Croatica Chemica Acta, Vol. 65 No. 2, 1992.
Original scientific paper
Conformational Transition of a Charged Polymer Chain Between Two Oppositely Charged Surfaces
Rudi Podgornik
; J. Stefan Institute, Theoretical Physics Department, 61111 Ljubljana, P.O.B. 100., Slovenia
Abstract
The paper deals with the intersurface forces in a system composed of two charged (membrane) surfaces immersed in a uni-uni valent electrolyte, effected by addition of an infinitely long, flexible polymeric chain carrying charges of the sign opposite to the one fixed on the surfaces. The conformation of the polymeric chain as a function of the intermembrane separation clearly displays the onset of an adsorption transition of the polymer characterized by a bimodal polymer segment distribution function. Polymer adsorption in a confined system leads to formation of bridges between the boundary surfaces that, in turn, contribute an attractive force component to the intersurface forces. This bridging attraction couples with the usual electrostatic double-layer forces in such a way that the total intermembrane force can become attractive or can even show two-phase equilibria.
Keywords
Hrčak ID:
137169
URI
Publication date:
15.8.1992.
Visits: 809 *