COMPARISON OF A BORN-GREEN-YVON INTEGRAL-EQUATION TREATMENT OF A COMPRESSIBLE BINARY POLYMER BLEND ON A LATTICE WITH RECENT SIMULATIONS

Predictions of macroscopic and microscopic thermodynamic Properties of a polymer blend using the Born-Green-Yvon (BGY) integral equation tre atment of a compressible polymer mixture on a lattice are compared to recent simulations of compressible symmetric binary mixtures on a latt ice. The theory is consistent with recent simulation studies which ind icate that the critical temperature scales linearly with chain length. In addition, we show that the theory is effective in modeling the qua litative trends in the numbers of different types of pair contacts on the lattice, and also present comparisons of binodal and spinodal curv es. These comparisons indicate that quantitative differences between t he theory and simulation results are likely associated with the manner in which connectivity is treated in the lattice BGY description. We c onclude by discussing avenues whereby connectivity may be incorporated more consistently in the development of the theory.