Eur. Phys. J. B 5, 899-904 (1998)
https://doi.org/10.1007/s100510050515

Tension of polymers in a strip

¹ Instituto de Física, Universidade Federal Fluminense, A. Litorânea, s/n 24210-340, Niterói, RJ Brazil
² Departamento de Física Geral, Instituto de Física, Universidade de São Paulo, C.P. 66318 05315-970 São Paulo, SP Brazil

Corresponding author: ^a jstilck@if.uff.br

Received: 5 January 1998
Revised: 2 June 1998
Accepted: 4 June 1998
Published online: 15 October 1998

Abstract

We consider polymers, modelled as self-avoiding chains, confined on a strip defined on the square lattice with spacing a in the (x,y) plane, limited by two walls which are impenetrable to the chains and located at x=0 and x=am. The activity of a monomer incorporated into the chain is defined as and each monomer adsorbed on the wall, that is, located at sites with x=0 or x=m, contributes with a Boltzmann factor to the partition function. Therefore, corresponds to walls which are attractive to the monomers, while for the walls are repulsive. In particular, we calculate the tension between the walls, as a function of m and ω, for the critical activity z_c, at which the mean number of monomers diverges (the so called polymerization transition). For , the tension on the walls is repulsive for small values of m, becoming attractive as m is increased and finally becoming repulsive again. As ω is increased, the region of values of m for which the tension is attractive grows.