependent deformation of a capsule freely suspended in a linear shear flow. J. Fluid Mech. 113, 251–267.Google Scholar
Barthes-Biesel, D. & Sgaier, H. 1985 Role of membrane viscosity in the orientation and deformation of a spherical capsule suspended in simple shear flow. J. Fluid Mech. 160, 119–135.Google Scholar
Bentley, B. J. 1985 Drop deformation and burst in two-dimensional flows. PhD thesis, California Institute of Technology.
Bentley, B. J. & Leal, L. G. 1986a A computer-controlled four-roll mill for investigations of particle and drop dynamics in two-dimensional linear shear flows. J. Fluid Mech. 167, 219–240.Google Scholar
Bentley, B. J. & Leal, L. G. 1986b An experimental investigation of drop deformation and breakup in steady, two-dimensional linear flows. J. Fluid Mech. 167, 241–283.Google Scholar
Brunn, P. O. 1983 The deformation of a viscous particle surrounded by an elastic shell in a general time-dependent linear flow field. J. Fluid Mech. 126, 533–544.Google Scholar
Chang, K. S. 1991 Experimental study of capsule motion and deformation in linear shear flows. PhD thesis, Cornell University.
Chang, K. S. & Olbricht, W. L. 1993, Experimental studies of the deformation and breakup of a synthetic capsule in steady and unsteady simple shear flow. J. Fluid Mech. 250, 609–633.Google Scholar
Chang, T. M. S., MacIntosh, R. C. & Mason, S. G. 1966 Semipermeable aqueous microcapsules. Can J. Physiol. Pharmacol. 44, 115–128.Google Scholar
Feng, W. W. & Yang, W. H. 1973 On the contact problem of an inflated spherical nonlinear membrane. Trans. ASME E: J. Appl. Mech. 40, 209–214.Google Scholar
Finch, C. A. 1985 Polymers for microcapsule walls. Chem. Ind. 22, 752–756.Google Scholar
Gutcho, M. H. 1976 Microcapsules and Microencapsulation Techniques. Noyes Data Corporation.
Hinch, E. J. & Acrivos, A. 1979 Steady long slender droplets in two-dimensional straining motion. J. Fluid Mech. 91, 401–414.Google Scholar
Hinch, E. J. & Acrivos, A. 1980 Long slender drops in a simple shear flow. J. Fluid Mech. 98, 305–328.Google Scholar
Lardner, T. J. & Pujara, P. 1977 Analysis of deformations of cell membranes. In Proc. Biomechanics Symp. Yale Univ., AMP 23 New Haven, Ct, pp. 65–67.
Lardner, T. J. & Pujara, P. 1978 On the contact problem of a highly inflated spherical nonlinear membrane. Trans. ASME E: J. Appl. Mech. 45, 202–203.Google Scholar
Lardner, T. J. & Pujara, P. 1980 Compression of spherical cells. Mech. Today 5, 161–176.Google Scholar
Li, X. Z., Barthes-Biesel, D. & Helmy, A. 1988 Large deformations and burst of a capsule freely suspended in an elongational flow. J. Fluid Mech. 187, 179–196.Google Scholar
MacRitchie, F. 1990 Chemistry at Interfaces. Academic.
Mathiowitz, E. & Cohen, M. D. 1989a Polyamide capsules for controlled release. I. Characterization of the membranes. J. Membrane Sci. 40, 1–26.Google Scholar
Mathiowitz, E. & Cohen, M. D. 1989b Polyamide capsules for controlled release. II. Release characteristics of the microcapsules. J. Membrane Sci. 40, 27–41.Google Scholar
Pozrikidis, C. 1990 The axisymmetric deformation of a red blood cell in uniaxial straining Stokes flow. J. Fluid Mech. 216, 231–254.Google Scholar
Rallison, J. M. 1980 Note on the time-dependent deformation of a viscous drop which is almost spherical. J. Fluid Mech. 98, 625–633.Google Scholar
Rallison, J. M. 1981 A numerical study of the deformation and burst of a viscous drop in general shear flows. J. Fluid Mech. 109, 465–482.Google Scholar
Rallison, J. M. & Acrivos, A. 1978 A numerical study of the deformation and burst of a viscous drop in an extensional flow. J. Fluid Mech. 89, 191–209.Google Scholar
Rodriguez, F. 1982 Principles of Polymer Systems. McGraw-Hill.
Taylor, G. I. 1934 The formation of emulsions in definable fields of flow. Proc. R. Soc. Lond. A 146, 501–523.Google Scholar
Thies, C. 1982 Microcapsules as drug delivery devices. In Critical Reviews in Biomedical Engineering. CRC Press.