Eur. Phys. J. E 5, 41-49
Adsorption of a polyampholyte on a charged spherical particle
E. Zhulina, A.V. Dobrynin and M. RubinsteinDepartment of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290, USA avd@isis.unc.edu
(Received 3 March 2000 and Received in final form 5 July 2000 )
Abstract
We develop a scaling theory for a single polyampholyte chain adsorbed on a
charged spherical particle in a theta-solvent. Adsorption of a polyampholyte
molecule is due to its polarization in the electrostatic field of the
particle. For large particles with sizes exceeding the thickness of the
adsorbed layer, the conformations of the chain are similar to the one found
for polyampholyte adsorption on charged planar surface. However, an
adsorbed polyampholyte
chain forms a self-similar flower-like structure near the
particles with sizes smaller than its Gaussian size. These self-similar structures result from the balance of the
polarization energy of loops and the excluded volume interactions between
monomers. The structure of an adsorbed polyampholyte in the flower-like
conformation is similar to that of a neutral star polymer.
36.20.-r - Macromolecules and polymer molecules.
61.25.Hq - Macromolecular and polymer solutions; polymer melts; swelling.
68.45.-v - Solid-fluid interfaces.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2001