KINETIC-THEORY AND THE FLORY-HUGGINS APPROXIMATION

A kinetic approach is used to examine the structure of the approximati ons that lead to the Flory-Huggins expression for the free energy of m ixing of a polymer solution. The kinetic model that we study can be so lved exactly in one dimension, and also on an infinite-dimensional lat tice, in which case it reduces to the Flory-Huggins formula. An approx imate solution that interpolates between these limits gives results fo r a three-dimensional lattice that differ rather little from those of the original Flory-Huggins theory. (C) 1996 American Institute of Phys ics.