Non-equilibrium phase behavior of diblock copolymer melts and binary blends in the intermediate segregation regime

Renormalization of the one-loop theory of fluctuations in polymer blends and diblock copolymer melts.

Attempts to use coarse-grained molecular theories to calculate corrections to the random-phase approximation (RPA) for correlations in polymer mixtures have been plagued by an unwanted sensitivity to the value of an arbitrary cutoff length, i.e., by an ultraviolet (UV) divergence. We analyze the UV divergence of the inverse structure factor S(-1)(k) predicted by a "one-loop" approximation simil...

Monte Carlo phase diagram for diblock copolymer melts.

The phase diagram for diblock copolymer melts is evaluated from lattice-based Monte Carlo simulations using parallel tempering, improving upon earlier simulations that used sequential temperature scans. This new approach locates the order-disorder transition (ODT) far more accurately by the occurrence of a sharp spike in the heat capacity. The present study also performs a more thorough investi...

Evolution in off-critical diblock copolymer melts

We study the evolution of diblock copolymer melts in which one component has small volume fraction. In this case one observes phase morphologies which consist of small spheres of the minority component embedded in the other component. Based on the Ohta-Kawasaki free energy one can set up an evolution equation which has the interpretation of a gradient flow. We restrict this gradient flow to mor...

Equilibrium behavior of symmetric ABA triblock copolymer melts

Compositional and orientational ordering in rod - coil diblock copolymer melts

The phase behavior of a melt of monodisperse rod-coil diblocks is studied. We derive a Landau free energy functional for both a compositional and a nematic order parameter. The excluded volume interaction between the rod blocks is modeled by an attractive Maier-Saupe interaction. The incompatibility between rodand coil blocks is modeled by the usual Flory-Huggins interaction. For large volume f...