Force-induced desorption of uniform block copolymers

Abstract

Abstract We investigate self-avoiding walk models of linear block copolymers adsorbed at a surface and desorbed by the action of a force. We rigorously establish the dependence of the free energy on the adsorption and force parameters, and the form of the phase diagram for several cases, including AB-diblock copolymers and ABA-triblock copolymers, pulled from an end vertex and from the central vertex. Our interest in block copolymers is partly motivated by the occurrence of a novel mixed phase in a directed walk model of diblock copolymers Iliev and Janse van Rensburg (2012 J. Stat. Mech. P01019) and we believe that this paper is the first rigorous treatment of a self-avoiding walk model of the situation.