(797d) Understanding Fluctuation/Correlation Effects in Diblock Copolymer Melts With a Density-Functional Theory

With the polymer self-consistent field theory well developed and widely applied to many polymeric systems, it is both natural and timely to develop advanced theories that can quantitatively account for the fluctuations/correlations neglected by this mean-field theory. Here we formulate a density-functional theory for a model diblock copolymer system of discrete Gaussian chains interacting with soft, finite-range repulsions as commonly used in dissipative-particle dynamics simulations. Direct comparisons among the self-consistent field theory, the density-functional theory, and the fast off-lattice Monte Carlo simulations¹, all based on exactly the same model system and thus without any parameter-fitting, then unambiguously and quantitatively reveal the fluctuation/correlation effects on both the disordered and ordered phases, as well as the order-disorder transition, of diblock copolymer melts.

[1] Q. Wang and Y. Yin, J. Chem. Phys. 130, 104903 (2009).