Fluctuating Field-Theoretic Polymer Simulations of Multispecies Melts and Composites

We discuss computational strategies for conducting efficient and stable beyond-mean-field simulations of complex multi-species block polymer melts and composites, with composition fluctuations included through complex Langevin sampling. Our framework is applicable to assemblies of polymer chains of a variety of architectures with interactions introduced through a matrix of Flory-Huggins parameters. We demonstrate the stability, efficiency, and accuracy of a multi-species exchange mapping, and apply the method to the study of fluctuation-induced microphase structures in blends and composites.