Eur. Phys. J. E 9, 349-352 (2002)
DOI: 10.1140/epje/i2001-10113-8

Scale-dependent rigidity of polymer-ornamented membranes

T. Bickel and C.M. Marques

L.D.F.C. - UMR 7506, 3 rue de l'Université, 67084 Strasbourg Cedex, France

marques@LDFC.u-strasbg.fr

(Received 27 October 2001 and Received in final form 25 June 2002 / Published online: 7 January 2003)

Abstract
We study the fluctuation spectrum of fluid membranes carrying grafted polymers. Contrary to usual descriptions, we find that the modifications induced by the polymers cannot be reduced to the renormalization of the membrane bending rigidity. Instead we show that the ornamented membrane exhibits a scale-dependent elastic modulus that we evaluate. In ornamented lamellar stacks, we further compute the polymer contribution to the Caillé parameter characterizing the power law singularities of the Bragg peaks.

PACS
36.20.-r - Macromolecules and polymer molecules.
87.16.Dg - Membranes, bilayers, and vesicles.
82.35.Gh - Polymers on surfaces; adhesion.

© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2002