Eur. Phys. J. E 7, 241-250 (2002)
DOI: 10.1140/epje/i200101032
Hyperviscous diblock copolymer vesicles
R. Dimova1, 2, U. Seifert1, 3, B. Pouligny2, S. Förster4 and H.-G. Döbereiner11 Max-Planck-Institut für Kolloid- und Grenzflächenforschung, Am Mühlenberg 1, 14476 Golm, Germany
2 Centre de Recherche Paul Pascal, CNRS, Pessac 33600, France
3 Universität Stuttgart, Institut für Theoretische Physik II, Pfaffenwaldring 57, 70550 Stuttgart, Germany
4 Universität Hamburg, Institut für Physikalische Chemie, Bundesstraße 45, 20145 Hamburg, Germany
dimova@mpikg-golm.mpg.de
(Received 2 March 2001 and Received in final form 15 February 2002)
Abstract
Giant vesicles prepared from the diblock copolymer
polybutadien-b-polyethyleneoxide (PB-PEO) exhibit a shear surface viscosity,
which is about 500 times higher than those found in common phospholipid
bilayers. Our result constitutes the first direct measurement of the shear
surface viscosity of such polymersomes. At the same time, we measure bending
and stretching elastic constants, which fall in the range of values typical
for lipid membranes. Pulling out a tether from an immobilized polymersome
and following its relaxation back to the vesicle body provides an estimate
of the viscous coupling between the two monolayers composing the polymer
membrane. The detected intermonolayer friction is about an order of
magnitude higher than the characteristic one for phospholipid membranes.
Polymersomes are tough vesicles with a high lysis tension. This, together
with their robust rheological properties, makes them interesting candidates
for a number of technological applications.
83.50.Lh - Slip boundary effects (interfacial and free surface flows).
83.85.Jn - Viscosity measurements.
87.16.Dg - Membranes, bilayers, and vesicles.
87.80.Cc - Optical trapping.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2002
