Polymers grafted to a fluid and flexible membrane: Extreme sensitivity to the grafting densityA. Nicolas and B. Fourcade
UMR 5819, Groupe théorie, Département de Recherche Fondamentale sur la Matière Condensée, CEA-Grenoble, 38054 Grenoble cedex 9, France firstname.lastname@example.org
(Received 26 November 2002 and Received in final form 17 March 2003 / Published online: 12 May 2003)
Equilibrium phase coexistence between two chemical species implies the equality of the chemical potentials and of the osmotic pressures. We study this problem on a deformable membrane when one type of the molecules serves as anchor for polymeric chains immersed in the surrounding medium (considered as a good solvent). We derive the general conditions for phase coexistence when both the curvature of the membrane and the density field of the anchor molecule are free to adjust themselves. We show that curvature favors phase segregation. Our model predicts that membranes decorated with polymeric chains exhibit new shape bifurcations without equivalent in fixed density systems.
82.35.Gh - Polymers on surfaces; adhesion.
87.16.Dg - Membranes, bilayers and vesicles.
68.15.+e - Liquid thin films.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2003